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x86: Unifies 'strlen-evex' and 'strlen-evex512' implementations.
This commit uses a common implementation 'strlen-evex-base.S' for both 'strlen-evex' and 'strlen-evex512' The motivation is to reduce the number of implementations to maintain. This incidentally gives a small performance improvement. All tests pass on x86. Benchmarks were taken on SKX. https://www.intel.com/content/www/us/en/products/sku/123613/intel-core-i97900x-xseries-processor-13-75m-cache-up-to-4-30-ghz/specifications.html Geometric mean for strlen-evex512 over all benchmarks (N=10) was (new/old) 0.939 Geometric mean for wcslen-evex512 over all benchmarks (N=10) was (new/old) 0.965 Code Size Changes: strlen-evex512.S : +24 bytes wcslen-evex512.S : +54 bytes Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
This commit is contained in:
Matthew Sterrett
Noah Goldstein
parent
442983319b
commit
e957308723
5 changed files with 450 additions and 483 deletions
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@ -1,5 +1,5 @@
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/* Placeholder function, not used by any processor at the moment.
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Copyright (C) 2022-2023 Free Software Foundation, Inc.
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/* strlen/wcslen optimized with 256/512-bit EVEX instructions.
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Copyright (C) 2021-2023 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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@ -16,7 +16,6 @@
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License along with the GNU C Library; if not, see
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<https://www.gnu.org/licenses/>. */
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/* UNUSED. Exists purely as reference implementation. */
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#include <isa-level.h>
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@ -26,272 +25,211 @@
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# ifdef USE_AS_WCSLEN
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# define VPCMPEQ vpcmpeqd
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# define VPCMPNEQ vpcmpneqd
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# define VPTESTN vptestnmd
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# define VPTEST vptestmd
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# define VPMINU vpminud
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# define CHAR_SIZE 4
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# define CHAR_SIZE_SHIFT_REG(reg) sar $2, %reg
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# else
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# define VPCMPEQ vpcmpeqb
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# define VPCMPNEQ vpcmpneqb
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# define VPTESTN vptestnmb
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# define VPTEST vptestmb
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# define VPMINU vpminub
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# define CHAR_SIZE 1
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# define CHAR_SIZE_SHIFT_REG(reg)
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# define REG_WIDTH VEC_SIZE
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# endif
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# define PAGE_SIZE 4096
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# define CHAR_PER_VEC (VEC_SIZE / CHAR_SIZE)
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.section SECTION(.text),"ax",@progbits
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/* Aligning entry point to 64 byte, provides better performance for
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one vector length string. */
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ENTRY_P2ALIGN (STRLEN, 6)
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# ifdef USE_AS_STRNLEN
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/* Check zero length. */
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test %RSI_LP, %RSI_LP
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jz L(ret_max)
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# ifdef __ILP32__
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/* Clear the upper 32 bits. */
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movl %esi, %esi
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# endif
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# include "reg-macros.h"
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# if CHAR_PER_VEC == 64
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# define TAIL_RETURN_LBL first_vec_x2
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# define TAIL_RETURN_OFFSET (CHAR_PER_VEC * 2)
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# define FALLTHROUGH_RETURN_LBL first_vec_x3
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# define FALLTHROUGH_RETURN_OFFSET (CHAR_PER_VEC * 3)
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# else
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# define TAIL_RETURN_LBL first_vec_x3
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# define TAIL_RETURN_OFFSET (CHAR_PER_VEC * 3)
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# define FALLTHROUGH_RETURN_LBL first_vec_x2
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# define FALLTHROUGH_RETURN_OFFSET (CHAR_PER_VEC * 2)
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# endif
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movl %edi, %eax
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vpxorq %VMM_128(0), %VMM_128(0), %VMM_128(0)
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sall $20, %eax
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cmpl $((PAGE_SIZE - VEC_SIZE) << 20), %eax
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ja L(page_cross)
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# define XZERO VMM_128(0)
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# define VZERO VMM(0)
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# define PAGE_SIZE 4096
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/* Compare [w]char for null, mask bit will be set for match. */
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VPCMPEQ (%rdi), %VMM(0), %k0
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# ifdef USE_AS_STRNLEN
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KMOV %k0, %VRCX
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/* Store max length in rax. */
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mov %rsi, %rax
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/* If rcx is 0, rax will have max length. We can not use VRCX
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and VRAX here for evex256 because, upper 32 bits may be
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undefined for ecx and eax. */
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bsfq %rcx, %rax
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cmp $CHAR_PER_VEC, %rax
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ja L(align_more)
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cmpq %rax, %rsi
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cmovb %esi, %eax
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# else
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.section SECTION(.text), "ax", @progbits
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ENTRY_P2ALIGN(STRLEN, 6)
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movl %edi, %eax
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vpxorq %XZERO, %XZERO, %XZERO
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andl $(PAGE_SIZE - 1), %eax
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cmpl $(PAGE_SIZE - VEC_SIZE), %eax
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ja L(cross_page_boundary)
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/* Check the first VEC_SIZE bytes. Each bit in K0 represents a
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null byte. */
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VPCMPEQ (%rdi), %VZERO, %k0
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KMOV %k0, %VRAX
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test %VRAX, %VRAX
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jz L(align_more)
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jz L(aligned_more)
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bsf %VRAX, %VRAX
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# endif
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ret
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/* At this point vector max length reached. */
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# ifdef USE_AS_STRNLEN
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.p2align 4,,3
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L(ret_max):
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movq %rsi, %rax
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.p2align 4,, 8
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L(first_vec_x4):
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bsf %VRAX, %VRAX
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subl %ecx, %edi
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CHAR_SIZE_SHIFT_REG (edi)
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leal (CHAR_PER_VEC * 4)(%rdi, %rax), %eax
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ret
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/* Aligned more for strnlen compares remaining length vs 2 *
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CHAR_PER_VEC, 4 * CHAR_PER_VEC, and 8 * CHAR_PER_VEC before
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going to the loop. */
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.p2align 4,, 10
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L(aligned_more):
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movq %rdi, %rcx
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andq $(VEC_SIZE * -1), %rdi
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L(cross_page_continue):
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/* Remaining length >= 2 * CHAR_PER_VEC so do VEC0/VEC1 without
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rechecking bounds. */
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VPCMPEQ (VEC_SIZE * 1)(%rdi), %VZERO, %k0
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KMOV %k0, %VRAX
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test %VRAX, %VRAX
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jnz L(first_vec_x1)
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VPCMPEQ (VEC_SIZE * 2)(%rdi), %VZERO, %k0
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KMOV %k0, %VRAX
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test %VRAX, %VRAX
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jnz L(first_vec_x2)
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VPCMPEQ (VEC_SIZE * 3)(%rdi), %VZERO, %k0
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KMOV %k0, %VRAX
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test %VRAX, %VRAX
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jnz L(first_vec_x3)
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VPCMPEQ (VEC_SIZE * 4)(%rdi), %VZERO, %k0
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KMOV %k0, %VRAX
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test %VRAX, %VRAX
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jnz L(first_vec_x4)
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subq $(VEC_SIZE * -1), %rdi
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# if CHAR_PER_VEC == 64
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/* No partial register stalls on processors that we use evex512
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on and this saves code size. */
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xorb %dil, %dil
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# else
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andq $-(VEC_SIZE * 4), %rdi
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# endif
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L(align_more):
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mov %rdi, %rax
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/* Align rax to VEC_SIZE. */
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andq $-VEC_SIZE, %rax
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# ifdef USE_AS_STRNLEN
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movq %rdi, %rdx
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subq %rax, %rdx
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# ifdef USE_AS_WCSLEN
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shr $2, %VRDX
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# endif
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/* At this point rdx contains [w]chars already compared. */
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leaq -CHAR_PER_VEC(%rsi, %rdx), %rdx
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/* At this point rdx contains number of w[char] needs to go.
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Now onwards rdx will keep decrementing with each compare. */
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# endif
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/* Loop unroll 4 times for 4 vector loop. */
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VPCMPEQ VEC_SIZE(%rax), %VMM(0), %k0
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subq $-VEC_SIZE, %rax
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KMOV %k0, %VRCX
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test %VRCX, %VRCX
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jnz L(ret_vec_x1)
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# ifdef USE_AS_STRNLEN
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subq $CHAR_PER_VEC, %rdx
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jbe L(ret_max)
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# endif
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VPCMPEQ VEC_SIZE(%rax), %VMM(0), %k0
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KMOV %k0, %VRCX
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test %VRCX, %VRCX
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jnz L(ret_vec_x2)
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# ifdef USE_AS_STRNLEN
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subq $CHAR_PER_VEC, %rdx
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jbe L(ret_max)
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# endif
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VPCMPEQ (VEC_SIZE * 2)(%rax), %VMM(0), %k0
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KMOV %k0, %VRCX
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test %VRCX, %VRCX
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jnz L(ret_vec_x3)
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# ifdef USE_AS_STRNLEN
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subq $CHAR_PER_VEC, %rdx
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jbe L(ret_max)
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# endif
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VPCMPEQ (VEC_SIZE * 3)(%rax), %VMM(0), %k0
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KMOV %k0, %VRCX
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test %VRCX, %VRCX
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jnz L(ret_vec_x4)
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# ifdef USE_AS_STRNLEN
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subq $CHAR_PER_VEC, %rdx
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jbe L(ret_max)
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/* Save pointer before 4 x VEC_SIZE alignment. */
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movq %rax, %rcx
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# endif
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/* Align address to VEC_SIZE * 4 for loop. */
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andq $-(VEC_SIZE * 4), %rax
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# ifdef USE_AS_STRNLEN
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subq %rax, %rcx
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# ifdef USE_AS_WCSLEN
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shr $2, %VRCX
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# endif
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/* rcx contains number of [w]char will be recompared due to
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alignment fixes. rdx must be incremented by rcx to offset
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alignment adjustment. */
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addq %rcx, %rdx
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/* Need jump as we don't want to add/subtract rdx for first
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iteration of 4 x VEC_SIZE aligned loop. */
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# endif
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.p2align 4,,11
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L(loop):
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/* VPMINU and VPCMP combination provide better performance as
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compared to alternative combinations. */
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VMOVA (VEC_SIZE * 4)(%rax), %VMM(1)
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VPMINU (VEC_SIZE * 5)(%rax), %VMM(1), %VMM(2)
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VMOVA (VEC_SIZE * 6)(%rax), %VMM(3)
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VPMINU (VEC_SIZE * 7)(%rax), %VMM(3), %VMM(4)
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/* Compare 4 * VEC at a time forward. */
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.p2align 4
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L(loop_4x_vec):
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VMOVA (VEC_SIZE * 4)(%rdi), %VMM(1)
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VPMINU (VEC_SIZE * 5)(%rdi), %VMM(1), %VMM(2)
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VMOVA (VEC_SIZE * 6)(%rdi), %VMM(3)
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VPMINU (VEC_SIZE * 7)(%rdi), %VMM(3), %VMM(4)
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VPTESTN %VMM(2), %VMM(2), %k0
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VPTESTN %VMM(4), %VMM(4), %k1
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VPTESTN %VMM(4), %VMM(4), %k2
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subq $-(VEC_SIZE * 4), %rax
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KORTEST %k0, %k1
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subq $-(VEC_SIZE * 4), %rdi
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KORTEST %k0, %k2
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jz L(loop_4x_vec)
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# ifndef USE_AS_STRNLEN
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jz L(loop)
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VPTESTN %VMM(1), %VMM(1), %k1
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KMOV %k1, %VRAX
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test %VRAX, %VRAX
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jnz L(first_vec_x0)
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KMOV %k0, %VRAX
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test %VRAX, %VRAX
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jnz L(first_vec_x1)
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VPTESTN %VMM(3), %VMM(3), %k0
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# if CHAR_PER_VEC == 64
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KMOV %k0, %VRAX
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test %VRAX, %VRAX
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jnz L(first_vec_x2)
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KMOV %k2, %VRAX
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# else
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jnz L(loopend)
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subq $(CHAR_PER_VEC * 4), %rdx
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ja L(loop)
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mov %rsi, %rax
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ret
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/* We can only combine last 2x VEC masks if CHAR_PER_VEC <= 32. */
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kmovd %k2, %edx
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kmovd %k0, %eax
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salq $CHAR_PER_VEC, %rdx
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orq %rdx, %rax
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# endif
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L(loopend):
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/* first_vec_x3 for strlen-ZMM and first_vec_x2 for strlen-YMM. */
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.p2align 4,, 2
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L(FALLTHROUGH_RETURN_LBL):
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bsfq %rax, %rax
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subq %rcx, %rdi
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CHAR_SIZE_SHIFT_REG (rdi)
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leaq (FALLTHROUGH_RETURN_OFFSET)(%rdi, %rax), %rax
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ret
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VPTESTN %VMM(1), %VMM(1), %k2
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KMOV %k2, %VRCX
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test %VRCX, %VRCX
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jnz L(ret_vec_x1)
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.p2align 4,, 8
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L(first_vec_x0):
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bsf %VRAX, %VRAX
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sub %rcx, %rdi
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CHAR_SIZE_SHIFT_REG (rdi)
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addq %rdi, %rax
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ret
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KMOV %k0, %VRCX
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/* At this point, if k0 is non zero, null char must be in the
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second vector. */
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test %VRCX, %VRCX
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jnz L(ret_vec_x2)
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.p2align 4,, 10
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L(first_vec_x1):
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bsf %VRAX, %VRAX
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sub %rcx, %rdi
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CHAR_SIZE_SHIFT_REG (rdi)
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leaq (CHAR_PER_VEC)(%rdi, %rax), %rax
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ret
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VPTESTN %VMM(3), %VMM(3), %k3
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KMOV %k3, %VRCX
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test %VRCX, %VRCX
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jnz L(ret_vec_x3)
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/* At this point null [w]char must be in the fourth vector so no
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need to check. */
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KMOV %k1, %VRCX
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.p2align 4,, 10
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/* first_vec_x2 for strlen-ZMM and first_vec_x3 for strlen-YMM. */
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L(TAIL_RETURN_LBL):
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bsf %VRAX, %VRAX
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sub %VRCX, %VRDI
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CHAR_SIZE_SHIFT_REG (VRDI)
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lea (TAIL_RETURN_OFFSET)(%rdi, %rax), %VRAX
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ret
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/* Fourth, third, second vector terminating are pretty much
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same, implemented this way to avoid branching and reuse code
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from pre loop exit condition. */
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L(ret_vec_x4):
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bsf %VRCX, %VRCX
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subq %rdi, %rax
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.p2align 4,, 8
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L(cross_page_boundary):
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movq %rdi, %rcx
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/* Align data to VEC_SIZE. */
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andq $-VEC_SIZE, %rdi
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VPCMPEQ (%rdi), %VZERO, %k0
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KMOV %k0, %VRAX
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# ifdef USE_AS_WCSLEN
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subq $-(VEC_SIZE * 3), %rax
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shrq $2, %rax
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addq %rcx, %rax
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movl %ecx, %edx
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shrl $2, %edx
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andl $(CHAR_PER_VEC - 1), %edx
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shrx %edx, %eax, %eax
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testl %eax, %eax
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# else
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leaq (VEC_SIZE * 3)(%rcx, %rax), %rax
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# endif
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# ifdef USE_AS_STRNLEN
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cmpq %rsi, %rax
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cmovnb %rsi, %rax
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shr %cl, %VRAX
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# endif
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jz L(cross_page_continue)
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bsf %VRAX, %VRAX
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ret
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L(ret_vec_x3):
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bsf %VRCX, %VRCX
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subq %rdi, %rax
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# ifdef USE_AS_WCSLEN
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subq $-(VEC_SIZE * 2), %rax
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shrq $2, %rax
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addq %rcx, %rax
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# else
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leaq (VEC_SIZE * 2)(%rcx, %rax), %rax
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# endif
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# ifdef USE_AS_STRNLEN
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cmpq %rsi, %rax
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cmovnb %rsi, %rax
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# endif
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ret
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L(ret_vec_x2):
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subq $-VEC_SIZE, %rax
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L(ret_vec_x1):
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bsf %VRCX, %VRCX
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subq %rdi, %rax
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# ifdef USE_AS_WCSLEN
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shrq $2, %rax
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# endif
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addq %rcx, %rax
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# ifdef USE_AS_STRNLEN
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cmpq %rsi, %rax
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cmovnb %rsi, %rax
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# endif
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ret
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L(page_cross):
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mov %rdi, %rax
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movl %edi, %ecx
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andl $(VEC_SIZE - 1), %ecx
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# ifdef USE_AS_WCSLEN
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sarl $2, %ecx
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# endif
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/* ecx contains number of w[char] to be skipped as a result
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of address alignment. */
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andq $-VEC_SIZE, %rax
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VPCMPEQ (%rax), %VMM(0), %k0
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KMOV %k0, %VRDX
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/* Ignore number of character for alignment adjustment. */
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shr %cl, %VRDX
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||||
# ifdef USE_AS_STRNLEN
|
||||
jnz L(page_cross_end)
|
||||
movl $CHAR_PER_VEC, %eax
|
||||
sub %ecx, %eax
|
||||
cmp %rax, %rsi
|
||||
ja L(align_more)
|
||||
# else
|
||||
jz L(align_more)
|
||||
# endif
|
||||
|
||||
L(page_cross_end):
|
||||
bsf %VRDX, %VRAX
|
||||
# ifdef USE_AS_STRNLEN
|
||||
cmpq %rsi, %rax
|
||||
cmovnb %esi, %eax
|
||||
# endif
|
||||
ret
|
||||
|
||||
END (STRLEN)
|
||||
END(STRLEN)
|
||||
#endif
|
||||
|
|
|
|||
|
|
@ -1,245 +1,7 @@
|
|||
/* strlen/strnlen/wcslen/wcsnlen optimized with 256-bit EVEX instructions.
|
||||
Copyright (C) 2021-2023 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
|
||||
<https://www.gnu.org/licenses/>. */
|
||||
|
||||
#include <isa-level.h>
|
||||
|
||||
#if ISA_SHOULD_BUILD (4)
|
||||
|
||||
# include <sysdep.h>
|
||||
|
||||
# ifndef STRLEN
|
||||
# define STRLEN __strlen_evex
|
||||
# endif
|
||||
|
||||
# ifndef VEC_SIZE
|
||||
# include "x86-evex256-vecs.h"
|
||||
# endif
|
||||
|
||||
# ifdef USE_AS_WCSLEN
|
||||
# define VPCMPEQ vpcmpeqd
|
||||
# define VPCMPNEQ vpcmpneqd
|
||||
# define VPTESTN vptestnmd
|
||||
# define VPTEST vptestmd
|
||||
# define VPMINU vpminud
|
||||
# define CHAR_SIZE 4
|
||||
# define CHAR_SIZE_SHIFT_REG(reg) sar $2, %reg
|
||||
# else
|
||||
# define VPCMPEQ vpcmpeqb
|
||||
# define VPCMPNEQ vpcmpneqb
|
||||
# define VPTESTN vptestnmb
|
||||
# define VPTEST vptestmb
|
||||
# define VPMINU vpminub
|
||||
# define CHAR_SIZE 1
|
||||
# define CHAR_SIZE_SHIFT_REG(reg)
|
||||
|
||||
# define REG_WIDTH VEC_SIZE
|
||||
# endif
|
||||
|
||||
# define CHAR_PER_VEC (VEC_SIZE / CHAR_SIZE)
|
||||
|
||||
# include "reg-macros.h"
|
||||
|
||||
# if CHAR_PER_VEC == 64
|
||||
|
||||
# define TAIL_RETURN_LBL first_vec_x2
|
||||
# define TAIL_RETURN_OFFSET (CHAR_PER_VEC * 2)
|
||||
|
||||
# define FALLTHROUGH_RETURN_LBL first_vec_x3
|
||||
# define FALLTHROUGH_RETURN_OFFSET (CHAR_PER_VEC * 3)
|
||||
|
||||
# else
|
||||
|
||||
# define TAIL_RETURN_LBL first_vec_x3
|
||||
# define TAIL_RETURN_OFFSET (CHAR_PER_VEC * 3)
|
||||
|
||||
# define FALLTHROUGH_RETURN_LBL first_vec_x2
|
||||
# define FALLTHROUGH_RETURN_OFFSET (CHAR_PER_VEC * 2)
|
||||
# endif
|
||||
|
||||
# define XZERO VMM_128(0)
|
||||
# define VZERO VMM(0)
|
||||
# define PAGE_SIZE 4096
|
||||
|
||||
.section SECTION(.text), "ax", @progbits
|
||||
ENTRY_P2ALIGN (STRLEN, 6)
|
||||
movl %edi, %eax
|
||||
vpxorq %XZERO, %XZERO, %XZERO
|
||||
andl $(PAGE_SIZE - 1), %eax
|
||||
cmpl $(PAGE_SIZE - VEC_SIZE), %eax
|
||||
ja L(cross_page_boundary)
|
||||
|
||||
/* Check the first VEC_SIZE bytes. Each bit in K0 represents a
|
||||
null byte. */
|
||||
VPCMPEQ (%rdi), %VZERO, %k0
|
||||
KMOV %k0, %VRAX
|
||||
test %VRAX, %VRAX
|
||||
jz L(aligned_more)
|
||||
bsf %VRAX, %VRAX
|
||||
ret
|
||||
|
||||
.p2align 4,, 8
|
||||
L(first_vec_x4):
|
||||
bsf %VRAX, %VRAX
|
||||
subl %ecx, %edi
|
||||
CHAR_SIZE_SHIFT_REG (edi)
|
||||
leal (CHAR_PER_VEC * 4)(%rdi, %rax), %eax
|
||||
ret
|
||||
|
||||
|
||||
|
||||
/* Aligned more for strnlen compares remaining length vs 2 *
|
||||
CHAR_PER_VEC, 4 * CHAR_PER_VEC, and 8 * CHAR_PER_VEC before
|
||||
going to the loop. */
|
||||
.p2align 4,, 10
|
||||
L(aligned_more):
|
||||
movq %rdi, %rcx
|
||||
andq $(VEC_SIZE * -1), %rdi
|
||||
L(cross_page_continue):
|
||||
/* Remaining length >= 2 * CHAR_PER_VEC so do VEC0/VEC1 without
|
||||
rechecking bounds. */
|
||||
VPCMPEQ (VEC_SIZE * 1)(%rdi), %VZERO, %k0
|
||||
KMOV %k0, %VRAX
|
||||
test %VRAX, %VRAX
|
||||
jnz L(first_vec_x1)
|
||||
|
||||
VPCMPEQ (VEC_SIZE * 2)(%rdi), %VZERO, %k0
|
||||
KMOV %k0, %VRAX
|
||||
test %VRAX, %VRAX
|
||||
jnz L(first_vec_x2)
|
||||
|
||||
VPCMPEQ (VEC_SIZE * 3)(%rdi), %VZERO, %k0
|
||||
KMOV %k0, %VRAX
|
||||
test %VRAX, %VRAX
|
||||
jnz L(first_vec_x3)
|
||||
|
||||
VPCMPEQ (VEC_SIZE * 4)(%rdi), %VZERO, %k0
|
||||
KMOV %k0, %VRAX
|
||||
test %VRAX, %VRAX
|
||||
jnz L(first_vec_x4)
|
||||
|
||||
subq $(VEC_SIZE * -1), %rdi
|
||||
|
||||
# if CHAR_PER_VEC == 64
|
||||
/* No partial register stalls on processors that we use evex512
|
||||
on and this saves code size. */
|
||||
xorb %dil, %dil
|
||||
# else
|
||||
andq $-(VEC_SIZE * 4), %rdi
|
||||
# endif
|
||||
|
||||
|
||||
|
||||
/* Compare 4 * VEC at a time forward. */
|
||||
.p2align 4
|
||||
L(loop_4x_vec):
|
||||
VMOVA (VEC_SIZE * 4)(%rdi), %VMM(1)
|
||||
VPMINU (VEC_SIZE * 5)(%rdi), %VMM(1), %VMM(2)
|
||||
VMOVA (VEC_SIZE * 6)(%rdi), %VMM(3)
|
||||
VPMINU (VEC_SIZE * 7)(%rdi), %VMM(3), %VMM(4)
|
||||
VPTESTN %VMM(2), %VMM(2), %k0
|
||||
VPTESTN %VMM(4), %VMM(4), %k2
|
||||
|
||||
subq $-(VEC_SIZE * 4), %rdi
|
||||
KORTEST %k0, %k2
|
||||
jz L(loop_4x_vec)
|
||||
|
||||
VPTESTN %VMM(1), %VMM(1), %k1
|
||||
KMOV %k1, %VRAX
|
||||
test %VRAX, %VRAX
|
||||
jnz L(first_vec_x0)
|
||||
|
||||
KMOV %k0, %VRAX
|
||||
test %VRAX, %VRAX
|
||||
jnz L(first_vec_x1)
|
||||
|
||||
VPTESTN %VMM(3), %VMM(3), %k0
|
||||
|
||||
# if CHAR_PER_VEC == 64
|
||||
KMOV %k0, %VRAX
|
||||
test %VRAX, %VRAX
|
||||
jnz L(first_vec_x2)
|
||||
KMOV %k2, %VRAX
|
||||
# else
|
||||
/* We can only combine last 2x VEC masks if CHAR_PER_VEC <= 32.
|
||||
*/
|
||||
kmovd %k2, %edx
|
||||
kmovd %k0, %eax
|
||||
salq $CHAR_PER_VEC, %rdx
|
||||
orq %rdx, %rax
|
||||
# endif
|
||||
|
||||
/* first_vec_x3 for strlen-ZMM and first_vec_x2 for strlen-YMM.
|
||||
*/
|
||||
.p2align 4,, 2
|
||||
L(FALLTHROUGH_RETURN_LBL):
|
||||
bsfq %rax, %rax
|
||||
subq %rcx, %rdi
|
||||
CHAR_SIZE_SHIFT_REG (rdi)
|
||||
leaq (FALLTHROUGH_RETURN_OFFSET)(%rdi, %rax), %rax
|
||||
ret
|
||||
|
||||
.p2align 4,, 8
|
||||
L(first_vec_x0):
|
||||
bsf %VRAX, %VRAX
|
||||
sub %rcx, %rdi
|
||||
CHAR_SIZE_SHIFT_REG (rdi)
|
||||
addq %rdi, %rax
|
||||
ret
|
||||
|
||||
.p2align 4,, 10
|
||||
L(first_vec_x1):
|
||||
bsf %VRAX, %VRAX
|
||||
sub %rcx, %rdi
|
||||
CHAR_SIZE_SHIFT_REG (rdi)
|
||||
leaq (CHAR_PER_VEC)(%rdi, %rax), %rax
|
||||
ret
|
||||
|
||||
.p2align 4,, 10
|
||||
/* first_vec_x2 for strlen-ZMM and first_vec_x3 for strlen-YMM.
|
||||
*/
|
||||
L(TAIL_RETURN_LBL):
|
||||
bsf %VRAX, %VRAX
|
||||
sub %VRCX, %VRDI
|
||||
CHAR_SIZE_SHIFT_REG (VRDI)
|
||||
lea (TAIL_RETURN_OFFSET)(%rdi, %rax), %VRAX
|
||||
ret
|
||||
|
||||
.p2align 4,, 8
|
||||
L(cross_page_boundary):
|
||||
movq %rdi, %rcx
|
||||
/* Align data to VEC_SIZE. */
|
||||
andq $-VEC_SIZE, %rdi
|
||||
|
||||
VPCMPEQ (%rdi), %VZERO, %k0
|
||||
|
||||
KMOV %k0, %VRAX
|
||||
# ifdef USE_AS_WCSLEN
|
||||
movl %ecx, %edx
|
||||
shrl $2, %edx
|
||||
andl $(CHAR_PER_VEC - 1), %edx
|
||||
shrx %edx, %eax, %eax
|
||||
testl %eax, %eax
|
||||
# else
|
||||
shr %cl, %VRAX
|
||||
# endif
|
||||
jz L(cross_page_continue)
|
||||
bsf %VRAX, %VRAX
|
||||
ret
|
||||
|
||||
END (STRLEN)
|
||||
#ifndef STRLEN
|
||||
# define STRLEN __strlen_evex
|
||||
#endif
|
||||
|
||||
#include "x86-evex256-vecs.h"
|
||||
#include "reg-macros.h"
|
||||
#include "strlen-evex-base.S"
|
||||
|
|
|
|||
|
|
@ -1,4 +1,264 @@
|
|||
#define STRLEN __strnlen_evex512
|
||||
#define USE_AS_STRNLEN 1
|
||||
/* Placeholder function, not used by any processor at the moment.
|
||||
Copyright (C) 2022-2023 Free Software Foundation, Inc.
|
||||
This file is part of the GNU C Library.
|
||||
|
||||
#include "strlen-evex512.S"
|
||||
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
|
||||
<https://www.gnu.org/licenses/>. */
|
||||
|
||||
#ifndef STRNLEN
|
||||
#define STRNLEN __strnlen_evex512
|
||||
#endif
|
||||
|
||||
#include "x86-evex512-vecs.h"
|
||||
#include "reg-macros.h"
|
||||
|
||||
#include <isa-level.h>
|
||||
|
||||
#if ISA_SHOULD_BUILD (4)
|
||||
|
||||
# include <sysdep.h>
|
||||
|
||||
# ifdef USE_AS_WCSLEN
|
||||
# define VPCMPEQ vpcmpeqd
|
||||
# define VPTESTN vptestnmd
|
||||
# define VPMINU vpminud
|
||||
# define CHAR_SIZE 4
|
||||
# else
|
||||
# define VPCMPEQ vpcmpeqb
|
||||
# define VPTESTN vptestnmb
|
||||
# define VPMINU vpminub
|
||||
# define CHAR_SIZE 1
|
||||
# endif
|
||||
|
||||
# define PAGE_SIZE 4096
|
||||
# define CHAR_PER_VEC (VEC_SIZE / CHAR_SIZE)
|
||||
|
||||
.section SECTION(.text),"ax",@progbits
|
||||
/* Aligning entry point to 64 byte, provides better performance for
|
||||
one vector length string. */
|
||||
ENTRY_P2ALIGN (STRNLEN, 6)
|
||||
/* Check zero length. */
|
||||
test %RSI_LP, %RSI_LP
|
||||
jz L(ret_max)
|
||||
# ifdef __ILP32__
|
||||
/* Clear the upper 32 bits. */
|
||||
movl %esi, %esi
|
||||
# endif
|
||||
|
||||
movl %edi, %eax
|
||||
vpxorq %VMM_128(0), %VMM_128(0), %VMM_128(0)
|
||||
sall $20, %eax
|
||||
cmpl $((PAGE_SIZE - VEC_SIZE) << 20), %eax
|
||||
ja L(page_cross)
|
||||
|
||||
/* Compare [w]char for null, mask bit will be set for match. */
|
||||
VPCMPEQ (%rdi), %VMM(0), %k0
|
||||
KMOV %k0, %VRCX
|
||||
/* Store max length in rax. */
|
||||
mov %rsi, %rax
|
||||
/* If rcx is 0, rax will have max length. We can not use VRCX
|
||||
and VRAX here for evex256 because, upper 32 bits may be
|
||||
undefined for ecx and eax. */
|
||||
bsfq %rcx, %rax
|
||||
cmp $CHAR_PER_VEC, %rax
|
||||
ja L(align_more)
|
||||
cmpq %rax, %rsi
|
||||
cmovb %esi, %eax
|
||||
ret
|
||||
|
||||
/* At this point vector max length reached. */
|
||||
.p2align 4,,3
|
||||
L(ret_max):
|
||||
movq %rsi, %rax
|
||||
ret
|
||||
|
||||
L(align_more):
|
||||
mov %rdi, %rax
|
||||
/* Align rax to VEC_SIZE. */
|
||||
andq $-VEC_SIZE, %rax
|
||||
movq %rdi, %rdx
|
||||
subq %rax, %rdx
|
||||
# ifdef USE_AS_WCSLEN
|
||||
shr $2, %VRDX
|
||||
# endif
|
||||
/* At this point rdx contains [w]chars already compared. */
|
||||
leaq -CHAR_PER_VEC(%rsi, %rdx), %rdx
|
||||
/* At this point rdx contains number of w[char] needs to go.
|
||||
Now onwards rdx will keep decrementing with each compare. */
|
||||
|
||||
/* Loop unroll 4 times for 4 vector loop. */
|
||||
VPCMPEQ VEC_SIZE(%rax), %VMM(0), %k0
|
||||
subq $-VEC_SIZE, %rax
|
||||
KMOV %k0, %VRCX
|
||||
test %VRCX, %VRCX
|
||||
jnz L(ret_vec_x1)
|
||||
|
||||
subq $CHAR_PER_VEC, %rdx
|
||||
jbe L(ret_max)
|
||||
|
||||
VPCMPEQ VEC_SIZE(%rax), %VMM(0), %k0
|
||||
KMOV %k0, %VRCX
|
||||
test %VRCX, %VRCX
|
||||
jnz L(ret_vec_x2)
|
||||
|
||||
subq $CHAR_PER_VEC, %rdx
|
||||
jbe L(ret_max)
|
||||
|
||||
VPCMPEQ (VEC_SIZE * 2)(%rax), %VMM(0), %k0
|
||||
KMOV %k0, %VRCX
|
||||
test %VRCX, %VRCX
|
||||
jnz L(ret_vec_x3)
|
||||
|
||||
subq $CHAR_PER_VEC, %rdx
|
||||
jbe L(ret_max)
|
||||
|
||||
VPCMPEQ (VEC_SIZE * 3)(%rax), %VMM(0), %k0
|
||||
KMOV %k0, %VRCX
|
||||
test %VRCX, %VRCX
|
||||
jnz L(ret_vec_x4)
|
||||
|
||||
subq $CHAR_PER_VEC, %rdx
|
||||
jbe L(ret_max)
|
||||
/* Save pointer before 4 x VEC_SIZE alignment. */
|
||||
movq %rax, %rcx
|
||||
|
||||
/* Align address to VEC_SIZE * 4 for loop. */
|
||||
andq $-(VEC_SIZE * 4), %rax
|
||||
|
||||
subq %rax, %rcx
|
||||
# ifdef USE_AS_WCSLEN
|
||||
shr $2, %VRCX
|
||||
# endif
|
||||
/* rcx contains number of [w]char will be recompared due to
|
||||
alignment fixes. rdx must be incremented by rcx to offset
|
||||
alignment adjustment. */
|
||||
addq %rcx, %rdx
|
||||
/* Need jump as we don't want to add/subtract rdx for first
|
||||
iteration of 4 x VEC_SIZE aligned loop. */
|
||||
|
||||
.p2align 4,,11
|
||||
L(loop):
|
||||
/* VPMINU and VPCMP combination provide better performance as
|
||||
compared to alternative combinations. */
|
||||
VMOVA (VEC_SIZE * 4)(%rax), %VMM(1)
|
||||
VPMINU (VEC_SIZE * 5)(%rax), %VMM(1), %VMM(2)
|
||||
VMOVA (VEC_SIZE * 6)(%rax), %VMM(3)
|
||||
VPMINU (VEC_SIZE * 7)(%rax), %VMM(3), %VMM(4)
|
||||
|
||||
VPTESTN %VMM(2), %VMM(2), %k0
|
||||
VPTESTN %VMM(4), %VMM(4), %k1
|
||||
|
||||
subq $-(VEC_SIZE * 4), %rax
|
||||
KORTEST %k0, %k1
|
||||
|
||||
jnz L(loopend)
|
||||
subq $(CHAR_PER_VEC * 4), %rdx
|
||||
ja L(loop)
|
||||
mov %rsi, %rax
|
||||
ret
|
||||
|
||||
L(loopend):
|
||||
|
||||
VPTESTN %VMM(1), %VMM(1), %k2
|
||||
KMOV %k2, %VRCX
|
||||
test %VRCX, %VRCX
|
||||
jnz L(ret_vec_x1)
|
||||
|
||||
KMOV %k0, %VRCX
|
||||
/* At this point, if k0 is non zero, null char must be in the
|
||||
second vector. */
|
||||
test %VRCX, %VRCX
|
||||
jnz L(ret_vec_x2)
|
||||
|
||||
VPTESTN %VMM(3), %VMM(3), %k3
|
||||
KMOV %k3, %VRCX
|
||||
test %VRCX, %VRCX
|
||||
jnz L(ret_vec_x3)
|
||||
/* At this point null [w]char must be in the fourth vector so no
|
||||
need to check. */
|
||||
KMOV %k1, %VRCX
|
||||
|
||||
/* Fourth, third, second vector terminating are pretty much
|
||||
same, implemented this way to avoid branching and reuse code
|
||||
from pre loop exit condition. */
|
||||
L(ret_vec_x4):
|
||||
bsf %VRCX, %VRCX
|
||||
subq %rdi, %rax
|
||||
# ifdef USE_AS_WCSLEN
|
||||
subq $-(VEC_SIZE * 3), %rax
|
||||
shrq $2, %rax
|
||||
addq %rcx, %rax
|
||||
# else
|
||||
leaq (VEC_SIZE * 3)(%rcx, %rax), %rax
|
||||
# endif
|
||||
|
||||
cmpq %rsi, %rax
|
||||
cmovnb %rsi, %rax
|
||||
ret
|
||||
|
||||
L(ret_vec_x3):
|
||||
bsf %VRCX, %VRCX
|
||||
subq %rdi, %rax
|
||||
# ifdef USE_AS_WCSLEN
|
||||
subq $-(VEC_SIZE * 2), %rax
|
||||
shrq $2, %rax
|
||||
addq %rcx, %rax
|
||||
# else
|
||||
leaq (VEC_SIZE * 2)(%rcx, %rax), %rax
|
||||
# endif
|
||||
cmpq %rsi, %rax
|
||||
cmovnb %rsi, %rax
|
||||
ret
|
||||
|
||||
L(ret_vec_x2):
|
||||
subq $-VEC_SIZE, %rax
|
||||
L(ret_vec_x1):
|
||||
bsf %VRCX, %VRCX
|
||||
subq %rdi, %rax
|
||||
# ifdef USE_AS_WCSLEN
|
||||
shrq $2, %rax
|
||||
# endif
|
||||
addq %rcx, %rax
|
||||
cmpq %rsi, %rax
|
||||
cmovnb %rsi, %rax
|
||||
ret
|
||||
|
||||
L(page_cross):
|
||||
mov %rdi, %rax
|
||||
movl %edi, %ecx
|
||||
andl $(VEC_SIZE - 1), %ecx
|
||||
# ifdef USE_AS_WCSLEN
|
||||
sarl $2, %ecx
|
||||
# endif
|
||||
/* ecx contains number of w[char] to be skipped as a result
|
||||
of address alignment. */
|
||||
andq $-VEC_SIZE, %rax
|
||||
VPCMPEQ (%rax), %VMM(0), %k0
|
||||
KMOV %k0, %VRDX
|
||||
/* Ignore number of character for alignment adjustment. */
|
||||
shr %cl, %VRDX
|
||||
jnz L(page_cross_end)
|
||||
movl $CHAR_PER_VEC, %eax
|
||||
sub %ecx, %eax
|
||||
cmp %rax, %rsi
|
||||
ja L(align_more)
|
||||
|
||||
L(page_cross_end):
|
||||
bsf %VRDX, %VRAX
|
||||
cmpq %rsi, %rax
|
||||
cmovnb %esi, %eax
|
||||
ret
|
||||
|
||||
END (STRNLEN)
|
||||
#endif
|
||||
|
|
|
|||
|
|
@ -1,4 +1,8 @@
|
|||
#define STRLEN __wcslen_evex512
|
||||
#ifndef WCSLEN
|
||||
# define WCSLEN __wcslen_evex512
|
||||
#endif
|
||||
|
||||
#define STRLEN WCSLEN
|
||||
#define USE_AS_WCSLEN 1
|
||||
|
||||
#include "strlen-evex512.S"
|
||||
|
|
|
|||
|
|
@ -1,5 +1,8 @@
|
|||
#define STRLEN __wcsnlen_evex512
|
||||
#define USE_AS_WCSLEN 1
|
||||
#define USE_AS_STRNLEN 1
|
||||
#ifndef WCSNLEN
|
||||
# define WCSNLEN __wcsnlen_evex512
|
||||
#endif
|
||||
|
||||
#include "strlen-evex512.S"
|
||||
#define STRNLEN WCSNLEN
|
||||
#define USE_AS_WCSLEN 1
|
||||
|
||||
#include "strnlen-evex512.S"
|
||||
|
|
|
|||
Loading…
Add table
Reference in a new issue