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-rw-r--r--sysdeps/powerpc/powerpc32/power6/memset.S231
1 files changed, 231 insertions, 0 deletions
diff --git a/sysdeps/powerpc/powerpc32/power6/memset.S b/sysdeps/powerpc/powerpc32/power6/memset.S
new file mode 100644
index 0000000000..71c1209fa4
--- /dev/null
+++ b/sysdeps/powerpc/powerpc32/power6/memset.S
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+/* Optimized memset implementation for PowerPC64.
+   Copyright (C) 1997,99, 2000,02,03, 2006 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, write to the Free
+   Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA
+   02110-1301 USA.  */
+
+#include <sysdep.h>
+#include <bp-sym.h>
+#include <bp-asm.h>
+
+/* __ptr_t [r3] memset (__ptr_t s [r3], int c [r4], size_t n [r5]));
+   Returns 's'.
+
+   The memset is done in three sizes: byte (8 bits), word (32 bits),
+   cache line (1024 bits). There is a special case for setting cache lines
+   to 0, to take advantage of the dcbz instruction.  */
+
+EALIGN (BP_SYM (memset), 5, 0)
+	CALL_MCOUNT
+
+#define rTMP	r0
+#define rRTN	r3	/* Initial value of 1st argument.  */
+#define rMEMP0	r3	/* Original value of 1st arg.  */
+#define rCHR	r4	/* Char to set in each byte.  */
+#define rLEN	r5	/* Length of region to set.  */
+#define rMEMP	r6	/* Address at which we are storing.  */
+#define rALIGN	r7	/* Number of bytes we are setting now (when aligning). */
+#define rMEMP2	r8
+
+#define rNEG64	r8	/* Constant -64 for clearing with dcbz.  */
+#define rCLS	r8	/* Cache line size (known to be 128).  */
+#define rCLM	r9	/* Cache line size mask to check for cache alignment.  */
+L(_memset):
+/* Take care of case for size <= 4.  */
+	cmplwi	cr1, rLEN, 4
+	andi.	rALIGN, rMEMP0, 3
+	mr	rMEMP, rMEMP0
+	ble-	cr1, L(small)
+
+/* Align to word boundary.  */
+	cmplwi	cr5, rLEN, 31
+	rlwimi	rCHR, rCHR, 8, 16, 23 /* Replicate byte to halfword.  */
+	beq+	L(aligned)
+	mtcrf	0x01, rMEMP0
+	subfic	rALIGN, rALIGN, 4
+	add	rMEMP, rMEMP, rALIGN
+	sub	rLEN, rLEN, rALIGN
+	bf+	31, L(g0)
+	stb	rCHR, 0(rMEMP0)
+	bt	30, L(aligned)
+L(g0):
+	sth	rCHR, -2(rMEMP)
+
+        .align 4
+/* Handle the case of size < 31.  */
+L(aligned):
+	mtcrf	0x01, rLEN
+	rlwimi	rCHR, rCHR, 16, 0, 15 /* Replicate halfword to word.  */
+	ble	cr5, L(medium)
+/* Align to 32-byte boundary.  */
+	andi.	rALIGN, rMEMP, 0x1C
+	subfic	rALIGN, rALIGN, 0x20
+	beq	L(caligned)
+	mtcrf	0x01, rALIGN
+	add	rMEMP, rMEMP, rALIGN
+	sub	rLEN, rLEN, rALIGN
+	cmplwi	cr1, rALIGN, 0x10
+	mr	rMEMP2, rMEMP
+	bf	28, L(a1)
+        stw     rCHR, -4(rMEMP2)
+	stwu	rCHR, -8(rMEMP2)
+L(a1):	blt	cr1, L(a2)
+        stw     rCHR, -4(rMEMP2)
+	stw	rCHR, -8(rMEMP2)
+	stw	rCHR, -12(rMEMP2)
+	stwu	rCHR, -16(rMEMP2)
+L(a2):  bf      29, L(caligned)
+        stw     rCHR, -4(rMEMP2)
+
+        .align 4
+/* Now aligned to a 32 byte boundary.  */
+L(caligned):
+	cmplwi	cr1, rCHR, 0
+	clrrwi.	rALIGN, rLEN, 5
+	mtcrf	0x01, rLEN
+	beq	cr1, L(zloopstart) /* Special case for clearing memory using dcbz.  */
+L(nondcbz):
+	srwi	rTMP, rALIGN, 5
+	mtctr	rTMP
+	beq	L(medium)	/* We may not actually get to do a full line.  */
+	clrlwi.	rLEN, rLEN, 27
+	add	rMEMP, rMEMP, rALIGN
+	li	rNEG64, -0x40
+	bdz	L(cloopdone)
+
+        .align 4
+L(c3): 	dcbtst	rNEG64, rMEMP
+        stw     rCHR, -4(rMEMP)
+	stw	rCHR, -8(rMEMP)
+        stw     rCHR, -12(rMEMP)
+	stw	rCHR, -16(rMEMP)
+        stw     rCHR, -20(rMEMP)
+	stw	rCHR, -24(rMEMP)
+        stw     rCHR, -28(rMEMP)
+	stwu	rCHR, -32(rMEMP)
+	bdnz	L(c3)
+L(cloopdone):
+        stw     rCHR, -4(rMEMP)
+	stw	rCHR, -8(rMEMP)
+        stw     rCHR, -12(rMEMP)
+	stw	rCHR, -16(rMEMP)
+	cmplwi	cr1, rLEN, 16
+        stw     rCHR, -20(rMEMP)
+	stw	rCHR, -24(rMEMP)
+        stw     rCHR, -28(rMEMP)
+	stwu	rCHR, -32(rMEMP)
+	beqlr
+	add	rMEMP, rMEMP, rALIGN
+	b	L(medium_tail2)
+
+	.align 5
+/* Clear lines of memory in 128-byte chunks.  */
+L(zloopstart):
+/* If the remaining length is less the 32 bytes, don't bother getting
+	 the cache line size.  */
+	beq	L(medium)
+	li      rCLS,128  /* cache line size is 128 */
+	dcbt	0,rMEMP
+L(getCacheAligned):
+	cmplwi	cr1,rLEN,32
+	andi.	rTMP,rMEMP,127
+	blt	cr1,L(handletail32)
+	beq	L(cacheAligned)
+	addi	rMEMP,rMEMP,32
+	addi	rLEN,rLEN,-32
+	stw	rCHR,-32(rMEMP)
+        stw     rCHR,-28(rMEMP)
+	stw	rCHR,-24(rMEMP)
+	stw     rCHR,-20(rMEMP)
+	stw	rCHR,-16(rMEMP)
+        stw     rCHR,-12(rMEMP)
+	stw	rCHR,-8(rMEMP)
+        stw     rCHR,-4(rMEMP)
+	b	L(getCacheAligned)
+
+/* Now we are aligned to the cache line and can use dcbz.  */
+        .align 4
+L(cacheAligned):
+	cmplw	cr1,rLEN,rCLS
+	blt	cr1,L(handletail32)
+	dcbz	0,rMEMP
+	subf	rLEN,rCLS,rLEN
+	add	rMEMP,rMEMP,rCLS
+	b	L(cacheAligned)
+
+/* We are here because the cache line size was set and the remainder 
+  (rLEN) is less than the actual cache line size.
+   So set up the preconditions for L(nondcbz) and go there.  */
+        .align 3
+L(handletail32):
+	clrrwi.	rALIGN, rLEN, 5
+	b		L(nondcbz)
+
+	.align 5
+L(small):
+/* Memset of 4 bytes or less.  */
+	cmplwi	cr5, rLEN, 1
+	cmplwi	cr1, rLEN, 3
+	bltlr	cr5
+	stb	rCHR, 0(rMEMP)
+	beqlr	cr5
+	stb	rCHR, 1(rMEMP)
+	bltlr	cr1
+	stb	rCHR, 2(rMEMP)
+	beqlr	cr1
+	stb	rCHR, 3(rMEMP)
+	blr
+
+/* Memset of 0-31 bytes.  */
+	.align 5
+L(medium):
+	cmplwi	cr1, rLEN, 16
+L(medium_tail2):
+	add	rMEMP, rMEMP, rLEN
+L(medium_tail):
+	bt-	31, L(medium_31t)
+	bt-	30, L(medium_30t)
+L(medium_30f):
+	bt-	29, L(medium_29t)
+L(medium_29f):
+	bge-	cr1, L(medium_27t)
+	bflr-	28
+        stw     rCHR, -4(rMEMP)
+	stw	rCHR, -8(rMEMP)
+	blr
+
+L(medium_31t):
+	stbu	rCHR, -1(rMEMP)
+	bf-	30, L(medium_30f)
+L(medium_30t):
+	sthu	rCHR, -2(rMEMP)
+	bf-	29, L(medium_29f)
+L(medium_29t):
+	stwu	rCHR, -4(rMEMP)
+	blt-	cr1, L(medium_27f)
+L(medium_27t):
+        stw     rCHR, -4(rMEMP)
+	stw	rCHR, -8(rMEMP)
+        stw     rCHR, -12(rMEMP)
+	stwu	rCHR, -16(rMEMP)
+L(medium_27f):
+	bflr-	28
+L(medium_28t):
+        stw     rCHR, -4(rMEMP)
+	stw	rCHR, -8(rMEMP)
+	blr
+END (BP_SYM (memset))
+libc_hidden_builtin_def (memset)