@@ -25,122 +25,96 @@
/* int [r3] strcmp (const char *s1 [r3], const char *s2 [r4]) */
+ .machine power7
EALIGN (strcmp, 4, 0)
CALL_MCOUNT 2
or r9, r3, r4
rldicl. r10, r9, 0, 61 /* are s1 and s2 8 byte aligned..? */
bne cr0, L(process_unaligned_bytes)
+ li r5, 0
+ .align 4
/* process input parameters on double word aligned boundary */
- ld r9, 0(r4) /* load s2 at offset=0 */
- li r10, 0 /* load mask=0 */
- cmpb r10, r9, r10 /* compare bytes at s2 with mask */
- cmpdi cr7, r10, 0 /* is NULL found ..? is end of string HIT */
- bne cr7, L(process_unaligned_bytes) /* process byte by byte */
-
- ld r10, 0(r3) /* load s1 at offset=0 */
- li r8, 0 /* load mask=0 */
- cmpb r8, r10, r8 /* compare bytes at s1 with mask */
- cmpdi cr7, r8, 0 /* is NULL found ..? is end of string HIT */
- bne cr7, L(process_unaligned_bytes) /* process byte by byte */
-
-/*s1 and s2 does not contain NULL now , so compare all 8 bytes in a GO */
- cmpb r9, r10, r9 /* compare s1 and s2 */
- cmpdi cr7, r9, -1 /* compare result with 0xFFFFFFFFFFFFFFFF */
- bne cr7, L(process_unaligned_bytes) /* s1,s2 mismatch found */
-
- addi r5, r3, 8 /* save next offset of s2 */
- addi r11, r4, 8 /* save next offset of s1 */
- ld r8, 8(r4) /* load s2 at offset=8 */
- li r9, 0 /* load mask=0 */
- cmpb r9, r8, r9 /* compare bytes at s2 with mask */
- cmpdi cr7, r9, 0 /* NULL found ..? */
- bne cr7, L(processBytes)/* update input and process bytes one by one */
-
- mr r9, r4 /* save s2 */
- li r10, 0 /* load mask=0 */
-
- ld r7, 8(r3) /* load s1 at offset=8 */
- cmpb r6, r7, r10 /* compare bytes at s1 with mask */
- cmpdi cr7, r6, 0 /* is NULL found */
- bne cr7, L(processBytes)/* mismatch, so process one by one */
-
L(unrollDword):
- cmpb r8, r7, r8 /* compare s1 and s2 */
- cmpdi cr7, r8, -1 /* compare result with 0xFFFFFFFFFFFFFFFF */
- bne cr7, L(processBytes)/* mismatch with s1 and s2 */
-
- addi r5, r3, 16 /* save offset=16 of s1 */
- addi r4, r9, 16 /* save offset=16 of s2 */
- ld r8, 16(r9) /* load s2 at offset=16 */
- cmpb r7, r8, r10 /* compare bytes at s2 with mask */
- cmpdi cr7, r7, 0 /* NULL found ..? */
- bne cr7, L(update2processBytes)
-
- ld r7, 16(r3) /* load s1 at offset=16 */
- cmpb r6, r7, r10 /* check s1 for end of string */
- cmpdi cr7, r6, 0 /* end of s1 ?,then handle byte by byte */
- bne 7,L(update2processBytes)
-
- cmpb r8, r7, r8 /* compare s1 and s2 double words */
- cmpdi cr7, r8, -1 /* compare results with 0xFFFFFFFFFFFFFFFF */
- bne cr7,L(update2processBytes)
-
- addi r5, r3, 24 /* update s1 to offset=24 */
- addi r4, r9, 24 /* update s2 to offset=24 */
-
- ld r8, 24(r9) /* load s2 */
- cmpb r7, r8, r10 /* compare s2 for NULL */
- cmpdi cr7, r7, 0 /* verify if s2 is ending now */
- bne cr7,L(update2processBytes)
-
- ld r7, 24(r3) /* load s1 at offset=24 */
- cmpb r6, r7, r10 /* verify for NULL */
- cmpdi cr7, r6, 0 /* is NULL found */
- bne cr7, L(update2processBytes)
-
- cmpb r8, r7, r8 /* compare s1 and s2 */
- cmpdi cr7, r8, -1 /* are s1 and s2 same ..? */
- bne cr7, L(update2processBytes)
-
- addi r7, r9, 32 /* update s2 to next double word */
- addi r3, r3, 32 /* update s1 to next double word */
-
- ld r8, 32(r9) /* load s2 */
- mr r4, r7 /* save s2 */
- cmpb r6, r8, r10 /* compare s2 with NULL */
- cmpdi cr7, r6, 0 /* end of s2 ..? */
- bne cr7, L(process_unaligned_bytes)
-
- ld r6, 0(r3) /* load and compare s1 for NULL */
- cmpb r5, r6, r10
- cmpdi cr7, r5, 0
- bne cr7, L(process_unaligned_bytes)
-
- cmpb r8, r6, r8 /* compare s1 and s2 */
- cmpdi cr7, r8, -1
- bne cr7, L(process_unaligned_bytes)
-
- addi r5, r3, 8 /* increment s1 and d2 here */
- addi r11, r9, 40
-
- ld r8, 40(r9) /* process s2 now */
- cmpb r9, r8, r10
- cmpdi cr7, r9, 0
- bne cr7, L(processBytes)
-
- mr r9, r7
- ld r7, 8(r3) /* process s1 now */
- cmpb r6, r7, r10
- cmpdi cr7, r6, 0
- beq cr7, L(unrollDword) /* unroll to compare s1 and s2 */
-
-L(processBytes):
- mr r4, r11 /* update input params */
- mr r3, r5
-
- .p2align 4
+ ld r8,0(r3)
+ ld r10,0(r4)
+ cmpb r7,r8,r5
+ cmpdi cr7,r7,0
+ mr r9,r7
+ bne cr7,L(null_found)
+ cmpld cr7,r8,r10
+ bne cr7,L(different)
+
+ ld r8,8(r3)
+ ld r10,8(r4)
+ cmpb r7,r8,r5
+ cmpdi cr7,r7,0
+ mr r9,r7
+ bne cr7,L(null_found)
+ cmpld cr7,r8,r10
+ bne cr7,L(different)
+
+ ld r8,16(r3)
+ ld r10,16(r4)
+ cmpb r7,r8,r5
+ cmpdi cr7,r7,0
+ mr r9,r7
+ bne cr7,L(null_found)
+ cmpld cr7,r8,r10
+ bne cr7,L(different)
+
+ ld r8,24(r3)
+ ld r10,24(r4)
+ cmpb r7,r8,r5
+ cmpdi cr7,r7,0
+ mr r9,r7
+ bne cr7,L(null_found)
+ cmpld cr7,r8,r10
+ bne cr7,L(different)
+
+ addi r3, r3, 32
+ addi r4, r4, 32
+ beq cr7, L(unrollDword)
+
+ .align 4
+L(null_found):
+#ifdef __LITTLE_ENDIAN__
+ neg r7,r9
+ and r9,r9,r7
+ li r7,-1
+ cntlzd r9,r9
+ subfic r9,r9,71
+ sld r9,r7,r9
+#else
+ cntlzd r9,r9
+ li r7,-1
+ addi r9,r9,8
+ srd r9,r7,r9
+#endif
+ or r8,r8,r9
+ or r10,r10,r9
+
+L(different):
+ cmpb r9,r8,r10
+#ifdef __LITTLE_ENDIAN__
+ addi r7,r9,1
+ andc r9,r7,r9
+ cntlzd r9,r9
+ subfic r9,r9,63
+#else
+ not r9,r9
+ cntlzd r9,r9
+ subfic r9,r9,56
+#endif
+ srd r3,r8,r9
+ srd r10,r10,r9
+ rldicl r10,r10,0,56
+ rldicl r3,r3,0,56
+ subf r3,r10,r3
+ blr
+
+ .align 4
L(process_unaligned_bytes):
lbz r9, 0(r3) /* load byte from s1 */
lbz r10, 0(r4) /* load byte from s2 */
@@ -172,24 +146,19 @@ L(process_unaligned_bytes):
addi r4, r4, 4 /* increment s2 by unroll factor */
beq cr6, L(process_unaligned_bytes) /* unroll byte processing */
- .p2align 4
+ .align 4
L(ComputeDiff):
extsw r9, r9
subf r10, r10, r9 /* compute s1 - s2 */
extsw r3, r10
blr /* return */
- .p2align 4
+ .align 4
L(diffOfNULL):
li r9, 0
subf r10, r10, r9 /* compute s1 - s2 */
extsw r3, r10 /* sign extend result */
blr /* return */
- .p2align 4
-L(update2processBytes):
- mr r3, r5 /* update and proceed */
- b L(process_unaligned_bytes)
-
END (strcmp)
libc_hidden_builtin_def (strcmp)