C89 had a questionable feature where the compiler would implicitly
declare a function that the user called but was never previously
declared. The resulting function would be globally declared as
extern int func(); -- a function without a prototype which accepts zero
or more arguments.
C99 removed support for this questionable feature due to severe
security concerns. However, there was no deprecation period; C89 had
the feature, C99 didn't. So Clang (and GCC) both supported the
functionality as an extension in C99 and later modes.
C2x no longer supports that function signature as it now requires all
functions to have a prototype, and given the known security issues with
the feature, continuing to support it as an extension is not tenable.
This patch changes the diagnostic behavior for the
-Wimplicit-function-declaration warning group depending on the language
mode in effect. We continue to warn by default in C89 mode (due to the
feature being dangerous to use). However, because this feature will not
be supported in C2x mode, we've diagnosed it as being invalid for so
long, the security concerns with the feature, and the trivial
workaround for users (declare the function), we now default the
extension warning to an error in C99-C17 mode. This still gives users
an easy workaround if they are extensively using the extension in those
modes (they can disable the warning or use -Wno-error to downgrade the
error), but the new diagnostic makes it more clear that this feature is
not supported and should be avoided. In C2x mode, we no longer allow an
implicit function to be defined and treat the situation the same as any
other lookup failure.
Differential Revision: https://reviews.llvm.org/D122983
A significant number of our tests in C accidentally use functions
without prototypes. This patch converts the function signatures to have
a prototype for the situations where the test is not specific to K&R C
declarations. e.g.,
void func();
becomes
void func(void);
This is the tenth batch of tests being updated (there are a
significant number of other tests left to be updated).
D117898 added the generic __builtin_elementwise_add_sat and __builtin_elementwise_sub_sat with the same integer behaviour as the SSE/AVX instructions
This patch removes the __builtin_ia32_padd/psub saturated intrinsics and just uses the generics - the existing tests see no changes:
__m256i test_mm256_adds_epi8(__m256i a, __m256i b) {
// CHECK-LABEL: test_mm256_adds_epi8
// CHECK: call <32 x i8> @llvm.sadd.sat.v32i8(<32 x i8> %{{.*}}, <32 x i8> %{{.*}})
return _mm256_adds_epi8(a, b);
}
D111985 added the generic `__builtin_elementwise_max` and `__builtin_elementwise_min` intrinsics with the same integer behaviour as the SSE/AVX instructions
This patch removes the `__builtin_ia32_pmax/min` intrinsics and just uses `__builtin_elementwise_max/min` - the existing tests see no changes:
```
__m256i test_mm256_max_epu32(__m256i a, __m256i b) {
// CHECK-LABEL: test_mm256_max_epu32
// CHECK: call <8 x i32> @llvm.umax.v8i32(<8 x i32> %{{.*}}, <8 x i32> %{{.*}})
return _mm256_max_epu32(a, b);
}
```
This requires us to add a `__v64qs` explicitly signed char vector type (we already have `__v16qs` and `__v32qs`).
Sibling patch to D117791
Differential Revision: https://reviews.llvm.org/D117798
D111986 added the generic `__builtin_elementwise_abs()` intrinsic with the same integer absolute behaviour as the SSE/AVX instructions (abs(INT_MIN) == INT_MIN)
This patch removes the `__builtin_ia32_pabs*` intrinsics and just uses `__builtin_elementwise_abs` - the existing tests see no changes:
```
__m256i test_mm256_abs_epi8(__m256i a) {
// CHECK-LABEL: test_mm256_abs_epi8
// CHECK: [[ABS:%.*]] = call <32 x i8> @llvm.abs.v32i8(<32 x i8> %{{.*}}, i1 false)
return _mm256_abs_epi8(a);
}
```
This requires us to add a `__v64qs` explicitly signed char vector type (we already have `__v16qs` and `__v32qs`).
Differential Revision: https://reviews.llvm.org/D117791
D111985 added the generic `__builtin_elementwise_max` and `__builtin_elementwise_min` intrinsics with the same integer behaviour as the SSE/AVX instructions
This patch removes the `__builtin_ia32_pmax/min` intrinsics and just uses `__builtin_elementwise_max/min` - the existing tests see no changes:
```
__m256i test_mm256_max_epu32(__m256i a, __m256i b) {
// CHECK-LABEL: test_mm256_max_epu32
// CHECK: call <8 x i32> @llvm.umax.v8i32(<8 x i32> %{{.*}}, <8 x i32> %{{.*}})
return _mm256_max_epu32(a, b);
}
```
This requires us to add a `__v64qs` explicitly signed char vector type (we already have `__v16qs` and `__v32qs`).
Sibling patch to D117791
Differential Revision: https://reviews.llvm.org/D117798
D111986 added the generic `__builtin_elementwise_abs()` intrinsic with the same integer absolute behaviour as the SSE/AVX instructions (abs(INT_MIN) == INT_MIN)
This patch removes the `__builtin_ia32_pabs*` intrinsics and just uses `__builtin_elementwise_abs` - the existing tests see no changes:
```
__m256i test_mm256_abs_epi8(__m256i a) {
// CHECK-LABEL: test_mm256_abs_epi8
// CHECK: [[ABS:%.*]] = call <32 x i8> @llvm.abs.v32i8(<32 x i8> %{{.*}}, i1 false)
return _mm256_abs_epi8(a);
}
```
This requires us to add a `__v64qs` explicitly signed char vector type (we already have `__v16qs` and `__v32qs`).
Differential Revision: https://reviews.llvm.org/D117791
These builtins should work with immediate or variable shift operand for
gcc compatibility.
Differential Revision: https://reviews.llvm.org/D62850
llvm-svn: 362786
Summary: According to C99 standard long long is at least 64 bits in
size. However, OpenCL C defines long long as 128 bit signed
integer. This prevents one to use x86 builtins when compiling OpenCL C
code for x86 targets. The patch changes long long to long for OpenCL
only.
Patch by: Alexander Batashev <alexander.batashev@intel.com>
Reviewers: craig.topper, Ka-Ka, eandrews, erichkeane, Anastasia
Reviewed By: Ka-Ka, erichkeane, Anastasia
Subscribers: a.elovikov, yaxunl, Anastasia, cfe-commits, ivankara, etyurin, asavonic
Tags: #clang
Differential Revision: https://reviews.llvm.org/D62580
llvm-svn: 362391
Summary:
This patch attempts to redo what was tried in r278783, but was reverted.
These intrinsics should be available on non-windows platforms with "xsave" feature check. But on Windows platforms they shouldn't have feature check since that's how MSVC behaves.
To accomplish this I've added a MS builtin with no feature check. And a normal gcc builtin with a feature check. When _MSC_VER is not defined _xgetbv/_xsetbv will be macros pointing to the gcc builtin name.
I've moved the forward declarations from intrin.h to immintrin.h to match the MSDN documentation and used that as the header file for the MS builtin.
I'm not super happy with this implementation, and I'm open to suggestions for better ways to do it.
Reviewers: rnk, RKSimon, spatel
Reviewed By: rnk
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D56686
llvm-svn: 351160
I believe this is safe assuming default default FP environment. The conversion might be inexact, but it can never overflow the FP type so this shouldn't be undefined behavior for the uitofp/sitofp instructions.
We already do something similar for scalar conversions.
Differential Revision: https://reviews.llvm.org/D46863
llvm-svn: 332882
in gcc by https://gcc.gnu.org/ml/gcc-cvs/2018-04/msg00534.html.
The -mibt feature flag is being removed, and the -fcf-protection
option now also defines a CET macro and causes errors when used
on non-X86 targets, while X86 targets no longer check for -mibt
and -mshstk to determine if -fcf-protection is supported. -mshstk
is now used only to determine availability of shadow stack intrinsics.
Comes with an LLVM patch (D46882).
Patch by mike.dvoretsky
Differential Revision: https://reviews.llvm.org/D46881
llvm-svn: 332704
The WBNOINVD instruction writes back all modified
cache lines in the processor’s internal cache to main memory
but does not invalidate (flush) the internal caches.
Reviewers: craig.topper, zvi, ashlykov
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D43817
llvm-svn: 329848
Shadow stack solution introduces a new stack for return addresses only.
The stack has a Shadow Stack Pointer (SSP) that points to the last address to which we expect to return.
If we return to a different address an exception is triggered.
This patch includes shadow stack intrinsics as well as the corresponding CET header.
It includes CET clang flags for shadow stack and Indirect Branch Tracking.
For more information, please see the following:
https://software.intel.com/sites/default/files/managed/4d/2a/control-flow-enforcement-technology-preview.pdf
Differential Revision: https://reviews.llvm.org/D40224
Change-Id: I79ad0925a028bbc94c8ecad75f6daa2f214171f1
llvm-svn: 318995
1. Adds the command line flag for clzero.
2. Includes the clzero flag under znver1.
3. Defines the macro for clzero.
4. Adds a new file which has the intrinsic definition for clzero instruction.
Patch by Ganesh Gopalasubramanian with some additional tests from me.
Differential revision: https://reviews.llvm.org/D29386
llvm-svn: 294559
D20859 and D20860 attempted to replace the SSE (V)CVTTPS2DQ and VCVTTPD2DQ truncating conversions with generic IR instead.
It turns out that the behaviour of these intrinsics is different enough from generic IR that this will cause problems, INF/NAN/out of range values are guaranteed to result in a 0x80000000 value - which plays havoc with constant folding which converts them to either zero or UNDEF. This is also an issue with the scalar implementations (which were already generic IR and what I was trying to match).
This patch changes both scalar and packed versions back to using x86-specific builtins.
It also deals with the other scalar conversion cases that are runtime rounding mode dependent and can have similar issues with constant folding.
Differential Revision: https://reviews.llvm.org/D22105
llvm-svn: 276102
We can now use __builtin_nontemporal_store instead of target specific builtins for naturally aligned nontemporal stores which avoids the need for handling in CGBuiltin.cpp
The scalar integer nontemporal (unaligned) store builtins will have to wait as __builtin_nontemporal_store currently assumes natural alignment and doesn't accept the 'packed struct' trick that we use for normal unaligned load/stores.
The nontemporal loads require further backend support before we can safely convert them to __builtin_nontemporal_load
Differential Revision: http://reviews.llvm.org/D21272
llvm-svn: 272540
The 'cvtt' truncation (round to zero) conversions can be safely represented as generic __builtin_convertvector (fptosi) calls instead of x86 intrinsics. We already do this (implicitly) for the scalar equivalents.
Note: I looked at updating _mm_cvttpd_epi32 as well but this still requires a lot more backend work to correctly lower (both for debug and optimized builds).
Differential Revision: http://reviews.llvm.org/D20859
llvm-svn: 271436
The VPMOVSX and (V)PMOVZX sign/zero extension intrinsics can be safely represented as generic __builtin_convertvector calls instead of x86 intrinsics.
This patch removes the clang builtins and their use in the sse2/avx headers - a companion patch will remove/auto-upgrade the llvm intrinsics.
Note: We already did this for SSE41 PMOVSX sometime ago.
Differential Revision: http://reviews.llvm.org/D20684
llvm-svn: 271106
Both the (V)CVTDQ2PD(Y) (i32 to f64) and (V)CVTPS2PD(Y) (f32 to f64) conversion instructions are lossless and can be safely represented as generic __builtin_convertvector calls instead of x86 intrinsics without affecting final codegen.
This patch removes the clang builtins and their use in the sse2/avx headers - a future patch will deal with removing the llvm intrinsics, but that will require a bit more work.
Differential Revision: http://reviews.llvm.org/D20528
llvm-svn: 270499
Summary:
MONITORX/MWAITX instructions provide similar capability to the MONITOR/MWAIT
pair while adding a timer function, such that another termination of the MWAITX
instruction occurs when the timer expires. The presence of the MONITORX and
MWAITX instructions is indicated by CPUID 8000_0001, ECX, bit 29.
The MONITORX and MWAITX instructions are intercepted by the same bits that
intercept MONITOR and MWAIT. MONITORX instruction establishes a range to be
monitored. MWAITX instruction causes the processor to stop instruction
execution and enter an implementation-dependent optimized state until
occurrence of a class of events.
Opcode of MONITORX instruction is "0F 01 FA". Opcode of MWAITX instruction is
"0F 01 FB". These opcode information is used in adding tests for the
disassembler.
These instructions are enabled for AMD's bdver4 architecture.
Patch by Ganesh Gopalasubramanian!
Reviewers: echristo, craig.topper
Subscribers: RKSimon, joker.eph, llvm-commits, cfe-commits
Differential Revision: http://reviews.llvm.org/D19796
llvm-svn: 269907
According to the Intel documentation, the mask operand of a maskload and
maskstore intrinsics is always a vector of packed integer/long integer values.
This patch introduces the following two changes:
1. It fixes the avx maskload/store intrinsic definitions in avxintrin.h.
2. It changes BuiltinsX86.def to match the correct gcc definitions for avx
maskload/store (see D13861 for more details).
Differential Revision: http://reviews.llvm.org/D13861
llvm-svn: 250816
128-bit vector integer sign extensions correctly lower to the pmovsx instructions even for debug builds.
This patch removes the builtins and reimplements the _mm_cvtepi*_epi* intrinsics __using builtin_shufflevector (to extract the bottom most subvector) and __builtin_convertvector (to actually perform the sign extension).
Differential Revision: http://reviews.llvm.org/D12835
llvm-svn: 248092
Add intrinsics for the FXSR instructions (FXSAVE/FXSAVE64/FXRSTOR/FXRSTOR64)
These were previously declared in Intrin.h for MSVC compatibility, but now
that we have them implemented, these declarations can be removed.
llvm-svn: 241053
This is very much like D8088 (checked in at r231792).
Now that we've replaced the vinsertf128 intrinsics,
do the same for their extract twins.
Differential Revision: http://reviews.llvm.org/D8275
llvm-svn: 232052
We want to replace as much custom x86 shuffling via intrinsics
as possible because pushing the code down the generic shuffle
optimization path allows for better codegen and less complexity
in LLVM.
This is the sibling patch for the LLVM half of this change:
http://reviews.llvm.org/D8086
Differential Revision: http://reviews.llvm.org/D8088
llvm-svn: 231792
made the 8-bit masks actually 8-bit arguments to these intrinsics.
These builtins are a mess. Many were missing the I qualifier which
I added where obviously correct. Most aren't tested, but I've updated
the relevant tests. I've tried to catch all the things that should
become 'c' in this round.
It's also frustrating because the set of these is really ad-hoc and
doesn't really map that cleanly to the set supported by either GCC or
LLVM. Oh well...
llvm-svn: 217311
Aaron Ballman