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[compiler-rt] [scudo] Use -mcrc32 on x86 when available

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Update the hardware CRC32 logic in scudo to support using `-mcrc32`
instead of `-msse4.2`.  The CRC32 intrinsics use the former flag
in the newer compiler versions, e.g. in clang since 12fa608af4.
With these compilers, passing `-msse4.2` is insufficient to enable
the instructions and causes build failures when `-march` does not enable
CRC32:

    /var/tmp/portage/sys-libs/compiler-rt-sanitizers-14.0.0/work/compiler-rt/lib/scudo/scudo_crc32.cpp:20:10: error: always_inline function '_mm_crc32_u32' requires target feature 'crc32', but would be inlined into function 'computeHardwareCRC32' that is compiled without support for 'crc32'
      return CRC32_INTRINSIC(Crc, Data);
             ^
    /var/tmp/portage/sys-libs/compiler-rt-sanitizers-14.0.0/work/compiler-rt/lib/scudo/scudo_crc32.h:27:27: note: expanded from macro 'CRC32_INTRINSIC'
    #  define CRC32_INTRINSIC FIRST_32_SECOND_64(_mm_crc32_u32, _mm_crc32_u64)
                              ^
    /var/tmp/portage/sys-libs/compiler-rt-sanitizers-14.0.0/work/compiler-rt/lib/scudo/../sanitizer_common/sanitizer_platform.h:132:36: note: expanded from macro 'FIRST_32_SECOND_64'
    #  define FIRST_32_SECOND_64(a, b) (a)
                                       ^
    1 error generated.

For backwards compatibility, use `-mcrc32` when available and fall back
to `-msse4.2`.  The `<smmintrin.h>` header remains in use as it still
works and is compatible with GCC, while clang's `<crc32intrin.h>`
is not.

Originally reported in https://bugs.gentoo.org/835870.

Differential Revision: https://reviews.llvm.org/D122789
This commit is contained in:
Michał Górny 2022-03-31 09:55:25 +02:00
parent 97417e0300
commit 09b53121c3
9 changed files with 27 additions and 18 deletions
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1
compiler-rt/cmake/config-ix.cmake
View file

@ -78,6 +78,7 @@ check_cxx_compiler_flag(-fno-profile-generate COMPILER_RT_HAS_FNO_PROFILE_GENERA
check_cxx_compiler_flag(-fno-profile-instr-generate COMPILER_RT_HAS_FNO_PROFILE_INSTR_GENERATE_FLAG)
check_cxx_compiler_flag(-fno-profile-instr-use COMPILER_RT_HAS_FNO_PROFILE_INSTR_USE_FLAG)
check_cxx_compiler_flag(-fno-coverage-mapping COMPILER_RT_HAS_FNO_COVERAGE_MAPPING_FLAG)
check_cxx_compiler_flag("-Werror -mcrc32" COMPILER_RT_HAS_MCRC32_FLAG)
check_cxx_compiler_flag("-Werror -msse3" COMPILER_RT_HAS_MSSE3_FLAG)
check_cxx_compiler_flag("-Werror -msse4.2" COMPILER_RT_HAS_MSSE4_2_FLAG)
check_cxx_compiler_flag(--sysroot=. COMPILER_RT_HAS_SYSROOT_FLAG)

7
compiler-rt/lib/scudo/CMakeLists.txt
View file

@ -86,8 +86,11 @@ set(SCUDO_HEADERS
scudo_tsd_shared.inc
scudo_utils.h)
# Enable the SSE 4.2 instruction set for scudo_crc32.cpp, if available.
if (COMPILER_RT_HAS_MSSE4_2_FLAG)
# Enable the necessary instruction set for scudo_crc32.cpp, if available.
# Newer compiler versions use -mcrc32 rather than -msse4.2.
if (COMPILER_RT_HAS_MCRC32_FLAG)
set_source_files_properties(scudo_crc32.cpp PROPERTIES COMPILE_FLAGS -mcrc32)
elseif (COMPILER_RT_HAS_MSSE4_2_FLAG)
set_source_files_properties(scudo_crc32.cpp PROPERTIES COMPILE_FLAGS -msse4.2)
endif()

4
compiler-rt/lib/scudo/scudo_allocator.cpp
View file

@ -49,7 +49,7 @@ inline u32 computeCRC32(u32 Crc, uptr Value, uptr *Array, uptr ArraySize) {
// as opposed to only for scudo_crc32.cpp. This means that other hardware
// specific instructions were likely emitted at other places, and as a
// result there is no reason to not use it here.
#if defined(__SSE4_2__) || defined(__ARM_FEATURE_CRC32)
#if defined(__CRC32__) || defined(__SSE4_2__) || defined(__ARM_FEATURE_CRC32)
Crc = CRC32_INTRINSIC(Crc, Value);
for (uptr i = 0; i < ArraySize; i++)
Crc = CRC32_INTRINSIC(Crc, Array[i]);
@ -65,7 +65,7 @@ inline u32 computeCRC32(u32 Crc, uptr Value, uptr *Array, uptr ArraySize) {
for (uptr i = 0; i < ArraySize; i++)
Crc = computeSoftwareCRC32(Crc, Array[i]);
return Crc;
#endif // defined(__SSE4_2__) || defined(__ARM_FEATURE_CRC32)
#endif // defined(__CRC32__) || defined(__SSE4_2__) || defined(__ARM_FEATURE_CRC32)
}
static BackendT &getBackend();

4
compiler-rt/lib/scudo/scudo_crc32.cpp
View file

@ -15,10 +15,10 @@
namespace __scudo {
#if defined(__SSE4_2__) || defined(__ARM_FEATURE_CRC32)
#if defined(__CRC32__) || defined(__SSE4_2__) || defined(__ARM_FEATURE_CRC32)
u32 computeHardwareCRC32(u32 Crc, uptr Data) {
return CRC32_INTRINSIC(Crc, Data);
}
#endif // defined(__SSE4_2__) || defined(__ARM_FEATURE_CRC32)
#endif // defined(__CRC32__) || defined(__SSE4_2__) || defined(__ARM_FEATURE_CRC32)
} // namespace __scudo

9
compiler-rt/lib/scudo/scudo_crc32.h
View file

@ -16,13 +16,14 @@
#include "sanitizer_common/sanitizer_internal_defs.h"
// Hardware CRC32 is supported at compilation via the following:
// - for i386 & x86_64: -msse4.2
// - for i386 & x86_64: -mcrc32 (earlier: -msse4.2)
// - for ARM & AArch64: -march=armv8-a+crc or -mcrc
// An additional check must be performed at runtime as well to make sure the
// emitted instructions are valid on the target host.
#if defined(__SSE4_2__) || defined(__ARM_FEATURE_CRC32)
# ifdef __SSE4_2__
#if defined(__CRC32__) || defined(__SSE4_2__) || defined(__ARM_FEATURE_CRC32)
# if defined(__CRC32__) || defined(__SSE4_2__)
// NB: clang has <crc32intrin.h> but GCC does not
# include <smmintrin.h>
# define CRC32_INTRINSIC FIRST_32_SECOND_64(_mm_crc32_u32, _mm_crc32_u64)
# endif
@ -30,7 +31,7 @@
# include <arm_acle.h>
# define CRC32_INTRINSIC FIRST_32_SECOND_64(__crc32cw, __crc32cd)
# endif
#endif // defined(__SSE4_2__) || defined(__ARM_FEATURE_CRC32)
#endif // defined(__CRC32__) || defined(__SSE4_2__) || defined(__ARM_FEATURE_CRC32)
namespace __scudo {

7
compiler-rt/lib/scudo/standalone/CMakeLists.txt
View file

@ -97,8 +97,11 @@ set(SCUDO_SOURCES
string_utils.cpp
)
# Enable the SSE 4.2 instruction set for crc32_hw.cpp, if available.
if (COMPILER_RT_HAS_MSSE4_2_FLAG)
# Enable the necessary instruction set for scudo_crc32.cpp, if available.
# Newer compiler versions use -mcrc32 rather than -msse4.2.
if (COMPILER_RT_HAS_MCRC32_FLAG)
set_source_files_properties(crc32_hw.cpp PROPERTIES COMPILE_FLAGS -mcrc32)
elseif (COMPILER_RT_HAS_MSSE4_2_FLAG)
set_source_files_properties(crc32_hw.cpp PROPERTIES COMPILE_FLAGS -msse4.2)
endif()

5
compiler-rt/lib/scudo/standalone/checksum.h
View file

@ -12,12 +12,13 @@
#include "internal_defs.h"
// Hardware CRC32 is supported at compilation via the following:
// - for i386 & x86_64: -msse4.2
// - for i386 & x86_64: -mcrc32 (earlier: -msse4.2)
// - for ARM & AArch64: -march=armv8-a+crc or -mcrc
// An additional check must be performed at runtime as well to make sure the
// emitted instructions are valid on the target host.
#ifdef __SSE4_2__
#if defined(__CRC32__) || defined(__SSE4_2__)
// NB: clang has <crc32intrin.h> but GCC does not
#include <smmintrin.h>
#define CRC32_INTRINSIC FIRST_32_SECOND_64(_mm_crc32_u32, _mm_crc32_u64)
#endif

4
compiler-rt/lib/scudo/standalone/chunk.h
View file

@ -25,7 +25,7 @@ inline u16 computeChecksum(u32 Seed, uptr Value, uptr *Array, uptr ArraySize) {
// as opposed to only for crc32_hw.cpp. This means that other hardware
// specific instructions were likely emitted at other places, and as a result
// there is no reason to not use it here.
#if defined(__SSE4_2__) || defined(__ARM_FEATURE_CRC32)
#if defined(__CRC32__) || defined(__SSE4_2__) || defined(__ARM_FEATURE_CRC32)
u32 Crc = static_cast<u32>(CRC32_INTRINSIC(Seed, Value));
for (uptr I = 0; I < ArraySize; I++)
Crc = static_cast<u32>(CRC32_INTRINSIC(Crc, Array[I]));
@ -42,7 +42,7 @@ inline u16 computeChecksum(u32 Seed, uptr Value, uptr *Array, uptr ArraySize) {
Checksum = computeBSDChecksum(Checksum, Array[I]);
return Checksum;
}
#endif // defined(__SSE4_2__) || defined(__ARM_FEATURE_CRC32)
#endif // defined(__CRC32__) || defined(__SSE4_2__) || defined(__ARM_FEATURE_CRC32)
}
namespace Chunk {

4
compiler-rt/lib/scudo/standalone/crc32_hw.cpp
View file

@ -10,10 +10,10 @@
namespace scudo {
#if defined(__SSE4_2__) || defined(__ARM_FEATURE_CRC32)
#if defined(__CRC32__) || defined(__SSE4_2__) || defined(__ARM_FEATURE_CRC32)
u32 computeHardwareCRC32(u32 Crc, uptr Data) {
return static_cast<u32>(CRC32_INTRINSIC(Crc, Data));
}
#endif // defined(__SSE4_2__) || defined(__ARM_FEATURE_CRC32)
#endif // defined(__CRC32__) || defined(__SSE4_2__) || defined(__ARM_FEATURE_CRC32)
} // namespace scudo