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authorThe Android Open Source Project <initial-contribution@android.com>2008-10-21 07:00:00 -0700
committerThe Android Open Source Project <initial-contribution@android.com>2008-10-21 07:00:00 -0700
commita27d2baa0c1a2ec70f47ea9199b1dd6762c8a349 (patch)
treedefd1cc07d16ad2f3b21154114e092d11c94c5bb /libc/arch-x86/string/strcmp.S
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Initial Contributionandroid-1.0
Diffstat (limited to 'libc/arch-x86/string/strcmp.S')
-rw-r--r--libc/arch-x86/string/strcmp.S81
1 files changed, 81 insertions, 0 deletions
diff --git a/libc/arch-x86/string/strcmp.S b/libc/arch-x86/string/strcmp.S
new file mode 100644
index 0000000..22ba546
--- /dev/null
+++ b/libc/arch-x86/string/strcmp.S
@@ -0,0 +1,81 @@
+/* $OpenBSD: strcmp.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(strcmp)
+ movl 0x04(%esp),%eax
+ movl 0x08(%esp),%edx
+ jmp L2 /* Jump into the loop! */
+
+ .align 2,0x90
+L1: incl %eax
+ incl %edx
+L2: movb (%eax),%cl
+ testb %cl,%cl /* null terminator??? */
+ jz L3
+ cmpb %cl,(%edx) /* chars match??? */
+ jne L3
+ incl %eax
+ incl %edx
+ movb (%eax),%cl
+ testb %cl,%cl
+ jz L3
+ cmpb %cl,(%edx)
+ jne L3
+ incl %eax
+ incl %edx
+ movb (%eax),%cl
+ testb %cl,%cl
+ jz L3
+ cmpb %cl,(%edx)
+ jne L3
+ incl %eax
+ incl %edx
+ movb (%eax),%cl
+ testb %cl,%cl
+ jz L3
+ cmpb %cl,(%edx)
+ jne L3
+ incl %eax
+ incl %edx
+ movb (%eax),%cl
+ testb %cl,%cl
+ jz L3
+ cmpb %cl,(%edx)
+ jne L3
+ incl %eax
+ incl %edx
+ movb (%eax),%cl
+ testb %cl,%cl
+ jz L3
+ cmpb %cl,(%edx)
+ jne L3
+ incl %eax
+ incl %edx
+ movb (%eax),%cl
+ testb %cl,%cl
+ jz L3
+ cmpb %cl,(%edx)
+ jne L3
+ incl %eax
+ incl %edx
+ movb (%eax),%cl
+ testb %cl,%cl
+ jz L3
+ cmpb %cl,(%edx)
+ je L1
+ .align 2, 0x90
+L3: movzbl (%eax),%eax /* unsigned comparison */
+ movzbl (%edx),%edx
+ subl %edx,%eax
+ ret