From 30cb625a21bc7ad450fdc45d1f682e2b27c353de Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Mon, 5 Jun 2017 07:58:11 -0700 Subject: x86-64: Update strlen.S to support wcslen/wcsnlen The difference between strlen and wcslen is byte vs int. We can replace pminub and pcmpeqb with pminud and pcmpeqd to turn strlen into wcslen. * sysdeps/x86_64/strlen.S (PMINU): New. (PCMPEQ): Likewise. (SHIFT_RETURN): Likewise. (FIND_ZERO): Replace pcmpeqb with PCMPEQ. (strlen): Add SHIFT_RETURN before ret. Replace pcmpeqb and pminub with PCMPEQ and PMINU. * sysdeps/x86_64/wcsnlen.S: New file. --- sysdeps/x86_64/strlen.S | 61 +++++++++++++++++++++++++++++++----------------- sysdeps/x86_64/wcsnlen.S | 7 ++++++ 2 files changed, 47 insertions(+), 21 deletions(-) create mode 100644 sysdeps/x86_64/wcsnlen.S (limited to 'sysdeps/x86_64') diff --git a/sysdeps/x86_64/strlen.S b/sysdeps/x86_64/strlen.S index 5896e6b9ee..b5ab117c79 100644 --- a/sysdeps/x86_64/strlen.S +++ b/sysdeps/x86_64/strlen.S @@ -1,4 +1,4 @@ -/* SSE2 version of strlen. +/* SSE2 version of strlen/wcslen. Copyright (C) 2012-2017 Free Software Foundation, Inc. This file is part of the GNU C Library. @@ -18,6 +18,16 @@ #include +#ifdef AS_WCSLEN +# define PMINU pminud +# define PCMPEQ pcmpeqd +# define SHIFT_RETURN shrq $2, %rax +#else +# define PMINU pminub +# define PCMPEQ pcmpeqb +# define SHIFT_RETURN +#endif + /* Long lived register in strlen(s), strnlen(s, n) are: %xmm3 - zero @@ -32,10 +42,10 @@ ENTRY(strlen) /* Test 64 bytes from %rax for zero. Save result as bitmask in %rdx. */ #define FIND_ZERO \ - pcmpeqb (%rax), %xmm0; \ - pcmpeqb 16(%rax), %xmm1; \ - pcmpeqb 32(%rax), %xmm2; \ - pcmpeqb 48(%rax), %xmm3; \ + PCMPEQ (%rax), %xmm0; \ + PCMPEQ 16(%rax), %xmm1; \ + PCMPEQ 32(%rax), %xmm2; \ + PCMPEQ 48(%rax), %xmm3; \ pmovmskb %xmm0, %esi; \ pmovmskb %xmm1, %edx; \ pmovmskb %xmm2, %r8d; \ @@ -54,6 +64,9 @@ ENTRY(strlen) xor %rax, %rax ret L(n_nonzero): +# ifdef AS_WCSLEN + shlq $2, %rsi +# endif /* Initialize long lived registers. */ @@ -96,6 +109,7 @@ L(n_nonzero): test %rdx, %rdx; \ je L(lab); \ bsfq %rdx, %rax; \ + SHIFT_RETURN; \ ret #ifdef AS_STRNLEN @@ -104,19 +118,20 @@ L(n_nonzero): #else /* Test first 16 bytes unaligned. */ movdqu (%rax), %xmm4 - pcmpeqb %xmm0, %xmm4 + PCMPEQ %xmm0, %xmm4 pmovmskb %xmm4, %edx test %edx, %edx je L(next48_bytes) bsf %edx, %eax /* If eax is zeroed 16bit bsf can be used. */ + SHIFT_RETURN ret L(next48_bytes): /* Same as FIND_ZERO except we do not check first 16 bytes. */ andq $-16, %rax - pcmpeqb 16(%rax), %xmm1 - pcmpeqb 32(%rax), %xmm2 - pcmpeqb 48(%rax), %xmm3 + PCMPEQ 16(%rax), %xmm1 + PCMPEQ 32(%rax), %xmm2 + PCMPEQ 48(%rax), %xmm3 pmovmskb %xmm1, %edx pmovmskb %xmm2, %r8d pmovmskb %xmm3, %ecx @@ -145,6 +160,7 @@ L(strnlen_ret): test %rdx, %rdx je L(loop_init) bsfq %rdx, %rax + SHIFT_RETURN ret #endif .p2align 4 @@ -161,10 +177,10 @@ L(loop): je L(exit_end) movdqa (%rax), %xmm0 - pminub 16(%rax), %xmm0 - pminub 32(%rax), %xmm0 - pminub 48(%rax), %xmm0 - pcmpeqb %xmm3, %xmm0 + PMINU 16(%rax), %xmm0 + PMINU 32(%rax), %xmm0 + PMINU 48(%rax), %xmm0 + PCMPEQ %xmm3, %xmm0 pmovmskb %xmm0, %edx testl %edx, %edx jne L(exit) @@ -182,6 +198,7 @@ L(first): bsfq %rdx, %rdx addq %rdx, %rax subq %rdi, %rax + SHIFT_RETURN ret .p2align 4 @@ -192,6 +209,7 @@ L(exit): bsfq %rdx, %rdx addq %rdx, %rax subq %rdi, %rax + SHIFT_RETURN ret #else @@ -201,10 +219,10 @@ L(exit): L(loop): movdqa 64(%rax), %xmm0 - pminub 80(%rax), %xmm0 - pminub 96(%rax), %xmm0 - pminub 112(%rax), %xmm0 - pcmpeqb %xmm3, %xmm0 + PMINU 80(%rax), %xmm0 + PMINU 96(%rax), %xmm0 + PMINU 112(%rax), %xmm0 + PCMPEQ %xmm3, %xmm0 pmovmskb %xmm0, %edx testl %edx, %edx jne L(exit64) @@ -212,10 +230,10 @@ L(loop): subq $-128, %rax movdqa (%rax), %xmm0 - pminub 16(%rax), %xmm0 - pminub 32(%rax), %xmm0 - pminub 48(%rax), %xmm0 - pcmpeqb %xmm3, %xmm0 + PMINU 16(%rax), %xmm0 + PMINU 32(%rax), %xmm0 + PMINU 48(%rax), %xmm0 + PCMPEQ %xmm3, %xmm0 pmovmskb %xmm0, %edx testl %edx, %edx jne L(exit0) @@ -231,6 +249,7 @@ L(exit0): bsfq %rdx, %rdx addq %rdx, %rax subq %rdi, %rax + SHIFT_RETURN ret #endif diff --git a/sysdeps/x86_64/wcsnlen.S b/sysdeps/x86_64/wcsnlen.S new file mode 100644 index 0000000000..968bb693b4 --- /dev/null +++ b/sysdeps/x86_64/wcsnlen.S @@ -0,0 +1,7 @@ +#define AS_WCSLEN +#define AS_STRNLEN +#define strlen __wcsnlen + +#include "strlen.S" + +weak_alias(__wcsnlen, wcsnlen) -- cgit 1.4.1