[compiler-rt] fd1da78 - [compiler-rt] [scudo] Use -mcrc32 on x86 when available

Michał Górny via llvm-commits llvm-commits at lists.llvm.org
Fri Apr 1 04:00:47 PDT 2022


Author: Michał Górny
Date: 2022-04-01T13:00:21+02:00
New Revision: fd1da784ac644492f8ca40064baf3ef360352f55

URL: https://github.com/llvm/llvm-project/commit/fd1da784ac644492f8ca40064baf3ef360352f55
DIFF: https://github.com/llvm/llvm-project/commit/fd1da784ac644492f8ca40064baf3ef360352f55.diff

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

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 12fa608af44a.
With these versions of clang, passing `-msse4.2` is insufficient
to enable the instructions and causes build failures when `-march` does
not enable CRC32 implicitly:

    /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.

Use __builtin_ia32*() rather than _mm_crc32*() when using `-mcrc32`
to preserve compatibility with GCC.  _mm_crc32*() are aliases
to __builtin_ia32*() in both compilers but GCC requires `-msse4.2`
for the former, while both use `-mcrc32` for the latter.

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

Differential Revision: https://reviews.llvm.org/D122789

Added: 
    

Modified: 
    compiler-rt/cmake/config-ix.cmake
    compiler-rt/lib/scudo/CMakeLists.txt
    compiler-rt/lib/scudo/scudo_allocator.cpp
    compiler-rt/lib/scudo/scudo_crc32.cpp
    compiler-rt/lib/scudo/scudo_crc32.h
    compiler-rt/lib/scudo/standalone/CMakeLists.txt
    compiler-rt/lib/scudo/standalone/checksum.h
    compiler-rt/lib/scudo/standalone/chunk.h
    compiler-rt/lib/scudo/standalone/crc32_hw.cpp

Removed: 
    


################################################################################
diff  --git a/compiler-rt/cmake/config-ix.cmake b/compiler-rt/cmake/config-ix.cmake
index 3ad2d6a932dba..33e6e1c80cdb3 100644
--- a/compiler-rt/cmake/config-ix.cmake
+++ b/compiler-rt/cmake/config-ix.cmake
@@ -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)

diff  --git a/compiler-rt/lib/scudo/CMakeLists.txt b/compiler-rt/lib/scudo/CMakeLists.txt
index 995e853e2a4d7..31a6976960f76 100644
--- a/compiler-rt/lib/scudo/CMakeLists.txt
+++ b/compiler-rt/lib/scudo/CMakeLists.txt
@@ -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()
 

diff  --git a/compiler-rt/lib/scudo/scudo_allocator.cpp b/compiler-rt/lib/scudo/scudo_allocator.cpp
index 5b6ac8b354934..6a6b577ab0025 100644
--- a/compiler-rt/lib/scudo/scudo_allocator.cpp
+++ b/compiler-rt/lib/scudo/scudo_allocator.cpp
@@ -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();

diff  --git a/compiler-rt/lib/scudo/scudo_crc32.cpp b/compiler-rt/lib/scudo/scudo_crc32.cpp
index 87473505fe792..137c44c5c1cda 100644
--- a/compiler-rt/lib/scudo/scudo_crc32.cpp
+++ b/compiler-rt/lib/scudo/scudo_crc32.cpp
@@ -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

diff  --git a/compiler-rt/lib/scudo/scudo_crc32.h b/compiler-rt/lib/scudo/scudo_crc32.h
index ef40595a56d1f..4314d30e929fe 100644
--- a/compiler-rt/lib/scudo/scudo_crc32.h
+++ b/compiler-rt/lib/scudo/scudo_crc32.h
@@ -16,13 +16,17 @@
 #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__)
+// NB: clang has <crc32intrin.h> but GCC does not
+#  include <smmintrin.h>
+#  define CRC32_INTRINSIC FIRST_32_SECOND_64(__builtin_ia32_crc32si, __builtin_ia32_crc32di)
+# elif defined(__SSE4_2__)
 #  include <smmintrin.h>
 #  define CRC32_INTRINSIC FIRST_32_SECOND_64(_mm_crc32_u32, _mm_crc32_u64)
 # endif
@@ -30,7 +34,7 @@
 #  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 {
 

diff  --git a/compiler-rt/lib/scudo/standalone/CMakeLists.txt b/compiler-rt/lib/scudo/standalone/CMakeLists.txt
index 739f131bdefdf..ae5c354768c89 100644
--- a/compiler-rt/lib/scudo/standalone/CMakeLists.txt
+++ b/compiler-rt/lib/scudo/standalone/CMakeLists.txt
@@ -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()
 

diff  --git a/compiler-rt/lib/scudo/standalone/checksum.h b/compiler-rt/lib/scudo/standalone/checksum.h
index a63b1b4f064d1..0f787ce2b5cde 100644
--- a/compiler-rt/lib/scudo/standalone/checksum.h
+++ b/compiler-rt/lib/scudo/standalone/checksum.h
@@ -12,12 +12,16 @@
 #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__)
+// NB: clang has <crc32intrin.h> but GCC does not
+#include <smmintrin.h>
+#define CRC32_INTRINSIC FIRST_32_SECOND_64(__builtin_ia32_crc32si, __builtin_ia32_crc32di)
+#elif defined(__SSE4_2__)
 #include <smmintrin.h>
 #define CRC32_INTRINSIC FIRST_32_SECOND_64(_mm_crc32_u32, _mm_crc32_u64)
 #endif

diff  --git a/compiler-rt/lib/scudo/standalone/chunk.h b/compiler-rt/lib/scudo/standalone/chunk.h
index 69b8e1b12a91c..0581420dfc99a 100644
--- a/compiler-rt/lib/scudo/standalone/chunk.h
+++ b/compiler-rt/lib/scudo/standalone/chunk.h
@@ -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 {

diff  --git a/compiler-rt/lib/scudo/standalone/crc32_hw.cpp b/compiler-rt/lib/scudo/standalone/crc32_hw.cpp
index 62841ba510199..d13c615498fff 100644
--- a/compiler-rt/lib/scudo/standalone/crc32_hw.cpp
+++ b/compiler-rt/lib/scudo/standalone/crc32_hw.cpp
@@ -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


        


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