Commit Graph

8782 Commits

Author SHA1 Message Date
Richard Smith 892df30a7f Fix interaction of `constinit` and `weak`.
We previously took a shortcut and said that weak variables never have
constant initializers (because those initializers are never correct to
use outside the variable). We now say that weak variables can have
constant initializers, but are never usable in constant expressions.
2020-09-30 10:49:50 -07:00
Xiangling Liao 3a7487f903 [FE] Use preferred alignment instead of ABI alignment for complete object when applicable
On some targets, preferred alignment is larger than ABI alignment in some cases. For example,
on AIX we have special power alignment rules which would cause that. Previously, to support
those cases, we added a “PreferredAlignment” field in the `RecordLayout` to store the AIX
special alignment values in “PreferredAlignment” as the community suggested.

However, that patch alone is not enough. There are places in the Clang where `PreferredAlignment`
should have been used instead of ABI-specified alignment. This patch is aimed at fixing those
spots.

Differential Revision: https://reviews.llvm.org/D86790
2020-09-30 10:48:28 -04:00
Xiangling Liao 944691f0b7 [NFC][FE] Replace TypeSize with StorageUnitSize
On some targets like AIX, last bitfield size is not always equal to last
bitfield type size. Some bitfield like bool will have the same alignment
as [unsigned]. So we'd like to use a more general term `StorageUnit` to
replace type in this field.

Differential Revision: https://reviews.llvm.org/D88260
2020-09-30 10:32:53 -04:00
John McCall 984744a131 Fix a variety of minor issues with ObjC method mangling:
- Fix a memory leak accidentally introduced yesterday by using CodeGen's
  existing mangling context instead of creating a new context afresh.

- Move GNU-runtime ObjC method mangling into the AST mangler; this will
  eventually be necessary to support direct methods there, but is also
  just the right architecture.

- Make the Apple-runtime method mangling work properly when given an
  interface declaration, fixing a bug (which had solidified into a test)
  where mangling a category method from the interface could cause it to
  be mangled as if the category name was a class name.  (Category names
  are namespaced within their class and have no global meaning.)

- Fix a code cross-reference in dsymutil.

Based on a patch by Ellis Hoag.
2020-09-29 19:51:53 -04:00
Ellis Hoag 98ef7e29b0 This reduces code duplication between CGObjCMac.cpp and Mangle.cpp
for generating the mangled name of an Objective-C method.

This has no intended functionality change.

https://reviews.llvm.org/D88329
2020-09-29 02:26:51 -04:00
Richard Smith df2a1f2aab Add profiling support for APValues.
For C++20 P0732R2; unused so far. Will be used and tested by a follow-on
commit.
2020-09-27 20:05:39 -07:00
Richard Smith 9dcd96f728 Canonicalize declaration pointers when forming APValues.
References to different declarations of the same entity aren't different
values, so shouldn't have different representations.

Recommit of e6393ee813 with fixed handling
for weak declarations. We now look for attributes on the most recent
declaration when determining whether a declaration is weak. (Second
recommit with further fixes for mishandling of weak declarations. Our
behavior here is fundamentally unsound -- see PR47663 -- but this
approach attempts to not make things worse.)
2020-09-27 19:05:26 -07:00
Serge Pavlov 6314f412a8 [FPEnv] Evaluate constant expressions under non-default rounding modes
The change implements evaluation of constant floating point expressions
under non-default rounding modes. The main objective was to support
evaluation of global variable initializers, where constant rounding mode
may be specified by `#pragma STDC FENV_ROUND`.

Differential Revision: https://reviews.llvm.org/D87822
2020-09-26 17:59:39 +07:00
Bill Wendling 34ca5b3392 Remove stale assert.
This is triggered during serialization. The test is for modules, but
will occur for any serialization effort using asm goto.

Reviewed By: nickdesaulniers, jyknight

Differential Revision: https://reviews.llvm.org/D88195
2020-09-24 13:59:42 -07:00
Sam McCall 1ad94624f8 [AST] Use data-recursion when building ParentMap, avoid stack overflow.
The following crashes on my system before this patch, but not after:

  void foo(int i) {
    switch (i) {
      case 1:
      case 2:
      ... 100000 cases ...
        ;
    }
  }

  clang-query -c="match stmt(hasAncestor(stmt()))" deep.c

I'm not sure it's actually a sane testcase to run though, it's pretty slow :-)

Differential Revision: https://reviews.llvm.org/D88222
2020-09-24 22:49:44 +02:00
Reid Kleckner b62fd436a3 Revert "Recommit [NFC] Refactor DiagnosticBuilder and PartialDiagnostic"
This reverts commit 8e780a1653.

DiagnosticBuilder is a value type, created on the stack everywhere. IMO
we should not be adding a vtable to it, and making very operator<< use a
virtual interface. There are other feasible designs for implementing
this. The original review, D84362, was approved by @tra, who is
responsible for Clang's CUDA support, but it wasn't reviewed by @rsmith
or anyone responsible for clang's diagnostic library.
2020-09-24 11:16:55 -07:00
Yaxun (Sam) Liu 8e780a1653 Recommit [NFC] Refactor DiagnosticBuilder and PartialDiagnostic
This recommits 829d14ee0a.

The patch was reverted due to a regression in some CUDA app
which was thought to be caused by this patch. However, investigation
showed that the regression was due to some other issues, therefore
recommit this patch.
2020-09-23 16:55:00 -04:00
Leonard Chan 15d94a7d0f Revert "Canonicalize declaration pointers when forming APValues."
This reverts commit 905b9ca26c.

Reverting because this strips `weak` attributes off function
declarations, leading to the linker error we see at
https://ci.chromium.org/p/fuchsia/builders/ci/clang_toolchain.fuchsia-arm64-debug-subbuild/b8868932035091473008.

See https://reviews.llvm.org/rG905b9ca26c94 for reproducer details.
2020-09-22 17:40:53 -07:00
shafik 6807f244fa [ASTImporter] Modifying ImportDeclContext(...) to ensure that we also handle the case when the FieldDecl is an ArrayType whose ElementType is a RecordDecl
When we fixed ImportDeclContext(...) in D71378 to make sure we complete each
FieldDecl of a RecordDecl when we are importing the definition we missed the
case where a FeildDecl was an ArrayType whose ElementType is a record.

This fix was motivated by a codegen crash during LLDB expression parsing. Since
we were not importing the definition we were crashing during layout which
required all the records be defined.

Differential Revision: https://reviews.llvm.org/D86660
2020-09-21 14:57:00 -07:00
Raphael Isemann 7c4575e15f [ASTImporter] Refactor IsStructurallyEquivalent's Decl overloads to be more consistent
There are several `::IsStructurallyEquivalent` overloads for Decl subclasses
that are used for comparing declarations. There is also one overload that takes
just two Decl pointers which ends up queuing the passed Decls to be later
compared in `CheckKindSpecificEquivalence`.

`CheckKindSpecificEquivalence` implements the dispatch logic for the different
Decl subclasses. It is supposed to hand over the queued Decls to the
subclass-specific `::IsStructurallyEquivalent` overload that will actually
compare the Decl instance. It also seems to implement a few pieces of actual
node comparison logic inbetween the dispatch code.

This implementation causes that the different overloads of
`::IsStructurallyEquivalent` do different (and sometimes no) comparisons
depending on which overload of `::IsStructurallyEquivalent` ends up being
called.

For example, if I want to compare two FieldDecl instances, then I could either
call the `::IsStructurallyEquivalent` with `Decl *` or with `FieldDecl *`
parameters. The overload that takes FieldDecls is doing a correct comparison.
However, the `Decl *` overload just queues the Decl pair.
`CheckKindSpecificEquivalence` has no dispatch logic for `FieldDecl`, so it
always returns true and never does any actual comparison.

On the other hand, if I try to compare two FunctionDecl instances the two
possible overloads of `::IsStructurallyEquivalent` have the opposite behaviour:
The overload that takes `FunctionDecl` pointers isn't comparing the names of the
FunctionDecls while the overload taking a plain `Decl` ends up comparing the
function names (as the comparison logic for that is implemented in
`CheckKindSpecificEquivalence`).

This patch tries to make this set of functions more consistent by making
`CheckKindSpecificEquivalence` a pure dispatch function without any
subclass-specific comparison logic. Also the dispatch logic is now autogenerated
so it can no longer miss certain subclasses.

The comparison code from `CheckKindSpecificEquivalence` is moved to the
respective `::IsStructurallyEquivalent` overload so that the comparison result
no longer depends if one calls the `Decl *` overload or the overload for the
specific subclass. The only difference is now that the `Decl *` overload is
queuing the parameter while the subclass-specific overload is directly doing the
comparison.

`::IsStructurallyEquivalent` is an implementation detail and I don't think the
behaviour causes any bugs in the current implementation (as carefully calling
the right overload for the different classes works around the issue), so the
test for this change is that I added some new code for comparing `MemberExpr`.
The new comparison code always calls the dispatching overload and it previously
failed as the dispatch didn't support FieldDecls.

Reviewed By: martong, a_sidorin

Differential Revision: https://reviews.llvm.org/D87619
2020-09-21 16:41:00 +02:00
Haojian Wu af29591650 [AST] Reduce the size of TemplateArgumentLocInfo.
allocate the underlying data of Template kind separately, this would reduce AST
memory usage

- TemplateArgumentLocInfo 24 => 8 bytes
- TemplateArgumentLoc  48 => 32 bytes
- DynTypeNode 56 => 40 bytes

ASTContext::.getASTAllocatedMemory changes:
  SemaDecl.cpp 255.5 MB => 247.5MB
  SemaExpr.cpp 293.5 MB => 283.5MB

Differential Revision: https://reviews.llvm.org/D87080
2020-09-21 13:08:53 +02:00
Haojian Wu f8f1e5fb39 [AST] Fix dependence-bits for CXXDefaultInitExpr.
Reviewed By: sammccall

Differential Revision: https://reviews.llvm.org/D87382
2020-09-21 08:47:01 +02:00
Richard Smith aa769358d8 [c++20] Consistent with the intent to allow all plausible types in
non-type template parameters, permit vector types.
2020-09-20 23:09:26 -07:00
Richard Smith 0cd73dbe2c [c++20] For P1907R1: Add checking for structural types for non-type
template parameters.

No support for the new kinds of non-type template argument yet.

This is not entirely NFC for prior language modes: we have historically
incorrectly accepted rvalue references as the types of non-type template
parameters. Such invalid code is now rejected.
2020-09-20 20:20:52 -07:00
Yaxun (Sam) Liu 829d14ee0a Revert "[NFC] Refactor DiagnosticBuilder and PartialDiagnostic"
This reverts commit ee5519d323.
2020-09-17 13:56:09 -04:00
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
Richard Smith 905b9ca26c Canonicalize declaration pointers when forming APValues.
References to different declarations of the same entity aren't different
values, so shouldn't have different representations.

Recommit of e6393ee813 with fixed
handling for weak declarations. We now look for attributes on the most
recent declaration when determining whether a declaration is weak.
2020-09-16 18:11:18 -07:00
Yaxun (Sam) Liu ee5519d323 [NFC] Refactor DiagnosticBuilder and PartialDiagnostic
PartialDiagnostic misses some functions compared to DiagnosticBuilder.

This patch refactors DiagnosticBuilder and PartialDiagnostic, extracts
the common functionality so that the streaming << operators are
shared.

Differential Revision: https://reviews.llvm.org/D84362
2020-09-16 17:35:28 -04:00
Johannes Doerfert 05fd04eda4 [OpenMP][FIX] Do not drop a '$' while demangling declare variant names
Reviewed By: ABataev

Differential Revision: https://reviews.llvm.org/D85876
2020-09-16 13:37:09 -05:00
Johannes Doerfert 6a02932bec [OpenMP][FIX] Do not crash trying to print a missing (demangled) user condition
Reviewed By: JonChesterfield

Differential Revision: https://reviews.llvm.org/D85875
2020-09-16 13:37:08 -05:00
Zequan Wu f975ae4867 [CodeGen][typeid] Emit typeinfo directly if type is known at compile-time
Differential Revision: https://reviews.llvm.org/D87425
2020-09-15 12:15:47 -07:00
Serge Pavlov f1cd6593da [AST][FPEnv] Keep FP options in trailing storage of CastExpr
This is recommit of 6c8041aa0f, reverted in de044f7562 because of some
fails. Original commit message is below.

This change allow a CastExpr to have optional FPOptionsOverride object,
stored in trailing storage. Of all cast nodes only ImplicitCastExpr,
CStyleCastExpr, CXXFunctionalCastExpr and CXXStaticCastExpr are allowed
to have FPOptions.

Differential Revision: https://reviews.llvm.org/D85960
2020-09-14 12:15:21 +07:00
Raphael Isemann c0bcd11068 [ASTImporter] Add basic support for comparing Stmts and compare function bodies
Right now the ASTImporter assumes for most Expr nodes that they are always equal
which leads to non-compatible declarations ending up being merged. This patch
adds the basic framework for comparing Stmts (and with that also Exprs) and
implements the custom checks for a few Stmt subclasses. I'll implement the
remaining subclasses in follow up patches (mostly because there are a lot of
subclasses and some of them require further changes like having GNU language in
the testing framework)

The motivation for this is that in LLDB we try to import libc++ source code and
some of the types we are importing there contain expressions (e.g. because they
use `enable_if<expr>`), so those declarations are currently merged even if they
are completely different (e.g. `enable_if<value> ...` and `enable_if<!value>
...` are currently considered equal which is clearly not true).

Reviewed By: martong, balazske

Differential Revision: https://reviews.llvm.org/D87444
2020-09-13 18:25:04 +02:00
Serge Pavlov de044f7562 Revert "[AST][FPEnv] Keep FP options in trailing storage of CastExpr"
This reverts commit 6c8041aa0f.
It caused some fails on buildbots.
2020-09-12 17:06:42 +07:00
Serge Pavlov 6c8041aa0f [AST][FPEnv] Keep FP options in trailing storage of CastExpr
This change allow a CastExpr to have optional FPOptionsOverride object,
stored in trailing storage. Of all cast nodes only ImplicitCastExpr,
CStyleCastExpr, CXXFunctionalCastExpr and CXXStaticCastExpr are allowed
to have FPOptions.

Differential Revision: https://reviews.llvm.org/D85960
2020-09-12 14:30:44 +07:00
Zequan Wu 83286a1a8f [MS ABI] Add mangled type for auto template parameter whose argument kind is Integeral 2020-09-11 16:19:43 -07:00
Cullen Rhodes cabd60c26b [clang][aarch64] Fix mangling of bfloat16 neon vectors
The AAPCS64 specifies the internal type is used for c++ mangling. For
bfloat16 it was defined as `BFloat16` when it should be `Bfloat16`, i.e.
lowercase 'f'.

For more information, see:

https://github.com/ARM-software/abi-aa/blob/master/aapcs64/aapcs64.rst#appendix-support-for-advanced-simd-extensions

Reviewed By: stuij

Differential Revision: https://reviews.llvm.org/D87463
2020-09-11 10:11:45 +00:00
Cullen Rhodes 002f5ab3b1 [clang][aarch64] Fix ILP32 ABI for arm_sve_vector_bits
The element types of scalable vectors are defined in terms of stdint
types in the ACLE. This patch fixes the mapping to builtin types for the
ILP32 ABI when creating VLS types with the arm_sve_vector_bits, where
the mapping is as follows:

  int32_t -> LongTy
  int64_t -> LongLongTy
  uint32_t -> UnsignedLongTy
  uint64_t -> UnsignedLongLongTy

This is implemented by leveraging getBuiltinVectorTypeInfo which is
target agnostic since it calls ASTContext::getIntTypeForBitwidth for
integer types. The element type for svfloat16_t is changed from
Float16Ty to HalfTy when creating VLS types since this is what is used
elsewhere.

For more information, see:

https://github.com/ARM-software/abi-aa/blob/master/aapcs64/aapcs64.rst#types-varying-by-data-model
https://github.com/ARM-software/abi-aa/blob/master/aapcs64/aapcs64.rst#appendix-support-for-scalable-vectors

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D87358
2020-09-11 09:46:35 +00:00
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
Eduardo Caldas c0e5e3fbfa [Ignore Expressions] Fix performance regression by inlining `Ignore*SingleStep`
We also add a `const` versions of `IgnoreExprNodes`

Differential Revision: https://reviews.llvm.org/D87278
2020-09-09 07:32:40 +00:00
Raphael Isemann 23f700c785 Revert "[clang] Prevent that Decl::dump on a CXXRecordDecl deserialises further declarations."
This reverts commit 0478720157. This probably
doesn't work when forcing deserialising while dumping (which the ASTDumper
optionally supports).
2020-09-07 14:50:13 +02:00
Raphael Isemann 0478720157 [clang] Prevent that Decl::dump on a CXXRecordDecl deserialises further declarations.
Decl::dump is primarily used for debugging to visualise the current state of a
declaration. Usually Decl::dump just displays the current state of the Decl and
doesn't actually change any of its state, however since commit
457226e02a the method actually started loading
additional declarations from the ExternalASTSource. This causes that calling
Decl::dump during a debugging session now actually does permanent changes to the
AST and will cause the debugged program run to deviate from the original run.

The change that caused this behaviour is the addition of
`hasConstexprDestructor` (which is called from the TextNodeDumper) which
performs a lookup into the current CXXRecordDecl to find the destructor. All
other similar methods just return their respective bit in the DefinitionData
(which obviously doesn't have such side effects).

This just changes the node printer to emit "unknown_constexpr" in case a
CXXRecordDecl is dumped that could potentially call into the ExternalASTSource
instead of the usually empty string/"constexpr". For CXXRecordDecls that can
safely be dumped the old behaviour is preserved

Reviewed By: bruno

Differential Revision: https://reviews.llvm.org/D80878
2020-09-07 12:31:30 +02:00
Eduardo Caldas 1a7a2cd747 [Ignore Expressions][NFC] Refactor to better use `IgnoreExpr.h` and nits
This change groups
* Rename: `ignoreParenBaseCasts` -> `IgnoreParenBaseCasts` for uniformity
* Rename: `IgnoreConversionOperator` -> `IgnoreConversionOperatorSingleStep` for uniformity
* Inline `IgnoreNoopCastsSingleStep` into a lambda inside `IgnoreNoopCasts`
* Refactor `IgnoreUnlessSpelledInSource` to make adequate use of `IgnoreExprNodes`

Differential Revision: https://reviews.llvm.org/D86880
2020-09-07 09:32:30 +00:00
Eduardo Caldas 81aa66f65f Extract infrastructure to ignore intermediate expressions into `clang/AST/IgnoreExpr.h`
Rationale:
This allows users to use `IgnoreExprNodes` and `Ignore*SingleStep` outside of
`clang/AST/Expr.cpp`.

Minor:
Rename `IgnoreImp...SingleStep`  into `IgnoreImplicit...SingleStep`.

Differential Revision: https://reviews.llvm.org/D86778
2020-09-07 09:32:30 +00:00
Benjamin Kramer 4d0312c8e0 Add proper move ctor/move assign to APValue. NFCI.
Swapping 64 bytes to make a move isn't cheap.
2020-09-06 13:02:11 +02:00
Nico Weber 7b0332389a Revert "Canonicalize declaration pointers when forming APValues."
This reverts commit e6393ee813.
It breaks Wunreachable for weak attributes, see
http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20200831/336645.html
2020-09-04 10:13:28 -04:00
Richard Smith e6393ee813 Canonicalize declaration pointers when forming APValues.
References to different declarations of the same entity aren't different
values, so shouldn't have different representations.
2020-09-03 15:35:12 -07:00
Erik Pilkington 9523cf02c2 [AST] Fix handling of long double and bool in __builtin_bit_cast
On x86, long double has 6 unused trailing bytes. This patch changes the
constant evaluator to treat them as though they were padding bytes, so reading
from them results in an indeterminate value, and nothing is written for them.
Also, fix a similar bug with bool, but instead of treating the unused bits as
padding, enforce that they're zero.

Differential revision: https://reviews.llvm.org/D76323
2020-09-02 15:01:53 -04:00
Erik Pilkington d46f2c51e4 Make -fvisibility-inlines-hidden apply to static local variables in inline functions on Darwin
This effectively disables r340386 on Darwin, and provides a command line flag
to opt into/out of this behaviour. This change is needed to compile certain
Apple headers correctly.

rdar://47688592

Differential revision: https://reviews.llvm.org/D86881
2020-09-02 12:19:12 -04:00
Cullen Rhodes 2ddf795e8c Reland "[CodeGen][AArch64] Support arm_sve_vector_bits attribute"
This relands D85743 with a fix for test
CodeGen/attr-arm-sve-vector-bits-call.c that disables the new pass
manager with '-fno-experimental-new-pass-manager'. Test was failing due
to IR differences with the new pass manager which broke the Fuchsia
builder [1]. Reverted in 2e7041f.

[1] http://lab.llvm.org:8011/builders/fuchsia-x86_64-linux/builds/10375

Original summary:

This patch implements codegen 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.

VLSTs are represented as VectorType in the AST and fixed-length vectors
in the IR everywhere except in function args/return. Implemented in this
patch is codegen support for the following:

  * Implicit casting between VLA <-> VLS types.
  * Coercion of VLS types in function args/return.
  * Mangling of VLS types.

Casting is handled by the CK_BitCast operation, which has been extended
to support the two new vector kinds for fixed-length SVE predicate and
data vectors, where the cast is implemented through memory rather than a
bitcast which is unsupported. Implementing this as a normal bitcast
would require relaxing checks in LLVM to allow bitcasting between
scalable and fixed types. Another option was adding target-specific
intrinsics, although codegen support would need to be added for these
intrinsics. Given this, casting through memory seemed like the best
approach as it's supported today and existing optimisations may remove
unnecessary loads/stores, although there is room for improvement here.

Coercion of VLSTs in function args/return from fixed to scalable is
implemented through the AArch64 ABI in TargetInfo.

The VLA and VLS types are defined by the ACLE to map to the same
machine-level SVE vectors. VLS types are mangled in the same way as:

  __SVE_VLS<typename, unsigned>

where the first argument is the underlying variable-length type and the
second argument is the SVE vector length in bits. For example:

  #if __ARM_FEATURE_SVE_BITS==512
  // Mangled as 9__SVE_VLSIu11__SVInt32_tLj512EE
  typedef svint32_t vec __attribute__((arm_sve_vector_bits(512)));
  // Mangled as 9__SVE_VLSIu10__SVBool_tLj512EE
  typedef svbool_t pred __attribute__((arm_sve_vector_bits(512)));
  #endif

The latest ACLE specification (00bet5) does not contain details of this
mangling scheme, it will be specified in the next revision.  The
mangling scheme is otherwise defined in the appendices to the Procedure
Call Standard for the Arm Architecture, see [2] for more information.

[1] https://developer.arm.com/documentation/100987/latest
[2] https://github.com/ARM-software/abi-aa/blob/master/aapcs64/aapcs64.rst#appendix-c-mangling

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D85743
2020-08-28 15:57:09 +00:00
Cullen Rhodes 2e7041fdc2 Revert "[CodeGen][AArch64] Support arm_sve_vector_bits attribute"
Test CodeGen/attr-arm-sve-vector-bits-call.c is failing on some builders
[1][2]. Reverting whilst I investigate.

[1] http://lab.llvm.org:8011/builders/fuchsia-x86_64-linux/builds/10375
[2] https://luci-milo.appspot.com/p/fuchsia/builders/ci/clang-linux-x64/b8870800848452818112

This reverts commit 42587345a3.
2020-08-27 21:31:05 +00:00
Cullen Rhodes 42587345a3 [CodeGen][AArch64] Support arm_sve_vector_bits attribute
This patch implements codegen 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.

VLSTs are represented as VectorType in the AST and fixed-length vectors
in the IR everywhere except in function args/return. Implemented in this
patch is codegen support for the following:

  * Implicit casting between VLA <-> VLS types.
  * Coercion of VLS types in function args/return.
  * Mangling of VLS types.

Casting is handled by the CK_BitCast operation, which has been extended
to support the two new vector kinds for fixed-length SVE predicate and
data vectors, where the cast is implemented through memory rather than a
bitcast which is unsupported. Implementing this as a normal bitcast
would require relaxing checks in LLVM to allow bitcasting between
scalable and fixed types. Another option was adding target-specific
intrinsics, although codegen support would need to be added for these
intrinsics. Given this, casting through memory seemed like the best
approach as it's supported today and existing optimisations may remove
unnecessary loads/stores, although there is room for improvement here.

Coercion of VLSTs in function args/return from fixed to scalable is
implemented through the AArch64 ABI in TargetInfo.

The VLA and VLS types are defined by the ACLE to map to the same
machine-level SVE vectors. VLS types are mangled in the same way as:

  __SVE_VLS<typename, unsigned>

where the first argument is the underlying variable-length type and the
second argument is the SVE vector length in bits. For example:

  #if __ARM_FEATURE_SVE_BITS==512
  // Mangled as 9__SVE_VLSIu11__SVInt32_tLj512EE
  typedef svint32_t vec __attribute__((arm_sve_vector_bits(512)));
  // Mangled as 9__SVE_VLSIu10__SVBool_tLj512EE
  typedef svbool_t pred __attribute__((arm_sve_vector_bits(512)));
  #endif

The latest ACLE specification (00bet5) does not contain details of this
mangling scheme, it will be specified in the next revision.  The
mangling scheme is otherwise defined in the appendices to the Procedure
Call Standard for the Arm Architecture, see [2] for more information.

[1] https://developer.arm.com/documentation/100987/latest
[2] https://github.com/ARM-software/abi-aa/blob/master/aapcs64/aapcs64.rst#appendix-c-mangling

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D85743
2020-08-27 15:11:58 +00:00
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
Adam Czachorowski eed0af6179 [clang] Exclude invalid destructors from lookups.
This fixes a crash when declaring a destructor with a wrong name, then
writing result to pch file and loading it again. The PCH storage uses
DeclarationNameKey as key and it is the same key for both the invalid
destructor and the implicit one that was created because the other one
was invalid. When querying for the Foo::~Foo we end up getting
Foo::~Bar, which is then rejected and we end up with nullptr in
CXXRecordDecl::GetDestructor().

Fixes https://bugs.llvm.org/show_bug.cgi?id=47270

Differential Revision: https://reviews.llvm.org/D86624
2020-08-26 19:29:30 +02:00