Commit Graph

4074 Commits

Author SHA1 Message Date
Alexandre Rames 700e63293e [Sema] Support Comma operator for fp16 vectors.
The current half vector was enforcing an assert expecting
 "(LHS is half vector) == (RHS is half vector)"
for comma.

Reviewed By: ahatanak, fhahn

Differential Revision: https://reviews.llvm.org/D88265
2020-09-30 18:23:09 +01:00
Richard Smith 1c604a9f5f Recognize setjmp and friends as builtins even if jmp_buf is not declared yet.
This happens in glibc's headers. It's important that we recognize these
functions so that we can mark them as returns_twice.

Differential Revision: https://reviews.llvm.org/D88518
2020-09-29 15:53:17 -07:00
Chris Hamilton 155d2d5300 Revert "[Sema] Address-space sensitive check for unbounded arrays (v2)"
This reverts commit d9ee935679.
2020-09-29 22:46:14 +02:00
Chris Hamilton d9ee935679 [Sema] Address-space sensitive check for unbounded arrays (v2)
Check applied to unbounded (incomplete) arrays and pointers to spot
cases where the computed address is beyond the largest possible
addressable extent of the array, based on the address space in which the
array is delcared, or which the pointer refers to.

Check helps to avoid cases of nonsense pointer math and array indexing
which could lead to linker failures or runtime exceptions.  Of
particular interest when building for embedded systems with small
address spaces.

This is version 2 of this patch -- version 1 had some testing issues
due to a sign error in existing code.  That error is corrected and
lit test for this chagne is extended to verify the fix.

Originally reviewed/accepted by: aaron.ballman
Original revision: https://reviews.llvm.org/D86796

Reviewed By: ebevhan

Differential Revision: https://reviews.llvm.org/D88174
2020-09-29 16:14:48 +02:00
Jan Korous 1e86d637eb [clang] Selectively ena/disa-ble format-insufficient-args warning
Differential Revision: https://reviews.llvm.org/D87176
2020-09-28 16:24:50 -07:00
Yuanfang Chen 10092291d7
[Clang] Fix a typo in implicit-int-float-conversion.c 2020-09-22 16:51:23 -07:00
Abhina Sreeskantharajan 0fb97fd6a4 [SystemZ][z/OS] Set default wchar_t type for zOS
Set the default wchar_t type on z/OS, and unsigned as the default.

Reviewed By: hubert.reinterpretcast, fanbo-meng

Differential Revision: https://reviews.llvm.org/D87624
2020-09-22 08:03:03 -04:00
David Spickett 349af80542 [clang][AArch64] Correct return type of Neon vqmovun intrinsics
Neon intrinsics vqmovunh_s16, vqmovuns_s32, vqmovund_s64
should have unsigned return types.

See https://developer.arm.com/architectures/instruction-sets/simd-isas/neon/intrinsics?search=vqmovun

Fixes https://bugs.llvm.org/show_bug.cgi?id=46840

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D85118
2020-09-21 09:21:51 +01:00
Dávid Bolvanský 2ae182258c [Diagnostics] Fixed -Wsizeof-array-div false positive when divisor is sizeof reference type (PR47495) 2020-09-20 17:43:06 +02:00
Raul Tambre e09107ab80 [Sema] Introduce BuiltinAttr, per-declaration builtin-ness
Instead of relying on whether a certain identifier is a builtin, introduce BuiltinAttr to specify a declaration as having builtin semantics.

This fixes incompatible redeclarations of builtins, as reverting the identifier as being builtin due to one incompatible redeclaration would have broken rest of the builtin calls.
Mostly-compatible redeclarations of builtins also no longer have builtin semantics. They don't call the builtin nor inherit their attributes.
A long-standing FIXME regarding builtins inside a namespace enclosed in extern "C" not being recognized is also addressed.

Due to the more correct handling attributes for builtin functions are added in more places, resulting in more useful warnings.
Tests are updated to reflect that.

Intrinsics without an inline definition in intrin.h had `inline` and `static` removed as they had no effect and caused them to no longer be recognized as builtins otherwise.

A pthread_create() related test is XFAIL-ed, as it relied on it being recognized as a builtin based on its name.
The builtin declaration syntax is too restrictive and doesn't allow custom structs, function pointers, etc.
It seems to be the only case and fixing this would require reworking the current builtin syntax, so this seems acceptable.

Fixes PR45410.

Reviewed By: rsmith, yutsumi

Differential Revision: https://reviews.llvm.org/D77491
2020-09-17 19:28:57 +03:00
Cullen Rhodes 9218f92838 [clang][aarch64] ACLE: Support implicit casts between GNU and SVE vectors
This patch adds support for implicit casting between GNU vectors and SVE
vectors when `__ARM_FEATURE_SVE_BITS==N`, as defined by the Arm C
Language Extensions (ACLE, version 00bet5, section 3.7.3.3) for SVE [1].

This behavior makes it possible to use GNU vectors with ACLE functions
that operate on VLAT. For example:

  typedef int8_t vec __attribute__((vector_size(32)));
  vec f(vec x) { return svasrd_x(svptrue_b8(), x, 1); }

Tests are also added for implicit casting between GNU and fixed-length
SVE vectors created by the 'arm_sve_vector_bits' attribute. This
behavior makes it possible to use VLST with existing interfaces that
operate on GNUT. For example:

  typedef int8_t vec1 __attribute__((vector_size(32)));
  void f(vec1);
  #if __ARM_FEATURE_SVE_BITS==256 && __ARM_FEATURE_SVE_VECTOR_OPERATORS
  typedef svint8_t vec2 __attribute__((arm_sve_vector_bits(256)));
  void g(vec2 x) { f(x); } // OK
  #endif

The `__ARM_FEATURE_SVE_VECTOR_OPERATORS` feature macro indicates
interoperability with the GNU vector extension. This is the first patch
providing support for this feature, which once complete will be enabled
by the `-msve-vector-bits` flag, as the `__ARM_FEATURE_SVE_BITS` feature
currently is.

[1] https://developer.arm.com/documentation/100987/latest

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D87607
2020-09-17 09:35:30 +00:00
Chris Hamilton c8ddf27ddb Revert "[Sema] Address-space sensitive index check for unbounded arrays"
This reverts commit da55e9ba12.

Build bots uncovered coverage gap in testing.  Change not ready.
2020-09-15 01:57:29 -05:00
Chris Hamilton da55e9ba12 [Sema] Address-space sensitive index check for unbounded arrays
Check applied to unbounded (incomplete) arrays and pointers
to spot cases where the computed address is beyond the
largest possible addressable extent of the array, based
on the address space in which the array is delcared, or
which the pointer refers to.

Check helps to avoid cases of nonsense pointer math and
array indexing which could lead to linker failures or
runtime exceptions.  Of particular interest when building
for embedded systems with small address spaces.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D86796
2020-09-14 18:13:19 -05:00
Mark de Wever 08196e0b2e Implements [[likely]] and [[unlikely]] in IfStmt.
This is the initial part of the implementation of the C++20 likelihood
attributes. It handles the attributes in an if statement.

Differential Revision: https://reviews.llvm.org/D85091
2020-09-09 20:48:37 +02:00
Cullen Rhodes f9091e56d3 [clang][aarch64] Drop experimental from __ARM_FEATURE_SVE_BITS macro
The __ARM_FEATURE_SVE_BITS feature macro is specified in the Arm C
Language Extensions (ACLE) for SVE [1] (version 00bet5). From the spec,
where __ARM_FEATURE_SVE_BITS==N:

    When N is nonzero, indicates that the implementation is generating
    code for an N-bit SVE target and that the arm_sve_vector_bits(N)
    attribute is available.

This was defined in D83550 as __ARM_FEATURE_SVE_BITS_EXPERIMENTAL and
enabled under the -msve-vector-bits flag to simplify initial tests.
This patch drops _EXPERIMENTAL now there is support for the feature.

[1] https://developer.arm.com/documentation/100987/latest

Reviewed By: david-arm

Differential Revision: https://reviews.llvm.org/D86720
2020-09-03 09:39:37 +00:00
Richard Smith 0ffbbce78d Don't take the expression range into account when looking for widening
of a unary - expression.

This fixes an issue where we'd produce bogus diagnostics, and also
should recover ~0.3% compile time.
2020-09-01 17:42:12 -07:00
Richard Smith f819dbf012 Classify (small unsigned bitfield) < 0 comparisons under
-Wtautological-unsigned-zero-compare not under
-Wtautological-value-range-compare.
2020-08-31 23:16:48 -07:00
Richard Smith cff6dda604 More accurately compute the ranges of possible values for +, -, *, &, %.
Continue to heuristically pick the wider of the two operands for
narrowing conversion warnings so that some_char + 1 isn't treated as
being wider than a char, but use the more accurate computation for
tautological comparison warnings.

Differential Revision: https://reviews.llvm.org/D85778
2020-08-31 23:16:48 -07:00
Cullen Rhodes feed5a7239 [Sema][AArch64] Support arm_sve_vector_bits attribute
This patch implements the semantics for the 'arm_sve_vector_bits' type
attribute, defined by the Arm C Language Extensions (ACLE) for SVE [1].
The purpose of this attribute is to define vector-length-specific (VLS)
versions of existing vector-length-agnostic (VLA) types.

The semantics were already implemented by D83551, although the
implementation approach has since changed to represent VLSTs as
VectorType in the AST and fixed-length vectors in the IR everywhere
except in function args/returns. This is described in the prototype
patch D85128 demonstrating the new approach.

The semantic changes added in D83551 are changed since the
AttributedType is replaced by VectorType in the AST. Minimal changes
were necessary in the previous patch as the canonical type for both VLA
and VLS was the same (i.e. sizeless), except in constructs such as
globals and structs where sizeless types are unsupported. This patch
reverts the changes that permitted VLS types that were represented as
sizeless types in such circumstances, and adds support for implicit
casting between VLA <-> VLS types as described in section 3.7.3.2 of the
ACLE.

Since the SVE builtin types for bool and uint8 are both represented as
BuiltinType::UChar in VLSTs, two new vector kinds are implemented to
distinguish predicate and data vectors.

[1] https://developer.arm.com/documentation/100987/latest

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D85736
2020-08-27 10:38:32 +00:00
Simon Pilgrim e7d9182a66 Enable constexpr on BITREVERSE builtin intrinsics (PR47249)
This enables us to use the __builtin_bitreverse 8/16/32/64 intrinsics inside constexpr code.

Differential Revision: https://reviews.llvm.org/D86339
2020-08-22 14:43:22 +01:00
Simon Pilgrim 2ceac91ec0 Enable constexpr on ROTATELEFT/ROTATERIGHT builtin intrinsics (PR47249)
This enables us to use the __builtin_rotateleft / __builtin_rotateright 8/16/32/64 intrinsics inside constexpr code.

Differential Revision: https://reviews.llvm.org/D86342
2020-08-22 14:43:21 +01:00
Craig Topper 724f570ad2 [X86] Add support 'tune' in target attribute
This adds parsing and codegen support for tune in target attribute.

I've implemented this so that arch in the target attribute implicitly disables tune from the command line. I'm not sure what gcc does here. But since -march implies -mtune. I assume 'arch' in the target attribute implies tune in the target attribute.

Differential Revision: https://reviews.llvm.org/D86187
2020-08-19 15:58:19 -07:00
Richard Smith 6f33936719 Explain why the array bound is non-constant in VLA diagnostics.
In passing, also use a more precise diagnostic to explain why an
expression is not an ICE if it's not of integral type.
2020-08-19 15:45:51 -07:00
Jon Chesterfield bcaa806a47 [Clang] Fix BZ47169, loader_uninitialized on incomplete types
[Clang] Fix BZ47169, loader_uninitialized on incomplete types

Reported by @erichkeane. Fix proposed by @erichkeane works, tests included.
Bug introduced in D74361. Crash was on querying a CXXRecordDecl for
hasTrivialDefaultConstructor on an incomplete type. Fixed by calling
RequireCompleteType in the right place.

Reviewed By: erichkeane

Differential Revision: https://reviews.llvm.org/D85990
2020-08-19 18:11:50 +01:00
Mott, Jeffrey T ca77ab494a Disable use of _ExtInt with '__atomic' builtins
We're (temporarily) disabling ExtInt for the '__atomic' builtins so we can better design their behavior later. The idea is until we do an audit/design for the way atomic builtins are supposed to work with _ExtInt, we should leave them restricted so they don't limit our future options, such as by binding us to a sub-optimal implementation via ABI.

Example after this change:

    $ cat test.c

        void f(_ExtInt(64) *ptr) {
          __atomic_fetch_add(ptr, 1, 0);
        }

    $ clang -c test.c

        test.c:2:22: error: argument to atomic builtin of type '_ExtInt' is not supported
          __atomic_fetch_add(ptr, 1, 0);
                             ^
        1 error generated.

Differential Revision: https://reviews.llvm.org/D84049
2020-08-18 09:17:26 -07:00
Dávid Bolvanský 2f7adf5ee3 [Diagnostics] Skip var decl of structs for -Wstring-concatenation 2020-08-13 20:20:26 +02:00
Michael Forster a5b8757506 Introduce ns_error_domain attribute.
ns_error_domain can be used by, e.g. NS_ERROR_ENUM, in order to
identify a global declaration representing the domain constant.

Introduces the attribute, Sema handling, diagnostics, and test case.

This is cherry-picked from a14779f504
and adapted to updated Clang APIs.

Reviewed By: gribozavr2, aaron.ballman

Differential Revision: https://reviews.llvm.org/D84005
2020-08-13 15:05:12 +02:00
Aleksandr Platonov 3fa0a039ab [clang] Check `expr` inside `InitListChecker::UpdateStructuredListElement()`
- Prevent nullptr-deference at try to emit warning for invalid `expr`
- Simplify `InitListChecker::UpdateStructuredListElement()` usages. We do not need to check `expr` and increment `StructuredIndex` (for invalid `expr`) before the call anymore.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D85193
2020-08-12 22:12:43 +03:00
Dávid Bolvanský b9af72bffe [Diagnostics] Reworked -Wstring-concatenation 2020-08-12 02:18:01 +02:00
Dávid Bolvanský 4b59dc77dc [Diagnostics] Ignore structs and long text for -Wstring-concatenation 2020-08-11 00:49:58 +02:00
Dávid Bolvanský b2c9b631bb [Diagnostics] Move -Wstring-concatenation to -Wextra 2020-08-10 23:36:33 +02:00
Dávid Bolvanský 62223ff137 [Diagnostics] Avoid false positives with -Wstring-concatenation 2020-08-10 23:05:01 +02:00
Dávid Bolvanský 975467e4aa [Diagnostics] Handle string concat pattern and avoid false positives 2020-08-09 16:02:41 +02:00
Dávid Bolvanský 04a23f1fe0 [Diagnostics] Turn string concat warning to avoid false positives 2020-08-09 12:22:29 +02:00
Dávid Bolvanský 6cd23558d3 [Clang] Fixed buildboit failure; bot defaults to older C++ standard 2020-08-08 19:37:50 +02:00
Dávid Bolvanský dc096a66cb [Diagnostics] Diagnose missing comma in string array initialization
Motivation (from PR37674):

const char *ss[] = {
  "foo", "bar",
  "baz", "qux"  // <-- Missing comma!
  "abc", "xyz"
  };

This kind of bug was recently also found in LLVM codebase (see PR47030).

Solves PR47038, PR37674

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D85545
2020-08-08 19:24:30 +02:00
Vince Bridgers 351aac0985 [Sema] Add casting check for fixed to fixed point conversions
This change squelches the warning for a cast from fixed to fixed point
conversions when -Wbad-function-cast is enabled.

Fixes:

cast from function call of type '_Fract' to non-matching type '_Fract'
[-Wbad-function-cast]

Reviewed By: bjope

Differential Revision: https://reviews.llvm.org/D85157
2020-08-07 07:58:53 -05:00
Simon Tatham 1d78294250 [Sema][BFloat] Forbid arithmetic on vectors of bfloat.
Vectors of bfloat are a storage format only; you're supposed to
explicitly convert them to a wider type to do arithmetic on them.
But currently, if you write something like

  bfloat16x4_t test(bfloat16x4_t a, bfloat16x4_t b) { return a + b; }

then the clang frontend accepts it without error, and (ARM or AArch64)
isel fails to generate code for it.

Added a rule in Sema that forbids the attempt from even being made,
and tests that check it. In particular, we also outlaw arithmetic
between vectors of bfloat and any other vector type.

Patch by Luke Cheeseman.

Reviewed By: LukeGeeson

Differential Revision: https://reviews.llvm.org/D85009
2020-08-07 11:25:19 +01:00
Richard Smith d6492d8744 Add -Wtautological-value-range-compare warning.
This warning diagnoses cases where an expression is compared to a
constant, and the comparison is tautological due to the form of the
expression (but not merely due to its type). This applies in cases such
as comparisons of bit-fields and the result of bit-masks.

The new warning is added to the Clang diagnostic group
-Wtautological-constant-in-range-compare but not to the
formerly-equivalent GCC-compatibility diagnostic group -Wtype-limits,
which retains its old meaning of diagnosing only tautological
comparisons to extremal values of a type (eg, int > INT_MAX).

Reviewed By: rtrieu

Differential Revision: https://reviews.llvm.org/D85256
2020-08-06 13:28:50 -07:00
Yonghong Song 6d67506964 [clang][BPF] support type exist/size and enum exist/value relocations
This patch added the following additional compile-once
run-everywhere (CO-RE) relocations:
  - existence/size of typedef, struct/union or enum type
  - enum value and enum value existence

These additional relocations will make CO-RE bpf programs more
adaptive for potential kernel internal data structure changes.

For existence/size relocations, the following two code patterns
are supported:
  1. uint32_t __builtin_preserve_type_info(*(<type> *)0, flag);
  2. <type> var;
     uint32_t __builtin_preserve_field_info(var, flag);
flag = 0 for existence relocation and flag = 1 for size relocation.

For enum value existence and enum value relocations, the following code
pattern is supported:
  uint64_t __builtin_preserve_enum_value(*(<enum_type> *)<enum_value>,
                                         flag);
flag = 0 means existence relocation and flag = 1 for enum value.
relocation. In the above <enum_type> can be an enum type or
a typedef to enum type. The <enum_value> needs to be an enumerator
value from the same enum type. The return type is uint64_t to
permit potential 64bit enumerator values.

Differential Revision: https://reviews.llvm.org/D83242
2020-08-04 08:39:53 -07:00
Erich Keane 0a8ac91a08 Permit nowthrow and nonnull with multiversioning.
Some shipped versions of stdlib.h use nonnull and nothrow with function
multiversioning.  Support these, as they are generally harmless.
2020-08-04 07:40:27 -07:00
Erich Keane 961da69d7e Improve diagnostics for disallowed attributes used with multiversioning
Since we permit using SOME attributes (at the moment, just 1) with
multiversioning, we should improve the message as it still implies that
no attributes should be combined with multiversioning.
2020-08-04 07:40:27 -07:00
Bruno Ricci b0512eed1e
[clang][NFC] Add a test for __attribute__((flag_enum)) with an unnamed enumeration. 2020-07-26 17:24:43 +01:00
Richard Smith 6c18f7db73 For PR46800, implement the GCC __builtin_complex builtin.
glibc's implementation of the CMPLX macro uses it (with -fgnuc-version
set to 4.7 or later).
2020-07-22 13:43:10 -07:00
Cullen Rhodes 89e61e782b [Sema][AArch64] Add semantics for arm_sve_vector_bits attribute
Summary:
This patch implements semantics for the 'arm_sve_vector_bits' type
attribute, defined by the Arm C Language Extensions (ACLE) for SVE [1].
The purpose of this attribute is to define fixed-length (VLST) versions
of existing sizeless types (VLAT).

Implemented in this patch is the the behaviour described in section 3.7.3.2
and minimal parts of sections 3.7.3.3 and 3.7.3.4, this includes:

    * Defining VLST globals, structs, unions, and local variables
    * Implicit casting between VLAT <=> VLST.
    * Diagnosis of ill-formed conditional expressions of the form:

        C ?  E1 : E2

      where E1 is a VLAT type and E2 is a VLST, or vice-versa. This
      avoids any ambiguity about the nature of the result type (i.e is
      it sized or sizeless).
    * For vectors:
        * sizeof(VLST) == N/8
        * alignof(VLST) == 16
    * For predicates:
        * sizeof(VLST) == N/64
        * alignof(VLST) == 2

VLSTs have the same representation as VLATs in the AST but are wrapped
with a TypeAttribute. Scalable types are currently emitted in the IR for
uses such as globals and structs which don't support these types, this
is addressed in the next patch with codegen, where VLSTs are lowered to
sized arrays for globals, structs / unions and arrays.

Not implemented in this patch is the behaviour guarded by the feature
macros:

    * __ARM_FEATURE_SVE_VECTOR_OPERATORS
    * __ARM_FEATURE_SVE_PREDICATE_OPERATORS

As such, the GNU __attribute__((vector_size)) extension is not available
and operators such as binary '+' are not supported for VLSTs. Support
for this is intended to be addressed by later patches.

[1] https://developer.arm.com/documentation/100987/latest

This is patch 2/4 of a patch series.

Reviewers: sdesmalen, rsandifo-arm, efriedma, cameron.mcinally, ctetreau, rengolin, aaron.ballman

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D83551
2020-07-22 16:26:23 +00:00
David Goldman dde98c82c0 Fix issue in typo handling which could lead clang to hang
Summary:
We need to detect when certain TypoExprs are not being transformed
due to invalid trees, otherwise we risk endlessly trying to fix it.

Reviewers: rsmith

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D84067
2020-07-20 11:42:11 -04:00
Erich Keane 66aff32398 Issue error on invalid arithemtic conversions in C ternary
As reported in PR46774, an invalid arithemetic conversion used in a C
ternary operator resulted in an assertion. This patch replaces that
assertion with a diagnostic stating that the conversion failed.

At the moment, I believe the only case of this happening is _ExtInt
types.
2020-07-20 08:02:37 -07:00
Bruno Ricci acf3bdc283
[clang][NFC] Tests showing the problems with some uses of NamedDecl::getDeclName in diagnostics, SemaOverload.cpp+SemaStmt.cpp part 2020-07-18 20:44:06 +01:00
Yaxun (Sam) Liu 9275e14379 recommit 4fc752b30b [CUDA][HIP] Always defer diagnostics for wrong-sided reference
Fixed regression in test builtin-amdgcn-atomic-inc-dec-failure.cpp.
2020-07-17 09:14:39 -04:00
Cullen Rhodes bb160e769d [Sema][AArch64] Add parsing support for arm_sve_vector_bits attribute
Summary:

This patch implements parsing support for the 'arm_sve_vector_bits' type
attribute, defined by the Arm C Language Extensions (ACLE, version 00bet5,
section 3.7.3) for SVE [1].

The purpose of this attribute is to define fixed-length (VLST) versions
of existing sizeless types (VLAT). For example:

    #if __ARM_FEATURE_SVE_BITS==512
    typedef svint32_t fixed_svint32_t __attribute__((arm_sve_vector_bits(512)));
    #endif

Creates a type 'fixed_svint32_t' that is a fixed-length version of
'svint32_t' that is normal-sized (rather than sizeless) and contains
exactly 512 bits. Unlike 'svint32_t', this type can be used in places
such as structs and arrays where sizeless types can't.

Implemented in this patch is the following:

  * Defined and tested attribute taking single argument.
  * Checks the argument is an integer constant expression.
  * Attribute can only be attached to a single SVE vector or predicate
    type, excluding tuple types such as svint32x4_t.
  * Added the `-msve-vector-bits=<bits>` flag. When specified the
    `__ARM_FEATURE_SVE_BITS__EXPERIMENTAL` macro is defined.
  * Added a language option to store the vector size specified by the
    `-msve-vector-bits=<bits>` flag. This is used to validate `N ==
    __ARM_FEATURE_SVE_BITS`, where N is the number of bits passed to the
    attribute and `__ARM_FEATURE_SVE_BITS` is the feature macro defined under
    the same flag.

The `__ARM_FEATURE_SVE_BITS` macro will be made non-experimental in the final
patch of the series.

[1] https://developer.arm.com/documentation/100987/latest

This is patch 1/4 of a patch series.

Reviewers: sdesmalen, rsandifo-arm, efriedma, ctetreau, cameron.mcinally, rengolin, aaron.ballman

Reviewed By: sdesmalen, aaron.ballman

Differential Revision: https://reviews.llvm.org/D83550
2020-07-17 10:06:54 +00:00
Mott, Jeffrey T d083adb068 Prohibit use of _ExtInt in atomic intrinsic
The _ExtInt type allows custom width integers, but the atomic memory
access's operand must have a power-of-two size. _ExtInts with
non-power-of-two size should not be allowed for atomic intrinsic.

Before this change:

$ cat test.c

typedef unsigned _ExtInt(42) dtype;
void verify_binary_op_nand(dtype* pval1, dtype val2)
{    __sync_nand_and_fetch(pval1, val2); }

$ clang test.c

clang-11:
/home/ubuntu/llvm_workspace/llvm/clang/lib/CodeGen/CGBuiltin.cpp:117:
llvm::Value*
EmitToInt(clang::CodeGen::CodeGenFunction&, llvm::Value*,
clang::QualType, llvm::IntegerType*): Assertion `V->getType() ==
IntType' failed.
PLEASE submit a bug report to https://bugs.llvm.org/ and include the
crash backtrace, preprocessed source, and associated run script.

After this change:

$ clang test.c

test.c:3:30: error: Atomic memory operand must have a power-of-two size
{    __sync_nand_and_fetch(pval1, val2); }
^

List of the atomic intrinsics that have this
problem:

__sync_fetch_and_add
__sync_fetch_and_sub
__sync_fetch_and_or
__sync_fetch_and_and
__sync_fetch_and_xor
__sync_fetch_and_nand
__sync_nand_and_fetch
__sync_and_and_fetch
__sync_add_and_fetch
__sync_sub_and_fetch
__sync_or_and_fetch
__sync_xor_and_fetch
__sync_fetch_and_min
__sync_fetch_and_max
__sync_fetch_and_umin
__sync_fetch_and_umax
__sync_val_compare_and_swap
__sync_bool_compare_and_swap

Differential Revision: https://reviews.llvm.org/D83340
2020-07-14 06:11:04 -07:00
Aaron Ballman 006c49d890 Change behavior with zero-sized static array extents
Currently, Clang previously diagnosed this code by default:
  void f(int a[static 0]);
saying that "static has no effect on zero-length arrays", which was
accurate.

However, static array extents require that the caller of the function
pass a nonnull pointer to an array of *at least* that number of
elements, but it can pass more (see C17 6.7.6.3p6). Given that we allow
zero-sized arrays as a GNU extension and that it's valid to pass more
elements than specified by the static array extent, we now support
zero-sized static array extents with the usual semantics because it can
be useful in cases like:

  void my_bzero(char p[static 0], int n);
  my_bzero(&c+1, 0); //ok
  my_bzero(t+k,n-k); //ok, pattern from actual code
2020-07-10 15:58:11 -04:00
Erik Pilkington dafc3106d2 [Sema] Emit a -Wformat warning for printf("%s", (void*)p)
Its dangerous to assume that the opaque pointer points to a null-terminated
string, and this has an easy fix (casting to char*).

rdar://62432331
2020-07-10 15:10:24 -04:00
Zhi Zhuang 4d4d903767 Fix warning caused by __builtin_expect_with_probability was not handled
in places such as constant folding

Previously some places that should have handled
__builtin_expect_with_probability is missing, so in some case it acts
differently than __builtin_expect.
For example it was not handled in constant folding, thus in the
following program, the "if" condition should be constantly true and
folded, but previously it was not handled and cause warning "control may
reach end of non-void function" (while __builtin_expect does not):

__attribute__((noreturn)) extern void bar();
int foo(int x, int y) {
  if (y) {
    if (__builtin_expect_with_probability(1, 1, 1))
      bar();
  }
  else
    return 0;
}

Now it's fixed.

Differential Revisions: https://reviews.llvm.org/D83362
2020-07-09 08:01:33 -07:00
Aleksandr Platonov 1ba6fb9293
[clang] Fix a crash when passing a C structure of incompatible type to a function with a reference parameter.
__builtin_va_*() and __builtin_ms_va_*() are declared as functions with a
parameter of reference type.

This patch fixes a crash when using these functions in C where an argument
of structure type is incompatible with the parameter type.

Differential Revision: https://reviews.llvm.org/D82805

Reviewed By: riccibruno

Patch by: Aleksandr Platonov <platonov.aleksandr@huawei.com>
2020-07-08 16:57:54 +01:00
Saiyedul Islam 0882c9d4fc [AMDGPU] Change Clang AMDGCN atomic inc/dec builtins to take unsigned values
builtin_amdgcn_atomic_inc32(uint *Ptr, uint Val, unsigned MemoryOrdering, const char *SyncScope)
builtin_amdgcn_atomic_inc64(uint64_t *Ptr, uint64_t Val, unsigned MemoryOrdering, const char *SyncScope)
builtin_amdgcn_atomic_dec32(uint *Ptr, uint Val, unsigned MemoryOrdering, const char *SyncScope)
builtin_amdgcn_atomic_dec64(uint64_t *Ptr, uint64_t Val, unsigned MemoryOrdering, const char *SyncScope)

As AMDGCN IR instrinsic for atomic inc/dec does unsigned comparison,
these clang builtins should also take unsigned types instead of signed
int types.

Reviewed By: JonChesterfield

Differential Revision: https://reviews.llvm.org/D83121
2020-07-07 06:36:25 +00:00
Haojian Wu cd9a241f16 [clang] Fix the incorrect dependence bits for DependentExtIntType.
The error-bit was missing, and the unexpandedpack bit seemed to be
set incorrectly.

Reviewed By: sammccall, erichkeane

Differential Revision: https://reviews.llvm.org/D83114
2020-07-06 16:42:56 +02:00
Dmitry Preobrazhensky 53422e8b4f [AMDGPU] Added support of new inline assembler constraints
Added support for constraints 'I', 'J', 'L', 'B', 'C', 'Kf', 'DA', 'DB'.

See https://gcc.gnu.org/onlinedocs/gcc/Machine-Constraints.html#Machine-Constraints.

Reviewers: arsenm, rampitec

Differential Revision: https://reviews.llvm.org/D81657
2020-07-03 18:01:12 +03:00
Haojian Wu d28267f981 [AST][RecoveryExpr] Add error-bit to NestNameSpecifierDependence and TemplateNameDependence.
Summary:
We might lose the error-bit if the error-bit goes through the code path
"error type/expr" -> "error template argument" -> "nested name specifier" ->
... -> "template Specialization type"

Template name also needs this, as a template can be nested into
an error specifier, e.g. templateName apply in
`TC<decltype(<recovery-expr>(Foo, int()))>::template apply`

Reviewers: sammccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D82526
2020-06-30 11:56:24 +02:00
Cullen Rhodes 1ef75f53e9 [AArch64][SVE] clang: Add missing svbfloat16_t tests
Summary:
Patch adds tests for mangling of svbfloat16_t and several other type
related tests.

Reviewers: sdesmalen, kmclaughlin, fpetrogalli, efriedma

Reviewed By: sdesmalen, fpetrogalli

Differential Revision: https://reviews.llvm.org/D82668
2020-06-29 16:48:53 +00:00
Aaron Ballman 37657991d1 Fix a crash with [[clang::acquire_handle]] when written as a type
attribute with no arguments provided.
2020-06-25 08:45:32 -04:00
Florian Hahn 043b608399 [Matrix] Use 1st/2nd instead of first/second in matrix diags.
This was suggested in D72782 and brings the diagnostics more in line
with how argument references are handled elsewhere.

Reviewers: rjmccall, jfb, Bigcheese

Reviewed By: rjmccall

Differential Revision: https://reviews.llvm.org/D82473
2020-06-25 11:55:03 +01:00
Mikhail Maltsev 3f353a2e5a [BFloat] Add convert/copy instrinsic support
This patch is part of a series implementing the Bfloat16 extension of the Armv8.6-a architecture, as detailed here:

https://community.arm.com/developer/ip-products/processors/b/processors-ip-blog/posts/arm-architecture-developments-armv8-6-a

Specifically it adds intrinsic support in clang and llvm for Arm and AArch64.

The bfloat type, and its properties are specified in the Arm Architecture Reference Manual:

https://developer.arm.com/docs/ddi0487/latest/arm-architecture-reference-manual-armv8-for-armv8-a-architecture-profile

The following people contributed to this patch:
  - Alexandros Lamprineas
  - Luke Cheeseman
  - Mikhail Maltsev
  - Momchil Velikov
  - Luke Geeson

Differential Revision: https://reviews.llvm.org/D80928
2020-06-23 14:27:05 +00:00
Zhi Zhuang 37fb860301 Add support of __builtin_expect_with_probability
Add a new builtin-function __builtin_expect_with_probability and
intrinsic llvm.expect.with.probability.
The interface is __builtin_expect_with_probability(long expr, long
expected, double probability).
It is mainly the same as __builtin_expect besides one more argument
indicating the probability of expression equal to expected value. The
probability should be a constant floating-point expression and be in
range [0.0, 1.0] inclusive.
It is similar to builtin-expect-with-probability function in GCC
built-in functions.

Differential Revision: https://reviews.llvm.org/D79830
2020-06-22 10:21:28 -07:00
Benson Chu c310bf8256 [Sema] Comparison of pointers to complete and incomplete types
Clang is missing one of the conditions for C99 6.5.9p2, where comparison
between pointers must either both point to incomplete types or both
point to complete types. This patch adds an extra check to the clause
where two pointers are of compatible types.

This only applies to C89/C99; the relevant part of the standard was
rewritten for C11.

Differential Revision: https://reviews.llvm.org/D79945
2020-06-19 17:01:03 -07:00
Florian Hahn b5e082e728 [Matrix] Add __builtin_matrix_column_store to Clang.
This patch add __builtin_matrix_column_major_store to Clang,
as described in clang/docs/MatrixTypes.rst. In the initial version,
the stride is not optional yet.

Reviewers: rjmccall, jfb, rsmith, Bigcheese

Reviewed By: rjmccall

Differential Revision: https://reviews.llvm.org/D72782
2020-06-18 11:39:02 +01:00
Florian Hahn 934bcaf10b [Matrix] Add __builtin_matrix_column_load to Clang.
This patch add __builtin_matrix_column_major_load to Clang,
as described in clang/docs/MatrixTypes.rst. In the initial version,
the stride is not optional yet.

Reviewers: rjmccall, rsmith, jfb, Bigcheese

Reviewed By: rjmccall

Differential Revision: https://reviews.llvm.org/D72781
2020-06-18 10:47:55 +01:00
Guillaume Chatelet 12c8e3632e [Clang][Sema] Use of incorrect __has_feature vs __has_builtin 2020-06-18 09:00:12 +00:00
Luke Geeson 508a4764c0 [AArch64]: BFloat Load/Store Intrinsics&CodeGen
This patch upstreams support for ld / st variants of BFloat intrinsics
in from __bf16 to AArch64. This includes IR intrinsics. Unittests are
provided as needed.

This patch is part of a series implementing the Bfloat16 extension of
the
Armv8.6-a architecture, as detailed here:

https://community.arm.com/developer/ip-products/processors/b/processors-ip-blog/posts/arm-architecture-developments-armv8-6-a

The bfloat type, and its properties are specified in the Arm
Architecture
Reference Manual:

https://developer.arm.com/docs/ddi0487/latest/arm-architecture-reference-manual-armv8-for-armv8-a-architecture-profile

The following people contributed to this patch:

 - Luke Geeson
 - Momchil Velikov
 - Luke Cheeseman

Reviewers: fpetrogalli, SjoerdMeijer, sdesmalen, t.p.northover, stuij

Reviewed By: stuij

Subscribers: arsenm, pratlucas, simon_tatham, labrinea, kristof.beyls,
hiraditya, danielkiss, cfe-commits, llvm-commits, pbarrio, stuij

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D80716

Change-Id: I22e1dca2a8a9ec25d1e4f4b200cb50ea493d2575
2020-06-16 15:23:30 +01:00
Haojian Wu 28923dc2dd [AST][RecoveryExpr] Fix a crash on a field decl with invalid type.
Summary:
The field decl (in the testcase) was still valid, which results in a
valid RecordDecl, it led to crash when performing struct layout,
and computing struct size etc.

Reviewers: sammccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D81913
2020-06-16 12:12:10 +02:00
Jeff Mott 8799ebbc1f [clang] Fix or emit diagnostic for checked arithmetic builtins with
_ExtInt types

- Fix computed size for _ExtInt types passed to checked arithmetic
  builtins.
- Emit diagnostic when signed _ExtInt larger than 128-bits is passed
    to __builtin_mul_overflow.
- Change Sema checks for builtins to accept placeholder types.

Differential Revision: https://reviews.llvm.org/D81420
2020-06-15 06:51:54 -07:00
Vy Nguyen a21a462051 Make the diagnostic-missing-prototypes put the suggested `static` in front of `const` if exists.
Summary:
Consider: `const int* get_foo() {return nullptr;}`
The suggested fix should be `static const int* get_foo(){}`
and not `const static int* get_foo(){}`

Reviewers: gribozavr2

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D81444
2020-06-09 19:34:57 -04:00
Erich Keane 113b0d7d0b PR46255: Fix field diagnostics for C records with anonymous members.
The ParseStructUnionBody function was separately keeping track of the
field decls for historical reasons, however the "ActOn" functions add
the field to the RecordDecl anyway.

The "ParseStructDeclaration" function, which handles parsing fields
didn't have a way of handling what happens on an anonymous field, and
changing it would alter a large amount of objc code, so I chose instead
to implement this by just filling the FieldDecls vector with the actual
FieldDecls that were successfully added to the recorddecl .
2020-06-09 12:27:44 -07:00
Saiyedul Islam 675cefbf60 [AMDGPU] Introduce Clang builtins to be mapped to AMDGCN atomic inc/dec intrinsics
Summary:
__builtin_amdgcn_atomic_inc32(int *Ptr, int Val, unsigned MemoryOrdering, const char *SyncScope)
__builtin_amdgcn_atomic_inc64(int64_t *Ptr, int64_t Val, unsigned MemoryOrdering, const char *SyncScope)
__builtin_amdgcn_atomic_dec32(int *Ptr, int Val, unsigned MemoryOrdering, const char *SyncScope)
__builtin_amdgcn_atomic_dec64(int64_t *Ptr, int64_t Val, unsigned MemoryOrdering, const char *SyncScope)

First and second arguments gets transparently passed to the amdgcn atomic
inc/dec intrinsic. Fifth argument of the intrinsic is set as true if the
first argument of the builtin is a volatile pointer. The third argument of
this builtin is one of the memory-ordering specifiers ATOMIC_ACQUIRE,
ATOMIC_RELEASE, ATOMIC_ACQ_REL, or ATOMIC_SEQ_CST following C++11 memory
model semantics. This is mapped to corresponding LLVM atomic memory ordering
for the atomic inc/dec instruction using CLANG atomic C ABI. The fourth
argument is an AMDGPU-specific synchronization scope defined as string.

Reviewers: arsenm, sameerds, JonChesterfield, jdoerfert

Reviewed By: arsenm, sameerds

Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, jfb, kerbowa, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D80804
2020-06-09 17:02:58 +00:00
Florian Hahn 3323a628ec [Matrix] Add __builtin_matrix_transpose to Clang.
This patch add __builtin_matrix_transpose to Clang, as described in
clang/docs/MatrixTypes.rst.

Reviewers: rjmccall, jfb, rsmith, Bigcheese

Reviewed By: rjmccall

Differential Revision: https://reviews.llvm.org/D72778
2020-06-09 10:14:37 +01:00
Fangrui Song fc935fc35b Reland D80979 [clang] Implement VectorType logic not operator
With a fix to use -triple %itanium_abi_triple

Differential Revision: https://reviews.llvm.org/D80979
2020-06-08 09:32:30 -07:00
Aaron Puchert f70912f885 Thread safety analysis: Add note for double unlock
Summary:
When getting a warning that we release a capability that isn't held it's
sometimes not clear why. So just like we do for double locking, we add a
note on the previous release operation, which marks the point since when
the capability isn't held any longer.

We can find this previous release operation by looking up the
corresponding negative capability.

Reviewers: aaron.ballman, delesley

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D81352
2020-06-08 17:00:29 +02:00
Nico Weber abca3b7b2c Revert "[clang] Implement VectorType logic not operator."
This reverts commit a0de3335ed.
Breaks check-clang on Windows, see e.g.
https://reviews.llvm.org/D80979#2078750 (but fails on all
other Windows bots too).
2020-06-08 06:45:21 -04:00
Jun Ma a0de3335ed [clang] Implement VectorType logic not operator.
Differential Revision: https://reviews.llvm.org/D80979
2020-06-08 08:41:01 +08:00
Florian Hahn 4affc444b4 [Matrix] Implement * binary operator for MatrixType.
This patch implements the * binary operator for values of
MatrixType. It adds support for matrix * matrix, scalar * matrix and
matrix * scalar.

For the matrix, matrix case, the number of columns of the first operand
must match the number of rows of the second. For the scalar,matrix variants,
the element type of the matrix must match the scalar type.

Reviewers: rjmccall, anemet, Bigcheese, rsmith, martong

Reviewed By: rjmccall

Differential Revision: https://reviews.llvm.org/D76794
2020-06-07 11:11:27 +01:00
Dan Gohman 0d4e243456 [WebAssembly] Improve clang diagnostics for wasm attributes
This patch addresses the review comments on r352930:

 - Removes redundant diagnostic checking code
 - Removes errnoneous use of diag::err_alias_is_definition, which
   turned out to be ineffective anyway since functions can be defined later
   in the translation unit and avoid detection.
 - Adds a test for various invalid cases for import_name and import_module.

This reapplies D59520, with the addition of adding
`InGroup<IgnoredAttributes>` to the new warnings, to fix the
Misc/warning-flags.c failure.

Differential Revision: https://reviews.llvm.org/D59520
2020-06-05 14:32:51 -07:00
Dan Gohman 3aec298349 Revert "[WebAssembly] Improve clang diagnostics for wasm attributes"
It broke clang-check.

This reverts commit 931fcd3ba0.
2020-06-05 11:52:11 -07:00
Dan Gohman 931fcd3ba0 [WebAssembly] Improve clang diagnostics for wasm attributes
This patch addresses the review comments on r352930:

 - Removes redundant diagnostic checking code
 - Removes errnoneous use of diag::err_alias_is_definition, which
   turned out to be ineffective anyway since functions can be defined later
   in the translation unit and avoid detection.
 - Adds a test for various invalid cases for import_name and import_module.

Differential Revision: https://reviews.llvm.org/D59520
2020-06-05 11:27:51 -07:00
Ties Stuij ecd682bbf5 [ARM] Add __bf16 as new Bfloat16 C Type
Summary:
This patch upstreams support for a new storage only bfloat16 C type.
This type is used to implement primitive support for bfloat16 data, in
line with the Bfloat16 extension of the Armv8.6-a architecture, as
detailed here:

https://community.arm.com/developer/ip-products/processors/b/processors-ip-blog/posts/arm-architecture-developments-armv8-6-a

The bfloat type, and its properties are specified in the Arm Architecture
Reference Manual:

https://developer.arm.com/docs/ddi0487/latest/arm-architecture-reference-manual-armv8-for-armv8-a-architecture-profile

In detail this patch:
- introduces an opaque, storage-only C-type __bf16, which introduces a new bfloat IR type.

This is part of a patch series, starting with command-line and Bfloat16
assembly support. The subsequent patches will upstream intrinsics
support for BFloat16, followed by Matrix Multiplication and the
remaining Virtualization features of the armv8.6-a architecture.

The following people contributed to this patch:
- Luke Cheeseman
- Momchil Velikov
- Alexandros Lamprineas
- Luke Geeson
- Simon Tatham
- Ties Stuij

Reviewers: SjoerdMeijer, rjmccall, rsmith, liutianle, RKSimon, craig.topper, jfb, LukeGeeson, fpetrogalli

Reviewed By: SjoerdMeijer

Subscribers: labrinea, majnemer, asmith, dexonsmith, kristof.beyls, arphaman, danielkiss, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D76077
2020-06-05 10:32:43 +01:00
Min-Yih Hsu 4431d64c10 Support ExtVectorType conditional operator
Extension vectors now can be used in element-wise conditional selector.
For example:
```
R[i] = C[i]? A[i] : B[i]
```
This feature was previously only enabled in OpenCL C. Now it's also
available in C. Not that it has different behaviors than GNU vectors
(i.e. __vector_size__). Extension vectors selects on signdness of the
vector. GNU vectors on the other hand do normal bool conversions. Also,
this feature is not available in C++.

Differential Revision: https://reviews.llvm.org/D80574
2020-06-02 16:35:42 +00:00
Florian Hahn 8f3f88d2f5 [Matrix] Implement matrix index expressions ([][]).
This patch implements matrix index expressions
(matrix[RowIdx][ColumnIdx]).

It does so by introducing a new MatrixSubscriptExpr(Base, RowIdx, ColumnIdx).
MatrixSubscriptExprs are built in 2 steps in ActOnMatrixSubscriptExpr. First,
if the base of a subscript is of matrix type, we create a incomplete
MatrixSubscriptExpr(base, idx, nullptr). Second, if the base is an incomplete
MatrixSubscriptExpr, we create a complete
MatrixSubscriptExpr(base->getBase(), base->getRowIdx(), idx)

Similar to vector elements, it is not possible to take the address of
a MatrixSubscriptExpr.
For CodeGen, a new MatrixElt type is added to LValue, which is very
similar to VectorElt. The only difference is that we may need to cast
the type of the base from an array to a vector type when accessing it.

Reviewers: rjmccall, anemet, Bigcheese, rsmith, martong

Reviewed By: rjmccall

Differential Revision: https://reviews.llvm.org/D76791
2020-06-01 20:08:49 +01:00
Aaron Ballman 522934da1f Support GCC [[gnu::attributes]] in C2x mode
GCC 10.1 introduced support for the [[]] style spelling of attributes in C
mode. Similar to how GCC supports __attribute__((foo)) as [[gnu::foo]] in
C++ mode, it now supports the same spelling in C mode as well. This patch
makes a change in Clang so that when you use the GCC attribute spelling,
the attribute is automatically available in all three spellings by default.
However, like Clang, GCC has some attributes it only recognizes in C++ mode
(specifically, abi_tag and init_priority), which this patch also honors.
2020-06-01 10:42:42 -04:00
Florian Hahn 6f6e91d193 [Matrix] Implement + and - operators for MatrixType.
This patch implements the + and - binary operators for values of
MatrixType. It adds support for matrix +/- matrix, scalar +/- matrix and
matrix +/- scalar.

For the matrix, matrix case, the types must initially be structurally
equivalent. For the scalar,matrix variants, the element type of the
matrix must match the scalar type.

Reviewers: rjmccall, anemet, Bigcheese, rsmith, martong

Reviewed By: rjmccall

Differential Revision: https://reviews.llvm.org/D76793
2020-05-29 20:42:22 +01:00
Haojian Wu 82bb57c11d [AST][RecoveryExpr] Make DeduceAutoType fail if the auto is deduced from recovery exprs.
Summary:
With recovery-ast, we will get an undeduced `auto` return type for
"auto foo()->undef()" function declaration, the function decl still keeps
valid, it is dangerous, and breaks assumptions in clang, and leads crashes.

This patch invalidates these functions, if we deduce autos from the
return rexpression, which is similar to auto VarDecl.

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D80221
2020-05-29 09:54:28 +02:00
Nemanja Ivanovic 9021ce9576 [Clang] Enable KF and KC mode for [_Complex] __float128
The headers provided with recent GNU toolchains for PPC have code that includes
typedefs such as:

typedef _Complex float __cfloat128 __attribute__ ((__mode__ (__KC__)))

This patch allows clang to compile programs that contain
#include <math.h>

with -mfloat128 which it currently fails to compile.

Fixes: https://bugs.llvm.org/show_bug.cgi?id=46068

Differential revision: https://reviews.llvm.org/D80374
2020-05-28 15:48:15 -05:00
Dmitry Preobrazhensky 3c6c2ecd6e [AMDGPU] Added 'A' constraint for inline assembler
Summary: 'A' constraint requires an immediate int or fp constant that can be inlined in an instruction encoding.
This is the second part of the change. The llvm part has been committed as b087b91c91.
See https://reviews.llvm.org/D78494

Reviewers: arsenm, rampitec

Differential Revision: https://reviews.llvm.org/D79493
2020-05-25 17:47:06 +03:00
Alexey Bader e95ee300c0 [SYCL] Prohibit arithmetic operations for incompatible pointers
Summary:
This change enables OpenCL diagnostics for the pointers annotated with
address space attribute SYCL mode.

Move `isAddressSpaceOverlapping` method from PointerType to QualType.

Reviewers: Anastasia, rjmccall

Reviewed By: rjmccall

Subscribers: rjmccall, jeroen.dobbelaere, Fznamznon, yaxunl, ebevhan, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D80317
2020-05-22 13:43:24 +03:00
Zequan Wu e36076ee3a [clang] Add nomerge function attribute to clang
Differential Revision: https://reviews.llvm.org/D79121
2020-05-21 17:07:39 -07:00
Zequan Wu b0a0f01bc1 Revert "Add nomerge function attribute to clang"
This reverts commit 307e853954.
2020-05-21 16:13:18 -07:00
Zequan Wu 307e853954 Add nomerge function attribute to clang 2020-05-21 15:28:27 -07:00
Erich Keane 81a73fde5c Fix aux-target diagnostics for certain builtins
When I fixed the targets specific builtins to make sure that aux-targets
are checked, it seems I didn't consider cases where the builtins check
the target info for further info.  This patch bubbles the target-info
down to the individual checker functions to ensure that they validate
against the aux-target as well.

For non-aux-target invocations, this is an NFC.
2020-05-19 10:49:45 -07:00
Yonghong Song 072cde03aa [Clang][BPF] implement __builtin_btf_type_id() builtin function
Such a builtin function is mostly useful to preserve btf type id
for non-global data. For example,
   extern void foo(..., void *data, int size);
   int test(...) {
     struct t { int a; int b; int c; } d;
     d.a = ...; d.b = ...; d.c = ...;
     foo(..., &d, sizeof(d));
   }

The function "foo" in the above only see raw data and does not
know what type of the data is. In certain cases, e.g., logging,
the additional type information will help pretty print.

This patch implemented a BPF specific builtin
  u32 btf_type_id = __builtin_btf_type_id(param, flag)
which will return a btf type id for the "param".
flag == 0 will indicate a BTF local relocation,
which means btf type_id only adjusted when bpf program BTF changes.
flag == 1 will indicate a BTF remote relocation,
which means btf type_id is adjusted against linux kernel or
future other entities.

Differential Revision: https://reviews.llvm.org/D74668
2020-05-15 09:44:54 -07:00
Erich Keane f9eaa6934e Ensure aux-target specific builtins get validated.
I discovered that when using an aux-target builtin, it was recognized as
a builtin but never checked. This patch checks for an aux-target builtin
and instead validates it against the correct target.

It does this by extracting the checking code for Target-specific
builtins into its own function, then calls with either targetInfo or
AuxTargetInfo.
2020-05-07 13:22:10 -07:00
Lucas Prates 9d39df03a9 [Clang][Sema] Capturing section type conflicts between #pragma clang section and section attributes
Summary:
Conflicting types for the same section name defined in clang section
pragmas and GNU-style section attributes were not properly captured by
Clang's Sema. The lack of diagnostics was caused by the fact the section
specification coming from attributes was handled by Sema as implicit,
even though explicitly defined by the user.

This patch enables the diagnostics for section type conflicts between
those specifications by making sure sections defined in section
attributes are correctly handled as explicit.

Reviewers: hans, rnk, javed.absar

Reviewed By: rnk

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D78573
2020-05-07 11:54:46 +01:00
Lucas Prates 0dac639f28 [Clang][Sema] Capturing section type conflicts on #pragma clang section
Summary:
Section names used in clang section pragmas were not validated against
previously defined sections, causing section type conflicts to be
ignored by Sema.

This patch enables Clang to capture these section type conflicts by
using the existing Sema's UnifySection method to validate section names
from clang section pragmas.

Reviewers: hans, rnk, javed.absar

Reviewed By: rnk

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D78572
2020-05-07 11:53:30 +01:00
Fangrui Song 57a1c1be53 [Sema] Allow function attribute patchable_function_entry on aarch64_be
Reviewed By: nickdesaulniers

Differential Revision: https://reviews.llvm.org/D79495
2020-05-06 10:10:25 -07:00
Erich Keane 8a1c999c9b Implement _ExtInt ABI for all ABIs in Clang, enable type for ABIs
This is the result of an audit of all of the ABIs in clang to implement
and enable the type for those targets.

Additionally, this finds an issue with integer-promotion passing for a
few platforms when using _ExtInt of < int, so this also corrects that
resulting in signext/zeroext being on a params of those types in some
platforms.

Differential Revisions: https://reviews.llvm.org/D79118
2020-05-06 06:52:18 -07:00
Richard Sandiford 69ab8b46b8 [Sema][SVE] Fix handling of initialisers for built-in SVE types
The built-in SVE types are supposed to be treated as opaque types.
This means that for initialisation purposes they should be treated
as a single unit, much like a scalar type.

However, as Eli pointed out, actually using "scalar" in the diagnostics
is likely to cause confusion, given the types are logically vectors.
The patch therefore uses custom diagnostics or generalises existing
ones.  Some of the messages use the word "indivisible" to try to make
it clear(er) that these types can't be initialised elementwise.

I don't think it's possible to trigger warn_braces_around_(scalar_)init
for sizeless types as things stand, since the types can't be used as
members or elements of more complex types.  But it seemed better to be
consistent with ext_many_braces_around_(scalar_)init, so the patch
changes it anyway.

Differential Revision: https://reviews.llvm.org/D76689
2020-05-06 12:24:27 +01:00
Richard Sandiford e959931092 [Sema] Put existing warning under -Wexcess-initializers
I have a follow-on patch that uses an alternative wording for
ext_excess_initializers in some cases.  This patch puts it and
a couple of related warnings under their own -W option in order
to avoid a regression in Misc/warning-flags.c.

Differential Revision: https://reviews.llvm.org/D79244
2020-05-06 11:28:40 +01:00
Erich Keane 911add149a Disable _ExtInt by default
Since the _ExtInt type got into the repo, we've discovered that the ABI
implications weren't completely understood. The other architectures are
going to be audited (see D79118), however downstream targets aren't
going to benefit from this audit.

This patch disables the _ExtInt type by default and makes the
target-info an opt-in.  As it is audited, I'll re-enable these for all
of our default targets.
2020-04-29 13:48:12 -07:00
Momchil Velikov 102b4105e3 [CMSE] Clear padding bits of struct/unions/fp16 passed by value
When passing a value of a struct/union type from secure to non-secure
state (that is returning from a CMSE entry function or passing an
argument to CMSE-non-secure call), there is a potential sensitive
information leak via the padding bits in the structure. It is not
possible in the general case to ensure those bits are cleared by using
Standard C/C++.

This patch makes the compiler emit code to clear such padding
bits. Since type information is lost in LLVM IR, the code generation
is done by Clang.

For each interesting record type, we build a bitmask, in which all the
bits, corresponding to user declared members, are set. Values of
record types are returned by coercing them to an integer. After the
coercion, the coerced value is masked (with bitwise AND) and then
returned by the function. In a similar manner, values of record types
are passed as arguments by coercing them to an array of integers, and
the coerced values themselves are masked.

For union types, we effectively clear only bits, which aren't part of
any member, since we don't know which is the currently active one.
The compiler will issue a warning, whenever a union is passed to
non-secure state.

Values of half-precision floating-point types are passed in the least
significant bits of a 32-bit register (GPR or FPR) with the most
significant bits unspecified. Since this is also a potential leak of
sensitive information, this patch also clears those unspecified bits.

Differential Revision: https://reviews.llvm.org/D76369
2020-04-28 17:05:58 +01:00
Dmitri Gribenko 0d69e412c4 Explicitly tell Clang to output to stdout in a test that runs FileCheck 2020-04-27 10:13:28 +02:00
Saiyedul Islam 06bdffb2bb [AMDGPU] Expose llvm fence instruction as clang intrinsic
Expose llvm fence instruction as clang builtin for AMDGPU target

__builtin_amdgcn_fence(unsigned int memoryOrdering, const char *syncScope)

The first argument of this builtin is one of the memory-ordering specifiers
__ATOMIC_ACQUIRE, __ATOMIC_RELEASE, __ATOMIC_ACQ_REL, or __ATOMIC_SEQ_CST
following C++11 memory model semantics. This is mapped to corresponding
LLVM atomic memory ordering for the fence instruction using LLVM atomic C
ABI. The second argument is an AMDGPU-specific synchronization scope
defined as string.

Reviewed By: sameerds

Differential Revision: https://reviews.llvm.org/D75917
2020-04-27 09:39:03 +05:30
Fangrui Song 2c3ee8812c [Sema][test] Fix implicit-int-float-conversion.c on Windows 2020-04-23 18:52:04 -07:00
Fangrui Song 14aaf4457c [Sema] Split off warn_impcast_integer_float_precision_constant into -Wimplicit-const-int-float-conversion
Currently, both `warn_impcast_integer_float_precision_constant` and
`warn_impcast_integer_float_precision` are covered by
-Wimplicit-int-float-conversion, but only the ..._constant warning is on
by default.

`warn_impcast_integer_float_precision_constant` likely flags real problems
while `warn_impcast_integer_float_precision` may flag legitimate use
cases (for example, `int` used with limited range supported by `float`).

If -Wno-implicit-int-float-conversion is used, currently there is no way
to restore the ..._constant warning. This patch adds
-Wimplicit-const-int-float-conversion to address the issue. (Similar to
the reasoning in https://reviews.llvm.org/D64666#1598194)

Adapted from a patch by Brooks Moses.

Reviewed By: nickdesaulniers

Differential Revision: https://reviews.llvm.org/D78661
2020-04-23 18:26:06 -07:00
David Green eecba95067 [ARM] Replace arm vendor with none. NFC 2020-04-22 18:19:35 +01:00
Jon Roelofs 38b39c34ab [clang] Add missing FileCheck colons 2020-04-14 12:32:48 -06:00
Aaron Ballman 86b5eabfea Allow parameter names to be elided in a function definition in C.
WG14 has adopted N2480 (http://www.open-std.org/jtc1/sc22/wg14/www/docs/n2480.pdf)
into C2x at the meetings last week, allowing parameter names of a function
definition to be elided. This patch relaxes the error so that C++ and C2x do not
diagnose this situation, and modes before C2x will allow it as an extension.

This also adds the same feature to ObjC blocks under the assumption that ObjC
wishes to follow the C standard in this regard.
2020-04-07 14:43:38 -04:00
Sam McCall 88fbadd0f5 [AST] clang::VectorType supports any size (that fits in unsigned)
Summary:
This matches llvm::VectorType.
It moves the size from the type bitfield into VectorType, increasing size by 8
bytes (including padding of 4). This is OK as we don't expect to create terribly
many of these types.

c.f. D77313 which enables large power-of-two sizes without growing VectorType.

Reviewers: efriedma, hokein

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D77335
2020-04-03 17:30:31 +02:00
Fangrui Song d0d076fed9 [Driver] Flip the CC1 default of -fdiagnostics-show-option
The driver enables -fdiagnostics-show-option by default, so flip the CC1
default to reduce the lengths of common CC1 command lines.

This change also makes ParseDiagnosticArgs() consistently enable
-fdiagnostics-show-option by default.
2020-03-31 21:59:27 -07:00
Haojian Wu 6f428e09fb [AST] Fix crashes on decltype(recovery-expr).
Summary: We mark these decls as invalid.

Reviewers: sammccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D77037
2020-03-30 14:56:33 +02:00
Haojian Wu f757ecbf85 [AST] Fix a crash on invalid bitwidth exprs when preserving the recoveryexprs.
Summary:
If the bitwith expr contains errors, we mark the field decl invalid.

This patch also tweaks the behavior of ObjCInterfaceDecl to be consistent with
existing RecordDecl -- getObjCLayout method is only called with valid decls.

Reviewers: sammccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D76953
2020-03-30 10:52:00 +02:00
Sam McCall 47e7bdb107 Test that would have caught recovery-expr crashes in 0788acbccb. NFC 2020-03-26 18:43:29 +01:00
Richard Sandiford 856bdd01fd [Sema][SVE] Allow casting SVE types to themselves in C
Casts from an SVE type to itself aren't very useful, but they are
supposed to be valid, and could occur in things like macro expansions.

Such casts already work for C++ and are tested by sizeless-1.cpp.
This patch makes them work for C too.

Differential Revision: https://reviews.llvm.org/D76694
2020-03-25 10:52:43 +00:00
Richard Sandiford 578fb2501a [Sema][SVE] Allow ?: to select between SVE types in C
When compiling C, a ?: between two values of the same SVE type
currently gives an error such as:

  incompatible operand types ('svint8_t' (aka '__SVInt8_t') and 'svint8_t')

It's supposed to be valid to select between (cv-qualified versions of)
the same SVE type, so this patch adds that case.

These expressions already work for C++ and are tested by
SemaCXX/sizeless-1.cpp.

Differential Revision: https://reviews.llvm.org/D76693
2020-03-25 10:31:09 +00:00
Momchil Velikov 080d046c91 [ARM][CMSE] Implement CMSE attributes
This patch adds CMSE attributes `cmse_nonsecure_call` and
`cmse_nonsecure_entry`.  As usual, specification is available here:
https://developer.arm.com/docs/ecm0359818/latest

Patch by Javed Absar, Bradley Smith, David Green, Momchil Velikov,
possibly others.

Differential Revision: https://reviews.llvm.org/D71129
2020-03-24 10:21:26 +00:00
Momchil Velikov 6081ccf4a3 Apply function attributes through array declarators
There's inconsistency in handling array types between the
`distributeFunctionTypeAttrXXX` functions and the
`FunctionTypeUnwrapper` in `SemaType.cpp`.

This patch lets `FunctionTypeUnwrapper` apply function type attributes
through array types.

Differential Revision: https://reviews.llvm.org/D75109
2020-03-23 11:03:13 +00:00
Guillaume Chatelet d260a10d98 [clang] Fix crash during template sema checking
Summary: If the size parameter of `__builtin_memcpy_inline` comes from an un-instantiated template parameter current code would crash.

Reviewers: efriedma, courbet

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D76504
2020-03-21 12:42:06 +01:00
Mikhail Maltsev 969034b860 [ARM,CDE] Implement CDE unpredicated Q-register intrinsics
Summary:
This patch implements the following intrinsics:

  uint8x16_t __arm_vcx1q_u8 (int coproc, uint32_t imm);
  T __arm_vcx1qa(int coproc, T acc, uint32_t imm);
  T __arm_vcx2q(int coproc, T n, uint32_t imm);
  uint8x16_t __arm_vcx2q_u8(int coproc, T n, uint32_t imm);
  T __arm_vcx2qa(int coproc, T acc, U n, uint32_t imm);
  T __arm_vcx3q(int coproc, T n, U m, uint32_t imm);
  uint8x16_t __arm_vcx3q_u8(int coproc, T n, U m, uint32_t imm);
  T __arm_vcx3qa(int coproc, T acc, U n, V m, uint32_t imm);

Most of them are polymorphic. Furthermore, some intrinsics are
polymorphic by 2 or 3 parameter types, such polymorphism is not
supported by the existing MVE/CDE tablegen backends, also we don't
really want to have a combinatorial explosion caused by 1000 different
combinations of 3 vector types. Because of this some intrinsics are
implemented as macros involving a cast of the polymorphic arguments to
uint8x16_t.

The IR intrinsics are even more restricted in terms of types: all MVE
vectors are cast to v16i8.

Reviewers: simon_tatham, MarkMurrayARM, dmgreen, ostannard

Reviewed By: MarkMurrayARM

Subscribers: kristof.beyls, hiraditya, danielkiss, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D76299
2020-03-20 14:01:56 +00:00
Mikhail Maltsev d22e661712 [ARM,CDE] Implement CDE S and D-register intrinsics
Summary:
This patch implements the following ACLE intrinsics:

  uint32_t __arm_vcx1_u32(int coproc, uint32_t imm);
  uint32_t __arm_vcx1a_u32(int coproc, uint32_t acc, uint32_t imm);
  uint32_t __arm_vcx2_u32(int coproc, uint32_t n, uint32_t imm);
  uint32_t __arm_vcx2a_u32(int coproc, uint32_t acc, uint32_t n, uint32_t imm);
  uint32_t __arm_vcx3_u32(int coproc, uint32_t n, uint32_t m, uint32_t imm);
  uint32_t __arm_vcx3a_u32(int coproc, uint32_t acc, uint32_t n, uint32_t m, uint32_t imm);

  uint64_t __arm_vcx1d_u64(int coproc, uint32_t imm);
  uint64_t __arm_vcx1da_u64(int coproc, uint64_t acc, uint32_t imm);
  uint64_t __arm_vcx2d_u64(int coproc, uint64_t m, uint32_t imm);
  uint64_t __arm_vcx2da_u64(int coproc, uint64_t acc, uint64_t m, uint32_t imm);
  uint64_t __arm_vcx3d_u64(int coproc, uint64_t n, uint64_t m, uint32_t imm);
  uint64_t __arm_vcx3da_u64(int coproc, uint64_t acc, uint64_t n, uint64_t m, uint32_t imm);

Since the semantics of CDE instructions is opaque to the compiler, the
ACLE intrinsics require dedicated LLVM IR intrinsics. The 64-bit and
32-bit variants share the same IR intrinsic.

Reviewers: simon_tatham, MarkMurrayARM, ostannard, dmgreen

Reviewed By: MarkMurrayARM

Subscribers: kristof.beyls, hiraditya, danielkiss, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D76298
2020-03-20 14:01:53 +00:00
Mikhail Maltsev 7a85e3585e [ARM,CDE] Implement GPR CDE intrinsics
Summary:
This change implements ACLE CDE intrinsics that translate to
instructions working with general-purpose registers.

The specification is available at
https://static.docs.arm.com/101028/0010/ACLE_2019Q4_release-0010.pdf

Each ACLE intrinsic gets a corresponding LLVM IR intrinsic (because
they have distinct function prototypes). Dual-register operands are
represented as pairs of i32 values. Because of this the instruction
selection for these intrinsics cannot be represented as TableGen
patterns and requires custom C++ code.

Reviewers: simon_tatham, MarkMurrayARM, dmgreen, ostannard

Reviewed By: MarkMurrayARM

Subscribers: kristof.beyls, hiraditya, danielkiss, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D76296
2020-03-20 14:01:51 +00:00
Jon Chesterfield c45eaeabb7 [Clang] Undef attribute for global variables
Summary:
[Clang] Attribute to allow defining undef global variables

Initializing global variables is very cheap on hosted implementations. The
C semantics of zero initializing globals work very well there. It is not
necessarily cheap on freestanding implementations. Where there is no loader
available, code must be emitted near the start point to write the appropriate
values into memory.

At present, external variables can be declared in C++ and definitions provided
in assembly (or IR) to achive this effect. This patch provides an attribute in
order to remove this reason for writing assembly for performance sensitive
freestanding implementations.

A close analogue in tree is LDS memory for amdgcn, where the kernel is
responsible for initializing the memory after it starts executing on the gpu.
Uninitalized variables in LDS are observably cheaper than zero initialized.

Patch is loosely based on the cuda __shared__ and opencl __local variable
implementation which also produces undef global variables.

Reviewers: kcc, rjmccall, rsmith, glider, vitalybuka, pcc, eugenis, vlad.tsyrklevich, jdoerfert, gregrodgers, jfb, aaron.ballman

Reviewed By: rjmccall, aaron.ballman

Subscribers: Anastasia, aaron.ballman, davidb, Quuxplusone, dexonsmith, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D74361
2020-03-17 21:22:23 +00:00
Richard Sandiford 94489f35a7 [Sema][SVE] Reject arithmetic on pointers to sizeless types
This patch completes a trio of changes related to arrays of
sizeless types.  It rejects various forms of arithmetic on
pointers to sizeless types, in the same way as for other
incomplete types.

Differential Revision: https://reviews.llvm.org/D76086
2020-03-17 11:35:20 +00:00
Richard Sandiford 010005f077 [Sema][SVE] Reject subscripts on pointers to sizeless types
clang currently accepts:

  __SVInt8_t &foo1(__SVInt8_t *x) { return *x; }
  __SVInt8_t &foo2(__SVInt8_t *x) { return x[1]; }

The first function is valid ACLE code and generates correct LLVM IR
(and assembly code).  But the second function is invalid for the
same reason that arrays of sizeless types are.  Trying to code-generate
the function leads to:

  llvm/include/llvm/Support/TypeSize.h:126: uint64_t llvm::TypeSize::getFixedSize() const: Assertion `!IsScalable && "Request for a fixed size on a s
calable object"' failed.

Another problem is that:

  template<typename T>
  constexpr __SIZE_TYPE__ f(T *x) { return &x[1] - x; }
  typedef int arr1[f((int *)0) - 1];
  typedef int arr2[f((__SVInt8_t *)0) - 1];

produces:

  a.cpp:2:48: warning: subtraction of pointers to type '__SVInt8_t' of zero size has undefined behavior [-Wpointer-arith]
  constexpr __SIZE_TYPE__ f(T *x) { return &x[1] - x; }
					   ~~~~~ ^ ~
  a.cpp:4:18: note: in instantiation of function template specialization 'f<__SVInt8_t>' requested here
  typedef int arr2[f((__SVInt8_t *)0) - 1];

This patch reports an appropriate diagnostic instead.

Differential Revision: https://reviews.llvm.org/D76084
2020-03-17 11:24:57 +00:00
Aaron Ballman dab43c8592 Remove some explicit calls to getName() when printing diagnostics; NFC 2020-03-14 17:01:45 -04:00
Richard Sandiford 994c071a1b [Sema][SVE] Reject arrays of sizeless types
The SVE ACLE doesn't allow arrays of sizeless types.  At the moment
clang accepts the TU:

  __SVInt8_t x[2];

but trying to code-generate it triggers the LLVM assertion:

  llvm/lib/IR/Type.cpp:588: static llvm::ArrayType* llvm::ArrayType::get(llvm::Type*, uint64_t): Assertion `isValidElementType(ElementType) && "Invalid type for array element!"' failed.

This patch reports an appropriate error instead.

The rules are slightly more restrictive than for general incomplete types.
For example:

  struct s;
  typedef struct s arr[2];

is valid as far as it goes, whereas arrays of sizeless types are
invalid in all contexts.  BuildArrayType therefore needs a specific
check for isSizelessType in addition to the usual handling of
incomplete types.

Differential Revision: https://reviews.llvm.org/D76082
2020-03-13 19:28:45 +00:00
Richard Sandiford b50d80c1ee [Sema][SVE] Don't allow fields to have sizeless type
The SVE ACLE doesn't allow fields to have sizeless type.  At the moment
clang accepts things like:

  struct s { __SVInt8_t x; } y;

but trying to code-generate it leads to LLVM asserts like:

  llvm/include/llvm/Support/TypeSize.h:126: uint64_t llvm::TypeSize::getFixedSize() const: Assertion `!IsScalable && "Request for a fixed size on a scalable object"' failed.

This patch adds an associated clang diagnostic.

Differential Revision: https://reviews.llvm.org/D75737
2020-03-13 19:22:23 +00:00
Nick Desaulniers 246398ece7 [clang][Parse] properly parse asm-qualifiers, asm inline
Summary:
The parsing of GNU C extended asm statements was a little brittle and
had a few issues:
- It was using Parse::ParseTypeQualifierListOpt to parse the `volatile`
  qualifier.  That parser is really meant for TypeQualifiers; an asm
  statement doesn't really have a type qualifier. This is still maybe
  nice to have, but not necessary. We now can check for the `volatile`
  token by properly expanding the grammer, rather than abusing
  Parse::ParseTypeQualifierListOpt.
- The parsing of `goto` was position dependent, so `asm goto volatile`
  wouldn't parse. The qualifiers should be position independent to one
  another. Now they are.
- We would warn on duplicate `volatile`, but the parse error for
  duplicate `goto` was a generic parse error and wasn't clear.
- We need to add support for the recent GNU C extension `asm inline`.
  Adding support to the parser with the above issues highlighted the
  need for this refactoring.

Link: https://gcc.gnu.org/onlinedocs/gcc/Extended-Asm.html

Reviewers: aaron.ballman

Reviewed By: aaron.ballman

Subscribers: aheejin, jfb, nathanchance, cfe-commits, echristo, efriedma, rsmith, chandlerc, craig.topper, erichkeane, jyu2, void, srhines

Tags: #clang

Differential Revision: https://reviews.llvm.org/D75563
2020-03-12 15:13:59 -07:00
Richard Sandiford f8700db7f1 [Sema][SVE] Don't allow static or thread-local variables to have sizeless type
clang accepts a TU containing just:

  __SVInt8_t x;

However, sizeless types are not allowed to have static or thread-local
storage duration and trying to code-generate the TU triggers an LLVM
fatal error:

  Globals cannot contain scalable vectors
  <vscale x 16 x i8>* @x
  fatal error: error in backend: Broken module found, compilation aborted!

This patch adds an associated clang diagnostic.

Differential Revision: https://reviews.llvm.org/D75736
2020-03-12 17:39:29 +00:00
Richard Sandiford adb290d974 [Sema][SVE] Reject atomic sizeless types
It would be difficult to guarantee atomicity for sizeless types,
so the SVE ACLE makes atomic sizeless types invalid.  As it happens,
we already rejected them before the patch, but for the wrong reason:

  error: _Atomic cannot be applied to type 'svint8_t' (aka '__SVInt8_t')
  which is not trivially copyable

The SVE types should be treated as trivially copyable; a later
patch fixes that.

Differential Revision: https://reviews.llvm.org/D75734
2020-03-12 17:20:23 +00:00
Richard Sandiford 627b5c1206 [Sema][SVE] Reject aligned/_Alignas for sizeless types
A previous patch rejected alignof for sizeless types.  This patch
extends that to cover the "aligned" attribute and _Alignas.  Since
sizeless types are not meant to be used for long-term data, cannot
be used in aggregates, and cannot have static storage duration,
there shouldn't be any need to fiddle with their alignment.

Like with alignof, this is a conservative position that can be
relaxed in future if it turns out to be too restrictive.

Differential Revision: https://reviews.llvm.org/D75573
2020-03-12 17:12:40 +00:00
Richard Sandiford 39969c7d3a [Sema][SVE] Reject sizeof and alignof for sizeless types
clang current accepts:

  void foo1(__SVInt8_t *x, __SVInt8_t *y) { *x = *y; }
  void foo2(__SVInt8_t *x, __SVInt8_t *y) {
    memcpy(y, x, sizeof(__SVInt8_t));
  }

The first function is valid ACLE code and generates correct LLVM IR.
However, the second function is invalid ACLE code and generates a
zero-length memcpy.  The point of this patch is to reject the use
of sizeof in the second case instead.

There's no similar wrong-code bug for alignof.  However, the SVE ACLE
conservatively treats alignof in the same way as sizeof, just as the
C++ standard does for incomplete types.  The idea is that layout of
sizeless types is an implementation property and isn't defined at
the language level.

Implementation-wise, the patch adds a new CompleteTypeKind enum
that controls whether RequireCompleteType & friends accept sizeless
built-in types.  For now the default is to maintain the status quo
and accept sizeless types.  However, the end of the series will flip
the default and remove the Default enum value.

The patch also adds new ...CompleteSized... wrappers that callers can
use if they explicitly want to reject sizeless types.  The callers then
use diagnostics that have an extra 0/1 parameter to indicats whether
the type is sizeless or not.

The idea is to have three cases:

1. calls that explicitly reject sizeless types, with a tweaked diagnostic
   for the sizeless case

2. calls that explicitly allow sizeless types

3. normal/old-style calls that don't make an explicit choice either way

Once the default is flipped, the 3. calls will conservatively reject
sizeless types, using the same diagnostic as for other incomplete types.

Differential Revision: https://reviews.llvm.org/D75572
2020-03-12 17:06:53 +00:00
Richard Sandiford f09c7d642a [Sema][SVE] Add tests for valid and invalid type usage
This patch adds C and C++ tests for various uses of SVE types.
The tests cover valid uses that are already (correctly) accepted and
invalid uses that are already (correctly) rejected.  Later patches
will expand the tests as they fix other cases.[*]

Some of the tests for invalid uses aren't obviously related to
scalable vectors.  Part of the reason for having them is to make
sure that the quality of the error message doesn't regress once/if
the types are treated as incomplete types.

[*] These later patches all fix invalid uses that are being incorrectly
    accepted.  I don't know of any cases in which valid uses are being
    incorrectly rejected.  In other words, this series is all about
    diagnosing invalid code rather than enabling something new.

Differential Revision: https://reviews.llvm.org/D75571
2020-03-12 16:56:13 +00:00
Mikhail Maltsev 47edf5bafb [ARM,CDE] Generalize MVE intrinsics infrastructure to support CDE
Summary:
This patch generalizes the existing code to support CDE intrinsics
which will share some properties with existing MVE intrinsics
(some of the intrinsics will be polymorphic and accept/return values
of MVE vector types).
Specifically the patch:
* Adds new tablegen backends -gen-arm-cde-builtin-def,
  -gen-arm-cde-builtin-codegen, -gen-arm-cde-builtin-sema,
  -gen-arm-cde-builtin-aliases, -gen-arm-cde-builtin-header based on
  existing MVE backends.
* Renames the '__clang_arm_mve_alias' attribute into
  '__clang_arm_builtin_alias' (it will be used with CDE intrinsics as
  well as MVE intrinsics)
* Implements semantic checks for the coprocessor argument of the CDE
  intrinsics as well as the existing coprocessor intrinsics.
* Adds one CDE intrinsic __arm_cx1 to test the above changes

Reviewers: simon_tatham, MarkMurrayARM, ostannard, dmgreen

Reviewed By: simon_tatham

Subscribers: sdesmalen, mgorny, kristof.beyls, danielkiss, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D75850
2020-03-10 14:03:16 +00:00
Arthur Eubanks 51d7f64544 Don't emit pointer to int cast warnings under -Wmicrosoft-cast
Summary:
MSVC also warns on this:
$ cat /tmp/a.c
int f(void* p) { return (int) p; }

$ cl /c /tmp/a.c
C:/src/tmp/a.c(1): warning C4311: 'type cast': pointer truncation from
'void *' to 'int'

Warnings originally added in https://reviews.llvm.org/D72231.

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D75643
2020-03-09 13:27:46 -07:00
Erich Keane cc8390bfe3 Permit attribute 'used' with 'target' multiversioning.
This adds infrastructure for a multiversioning whitelist, plus adds
'used' to the allowed list with 'target'.  The behavior here mirrors the
implementation in GCC, where 'used' only applies to the single
declaration and doesn't apply to the ifunc or resolver.

This is not being applied to cpu_dispatch and cpu_specific, since the
rules are more complicated for cpu_specific, which emits multiple
symbols. Additionally, the author isn't currently aware of uses in the
wild of this combination, but is aware of a number of target+used
combinations.
2020-03-09 12:38:03 -07:00
Jeremy Stenglein 90e791d732 Add test missed in r843a9778fcd5
Differential Revision: https://reviews.llvm.org/D75768
2020-03-09 10:54:56 -07:00
Nathan Chancellor 2a41b31fcd [Sema] Add -Wpointer-to-enum-cast and -Wvoid-pointer-to-enum-cast
GCC does not warn on casts from pointers to enumerators, while clang
currently does: https://godbolt.org/z/3DFDVG

This causes a bunch of extra warnings in the Linux kernel, where
certain structs contain a void pointer to avoid using a gigantic
union for all of the various types of driver data, such as
versions.

Add a diagnostic that allows certain projects like the kernel to
disable the warning just for enums, which allows those projects to
keep full compatibility with GCC but keeps the intention of treating
casts to integers and enumerators the same by default so that other
projects have the opportunity to catch issues not noticed before (or
follow suite and disable the warning).

Link: https://github.com/ClangBuiltLinux/linux/issues/887

Reviewed By: rjmccall

Differential Revision: https://reviews.llvm.org/D75758
2020-03-07 16:43:39 -08:00
Aaron Puchert f23df1b2a3 Comment parsing: Treat \ref as inline command
Summary:
It's basically Doxygen's version of a link and can happen anywhere
inside of a paragraph. Fixes a bogus warning about empty paragraphs when
a parameter description starts with a link.

Reviewers: gribozavr2

Reviewed By: gribozavr2

Differential Revision: https://reviews.llvm.org/D75632
2020-03-05 19:44:34 +01:00
Erik Pilkington 29a4239d31 [Sema] Fix a crash when attaching comments to an implicit decl
When an implicitly generated decl was the first entry in the group, we
attempted to lookup comments with an empty FileID, leading to crashes. Avoid
this by trying to use the other declarations in the group, and then bailing out
if none are valid.

rdar://59919733
Differential revision: https://reviews.llvm.org/D75483
2020-03-02 16:49:53 -08:00
Luboš Luňák c61401b897 Revert "[clang] detect switch fallthrough marked by a comment (PR43465)"
This reverts commit 398b4ed87d.
As requested in https://bugs.llvm.org/show_bug.cgi?id=43465#c37 .
2020-03-02 22:33:25 +01:00
zoecarver 6201f6601d Check args passed to __builtin_frame_address and __builtin_return_address.
Verifies that an argument passed to __builtin_frame_address or __builtin_return_address is within the range [0, 0xFFFF]

Differential revision: https://reviews.llvm.org/D66839

Re-committed after fixed: c93112dc4f
2020-02-25 12:47:14 -08:00
Anastasia Stulova fa755d3e71 [Sema][C++] Propagate conversion kind to specialize the diagnostics
Compute and propagate conversion kind to diagnostics helper in C++
to provide more specific diagnostics about incorrect implicit
conversions in assignments, initializations, params, etc...

Duplicated some diagnostics as errors because C++ is more strict.

Tags: #clang

Differential Revision: https://reviews.llvm.org/D74116
2020-02-25 16:05:37 +00:00
Bill Wendling 50cac24877 Support output constraints on "asm goto"
Summary:
Clang's "asm goto" feature didn't initially support outputs constraints. That
was the same behavior as gcc's implementation. The decision by gcc not to
support outputs was based on a restriction in their IR regarding terminators.
LLVM doesn't restrict terminators from returning values (e.g. 'invoke'), so
it made sense to support this feature.

Output values are valid only on the 'fallthrough' path. If an output value's used
on an indirect branch, then it's 'poisoned'.

In theory, outputs *could* be valid on the 'indirect' paths, but it's very
difficult to guarantee that the original semantics would be retained. E.g.
because indirect labels could be used as data, we wouldn't be able to split
critical edges in situations where two 'callbr' instructions have the same
indirect label, because the indirect branch's destination would no longer be
the same.

Reviewers: jyknight, nickdesaulniers, hfinkel

Reviewed By: jyknight, nickdesaulniers

Subscribers: MaskRay, rsmith, hiraditya, llvm-commits, cfe-commits, craig.topper, rnk

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D69876
2020-02-24 18:51:29 -08:00
zoecarver 6980782572 Revert "Validate argument passed to __builtin_frame_address and __builtin_return_address"
This reverts commit c93112dc4f.
2020-02-24 14:35:02 -08:00
zoecarver c93112dc4f Validate argument passed to __builtin_frame_address and __builtin_return_address
Verifies that the argument passed to __builtin_frame_address and __builtin_return_address is within the range [0, 0xFFFF].
2020-02-24 14:23:41 -08:00
Mark de Wever 56eb15a1c7 [Sema] Fix pointer-to-int-cast diagnostic for _Bool
The diagnostic added in D72231 also shows a diagnostic when casting to a
_Bool. This is unwanted. This patch removes the diagnostic for _Bool types.

Differential Revision: https://reviews.llvm.org/D74860
2020-02-22 19:39:49 +01:00
Jan Korous 2f56789c8f [clang][doxygen] Fix false -Wdocumentation warning for tag typedefs
For tag typedefs like this one:

/*!
@class Foo
*/
typedef class { } Foo;

clang -Wdocumentation gives:

warning: '@class' command should not be used in a comment attached to a
non-struct declaration [-Wdocumentation]

... while doxygen seems fine with it.

Differential Revision: https://reviews.llvm.org/D74746
2020-02-20 11:32:30 -08:00
Roman Lebedev 9ea5d17cc9
[Sema] Demote call-site-based 'alignment is a power of two' check for AllocAlignAttr into a warning
Summary:
As @rsmith notes in https://reviews.llvm.org/D73020#inline-672219
while that is certainly UB land, it may not be actually reachable at runtime, e.g.:
```
template<int N> void *make() {
  if ((N & (N-1)) == 0)
    return operator new(N, std::align_val_t(N));
  else
    return operator new(N);
}
void *p = make<7>();
```
and we shouldn't really error-out there.

That being said, i'm not really following the logic here.
Which ones of these cases should remain being an error?

Reviewers: rsmith, erichkeane

Reviewed By: erichkeane

Subscribers: cfe-commits, rsmith

Tags: #clang

Differential Revision: https://reviews.llvm.org/D73996
2020-02-20 16:39:26 +03:00
John Marshall 260b91f379 Use getLocation() in "too few/too many arguments" diagnostic
Use the more accurate location when emitting the location of the
function being called's prototype in diagnostics emitted when calling
a function with an incorrect number of arguments.

In particular, avoids showing a trace of irrelevant macro expansions
for "MY_EXPORT static int AwesomeFunction(int, int);". Fixes PR#23564.
2020-02-18 11:23:17 -05:00
Mark de Wever af20211944 [Sema] Fix pointer-to-int-cast for MSVC build bot
Revision 9658d895c8 breaks the clang-x64-windows-msvc build bot [1].
This should fix the unit test using the same method as used in 9658d895c8.

Note I don't have access to a Windows system so the patch is based on the
errors generated by the bot.

[1] http://lab.llvm.org:8011/builders/clang-x64-windows-msvc/builds/14358

Differential Revision: https://reviews.llvm.org/D74694
2020-02-16 19:09:59 +01:00
Mark de Wever 9658d895c8 [Sema] Adds the pointer-to-int-cast diagnostic
Converting a pointer to an integer whose result cannot represented in the
integer type is undefined behavior is C and prohibited in C++. C++ already
has a diagnostic when casting. This adds a diagnostic for C.

Since this diagnostic uses the range of the conversion it also modifies
int-to-pointer-cast diagnostic to use a range.

Fixes PR8718: No warning on casting between pointer and non-pointer-sized int

Differential Revision: https://reviews.llvm.org/D72231
2020-02-16 15:38:25 +01:00
Aaron Puchert 705306526b Fix tests after previous commit
We don't want to test for this warning, so we just fix it.
2020-02-14 19:41:01 +01:00
Aaron Puchert 2f26bc5542 Warn about zero-parameter K&R definitions in -Wstrict-prototypes
Summary:
Zero-parameter K&R definitions specify that the function has no
parameters, but they are still not prototypes, so calling the function
with the wrong number of parameters is just a warning, not an error.

The C11 standard doesn't seem to directly define what a prototype is,
but it can be inferred from 6.9.1p7: "If the declarator includes a
parameter type list, the list also specifies the types of all the
parameters; such a declarator also serves as a function prototype
for later calls to the same function in the same translation unit."
This refers to 6.7.6.3p5: "If, in the declaration “T D1”, D1 has
the form
    D(parameter-type-list)
or
    D(identifier-list_opt)
[...]". Later in 6.11.7 it also refers only to the parameter-type-list
variant as prototype: "The use of function definitions with separate
parameter identifier and declaration lists (not prototype-format
parameter type and identifier declarators) is an obsolescent feature."

We already correctly treat an empty parameter list as non-prototype
declaration, so we can just take that information.

GCC also warns about this with -Wstrict-prototypes.

This shouldn't affect C++, because there all FunctionType's are
FunctionProtoTypes. I added a simple test for that.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D66919
2020-02-14 19:25:02 +01:00
Guillaume Chatelet d65bbf81f8 [clang] Add support for __builtin_memcpy_inline
Summary: This is a follow up on D61634 and the last step to implement http://lists.llvm.org/pipermail/llvm-dev/2019-April/131973.html

Reviewers: efriedma, courbet, tejohnson

Subscribers: hiraditya, cfe-commits, llvm-commits, jdoerfert, t.p.northover

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D73543
2020-02-07 23:55:26 +01:00
Douglas Yung 02fffbb5fa Fix test after test changes added in da3dc00 caused the test to break
on platforms that default to an older C standard (like the PS4).

This should fix the test failure on the PS4 bots.
2020-02-06 18:19:01 -08:00
Richard Smith da3dc0011e PR44684: Look through parens and similar constructs when determining
whether a call is to a builtin.

We already had a general mechanism to do this but for some reason
weren't using it. In passing, check for the other unary operators that
can intervene in a reasonably-direct function call (we already handled
'&' but missed '*' and '+').

This reverts commit aaae6b1b61,
reinstating af80b8ccc5, with a fix to
clang-tidy.
2020-02-06 12:21:54 -08:00
Mikhail Maltsev 2694cc3dca [ARM][MVE] Add fixed point vector conversion intrinsics
Summary:
This patch implements the following Arm ACLE MVE intrinsics:
* vcvtq_n_*
* vcvtq_m_n_*
* vcvtq_x_n_*

and two corresponding LLVM IR intrinsics:
* int_arm_mve_vcvt_fix (vcvtq_n_*)
* int_arm_mve_vcvt_fix_predicated (vcvtq_m_n_*, vcvtq_x_n_*)

Reviewers: simon_tatham, ostannard, MarkMurrayARM, dmgreen

Reviewed By: MarkMurrayARM

Subscribers: kristof.beyls, hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D74134
2020-02-06 16:49:45 +00:00
Luboš Luňák 398b4ed87d [clang] detect switch fallthrough marked by a comment (PR43465)
The regex can be extended if needed, but this should probably handle
most of the cases.

Differential Revision: https://reviews.llvm.org/D73852
2020-02-03 19:33:05 +01:00
Simon Tatham f8d4afc49a [ARM,MVE] Add intrinsics for v[id]dupq and v[id]wdupq.
Summary:
These instructions generate a vector of consecutive elements starting
from a given base value and incrementing by 1, 2, 4 or 8. The `wdup`
versions also wrap the values back to zero when they reach a given
limit value. The instruction updates the scalar base register so that
another use of the same instruction will continue the sequence from
where the previous one left off.

At the IR level, I've represented these instructions as a family of
target-specific intrinsics with two return values (the constructed
vector and the updated base). The user-facing ACLE API provides a set
of intrinsics that throw away the written-back base and another set
that receive it as a pointer so they can update it, plus the usual
predicated versions.

Because the intrinsics return two values (as do the underlying
instructions), the isel has to be done in C++.

This is the first family of MVE intrinsics that use the `imm_1248`
immediate type in the clang Tablegen framework, so naturally, I found
I'd given it the wrong C integer type. Also added some tests of the
check that the immediate has a legal value, because this is the first
time those particular checks have been exercised.

Finally, I also had to fix a bug in MveEmitter which failed an
assertion when I nested two `seq` nodes (the inner one used to extract
the two values from the pair returned by the IR intrinsic, and the
outer one put on by the predication multiclass).

Reviewers: dmgreen, MarkMurrayARM, miyuki, ostannard

Reviewed By: dmgreen

Subscribers: kristof.beyls, hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D73357
2020-02-03 11:20:06 +00:00
Nico Weber e916c8dfe4 Revert "[Clang] Warn about 'z' printf modifier in old MSVC."
This reverts commit fe0d1b6a8a.
Makes Analysis/taint-generic.c fail on some Windows systems.
2020-01-28 09:27:54 -05:00
Nico Weber aaae6b1b61 Revert "PR44684: Look through parens and similar constructs when determining"
This reverts commit af80b8ccc5.
It broke clang-tidy/checkers/modernize-use-uncaught-exceptions.cpp in
check-clang-tools on macOS and Windows, see e.g.
http://lab.llvm.org:8011/builders/clang-x64-windows-msvc/builds/13976/steps/stage%201%20check/logs/stdio
2020-01-28 09:03:27 -05:00
Simon Tatham fe0d1b6a8a [Clang] Warn about 'z' printf modifier in old MSVC.
Summary:
The 'z' length modifier, signalling that an integer format specifier
takes a `size_t` sized integer, is only supported by the C library of
MSVC 2015 and later. Earlier versions don't recognize the 'z' at all,
and respond to `printf("%zu", x)` by just printing "zu".

So, if the MS compatibility version is set to a value earlier than
MSVC2015, it's useful to warn about 'z' modifiers in printf format
strings we check.

Reviewers: aaron.ballman, lebedev.ri, rnk, majnemer, zturner

Reviewed By: aaron.ballman

Subscribers: amccarth, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D73457
2020-01-28 09:04:45 +00:00
Richard Smith af80b8ccc5 PR44684: Look through parens and similar constructs when determining
whether a call is to a builtin.

We already had a general mechanism to do this but for some reason
weren't using it. In passing, check for the other unary operators that
can intervene in a reasonably-direct function call (we already handled
'&' but missed '*' and '+').
2020-01-27 18:20:57 -08:00
serge-sans-paille 6d485ff455 Improve static checks for sprintf and __builtin___sprintf_chk
Implement a pessimistic evaluator of the minimal required size for a buffer
based on the format string, and couple that with the fortified version to emit a
warning when the buffer size is lower than the lower bound computed from the
format string.

Differential Revision: https://reviews.llvm.org/D71566
2020-01-25 18:10:34 +01:00
Roman Lebedev 1d0972ff5e
[Sema] Introduce MaximumAlignment value, to be used instead of magical constants
There is llvm::Value::MaximumAlignment, which is numerically
equivalent to these constants, but we can't use it directly
because we can't include llvm IR headers in clang Sema.
So instead, copy-paste the constant, and fixup the places to use it.

This was initially reviewed in https://reviews.llvm.org/D72998
2020-01-24 17:49:17 +03:00
Roman Lebedev 0a002f679b
[Sema] Try 2: Sanity-check alignment requested via `__attribute__((assume_aligned(imm)))`
Summary:
For `__builtin_assume_aligned()`, we do validate that the alignment
is not greater than `536870912` (D68824), but we don't do that for
`__attribute__((assume_aligned(N)))` attribute.
I suspect we should.

This was initially committed in a4cfb15d15
but reverted in 210f0882c9 due to
suspicious bot failures.

Reviewers: erichkeane, aaron.ballman, hfinkel, rsmith, jdoerfert

Reviewed By: erichkeane

Subscribers: cfe-commits, llvm-commits

Tags: #llvm, #clang

Differential Revision: https://reviews.llvm.org/D72994
2020-01-24 16:56:39 +03:00
Roman Lebedev ba545c814b
[Sema] Try 2: Attempt to perform call-size-specific `__attribute__((alloc_align(param_idx)))` validation
Summary:
`alloc_align` attribute takes parameter number, not the alignment itself,
so given **just** the attribute/function declaration we can't do any
sanity checking for said alignment.

However, at call site, given the actual `Expr` that is passed
into that parameter, we //might// be able to evaluate said `Expr`
as Integer Constant Expression, and perform the sanity checks.
But since there is no requirement for that argument to be an immediate,
we may fail, and that's okay.

However if we did evaluate, we should enforce the same constraints
as with `__builtin_assume_aligned()`/`__attribute__((assume_aligned(imm)))`:
said alignment is a power of two, and is not greater than our magic threshold


This was initially committed in c2a9061ac5
but reverted in 00756b1823 because of
suspicious bot failures.

Reviewers: erichkeane, aaron.ballman, hfinkel, rsmith, jdoerfert

Reviewed By: erichkeane

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D72996
2020-01-24 14:42:45 +03:00
Fangrui Song 69bf40c45f [Driver][CodeGen] Support -fpatchable-function-entry=N,M and __attribute__((patchable_function_entry(N,M))) where M>0
Reviewed By: nickdesaulniers

Differential Revision: https://reviews.llvm.org/D73072
2020-01-23 17:02:54 -08:00
Roman Lebedev 210f0882c9
Revert "[Sema] Sanity-check alignment requested via `__attribute__((assume_aligned(imm)))`"
Likely makes bots angry.

This reverts commit a4cfb15d15.

# Conflicts:
#	clang/lib/Sema/SemaDeclAttr.cpp
2020-01-23 23:10:35 +03:00
Roman Lebedev 00756b1823
Revert "[Sema] Attempt to perform call-size-specific `__attribute__((alloc_align(param_idx)))` validation"
Likely makes bots angry.

This reverts commit c2a9061ac5.
2020-01-23 23:10:34 +03:00
Roman Lebedev c2a9061ac5
[Sema] Attempt to perform call-size-specific `__attribute__((alloc_align(param_idx)))` validation
Summary:
`alloc_align` attribute takes parameter number, not the alignment itself,
so given **just** the attribute/function declaration we can't do any
sanity checking for said alignment.

However, at call site, given the actual `Expr` that is passed
into that parameter, we //might// be able to evaluate said `Expr`
as Integer Constant Expression, and perform the sanity checks.
But since there is no requirement for that argument to be an immediate,
we may fail, and that's okay.

However if we did evaluate, we should enforce the same constraints
as with `__builtin_assume_aligned()`/`__attribute__((assume_aligned(imm)))`:
said alignment is a power of two, and is not greater than our magic threshold

Reviewers: erichkeane, aaron.ballman, hfinkel, rsmith, jdoerfert

Reviewed By: erichkeane

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D72996
2020-01-23 22:50:49 +03:00
Roman Lebedev a4cfb15d15
[Sema] Sanity-check alignment requested via `__attribute__((assume_aligned(imm)))`
Summary:
For `__builtin_assume_aligned()`, we do validate that the alignment
is not greater than `536870912` (D68824), but we don't do that for
`__attribute__((assume_aligned(N)))` attribute.
I suspect we should.

Reviewers: erichkeane, aaron.ballman, hfinkel, rsmith, jdoerfert

Reviewed By: erichkeane

Subscribers: cfe-commits, llvm-commits

Tags: #llvm, #clang

Differential Revision: https://reviews.llvm.org/D72994
2020-01-23 22:50:48 +03:00
Simon Tatham 4321c6af28 [ARM,MVE] Support immediate vbicq,vorrq,vmvnq intrinsics.
Summary:
Immediate vmvnq is code-generated as a simple vector constant in IR,
and left to the backend to recognize that it can be created with an
MVE VMVN instruction. The predicated version is represented as a
select between the input and the same constant, and I've added a
Tablegen isel rule to turn that into a predicated VMVN. (That should
be better than the previous VMVN + VPSEL: it's the same number of
instructions but now it can fold into an adjacent VPT block.)

The unpredicated forms of VBIC and VORR are done by enabling the same
isel lowering as for NEON, recognizing appropriate immediates and
rewriting them as ARMISD::VBICIMM / ARMISD::VORRIMM SDNodes, which I
then instruction-select into the right MVE instructions (now that I've
also reworked those instructions to use the same MC operand encoding).
In order to do that, I had to promote the Tablegen SDNode instance
`NEONvorrImm` to a general `ARMvorrImm` available in MVE as well, and
similarly for `NEONvbicImm`.

The predicated forms of VBIC and VORR are represented as a vector
select between the original input vector and the output of the
unpredicated operation. The main convenience of this is that it still
lets me use the existing isel lowering for VBICIMM/VORRIMM, and not
have to write another copy of the operand encoding translation code.

This intrinsic family is the first to use the `imm_simd` system I put
into the MveEmitter tablegen backend. So, naturally, it showed up a
bug or two (emitting bogus range checks and the like). Fixed those,
and added a full set of tests for the permissible immediates in the
existing Sema test.

Also adjusted the isel pattern for `vmovlb.u8`, which stopped matching
because lowering started turning its input into a VBICIMM. Now it
recognizes the VBICIMM instead.

Reviewers: dmgreen, MarkMurrayARM, miyuki, ostannard

Reviewed By: dmgreen

Subscribers: kristof.beyls, hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D72934
2020-01-23 11:53:52 +00:00
Aaron Ballman a8c2f76cd2 Removing an accidentally duplicated line of test code to fix bots. 2020-01-21 16:03:22 -05:00
Etienne Pierre-Doray 5260bc2497 Allow arbitrary capability name in Thread Safety Analysis
Restricting the names of capabilities to only "role" or "mutex" makes
for awkward diagnostic text, such as with:
https://chromium-review.googlesource.com/c/chromium/src/+/1948098/19/base/sequence_checker_unittest.nc#33
2020-01-21 15:43:17 -05:00
Mitch Phillips edd4398f4c Revert "PR17164: Change clang's default behavior from -flax-vector-conversions=all to -flax-vector-conversions=integer."
This patch broke the Sanitizer buildbots. Please see the commit's
differential revision for more information
(https://reviews.llvm.org/D67678).

This reverts commit b72a8c65e4.
2020-01-20 16:34:09 -08:00
Krzysztof Parzyszek 6f3effbbf0 [Hexagon] Update autogenerated intrinsic info in clang
In addition to that, use target features to validate intrinsic
availability on a given target.
2020-01-16 14:20:12 -06:00
Richard Smith b72a8c65e4 PR17164: Change clang's default behavior from -flax-vector-conversions=all to -flax-vector-conversions=integer.
Summary:
See proposal on cfe-dev:
http://lists.llvm.org/pipermail/cfe-dev/2019-April/062030.html

Reviewers: SjoerdMeijer, eli.friedman

Subscribers: kristof.beyls, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D67678
2020-01-15 13:14:57 -08:00
Simon Tatham ada01d1b86 [clang] New __attribute__((__clang_arm_mve_strict_polymorphism)).
This is applied to the vector types defined in <arm_mve.h> for use
with the intrinsics for the ARM MVE vector architecture.

Its purpose is to inhibit lax vector conversions, but only in the
context of overload resolution of the MVE polymorphic intrinsic
functions. This solves an ambiguity problem with polymorphic MVE
intrinsics that take a vector and a scalar argument: the scalar
argument can often have the wrong integer type due to default integer
promotions or unsuffixed literals, and therefore, the type of the
vector argument should be considered trustworthy when resolving MVE
polymorphism.

As part of the same change, I've added the new attribute to the
declarations generated by the MveEmitter Tablegen backend (and
corrected a namespace issue with the other attribute while I was
there).

Reviewers: aaron.ballman, dmgreen

Reviewed By: aaron.ballman

Subscribers: kristof.beyls, JDevlieghere, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D72518
2020-01-15 15:04:10 +00:00
Erich Keane 349636d2bf Implement VectorType conditional operator GNU extension.
GCC supports the conditional operator on VectorTypes that acts as a
'select' in C++ mode. This patch implements the support. Types are
converted as closely to GCC's behavior as possible, though in a few
places consistency with our existing vector type support was preferred.

Note that this implementation is different from the OpenCL version in a
number of ways, so it unfortunately required a different implementation.

First, the SEMA rules and promotion rules are significantly different.

Secondly, GCC implements COND[i] != 0 ? LHS[i] : RHS[i] (where i is in
the range 0- VectorSize, for each element).  In OpenCL, the condition is
COND[i] < 0 ? LHS[i]: RHS[i].

In the process of implementing this, it was also required to make the
expression COND ? LHS : RHS type dependent if COND is type dependent,
since the type is now dependent on the condition.  For example:

    T ? 1 : 2;

Is not typically type dependent, since the result can be deduced from
the operands.  HOWEVER, if T is a VectorType now, it could change this
to a 'select' (basically a swizzle with a non-constant mask) with the 1
and 2 being promoted to vectors themselves.

While this is a change, it is NOT a standards incompatible change. Based
on my (and D. Gregor's, at the time of writing the code) reading of the
standard, the expression is supposed to be type dependent if ANY
sub-expression is type dependent.

Differential Revision: https://reviews.llvm.org/D71463
2020-01-13 13:27:20 -08:00
Fangrui Song a44c434b68 Support function attribute patchable_function_entry
This feature is generic. Make it applicable for AArch64 and X86 because
the backend has only implemented NOP insertion for AArch64 and X86.

Reviewed By: nickdesaulniers, aaron.ballman

Differential Revision: https://reviews.llvm.org/D72221
2020-01-10 09:57:34 -08:00
Andrew Paverd bdd88b7ed3 Add support for __declspec(guard(nocf))
Summary:
Avoid using the `nocf_check` attribute with Control Flow Guard. Instead, use a
new `"guard_nocf"` function attribute to indicate that checks should not be
added on indirect calls within that function. Add support for
`__declspec(guard(nocf))` following the same syntax as MSVC.

Reviewers: rnk, dmajor, pcc, hans, aaron.ballman

Reviewed By: aaron.ballman

Subscribers: aaron.ballman, tomrittervg, hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D72167
2020-01-10 16:04:12 +00:00
Alex Richardson 8c387cbea7 Add builtins for aligning and checking alignment of pointers and integers
This change introduces three new builtins (which work on both pointers
and integers) that can be used instead of common bitwise arithmetic:
__builtin_align_up(x, alignment), __builtin_align_down(x, alignment) and
__builtin_is_aligned(x, alignment).

I originally added these builtins to the CHERI fork of LLVM a few years ago
to handle the slightly different C semantics that we use for CHERI [1].
Until recently these builtins (or sequences of other builtins) were
required to generate correct code. I have since made changes to the default
C semantics so that they are no longer strictly necessary (but using them
does generate slightly more efficient code). However, based on our experience
using them in various projects over the past few years, I believe that adding
these builtins to clang would be useful.

These builtins have the following benefit over bit-manipulation and casts
via uintptr_t:

- The named builtins clearly convey the semantics of the operation. While
  checking alignment using __builtin_is_aligned(x, 16) versus
  ((x & 15) == 0) is probably not a huge win in readably, I personally find
  __builtin_align_up(x, N) a lot easier to read than (x+(N-1))&~(N-1).
- They preserve the type of the argument (including const qualifiers). When
  using casts via uintptr_t, it is easy to cast to the wrong type or strip
  qualifiers such as const.
- If the alignment argument is a constant value, clang can check that it is
  a power-of-two and within the range of the type. Since the semantics of
  these builtins is well defined compared to arbitrary bit-manipulation,
  it is possible to add a UBSAN checker that the run-time value is a valid
  power-of-two. I intend to add this as a follow-up to this change.
- The builtins avoids int-to-pointer casts both in C and LLVM IR.
  In the future (i.e. once most optimizations handle it), we could use the new
  llvm.ptrmask intrinsic to avoid the ptrtoint instruction that would normally
  be generated.
- They can be used to round up/down to the next aligned value for both
  integers and pointers without requiring two separate macros.
- In many projects the alignment operations are already wrapped in macros (e.g.
  roundup2 and rounddown2 in FreeBSD), so by replacing the macro implementation
  with a builtin call, we get improved diagnostics for many call-sites while
  only having to change a few lines.
- Finally, the builtins also emit assume_aligned metadata when used on pointers.
  This can improve code generation compared to the uintptr_t casts.

[1] In our CHERI compiler we have compilation mode where all pointers are
implemented as capabilities (essentially unforgeable 128-bit fat pointers).
In our original model, casts from uintptr_t (which is a 128-bit capability)
to an integer value returned the "offset" of the capability (i.e. the
difference between the virtual address and the base of the allocation).
This causes problems for cases such as checking the alignment: for example, the
expression `if ((uintptr_t)ptr & 63) == 0` is generally used to check if the
pointer is aligned to a multiple of 64 bytes. The problem with offsets is that
any pointer to the beginning of an allocation will have an offset of zero, so
this check always succeeds in that case (even if the address is not correctly
aligned). The same issues also exist when aligning up or down. Using the
alignment builtins ensures that the address is used instead of the offset. While
I have since changed the default C semantics to return the address instead of
the offset when casting, this offset compilation mode can still be used by
passing a command-line flag.

Reviewers: rsmith, aaron.ballman, theraven, fhahn, lebedev.ri, nlopes, aqjune
Reviewed By: aaron.ballman, lebedev.ri
Differential Revision: https://reviews.llvm.org/D71499
2020-01-09 21:48:29 +00:00
Simon Tatham d857e114b5 [ARM,MVE] Fix valid immediate range for vsliq_n.
In common with most MVE immediate shift instructions, the left shift
takes an immediate in the range [0,n-1], while the right shift takes
one in the range [1,n]. I had absent-mindedly made them both the
latter.

While I'm here, I've added a set of regression tests checking both
ends of the immediate range for a representative sample of the
immediate shifts.
2020-01-09 15:04:47 +00:00
Simon Tatham 4978296cd8 [ARM,MVE] Support -ve offsets in gather-load intrinsics.
Summary:
The ACLE intrinsics with `gather_base` or `scatter_base` in the name
are wrappers on the MVE load/store instructions that take a vector of
base addresses and an immediate offset. The immediate offset can be up
to 127 times the alignment unit, and it can be positive or negative.

At the MC layer, we got that right. But in the Sema error checking for
the wrapping intrinsics, the offset was erroneously constrained to be
positive.

To fix this I've adjusted the `imm_mem7bit` class in the Tablegen that
defines the intrinsics. But that causes integer literals like
`0xfffffffffffffe04` to appear in the autogenerated calls to
`SemaBuiltinConstantArgRange`, which provokes a compiler warning
because that's out of the non-overflowing range of an `int64_t`. So
I've also tweaked `MveEmitter` to emit that as `-0x1fc` instead.

Updated the tests of the Sema checks themselves, and also adjusted a
random sample of the CodeGen tests to actually use negative offsets
and prove they get all the way through code generation without causing
a crash.

Reviewers: dmgreen, miyuki, MarkMurrayARM

Reviewed By: dmgreen

Subscribers: kristof.beyls, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D72268
2020-01-06 16:33:07 +00:00
Bruno Ricci 8a571538df
[Sema] SequenceChecker: Fix handling of operator ||, && and ?:
The current handling of the operators ||, && and ?: has a number of false
positive and false negative. The issues for operator || and && are:

1. We need to add sequencing regions for the LHS and RHS as is done for the
   comma operator. Not doing so causes false positives in expressions like
   `((a++, false) || (a++, false))` (from PR39779, see PR22197 for another
    example).

2. In the current implementation when the evaluation of the LHS fails, the RHS
   is added to a worklist to be processed later. This results in false negatives
   in expressions like `(a && a++) + a`.

Fix these issues by introducing sequencing regions for the LHS and RHS, and by
not deferring the visitation of the RHS.

The issues with the ternary operator ?: are similar, with the added twist that
we should not warn on expressions like `(x ? y += 1 : y += 2)` since exactly
one of the 2nd and 3rd expression is going to be evaluated, but we should still
warn on expressions like `(x ? y += 1 : y += 2) = y`.

Differential Revision: https://reviews.llvm.org/D57747

Reviewed By: rsmith
2019-12-22 12:27:31 +00:00
Mark de Wever be1a9b3863 [Wdocumentation] Implement \anchor
Differential revision: https://reviews.llvm.org/D69223
2019-12-21 14:52:21 +01:00
Gabor Horvath fe17b30a79 [attributes][analyzer] Add annotations for handles.
These annotations will be used in an upcomming static analyzer check
that finds handle leaks, use after releases, and double releases.

Differential Revision: https://reviews.llvm.org/D70469
2019-12-20 11:47:55 -08:00
Amy Huang a85f5efd95 Add support for the MS qualifiers __ptr32, __ptr64, __sptr, __uptr.
Summary:
This adds parsing of the qualifiers __ptr32, __ptr64, __sptr, and __uptr and
lowers them to the corresponding address space pointer for 32-bit and 64-bit pointers.
(32/64-bit pointers added in https://reviews.llvm.org/D69639)

A large part of this patch is making these pointers ignore the address space
when doing things like overloading and casting.

https://bugs.llvm.org/show_bug.cgi?id=42359

Reviewers: rnk, rsmith

Subscribers: jholewinski, jvesely, nhaehnle, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D71039
2019-12-18 10:41:12 -08:00
Erich Keane 1ed832e424 Reland [NFC-I] Remove hack for fp-classification builtins
The FP-classification builtins (__builtin_isfinite, etc) use variadic
packs in the definition file to mean an overload set.  Because of that,
floats were converted to doubles, which is incorrect. There WAS a patch
to remove the cast after the fact.

THis patch switches these builtins to just be custom type checking,
calls the implicit conversions for the integer members, and makes sure
the correct L->R casts are put into place, then does type checking like
normal.

A future direction (that wouldn't be NFC) would consider making
conversions for the floating point parameter legal.

Note: The initial patch for this missed that certain systems need to
still convert half to float, since they dont' support that type.
2019-12-17 06:58:29 -08:00
Richard Smith 4b00299958 [c++20] Add deprecation warnings for the expression forms deprecated by P1120R0.
This covers:
 * usual arithmetic conversions (comparisons, arithmetic, conditionals)
   between different enumeration types
 * usual arithmetic conversions between enums and floating-point types
 * comparisons between two operands of array type

The deprecation warnings are on-by-default (in C++20 compilations); it
seems likely that these forms will become ill-formed in C++23, so
warning on them now by default seems wise.

For the first two bullets, off-by-default warnings were also added for
all the cases where we didn't already have warnings (covering language
modes prior to C++20). These warnings are in subgroups of the existing
-Wenum-conversion (except that the first case is not warned on if either
enumeration type is anonymous, consistent with our existing
-Wenum-conversion warnings).
2019-12-16 17:49:45 -08:00
Erich Keane 3f22b4721e Revert "[NFC-I] Remove hack for fp-classification builtins"
This reverts commit b1e542f302.

The original 'hack' didn't chop out fp-16 to double conversions, so
systems that use FP16ConversionIntrinsics end up in IR-CodeGen with an
i16 type isntead of a float type (like PPC64-BE).  The bots noticed
this.

Reverting until I figure out how to fix this
2019-12-16 14:01:51 -08:00
Erich Keane b1e542f302 [NFC-I] Remove hack for fp-classification builtins
The FP-classification builtins (__builtin_isfinite, etc) use variadic
packs in the definition file to mean an overload set.  Because of that,
floats were converted to doubles, which is incorrect. There WAS a patch
to remove the cast after the fact.

THis patch switches these builtins to just be custom type checking,
calls the implicit conversions for the integer members, and makes sure
the correct L->R casts are put into place, then does type checking like
normal.

A future direction (that wouldn't be NFC) would consider making
conversions for the floating point parameter legal.
2019-12-16 12:22:55 -08:00
Mark de Wever b6d386f6f9 [Wdocumentation] Use C2x/C++14 deprecated attribute
This replaces the non-standard __attribute__((deprecated)) with the
standard [[deprecated]] when compiling in C2x/C++14 mode.

Discovered while looking at https://bugs.llvm.org/show_bug.cgi?id=43753

Differential Revision: https://reviews.llvm.org/D71141
2019-12-10 21:16:18 +01:00
Mark de Wever b972f2d05e [Wdocumentation] Properly place deprecated attribute
It is now placed before the function:
- allows to replace __attribute__((deprecated)) with [[deprecated]].
- required for trailing returns.

Fixes bug: https://bugs.llvm.org/show_bug.cgi?id=43753

Differential Revision: https://reviews.llvm.org/D71140
2019-12-10 21:16:12 +01:00
Mark de Wever 85fff898bb [Wdocumentation] Use the command marker.
Use the proper marker for -Wdocumentation-deprecated-sync instead of
hard-coded the backslash.

Discovered while looking at https://bugs.llvm.org/show_bug.cgi?id=43753

Differential Revision: https://reviews.llvm.org/D71139
2019-12-10 21:16:07 +01:00
Carey Williams 76fd58d0fe Revert "[ARM] Allocatable Global Register Variables for ARM"
This reverts commit 2d739f98d8.
2019-11-29 17:01:05 +00:00
Simon Atanasyan f4d32ae75b [mips] Check that features required by built-ins are enabled
Now Clang does not check that features required by built-in functions
are enabled. That causes errors in the backend reported in PR44018.

This patch fixes this bug by checking that required features
are enabled.

This should fix PR44018.

Differential Revision: https://reviews.llvm.org/D70808
2019-11-29 00:23:00 +03:00
Gabor Horvath bcd0798c47 [LifetimeAnalysis] Fix PR44150
References need somewhat special treatment. While copying a gsl::Pointer
will propagate the points-to set, creating an object from a reference
often behaves more like a dereference operation.

Differential Revision: https://reviews.llvm.org/D70755
2019-11-27 09:15:14 -08:00
Yaxun (Sam) Liu ded2490494 Workaround for EvalInfo ctor for MSVC 2017
Current EvalInfo ctor causes EnableNewConstInterp to be true even though
it is supposed to be false on MSVC 2017. This is because a virtual function
getLangOpts() is called in member initializer lists, whereas on MSVC
member ctors are called before function virtual function pointers are
initialized.

This patch fixes that.

Differential Revision: https://reviews.llvm.org/D70729
2019-11-26 21:43:29 -05:00
Dávid Bolvanský ba4017670e [Diagnostics] Warn for comparison with string literals expanded from macro (PR44064)
Summary:
As noted in PR, we have a poor test coverage for this warning. I think macro support was just overlooked. GCC warns in these cases.
Clang missed a real bug in the code I am working with, GCC caught it.

Reviewers: aaron.ballman

Reviewed By: aaron.ballman

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D70624
2019-11-24 19:40:32 +01:00
Akira Hatanaka 825235c140 Revert "[Sema] Use the canonical type in function isVector"
This reverts commit a6150b48ce.
The commit broke a few neon CodeGen tests.
2019-11-22 13:48:39 -08:00
Akira Hatanaka a6150b48ce [Sema] Use the canonical type in function isVector
This fixes an assertion in Sema::CreateBuiltinBinOp that fails when one
of the vector operand's element type is a typedef of __fp16.

rdar://problem/55983556
2019-11-22 12:57:24 -08:00
Bill Wendling 2b795637b9 Fix typo to separate "-x" from warning flag. 2019-11-22 12:51:41 -08:00
Bill Wendling 9180f8a574 Don't report "main" as missing a prototype in freestanding mode
Summary:
A user may want to use freestanding mode with the standard "main" entry
point. It's not useful to warn about a missing prototype as it's not
typical to have a prototype for "main".

Reviewers: efriedma, aaron.ballman

Reviewed By: aaron.ballman

Subscribers: aaron.ballman, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D70588
2019-11-22 12:35:43 -08:00
Tim Northover 5cf58768cb Atomics: support min/max orthogonally
We seem to have been gradually growing support for atomic min/max operations
(exposing longstanding IR atomicrmw instructions). But until now there have
been gaps in the expected intrinsics. This adds support for the C11-style
intrinsics (i.e. taking _Atomic, rather than individually blessed by C11
standard), and the variants that return the new value instead of the original
one.

That way, people won't be misled by trying one form and it not working, and the
front-end is more friendly to people using _Atomic types, as we recommend.
2019-11-21 10:37:56 +00:00
Erik Pilkington d9957c7405 [Sema] Add a 'Semantic' parameter to Expr::isKnownToHaveBooleanValue
Some clients of this function want to know about any expression that is known
to produce a 0/1 value, and others care about expressions that are semantically
boolean.

This fixes a -Wswitch-bool regression I introduced in 8bfb353bb3, pointed out
by Chris Hamilton!
2019-11-20 16:29:31 -08:00
Sam McCall a433e7141f [AST] Attach comment in `/** doc */ typedef struct A {} B` to B as well as A.
Summary:
Semantically they're the same thing, and it's important when the underlying
struct is anonymous.

There doesn't seem to be a problem attaching the same comment to multiple things
as it already happens with `/** doc */ int a, b;`

This affects an Index test but the results look better (name present, USR points
to the typedef).

Fixes https://github.com/clangd/clangd/issues/189

Reviewers: kadircet, lh123

Subscribers: ilya-biryukov, jkorous, arphaman, usaxena95, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D70203
2019-11-18 11:09:23 +01:00
Anna Welker 2d739f98d8 [ARM] Allocatable Global Register Variables for ARM
Provides support for using r6-r11 as globally scoped
      register variables. This requires a -ffixed-rN flag
      in order to reserve rN against general allocation.

      If for a given GRV declaration the corresponding flag
      is not found, or the the register in question is the
      target's FP, we fail with a diagnostic.

      Differential Revision: https://reviews.llvm.org/D68862
2019-11-18 10:07:37 +00:00
Momchil Velikov aa6d48fa70 Implement target(branch-protection) attribute for AArch64
This patch implements `__attribute__((target("branch-protection=...")))`
in a manner, compatible with the analogous GCC feature:

https://gcc.gnu.org/onlinedocs/gcc-9.2.0/gcc/AArch64-Function-Attributes.html#AArch64-Function-Attributes

Differential Revision: https://reviews.llvm.org/D68711
2019-11-15 15:40:46 +00:00
Simon Tatham 9e37892773 [ARM,MVE] Add intrinsics for vector get/set lane.
This adds the `vgetq_lane` and `vsetq_lane` families, to copy between
a scalar and a specified lane of a vector.

One of the new `vgetq_lane` intrinsics returns a `float16_t`, which
causes a compile error if `%clang_cc1` doesn't get the option
`-fallow-half-arguments-and-returns`. The driver passes that option to
cc1 already, but I've had to edit all the explicit cc1 command lines
in the existing MVE intrinsics tests.

A couple of fixes are included for the code I wrote up front in
MveEmitter to support lane-index immediates (and which nothing has
tested until now): the type was wrong (`uint32_t` instead of `int`)
and the range was off by one.

I've also added a method of bypassing the default promotion to `i32`
that is done by the MveEmitter code generation: it's sensible to
promote short scalars like `i16` to `i32` if they're going to be
passed to custom IR intrinsics representing a machine instruction
operating on GPRs, but not if they're going to be passed to standard
IR operations like `insertelement` which expect the exact type.

Reviewers: ostannard, MarkMurrayARM, dmgreen

Reviewed By: dmgreen

Subscribers: kristof.beyls, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D70188
2019-11-15 09:53:58 +00:00
Yonghong Song dd16b3fe25 [BPF] Restrict preserve_access_index attribute to C only
This patch is a follow-up for commit 4e2ce228ae
  [BPF] Add preserve_access_index attribute for record definition
to restrict attribute for C only. A new test case is added
to check for this restriction.

Additional code polishing is done based on
Aaron Ballman's suggestion in https://reviews.llvm.org/D69759/new/.

Differential Revision: https://reviews.llvm.org/D70257
2019-11-14 14:14:59 -08:00
Yonghong Song 4e2ce228ae [BPF] Add preserve_access_index attribute for record definition
This is a resubmission for the previous reverted commit
9434360401 with the same subject. This commit fixed the
segfault issue and addressed additional review comments.

This patch introduced a new bpf specific attribute which can
be added to struct or union definition. For example,
  struct s { ... } __attribute__((preserve_access_index));
  union u { ... } __attribute__((preserve_access_index));
The goal is to simplify user codes for cases
where preserve access index happens for certain struct/union,
so user does not need to use clang __builtin_preserve_access_index
for every members.

The attribute has no effect if -g is not specified.

When the attribute is specified and -g is specified, any member
access defined by that structure or union, including array subscript
access and inner records, will be preserved through
  __builtin_preserve_{array,struct,union}_access_index()
IR intrinsics, which will enable relocation generation
in bpf backend.

The following is an example to illustrate the usage:
  -bash-4.4$ cat t.c
  #define __reloc__ __attribute__((preserve_access_index))
  struct s1 {
    int c;
  } __reloc__;

  struct s2 {
    union {
      struct s1 b[3];
    };
  } __reloc__;

  struct s3 {
    struct s2 a;
  } __reloc__;

  int test(struct s3 *arg) {
    return arg->a.b[2].c;
  }
  -bash-4.4$ clang -target bpf -g -S -O2 t.c

A relocation with access string "0:0:0:0:2:0" will be generated
representing access offset of arg->a.b[2].c.

forward declaration with attribute is also handled properly such
that the attribute is copied and populated in real record definition.

Differential Revision: https://reviews.llvm.org/D69759
2019-11-13 08:23:44 -08:00
Weverything 9740f9f0b6 Add -Wtautological-compare to -Wall
Some warnings in -Wtautological-compare subgroups are DefaultIgnore.
Adding this group to -Wmost, which is part of -Wall, will aid in their
discoverability.

Differential Revision: https://reviews.llvm.org/D69292
2019-11-12 14:36:57 -08:00
Tim Northover 44e5879f0f AArch64: add arm64_32 support to Clang. 2019-11-12 12:45:18 +00:00
Dávid Bolvanský 1da13237a4 [Diagnostics] Try to improve warning message for -Wreturn-type
Summary: I agree with https://easyaspi314.github.io/gcc-vs-clang.html?fbclid=IwAR1VA0qxiWVUusOQUv5z7JESS7ZpeJy-UqAI5mnJscofGLqXcqeErIUB2gU, current warning message is not very good. We should try to improve it..

Reviewers: rsmith, aaron.ballman, easyaspi314

Reviewed By: aaron.ballman

Subscribers: arphaman, Quuxplusone, mehdi_amini, hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D69762
2019-11-09 17:54:58 +01:00
Yonghong Song 9434360401 Revert "[BPF] Add preserve_access_index attribute for record definition"
This reverts commit 4a5aa1a7bf.

There are some other test failures. Investigate them first.
2019-11-09 08:32:44 -08:00
Yonghong Song 4a5aa1a7bf [BPF] Add preserve_access_index attribute for record definition
This patch introduced a new bpf specific attribute which can
be added to struct or union definition. For example,
  struct s { ... } __attribute__((preserve_access_index));
  union u { ... } __attribute__((preserve_access_index));
The goal is to simplify user codes for cases
where preserve access index happens for certain struct/union,
so user does not need to use clang __builtin_preserve_access_index
for every members.

The attribute has no effect if -g is not specified.

When the attribute is specified and -g is specified, any member
access defined by that structure or union, including array subscript
access and inner records, will be preserved through
  __builtin_preserve_{array,struct,union}_access_index()
IR intrinsics, which will enable relocation generation
in bpf backend.

The following is an example to illustrate the usage:
  -bash-4.4$ cat t.c
  #define __reloc__ __attribute__((preserve_access_index))
  struct s1 {
    int c;
  } __reloc__;

  struct s2 {
    union {
      struct s1 b[3];
    };
  } __reloc__;

  struct s3 {
    struct s2 a;
  } __reloc__;

  int test(struct s3 *arg) {
    return arg->a.b[2].c;
  }
  -bash-4.4$ clang -target bpf -g -S -O2 t.c

A relocation with access string "0:0:0:0:2:0" will be generated
representing access offset of arg->a.b[2].c.

forward declaration with attribute is also handled properly such
that the attribute is copied and populated in real record definition.

Differential Revision: https://reviews.llvm.org/D69759
2019-11-09 08:17:12 -08:00
Reid Kleckner 7177ce978e [SEH] Defer checking filter expression types until instantiaton
While here, wordsmith the error a bit. Now clang says:
  error: filter expression has non-integral type 'Foo'

Fixes PR43779

Reviewers: amccarth

Differential Revision: https://reviews.llvm.org/D69969
2019-11-07 14:52:04 -08:00
Dávid Bolvanský 01b10bc7b1 [Diagnostics] Teach -Wnull-dereference about address_space attribute
Summary:
Clang should not warn for:

> test.c:2:12: warning: indirection of non-volatile null pointer will be deleted,
>       not trap [-Wnull-dereference]
>     return *(int __attribute__((address_space(256))) *) 0;
>            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Solves PR42292.

Reviewers: aaron.ballman, rsmith

Reviewed By: aaron.ballman

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D69664
2019-11-07 22:43:27 +01:00
Simon Tatham 6c3fee47a6 [ARM,MVE] Add intrinsics for gather/scatter load/stores.
This patch adds two new families of intrinsics, both of which are
memory accesses taking a vector of locations to load from / store to.

The vldrq_gather_base / vstrq_scatter_base intrinsics take a vector of
base addresses, and an immediate offset to be added consistently to
each one. vldrq_gather_offset / vstrq_scatter_offset take a scalar
base address, and a vector of offsets to add to it. The
'shifted_offset' variants also multiply each offset by the element
size type, so that the vector is effectively of array indices.

At the IR level, these operations are represented by a single set of
four IR intrinsics: {gather,scatter} × {base,offset}. The other
details (signed/unsigned, shift, and memory element size as opposed to
vector element size) are all specified by IR intrinsic polymorphism
and immediate operands, because that made the selection job easier
than making a huge family of similarly named intrinsics.

I considered using the standard IR representations such as
llvm.masked.gather, but they're not a good fit. In order to use
llvm.masked.gather to represent a gather_offset load with element size
smaller than a pointer, you'd have to expand the <8 x i16> vector of
offsets into an <8 x i16*> vector of pointers, which would be split up
during legalization, so you'd spend most of your time undoing the mess
it had made. Also, ISel support for llvm.masked.gather would be easy
enough in a trivial way (you can expand it into a gather-base load
with a zero immediate offset), but instruction-selecting lots of
fiddly idioms back into all the _other_ MVE load instructions would be
much more work. So I think dedicated IR intrinsics are the more
sensible approach, at least for the moment.

On the clang tablegen side, I've added two new features to the
Tablegen source accepted by MveEmitter: a 'CopyKind' type node for
defining a type that varies with the parameter type (it lets you ask
for an unsigned integer type of the same width as the parameter), and
an 'unsignedflag' value node for passing an immediate IR operand which
is 0 for a signed integer type or 1 for an unsigned one. That lets me
write each kind of intrinsic just once and get all its subtypes and
immediate arguments generated automatically.

Also I've tweaked the handling of pointer-typed values in the code
generation part of MveEmitter: they're generated as Address rather
than Value (i.e. including an alignment) so that they can be given to
the ordinary IR load and store operations, but I'd omitted the code to
convert them back to Value when they're going to be used as an
argument to an IR intrinsic.

On the MC side, I've enhanced MVEVectorVTInfo so that it can tell you
not only the full assembly-language suffix for a given vector type
(like 's32' or 'u16') but also the numeric-only one used by store
instructions (just '32' or '16').

Reviewers: dmgreen

Subscribers: kristof.beyls, hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D69791
2019-11-06 09:01:42 +00:00
Guillaume Chatelet 5607ff12fa Fix missing memcpy builtin on ppc64be
See D68028
2019-10-29 16:35:32 +01:00
Guillaume Chatelet 98f3151a7d [clang] Add no_builtin attribute
Summary:
This is a follow up on https://reviews.llvm.org/D61634
This patch is simpler and only adds the no_builtin attribute.

Reviewers: tejohnson, courbet, theraven, t.p.northover, jdoerfert

Subscribers: mgrang, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D68028

This is a re-submit after it got reverted in https://reviews.llvm.org/rGbd8791610948 since the breakage doesn't seem to come from this patch.
2019-10-29 15:50:29 +01:00
Vlad Tsyrklevich ad531fff81 Revert "[clang] Add no_builtin attribute"
This reverts commit bd87916109. It was
causing ASan/MSan failures on the sanitizer buildbots.
2019-10-28 15:21:59 -07:00
Guillaume Chatelet bd87916109 [clang] Add no_builtin attribute
Summary:
This is a follow up on https://reviews.llvm.org/D61634
This patch is simpler and only adds the no_builtin attribute.

Reviewers: tejohnson, courbet, theraven, t.p.northover, jdoerfert

Subscribers: mgrang, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D68028
2019-10-28 17:30:11 +01:00
David Goldman 7a2b704bf0 [Sema][Typo Correction] Fix another infinite loop on ambiguity
See also: D67515

- For the given call expression we would end up repeatedly
   trying to transform the same expression over and over again

- Fix is to keep the old TransformCache when checking for ambiguity

Differential Revision: https://reviews.llvm.org/D69060
2019-10-25 13:20:27 -04:00
Simon Tatham 7c11da0cfd [clang] New __attribute__((__clang_arm_mve_alias)).
This allows you to declare a function with a name of your choice (say
`foo`), but have clang treat it as if it were a builtin function (say
`__builtin_foo`), by writing

  static __inline__ __attribute__((__clang_arm_mve_alias(__builtin_foo)))
  int foo(args);

I'm intending to use this for the ACLE intrinsics for MVE, which have
to be polymorphic on their argument types and also need to be
implemented by builtins. To avoid having to implement the polymorphism
with several layers of nested _Generic and make error reporting
hideous, I want to make all the user-facing intrinsics correspond
directly to clang builtins, so that after clang resolves
__attribute__((overloadable)) polymorphism it's already holding the
right BuiltinID for the intrinsic it selected.

However, this commit itself just introduces the new attribute, and
doesn't use it for anything.

To avoid unanticipated side effects if this attribute is used to make
aliases to other builtins, there's a restriction mechanism: only
(BuiltinID, alias) pairs that are approved by the function
ArmMveAliasValid() will be permitted. At present, that function
doesn't permit anything, because the Tablegen that will generate its
list of valid pairs isn't yet implemented. So the only test of this
facility is one that checks that an unapproved builtin _can't_ be
aliased.

Reviewers: dmgreen, miyuki, ostannard

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D67159
2019-10-24 16:33:13 +01:00
Richard Trieu 637af4cc37 Add -Wbitwise-conditional-parentheses to warn on mixing '|' and '&' with "?:"
Extend -Wparentheses to cover mixing bitwise-and and bitwise-or with the
conditional operator. There's two main cases seen with this:

unsigned bits1 = 0xf0 | cond ? 0x4 : 0x1;
unsigned bits2 = cond1 ? 0xf0 : 0x10 | cond2 ? 0x5 : 0x2;

// Intended order of evaluation:
unsigned bits1 = 0xf0 | (cond ? 0x4 : 0x1);
unsigned bits2 = (cond1 ? 0xf0 : 0x10) | (cond2 ? 0x5 : 0x2);

// Actual order of evaluation:
unsigned bits1 = (0xf0 | cond) ? 0x4 : 0x1;
unsigned bits2 = cond1 ? 0xf0 : ((0x10 | cond2) ? 0x5 : 0x2);

Differential Revision: https://reviews.llvm.org/D66043

llvm-svn: 375326
2019-10-19 01:47:49 +00:00
Richard Trieu 8b0d14a8f0 New tautological warning for bitwise-or with non-zero constant always true.
Taking a value and the bitwise-or it with a non-zero constant will always
result in a non-zero value. In a boolean context, this is always true.

if (x | 0x4) {}  // always true, intended '&'

This patch creates a new warning group -Wtautological-bitwise-compare for this
warning. It also moves in the existing tautological bitwise comparisons into
this group. A few other changes were needed to the CFGBuilder so that all bool
contexts would be checked. The warnings in -Wtautological-bitwise-compare will
be off by default due to using the CFG.

Fixes: https://bugs.llvm.org/show_bug.cgi?id=42666
Differential Revision: https://reviews.llvm.org/D66046

llvm-svn: 375318
2019-10-19 00:57:23 +00:00
Dmitry Mikulin f14642f2f1 Added support for "#pragma clang section relro=<name>"
Differential Revision: https://reviews.llvm.org/D68806

llvm-svn: 374934
2019-10-15 18:31:10 +00:00
Erich Keane add0786dba Fix test failure with 374562 on Hexagon
__builtin_assume_aligned takes a size_t which is a 32 bit int on
hexagon.  Thus, the constant gets converted to a 32 bit value, resulting
in 0 not being a power of 2.  This patch changes the constant being
passed to 2**30 so that it fails, but doesnt exceed 30 bits.

llvm-svn: 374569
2019-10-11 16:30:45 +00:00
Erich Keane f759395994 Reland r374450 with Richard Smith's comments and test fixed.
The behavior from the original patch has changed, since we're no longer
allowing LLVM to just ignore the alignment.  Instead, we're just
assuming the maximum possible alignment.

Differential Revision: https://reviews.llvm.org/D68824

llvm-svn: 374562
2019-10-11 14:59:44 +00:00
Nico Weber b556085d81 Revert 374450 "Fix __builtin_assume_aligned with too large values."
The test fails on Windows, with

  error: 'warning' diagnostics expected but not seen:
    File builtin-assume-aligned.c Line 62: requested alignment
        must be 268435456 bytes or smaller; assumption ignored
  error: 'warning' diagnostics seen but not expected:
    File builtin-assume-aligned.c Line 62: requested alignment
        must be 8192 bytes or smaller; assumption ignored

llvm-svn: 374456
2019-10-10 21:34:32 +00:00
Erich Keane 31e454c1ec Fix __builtin_assume_aligned with too large values.
Code to handle __builtin_assume_aligned was allowing larger values, but
would convert this to unsigned along the way. This patch removes the
EmitAssumeAligned overloads that take unsigned to do away with this
problem.

Additionally, it adds a warning that values greater than 1 <<29 are
ignored by LLVM.

Differential Revision: https://reviews.llvm.org/D68824

llvm-svn: 374450
2019-10-10 21:08:28 +00:00
Reid Kleckner 5e866e411c Add -fgnuc-version= to control __GNUC__ and other GCC macros
I noticed that compiling on Windows with -fno-ms-compatibility had the
side effect of defining __GNUC__, along with __GNUG__, __GXX_RTTI__, and
a number of other macros for GCC compatibility. This is undesirable and
causes Chromium to do things like mix __attribute__ and __declspec,
which doesn't work. We should have a positive language option to enable
GCC compatibility features so that we can experiment with
-fno-ms-compatibility on Windows. This change adds -fgnuc-version= to be
that option.

My issue aside, users have, for a long time, reported that __GNUC__
doesn't match their expectations in one way or another. We have
encouraged users to migrate code away from this macro, but new code
continues to be written assuming a GCC-only environment. There's really
nothing we can do to stop that. By adding this flag, we can allow them
to choose their own adventure with __GNUC__.

This overlaps a bit with the "GNUMode" language option from -std=gnu*.
The gnu language mode tends to enable non-conforming behaviors that we'd
rather not enable by default, but the we want to set things like
__GXX_RTTI__ by default, so I've kept these separate.

Helps address PR42817

Reviewed By: hans, nickdesaulniers, MaskRay

Differential Revision: https://reviews.llvm.org/D68055

llvm-svn: 374449
2019-10-10 21:04:25 +00:00
Yonghong Song 05e46979d2 [BPF] do compile-once run-everywhere relocation for bitfields
A bpf specific clang intrinsic is introduced:
   u32 __builtin_preserve_field_info(member_access, info_kind)
Depending on info_kind, different information will
be returned to the program. A relocation is also
recorded for this builtin so that bpf loader can
patch the instruction on the target host.
This clang intrinsic is used to get certain information
to facilitate struct/union member relocations.

The offset relocation is extended by 4 bytes to
include relocation kind.
Currently supported relocation kinds are
 enum {
    FIELD_BYTE_OFFSET = 0,
    FIELD_BYTE_SIZE,
    FIELD_EXISTENCE,
    FIELD_SIGNEDNESS,
    FIELD_LSHIFT_U64,
    FIELD_RSHIFT_U64,
 };
for __builtin_preserve_field_info. The old
access offset relocation is covered by
    FIELD_BYTE_OFFSET = 0.

An example:
struct s {
    int a;
    int b1:9;
    int b2:4;
};
enum {
    FIELD_BYTE_OFFSET = 0,
    FIELD_BYTE_SIZE,
    FIELD_EXISTENCE,
    FIELD_SIGNEDNESS,
    FIELD_LSHIFT_U64,
    FIELD_RSHIFT_U64,
};

void bpf_probe_read(void *, unsigned, const void *);
int field_read(struct s *arg) {
  unsigned long long ull = 0;
  unsigned offset = __builtin_preserve_field_info(arg->b2, FIELD_BYTE_OFFSET);
  unsigned size = __builtin_preserve_field_info(arg->b2, FIELD_BYTE_SIZE);
 #ifdef USE_PROBE_READ
  bpf_probe_read(&ull, size, (const void *)arg + offset);
  unsigned lshift = __builtin_preserve_field_info(arg->b2, FIELD_LSHIFT_U64);
 #if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
  lshift = lshift + (size << 3) - 64;
 #endif
 #else
  switch(size) {
  case 1:
    ull = *(unsigned char *)((void *)arg + offset); break;
  case 2:
    ull = *(unsigned short *)((void *)arg + offset); break;
  case 4:
    ull = *(unsigned int *)((void *)arg + offset); break;
  case 8:
    ull = *(unsigned long long *)((void *)arg + offset); break;
  }
  unsigned lshift = __builtin_preserve_field_info(arg->b2, FIELD_LSHIFT_U64);
 #endif
  ull <<= lshift;
  if (__builtin_preserve_field_info(arg->b2, FIELD_SIGNEDNESS))
    return (long long)ull >> __builtin_preserve_field_info(arg->b2, FIELD_RSHIFT_U64);
  return ull >> __builtin_preserve_field_info(arg->b2, FIELD_RSHIFT_U64);
}

There is a minor overhead for bpf_probe_read() on big endian.

The code and relocation generated for field_read where bpf_probe_read() is
used to access argument data on little endian mode:
        r3 = r1
        r1 = 0
        r1 = 4  <=== relocation (FIELD_BYTE_OFFSET)
        r3 += r1
        r1 = r10
        r1 += -8
        r2 = 4  <=== relocation (FIELD_BYTE_SIZE)
        call bpf_probe_read
        r2 = 51 <=== relocation (FIELD_LSHIFT_U64)
        r1 = *(u64 *)(r10 - 8)
        r1 <<= r2
        r2 = 60 <=== relocation (FIELD_RSHIFT_U64)
        r0 = r1
        r0 >>= r2
        r3 = 1  <=== relocation (FIELD_SIGNEDNESS)
        if r3 == 0 goto LBB0_2
        r1 s>>= r2
        r0 = r1
LBB0_2:
        exit

Compare to the above code between relocations FIELD_LSHIFT_U64 and
FIELD_LSHIFT_U64, the code with big endian mode has four more
instructions.
        r1 = 41   <=== relocation (FIELD_LSHIFT_U64)
        r6 += r1
        r6 += -64
        r6 <<= 32
        r6 >>= 32
        r1 = *(u64 *)(r10 - 8)
        r1 <<= r6
        r2 = 60   <=== relocation (FIELD_RSHIFT_U64)

The code and relocation generated when using direct load.
        r2 = 0
        r3 = 4
        r4 = 4
        if r4 s> 3 goto LBB0_3
        if r4 == 1 goto LBB0_5
        if r4 == 2 goto LBB0_6
        goto LBB0_9
LBB0_6:                                 # %sw.bb1
        r1 += r3
        r2 = *(u16 *)(r1 + 0)
        goto LBB0_9
LBB0_3:                                 # %entry
        if r4 == 4 goto LBB0_7
        if r4 == 8 goto LBB0_8
        goto LBB0_9
LBB0_8:                                 # %sw.bb9
        r1 += r3
        r2 = *(u64 *)(r1 + 0)
        goto LBB0_9
LBB0_5:                                 # %sw.bb
        r1 += r3
        r2 = *(u8 *)(r1 + 0)
        goto LBB0_9
LBB0_7:                                 # %sw.bb5
        r1 += r3
        r2 = *(u32 *)(r1 + 0)
LBB0_9:                                 # %sw.epilog
        r1 = 51
        r2 <<= r1
        r1 = 60
        r0 = r2
        r0 >>= r1
        r3 = 1
        if r3 == 0 goto LBB0_11
        r2 s>>= r1
        r0 = r2
LBB0_11:                                # %sw.epilog
        exit

Considering verifier is able to do limited constant
propogation following branches. The following is the
code actually traversed.
        r2 = 0
        r3 = 4   <=== relocation
        r4 = 4   <=== relocation
        if r4 s> 3 goto LBB0_3
LBB0_3:                                 # %entry
        if r4 == 4 goto LBB0_7
LBB0_7:                                 # %sw.bb5
        r1 += r3
        r2 = *(u32 *)(r1 + 0)
LBB0_9:                                 # %sw.epilog
        r1 = 51   <=== relocation
        r2 <<= r1
        r1 = 60   <=== relocation
        r0 = r2
        r0 >>= r1
        r3 = 1
        if r3 == 0 goto LBB0_11
        r2 s>>= r1
        r0 = r2
LBB0_11:                                # %sw.epilog
        exit

For native load case, the load size is calculated to be the
same as the size of load width LLVM otherwise used to load
the value which is then used to extract the bitfield value.

Differential Revision: https://reviews.llvm.org/D67980

llvm-svn: 374099
2019-10-08 18:23:17 +00:00
James Clarke 67f542aba7 [Diagnostics] Silence -Wsizeof-array-div for character buffers
Summary:
Character buffers are sometimes used to represent a pool of memory that
contains non-character objects, due to them being synonymous with a stream of
bytes on almost all modern architectures. Often, when interacting with hardware
devices, byte buffers are therefore used as an intermediary and so we can end
Character buffers are sometimes used to represent a pool of memory that
contains non-character objects, due to them being synonymous with a stream of
bytes on almost all modern architectures. Often, when interacting with hardware
devices, byte buffers are therefore used as an intermediary and so we can end
up generating lots of false-positives.

Moreover, due to the ability of character pointers to alias non-character
pointers, the strict aliasing violations that would generally be implied by the
calculations caught by the warning (if the calculation itself is in fact
correct) do not apply here, and so although the length calculation may be
wrong, that is the only possible issue.

Reviewers: rsmith, xbolva00, thakis

Reviewed By: xbolva00, thakis

Subscribers: thakis, lebedev.ri, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D68526

llvm-svn: 374035
2019-10-08 11:34:02 +00:00
David Bolvansky aaea76ba02 [Diagnostics] Emit better -Wbool-operation's warning message if we known that the result is always true
llvm-svn: 373973
2019-10-07 21:57:03 +00:00
David Bolvansky 559265c8da [Diagnostics] Use Expr::isKnownToHaveBooleanValue() to check bitwise negation of bool in languages without a bool type
Thanks for this advice, Richard Trieu!

llvm-svn: 373817
2019-10-05 08:02:11 +00:00
Yuanfang Chen 442ddffe13 [clang] fix a typo from r372531
Reviewers: xbolva00

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D68482

llvm-svn: 373792
2019-10-04 21:37:20 +00:00
Erik Pilkington f7766b1ed4 [Sema] Split out -Wformat-type-confusion from -Wformat-pedantic
The warnings now in -Wformat-type-confusion don't align with how we interpret
'pedantic' in clang, and don't belong in -pedantic.

Differential revision: https://reviews.llvm.org/D67775

llvm-svn: 373774
2019-10-04 19:20:27 +00:00
Sam McCall f44ca7f6eb Further improve -Wbool-operation bitwise negation message
llvm-svn: 373749
2019-10-04 14:11:05 +00:00
David Bolvansky 5e851ad6c1 [NFCI] Improve the -Wbool-operation's warning message
Based on the request from the post commit review. Also added one new test.

llvm-svn: 373743
2019-10-04 12:55:13 +00:00
David Bolvansky b4ee523ffc [Diagnostics] Bitwise negation of a boolean expr always evaluates to true; warn with -Wbool-operation
Requested here:
http://lists.llvm.org/pipermail/cfe-dev/2019-October/063452.html

llvm-svn: 373614
2019-10-03 15:17:59 +00:00
David Bolvansky 00d632e089 [Diagnostics] Make -Wenum-compare-conditional off by default
Too many false positives, eg. in Chromium.

llvm-svn: 373371
2019-10-01 18:12:13 +00:00
David Bolvansky 362055d1fa [Diagnostics] Move warning into the subgroup (-Wenum-compare-conditional)
llvm-svn: 373345
2019-10-01 15:44:38 +00:00
David Bolvansky 471910d754 [Diagnostics] Warn if enumeration type mismatch in conditional expression
Summary:
- Useful warning
- GCC compatibility (GCC warns in C++ mode)

Reviewers: rsmith, aaron.ballman

Reviewed By: aaron.ballman

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D67919

llvm-svn: 373252
2019-09-30 19:55:50 +00:00
David Bolvansky 275e4df115 [Diagnostics] Handle tautological left shifts in boolean context
llvm-svn: 372749
2019-09-24 13:14:18 +00:00
David Bolvansky 849fd28cf0 [Diagnostics] Do not diagnose unsigned shifts in boolean context (-Wint-in-bool-context)
I was looking at old GCC's patch. Current "trunk" version avoids warning for unsigned case, GCC warns only for signed shifts.

llvm-svn: 372708
2019-09-24 09:14:33 +00:00
David Bolvansky 28b38c277a [Diagnostics] Warn for enum constants in bool context (-Wint-in-bool-context; GCC compatibility)
Extracted from D63082.

llvm-svn: 372664
2019-09-23 22:09:49 +00:00
David Bolvansky 84ea41fd17 [Diagnostics] Warn if '<<' in bool context with -Wint-in-bool-context (GCC compatibility)
Extracted from D63082, addressed review comments related to a warning message.

llvm-svn: 372612
2019-09-23 14:21:08 +00:00
David Bolvansky 116e6cf36e [Diagnostics] Avoid -Wsizeof-array-div when dividing the size of a nested array by the size of the deepest base type
llvm-svn: 372600
2019-09-23 12:54:35 +00:00
Craig Topper e4c1765124 [X86] Require last argument to LWPINS/LWPVAL builtins to be an ICE. Add ImmArg to the llvm intrinsics.
Update the isel patterns to use timm instead of imm.

llvm-svn: 372534
2019-09-22 23:48:50 +00:00
David Bolvansky fb218170b4 [Diagnostics] Warn if ?: with integer constants always evaluates to true
Extracted from D63082. GCC has this warning under -Wint-in-bool-context, but as noted in the D63082's review, we should put it under TautologicalConstantCompare.

llvm-svn: 372531
2019-09-22 22:00:48 +00:00
Yonghong Song 91d5c2a035 [CLANG][BPF] permit any argument type for __builtin_preserve_access_index()
Commit c15aa241f8 ("[CLANG][BPF] change __builtin_preserve_access_index()
signature") changed the builtin function signature to
  PointerT __builtin_preserve_access_index(PointerT ptr)
with a pointer type as the argument/return type, where argument and
return types must be the same.

There is really no reason for this constraint. The builtin just
presented a code region so that IR builtins
  __builtin_{array, struct, union}_preserve_access_index
can be applied.

This patch removed the pointer type restriction to permit any
argument type as long as it is permitted by the compiler.

Differential Revision: https://reviews.llvm.org/D67883

llvm-svn: 372516
2019-09-22 17:33:48 +00:00
Richard Trieu 4c05de8c1d Merge and improve code that detects same value in comparisons.
-Wtautological-overlap-compare and self-comparison from -Wtautological-compare
relay on detecting the same operand in different locations.  Previously, each
warning had it's own operand checker.  Now, both are merged together into
one function that each can call.  The function also now looks through member
access and array accesses.

Differential Revision: https://reviews.llvm.org/D66045

llvm-svn: 372453
2019-09-21 03:02:26 +00:00
Richard Trieu 6541c7988b Improve -Wtautological-overlap-compare
Allow this warning to detect a larger number of constant values, including
negative numbers, and handle non-int types better.

Differential Revision: https://reviews.llvm.org/D66044

llvm-svn: 372448
2019-09-21 02:37:10 +00:00
Yonghong Song c15aa241f8 [CLANG][BPF] change __builtin_preserve_access_index() signature
The clang intrinsic __builtin_preserve_access_index() currently
has signature:
  const void * __builtin_preserve_access_index(const void * ptr)

This may cause compiler warning when:
  - parameter type is "volatile void *" or "const volatile void *", or
  - the assign-to type of the intrinsic does not have "const" qualifier.
Further, this signature does not allow dereference of the
builtin result pointer as it is a "const void *" type, which
adds extra step for the user to do type casting.

Let us change the signature to:
  PointerT __builtin_preserve_access_index(PointerT ptr)
such that the result and argument types are the same.
With this, directly dereferencing the builtin return value
becomes possible.

Differential Revision: https://reviews.llvm.org/D67734

llvm-svn: 372294
2019-09-19 02:59:43 +00:00
Erik Pilkington 5741d19f04 [Sema] Suppress -Wformat diagnostics for bool types when printed using %hhd
Also, add a diagnostic under -Wformat for printing a boolean value as a
character.

rdar://54579473

Differential revision: https://reviews.llvm.org/D66856

llvm-svn: 372247
2019-09-18 19:05:14 +00:00
Erik Pilkington 5c62152275 [Sema] Split of versions of -Wimplicit-{float,int}-conversion for Objective-C BOOL
Also, add a diagnostic group, -Wobjc-signed-char-bool, to control all these
related diagnostics.

rdar://51954400

Differential revision: https://reviews.llvm.org/D67559

llvm-svn: 372183
2019-09-17 21:11:51 +00:00
Erik Pilkington a1e29a3407 Use 'BOOL' instead of BOOL in diagnostic messages
Type names should be enclosed in single quotes.

llvm-svn: 372152
2019-09-17 18:02:45 +00:00
Richard Smith 9864269a0d Fix reliance on lax vector conversions in tests for x86 intrinsics.
llvm-svn: 372062
2019-09-17 03:56:28 +00:00
David Bolvansky b8185153f3 [Diagnostics] Added silence note for -Wsizeof-array-div; suggest extra parens
llvm-svn: 371924
2019-09-14 19:38:55 +00:00
David Goldman 6d18650421 [Sema][Typo Correction] Fix potential infite loop on ambiguity checks
Summary:
This fixes a bug introduced in D62648, where Clang could infinite loop
if it became stuck on a single TypoCorrection when it was supposed to
be testing ambiguous corrections. Although not a common case, it could
happen if there are multiple possible corrections with the same edit
distance.

The fix is simply to wipe the TypoExpr from the `TransformCache` so that
the call to `TransformTypoExpr` doesn't use the `CachedEntry`.

Reviewers: rsmith

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D67515

llvm-svn: 371859
2019-09-13 14:43:24 +00:00
Richard Smith c624510f13 For PR17164: split -fno-lax-vector-conversion into three different
levels:

 -- none: no lax vector conversions [new GCC default]
 -- integer: only conversions between integer vectors [old GCC default]
 -- all: all conversions between same-size vectors [Clang default]

For now, Clang still defaults to "all" mode, but per my proposal on
cfe-dev (2019-04-10) the default will be changed to "integer" as soon as
that doesn't break lots of testcases. (Eventually I'd like to change the
default to "none" to match GCC and general sanity.)

Following GCC's behavior, the driver flag -flax-vector-conversions is
translated to -flax-vector-conversions=integer.

This reinstates r371805, reverted in r371813, with an additional fix for
lldb.

llvm-svn: 371817
2019-09-13 06:02:15 +00:00
Jonas Devlieghere 4aaa77e48d Revert "For PR17164: split -fno-lax-vector-conversion into three different"
This breaks the LLDB build. I tried reaching out to Richard, but haven't
gotten a reply yet.

llvm-svn: 371813
2019-09-13 05:16:59 +00:00
Richard Smith 49c4e58b75 For PR17164: split -fno-lax-vector-conversion into three different
levels:

 -- none: no lax vector conversions [new GCC default]
 -- integer: only conversions between integer vectors [old GCC default]
 -- all: all conversions between same-size vectors [Clang default]

For now, Clang still defaults to "all" mode, but per my proposal on
cfe-dev (2019-04-10) the default will be changed to "integer" as soon as
that doesn't break lots of testcases. (Eventually I'd like to change the
default to "none" to match GCC and general sanity.)

Following GCC's behavior, the driver flag -flax-vector-conversions is
translated to -flax-vector-conversions=integer.

llvm-svn: 371805
2019-09-13 02:20:00 +00:00
David Bolvansky 82d9e0e122 [NFC] Added triple to test file to avoid arm buildbots failures
llvm-svn: 371646
2019-09-11 18:55:56 +00:00
David Bolvansky 3240ad4ced [Diagnostics] Add -Wsizeof-array-div
Summary: Clang version of https://www.viva64.com/en/examples/v706/

Reviewers: rsmith

Differential Revision: https://reviews.llvm.org/D67287

llvm-svn: 371605
2019-09-11 10:59:47 +00:00
Reid Kleckner 7b4237d3cc Emit -Wmicrosoft-enum-value warning instead of error in MS ABI
Summary:
The first NFC change is to replace a getCXXABI().isMicrosoft() check
with getTriple().isWindowsMSVCEnvironment(). This code takes effect in
non-C++ compilations, so it doesn't make sense to check the C++ ABI. In
the MS ABI, enums are always considered to be "complete" because the
underlying type of an unfixed enum will always be 'int'. This behavior
was moved from -fms-compatibility to MS ABI back in r249656.

The second change is functional, and it downgrades an error to a warning
when the MS ABI is used rather than only under -fms-compatibility. The
reasoning is that it's unreasonable for the following code to reject the
following code for all MS ABI targets with -fno-ms-compatibility:
  enum Foo { Foo_Val = 0xDEADBEEF };
This is valid code for any other target, but in the MS ABI, Foo_Val just
happens to be negative. With this change, clang emits a
-Wmicrosoft-enum-value warning on this code, but compiles it without
error.

Fixes PR38478

Reviewers: hans, rsmith, STL_MSFT

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D67304

llvm-svn: 371581
2019-09-11 01:01:06 +00:00
Richard Smith 045b2270ce When evaluating a __builtin_constant_p conditional, always enter
constant-folding mode regardless of the original evaluation mode.

In order for this to be correct, we need to track whether we're checking
for a potential constant expression or checking for undefined behavior
separately from the evaluation mode enum, since we don't want to clobber
those states when entering constant-folding mode.

llvm-svn: 371557
2019-09-10 21:24:09 +00:00
Craig Topper ce2cb0f09e [X86] Allow _MM_FROUND_CUR_DIRECTION and _MM_FROUND_NO_EXC to be used together on instructions that only support SAE and not embedded rounding.
Current for SAE instructions we only allow _MM_FROUND_CUR_DIRECTION(bit 2) or _MM_FROUND_NO_EXC(bit 3) to be used as the immediate passed to the inrinsics. But these instructions don't perform rounding so _MM_FROUND_CUR_DIRECTION is just sort of a default placeholder when you don't want to suppress exceptions. Using _MM_FROUND_NO_EXC by itself is really bit equivalent to (_MM_FROUND_NO_EXC | _MM_FROUND_TO_NEAREST_INT) since _MM_FROUND_TO_NEAREST_INT is 0. Since we aren't rounding on these instructions we should also accept (_MM_FROUND_CUR_DIRECTION | _MM_FROUND_NO_EXC) as equivalent to (_MM_FROUND_NO_EXC). icc allows this, but gcc does not.

Differential Revision: https://reviews.llvm.org/D67289

llvm-svn: 371430
2019-09-09 17:48:05 +00:00
David Bolvansky 454e40eaf3 [NFCI] Unbreak buildbots
llvm-svn: 371226
2019-09-06 16:30:44 +00:00
David Bolvansky d1cc181d03 [NFC] Added new tests for r371222
llvm-svn: 371223
2019-09-06 16:18:18 +00:00
David Bolvansky fd07568074 [Diagnostics] Refactor code for -Wsizeof-pointer-div, catch more cases; also add -Wsizeof-array-div
Previously, -Wsizeof-pointer-div failed to catch:
const int *r;
sizeof(r) / sizeof(int);

Now fixed.
Also introduced -Wsizeof-array-div which catches bugs like:
sizeof(r) / sizeof(short);

(Array element type does not match type of sizeof operand).

llvm-svn: 371222
2019-09-06 16:12:48 +00:00
David Candler a59bffb576 [ARM] Add support for the s,j,x,N,O inline asm constraints
A number of inline assembly constraints are currently supported by LLVM, but rejected as invalid by Clang:

Target independent constraints:

s: An integer constant, but allowing only relocatable values

ARM specific constraints:

j: An immediate integer between 0 and 65535 (valid for MOVW)
x: A 32, 64, or 128-bit floating-point/SIMD register: s0-s15, d0-d7, or q0-q3
N: An immediate integer between 0 and 31 (Thumb1 only)
O: An immediate integer which is a multiple of 4 between -508 and 508. (Thumb1 only)

This patch adds support to Clang for the missing constraints along with some checks to ensure that the constraints are used with the correct target and Thumb mode, and that immediates are within valid ranges (at least where possible). The constraints are already implemented in LLVM, but just a couple of minor corrections to checks (V8M Baseline includes MOVW so should work with 'j', 'N' and 'O' shouldn't be valid in Thumb2) so that Clang and LLVM are in line with each other and the documentation.

Differential Revision: https://reviews.llvm.org/D65863

Change-Id: I18076619e319bac35fbb60f590c069145c9d9a0a
llvm-svn: 371079
2019-09-05 15:17:25 +00:00
Gabor Horvath 6f98400189 [LifetimeAnalysis] Fix some false positives
Differential Revision: https://reviews.llvm.org/D66806

llvm-svn: 370773
2019-09-03 16:17:24 +00:00
Dmitri Gribenko d94b42f422 [Wdocumentation] fixes an assertion failure with typedefed function and block pointer
Summary:
The assertion happens when compiling with -Wdocumentation with variable declaration to a typedefed function pointer. I not too familiar with the ObjC syntax but first two tests assert without this patch.

Fixes https://bugs.llvm.org/show_bug.cgi?id=42844

Reviewers: gribozavr

Reviewed By: gribozavr

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D66706

llvm-svn: 370677
2019-09-02 18:24:33 +00:00
Richard Smith 5030928d60 [c++20] Implement semantic restrictions for C++20 designated
initializers.

This has some interesting interactions with our existing extensions to
support C99 designated initializers as an extension in C++. Those are
resolved as follows:

 * We continue to permit the full breadth of C99 designated initializers
   in C++, with the exception that we disallow a partial overwrite of an
   initializer with a non-trivially-destructible type. (Full overwrite
   is OK, because we won't run the first initializer at all.)

 * The C99 extensions are disallowed in SFINAE contexts and during
   overload resolution, where they could change the meaning of valid
   programs.

 * C++20 disallows reordering of initializers. We only check for that for
   the simple cases that the C++20 rules permit (designators of the form
   '.field_name =' and continue to allow reordering in other cases).
   It would be nice to improve this behavior in future.

 * All C99 designated initializer extensions produce a warning by
   default in C++20 mode. People are going to learn the C++ rules based
   on what Clang diagnoses, so it's important we diagnose these properly
   by default.

 * In C++ <= 17, we apply the C++20 rules rather than the C99 rules, and
   so still diagnose C99 extensions as described above. We continue to
   accept designated C++20-compatible initializers in C++ <= 17 silently
   by default (but naturally still reject under -pedantic-errors).

This is not a complete implementation of P0329R4. In particular, that
paper introduces new non-C99-compatible syntax { .field { init } }, and
we do not support that yet.

This is based on a previous patch by Don Hinton, though I've made
substantial changes when addressing the above interactions.

Differential Revision: https://reviews.llvm.org/D59754

llvm-svn: 370544
2019-08-30 22:52:55 +00:00
Richard Smith 33e9be6c8b Refactor InitListChecker to check only a single (explicit) initializer
list, rather than recursively checking multiple lists in C.

This simplification is in preparation for making InitListChecker
maintain more state that's specific to the explicit initializer list,
particularly when handling designated initialization.

llvm-svn: 370418
2019-08-29 22:49:33 +00:00
Artem Dergachev e5c0994ddf [CFG] Fix CFG for statement-expressions in return values.
We're building the CFG from bottom to top, so when the return-value expression
has a non-trivial CFG on its own, we need to continue building from the entry
to the return-value expression CFG rather than from the block to which
we've just appended the return statement.

Fixes a false positive warning "control may reach end of non-void function".

llvm-svn: 370406
2019-08-29 20:37:28 +00:00
Aaron Ballman 1d93522056 Replace some custom C11 extension warnings with the generic warning.
llvm-svn: 370066
2019-08-27 14:41:39 +00:00
Aaron Ballman 99178faf59 Quote the token being diagnosed for C11 extensions.
llvm-svn: 370059
2019-08-27 13:47:51 +00:00
Aaron Ballman 3c5bd65154 Fixing a weird copy-pasta to get bots back to green.
llvm-svn: 369960
2019-08-26 20:46:20 +00:00
Aaron Ballman 33d563e59e Reword the C11 extension diagnostic.
This makes it more consistent with other language extension diagnostics.

llvm-svn: 369957
2019-08-26 20:29:08 +00:00
Aaron Ballman 774bd6ef1c Diagnose use of _Thread_local as an extension when not in C11 mode.
llvm-svn: 369954
2019-08-26 19:44:07 +00:00
Dmitri Gribenko c955e4a910 [Wdocumentation] improve wording of a warning message
Based on @davezarzycki remarks in D64696 improved the wording of the warning
message.

Differential Revision: https://reviews.llvm.org/D66700

Patch by Mark de Wever.

llvm-svn: 369873
2019-08-25 18:20:18 +00:00
Gabor Horvath 665a64265e Fix a test to test what the name suggest.
llvm-svn: 369820
2019-08-23 22:26:49 +00:00
Gabor Horvath 6379e5c8a4 [LifetimeAnalysis] Make it possible to disable the new warnings
llvm-svn: 369817
2019-08-23 22:21:33 +00:00
Nathan Huckleberry cc01d6421f [Sema] Don't warn on printf('%hd', [char]) (PR41467)
Summary: Link: https://bugs.llvm.org/show_bug.cgi?id=41467

Reviewers: rsmith, nickdesaulniers, aaron.ballman, lebedev.ri

Reviewed By: nickdesaulniers, aaron.ballman, lebedev.ri

Subscribers: lebedev.ri, nickdesaulniers, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D66186

llvm-svn: 369791
2019-08-23 18:01:57 +00:00
David Goldman fd4d77707f [Sema][Typo] Fix assertion failure for expressions with multiple typos
Summary:
As Typo Resolution can create new TypoExprs while resolving typos,
it is necessary to recurse through the expression to search for more
typos.

This should fix the assertion failure in `clang::Sema::~Sema()`:
  `DelayedTypos.empty() && "Uncorrected typos!"`

Notes:
- In case some TypoExprs are created but thrown away, Sema
  now has a Vector that is used to keep track of newly created
  typos.
- For expressions with multiple typos, we only give suggestions
  if we are able to resolve all typos in the expression
- This patch is similar to D37521 except that it does not eagerly
  commit to a correction for the first typo in the expression.
  Instead, it will search for corrections which fix all of the
  typos in the expression.

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D62648

llvm-svn: 369427
2019-08-20 19:03:15 +00:00
Nathan Huckleberry 1e0affb6e5 [Attr] Support _attribute__ ((fallthrough))
Summary: Fixed extraneous matches of non-NullStmt

Reviewers: aaron.ballman, rsmith, efriedma, xbolva00

Reviewed By: aaron.ballman, rsmith, xbolva00

Subscribers: riccibruno, arphaman, ziangwan, ojeda, xbolva00, nickdesaulniers, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D64838

llvm-svn: 369414
2019-08-20 17:16:49 +00:00
Gabor Horvath eaee4de503 [LifetimeAnalysis] Add support for free functions
Differential Revision: https://reviews.llvm.org/D66303

llvm-svn: 369408
2019-08-20 16:45:06 +00:00
Stephan Bergmann 982b105d2f Rudimentary support for Doxygen \retval command
...so that at least a preceding \param etc. that lacks a description gets a
-Wdocumentation warning (instead of erroneously treating the \retval ... text as
its paragraph).

Differential Revision: https://reviews.llvm.org/D66350

llvm-svn: 369345
2019-08-20 08:36:21 +00:00