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-rw-r--r--sysdeps/powerpc/powerpc32/power7/memcmp.S1375
1 files changed, 0 insertions, 1375 deletions
diff --git a/sysdeps/powerpc/powerpc32/power7/memcmp.S b/sysdeps/powerpc/powerpc32/power7/memcmp.S
deleted file mode 100644
index 09c9b9bf4d..0000000000
--- a/sysdeps/powerpc/powerpc32/power7/memcmp.S
+++ /dev/null
@@ -1,1375 +0,0 @@
-/* Optimized memcmp implementation for POWER7/PowerPC32.
- Copyright (C) 2010-2017 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
-
- The GNU C Library is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with the GNU C Library; if not, see
- <http://www.gnu.org/licenses/>. */
-
-#include <sysdep.h>
-
-/* int [r3] memcmp (const char *s1 [r3],
- const char *s2 [r4],
- size_t size [r5]) */
-
- .machine power7
-EALIGN (memcmp, 4, 0)
- CALL_MCOUNT
-
-#define rRTN r3
-#define rSTR1 r3 /* first string arg */
-#define rSTR2 r4 /* second string arg */
-#define rN r5 /* max string length */
-#define rWORD1 r6 /* current word in s1 */
-#define rWORD2 r7 /* current word in s2 */
-#define rWORD3 r8 /* next word in s1 */
-#define rWORD4 r9 /* next word in s2 */
-#define rWORD5 r10 /* next word in s1 */
-#define rWORD6 r11 /* next word in s2 */
-#define rWORD7 r30 /* next word in s1 */
-#define rWORD8 r31 /* next word in s2 */
-
- xor r0, rSTR2, rSTR1
- cmplwi cr6, rN, 0
- cmplwi cr1, rN, 12
- clrlwi. r0, r0, 30
- clrlwi r12, rSTR1, 30
- cmplwi cr5, r12, 0
- beq- cr6, L(zeroLength)
- dcbt 0, rSTR1
- dcbt 0, rSTR2
-/* If less than 8 bytes or not aligned, use the unaligned
- byte loop. */
- blt cr1, L(bytealigned)
- stwu 1, -64(r1)
- cfi_adjust_cfa_offset(64)
- stw rWORD8, 48(r1)
- stw rWORD7, 44(r1)
- cfi_offset(rWORD8, (48-64))
- cfi_offset(rWORD7, (44-64))
- bne L(unaligned)
-/* At this point we know both strings have the same alignment and the
- compare length is at least 8 bytes. r12 contains the low order
- 2 bits of rSTR1 and cr5 contains the result of the logical compare
- of r12 to 0. If r12 == 0 then we are already word
- aligned and can perform the word aligned loop.
-
- Otherwise we know the two strings have the same alignment (but not
- yet word aligned). So we force the string addresses to the next lower
- word boundary and special case this first word using shift left to
- eliminate bits preceding the first byte. Since we want to join the
- normal (word aligned) compare loop, starting at the second word,
- we need to adjust the length (rN) and special case the loop
- versioning for the first word. This ensures that the loop count is
- correct and the first word (shifted) is in the expected register pair. */
- .align 4
-L(samealignment):
- clrrwi rSTR1, rSTR1, 2
- clrrwi rSTR2, rSTR2, 2
- beq cr5, L(Waligned)
- add rN, rN, r12
- slwi rWORD6, r12, 3
- srwi r0, rN, 4 /* Divide by 16 */
- andi. r12, rN, 12 /* Get the word remainder */
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD1, 0, rSTR1
- lwbrx rWORD2, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD1, 0(rSTR1)
- lwz rWORD2, 0(rSTR2)
-#endif
- cmplwi cr1, r12, 8
- cmplwi cr7, rN, 16
- clrlwi rN, rN, 30
- beq L(dPs4)
- mtctr r0
- bgt cr1, L(dPs3)
- beq cr1, L(dPs2)
-
-/* Remainder is 4 */
- .align 3
-L(dsP1):
- slw rWORD5, rWORD1, rWORD6
- slw rWORD6, rWORD2, rWORD6
- cmplw cr5, rWORD5, rWORD6
- blt cr7, L(dP1x)
-/* Do something useful in this cycle since we have to branch anyway. */
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD1, 0, rSTR1
- lwbrx rWORD2, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD1, 4(rSTR1)
- lwz rWORD2, 4(rSTR2)
-#endif
- cmplw cr7, rWORD1, rWORD2
- b L(dP1e)
-/* Remainder is 8 */
- .align 4
-L(dPs2):
- slw rWORD5, rWORD1, rWORD6
- slw rWORD6, rWORD2, rWORD6
- cmplw cr6, rWORD5, rWORD6
- blt cr7, L(dP2x)
-/* Do something useful in this cycle since we have to branch anyway. */
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD7, 0, rSTR1
- lwbrx rWORD8, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD7, 4(rSTR1)
- lwz rWORD8, 4(rSTR2)
-#endif
- cmplw cr5, rWORD7, rWORD8
- b L(dP2e)
-/* Remainder is 12 */
- .align 4
-L(dPs3):
- slw rWORD3, rWORD1, rWORD6
- slw rWORD4, rWORD2, rWORD6
- cmplw cr1, rWORD3, rWORD4
- b L(dP3e)
-/* Count is a multiple of 16, remainder is 0 */
- .align 4
-L(dPs4):
- mtctr r0
- slw rWORD1, rWORD1, rWORD6
- slw rWORD2, rWORD2, rWORD6
- cmplw cr7, rWORD1, rWORD2
- b L(dP4e)
-
-/* At this point we know both strings are word aligned and the
- compare length is at least 8 bytes. */
- .align 4
-L(Waligned):
- andi. r12, rN, 12 /* Get the word remainder */
- srwi r0, rN, 4 /* Divide by 16 */
- cmplwi cr1, r12, 8
- cmplwi cr7, rN, 16
- clrlwi rN, rN, 30
- beq L(dP4)
- bgt cr1, L(dP3)
- beq cr1, L(dP2)
-
-/* Remainder is 4 */
- .align 4
-L(dP1):
- mtctr r0
-/* Normally we'd use rWORD7/rWORD8 here, but since we might exit early
- (8-15 byte compare), we want to use only volatile registers. This
- means we can avoid restoring non-volatile registers since we did not
- change any on the early exit path. The key here is the non-early
- exit path only cares about the condition code (cr5), not about which
- register pair was used. */
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD5, 0, rSTR1
- lwbrx rWORD6, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD5, 0(rSTR1)
- lwz rWORD6, 0(rSTR2)
-#endif
- cmplw cr5, rWORD5, rWORD6
- blt cr7, L(dP1x)
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD1, 0, rSTR1
- lwbrx rWORD2, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD1, 4(rSTR1)
- lwz rWORD2, 4(rSTR2)
-#endif
- cmplw cr7, rWORD1, rWORD2
-L(dP1e):
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD3, 0, rSTR1
- lwbrx rWORD4, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD3, 8(rSTR1)
- lwz rWORD4, 8(rSTR2)
-#endif
- cmplw cr1, rWORD3, rWORD4
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD5, 0, rSTR1
- lwbrx rWORD6, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD5, 12(rSTR1)
- lwz rWORD6, 12(rSTR2)
-#endif
- cmplw cr6, rWORD5, rWORD6
- bne cr5, L(dLcr5x)
- bne cr7, L(dLcr7x)
-
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD7, 0, rSTR1
- lwbrx rWORD8, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwzu rWORD7, 16(rSTR1)
- lwzu rWORD8, 16(rSTR2)
-#endif
- bne cr1, L(dLcr1)
- cmplw cr5, rWORD7, rWORD8
- bdnz L(dLoop)
- bne cr6, L(dLcr6)
- lwz rWORD7, 44(r1)
- lwz rWORD8, 48(r1)
- .align 3
-L(dP1x):
- slwi. r12, rN, 3
- bne cr5, L(dLcr5x)
- subfic rN, r12, 32 /* Shift count is 32 - (rN * 8). */
- addi r1, r1, 64
- cfi_adjust_cfa_offset(-64)
- bne L(d00)
- li rRTN, 0
- blr
-
-/* Remainder is 8 */
- .align 4
- cfi_adjust_cfa_offset(64)
-L(dP2):
- mtctr r0
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD5, 0, rSTR1
- lwbrx rWORD6, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD5, 0(rSTR1)
- lwz rWORD6, 0(rSTR2)
-#endif
- cmplw cr6, rWORD5, rWORD6
- blt cr7, L(dP2x)
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD7, 0, rSTR1
- lwbrx rWORD8, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD7, 4(rSTR1)
- lwz rWORD8, 4(rSTR2)
-#endif
- cmplw cr5, rWORD7, rWORD8
-L(dP2e):
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD1, 0, rSTR1
- lwbrx rWORD2, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD1, 8(rSTR1)
- lwz rWORD2, 8(rSTR2)
-#endif
- cmplw cr7, rWORD1, rWORD2
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD3, 0, rSTR1
- lwbrx rWORD4, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD3, 12(rSTR1)
- lwz rWORD4, 12(rSTR2)
-#endif
- cmplw cr1, rWORD3, rWORD4
-#ifndef __LITTLE_ENDIAN__
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#endif
- bne cr6, L(dLcr6)
- bne cr5, L(dLcr5)
- b L(dLoop2)
-/* Again we are on a early exit path (16-23 byte compare), we want to
- only use volatile registers and avoid restoring non-volatile
- registers. */
- .align 4
-L(dP2x):
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD3, 0, rSTR1
- lwbrx rWORD4, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD3, 4(rSTR1)
- lwz rWORD4, 4(rSTR2)
-#endif
- cmplw cr1, rWORD3, rWORD4
- slwi. r12, rN, 3
- bne cr6, L(dLcr6x)
-#ifndef __LITTLE_ENDIAN__
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#endif
- bne cr1, L(dLcr1x)
- subfic rN, r12, 32 /* Shift count is 32 - (rN * 8). */
- addi r1, r1, 64
- cfi_adjust_cfa_offset(-64)
- bne L(d00)
- li rRTN, 0
- blr
-
-/* Remainder is 12 */
- .align 4
- cfi_adjust_cfa_offset(64)
-L(dP3):
- mtctr r0
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD3, 0, rSTR1
- lwbrx rWORD4, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD3, 0(rSTR1)
- lwz rWORD4, 0(rSTR2)
-#endif
- cmplw cr1, rWORD3, rWORD4
-L(dP3e):
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD5, 0, rSTR1
- lwbrx rWORD6, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD5, 4(rSTR1)
- lwz rWORD6, 4(rSTR2)
-#endif
- cmplw cr6, rWORD5, rWORD6
- blt cr7, L(dP3x)
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD7, 0, rSTR1
- lwbrx rWORD8, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD7, 8(rSTR1)
- lwz rWORD8, 8(rSTR2)
-#endif
- cmplw cr5, rWORD7, rWORD8
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD1, 0, rSTR1
- lwbrx rWORD2, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD1, 12(rSTR1)
- lwz rWORD2, 12(rSTR2)
-#endif
- cmplw cr7, rWORD1, rWORD2
-#ifndef __LITTLE_ENDIAN__
- addi rSTR1, rSTR1, 8
- addi rSTR2, rSTR2, 8
-#endif
- bne cr1, L(dLcr1)
- bne cr6, L(dLcr6)
- b L(dLoop1)
-/* Again we are on a early exit path (24-31 byte compare), we want to
- only use volatile registers and avoid restoring non-volatile
- registers. */
- .align 4
-L(dP3x):
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD1, 0, rSTR1
- lwbrx rWORD2, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD1, 8(rSTR1)
- lwz rWORD2, 8(rSTR2)
-#endif
- cmplw cr7, rWORD1, rWORD2
- slwi. r12, rN, 3
- bne cr1, L(dLcr1x)
-#ifndef __LITTLE_ENDIAN__
- addi rSTR1, rSTR1, 8
- addi rSTR2, rSTR2, 8
-#endif
- bne cr6, L(dLcr6x)
- subfic rN, r12, 32 /* Shift count is 32 - (rN * 8). */
- bne cr7, L(dLcr7x)
- addi r1, r1, 64
- cfi_adjust_cfa_offset(-64)
- bne L(d00)
- li rRTN, 0
- blr
-
-/* Count is a multiple of 16, remainder is 0 */
- .align 4
- cfi_adjust_cfa_offset(64)
-L(dP4):
- mtctr r0
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD1, 0, rSTR1
- lwbrx rWORD2, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD1, 0(rSTR1)
- lwz rWORD2, 0(rSTR2)
-#endif
- cmplw cr7, rWORD1, rWORD2
-L(dP4e):
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD3, 0, rSTR1
- lwbrx rWORD4, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD3, 4(rSTR1)
- lwz rWORD4, 4(rSTR2)
-#endif
- cmplw cr1, rWORD3, rWORD4
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD5, 0, rSTR1
- lwbrx rWORD6, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD5, 8(rSTR1)
- lwz rWORD6, 8(rSTR2)
-#endif
- cmplw cr6, rWORD5, rWORD6
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD7, 0, rSTR1
- lwbrx rWORD8, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwzu rWORD7, 12(rSTR1)
- lwzu rWORD8, 12(rSTR2)
-#endif
- cmplw cr5, rWORD7, rWORD8
- bne cr7, L(dLcr7)
- bne cr1, L(dLcr1)
- bdz- L(d24) /* Adjust CTR as we start with +4 */
-/* This is the primary loop */
- .align 4
-L(dLoop):
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD1, 0, rSTR1
- lwbrx rWORD2, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD1, 4(rSTR1)
- lwz rWORD2, 4(rSTR2)
-#endif
- cmplw cr1, rWORD3, rWORD4
- bne cr6, L(dLcr6)
-L(dLoop1):
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD3, 0, rSTR1
- lwbrx rWORD4, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD3, 8(rSTR1)
- lwz rWORD4, 8(rSTR2)
-#endif
- cmplw cr6, rWORD5, rWORD6
- bne cr5, L(dLcr5)
-L(dLoop2):
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD5, 0, rSTR1
- lwbrx rWORD6, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD5, 12(rSTR1)
- lwz rWORD6, 12(rSTR2)
-#endif
- cmplw cr5, rWORD7, rWORD8
- bne cr7, L(dLcr7)
-L(dLoop3):
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD7, 0, rSTR1
- lwbrx rWORD8, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwzu rWORD7, 16(rSTR1)
- lwzu rWORD8, 16(rSTR2)
-#endif
- bne cr1, L(dLcr1)
- cmplw cr7, rWORD1, rWORD2
- bdnz L(dLoop)
-
-L(dL4):
- cmplw cr1, rWORD3, rWORD4
- bne cr6, L(dLcr6)
- cmplw cr6, rWORD5, rWORD6
- bne cr5, L(dLcr5)
- cmplw cr5, rWORD7, rWORD8
-L(d44):
- bne cr7, L(dLcr7)
-L(d34):
- bne cr1, L(dLcr1)
-L(d24):
- bne cr6, L(dLcr6)
-L(d14):
- slwi. r12, rN, 3
- bne cr5, L(dLcr5)
-L(d04):
- lwz rWORD7, 44(r1)
- lwz rWORD8, 48(r1)
- addi r1, r1, 64
- cfi_adjust_cfa_offset(-64)
- subfic rN, r12, 32 /* Shift count is 32 - (rN * 8). */
- beq L(zeroLength)
-/* At this point we have a remainder of 1 to 3 bytes to compare. Since
- we are aligned it is safe to load the whole word, and use
- shift right to eliminate bits beyond the compare length. */
-L(d00):
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD1, 0, rSTR1
- lwbrx rWORD2, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD1, 4(rSTR1)
- lwz rWORD2, 4(rSTR2)
-#endif
- srw rWORD1, rWORD1, rN
- srw rWORD2, rWORD2, rN
- sub rRTN, rWORD1, rWORD2
- blr
-
- .align 4
- cfi_adjust_cfa_offset(64)
-L(dLcr7):
- lwz rWORD7, 44(r1)
- lwz rWORD8, 48(r1)
-L(dLcr7x):
- li rRTN, 1
- addi r1, r1, 64
- cfi_adjust_cfa_offset(-64)
- bgtlr cr7
- li rRTN, -1
- blr
- .align 4
- cfi_adjust_cfa_offset(64)
-L(dLcr1):
- lwz rWORD7, 44(r1)
- lwz rWORD8, 48(r1)
-L(dLcr1x):
- li rRTN, 1
- addi r1, r1, 64
- cfi_adjust_cfa_offset(-64)
- bgtlr cr1
- li rRTN, -1
- blr
- .align 4
- cfi_adjust_cfa_offset(64)
-L(dLcr6):
- lwz rWORD7, 44(r1)
- lwz rWORD8, 48(r1)
-L(dLcr6x):
- li rRTN, 1
- addi r1, r1, 64
- cfi_adjust_cfa_offset(-64)
- bgtlr cr6
- li rRTN, -1
- blr
- .align 4
- cfi_adjust_cfa_offset(64)
-L(dLcr5):
- lwz rWORD7, 44(r1)
- lwz rWORD8, 48(r1)
-L(dLcr5x):
- li rRTN, 1
- addi r1, r1, 64
- cfi_adjust_cfa_offset(-64)
- bgtlr cr5
- li rRTN, -1
- blr
-
- .align 4
-L(bytealigned):
- mtctr rN
-
-/* We need to prime this loop. This loop is swing modulo scheduled
- to avoid pipe delays. The dependent instruction latencies (load to
- compare to conditional branch) is 2 to 3 cycles. In this loop each
- dispatch group ends in a branch and takes 1 cycle. Effectively
- the first iteration of the loop only serves to load operands and
- branches based on compares are delayed until the next loop.
-
- So we must precondition some registers and condition codes so that
- we don't exit the loop early on the first iteration. */
-
- lbz rWORD1, 0(rSTR1)
- lbz rWORD2, 0(rSTR2)
- bdz L(b11)
- cmplw cr7, rWORD1, rWORD2
- lbz rWORD3, 1(rSTR1)
- lbz rWORD4, 1(rSTR2)
- bdz L(b12)
- cmplw cr1, rWORD3, rWORD4
- lbzu rWORD5, 2(rSTR1)
- lbzu rWORD6, 2(rSTR2)
- bdz L(b13)
- .align 4
-L(bLoop):
- lbzu rWORD1, 1(rSTR1)
- lbzu rWORD2, 1(rSTR2)
- bne cr7, L(bLcr7)
-
- cmplw cr6, rWORD5, rWORD6
- bdz L(b3i)
-
- lbzu rWORD3, 1(rSTR1)
- lbzu rWORD4, 1(rSTR2)
- bne cr1, L(bLcr1)
-
- cmplw cr7, rWORD1, rWORD2
- bdz L(b2i)
-
- lbzu rWORD5, 1(rSTR1)
- lbzu rWORD6, 1(rSTR2)
- bne cr6, L(bLcr6)
-
- cmplw cr1, rWORD3, rWORD4
- bdnz L(bLoop)
-
-/* We speculatively loading bytes before we have tested the previous
- bytes. But we must avoid overrunning the length (in the ctr) to
- prevent these speculative loads from causing a segfault. In this
- case the loop will exit early (before the all pending bytes are
- tested. In this case we must complete the pending operations
- before returning. */
-L(b1i):
- bne cr7, L(bLcr7)
- bne cr1, L(bLcr1)
- b L(bx56)
- .align 4
-L(b2i):
- bne cr6, L(bLcr6)
- bne cr7, L(bLcr7)
- b L(bx34)
- .align 4
-L(b3i):
- bne cr1, L(bLcr1)
- bne cr6, L(bLcr6)
- b L(bx12)
- .align 4
-L(bLcr7):
- li rRTN, 1
- bgtlr cr7
- li rRTN, -1
- blr
-L(bLcr1):
- li rRTN, 1
- bgtlr cr1
- li rRTN, -1
- blr
-L(bLcr6):
- li rRTN, 1
- bgtlr cr6
- li rRTN, -1
- blr
-
-L(b13):
- bne cr7, L(bx12)
- bne cr1, L(bx34)
-L(bx56):
- sub rRTN, rWORD5, rWORD6
- blr
- nop
-L(b12):
- bne cr7, L(bx12)
-L(bx34):
- sub rRTN, rWORD3, rWORD4
- blr
-L(b11):
-L(bx12):
- sub rRTN, rWORD1, rWORD2
- blr
- .align 4
-L(zeroLength):
- li rRTN, 0
- blr
-
- .align 4
-/* At this point we know the strings have different alignment and the
- compare length is at least 8 bytes. r12 contains the low order
- 2 bits of rSTR1 and cr5 contains the result of the logical compare
- of r12 to 0. If r12 == 0 then rStr1 is word aligned and can
- perform the Wunaligned loop.
-
- Otherwise we know that rSTR1 is not already word aligned yet.
- So we can force the string addresses to the next lower word
- boundary and special case this first word using shift left to
- eliminate bits preceding the first byte. Since we want to join the
- normal (Wualigned) compare loop, starting at the second word,
- we need to adjust the length (rN) and special case the loop
- versioning for the first W. This ensures that the loop count is
- correct and the first W (shifted) is in the expected resister pair. */
-#define rSHL r29 /* Unaligned shift left count. */
-#define rSHR r28 /* Unaligned shift right count. */
-#define rWORD8_SHIFT r27 /* Left rotation temp for rWORD2. */
-#define rWORD2_SHIFT r26 /* Left rotation temp for rWORD4. */
-#define rWORD4_SHIFT r25 /* Left rotation temp for rWORD6. */
-#define rWORD6_SHIFT r24 /* Left rotation temp for rWORD8. */
- cfi_adjust_cfa_offset(64)
-L(unaligned):
- stw rSHL, 40(r1)
- cfi_offset(rSHL, (40-64))
- clrlwi rSHL, rSTR2, 30
- stw rSHR, 36(r1)
- cfi_offset(rSHR, (36-64))
- beq cr5, L(Wunaligned)
- stw rWORD8_SHIFT, 32(r1)
- cfi_offset(rWORD8_SHIFT, (32-64))
-/* Adjust the logical start of rSTR2 to compensate for the extra bits
- in the 1st rSTR1 W. */
- sub rWORD8_SHIFT, rSTR2, r12
-/* But do not attempt to address the W before that W that contains
- the actual start of rSTR2. */
- clrrwi rSTR2, rSTR2, 2
- stw rWORD2_SHIFT, 28(r1)
-/* Compute the left/right shift counts for the unaligned rSTR2,
- compensating for the logical (W aligned) start of rSTR1. */
- clrlwi rSHL, rWORD8_SHIFT, 30
- clrrwi rSTR1, rSTR1, 2
- stw rWORD4_SHIFT, 24(r1)
- slwi rSHL, rSHL, 3
- cmplw cr5, rWORD8_SHIFT, rSTR2
- add rN, rN, r12
- slwi rWORD6, r12, 3
- stw rWORD6_SHIFT, 20(r1)
- cfi_offset(rWORD2_SHIFT, (28-64))
- cfi_offset(rWORD4_SHIFT, (24-64))
- cfi_offset(rWORD6_SHIFT, (20-64))
- subfic rSHR, rSHL, 32
- srwi r0, rN, 4 /* Divide by 16 */
- andi. r12, rN, 12 /* Get the W remainder */
-/* We normally need to load 2 Ws to start the unaligned rSTR2, but in
- this special case those bits may be discarded anyway. Also we
- must avoid loading a W where none of the bits are part of rSTR2 as
- this may cross a page boundary and cause a page fault. */
- li rWORD8, 0
- blt cr5, L(dus0)
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD8, 0, rSTR2
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD8, 0(rSTR2)
- addi rSTR2, rSTR2, 4
-#endif
- slw rWORD8, rWORD8, rSHL
-
-L(dus0):
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD1, 0, rSTR1
- lwbrx rWORD2, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD1, 0(rSTR1)
- lwz rWORD2, 0(rSTR2)
-#endif
- cmplwi cr1, r12, 8
- cmplwi cr7, rN, 16
- srw r12, rWORD2, rSHR
- clrlwi rN, rN, 30
- beq L(duPs4)
- mtctr r0
- or rWORD8, r12, rWORD8
- bgt cr1, L(duPs3)
- beq cr1, L(duPs2)
-
-/* Remainder is 4 */
- .align 4
-L(dusP1):
- slw rWORD8_SHIFT, rWORD2, rSHL
- slw rWORD7, rWORD1, rWORD6
- slw rWORD8, rWORD8, rWORD6
- bge cr7, L(duP1e)
-/* At this point we exit early with the first word compare
- complete and remainder of 0 to 3 bytes. See L(du14) for details on
- how we handle the remaining bytes. */
- cmplw cr5, rWORD7, rWORD8
- slwi. rN, rN, 3
- bne cr5, L(duLcr5)
- cmplw cr7, rN, rSHR
- beq L(duZeroReturn)
- li r0, 0
- ble cr7, L(dutrim)
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD2, 0, rSTR2
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD2, 4(rSTR2)
-#endif
- srw r0, rWORD2, rSHR
- b L(dutrim)
-/* Remainder is 8 */
- .align 4
-L(duPs2):
- slw rWORD6_SHIFT, rWORD2, rSHL
- slw rWORD5, rWORD1, rWORD6
- slw rWORD6, rWORD8, rWORD6
- b L(duP2e)
-/* Remainder is 12 */
- .align 4
-L(duPs3):
- slw rWORD4_SHIFT, rWORD2, rSHL
- slw rWORD3, rWORD1, rWORD6
- slw rWORD4, rWORD8, rWORD6
- b L(duP3e)
-/* Count is a multiple of 16, remainder is 0 */
- .align 4
-L(duPs4):
- mtctr r0
- or rWORD8, r12, rWORD8
- slw rWORD2_SHIFT, rWORD2, rSHL
- slw rWORD1, rWORD1, rWORD6
- slw rWORD2, rWORD8, rWORD6
- b L(duP4e)
-
-/* At this point we know rSTR1 is word aligned and the
- compare length is at least 8 bytes. */
- .align 4
-L(Wunaligned):
- stw rWORD8_SHIFT, 32(r1)
- clrrwi rSTR2, rSTR2, 2
- stw rWORD2_SHIFT, 28(r1)
- srwi r0, rN, 4 /* Divide by 16 */
- stw rWORD4_SHIFT, 24(r1)
- andi. r12, rN, 12 /* Get the W remainder */
- stw rWORD6_SHIFT, 20(r1)
- cfi_offset(rWORD8_SHIFT, (32-64))
- cfi_offset(rWORD2_SHIFT, (28-64))
- cfi_offset(rWORD4_SHIFT, (24-64))
- cfi_offset(rWORD6_SHIFT, (20-64))
- slwi rSHL, rSHL, 3
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD6, 0, rSTR2
- addi rSTR2, rSTR2, 4
- lwbrx rWORD8, 0, rSTR2
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD6, 0(rSTR2)
- lwzu rWORD8, 4(rSTR2)
-#endif
- cmplwi cr1, r12, 8
- cmplwi cr7, rN, 16
- clrlwi rN, rN, 30
- subfic rSHR, rSHL, 32
- slw rWORD6_SHIFT, rWORD6, rSHL
- beq L(duP4)
- mtctr r0
- bgt cr1, L(duP3)
- beq cr1, L(duP2)
-
-/* Remainder is 4 */
- .align 4
-L(duP1):
- srw r12, rWORD8, rSHR
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD7, 0, rSTR1
- addi rSTR1, rSTR1, 4
-#else
- lwz rWORD7, 0(rSTR1)
-#endif
- slw rWORD8_SHIFT, rWORD8, rSHL
- or rWORD8, r12, rWORD6_SHIFT
- blt cr7, L(duP1x)
-L(duP1e):
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD1, 0, rSTR1
- lwbrx rWORD2, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD1, 4(rSTR1)
- lwz rWORD2, 4(rSTR2)
-#endif
- cmplw cr5, rWORD7, rWORD8
- srw r0, rWORD2, rSHR
- slw rWORD2_SHIFT, rWORD2, rSHL
- or rWORD2, r0, rWORD8_SHIFT
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD3, 0, rSTR1
- lwbrx rWORD4, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD3, 8(rSTR1)
- lwz rWORD4, 8(rSTR2)
-#endif
- cmplw cr7, rWORD1, rWORD2
- srw r12, rWORD4, rSHR
- slw rWORD4_SHIFT, rWORD4, rSHL
- bne cr5, L(duLcr5)
- or rWORD4, r12, rWORD2_SHIFT
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD5, 0, rSTR1
- lwbrx rWORD6, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD5, 12(rSTR1)
- lwz rWORD6, 12(rSTR2)
-#endif
- cmplw cr1, rWORD3, rWORD4
- srw r0, rWORD6, rSHR
- slw rWORD6_SHIFT, rWORD6, rSHL
- bne cr7, L(duLcr7)
- or rWORD6, r0, rWORD4_SHIFT
- cmplw cr6, rWORD5, rWORD6
- b L(duLoop3)
- .align 4
-/* At this point we exit early with the first word compare
- complete and remainder of 0 to 3 bytes. See L(du14) for details on
- how we handle the remaining bytes. */
-L(duP1x):
- cmplw cr5, rWORD7, rWORD8
- slwi. rN, rN, 3
- bne cr5, L(duLcr5)
- cmplw cr7, rN, rSHR
- beq L(duZeroReturn)
- li r0, 0
- ble cr7, L(dutrim)
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD2, 0, rSTR2
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD2, 8(rSTR2)
-#endif
- srw r0, rWORD2, rSHR
- b L(dutrim)
-/* Remainder is 8 */
- .align 4
-L(duP2):
- srw r0, rWORD8, rSHR
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD5, 0, rSTR1
- addi rSTR1, rSTR1, 4
-#else
- lwz rWORD5, 0(rSTR1)
-#endif
- or rWORD6, r0, rWORD6_SHIFT
- slw rWORD6_SHIFT, rWORD8, rSHL
-L(duP2e):
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD7, 0, rSTR1
- lwbrx rWORD8, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD7, 4(rSTR1)
- lwz rWORD8, 4(rSTR2)
-#endif
- cmplw cr6, rWORD5, rWORD6
- srw r12, rWORD8, rSHR
- slw rWORD8_SHIFT, rWORD8, rSHL
- or rWORD8, r12, rWORD6_SHIFT
- blt cr7, L(duP2x)
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD1, 0, rSTR1
- lwbrx rWORD2, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD1, 8(rSTR1)
- lwz rWORD2, 8(rSTR2)
-#endif
- cmplw cr5, rWORD7, rWORD8
- bne cr6, L(duLcr6)
- srw r0, rWORD2, rSHR
- slw rWORD2_SHIFT, rWORD2, rSHL
- or rWORD2, r0, rWORD8_SHIFT
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD3, 0, rSTR1
- lwbrx rWORD4, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD3, 12(rSTR1)
- lwz rWORD4, 12(rSTR2)
-#endif
- cmplw cr7, rWORD1, rWORD2
- bne cr5, L(duLcr5)
- srw r12, rWORD4, rSHR
- slw rWORD4_SHIFT, rWORD4, rSHL
- or rWORD4, r12, rWORD2_SHIFT
-#ifndef __LITTLE_ENDIAN__
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#endif
- cmplw cr1, rWORD3, rWORD4
- b L(duLoop2)
- .align 4
-L(duP2x):
- cmplw cr5, rWORD7, rWORD8
-#ifndef __LITTLE_ENDIAN__
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#endif
- bne cr6, L(duLcr6)
- slwi. rN, rN, 3
- bne cr5, L(duLcr5)
- cmplw cr7, rN, rSHR
- beq L(duZeroReturn)
- li r0, 0
- ble cr7, L(dutrim)
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD2, 0, rSTR2
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD2, 4(rSTR2)
-#endif
- srw r0, rWORD2, rSHR
- b L(dutrim)
-
-/* Remainder is 12 */
- .align 4
-L(duP3):
- srw r12, rWORD8, rSHR
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD3, 0, rSTR1
- addi rSTR1, rSTR1, 4
-#else
- lwz rWORD3, 0(rSTR1)
-#endif
- slw rWORD4_SHIFT, rWORD8, rSHL
- or rWORD4, r12, rWORD6_SHIFT
-L(duP3e):
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD5, 0, rSTR1
- lwbrx rWORD6, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD5, 4(rSTR1)
- lwz rWORD6, 4(rSTR2)
-#endif
- cmplw cr1, rWORD3, rWORD4
- srw r0, rWORD6, rSHR
- slw rWORD6_SHIFT, rWORD6, rSHL
- or rWORD6, r0, rWORD4_SHIFT
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD7, 0, rSTR1
- lwbrx rWORD8, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD7, 8(rSTR1)
- lwz rWORD8, 8(rSTR2)
-#endif
- cmplw cr6, rWORD5, rWORD6
- bne cr1, L(duLcr1)
- srw r12, rWORD8, rSHR
- slw rWORD8_SHIFT, rWORD8, rSHL
- or rWORD8, r12, rWORD6_SHIFT
- blt cr7, L(duP3x)
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD1, 0, rSTR1
- lwbrx rWORD2, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD1, 12(rSTR1)
- lwz rWORD2, 12(rSTR2)
-#endif
- cmplw cr5, rWORD7, rWORD8
- bne cr6, L(duLcr6)
- srw r0, rWORD2, rSHR
- slw rWORD2_SHIFT, rWORD2, rSHL
- or rWORD2, r0, rWORD8_SHIFT
-#ifndef __LITTLE_ENDIAN__
- addi rSTR1, rSTR1, 8
- addi rSTR2, rSTR2, 8
-#endif
- cmplw cr7, rWORD1, rWORD2
- b L(duLoop1)
- .align 4
-L(duP3x):
-#ifndef __LITTLE_ENDIAN__
- addi rSTR1, rSTR1, 8
- addi rSTR2, rSTR2, 8
-#endif
-#if 0
-/* Huh? We've already branched on cr1! */
- bne cr1, L(duLcr1)
-#endif
- cmplw cr5, rWORD7, rWORD8
- bne cr6, L(duLcr6)
- slwi. rN, rN, 3
- bne cr5, L(duLcr5)
- cmplw cr7, rN, rSHR
- beq L(duZeroReturn)
- li r0, 0
- ble cr7, L(dutrim)
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD2, 0, rSTR2
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD2, 4(rSTR2)
-#endif
- srw r0, rWORD2, rSHR
- b L(dutrim)
-
-/* Count is a multiple of 16, remainder is 0 */
- .align 4
-L(duP4):
- mtctr r0
- srw r0, rWORD8, rSHR
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD1, 0, rSTR1
- addi rSTR1, rSTR1, 4
-#else
- lwz rWORD1, 0(rSTR1)
-#endif
- slw rWORD2_SHIFT, rWORD8, rSHL
- or rWORD2, r0, rWORD6_SHIFT
-L(duP4e):
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD3, 0, rSTR1
- lwbrx rWORD4, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD3, 4(rSTR1)
- lwz rWORD4, 4(rSTR2)
-#endif
- cmplw cr7, rWORD1, rWORD2
- srw r12, rWORD4, rSHR
- slw rWORD4_SHIFT, rWORD4, rSHL
- or rWORD4, r12, rWORD2_SHIFT
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD5, 0, rSTR1
- lwbrx rWORD6, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD5, 8(rSTR1)
- lwz rWORD6, 8(rSTR2)
-#endif
- cmplw cr1, rWORD3, rWORD4
- bne cr7, L(duLcr7)
- srw r0, rWORD6, rSHR
- slw rWORD6_SHIFT, rWORD6, rSHL
- or rWORD6, r0, rWORD4_SHIFT
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD7, 0, rSTR1
- lwbrx rWORD8, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwzu rWORD7, 12(rSTR1)
- lwzu rWORD8, 12(rSTR2)
-#endif
- cmplw cr6, rWORD5, rWORD6
- bne cr1, L(duLcr1)
- srw r12, rWORD8, rSHR
- slw rWORD8_SHIFT, rWORD8, rSHL
- or rWORD8, r12, rWORD6_SHIFT
- cmplw cr5, rWORD7, rWORD8
- bdz L(du24) /* Adjust CTR as we start with +4 */
-/* This is the primary loop */
- .align 4
-L(duLoop):
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD1, 0, rSTR1
- lwbrx rWORD2, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD1, 4(rSTR1)
- lwz rWORD2, 4(rSTR2)
-#endif
- cmplw cr1, rWORD3, rWORD4
- bne cr6, L(duLcr6)
- srw r0, rWORD2, rSHR
- slw rWORD2_SHIFT, rWORD2, rSHL
- or rWORD2, r0, rWORD8_SHIFT
-L(duLoop1):
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD3, 0, rSTR1
- lwbrx rWORD4, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD3, 8(rSTR1)
- lwz rWORD4, 8(rSTR2)
-#endif
- cmplw cr6, rWORD5, rWORD6
- bne cr5, L(duLcr5)
- srw r12, rWORD4, rSHR
- slw rWORD4_SHIFT, rWORD4, rSHL
- or rWORD4, r12, rWORD2_SHIFT
-L(duLoop2):
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD5, 0, rSTR1
- lwbrx rWORD6, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD5, 12(rSTR1)
- lwz rWORD6, 12(rSTR2)
-#endif
- cmplw cr5, rWORD7, rWORD8
- bne cr7, L(duLcr7)
- srw r0, rWORD6, rSHR
- slw rWORD6_SHIFT, rWORD6, rSHL
- or rWORD6, r0, rWORD4_SHIFT
-L(duLoop3):
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD7, 0, rSTR1
- lwbrx rWORD8, 0, rSTR2
- addi rSTR1, rSTR1, 4
- addi rSTR2, rSTR2, 4
-#else
- lwzu rWORD7, 16(rSTR1)
- lwzu rWORD8, 16(rSTR2)
-#endif
- cmplw cr7, rWORD1, rWORD2
- bne cr1, L(duLcr1)
- srw r12, rWORD8, rSHR
- slw rWORD8_SHIFT, rWORD8, rSHL
- or rWORD8, r12, rWORD6_SHIFT
- bdnz L(duLoop)
-
-L(duL4):
-#if 0
-/* Huh? We've already branched on cr1! */
- bne cr1, L(duLcr1)
-#endif
- cmplw cr1, rWORD3, rWORD4
- bne cr6, L(duLcr6)
- cmplw cr6, rWORD5, rWORD6
- bne cr5, L(duLcr5)
- cmplw cr5, rWORD7, rWORD8
-L(du44):
- bne cr7, L(duLcr7)
-L(du34):
- bne cr1, L(duLcr1)
-L(du24):
- bne cr6, L(duLcr6)
-L(du14):
- slwi. rN, rN, 3
- bne cr5, L(duLcr5)
-/* At this point we have a remainder of 1 to 3 bytes to compare. We use
- shift right to eliminate bits beyond the compare length.
- This allows the use of word subtract to compute the final result.
-
- However it may not be safe to load rWORD2 which may be beyond the
- string length. So we compare the bit length of the remainder to
- the right shift count (rSHR). If the bit count is less than or equal
- we do not need to load rWORD2 (all significant bits are already in
- rWORD8_SHIFT). */
- cmplw cr7, rN, rSHR
- beq L(duZeroReturn)
- li r0, 0
- ble cr7, L(dutrim)
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD2, 0, rSTR2
- addi rSTR2, rSTR2, 4
-#else
- lwz rWORD2, 4(rSTR2)
-#endif
- srw r0, rWORD2, rSHR
- .align 4
-L(dutrim):
-#ifdef __LITTLE_ENDIAN__
- lwbrx rWORD1, 0, rSTR1
-#else
- lwz rWORD1, 4(rSTR1)
-#endif
- lwz rWORD8, 48(r1)
- subfic rN, rN, 32 /* Shift count is 32 - (rN * 8). */
- or rWORD2, r0, rWORD8_SHIFT
- lwz rWORD7, 44(r1)
- lwz rSHL, 40(r1)
- srw rWORD1, rWORD1, rN
- srw rWORD2, rWORD2, rN
- lwz rSHR, 36(r1)
- lwz rWORD8_SHIFT, 32(r1)
- sub rRTN, rWORD1, rWORD2
- b L(dureturn26)
- .align 4
-L(duLcr7):
- lwz rWORD8, 48(r1)
- lwz rWORD7, 44(r1)
- li rRTN, 1
- bgt cr7, L(dureturn29)
- lwz rSHL, 40(r1)
- lwz rSHR, 36(r1)
- li rRTN, -1
- b L(dureturn27)
- .align 4
-L(duLcr1):
- lwz rWORD8, 48(r1)
- lwz rWORD7, 44(r1)
- li rRTN, 1
- bgt cr1, L(dureturn29)
- lwz rSHL, 40(r1)
- lwz rSHR, 36(r1)
- li rRTN, -1
- b L(dureturn27)
- .align 4
-L(duLcr6):
- lwz rWORD8, 48(r1)
- lwz rWORD7, 44(r1)
- li rRTN, 1
- bgt cr6, L(dureturn29)
- lwz rSHL, 40(r1)
- lwz rSHR, 36(r1)
- li rRTN, -1
- b L(dureturn27)
- .align 4
-L(duLcr5):
- lwz rWORD8, 48(r1)
- lwz rWORD7, 44(r1)
- li rRTN, 1
- bgt cr5, L(dureturn29)
- lwz rSHL, 40(r1)
- lwz rSHR, 36(r1)
- li rRTN, -1
- b L(dureturn27)
- .align 3
-L(duZeroReturn):
- li rRTN, 0
- .align 4
-L(dureturn):
- lwz rWORD8, 48(r1)
- lwz rWORD7, 44(r1)
-L(dureturn29):
- lwz rSHL, 40(r1)
- lwz rSHR, 36(r1)
-L(dureturn27):
- lwz rWORD8_SHIFT, 32(r1)
-L(dureturn26):
- lwz rWORD2_SHIFT, 28(r1)
-L(dureturn25):
- lwz rWORD4_SHIFT, 24(r1)
- lwz rWORD6_SHIFT, 20(r1)
- addi r1, r1, 64
- cfi_adjust_cfa_offset(-64)
- blr
-END (memcmp)
-
-libc_hidden_builtin_def (memcmp)
-weak_alias (memcmp, bcmp)