From 1fd8c163a83d96ace1ff78fa6bac7aee084f6f77 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Fri, 5 Mar 2021 06:24:52 -0800 Subject: x86-64: Add ifunc-avx2.h functions with 256-bit EVEX Update ifunc-avx2.h, strchr.c, strcmp.c, strncmp.c and wcsnlen.c to select the function optimized with 256-bit EVEX instructions using YMM16-YMM31 registers to avoid RTM abort with usable AVX512VL, AVX512BW and BMI2 since VZEROUPPER isn't needed at function exit. For strcmp/strncmp, prefer AVX2 strcmp/strncmp if Prefer_AVX2_STRCMP is set. --- sysdeps/x86_64/multiarch/memchr-evex.S | 381 +++++++++++++++++++++++++++++++++ 1 file changed, 381 insertions(+) create mode 100644 sysdeps/x86_64/multiarch/memchr-evex.S (limited to 'sysdeps/x86_64/multiarch/memchr-evex.S') diff --git a/sysdeps/x86_64/multiarch/memchr-evex.S b/sysdeps/x86_64/multiarch/memchr-evex.S new file mode 100644 index 0000000000..6dd5d67b90 --- /dev/null +++ b/sysdeps/x86_64/multiarch/memchr-evex.S @@ -0,0 +1,381 @@ +/* memchr/wmemchr optimized with 256-bit EVEX instructions. + Copyright (C) 2021 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#if IS_IN (libc) + +# include + +# ifndef MEMCHR +# define MEMCHR __memchr_evex +# endif + +# ifdef USE_AS_WMEMCHR +# define VPBROADCAST vpbroadcastd +# define VPCMP vpcmpd +# define SHIFT_REG r8d +# else +# define VPBROADCAST vpbroadcastb +# define VPCMP vpcmpb +# define SHIFT_REG ecx +# endif + +# define XMMMATCH xmm16 +# define YMMMATCH ymm16 +# define YMM1 ymm17 +# define YMM2 ymm18 +# define YMM3 ymm19 +# define YMM4 ymm20 +# define YMM5 ymm21 +# define YMM6 ymm22 + +# define VEC_SIZE 32 + + .section .text.evex,"ax",@progbits +ENTRY (MEMCHR) +# ifndef USE_AS_RAWMEMCHR + /* Check for zero length. */ + test %RDX_LP, %RDX_LP + jz L(zero) +# endif + movl %edi, %ecx +# ifdef USE_AS_WMEMCHR + shl $2, %RDX_LP +# else +# ifdef __ILP32__ + /* Clear the upper 32 bits. */ + movl %edx, %edx +# endif +# endif + /* Broadcast CHAR to YMMMATCH. */ + VPBROADCAST %esi, %YMMMATCH + /* Check if we may cross page boundary with one vector load. */ + andl $(2 * VEC_SIZE - 1), %ecx + cmpl $VEC_SIZE, %ecx + ja L(cros_page_boundary) + + /* Check the first VEC_SIZE bytes. */ + VPCMP $0, (%rdi), %YMMMATCH, %k1 + kmovd %k1, %eax + testl %eax, %eax + +# ifndef USE_AS_RAWMEMCHR + jnz L(first_vec_x0_check) + /* Adjust length and check the end of data. */ + subq $VEC_SIZE, %rdx + jbe L(zero) +# else + jnz L(first_vec_x0) +# endif + + /* Align data for aligned loads in the loop. */ + addq $VEC_SIZE, %rdi + andl $(VEC_SIZE - 1), %ecx + andq $-VEC_SIZE, %rdi + +# ifndef USE_AS_RAWMEMCHR + /* Adjust length. */ + addq %rcx, %rdx + + subq $(VEC_SIZE * 4), %rdx + jbe L(last_4x_vec_or_less) +# endif + jmp L(more_4x_vec) + + .p2align 4 +L(cros_page_boundary): + andl $(VEC_SIZE - 1), %ecx +# ifdef USE_AS_WMEMCHR + /* NB: Divide shift count by 4 since each bit in K1 represent 4 + bytes. */ + movl %ecx, %SHIFT_REG + sarl $2, %SHIFT_REG +# endif + andq $-VEC_SIZE, %rdi + VPCMP $0, (%rdi), %YMMMATCH, %k1 + kmovd %k1, %eax + /* Remove the leading bytes. */ + sarxl %SHIFT_REG, %eax, %eax + testl %eax, %eax + jz L(aligned_more) + tzcntl %eax, %eax +# ifdef USE_AS_WMEMCHR + /* NB: Multiply wchar_t count by 4 to get the number of bytes. */ + sall $2, %eax +# endif +# ifndef USE_AS_RAWMEMCHR + /* Check the end of data. */ + cmpq %rax, %rdx + jbe L(zero) +# endif + addq %rdi, %rax + addq %rcx, %rax + ret + + .p2align 4 +L(aligned_more): +# ifndef USE_AS_RAWMEMCHR + /* Calculate "rdx + rcx - VEC_SIZE" with "rdx - (VEC_SIZE - rcx)" + instead of "(rdx + rcx) - VEC_SIZE" to void possible addition + overflow. */ + negq %rcx + addq $VEC_SIZE, %rcx + + /* Check the end of data. */ + subq %rcx, %rdx + jbe L(zero) +# endif + + addq $VEC_SIZE, %rdi + +# ifndef USE_AS_RAWMEMCHR + subq $(VEC_SIZE * 4), %rdx + jbe L(last_4x_vec_or_less) +# endif + +L(more_4x_vec): + /* Check the first 4 * VEC_SIZE. Only one VEC_SIZE at a time + since data is only aligned to VEC_SIZE. */ + VPCMP $0, (%rdi), %YMMMATCH, %k1 + kmovd %k1, %eax + testl %eax, %eax + jnz L(first_vec_x0) + + VPCMP $0, VEC_SIZE(%rdi), %YMMMATCH, %k1 + kmovd %k1, %eax + testl %eax, %eax + jnz L(first_vec_x1) + + VPCMP $0, (VEC_SIZE * 2)(%rdi), %YMMMATCH, %k1 + kmovd %k1, %eax + testl %eax, %eax + jnz L(first_vec_x2) + + VPCMP $0, (VEC_SIZE * 3)(%rdi), %YMMMATCH, %k1 + kmovd %k1, %eax + testl %eax, %eax + jnz L(first_vec_x3) + + addq $(VEC_SIZE * 4), %rdi + +# ifndef USE_AS_RAWMEMCHR + subq $(VEC_SIZE * 4), %rdx + jbe L(last_4x_vec_or_less) +# endif + + /* Align data to 4 * VEC_SIZE. */ + movq %rdi, %rcx + andl $(4 * VEC_SIZE - 1), %ecx + andq $-(4 * VEC_SIZE), %rdi + +# ifndef USE_AS_RAWMEMCHR + /* Adjust length. */ + addq %rcx, %rdx +# endif + + .p2align 4 +L(loop_4x_vec): + /* Compare 4 * VEC at a time forward. */ + VPCMP $0, (%rdi), %YMMMATCH, %k1 + VPCMP $0, VEC_SIZE(%rdi), %YMMMATCH, %k2 + kord %k1, %k2, %k5 + VPCMP $0, (VEC_SIZE * 2)(%rdi), %YMMMATCH, %k3 + VPCMP $0, (VEC_SIZE * 3)(%rdi), %YMMMATCH, %k4 + + kord %k3, %k4, %k6 + kortestd %k5, %k6 + jnz L(4x_vec_end) + + addq $(VEC_SIZE * 4), %rdi + +# ifdef USE_AS_RAWMEMCHR + jmp L(loop_4x_vec) +# else + subq $(VEC_SIZE * 4), %rdx + ja L(loop_4x_vec) + +L(last_4x_vec_or_less): + /* Less than 4 * VEC and aligned to VEC_SIZE. */ + addl $(VEC_SIZE * 2), %edx + jle L(last_2x_vec) + + VPCMP $0, (%rdi), %YMMMATCH, %k1 + kmovd %k1, %eax + testl %eax, %eax + jnz L(first_vec_x0) + + VPCMP $0, VEC_SIZE(%rdi), %YMMMATCH, %k1 + kmovd %k1, %eax + testl %eax, %eax + jnz L(first_vec_x1) + + VPCMP $0, (VEC_SIZE * 2)(%rdi), %YMMMATCH, %k1 + kmovd %k1, %eax + testl %eax, %eax + + jnz L(first_vec_x2_check) + subl $VEC_SIZE, %edx + jle L(zero) + + VPCMP $0, (VEC_SIZE * 3)(%rdi), %YMMMATCH, %k1 + kmovd %k1, %eax + testl %eax, %eax + + jnz L(first_vec_x3_check) + xorl %eax, %eax + ret + + .p2align 4 +L(last_2x_vec): + addl $(VEC_SIZE * 2), %edx + VPCMP $0, (%rdi), %YMMMATCH, %k1 + kmovd %k1, %eax + testl %eax, %eax + + jnz L(first_vec_x0_check) + subl $VEC_SIZE, %edx + jle L(zero) + + VPCMP $0, VEC_SIZE(%rdi), %YMMMATCH, %k1 + kmovd %k1, %eax + testl %eax, %eax + jnz L(first_vec_x1_check) + xorl %eax, %eax + ret + + .p2align 4 +L(first_vec_x0_check): + tzcntl %eax, %eax +# ifdef USE_AS_WMEMCHR + /* NB: Multiply wchar_t count by 4 to get the number of bytes. */ + sall $2, %eax +# endif + /* Check the end of data. */ + cmpq %rax, %rdx + jbe L(zero) + addq %rdi, %rax + ret + + .p2align 4 +L(first_vec_x1_check): + tzcntl %eax, %eax +# ifdef USE_AS_WMEMCHR + /* NB: Multiply wchar_t count by 4 to get the number of bytes. */ + sall $2, %eax +# endif + /* Check the end of data. */ + cmpq %rax, %rdx + jbe L(zero) + addq $VEC_SIZE, %rax + addq %rdi, %rax + ret + + .p2align 4 +L(first_vec_x2_check): + tzcntl %eax, %eax +# ifdef USE_AS_WMEMCHR + /* NB: Multiply wchar_t count by 4 to get the number of bytes. */ + sall $2, %eax +# endif + /* Check the end of data. */ + cmpq %rax, %rdx + jbe L(zero) + addq $(VEC_SIZE * 2), %rax + addq %rdi, %rax + ret + + .p2align 4 +L(first_vec_x3_check): + tzcntl %eax, %eax +# ifdef USE_AS_WMEMCHR + /* NB: Multiply wchar_t count by 4 to get the number of bytes. */ + sall $2, %eax +# endif + /* Check the end of data. */ + cmpq %rax, %rdx + jbe L(zero) + addq $(VEC_SIZE * 3), %rax + addq %rdi, %rax + ret + + .p2align 4 +L(zero): + xorl %eax, %eax + ret +# endif + + .p2align 4 +L(first_vec_x0): + tzcntl %eax, %eax +# ifdef USE_AS_WMEMCHR + /* NB: Multiply wchar_t count by 4 to get the number of bytes. */ + leaq (%rdi, %rax, 4), %rax +# else + addq %rdi, %rax +# endif + ret + + .p2align 4 +L(first_vec_x1): + tzcntl %eax, %eax +# ifdef USE_AS_WMEMCHR + /* NB: Multiply wchar_t count by 4 to get the number of bytes. */ + leaq VEC_SIZE(%rdi, %rax, 4), %rax +# else + addq $VEC_SIZE, %rax + addq %rdi, %rax +# endif + ret + + .p2align 4 +L(first_vec_x2): + tzcntl %eax, %eax +# ifdef USE_AS_WMEMCHR + /* NB: Multiply wchar_t count by 4 to get the number of bytes. */ + leaq (VEC_SIZE * 2)(%rdi, %rax, 4), %rax +# else + addq $(VEC_SIZE * 2), %rax + addq %rdi, %rax +# endif + ret + + .p2align 4 +L(4x_vec_end): + kmovd %k1, %eax + testl %eax, %eax + jnz L(first_vec_x0) + kmovd %k2, %eax + testl %eax, %eax + jnz L(first_vec_x1) + kmovd %k3, %eax + testl %eax, %eax + jnz L(first_vec_x2) + kmovd %k4, %eax + testl %eax, %eax +L(first_vec_x3): + tzcntl %eax, %eax +# ifdef USE_AS_WMEMCHR + /* NB: Multiply wchar_t count by 4 to get the number of bytes. */ + leaq (VEC_SIZE * 3)(%rdi, %rax, 4), %rax +# else + addq $(VEC_SIZE * 3), %rax + addq %rdi, %rax +# endif + ret + +END (MEMCHR) +#endif -- cgit 1.4.1