patch-2.1.30 linux/arch/sparc64/lib/strlen_user.S

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diff -u --recursive --new-file v2.1.29/linux/arch/sparc64/lib/strlen_user.S linux/arch/sparc64/lib/strlen_user.S
@@ -0,0 +1,99 @@
+/* strlen_user.S: Sparc64 optimized strlen_user code
+ *
+ * Return length of string in userspace including terminating 0
+ * or 0 for error
+ *
+ * Copyright (C) 1991,1996 Free Software Foundation
+ * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
+ * Copyright (C) 1996,1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
+ */
+
+#define LO_MAGIC 0x01010101
+#define HI_MAGIC 0x80808080
+
+	.align 4
+	.global __strlen_user
+__strlen_user:
+	mov	%o0, %o1
+	andcc	%o0, 3, %g0
+	be,pt	%icc, 9f
+	 sethi	%hi(HI_MAGIC), %o4
+10:
+	ldub	[%o0], %o5
+	brz,pn	%o5, 21f
+	 add	%o0, 1, %o0
+	andcc	%o0, 3, %g0
+	be,pn	%icc, 4f
+	 or	%o4, %lo(HI_MAGIC), %o3
+11:
+	ldub	[%o0], %o5
+	brz,pn	%o5, 22f
+	 add	%o0, 1, %o0
+	andcc	%o0, 3, %g0
+	be,pt	%icc, 5f
+	 sethi	%hi(LO_MAGIC), %o4
+12:
+	ldub	[%o0], %o5
+	brz,pn	%o5, 23f
+	 add	%o0, 1, %o0
+	ba,pt	%icc, 13f
+	 or	%o4, %lo(LO_MAGIC), %o2
+9:
+	or	%o4, %lo(HI_MAGIC), %o3
+4:
+	sethi	%hi(LO_MAGIC), %o4
+5:
+	or	%o4, %lo(LO_MAGIC), %o2
+13:
+	ld	[%o0], %o5
+2:
+	sub	%o5, %o2, %o4
+	andcc	%o4, %o3, %g0
+	be,pt	%icc, 13b
+	 add	%o0, 4, %o0
+
+	/* Check every byte. */
+	srl	%o5, 24, %g5
+	andcc	%g5, 0xff, %g0
+	be,pn	%icc, 1f
+	 add	%o0, -3, %o4
+	srl	%o5, 16, %g5
+	andcc	%g5, 0xff, %g0
+	be,pn	%icc, 1f
+	 add	%o4, 1, %o4
+	srl	%o5, 8, %g5
+	andcc	%g5, 0xff, %g0
+	be,pn	%icc, 1f
+	 add	%o4, 1, %o4
+	andcc	%o5, 0xff, %g0
+	bne,a,pt %icc, 2b
+14:
+	 ld	[%o0], %o5
+	add	%o4, 1, %o4
+1:
+	retl
+	 sub	%o4, %o1, %o0
+21:
+	retl
+	 mov	1, %o0
+22:
+	retl
+	 mov	2, %o0
+23:
+	retl
+	 mov	3, %o0
+
+        .section .fixup,#alloc,#execinstr
+        .align  4
+30:
+        retl
+         clr    %o0
+
+	.section __ex_table,#alloc
+	.align	4
+
+	.word	10b, 30b
+	.word	11b, 30b
+	.word	12b, 30b
+	.word	13b, 30b
+	.word	14b, 30b

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