Author: Simon Pilgrim Date: 2020-08-20T21:38:04+01:00 New Revision: cff0db08761f310dfebb5b41b307d2c12bda85fc
URL: https://github.com/llvm/llvm-project/commit/cff0db08761f310dfebb5b41b307d2c12bda85fc DIFF: https://github.com/llvm/llvm-project/commit/cff0db08761f310dfebb5b41b307d2c12bda85fc.diff LOG: [X86] Enable constexpr on POPCNT intrinsics (PR31446) This is a first step patch to enable constexpr support and testing to a large number of x86 intrinsics. All I've done here is provide a DEFAULT_FN_ATTRS_CONSTEXPR variant to our existing DEFAULT_FN_ATTRS tag approach that adds constexpr on c++ builds. The clang cuda headers do something similar. I've started with POPCNT mainly as its tiny and are wrappers to generic __builtin_* intrinsics which already act as constexpr. Differential Revision: https://reviews.llvm.org/D86229 Added: Modified: clang/docs/ReleaseNotes.rst clang/lib/Headers/popcntintrin.h clang/test/CodeGen/popcnt-builtins.c Removed: ################################################################################ diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index 03eca8a26843..f97e95a55c0e 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -153,6 +153,12 @@ CUDA Support in Clang - ... +X86 Support in Clang +-------------------- + +- The x86 intrinsics ``_mm_popcnt_u32`` and ``_mm_popcnt_u64`` may now be used + within constexpr expressions. + Internal API Changes -------------------- diff --git a/clang/lib/Headers/popcntintrin.h b/clang/lib/Headers/popcntintrin.h index 312901014796..0aa94aecda5b 100644 --- a/clang/lib/Headers/popcntintrin.h +++ b/clang/lib/Headers/popcntintrin.h @@ -13,6 +13,12 @@ /* Define the default attributes for the functions in this file. */ #define __DEFAULT_FN_ATTRS __attribute__((__always_inline__, __nodebug__, __target__("popcnt"))) +#if defined(__cplusplus) && (__cplusplus >= 201103L) +#define __DEFAULT_FN_ATTRS_CONSTEXPR __DEFAULT_FN_ATTRS constexpr +#else +#define __DEFAULT_FN_ATTRS_CONSTEXPR __DEFAULT_FN_ATTRS +#endif + /// Counts the number of bits in the source operand having a value of 1. /// /// \headerfile <x86intrin.h> @@ -23,7 +29,7 @@ /// An unsigned 32-bit integer operand. /// \returns A 32-bit integer containing the number of bits with value 1 in the /// source operand. -static __inline__ int __DEFAULT_FN_ATTRS +static __inline__ int __DEFAULT_FN_ATTRS_CONSTEXPR _mm_popcnt_u32(unsigned int __A) { return __builtin_popcount(__A); @@ -40,7 +46,7 @@ _mm_popcnt_u32(unsigned int __A) /// An unsigned 64-bit integer operand. /// \returns A 64-bit integer containing the number of bits with value 1 in the /// source operand. -static __inline__ long long __DEFAULT_FN_ATTRS +static __inline__ long long __DEFAULT_FN_ATTRS_CONSTEXPR _mm_popcnt_u64(unsigned long long __A) { return __builtin_popcountll(__A); @@ -48,5 +54,6 @@ _mm_popcnt_u64(unsigned long long __A) #endif /* __x86_64__ */ #undef __DEFAULT_FN_ATTRS +#undef __DEFAULT_FN_ATTRS_CONSTEXPR #endif /* __POPCNTINTRIN_H */ diff --git a/clang/test/CodeGen/popcnt-builtins.c b/clang/test/CodeGen/popcnt-builtins.c index d9e7c5238513..40b786275e93 100644 --- a/clang/test/CodeGen/popcnt-builtins.c +++ b/clang/test/CodeGen/popcnt-builtins.c @@ -1,6 +1,7 @@ -// RUN: %clang_cc1 -ffreestanding %s -triple=x86_64-apple-darwin -target-feature +popcnt -emit-llvm -o - | FileCheck %s --check-prefixes=CHECK,CHECK-POPCNT -// RUN: %clang_cc1 -ffreestanding %s -triple=x86_64-apple-darwin -emit-llvm -o - | FileCheck %s - +// RUN: %clang_cc1 -x c -ffreestanding %s -triple=x86_64-apple-darwin -target-feature +popcnt -emit-llvm -o - | FileCheck %s --check-prefixes=CHECK,CHECK-POPCNT +// RUN: %clang_cc1 -x c++ -std=c++11 -ffreestanding %s -triple=x86_64-apple-darwin -target-feature +popcnt -emit-llvm -o - | FileCheck %s --check-prefixes=CHECK,CHECK-POPCNT +// RUN: %clang_cc1 -x c -ffreestanding %s -triple=x86_64-apple-darwin -emit-llvm -o - | FileCheck %s +// RUN: %clang_cc1 -x c++ -std=c++11 -ffreestanding %s -triple=x86_64-apple-darwin -emit-llvm -o - | FileCheck %s #include <x86intrin.h> @@ -39,3 +40,16 @@ long long test__popcntq(unsigned long long __X) { return __popcntq(__X); } #endif + +// Test constexpr handling. +#if defined(__cplusplus) && (__cplusplus >= 201103L) +#if defined(__POPCNT__) +char ctpop32_0[_mm_popcnt_u32(0x00000000) == 0 ? 1 : -1]; +char ctpop32_1[_mm_popcnt_u32(0x000000F0) == 4 ? 1 : -1]; + +#ifdef __x86_64__ +char ctpop64_0[_mm_popcnt_u64(0x0000000000000000ULL) == 0 ? 1 : -1]; +char ctpop64_1[_mm_popcnt_u64(0xF000000000000001ULL) == 5 ? 1 : -1]; +#endif +#endif +#endif _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
