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-rw-r--r--sysdeps/i386/i586/strchr.S16
-rw-r--r--sysdeps/i386/i586/strlen.S26
2 files changed, 19 insertions, 23 deletions
diff --git a/sysdeps/i386/i586/strchr.S b/sysdeps/i386/i586/strchr.S
index 30de6b069d..100cbbc706 100644
--- a/sysdeps/i386/i586/strchr.S
+++ b/sysdeps/i386/i586/strchr.S
@@ -1,6 +1,6 @@
/* strchr -- find character CH in a NUL terminated string.
Highly optimized version for ix85, x>=5.
-Copyright (C) 1995 Free Software Foundation, Inc.
+Copyright (C) 1995, 1996 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper, <drepper@gnu.ai.mit.edu>.
@@ -68,9 +68,10 @@ ENTRY (strchr)
andl $3, %edi /* mask alignment bits */
jz L11 /* alignment is 0 => start loop */
+ jp L0 /* exactly two bits set */
movb (%eax), %cl /* load single byte */
- cmpb %cl, %dl /* is byte == C? */
+ cmpb (%eax), %dl /* is byte == C? */
je L2 /* aligned => return pointer */
@@ -78,26 +79,21 @@ ENTRY (strchr)
je L3 /* yes => return NULL */
incl %eax /* increment pointer */
- cmp $3, %edi /* was alignment == 3? */
+ xorl $3, %edi /* was alignment == 3? */
+L0: movb (%eax), %cl /* load single byte */
je L11 /* yes => start loop */
- movb (%eax), %cl /* load single byte */
cmpb %cl, %dl /* is byte == C? */
-
je L2 /* aligned => return pointer */
cmpb $0, %cl /* is byte NUL? */
je L3 /* yes => return NULL */
+ movb 1(%eax), %cl /* load single byte */
incl %eax /* increment pointer */
- cmp $2, %edi /* was alignment == 2? */
- je L11 /* yes => start loop */
-
- movb (%eax), %cl /* load single byte */
cmpb %cl, %dl /* is byte == C? */
-
je L2 /* aligned => return pointer */
cmpb $0, %cl /* is byte NUL? */
diff --git a/sysdeps/i386/i586/strlen.S b/sysdeps/i386/i586/strlen.S
index 15d01947d4..1e17131389 100644
--- a/sysdeps/i386/i586/strlen.S
+++ b/sysdeps/i386/i586/strlen.S
@@ -42,32 +42,31 @@ Boston, MA 02111-1307, USA. */
.text
ENTRY(strlen)
movl 4(%esp), %eax /* get string pointer */
+ movl $3, %edx /* load mask (= 3) */
- movl %eax, %ecx /* duplicate it */
- andl $3, %ecx /* mask alignment bits */
+ andl %eax, %edx /* separate last two bits of address */
- jz L11 /* aligned => start loop */
+ jz L1 /* aligned => start loop */
+ jp L0 /* exactly two bits set */
- cmpb %ch, (%eax) /* is byte NUL? */
+ cmpb %dh, (%eax) /* is byte NUL? */
je L2 /* yes => return */
incl %eax /* increment pointer */
- cmpl $3, %ecx /* was alignment = 3? */
+ xorl $3, %edx /* was alignment = 3? */
- je L11 /* yes => now it is aligned and start loop */
+ jz L1 /* yes => now it is aligned and start loop */
- cmpb %ch, (%eax) /* is byte NUL? */
+L0: cmpb %dh, (%eax) /* is byte NUL? */
je L2 /* yes => return */
incl %eax /* increment pointer */
- cmpl $2, %ecx /* was alignment = 2? */
- je L11 /* yes => now it is aligned and start loop */
-
- cmpb %ch, (%eax) /* is byte NUL? */
+ cmpb %dh, (%eax) /* is byte NUL? */
je L2 /* yes => return */
incl %eax /* increment pointer */
+ xorl %edx, %edx /* We need %edx == 0 for later */
/* We exit the loop if adding MAGIC_BITS to LONGWORD fails to
change any of the hole bits of LONGWORD.
@@ -88,8 +87,9 @@ ENTRY(strlen)
into bit 16. Similarly, there will be a carry into bit
24. If one of bits 24-31 is set, there will be a carry
into bit 32 (=carry flag), so all of the hole bits will
- be changed. */
-L11: xorl %edx, %edx /* We need %edx == 0 for later */
+ be changed.
+
+ Note: %edx == 0 in any case here. */
L1:
movl (%eax), %ecx /* get word (= 4 bytes) in question */