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-rw-r--r--REORG.TODO/sysdeps/x86_64/memchr.S315
1 files changed, 315 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/x86_64/memchr.S b/REORG.TODO/sysdeps/x86_64/memchr.S
new file mode 100644
index 0000000000..d3be012424
--- /dev/null
+++ b/REORG.TODO/sysdeps/x86_64/memchr.S
@@ -0,0 +1,315 @@
+/* Copyright (C) 2011-2017 Free Software Foundation, Inc.
+ Contributed by Intel Corporation.
+ 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
+ <http://www.gnu.org/licenses/>. */
+
+#include <sysdep.h>
+
+/* fast SSE2 version with using pmaxub and 64 byte loop */
+
+ .text
+ENTRY(memchr)
+ movd %esi, %xmm1
+ mov %edi, %ecx
+
+ punpcklbw %xmm1, %xmm1
+ test %rdx, %rdx
+ jz L(return_null)
+ punpcklbw %xmm1, %xmm1
+
+ and $63, %ecx
+ pshufd $0, %xmm1, %xmm1
+
+ cmp $48, %ecx
+ ja L(crosscache)
+
+ movdqu (%rdi), %xmm0
+ pcmpeqb %xmm1, %xmm0
+ pmovmskb %xmm0, %eax
+ test %eax, %eax
+
+ jnz L(matches_1)
+ sub $16, %rdx
+ jbe L(return_null)
+ add $16, %rdi
+ and $15, %ecx
+ and $-16, %rdi
+ add %rcx, %rdx
+ sub $64, %rdx
+ jbe L(exit_loop)
+ jmp L(loop_prolog)
+
+ .p2align 4
+L(crosscache):
+ and $15, %ecx
+ and $-16, %rdi
+ movdqa (%rdi), %xmm0
+
+ pcmpeqb %xmm1, %xmm0
+/* Check if there is a match. */
+ pmovmskb %xmm0, %eax
+/* Remove the leading bytes. */
+ sar %cl, %eax
+ test %eax, %eax
+ je L(unaligned_no_match)
+/* Check which byte is a match. */
+ bsf %eax, %eax
+
+ sub %rax, %rdx
+ jbe L(return_null)
+ add %rdi, %rax
+ add %rcx, %rax
+ ret
+
+ .p2align 4
+L(unaligned_no_match):
+ /* "rcx" is less than 16. Calculate "rdx + rcx - 16" by using
+ "rdx - (16 - rcx)" instead of "(rdx + rcx) - 16" to void
+ possible addition overflow. */
+ neg %rcx
+ add $16, %rcx
+ sub %rcx, %rdx
+ jbe L(return_null)
+ add $16, %rdi
+ sub $64, %rdx
+ jbe L(exit_loop)
+
+ .p2align 4
+L(loop_prolog):
+ movdqa (%rdi), %xmm0
+ pcmpeqb %xmm1, %xmm0
+ pmovmskb %xmm0, %eax
+ test %eax, %eax
+ jnz L(matches)
+
+ movdqa 16(%rdi), %xmm2
+ pcmpeqb %xmm1, %xmm2
+ pmovmskb %xmm2, %eax
+ test %eax, %eax
+ jnz L(matches16)
+
+ movdqa 32(%rdi), %xmm3
+ pcmpeqb %xmm1, %xmm3
+ pmovmskb %xmm3, %eax
+ test %eax, %eax
+ jnz L(matches32)
+
+ movdqa 48(%rdi), %xmm4
+ pcmpeqb %xmm1, %xmm4
+ add $64, %rdi
+ pmovmskb %xmm4, %eax
+ test %eax, %eax
+ jnz L(matches0)
+
+ test $0x3f, %rdi
+ jz L(align64_loop)
+
+ sub $64, %rdx
+ jbe L(exit_loop)
+
+ movdqa (%rdi), %xmm0
+ pcmpeqb %xmm1, %xmm0
+ pmovmskb %xmm0, %eax
+ test %eax, %eax
+ jnz L(matches)
+
+ movdqa 16(%rdi), %xmm2
+ pcmpeqb %xmm1, %xmm2
+ pmovmskb %xmm2, %eax
+ test %eax, %eax
+ jnz L(matches16)
+
+ movdqa 32(%rdi), %xmm3
+ pcmpeqb %xmm1, %xmm3
+ pmovmskb %xmm3, %eax
+ test %eax, %eax
+ jnz L(matches32)
+
+ movdqa 48(%rdi), %xmm3
+ pcmpeqb %xmm1, %xmm3
+ pmovmskb %xmm3, %eax
+
+ add $64, %rdi
+ test %eax, %eax
+ jnz L(matches0)
+
+ mov %rdi, %rcx
+ and $-64, %rdi
+ and $63, %ecx
+ add %rcx, %rdx
+
+ .p2align 4
+L(align64_loop):
+ sub $64, %rdx
+ jbe L(exit_loop)
+ movdqa (%rdi), %xmm0
+ movdqa 16(%rdi), %xmm2
+ movdqa 32(%rdi), %xmm3
+ movdqa 48(%rdi), %xmm4
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm1, %xmm2
+ pcmpeqb %xmm1, %xmm3
+ pcmpeqb %xmm1, %xmm4
+
+ pmaxub %xmm0, %xmm3
+ pmaxub %xmm2, %xmm4
+ pmaxub %xmm3, %xmm4
+ pmovmskb %xmm4, %eax
+
+ add $64, %rdi
+
+ test %eax, %eax
+ jz L(align64_loop)
+
+ sub $64, %rdi
+
+ pmovmskb %xmm0, %eax
+ test %eax, %eax
+ jnz L(matches)
+
+ pmovmskb %xmm2, %eax
+ test %eax, %eax
+ jnz L(matches16)
+
+ movdqa 32(%rdi), %xmm3
+ pcmpeqb %xmm1, %xmm3
+
+ pcmpeqb 48(%rdi), %xmm1
+ pmovmskb %xmm3, %eax
+ test %eax, %eax
+ jnz L(matches32)
+
+ pmovmskb %xmm1, %eax
+ bsf %eax, %eax
+ lea 48(%rdi, %rax), %rax
+ ret
+
+ .p2align 4
+L(exit_loop):
+ add $32, %edx
+ jle L(exit_loop_32)
+
+ movdqa (%rdi), %xmm0
+ pcmpeqb %xmm1, %xmm0
+ pmovmskb %xmm0, %eax
+ test %eax, %eax
+ jnz L(matches)
+
+ movdqa 16(%rdi), %xmm2
+ pcmpeqb %xmm1, %xmm2
+ pmovmskb %xmm2, %eax
+ test %eax, %eax
+ jnz L(matches16)
+
+ movdqa 32(%rdi), %xmm3
+ pcmpeqb %xmm1, %xmm3
+ pmovmskb %xmm3, %eax
+ test %eax, %eax
+ jnz L(matches32_1)
+ sub $16, %edx
+ jle L(return_null)
+
+ pcmpeqb 48(%rdi), %xmm1
+ pmovmskb %xmm1, %eax
+ test %eax, %eax
+ jnz L(matches48_1)
+ xor %eax, %eax
+ ret
+
+ .p2align 4
+L(exit_loop_32):
+ add $32, %edx
+ movdqa (%rdi), %xmm0
+ pcmpeqb %xmm1, %xmm0
+ pmovmskb %xmm0, %eax
+ test %eax, %eax
+ jnz L(matches_1)
+ sub $16, %edx
+ jbe L(return_null)
+
+ pcmpeqb 16(%rdi), %xmm1
+ pmovmskb %xmm1, %eax
+ test %eax, %eax
+ jnz L(matches16_1)
+ xor %eax, %eax
+ ret
+
+ .p2align 4
+L(matches0):
+ bsf %eax, %eax
+ lea -16(%rax, %rdi), %rax
+ ret
+
+ .p2align 4
+L(matches):
+ bsf %eax, %eax
+ add %rdi, %rax
+ ret
+
+ .p2align 4
+L(matches16):
+ bsf %eax, %eax
+ lea 16(%rax, %rdi), %rax
+ ret
+
+ .p2align 4
+L(matches32):
+ bsf %eax, %eax
+ lea 32(%rax, %rdi), %rax
+ ret
+
+ .p2align 4
+L(matches_1):
+ bsf %eax, %eax
+ sub %rax, %rdx
+ jbe L(return_null)
+ add %rdi, %rax
+ ret
+
+ .p2align 4
+L(matches16_1):
+ bsf %eax, %eax
+ sub %rax, %rdx
+ jbe L(return_null)
+ lea 16(%rdi, %rax), %rax
+ ret
+
+ .p2align 4
+L(matches32_1):
+ bsf %eax, %eax
+ sub %rax, %rdx
+ jbe L(return_null)
+ lea 32(%rdi, %rax), %rax
+ ret
+
+ .p2align 4
+L(matches48_1):
+ bsf %eax, %eax
+ sub %rax, %rdx
+ jbe L(return_null)
+ lea 48(%rdi, %rax), %rax
+ ret
+
+ .p2align 4
+L(return_null):
+ xor %eax, %eax
+ ret
+END(memchr)
+
+strong_alias (memchr, __memchr)
+
+libc_hidden_builtin_def(memchr)