https://github.com/pogo59 created https://github.com/llvm/llvm-project/pull/78613
These are largely copy-pasted from the corresponding function descriptions. Updated _rdtsc definition because it was just plain wrong. >From e4c9272ee9cbb918347a23d2dce14c9c12765009 Mon Sep 17 00:00:00 2001 From: Paul Robinson <paul.robin...@sony.com> Date: Thu, 18 Jan 2024 10:50:21 -0800 Subject: [PATCH] [Headers][X86] Add macro descriptions to ia32intrin.h These are largely copy-pasted from the corresponding function descriptions. Updated _rdtsc definition because it was just plain wrong. --- clang/lib/Headers/ia32intrin.h | 253 ++++++++++++++++++++++++++++++++- 1 file changed, 249 insertions(+), 4 deletions(-) diff --git a/clang/lib/Headers/ia32intrin.h b/clang/lib/Headers/ia32intrin.h index 7d5fede61ce859..5d8d02ea14200f 100644 --- a/clang/lib/Headers/ia32intrin.h +++ b/clang/lib/Headers/ia32intrin.h @@ -88,7 +88,38 @@ _bswap(int __A) { return (int)__builtin_bswap32((unsigned int)__A); } +/// Find the first set bit starting from the lsb. Result is undefined if +/// input is 0. +/// +/// \headerfile <x86intrin.h> +/// +/// \code +/// int _bit_scan_forward(int A); +/// \endcode +/// +/// This intrinsic corresponds to the \c BSF instruction or the +/// \c TZCNT instruction. +/// +/// \param A +/// A 32-bit integer operand. +/// \returns A 32-bit integer containing the bit number. #define _bit_scan_forward(A) __bsfd((A)) + +/// Find the first set bit starting from the msb. Result is undefined if +/// input is 0. +/// +/// \headerfile <x86intrin.h> +/// +/// \code +/// int _bit_scan_reverse(int A); +/// \endcode +/// +/// This intrinsic corresponds to the \c BSR instruction or the +/// \c LZCNT instruction and an \c XOR. +/// +/// \param A +/// A 32-bit integer operand. +/// \returns A 32-bit integer containing the bit number. #define _bit_scan_reverse(A) __bsrd((A)) #ifdef __x86_64__ @@ -139,8 +170,22 @@ __bswapq(long long __A) { return (long long)__builtin_bswap64((unsigned long long)__A); } +/// Swaps the bytes in the input. Converting little endian to big endian or +/// vice versa. +/// +/// \headerfile <x86intrin.h> +/// +/// \code +/// long long _bswap64(long long A); +/// \endcode +/// +/// This intrinsic corresponds to the \c BSWAP instruction. +/// +/// \param A +/// A 64-bit integer operand. +/// \returns A 64-bit integer containing the swapped bytes. #define _bswap64(A) __bswapq((A)) -#endif +#endif /* __x86_64__ */ /// Counts the number of bits in the source operand having a value of 1. /// @@ -159,6 +204,21 @@ __popcntd(unsigned int __A) return __builtin_popcount(__A); } +/// Counts the number of bits in the source operand having a value of 1. +/// +/// \headerfile <x86intrin.h> +/// +/// \code +/// int _popcnt32(int A); +/// \endcode +/// +/// This intrinsic corresponds to the \c POPCNT instruction or a +/// a sequence of arithmetic and logic ops to calculate it. +/// +/// \param A +/// An unsigned 32-bit integer operand. +/// \returns A 32-bit integer containing the number of bits with value 1 in the +/// source operand. #define _popcnt32(A) __popcntd((A)) #ifdef __x86_64__ @@ -179,6 +239,21 @@ __popcntq(unsigned long long __A) return __builtin_popcountll(__A); } +/// Counts the number of bits in the source operand having a value of 1. +/// +/// \headerfile <x86intrin.h> +/// +/// \code +/// long long _popcnt64(unsigned long long A); +/// \endcode +/// +/// This intrinsic corresponds to the \c POPCNT instruction or a +/// a sequence of arithmetic and logic ops to calculate it. +/// +/// \param A +/// An unsigned 64-bit integer operand. +/// \returns A 64-bit integer containing the number of bits with value 1 in the +/// source operand. #define _popcnt64(A) __popcntq((A)) #endif /* __x86_64__ */ @@ -416,8 +491,37 @@ __rdtscp(unsigned int *__A) { return __builtin_ia32_rdtscp(__A); } -#define _rdtsc() __rdtsc() +/// Reads the processor's time stamp counter and the \c IA32_TSC_AUX MSR +/// \c (0xc0000103). +/// +/// \headerfile <x86intrin.h> +/// +/// \code +/// unsigned long long _rdtsc(unsigned int *A); +/// \endcode +/// +/// This intrinsic corresponds to the \c RDTSCP instruction. +/// +/// \param A +/// Address of where to store the 32-bit \c IA32_TSC_AUX value. +/// \returns The 64-bit value of the time stamp counter. +#define _rdtsc(A) __rdtscp(A) +/// Reads the specified performance monitoring counter. Refer to your +/// processor's documentation to determine which performance counters are +/// supported. +/// +/// \headerfile <x86intrin.h> +/// +/// \code +/// unsigned long long _rdpmc(int A); +/// \endcode +/// +/// This intrinsic corresponds to the \c RDPMC instruction. +/// +/// \param A +/// The performance counter to read. +/// \returns The 64-bit value read from the performance counter. #define _rdpmc(A) __rdpmc(A) static __inline__ void __DEFAULT_FN_ATTRS @@ -575,18 +679,159 @@ __rorq(unsigned long long __X, int __C) { /* These are already provided as builtins for MSVC. */ /* Select the correct function based on the size of long. */ #ifdef __LP64__ +/// Rotates a 64-bit value to the left by the specified number of bits. +/// This operation is undefined if the number of bits exceeds the size of +/// the value. +/// +/// \headerfile <x86intrin.h> +/// +/// \code +/// unsigned long long _lrotl(unsigned long long a, int b); +/// \endcode +/// +/// This intrinsic corresponds to the \c ROL instruction. +/// +/// \param a +/// The unsigned 64-bit value to be rotated. +/// \param b +/// The number of bits to rotate the value. +/// \returns The rotated value. #define _lrotl(a,b) __rolq((a), (b)) + +/// Rotates a 64-bit value to the right by the specified number of bits. +/// This operation is undefined if the number of bits exceeds the size of +/// the value. +/// +/// \headerfile <x86intrin.h> +/// +/// \code +/// unsigned long long _lrotr(unsigned long long a, int b); +/// \endcode +/// +/// This intrinsic corresponds to the \c ROR instruction. +/// +/// \param a +/// The unsigned 64-bit value to be rotated. +/// \param b +/// The number of bits to rotate the value. +/// \returns The rotated value. #define _lrotr(a,b) __rorq((a), (b)) -#else +#else // __LP64__ +/// Rotates a 32-bit value to the left by the specified number of bits. +/// This operation is undefined if the number of bits exceeds the size of +/// the value. +/// +/// \headerfile <x86intrin.h> +/// +/// \code +/// unsigned int _lrotl(unsigned int a, int b); +/// \endcode +/// +/// This intrinsic corresponds to the \c ROL instruction. +/// +/// \param a +/// The unsigned 32-bit value to be rotated. +/// \param b +/// The number of bits to rotate the value. +/// \returns The rotated value. #define _lrotl(a,b) __rold((a), (b)) + +/// Rotates a 32-bit value to the right by the specified number of bits. +/// This operation is undefined if the number of bits exceeds the size of +/// the value. +/// +/// \headerfile <x86intrin.h> +/// +/// \code +/// unsigned int _lrotr(unsigned int a, int b); +/// \endcode +/// +/// This intrinsic corresponds to the \c ROR instruction. +/// +/// \param a +/// The unsigned 32-bit value to be rotated. +/// \param b +/// The number of bits to rotate the value. +/// \returns The rotated value. #define _lrotr(a,b) __rord((a), (b)) -#endif +#endif // __LP64__ + +/// Rotates a 32-bit value to the left by the specified number of bits. +/// This operation is undefined if the number of bits exceeds the size of +/// the value. +/// +/// \headerfile <x86intrin.h> +/// +/// \code +/// unsigned int _rotl(unsigned int a, int b); +/// \endcode +/// +/// This intrinsic corresponds to the \c ROL instruction. +/// +/// \param a +/// The unsigned 32-bit value to be rotated. +/// \param b +/// The number of bits to rotate the value. +/// \returns The rotated value. #define _rotl(a,b) __rold((a), (b)) + +/// Rotates a 32-bit value to the right by the specified number of bits. +/// This operation is undefined if the number of bits exceeds the size of +/// the value. +/// +/// \headerfile <x86intrin.h> +/// +/// \code +/// unsigned int _rotr(unsigned int a, int b); +/// \endcode +/// +/// This intrinsic corresponds to the \c ROR instruction. +/// +/// \param a +/// The unsigned 32-bit value to be rotated. +/// \param b +/// The number of bits to rotate the value. +/// \returns The rotated value. #define _rotr(a,b) __rord((a), (b)) #endif // _MSC_VER /* These are not builtins so need to be provided in all modes. */ +/// Rotates a 16-bit value to the left by the specified number of bits. +/// This operation is undefined if the number of bits exceeds the size of +/// the value. +/// +/// \headerfile <x86intrin.h> +/// +/// \code +/// unsigned short _rotwl(unsigned short a, int b); +/// \endcode +/// +/// This intrinsic corresponds to the \c ROL instruction. +/// +/// \param a +/// The unsigned 16-bit value to be rotated. +/// \param b +/// The number of bits to rotate the value. +/// \returns The rotated value. #define _rotwl(a,b) __rolw((a), (b)) + +/// Rotates a 16-bit value to the right by the specified number of bits. +/// This operation is undefined if the number of bits exceeds the size of +/// the value. +/// +/// \headerfile <x86intrin.h> +/// +/// \code +/// unsigned short _rotwr(unsigned short a, int b); +/// \endcode +/// +/// This intrinsic corresponds to the \c ROR instruction. +/// +/// \param a +/// The unsigned 16-bit value to be rotated. +/// \param b +/// The number of bits to rotate the value. +/// \returns The rotated value. #define _rotwr(a,b) __rorw((a), (b)) #undef __DEFAULT_FN_ATTRS _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits