This is extended to all `std::` functions that take a reference to a
value and return a reference (or pointer) to that same value: `move`,
`forward`, `move_if_noexcept`, `as_const`, `addressof`, and the
libstdc++-specific function `__addressof`.
We still require these functions to be declared before they can be used,
but don't instantiate their definitions unless their addresses are
taken. Instead, code generation, constant evaluation, and static
analysis are given direct knowledge of their effect.
This change aims to reduce various costs associated with these functions
-- per-instantiation memory costs, compile time and memory costs due to
creating out-of-line copies and inlining them, code size at -O0, and so
on -- so that they are not substantially more expensive than a cast.
Most of these improvements are very small, but I measured a 3% decrease
in -O0 object file size for a simple C++ source file using the standard
library after this change.
We now automatically infer the `const` and `nothrow` attributes on these
now-builtin functions, in particular meaning that we get a warning for
an unused call to one of these functions.
In C++20 onwards, we disallow taking the addresses of these functions,
per the C++20 "addressable function" rule. In earlier language modes, a
compatibility warning is produced but the address can still be taken.
The same infrastructure is extended to the existing MSVC builtin
`__GetExceptionInfo`, which is now only recognized in namespace `std`
like it always should have been.
This is a re-commit of
fc3090109643af8d2da9822d0f99c84742b9c877,
a571f82a50416b767fd3cce0fb5027bb5dfec58c, and
64c045e25b8471bbb572bd29159c294a82a86a25
which were reverted in
e75d8b70370435b0ad10388afba0df45fcf9bfcc
due to a crasher bug where CodeGen would emit a builtin glvalue as an
rvalue if it constant-folds.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D123345
Revert "Extend support for std::move etc to also cover std::as_const and"
Revert "Update test to handle opaque pointers flag flip."
It crashes on libcxx tests https://lab.llvm.org/buildbot/#/builders/85/builds/8174
This reverts commit fc3090109643af8d2da9822d0f99c84742b9c877.
This reverts commit a571f82a50416b767fd3cce0fb5027bb5dfec58c.
This reverts commit 64c045e25b8471bbb572bd29159c294a82a86a25.
std::addressof, plus the libstdc++-specific std::__addressof.
This brings us to parity with the corresponding GCC behavior.
Remove STDBUILTIN macro that ended up not being used.
We still require these functions to be declared before they can be used,
but don't instantiate their definitions unless their addresses are
taken. Instead, code generation, constant evaluation, and static
analysis are given direct knowledge of their effect.
This change aims to reduce various costs associated with these functions
-- per-instantiation memory costs, compile time and memory costs due to
creating out-of-line copies and inlining them, code size at -O0, and so
on -- so that they are not substantially more expensive than a cast.
Most of these improvements are very small, but I measured a 3% decrease
in -O0 object file size for a simple C++ source file using the standard
library after this change.
We now automatically infer the `const` and `nothrow` attributes on these
now-builtin functions, in particular meaning that we get a warning for
an unused call to one of these functions.
In C++20 onwards, we disallow taking the addresses of these functions,
per the C++20 "addressable function" rule. In earlier language modes, a
compatibility warning is produced but the address can still be taken.
The same infrastructure is extended to the existing MSVC builtin
`__GetExceptionInfo`, which is now only recognized in namespace `std`
like it always should have been.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D123345
Currently, clang crashes with i386 target on the following code:
```
void f() {
f + 0xdead000000000000UL;
}
```
This problem is similar to the problem fixed in D104424, but that fix can't handle function pointer case, because `getTypeSizeInCharsIfKnown()` says that size is known and equal to 0 for function type.
This patch prevents bounds checking for function pointer, thus fixes the crash.
Fixes https://github.com/llvm/llvm-project/issues/50463
Reviewed By: erichkeane
Differential Revision: https://reviews.llvm.org/D122748
Add support for builtin_[max|min] which has below prototype:
A builtin_max (A1, A2, A3, ...)
All arguments must have the same type; they must all be float, double, or long double.
Internally use SelectCC to get the result.
Reviewed By: qiucf
Differential Revision: https://reviews.llvm.org/D122478
Index of vset/vget must be a constant integer and be
located in right range.
Reviewed By: kito-cheng
Differential Revision: https://reviews.llvm.org/D122629
Calling an ObjC method from a C function marked with the 'enforce_tcb'
attribute did not produce a warning. Now it does, and on top of that
Objective-C methods can participate in TCBs themselves.
Differential Revision: https://reviews.llvm.org/D122343
__builtin_memcpy_inline doesn't use the usual builtin argument validation code,
so it crashed when receiving wrong number of argument. Add the missing validation
check.
Open issue: https://github.com/llvm/llvm-project/issues/52949
Reviewed By: gchatelet
Differential Revision: https://reviews.llvm.org/D121965
Committed by gchatelet on behalf of "Roy Jacobson <roi.jacobson1@gmail.com>"
If we are equality comparing an FP literal with a value cast from a type
where the literal can't be represented, that's known true or false and
probably a programmer error.
Fixes issue #54222.
https://github.com/llvm/llvm-project/issues/54222
Note - I added the optimizer change with:
9397bdc67eb2
...and as discussed in the post-commit comments, that transform might be
too dangerous without this warning in place, so it was reverted to allow
this change first.
Differential Revision: https://reviews.llvm.org/D121306
This change teaches the Sema logic for `__builtin_memcpy_inline` to implicitly convert arrays passed as arguments to pointers, similarly to regular `memcpy`.
This code will no longer cause a compiler crash:
```
void f(char *p) {
char s[1] = {0};
__builtin_memcpy_inline(p, s, 1);
}
```
rdar://88147527
Differential Revision: https://reviews.llvm.org/D121475
The `__builtin_pdepd` and `__builtin_pextd` are P10 builtins that are meant to
be used under 64-bit only. For instance, when the builtins are compiled under
32-bit mode:
```
$ cat t.c
unsigned long long foo(unsigned long long a, unsigned long long b) {
return __builtin_pextd(a,b);
}
$ clang -c t.c -mcpu=pwr10 -m32
ExpandIntegerResult #0: t31: i64 = llvm.ppc.pextd TargetConstant:i32<6928>, t28, t29
fatal error: error in backend: Do not know how to expand the result of this operator!
```
This patch adds sema checking for these builtins to compile under 64-bit
mode only and on P10. The builtins will emit a diagnostic when they are compiled on
non-P10 compilations and on 32-bit mode.
Differential Revision: https://reviews.llvm.org/D118753
OpenCL C 3.0 __opencl_c_subgroups feature is slightly different
then other equivalent features and extensions (fp64 and 3d image writes):
OpenCL C 3.0 device can support the extension but not the feature.
cl_khr_subgroups requires subgroup independent forward progress.
This patch adjusts the check which is used when translating language
builtins to check either the extension or feature is supported.
Reviewed By: Anastasia
Differential Revision: https://reviews.llvm.org/D118999
This patch implements `__builtin_elementwise_add_sat` and `__builtin_elementwise_sub_sat` builtins.
These map to the add/sub saturated math intrinsics described here:
https://llvm.org/docs/LangRef.html#saturation-arithmetic-intrinsics
With this in place we should then be able to replace the x86 SSE adds/subs intrinsics with these generic variants - it looks like other targets should be able to use these as well (arm/aarch64/webassembly all have similar examples in cgbuiltin).
Differential Revision: https://reviews.llvm.org/D117898
According to the spec, there are some difference between V and Zve64d. For example, the vmulh integer multiply variants that return the high word of the product (vmulh.vv, vmulh.vx, vmulhu.vv, vmulhu.vx, vmulhsu.vv, vmulhsu.vx) are not included for EEW=64 in Zve64*, but V extension does support these instructions. So we should decouple Zve* extensions and the V extension.
Differential Revision: https://reviews.llvm.org/D117854
The `printf` specifier `%n` is not supported on Android's libc and will soon be removed from Fuchsia's
Reviewed By: enh
Differential Revision: https://reviews.llvm.org/D117611
This patch emits an error on AIX and z/OS because XCOFF and GOFF does not currently implement builtin function `CFStringMakeConstantString`. Tests that use this builtin were also disabled.
Reviewed By: SeanP
Differential Revision: https://reviews.llvm.org/D117315
This patch implements two builtins specified in D111529.
The last __builtin_reduce_add will be seperated into another one.
Differential Revision: https://reviews.llvm.org/D116736
When `-ftrivial-auto-var-init=` is enabled, allocas unconditionally
receive auto-initialization since [1].
In certain cases, it turns out, this is causing problems. For example,
when using alloca to add a random stack offset, as the Linux kernel does
on syscall entry [2]. In this case, none of the alloca'd stack memory is
ever used, and initializing it should be controllable; furthermore, it
is not always possible to safely call memset (see [2]).
Introduce `__builtin_alloca_uninitialized()` (and
`__builtin_alloca_with_align_uninitialized`), which never performs
initialization when `-ftrivial-auto-var-init=` is enabled.
[1] https://reviews.llvm.org/D60548
[2] https://lkml.kernel.org/r/YbHTKUjEejZCLyhX@elver.google.com
Reviewed By: glider
Differential Revision: https://reviews.llvm.org/D115440
This patch implements __builtin_reduce_xor as specified in D111529.
Reviewed By: fhahn, aaron.ballman
Differential Revision: https://reviews.llvm.org/D115231
Control-Flow Integrity (CFI) replaces references to address-taken
functions with pointers to the CFI jump table. This is a problem
for low-level code, such as operating system kernels, which may
need the address of an actual function body without the jump table
indirection.
This change adds the __builtin_function_start() builtin, which
accepts an argument that can be constant-evaluated to a function,
and returns the address of the function body.
Link: https://github.com/ClangBuiltLinux/linux/issues/1353
Depends on D108478
Reviewed By: pcc, rjmccall
Differential Revision: https://reviews.llvm.org/D108479
WG14 adopted the _ExtInt feature from Clang for C23, but renamed the
type to be _BitInt. This patch does the vast majority of the work to
rename _ExtInt to _BitInt, which accounts for most of its size. The new
type is exposed in older C modes and all C++ modes as a conforming
extension. However, there are functional changes worth calling out:
* Deprecates _ExtInt with a fix-it to help users migrate to _BitInt.
* Updates the mangling for the type.
* Updates the documentation and adds a release note to warn users what
is going on.
* Adds new diagnostics for use of _BitInt to call out when it's used as
a Clang extension or as a pre-C23 compatibility concern.
* Adds new tests for the new diagnostic behaviors.
I want to call out the ABI break specifically. We do not believe that
this break will cause a significant imposition for early adopters of
the feature, and so this is being done as a full break. If it turns out
there are critical uses where recompilation is not an option for some
reason, we can consider using ABI tags to ease the transition.
Add an AtomicScopeModel for HIP and support for OpenCL builtins
that are missing in HIP.
Patch by: Michael Liao
Revised by: Anshil Ghandi
Reviewed by: Yaxun Liu
Differential Revision: https://reviews.llvm.org/D113925
Calls to MMA builtins that take pointer to void
do not accept other pointers/arrays whereas normal
functions with the same parameter do. This patch
allows MMA built-ins to accept non-void pointers
and arrays.
Reviewed By: nemanjai
Differential Revision: https://reviews.llvm.org/D113306
Implement two builtins to pack/unpack IBM extended long double float,
according to GCC 'Basic PowerPC Builtin Functions Available ISA 2.05'.
Reviewed By: jsji
Differential Revision: https://reviews.llvm.org/D112055
This patch implements __builtin_reduce_max and __builtin_reduce_min as
specified in D111529.
The order of operations does not matter for min or max reductions and
they can be directly lowered to the corresponding
llvm.vector.reduce.{fmin,fmax,umin,umax,smin,smax} intrinsic calls.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D112001
This change fixes a crash where a NULL fd was used to emit a diagnostic.
Instead of crashing, just avoid printing the declaration name when there's no
associated function declaration.
Differential Revision: https://reviews.llvm.org/D109402
Add `__c11_atomic_fetch_nand` builtin to language extensions and support `__atomic_fetch_nand` libcall in compiler-rt.
Reviewed By: theraven
Differential Revision: https://reviews.llvm.org/D112400
- `[[format(archetype, fmt-idx, ellipsis)]]` specifies that a function accepts a
format string and arguments according to `archetype`. This is how Clang
type-checks `printf` arguments based on the format string.
- Clang has a `-Wformat-nonliteral` warning that is triggered when a function
with the `format` attribute is called with a format string that is not
inspectable because it isn't constant. This warning is suppressed if the
caller has the `format` attribute itself and the format argument to the callee
is the caller's own format parameter.
- When using the `format` attribute on a block, Clang wouldn't recognize its
format parameter when calling another function with the format attribute. This
would cause unsuppressed -Wformat-nonliteral warnings for no supported reason.
Reviewed By: ahatanak
Differential Revision: https://reviews.llvm.org/D112569
Radar-Id: rdar://84603673
This patch implements __builtin_elementwise_abs as specified in
D111529.
Reviewed By: aaron.ballman, scanon
Differential Revision: https://reviews.llvm.org/D111986
Replace some custom matrix diagnostic kinds with the more generic
err_builtin_invalid_arg_type introduced in D111985.
Reviewed By: aaron.ballman, erichkeane
Differential Revision: https://reviews.llvm.org/D112532
This patch implements __builtin_elementwise_max and
__builtin_elementwise_min, as specified in D111529.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D111985
