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-rw-r--r--ports/sysdeps/powerpc/powerpc32/405/memcmp.S130
1 files changed, 130 insertions, 0 deletions
diff --git a/ports/sysdeps/powerpc/powerpc32/405/memcmp.S b/ports/sysdeps/powerpc/powerpc32/405/memcmp.S
new file mode 100644
index 0000000000..b9628b1941
--- /dev/null
+++ b/ports/sysdeps/powerpc/powerpc32/405/memcmp.S
@@ -0,0 +1,130 @@
+/* Optimized memcmp implementation for PowerPC476.
+   Copyright (C) 2010 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>
+#include <bp-sym.h>
+#include <bp-asm.h>
+
+/* memcmp
+
+       r3:source1 address, return equality
+       r4:source2 address
+       r5:byte count
+
+       Check 2 words from src1 and src2. If unequal jump to end and
+       return src1 > src2 or src1 < src2.
+       If count = zero check bytes before zero counter and then jump to end and
+       return src1 > src2, src1 < src2 or src1 = src2.
+       If src1 = src2 and no null, repeat. */
+
+EALIGN (BP_SYM (memcmp), 5, 0)
+       srwi.   r6,r5,5
+       beq     L(preword2_count_loop)
+       mtctr   r6
+       clrlwi  r5,r5,27
+
+L(word8_compare_loop):
+       lwz     r10,0(r3)
+       lwz     r6,4(r3)
+       lwz     r8,0(r4)
+       lwz     r9,4(r4)
+       cmplw   cr5,r8,r10
+       cmplw   cr1,r9,r6
+       bne     cr5,L(st2)
+       bne     cr1,L(st1)
+       lwz     r10,8(r3)
+       lwz     r6,12(r3)
+       lwz     r8,8(r4)
+       lwz     r9,12(r4)
+       cmplw   cr5,r8,r10
+       cmplw   cr1,r9,r6
+       bne     cr5,L(st2)
+       bne     cr1,L(st1)
+       lwz     r10,16(r3)
+       lwz     r6,20(r3)
+       lwz     r8,16(r4)
+       lwz     r9,20(r4)
+       cmplw   cr5,r8,r10
+       cmplw   cr1,r9,r6
+       bne     cr5,L(st2)
+       bne     cr1,L(st1)
+       lwz     r10,24(r3)
+       lwz     r6,28(r3)
+       addi    r3,r3,0x20
+       lwz     r8,24(r4)
+       lwz     r9,28(r4)
+       addi    r4,r4,0x20
+       cmplw   cr5,r8,r10
+       cmplw   cr1,r9,r6
+       bne     cr5,L(st2)
+       bne     cr1,L(st1)
+       bdnz    L(word8_compare_loop)
+
+L(preword2_count_loop):
+       srwi.   r6,r5,3
+       beq     L(prebyte_count_loop)
+       mtctr   r6
+       clrlwi  r5,r5,29
+
+L(word2_count_loop):
+       lwz     r10,0(r3)
+       lwz     r6,4(r3)
+       addi    r3,r3,0x08
+       lwz     r8,0(r4)
+       lwz     r9,4(r4)
+       addi    r4,r4,0x08
+       cmplw   cr5,r8,r10
+       cmplw   cr1,r9,r6
+       bne     cr5,L(st2)
+       bne     cr1,L(st1)
+       bdnz    L(word2_count_loop)
+
+L(prebyte_count_loop):
+       addi    r5,r5,1
+       mtctr   r5
+       bdz     L(end_memcmp)
+
+L(byte_count_loop):
+       lbz     r6,0(r3)
+       addi    r3,r3,0x01
+       lbz     r8,0(r4)
+       addi    r4,r4,0x01
+       cmplw   cr5,r8,r6
+       bne     cr5,L(st2)
+       bdnz    L(byte_count_loop)
+
+L(end_memcmp):
+       addi    r3,r0,0
+       blr
+
+L(l_r):
+       addi    r3,r0,1
+       blr
+
+L(st1):
+       blt     cr1,L(l_r)
+       addi    r3,r0,-1
+       blr
+
+L(st2):
+       blt     cr5,L(l_r)
+       addi    r3,r0,-1
+       blr
+END (BP_SYM (memcmp))
+libc_hidden_builtin_def (memcmp)
+weak_alias (memcmp,bcmp)