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Diffstat (limited to 'ports/sysdeps/powerpc/powerpc32/405/memcmp.S')
-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)