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-rw-r--r--arch/sparc/lib/strlen.S81
1 files changed, 81 insertions, 0 deletions
diff --git a/arch/sparc/lib/strlen.S b/arch/sparc/lib/strlen.S
new file mode 100644
index 000000000000..ed9a763368cd
--- /dev/null
+++ b/arch/sparc/lib/strlen.S
@@ -0,0 +1,81 @@
+/* strlen.S: Sparc optimized strlen code
+ * Hand optimized from GNU libc's strlen
+ * Copyright (C) 1991,1996 Free Software Foundation
+ * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
+ * Copyright (C) 1996 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
+ */
+
+#define LO_MAGIC 0x01010101
+#define HI_MAGIC 0x80808080
+
+0:
+ ldub [%o0], %o5
+ cmp %o5, 0
+ be 1f
+ add %o0, 1, %o0
+ andcc %o0, 3, %g0
+ be 4f
+ or %o4, %lo(HI_MAGIC), %o3
+ ldub [%o0], %o5
+ cmp %o5, 0
+ be 2f
+ add %o0, 1, %o0
+ andcc %o0, 3, %g0
+ be 5f
+ sethi %hi(LO_MAGIC), %o4
+ ldub [%o0], %o5
+ cmp %o5, 0
+ be 3f
+ add %o0, 1, %o0
+ b 8f
+ or %o4, %lo(LO_MAGIC), %o2
+1:
+ retl
+ mov 0, %o0
+2:
+ retl
+ mov 1, %o0
+3:
+ retl
+ mov 2, %o0
+
+ .align 4
+ .global strlen
+strlen:
+ mov %o0, %o1
+ andcc %o0, 3, %g0
+ bne 0b
+ sethi %hi(HI_MAGIC), %o4
+ or %o4, %lo(HI_MAGIC), %o3
+4:
+ sethi %hi(LO_MAGIC), %o4
+5:
+ or %o4, %lo(LO_MAGIC), %o2
+8:
+ ld [%o0], %o5
+2:
+ sub %o5, %o2, %o4
+ andcc %o4, %o3, %g0
+ be 8b
+ add %o0, 4, %o0
+
+ /* Check every byte. */
+ srl %o5, 24, %g5
+ andcc %g5, 0xff, %g0
+ be 1f
+ add %o0, -4, %o4
+ srl %o5, 16, %g5
+ andcc %g5, 0xff, %g0
+ be 1f
+ add %o4, 1, %o4
+ srl %o5, 8, %g5
+ andcc %g5, 0xff, %g0
+ be 1f
+ add %o4, 1, %o4
+ andcc %o5, 0xff, %g0
+ bne,a 2b
+ ld [%o0], %o5
+ add %o4, 1, %o4
+1:
+ retl
+ sub %o4, %o1, %o0