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-rw-r--r--REORG.TODO/sysdeps/powerpc/powerpc64/power8/memset.S458
1 files changed, 458 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/powerpc/powerpc64/power8/memset.S b/REORG.TODO/sysdeps/powerpc/powerpc64/power8/memset.S
new file mode 100644
index 0000000000..bc734c9f4f
--- /dev/null
+++ b/REORG.TODO/sysdeps/powerpc/powerpc64/power8/memset.S
@@ -0,0 +1,458 @@
+/* Optimized memset implementation for PowerPC64/POWER8.
+   Copyright (C) 2014-2017 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>
+
+#define MTVSRD_V1_R4  .long 0x7c240166     /* mtvsrd  v1,r4  */
+
+/* __ptr_t [r3] memset (__ptr_t s [r3], int c [r4], size_t n [r5]));
+   Returns 's'.  */
+
+#ifndef MEMSET
+# define MEMSET memset
+#endif
+
+	/* No need to use .machine power8 since mtvsrd is already
+	   handled by the define.  It avoid breakage on binutils
+	   that does not support this machine specifier.  */
+	.machine power7
+EALIGN (MEMSET, 5, 0)
+	CALL_MCOUNT 3
+
+L(_memset):
+	cmpldi	cr7,r5,31
+	neg	r0,r3
+	mr	r10,r3
+
+	insrdi	r4,r4,8,48
+	insrdi	r4,r4,16,32	/* Replicate byte to word.  */
+	ble	cr7,L(write_LT_32)
+
+	andi.	r11,r10,15	/* Check alignment of DST.  */
+	insrdi	r4,r4,32,0	/* Replicate word to double word.  */
+
+	beq	L(big_aligned)
+
+	mtocrf	0x01,r0
+	clrldi	r0,r0,60
+
+	/* Get DST aligned to 16 bytes.  */
+1:	bf	31,2f
+	stb	r4,0(r10)
+	addi	r10,r10,1
+
+2:	bf	30,4f
+	sth	r4,0(r10)
+	addi	r10,r10,2
+
+4:	bf	29,8f
+	stw	r4,0(r10)
+	addi	r10,r10,4
+
+8:	bf      28,16f
+	std     r4,0(r10)
+	addi    r10,r10,8
+
+16:	subf	r5,r0,r5
+
+	.align	4
+L(big_aligned):
+	/* For sizes larger than 255 two possible paths:
+	   - if constant is '0', zero full cache lines with dcbz
+	   - otherwise uses vector instructions.  */
+	cmpldi	cr5,r5,255
+	dcbtst	0,r10
+	cmpldi	cr6,r4,0
+	crand	27,26,21
+	bt	27,L(huge_dcbz)
+	bge	cr5,L(huge_vector)
+
+
+	/* Size between 32 and 255 bytes with constant different than 0, use
+	   doubleword store instruction to achieve best throughput.  */
+	srdi    r8,r5,5
+	clrldi  r11,r5,59
+	cmpldi  cr6,r11,0
+	cmpdi	r8,0
+	beq     L(tail_bytes)
+	mtctr   r8
+
+	/* Main aligned write loop, writes 32-bytes at a time.  */
+	.align  4
+L(big_loop):
+	std     r4,0(r10)
+	std     r4,8(r10)
+	std     r4,16(r10)
+	std     r4,24(r10)
+	addi    r10,r10,32
+	bdz     L(tail_bytes)
+
+	std     r4,0(r10)
+	std     r4,8(r10)
+	std     r4,16(r10)
+	std     r4,24(r10)
+	addi    r10,10,32
+	bdnz    L(big_loop)
+
+	b       L(tail_bytes)
+
+	/* Write remaining 1~31 bytes.  */
+	.align  4
+L(tail_bytes):
+	beqlr   cr6
+
+	srdi    r7,r11,4
+	clrldi  r8,r11,60
+	mtocrf  0x01,r7
+
+	.align	4
+	bf	31,8f
+	std	r4,0(r10)
+	std	r4,8(r10)
+	addi	r10,r10,16
+
+	.align	4
+8:	mtocrf	0x1,r8
+	bf	28,4f
+	std	r4,0(r10)
+	addi	r10,r10,8
+
+	.align	4
+4:	bf      29,2f
+	stw     4,0(10)
+	addi    10,10,4
+
+	.align 	4
+2:	bf      30,1f
+	sth     4,0(10)
+	addi    10,10,2
+
+	.align  4
+1:      bflr    31
+	stb     4,0(10)
+	blr
+
+	/* Size larger than 255 bytes with constant different than 0, use
+	   vector instruction to achieve best throughput.  */
+L(huge_vector):
+	/* Replicate set byte to quadword in VMX register.  */
+	MTVSRD_V1_R4
+	xxpermdi 32,v0,v1,0
+	vspltb	 v2,v0,15
+
+	/* Main aligned write loop: 128 bytes at a time.  */
+	li	r6,16
+	li	r7,32
+	li	r8,48
+	mtocrf	0x02,r5
+	srdi	r12,r5,7
+	cmpdi	r12,0
+	beq	L(aligned_tail)
+	mtctr	r12
+	b	L(aligned_128loop)
+
+	.align  4
+L(aligned_128loop):
+	stvx	v2,0,r10
+	stvx	v2,r10,r6
+	stvx	v2,r10,r7
+	stvx	v2,r10,r8
+	addi	r10,r10,64
+	stvx	v2,0,r10
+	stvx	v2,r10,r6
+	stvx	v2,r10,r7
+	stvx	v2,r10,r8
+	addi	r10,r10,64
+	bdnz	L(aligned_128loop)
+
+	/* Write remaining 1~127 bytes.  */
+L(aligned_tail):
+	mtocrf	0x01,r5
+	bf	25,32f
+	stvx	v2,0,r10
+	stvx	v2,r10,r6
+	stvx	v2,r10,r7
+	stvx	v2,r10,r8
+	addi	r10,r10,64
+
+32:	bf	26,16f
+	stvx	v2,0,r10
+	stvx	v2,r10,r6
+	addi	r10,r10,32
+
+16:	bf	27,8f
+	stvx	v2,0,r10
+	addi	r10,r10,16
+
+8:	bf	28,4f
+	std     r4,0(r10)
+	addi	r10,r10,8
+
+	/* Copies 4~7 bytes.  */
+4:	bf	29,L(tail2)
+	stw     r4,0(r10)
+	bf      30,L(tail5)
+	sth     r4,4(r10)
+	bflr	31
+	stb     r4,6(r10)
+	/* Return original DST pointer.  */
+	blr
+
+	/* Special case when value is 0 and we have a long length to deal
+	   with.  Use dcbz to zero out a full cacheline of 128 bytes at a time.
+	   Before using dcbz though, we need to get the destination 128-byte
+	   aligned.  */
+	.align	4
+L(huge_dcbz):
+	andi.	r11,r10,127
+	neg	r0,r10
+	beq	L(huge_dcbz_aligned)
+
+	clrldi	r0,r0,57
+	subf	r5,r0,r5
+	srdi	r0,r0,3
+	mtocrf	0x01,r0
+
+	/* Write 1~128 bytes until DST is aligned to 128 bytes.  */
+8:	bf	28,4f
+
+	std	r4,0(r10)
+	std	r4,8(r10)
+	std	r4,16(r10)
+	std	r4,24(r10)
+	std	r4,32(r10)
+	std	r4,40(r10)
+	std	r4,48(r10)
+	std	r4,56(r10)
+	addi	r10,r10,64
+
+	.align	4
+4:	bf	29,2f
+	std	r4,0(r10)
+	std	r4,8(r10)
+	std	r4,16(r10)
+	std	r4,24(r10)
+	addi	r10,r10,32
+
+	.align	4
+2:	bf	30,1f
+	std	r4,0(r10)
+	std	r4,8(r10)
+	addi	r10,r10,16
+
+	.align	4
+1:	bf	31,L(huge_dcbz_aligned)
+	std	r4,0(r10)
+	addi	r10,r10,8
+
+L(huge_dcbz_aligned):
+	/* Setup dcbz unroll offsets and count numbers.  */
+	srdi	r8,r5,9
+	clrldi	r11,r5,55
+	cmpldi	cr6,r11,0
+	li	r9,128
+	cmpdi	r8,0
+	beq     L(huge_tail)
+	li	r7,256
+	li	r6,384
+	mtctr	r8
+
+	.align	4
+L(huge_loop):
+	/* Sets 512 bytes to zero in each iteration, the loop unrolling shows
+	   a throughput boost for large sizes (2048 bytes or higher).  */
+	dcbz	0,r10
+	dcbz	r9,r10
+	dcbz	r7,r10
+	dcbz	r6,r10
+	addi	r10,r10,512
+	bdnz	L(huge_loop)
+
+	beqlr	cr6
+
+L(huge_tail):
+	srdi    r6,r11,8
+	srdi    r7,r11,4
+	clrldi  r8,r11,4
+	cmpldi  cr6,r8,0
+	mtocrf  0x01,r6
+
+	beq	cr6,L(tail)
+
+	/* We have 1~511 bytes remaining.  */
+	.align	4
+32:	bf	31,16f
+	dcbz	0,r10
+	dcbz	r9,r10
+	addi	r10,r10,256
+
+	.align	4
+16:	mtocrf  0x01,r7
+	bf	28,8f
+	dcbz	0,r10
+	addi	r10,r10,128
+
+	.align 	4
+8:	bf	29,4f
+	std	r4,0(r10)
+	std	r4,8(r10)
+	std	r4,16(r10)
+	std	r4,24(r10)
+	std	r4,32(r10)
+	std	r4,40(r10)
+	std	r4,48(r10)
+	std	r4,56(r10)
+	addi	r10,r10,64
+
+	.align	4
+4:	bf	30,2f
+	std	r4,0(r10)
+	std	r4,8(r10)
+	std	r4,16(r10)
+	std	r4,24(r10)
+	addi	r10,r10,32
+
+	.align	4
+2:	bf	31,L(tail)
+	std	r4,0(r10)
+	std	r4,8(r10)
+	addi	r10,r10,16
+	.align	4
+
+	/* Remaining 1~15 bytes.  */
+L(tail):
+	mtocrf  0x01,r8
+
+	.align
+8:	bf	28,4f
+	std	r4,0(r10)
+	addi	r10,r10,8
+
+	.align	4
+4:	bf	29,2f
+	stw	r4,0(r10)
+	addi	r10,r10,4
+
+	.align	4
+2:	bf	30,1f
+	sth	r4,0(r10)
+	addi	r10,r10,2
+
+	.align	4
+1:	bflr	31
+	stb	r4,0(r10)
+	blr
+
+	/* Handle short copies of 0~31 bytes.  Best throughput is achieved
+	   by just unrolling all operations.  */
+	.align	4
+L(write_LT_32):
+	cmpldi	cr6,5,8
+	mtocrf	0x01,r5
+	ble	cr6,L(write_LE_8)
+
+	/* At least 9 bytes to go.  */
+	neg	r8,r4
+	andi.	r0,r8,3
+	cmpldi	cr1,r5,16
+	beq	L(write_LT_32_aligned)
+
+	/* Force 4-byte alignment for SRC.  */
+	mtocrf	0x01,r0
+	subf	r5,r0,r5
+
+2:	bf	30,1f
+	sth	r4,0(r10)
+	addi	r10,r10,2
+
+1:	bf	31,L(end_4bytes_alignment)
+	stb	r4,0(r10)
+	addi	r10,r10,1
+
+	.align	4
+L(end_4bytes_alignment):
+	cmpldi	cr1,r5,16
+	mtocrf	0x01,r5
+
+L(write_LT_32_aligned):
+	blt	cr1,8f
+
+	stw	r4,0(r10)
+	stw	r4,4(r10)
+	stw	r4,8(r10)
+	stw	r4,12(r10)
+	addi	r10,r10,16
+
+8:	bf	28,L(tail4)
+	stw	r4,0(r10)
+	stw	r4,4(r10)
+	addi	r10,r10,8
+
+	.align	4
+	/* Copies 4~7 bytes.  */
+L(tail4):
+	bf	29,L(tail2)
+	stw	r4,0(r10)
+	bf	30,L(tail5)
+	sth	r4,4(r10)
+	bflr	31
+	stb	r4,6(r10)
+	blr
+
+	.align	4
+	/* Copies 2~3 bytes.  */
+L(tail2):
+	bf	30,1f
+	sth	r4,0(r10)
+	bflr	31
+	stb	r4,2(r10)
+	blr
+
+	.align	4
+L(tail5):
+	bflr	31
+	stb	r4,4(r10)
+	blr
+
+	.align	4
+1: 	bflr	31
+	stb	r4,0(r10)
+	blr
+
+	/* Handles copies of 0~8 bytes.  */
+	.align	4
+L(write_LE_8):
+	bne	cr6,L(tail4)
+
+	stw	r4,0(r10)
+	stw	r4,4(r10)
+	blr
+END_GEN_TB (MEMSET,TB_TOCLESS)
+libc_hidden_builtin_def (memset)
+
+/* Copied from bzero.S to prevent the linker from inserting a stub
+   between bzero and memset.  */
+ENTRY (__bzero)
+	CALL_MCOUNT 3
+	mr	r5,r4
+	li	r4,0
+	b	L(_memset)
+END (__bzero)
+#ifndef __bzero
+weak_alias (__bzero, bzero)
+#endif