By both AAPCS32 and AAPCS64, the test for whether an aggregate
qualifies as homogeneous (either HFA or HVA) is based on the data
layout alone. So any logical member of the structure that does not
affect the data layout also should not affect homogeneity. In
particular, an empty bitfield ('int : 0') should make no difference.
In fact, clang considered it to make a difference in C but not in C++,
and justified that policy as compatible with gcc. But that's
considered a bug in gcc as well (at least for Arm targets), and it's
fixed in gcc 12.1.
This fix mimics gcc's: zero-sized bitfields are now ignored in all
languages for the Arm (32- and 64-bit) ABIs. But I've left the
previous behaviour unchanged in other ABIs, by means of adding an
ABIInfo::isZeroLengthBitfieldPermittedInHomogeneousAggregate query
method which the Arm subclasses override.
Reviewed By: lenary
Differential Revision: https://reviews.llvm.org/D127197
We are lacking builtins support for `_Float16`. In most cases, we can use other floating-type builtins and truncate them to `_Float16`.
But it's a problem to SNaN, e.g., https://gcc.godbolt.org/z/cqr5nG1jh
This patch adds `__builtin_nansf16` support as well as other 3 ones since they are usually used together.
Reviewed By: LuoYuanke
Differential Revision: https://reviews.llvm.org/D127050
A variable with `weak` attribute signifies that it can be replaced with
a "strong" symbol link time. Therefore it must not emitted with
"weak_odr" linkage, as that allows the backend to use its value in
optimizations.
The frontend already considers weak const variables as
non-constant (note_constexpr_var_init_weak diagnostic) so this change
makes frontend and backend consistent.
This commit reverses the
f49573d1 weak globals that are const should get weak_odr linkage.
commit from 2009-08-05 which introduced this behavior. Unfortunately
that commit doesn't provide any details on why the change was made.
This was discussed in
https://discourse.llvm.org/t/weak-attribute-semantics-on-const-variables/62311
Differential Revision: https://reviews.llvm.org/D126324
A bit of historical research shows that over the years:
Commit 99efc036 added `pragma comment lib` support for PS4.
Commit fd4db533 added `pragma comment lib` support for all ELF targets.
Commit 1d16515f reworked dependent-library support for all ELF targets.
The upshot is that some PS4-specific code became dead, and the
testing became somewhat fragmented. I've removed the dead code and
combined the previous PS4-specific and linux-specific tests for the
diagnostics into one generic ELF test.
Also added a couple of PS5 runs while I was in there.
This caused assertions, see comment on the code review:
llvm/clang/lib/AST/Decl.cpp:1510:
clang::LinkageInfo clang::LinkageComputer::getLVForDecl(const clang::NamedDecl *, clang::LVComputationKind):
Assertion `D->getCachedLinkage() == LV.getLinkage()' failed.
> The option mdefault-visibility-export-mapping is created to allow
> mapping default visibility to an explicit shared library export
> (e.g. dllexport). Exactly how and if this is manifested is target
> dependent (since it depends on how they map dllexport in the IR).
>
> Three values are provided for the option:
>
> * none: the default and behavior without the option, no additional export linkage information is created.
> * explicit: add the export for entities with explict default visibility from the source, including RTTI
> * all: add the export for all entities with default visibility
>
> This option is useful for targets which do not export symbols as part of
> their usual default linkage behaviour (e.g. AIX), such targets
> traditionally specified such information in external files (e.g. export
> lists), but this mapping allows them to use the visibility information
> typically used for this purpose on other (e.g. ELF) platforms.
>
> Reviewed By: MaskRay
>
> Differential Revision: https://reviews.llvm.org/D126340
This reverts commit 8c8a2679a20f621994fa904bcfc68775e7345edc.
This reverts commit d374b65f2da1bdd3d9a7e9ac8ed4ad5467c882f9.
The changes lose AST fidelity (reported in #55778), but also may be
improperly dropping _Atomic qualifiers. I am rolling the changes back
until I've finished discussions in WG14 about the proper resolution to
DR423.
This enabled opaque pointers by default in LLVM. The effect of this
is twofold:
* If IR that contains *neither* explicit ptr nor %T* types is passed
to tools, we will now use opaque pointer mode, unless
-opaque-pointers=0 has been explicitly passed.
* Users of LLVM as a library will now default to opaque pointers.
It is possible to opt-out by calling setOpaquePointers(false) on
LLVMContext.
A cmake option to toggle this default will not be provided. Frontends
or other tools that want to (temporarily) keep using typed pointers
should disable opaque pointers via LLVMContext.
Differential Revision: https://reviews.llvm.org/D126689
LTO code may end up mixing bitcode files from various sources varying in
their use of opaque pointer types. The current strategy to decide
between opaque / typed pointers upon the first bitcode file loaded does
not work here, since we could be loading a non-opaque bitcode file first
and would then be unable to load any files with opaque pointer types
later.
So for LTO this:
- Adds an `lto::Config::OpaquePointer` option and enforces an upfront
decision between the two modes.
- Adds `-opaque-pointers`/`-no-opaque-pointers` options to the gold
plugin; disabled by default.
- `--opaque-pointers`/`--no-opaque-pointers` options with
`-plugin-opt=-opaque-pointers`/`-plugin-opt=-no-opaque-pointers`
aliases to lld; disabled by default.
- Adds an `-lto-opaque-pointers` option to the `llvm-lto2` tool.
- Changes the clang driver to pass `-plugin-opt=-opaque-pointers` to
the linker in LTO modes when clang was configured with opaque
pointers enabled by default.
This fixes https://github.com/llvm/llvm-project/issues/55377
Differential Revision: https://reviews.llvm.org/D125847
The option mdefault-visibility-export-mapping is created to allow
mapping default visibility to an explicit shared library export
(e.g. dllexport). Exactly how and if this is manifested is target
dependent (since it depends on how they map dllexport in the IR).
Three values are provided for the option:
* none: the default and behavior without the option, no additional export linkage information is created.
* explicit: add the export for entities with explict default visibility from the source, including RTTI
* all: add the export for all entities with default visibility
This option is useful for targets which do not export symbols as part of
their usual default linkage behaviour (e.g. AIX), such targets
traditionally specified such information in external files (e.g. export
lists), but this mapping allows them to use the visibility information
typically used for this purpose on other (e.g. ELF) platforms.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D126340
For some reason, we implemented the xx_stxvp intrinsics
to require a const pointer. This absolutely doesn't make
sense for a store. Remove the const from the definition.
Post-commit feedback on https://reviews.llvm.org/D122895 pointed out
that the diagnostic wording for some code was using "declaration" in a
confusing way, such as:
int foo(); // warning: a function declaration without a prototype is deprecated in all versions of C and is not supported in C2x
int foo(int arg) { // warning: a function declaration without a prototype is deprecated in all versions of C and is not supported in C2x
return 5;
}
And that we had other minor issues with the diagnostics being somewhat
confusing.
This patch addresses the confusion by reworking the implementation to
be a bit more simple and a bit less chatty. Specifically, it changes
the warning and note diagnostics to be able to specify "declaration" or
"definition" as appropriate, and it changes the function merging logic
so that the function without a prototype is always what gets warned on,
and the function with a prototype is sometimes what gets noted.
Additionally, when diagnosing a K&R C definition that is preceded by a
function without a prototype, we don't note the prior declaration, we
warn on it because it will also be changing behavior in C2x.
Differential Revision: https://reviews.llvm.org/D125814
https://docs.microsoft.com/en-us/cpp/intrinsics/arm64-intrinsics?view=msvc-170
unsigned char __readx18byte(unsigned long)
unsigned short __readx18word(unsigned long)
unsigned long __readx18dword(unsigned long)
unsigned __int64 __readx18qword(unsigned long)
Given the lack of documentation of the intrinsics, we chose to align the offset with just
`CharUnits::One()` when calling `IRBuilderBase::CreateAlignedLoad()`
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D126024
https://docs.microsoft.com/en-us/cpp/intrinsics/arm64-intrinsics?view=msvc-170
void __writex18byte(unsigned long, unsigned char)
void __writex18word(unsigned long, unsigned short)
void __writex18dword(unsigned long, unsigned long)
void __writex18qword(unsigned long, unsigned __int64)
Given the lack of documentation of the intrinsics, we chose to align the offset with just
`CharUnits::One()` when calling `IRBuilderBase::CreateAlignedStore()`.
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D126023
Support for `__attribute__((no_builtin("foo")))` was added in https://reviews.llvm.org/D68028,
but builtins were still being used even when the attribute was placed on a function.
Reviewed By: hans
Differential Revision: https://reviews.llvm.org/D124701
WG14 DR423 (https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2148.htm#dr_423),
resolved during the C11 time frame, changed the way qualifiers are
handled on function return types and in cast expressions after it was
noted that these types are now directly observable via generic
selection expressions. In C, the function declarator is adjusted to
ignore all qualifiers (including _Atomic qualifiers).
Clang already handles the cast expression case correctly (by performing
the lvalue conversion, which drops the qualifiers as well), but with
these changes it will now also handle function declarations
appropriately.
Fixes#39595
Differential Revision: https://reviews.llvm.org/D125919
It doesn't matter which value we use for dead args, so let's switch
to poison, so we can eventually kill undef.
Reviewed By: aeubanks, fhahn
Differential Revision: https://reviews.llvm.org/D125983
This patch implements the following floating point negative absolute value
builtins that required for compatibility with the XL compiler:
```
double __fnabs(double);
float __fnabss(float);
```
These builtins will emit :
- fnabs on PWR6 and below, or if VSX is disabled.
- xsnabsdp on PWR7 and above, if VSX is enabled.
Differential Revision: https://reviews.llvm.org/D125506
An upcoming patch will extend llvm-symbolizer to provide the source line
information for global variables. The goal is to move AddressSanitizer
off of internal debug info for symbolization onto the DWARF standard
(and doing a clean-up in the process). Currently, ASan reports the line
information for constant strings if a memory safety bug happens around
them. We want to keep this behaviour, so we need to emit debuginfo for
these variables as well.
Reviewed By: dblaikie, rnk, aprantl
Differential Revision: https://reviews.llvm.org/D123534
CSKY is always in 4-byte align, no matter it's long long type.
For global aggregate variable, it's 4-byte align if its size is bigger than or equal to 4 bytes.
Differential Revision: https://reviews.llvm.org/D124977
Similar to D123386, this adds D-Movs to the AArch64 perfect shuffle
tables, slightly lowering the costs a little more. This is a rough
improvement in general, especially if you ignore mov v0.16b, v2.16b type
moves that are often artefacts of the calling convention.
The D register movs are encoded as (0x4 | LaneIdx), and to generate a D
register move we are required to bitcast into a higher type, but it is
otherwise very similar to the S-lane mov's already supported.
Differential Revision: https://reviews.llvm.org/D125477
This reverts commit 4680982b36a84770a1600fc438be8ec090671724.
Broke a fuchsia windows bot. More details in the review:
https://reviews.llvm.org/D123534
An upcoming patch will extend llvm-symbolizer to provide the source line
information for global variables. The goal is to move AddressSanitizer
off of internal debug info for symbolization onto the DWARF standard
(and doing a clean-up in the process). Currently, ASan reports the line
information for constant strings if a memory safety bug happens around
them. We want to keep this behaviour, so we need to emit debuginfo for
these variables as well.
Reviewed By: dblaikie, rnk, aprantl
Differential Revision: https://reviews.llvm.org/D123534
The goal is support tail and mask policy in RVV builtins.
We focus on IR part first.
If the passthru operand is undef, we use tail agnostic, otherwise
use tail undisturbed.
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D125323
The re-apply includes fixes to clang tests that were missed in
the original commit.
Original message:
Prior to this patch we would only set to undef the unused arguments of the
external functions. The rationale was that unused arguments of internal
functions wouldn't need to be turned into undef arguments because they
should have been simply eliminated by the time we reach that code.
This is actually not true because there are plenty of cases where we can't
remove unused arguments. For instance, if the internal function is used in
an indirect call, it may not be possible to change the function signature.
Yet, for statically known call-sites we would still like to mark the unused
arguments as undef.
This patch enables the "set undef arguments" optimization on internal
functions when we encounter cases where internal functions cannot be
optimized. I.e., whenever an internal function is marked "live".
Differential Revision: https://reviews.llvm.org/D124699
D87451 added -mignore-xcoff-visibility for AIX targets and made it the default (which mimicked the behaviour of the XL 16.1 compiler on AIX).
However, ignoring hidden visibility has unwanted side effects and some libraries depend on visibility to hide non-ABI facing entities from user headers and
reserve the right to change these implementation details based on this (https://libcxx.llvm.org/DesignDocs/VisibilityMacros.html). This forces us to use
internal linkage fallbacks for these cases on AIX and creates an unwanted divergence in implementations on the plaform.
For these reasons, it's preferable to not add -mignore-xcoff-visibility by default, which is what this patch does.
Reviewed By: DiggerLin
Differential Revision: https://reviews.llvm.org/D125141
Currently for SVE2 ACLE builtins, single tests are used to verify both
clang code generation (when the feature is available) and semantic
error/warning messages (when the feature is unavailable). This
patch moves the semantic testing for the target feature flag into
dedicated Sema tests.
Differential Revision: https://reviews.llvm.org/D124850
Currently for SVE ACLE builtins, single tests are used to verify both
clang code generation (when the feature is available) and semantic
error/warning messages (when the feature is unavailable). This
patch moves the semantic testing into dedicated Sema tests.
Differential Revision: https://reviews.llvm.org/D124924
Similar to the existing bitwise reduction builtins, this lowers to a llvm.vector.reduce.mul intrinsic call.
For other reductions, we've tried to share builtins for float/integer vectors, but the fmul reduction intrinsic also take a starting value argument and can either do unordered or serialized, but not reduction-trees as specified for the builtins. However we address fmul support this shouldn't affect the integer case.
Differential Revision: https://reviews.llvm.org/D117829
Compared to the old implementation:
* In C++, we only recurse into aggregate classes.
* Unnamed bit-fields are not printed.
* Constant evaluation is supported.
* Proper conversion is done when passing arguments through `...`.
* Additional arguments are supported and are injected prior to the
format string; this directly supports use with `fprintf`, for example.
* An arbitrary callable can be passed rather than only a function
pointer. In particular, in C++, a function template or overload set is
acceptable.
* All text generated by Clang is printed via `%s` rather than directly;
this avoids issues where Clang's pretty-printing output might itself
contain a `%` character.
* Fields of types that we don't know how to print are printed with a
`"*%p"` format and passed by address to the print function.
* No return value is produced.
Reviewed By: aaron.ballman, erichkeane, yihanaa
Differential Revision: https://reviews.llvm.org/D124221
C89 allowed a type specifier to be elided with the resulting type being
int, aka implicit int behavior. This feature was subsequently removed
in C99 without a deprecation period, so implementations continued to
support the feature. Now, as with implicit function declarations, is a
good time to reevaluate the need for this support.
This patch allows -Wimplicit-int to issue warnings in C89 mode (off by
default), defaults the warning to an error in C99 through C17, and
disables support for the feature entirely in C2x. It also removes a
warning about missing declaration specifiers that really was just an
implicit int warning in disguise and other minor related cleanups.
Similar to the existing bitwise reduction builtins, this lowers to a llvm.vector.reduce.add intrinsic call.
For other reductions, we've tried to share builtins for float/integer vectors, but the fadd reduction intrinsics also take a starting value argument and can either do unordered or serialized, but not reduction-trees as specified for the builtins. However we address fadd support this shouldn't affect the integer case.
(Split off from D117829)
Differential Revision: https://reviews.llvm.org/D124741
clang emit wrong code sequence for `int16`(`short`) to `__fp16` conversion,
and that should fix the code gen directly is the right way I think,
but I found there is a FIXME comment in clang/Basic/TargetInfo.h say
that's should be removed in future so I think just let swich to using
generic LLVM IR rather than llvm.convert.to.fp16 intrinsics code gen
path is enough.
```
/// Check whether llvm intrinsics such as llvm.convert.to.fp16 should be used
/// to convert to and from __fp16.
/// FIXME: This function should be removed once all targets stop using the
/// conversion intrinsics.
virtual bool useFP16ConversionIntrinsics() const {
return true;
}
```
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D124509