Commit Graph

16647 Commits

Author SHA1 Message Date
Vojislav Tomasevic
2a77d92e2e [clang] Incorrect IR involving the use of bcopy (#79298)
This patch addresses the issue regarding the call of bcopy function in a
conditional expression.
It is analogous to the already accepted patch which deals with the same
problem, just regarding the bzero function [0].

Here is the testcase which illustrates the issue:

```
void bcopy(const void *, void *, unsigned long);
void foo(void);

void test_bcopy() {
  char dst[20];
  char src[20];
  int _sz = 20, len = 20;
  return (_sz
          ? ((_sz >= len)
             ? bcopy(src, dst, len)
             : foo())
          : bcopy(src, dst, len));
}
```

When processing it with clang, following issue occurs:

Instruction does not dominate all uses!
%arraydecay2 = getelementptr inbounds [20 x i8], ptr %dst, i64 0, i64 0,
!dbg !38
%cond = phi ptr [ %arraydecay2, %cond.end ], [ %arraydecay5,
%cond.false3 ], !dbg !33
fatal error: error in backend: Broken module found, compilation aborted!

This happens because an incorrect phi node is created. It is created
because bcopy function call is lowered to the call of llvm.memmove
intrinsic and function memmove returns void *. Since llvm.memmove is
called in two places in the same return statement, clang creates a phi
node in the final basic block for the return value and that phi node is
incorrect. However, bcopy function should return void in the first
place, so this phi node is unnecessary. This is what this patch
addresses. An appropriate test is also added and no existing tests fail
when applying this patch.

Also, this crash only happens when LLVM is configured with
-DLLVM_ENABLE_ASSERTIONS=On option.

[0] https://reviews.llvm.org/D39746
2024-01-24 09:39:36 -08:00
Mirko Brkušanin
7fdf608cef [AMDGPU] Add GFX12 WMMA and SWMMAC instructions (#77795)
Co-authored-by: Petar Avramovic <Petar.Avramovic@amd.com>
Co-authored-by: Piotr Sobczak <piotr.sobczak@amd.com>
2024-01-24 13:43:07 +01:00
Paul Kirth
9d476e1e1a [clang][FatLTO] Avoid UnifiedLTO until it can support WPD/CFI (#79061)
Currently, the UnifiedLTO pipeline seems to have trouble with several
LTO features, like SplitLTO units, which means we cannot use important
optimizations like Whole Program Devirtualization or security hardening
instrumentation like CFI.

This patch reverts FatLTO to using distinct pipelines for Full LTO and
ThinLTO. It still avoids module cloning, since that was error prone.
2024-01-23 14:04:52 -08:00
Sander de Smalen
1652d44d8d [Clang] Amend SME attributes with support for ZT0. (#77941)
This patch builds on top of #76971 and implements support for:
* __arm_new("zt0")
* __arm_in("zt0")
* __arm_out("zt0")
* __arm_inout("zt0")
* __arm_preserves("zt0")
2024-01-23 12:35:16 +01:00
ManuelvOK
ce3e767ac5 [Coverage] Map regions from system headers (#76950)
In 2155195131, the
"system-headers-coverage" option has been added but not used in all
necessary places.

Potential reviewers: @gulfemsavrun @petrhosek

Co-authored-by: Manuel Kalettka <manuel.kalettka@kernkonzept.com>
2024-01-22 21:41:49 -08:00
Eli Friedman
a6065f0fa5 Arm64EC entry/exit thunks, consolidated. (#79067)
This combines the previously posted patches with some additional work
I've done to more closely match MSVC output.

Most of the important logic here is implemented in
AArch64Arm64ECCallLowering. The purpose of the
AArch64Arm64ECCallLowering is to take "normal" IR we'd generate for
other targets, and generate most of the Arm64EC-specific bits:
generating thunks, mangling symbols, generating aliases, and generating
the .hybmp$x table. This is all done late for a few reasons: to
consolidate the logic as much as possible, and to ensure the IR exposed
to optimization passes doesn't contain complex arm64ec-specific
constructs.

The other changes are supporting changes, to handle the new constructs
generated by that pass.

There's a global llvm.arm64ec.symbolmap representing the .hybmp$x
entries for the thunks. This gets handled directly by the AsmPrinter
because it needs symbol indexes that aren't available before that.

There are two new calling conventions used to represent calls to and
from thunks: ARM64EC_Thunk_X64 and ARM64EC_Thunk_Native. There are a few
changes to handle the associated exception-handling info,
SEH_SaveAnyRegQP and SEH_SaveAnyRegQPX.

I've intentionally left out handling for structs with small
non-power-of-two sizes, because that's easily separated out. The rest of
my current work is here. I squashed my current patches because they were
split in ways that didn't really make sense. Maybe I could split out
some bits, but it's hard to meaningfully test most of the parts
independently.

Thanks to @dpaoliello for extensive testing and suggestions.

(Originally posted as https://reviews.llvm.org/D157547 .)
2024-01-22 21:28:07 -08:00
Alan Phipps
424b9cf41a [Coverage][clang] Ensure bitmap for ternary condition is updated before visiting children (#78814)
This is a fix for MC/DC issue https://github.com/llvm/llvm-project/issues/78453 in which a ConditionalOperator that evaluates a complex condition was incorrectly updating its global bitmap after visiting its LHS and RHS children. This
was wrong because if the LHS or RHS also evaluate a complex condition, the MCDC temporary bitmap value will get corrupted. The fix is to ensure that the bitmap is updated prior to visiting the LHS and RHS.
2024-01-22 16:33:20 -06:00
Jan Patrick Lehr
fa4780fa6c [OpenMP][USM] Introduces -fopenmp-force-usm flag (#76571)
This flag forces the compiler to generate code for OpenMP target regions
as if the user specified the #pragma omp requires unified_shared_memory
in each source file.

The option does not have a -fno-* friend since OpenMP requires the
unified_shared_memory clause to be present in all source files. Since
this flag does no harm if the clause is present, it can be used in
conjunction. My understanding is that USM should not be turned off
selectively, hence, no -fno- version.

This adds a basic test to check the correct generation of double
indirect access to declare target globals in USM mode vs non-USM mode.
Which I think is the only difference observable in code generation.

This runtime test checks for the (non-)occurence of data movement between host
and device. It does one run without the flag and one with the flag to
also see that both versions behave as expected. In the case w/o the new
flag data movement between host and device is expected. In the case with
the flag such data movement should not be present / reported.
2024-01-22 21:59:26 +01:00
Zahira Ammarguellat
364a5b5b85 Fix a bug in implementation of Smith's algorithm used in complex div. (#78330)
This patch fixes a bug in Smith's algorithm (thanks to @andykaylor who
detected it) and makes sure that last option in command line rules.
2024-01-22 15:50:24 -05:00
Dani
1be0d9d7d8 [AArch64][Clang] Fix linker error for function multiversioning (#74358)
AArch64 part of https://github.com/llvm/llvm-project/pull/71706.

Default version is now mangled with .default.
Resolver for the TargetVersion need to be emitted from the
CodeGenModule::EmitMultiVersionFunctionDefinition.
2024-01-22 19:55:16 +01:00
Matthew Devereau
6ba62f4f25 [AArch64][SME2] Refine fcvtu/fcvts/scvtf/ucvtf (#77947)
Rename intrinsics for fcvtu to fcvtzu and fcvts to fcvtzs.

Use llvm_anyvector_ty for both multi vector returns and operands,
therefore the return and operands can be specified in the intrinsic
call, e.g.

@llvm.aarch64.sve.scvtf.x4.nxv4f32.nxv4i32
2024-01-22 15:11:49 +00:00
Hana Dusíková
865e4a1f33 [coverage] skipping code coverage for 'if constexpr' and 'if consteval' (#78033)
`if constexpr` and `if consteval` conditional statements code coverage
should behave more like a preprocesor `#if`-s than normal
ConditionalStmt. This PR should fix that.

---------

Co-authored-by: cor3ntin <corentinjabot@gmail.com>
2024-01-22 12:50:20 +01:00
David Chisnall
f36845d0c6 Enable direct methods and fast alloc calls for libobjc2. (#78030)
These will be supported in the upcoming 2.2 release and so are gated on
that version.

Direct methods call `objc_send_initialize` if they are class methods
that may not have called initialize. This is guarded by checking for the
class flag bit that is set on initialisation in the class. This bit now
forms part of the ABI, but it's been stable for 30+ years so that's fine
as a contract going forwards.
2024-01-22 08:38:41 +00:00
Andrey Ali Khan Bolshakov
5518a9d767 [c++20] P1907R1: Support for generalized non-type template arguments of scalar type. (#78041)
Previously committed as 9e08e51a20, and
reverted because a dependency commit was reverted, then committed again
as 4b574008ae and reverted again because
"dependency commit" 5a391d38ac was
reverted. But it doesn't seem that 5a391d38ac was a real dependency
for this.

This commit incorporates 4b574008ae and
18e093faf7 by Richard Smith (@zygoloid),
with some minor fixes, most notably:

- `UncommonValue` renamed to `StructuralValue`

- `VK_PRValue` instead of `VK_RValue` as default kind in lvalue and
member pointer handling branch in
`BuildExpressionFromNonTypeTemplateArgumentValue`;

- handling of `StructuralValue` in `IsTypeDeclaredInsideVisitor`;

- filling in `SugaredConverted` along with `CanonicalConverted`
parameter in `Sema::CheckTemplateArgument`;

- minor cleanup in
`TemplateInstantiator::transformNonTypeTemplateParmRef`;

- `TemplateArgument` constructors refactored;

- `ODRHash` calculation for `UncommonValue`;

- USR generation for `UncommonValue`;

- more correct MS compatibility mangling algorithm (tested on MSVC ver.
19.35; toolset ver. 143);

- IR emitting fixed on using a subobject as a template argument when the
corresponding template parameter is used in an lvalue context;

- `noundef` attribute and opaque pointers in `template-arguments` test;

- analysis for C++17 mode is turned off for templates in
`warn-bool-conversion` test; in C++17 and C++20 mode, array reference
used as a template argument of pointer type produces template argument
of UncommonValue type, and
`BuildExpressionFromNonTypeTemplateArgumentValue` makes
`OpaqueValueExpr` for it, and `DiagnoseAlwaysNonNullPointer` cannot see
through it; despite of "These cases should not warn" comment, I'm not
sure about correct behavior; I'd expect a suggestion to replace `if` by
`if constexpr`;

- `temp.arg.nontype/p1.cpp` and `dr18xx.cpp` tests fixed.
2024-01-21 21:28:57 +01:00
Kazu Hirata
9b2c25c704 [clang] Use SmallString::operator std::string (NFC) 2024-01-20 18:57:30 -08:00
bd1976bris
cd05ade13a Add a "don't override" mapping for -fvisibility-from-dllstorageclass (#74629)
`-fvisibility-from-dllstorageclass` allows for overriding the visibility
of globals from their DLL storage class. The visibility to apply can be
customised for the different classes of globals via a set of dependent
options that specify the mapping values:
- `-fvisibility-dllexport=<value>`
- `-fvisibility-nodllstorageclass=<value>`
- `-fvisibility-externs-dllimport=<value>`
- `-fvisibility-externs-nodllstorageclass=<value>` 

Currently, one of the existing LLVM visibilities, `hidden`, `protected`,
`default`, can be used as a mapping value. This change adds a new
mapping value: `keep`, which specifies that the visibility should not be
overridden for that class of globals. The behaviour of
`-fvisibility-from-dllstorageclass` is otherwise unchanged and existing
uses of this set of options will be unaffected.

The background to this change is that currently the PS4 and PS5
compilers effectively ignore visibility - dllimport/export is the
supported method for export control in C/C++ source code. Now, we would
like to support visibility attributes and options in our frontend, in
addition to dllimport/export. To support this, we will override the
visibility of globals with explicit dllimport/export annotations but use
the `keep` setting for globals which do not have an explicit
dllimport/export.

There are also some minor improvements to the existing options:
- Make the `LANGOPS` `BENIGN` as they don't involve the AST.
- Correct/clarify the help text for the options.
2024-01-19 21:57:40 +00:00
Haopeng Liu
a58ad3e2a3 [clang] Add size filter for stack auto init (#74777)
Add a clang flag, "-ftrivial-auto-var-init-max-size=" so that clang
skips auto-init a variable if the auto-init memset size exceeds the flag
setting (in bytes). Note that this skipping doesn't apply to
runtime-sized variables like VLA.

Considerations: "__attribute__((uninitialized))" can be used to manually
opt variables out. However, there are thousands of large variables
(e.g., >=1KB, most of them are arrays and used as buffers) in big
codebase. Manually opting them out one by one is not efficient.
2024-01-18 11:10:16 -08:00
Alan Zhao
2c9f04c98a [clang] Fix parenthesized list initialization of arrays not working with new (#76976)
This bug is caused by parenthesized list initialization not being
implemented in `CodeGenFunction::EmitNewArrayInitializer(...)`.

Parenthesized list initialization of `struct`s with `operator new`
already works in Clang and is not affected by this bug.

Additionally, fix the test new-delete.cpp as it incorrectly assumes that
using parentheses with operator new to initialize arrays is illegal for
C++ versions >= C++17.

Fixes #68198
2024-01-18 10:53:54 -08:00
Alan Phipps
22867890e4 [clang][CoverageMapping] Refactor setting MC/DC True/False Condition IDs (#78202)
Clean-up of the algorithm that assigns MC/DC True/False control-flow
condition IDs when constructing an MC/DC decision region. This patch
creates a common API for setting/getting the condition IDs, making the
binary logical operator visitor functions much cleaner.

This patch also fixes issue
https://github.com/llvm/llvm-project/issues/77873 in which a record's
control flow map can be malformed due to an incorrect calculation of the
True/False condition IDs.
2024-01-18 09:34:52 -06:00
cor3ntin
e90e43fb9c [Clang][NFC] Rename CXXMethodDecl::isPure -> is VirtualPure (#78463)
To avoid any possible confusion with the notion of pure function and the
gnu::pure attribute.
2024-01-18 15:30:58 +01:00
Piotr Sobczak
57f6a3f7ea [AMDGPU] Add global_load_tr for GFX12 (#77772)
Support new amdgcn_global_load_tr instructions for load with transpose.

* MC layer support for GLOBAL_LOAD_TR_B64/GLOBAL_LOAD_TR_B128
* Intrinsic int_amdgcn_global_load_tr
* Clang builtins amdgcn_global_load_tr*
2024-01-18 15:14:42 +01:00
Jonas Devlieghere
a4fe6a1838 [clang] Upstream XROS support in Clang (#78392)
Upstream XROS support in the clang frontend and driver.
2024-01-17 21:09:15 -08:00
Mikael Holmen
e6bd9835d9 [clang][CodeGen] Fix gcc warning about unused variable [NFC]
Without the fix gcc warned with
 ../../clang/lib/CodeGen/CGBuiltin.cpp:1022:19: warning: unused variable 'DRE' [-Wunused-variable]
  1022 |   if (const auto *DRE = dyn_cast<DeclRefExpr>(Base)) {
       |                   ^~~

Fix the warning by removing the unused variable and change the "dyn_cast"
to "isa".
2024-01-17 13:23:08 +01:00
Phoebe Wang
8d6e82d501 [X86] Use vXi1 for k constraint in inline asm (#77733)
Fixes #77172
2024-01-17 11:40:32 +08:00
Bill Wendling
00b6d032a2 [Clang] Implement the 'counted_by' attribute (#76348)
The 'counted_by' attribute is used on flexible array members. The
argument for the attribute is the name of the field member holding the
count of elements in the flexible array. This information is used to
improve the results of the array bound sanitizer and the
'__builtin_dynamic_object_size' builtin. The 'count' field member must
be within the same non-anonymous, enclosing struct as the flexible array
member. For example:

```
  struct bar;
  struct foo {
    int count;
    struct inner {
      struct {
        int count; /* The 'count' referenced by 'counted_by' */
      };
      struct {
        /* ... */
        struct bar *array[] __attribute__((counted_by(count)));
      };
    } baz;
  };
```

This example specifies that the flexible array member 'array' has the
number of elements allocated for it in 'count':

```
  struct bar;
  struct foo {
    size_t count;
     /* ... */
    struct bar *array[] __attribute__((counted_by(count)));
  };
```

This establishes a relationship between 'array' and 'count';
specifically that 'p->array' must have *at least* 'p->count' number of
elements available. It's the user's responsibility to ensure that this
relationship is maintained throughout changes to the structure.

In the following, the allocated array erroneously has fewer elements
than what's specified by 'p->count'. This would result in an
out-of-bounds access not not being detected:

```
  struct foo *p;

  void foo_alloc(size_t count) {
    p = malloc(MAX(sizeof(struct foo),
                   offsetof(struct foo, array[0]) + count *
                       sizeof(struct bar *)));
    p->count = count + 42;
  }
```

The next example updates 'p->count', breaking the relationship
requirement that 'p->array' must have at least 'p->count' number of
elements available:

```
  void use_foo(int index, int val) {
    p->count += 42;
    p->array[index] = val; /* The sanitizer can't properly check this access */
  }
```

In this example, an update to 'p->count' maintains the relationship
requirement:

```
  void use_foo(int index, int val) {
    if (p->count == 0)
      return;
    --p->count;
    p->array[index] = val;
  }
```
2024-01-16 14:26:12 -08:00
Craig Topper
142f270c27 Recommit "[AST] Use APIntStorage to fix memory leak in EnumConstantDecl. (#78311)"
With lldb build fix.

Original message:

EnumConstantDecl is allocated by the ASTContext allocator so the
destructor is never called.

This patch takes a similar approach to IntegerLiteral by using
APIntStorage to allocate large APSInts using the ASTContext allocator as
well.

The downside is that an additional heap allocation and copy of the data
needs to be made when calling getInitValue if the APSInt is large.

Fixes #78160.
2024-01-16 13:52:17 -08:00
Craig Topper
f3d534c425 Revert "[AST] Use APIntStorage to fix memory leak in EnumConstantDecl. (#78311)"
This reverts commit 4737959d91.

Missed an lldb update.
2024-01-16 12:39:47 -08:00
Craig Topper
4737959d91 [AST] Use APIntStorage to fix memory leak in EnumConstantDecl. (#78311)
EnumConstantDecl is allocated by the ASTContext allocator so the
destructor is never called.

This patch takes a similar approach to IntegerLiteral by using
APIntStorage to allocate large APSInts using the ASTContext allocator as
well.

The downside is that an additional heap allocation and copy of the data
needs to be made when calling getInitValue if the APSInt is large.

Fixes #78160.
2024-01-16 12:10:38 -08:00
Wang Pengcheng
3ac9fe69f7 [RISCV] CodeGen of RVE and ilp32e/lp64e ABIs (#76777)
This commit includes the necessary changes to clang and LLVM to support
codegen of `RVE` and the `ilp32e`/`lp64e` ABIs.

The differences between `RVE` and `RVI` are:
* `RVE` reduces the integer register count to 16(x0-x16).
* The ABI should be `ilp32e` for 32 bits and `lp64e` for 64 bits.

`RVE` can be combined with all current standard extensions.

The central changes in ilp32e/lp64e ABI, compared to ilp32/lp64 are:
* Only 6 integer argument registers (rather than 8).
* Only 2 callee-saved registers (rather than 12).
* A Stack Alignment of 32bits (rather than 128bits).
* ilp32e isn't compatible with D ISA extension.

If `ilp32e` or `lp64` is used with an ISA that has any of the registers
x16-x31 and f0-f31, then these registers are considered temporaries.

To be compatible with the implementation of ilp32e in GCC, we don't use
aligned registers to pass variadic arguments and set stack alignment\
to 4-bytes for types with length of 2*XLEN.

FastCC is also supported on RVE, while GHC isn't since there is only one
avaiable register.

Differential Revision: https://reviews.llvm.org/D70401
2024-01-16 20:44:30 +08:00
Rashmi Mudduluru
a511c1a9ec Revert "[Clang] Implement the 'counted_by' attribute (#76348)"
This reverts commit 164f85db87.
2024-01-15 18:37:52 -08:00
Yusra Syeda
d85df3f2d6 [SystemZ][z/OS] Add support for recognizing z/OS personality function in Clang (#76073)
This PR adds support makes Clang aware of the name of the personality
function on z/OS.

Co-authored-by: Yusra Syeda <yusra.syeda@ibm.com>
2024-01-15 10:18:07 -05:00
Sander de Smalen
8e7f073eb4 [Clang][AArch64] Change SME attributes for shared/new/preserved state. (#76971)
This patch replaces the `__arm_new_za`, `__arm_shared_za` and
`__arm_preserves_za` attributes in favour of:
* `__arm_new("za")`
* `__arm_in("za")`
* `__arm_out("za")`
* `__arm_inout("za")`
* `__arm_preserves("za")`

As described in https://github.com/ARM-software/acle/pull/276.

One change is that `__arm_in/out/inout/preserves(S)` are all mutually
exclusive, whereas previously it was fine to write `__arm_shared_za
__arm_preserves_za`. This case is now represented with `__arm_in("za")`.

The current implementation uses the same LLVM attributes under the hood,
since `__arm_in/out/inout` are all variations of "shared ZA", so can use
the existing `aarch64_pstate_za_shared` attribute in LLVM.

#77941 will add support for the new "zt0" state as introduced
with SME2.
2024-01-15 09:41:32 +00:00
Kazu Hirata
6bd488dd24 [CodeGen] Use DenseMap::contains (NFC) 2024-01-12 22:08:28 -08:00
Arthur Eubanks
f05b081214 [clang] Adjust -mlarge-data-threshold handling (#77958)
Make it apply to x86-64 medium and large code models since that's what
the backend does.

Limit logic to exclude x86-32.

Default to 0, let the driver set it to 65536 for the medium code model
if one is not passed. Set it to 0 for the large code model by default to
match gcc and since some users make assumptions about the large code
model that any small data will break.
2024-01-12 12:23:42 -08:00
Frederik Carlier
3168192de5 [ObjC]: Make type encoding safe in symbol names (#77797)
Type encodings are part of symbol names in the Objective C ABI. Replace
characters which are reseved in symbol names:

- ELF: avoid including '@' characters in type encodings
- Windows: avoid including '=' characters in type encodings
2024-01-12 09:03:37 +00:00
John Brawn
40d5c2bcd4 [clang][AArch64] Add a -mbranch-protection option to enable GCS (#75486)
-mbranch-protection=gcs (enabled by -mbranch-protection=standard) causes
generated objects to be marked with the gcs feature. This is done via
the guarded-control-stack module flag, in a similar way to
branch-target-enforcement and sign-return-address.

Enabling GCS causes the GNU_PROPERTY_AARCH64_FEATURE_1_GCS bit to be set
on generated objects. No code generation changes are required, as GCS
just requires that functions are called using BL and returned from using
RET (or other similar variant instructions), which is already the case.
2024-01-11 12:53:23 +00:00
Nikita Popov
158d72d728 [Clang] Set writable and dead_on_unwind attributes on sret arguments (#77116)
Set the writable and dead_on_unwind attributes for sret arguments. These
indicate that the argument points to writable memory (and it's legal to
introduce spurious writes to it on entry to the function) and that the
argument memory will not be used if the call unwinds.

This enables additional MemCpyOpt/DSE/LICM optimizations.
2024-01-11 09:46:54 +01:00
Bill Wendling
164f85db87 [Clang] Implement the 'counted_by' attribute (#76348)
The 'counted_by' attribute is used on flexible array members. The
argument for the attribute is the name of the field member holding the
count of elements in the flexible array. This information is used to
improve the results of the array bound sanitizer and the
'__builtin_dynamic_object_size' builtin. The 'count' field member must
be within the same non-anonymous, enclosing struct as the flexible array
member. For example:

```
  struct bar;
  struct foo {
    int count;
    struct inner {
      struct {
        int count; /* The 'count' referenced by 'counted_by' */
      };
      struct {
        /* ... */
        struct bar *array[] __attribute__((counted_by(count)));
      };
    } baz;
  };
```

This example specifies that the flexible array member 'array' has the
number of elements allocated for it in 'count':

```
  struct bar;
  struct foo {
    size_t count;
     /* ... */
    struct bar *array[] __attribute__((counted_by(count)));
  };
```

This establishes a relationship between 'array' and 'count';
specifically that 'p->array' must have *at least* 'p->count' number of
elements available. It's the user's responsibility to ensure that this
relationship is maintained throughout changes to the structure.

In the following, the allocated array erroneously has fewer elements
than what's specified by 'p->count'. This would result in an
out-of-bounds access not not being detected:

```
  struct foo *p;

  void foo_alloc(size_t count) {
    p = malloc(MAX(sizeof(struct foo),
                   offsetof(struct foo, array[0]) + count *
                       sizeof(struct bar *)));
    p->count = count + 42;
  }
```

The next example updates 'p->count', breaking the relationship
requirement that 'p->array' must have at least 'p->count' number of
elements available:

```
  void use_foo(int index, int val) {
    p->count += 42;
    p->array[index] = val; /* The sanitizer can't properly check this access */
  }
```

In this example, an update to 'p->count' maintains the relationship
requirement:

```
  void use_foo(int index, int val) {
    if (p->count == 0)
      return;
    --p->count;
    p->array[index] = val;
  }
```
2024-01-10 22:20:31 -08:00
Nico Weber
2dce77201c Revert "[Clang] Implement the 'counted_by' attribute (#76348)"
This reverts commit fefdef808c.

Breaks check-clang, see
https://github.com/llvm/llvm-project/pull/76348#issuecomment-1886029515

Also revert follow-on "[Clang] Update 'counted_by' documentation"

This reverts commit 4a3fb9ce27.
2024-01-10 21:05:19 -05:00
Bill Wendling
4a3fb9ce27 [Clang] Update 'counted_by' documentation
Describe a limitation of the 'counted_by' attribute when used in unions.
Also fix a errant typo.
2024-01-10 15:36:33 -08:00
Bill Wendling
fefdef808c [Clang] Implement the 'counted_by' attribute (#76348)
The 'counted_by' attribute is used on flexible array members. The
argument for the attribute is the name of the field member holding the
count of elements in the flexible array. This information is used to
improve the results of the array bound sanitizer and the
'__builtin_dynamic_object_size' builtin. The 'count' field member must
be within the same non-anonymous, enclosing struct as the flexible array
member. For example:

```
  struct bar;
  struct foo {
    int count;
    struct inner {
      struct {
        int count; /* The 'count' referenced by 'counted_by' */
      };
      struct {
        /* ... */
        struct bar *array[] __attribute__((counted_by(count)));
      };
    } baz;
  };
```

This example specifies that the flexible array member 'array' has the
number of elements allocated for it in 'count':

```
  struct bar;
  struct foo {
    size_t count;
     /* ... */
    struct bar *array[] __attribute__((counted_by(count)));
  };
```

This establishes a relationship between 'array' and 'count';
specifically that 'p->array' must have *at least* 'p->count' number of
elements available. It's the user's responsibility to ensure that this
relationship is maintained throughout changes to the structure.

In the following, the allocated array erroneously has fewer elements
than what's specified by 'p->count'. This would result in an
out-of-bounds access not not being detected:

```
  struct foo *p;

  void foo_alloc(size_t count) {
    p = malloc(MAX(sizeof(struct foo),
                   offsetof(struct foo, array[0]) + count *
                       sizeof(struct bar *)));
    p->count = count + 42;
  }
```

The next example updates 'p->count', breaking the relationship
requirement that 'p->array' must have at least 'p->count' number of
elements available:

```
  void use_foo(int index, int val) {
    p->count += 42;
    p->array[index] = val; /* The sanitizer can't properly check this access */
  }
```

In this example, an update to 'p->count' maintains the relationship
requirement:

```
  void use_foo(int index, int val) {
    if (p->count == 0)
      return;
    --p->count;
    p->array[index] = val;
  }
```
2024-01-10 15:21:10 -08:00
CarolineConcatto
14e7dac92a [Clang][LLVM][AArch64]SVE2.1 update the intrinsics according to acle[1] (#76844)
This patch changes the following intrinsic

 ```svst1uwq[_{d}]  replaced by svst1wq[_{d}]
 svst1uwq_vnum[_{d}] replaced by svst1wq_vnum[_{d}]
 svst1udq[_{d}]  replaced by svst1dq[_{d}]
 svst1udq_vnum[_{d}] replaced by svst1dq_vnum[_{d}]
```
Drops 'u' from the quadword stores because it is simply truncating the
quadwords to 32 bits

```
 svextq_lane[_{d}] replaced by  svextq[_{d}]
```
EXTQ follows the previous defined EXT intrinsics

```
 svdot[_{d}_{2}_{3}] replaced by svdot[_{d}_{2}]
```
Introduced with the latest SME2 ACLE change

[1]https://github.com/ARM-software/acle/pull/257
2024-01-10 17:12:14 +00:00
Frederik Carlier
1d5106d69c Objective C: use C++ exceptions on MinGW+GNUstep (#77255)
The GNUstep Objective C runtime (libobjc2) is adding support for the GNU
ABI on Windows (more specifically, MinGW). The libobjc2 runtime uses C++
exceptions in that configuration; this PR updates clang to act
accordingly.

The corresponding change to libobjc2 is here:
https://github.com/gnustep/libobjc2/pull/267
2024-01-10 16:52:13 +00:00
Hana Dusíková
a26cc759ae [clang][coverage] Fix "if constexpr" and "if consteval" coverage report (#77214)
Replace the discarded statement by an empty compound statement so we can keep track of the
whole source range we need to skip in coverage

Fixes #54419
2024-01-10 11:01:23 +01:00
Frederik Carlier
b81ba52e15 Set dllstorage on ObjectiveC ivar offsets (#77385)
Mark instance variable offset symbols with `dllexport`/`dllimport` if
they are not hidden and the interface declaration is marked with
`dllexport`/`dllimport`, when using the GNUstep 2.x ABI.

/cc @davidchisnall
2024-01-09 09:15:01 +00:00
hev
4df5662907 [clang] Add per-global code model attribute (#72078)
This patch adds a per-global code model attribute, which can override
the target's code model to access global variables.

Currently, the code model attribute is only supported on LoongArch. This
patch also maps GCC's code model names to LLVM's, which allows for
better compatibility between the two compilers.


Suggested-by: Arthur Eubanks <aeubanks@google.com>
Link:
https://discourse.llvm.org/t/how-to-best-implement-code-model-overriding-for-certain-values/71816
Link:
https://discourse.llvm.org/t/rfc-add-per-global-code-model-attribute/74944

---------

Signed-off-by: WANG Rui <wangrui@loongson.cn>
2024-01-06 08:51:59 +08:00
Phoebe Wang
f07aba4bc1 [X86] Add ABI handling for __float128 to match with GCC (#75156)
Fixes #74601
2024-01-05 21:53:47 +08:00
Alan Phipps
8b2bdfbca7 [Coverage][clang] Enable MC/DC Support in LLVM Source-based Code Coverage (3/3)
Part 3 of 3. This includes the MC/DC clang front-end components.

Differential Revision: https://reviews.llvm.org/D138849
2024-01-04 12:29:18 -06:00
Jannik Silvanus
7954c57124 [IR] Fix GEP offset computations for vector GEPs (#75448)
Vectors are always bit-packed and don't respect the elements' alignment
requirements. This is different from arrays. This means offsets of
vector GEPs need to be computed differently than offsets of array GEPs.

This PR fixes many places that rely on an incorrect pattern
that always relies on `DL.getTypeAllocSize(GTI.getIndexedType())`.
We replace these by usages of  `GTI.getSequentialElementStride(DL)`, 
which is a new helper function added in this PR.

This changes behavior for GEPs into vectors with element types for which
the (bit) size and alloc size is different. This includes two cases:

* Types with a bit size that is not a multiple of a byte, e.g. i1.
GEPs into such vectors are questionable to begin with, as some elements
  are not even addressable.
* Overaligned types, e.g. i16 with 32-bit alignment.

Existing tests are unaffected, but a miscompilation of a new test is fixed.

---------

Co-authored-by: Nikita Popov <github@npopov.com>
2024-01-04 10:08:21 +01:00
SunilKuravinakop
49ee8b53ef [OpenMP] atomic compare fail : Codegen support (#75709)
This is a continuation of https://reviews.llvm.org/D123235 ([OpenMP]
atomic compare fail : Parser & AST support). In this branch Support for
codegen support for atomic compare fail is being added.

---------

Co-authored-by: Sunil Kuravinakop
2024-01-02 22:46:02 +05:30