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author | The Android Open Source Project <initial-contribution@android.com> | 2008-10-21 07:00:00 -0700 |
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committer | The Android Open Source Project <initial-contribution@android.com> | 2008-10-21 07:00:00 -0700 |
commit | a27d2baa0c1a2ec70f47ea9199b1dd6762c8a349 (patch) | |
tree | defd1cc07d16ad2f3b21154114e092d11c94c5bb /libc/arch-x86/string/strncmp.S | |
download | bionic-a27d2baa0c1a2ec70f47ea9199b1dd6762c8a349.zip bionic-a27d2baa0c1a2ec70f47ea9199b1dd6762c8a349.tar.gz bionic-a27d2baa0c1a2ec70f47ea9199b1dd6762c8a349.tar.bz2 |
Initial Contributionandroid-1.0
Diffstat (limited to 'libc/arch-x86/string/strncmp.S')
-rw-r--r-- | libc/arch-x86/string/strncmp.S | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/libc/arch-x86/string/strncmp.S b/libc/arch-x86/string/strncmp.S new file mode 100644 index 0000000..5aa88d7 --- /dev/null +++ b/libc/arch-x86/string/strncmp.S @@ -0,0 +1,113 @@ +/* $OpenBSD: strncmp.S,v 1.3 2005/08/07 11:30:38 espie Exp $ */ +/* + * Written by J.T. Conklin <jtc@netbsd.org>. + * Public domain. + */ + +#include <machine/asm.h> + +/* + * NOTE: I've unrolled the loop eight times: large enough to make a + * significant difference, and small enough not to totally trash the + * cache. + */ + +ENTRY(strncmp) + pushl %ebx + movl 8(%esp),%eax + movl 12(%esp),%ecx + movl 16(%esp),%edx + testl %edx,%edx + jmp L2 /* Jump into the loop! */ + + .align 2,0x90 +L1: incl %eax + incl %ecx + decl %edx +L2: jz L4 /* strings are equal */ + movb (%eax),%bl + testb %bl,%bl + jz L3 + cmpb %bl,(%ecx) + jne L3 + + incl %eax + incl %ecx + decl %edx + jz L4 + movb (%eax),%bl + testb %bl,%bl + jz L3 + cmpb %bl,(%ecx) + jne L3 + + incl %eax + incl %ecx + decl %edx + jz L4 + movb (%eax),%bl + testb %bl,%bl + jz L3 + cmpb %bl,(%ecx) + jne L3 + + incl %eax + incl %ecx + decl %edx + jz L4 + movb (%eax),%bl + testb %bl,%bl + jz L3 + cmpb %bl,(%ecx) + jne L3 + + incl %eax + incl %ecx + decl %edx + jz L4 + movb (%eax),%bl + testb %bl,%bl + jz L3 + cmpb %bl,(%ecx) + jne L3 + + incl %eax + incl %ecx + decl %edx + jz L4 + movb (%eax),%bl + testb %bl,%bl + jz L3 + cmpb %bl,(%ecx) + jne L3 + + incl %eax + incl %ecx + decl %edx + jz L4 + movb (%eax),%bl + testb %bl,%bl + jz L3 + cmpb %bl,(%ecx) + jne L3 + + incl %eax + incl %ecx + decl %edx + jz L4 + movb (%eax),%bl + testb %bl,%bl + jz L3 + cmpb %bl,(%ecx) + je L1 + + .align 2,0x90 +L3: movzbl (%eax),%eax /* unsigned comparision */ + movzbl (%ecx),%ecx + subl %ecx,%eax + popl %ebx + ret + .align 2,0x90 +L4: xorl %eax,%eax + popl %ebx + ret |