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.
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
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
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
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
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
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.
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
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
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
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.
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
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.
Summary: We mark these decls as invalid.
Reviewers: sammccall
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D77037
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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.
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
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
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
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
Erich Keane