diff options
Diffstat (limited to 'sysdeps/powerpc/powerpc64/power6/memset.S')
-rw-r--r-- | sysdeps/powerpc/powerpc64/power6/memset.S | 419 |
1 files changed, 419 insertions, 0 deletions
diff --git a/sysdeps/powerpc/powerpc64/power6/memset.S b/sysdeps/powerpc/powerpc64/power6/memset.S new file mode 100644 index 0000000000..ea74c117dd --- /dev/null +++ b/sysdeps/powerpc/powerpc64/power6/memset.S @@ -0,0 +1,419 @@ +/* Optimized 64-bit memset implementation for POWER6. + Copyright (C) 1997, 1999, 2000, 2002, 2003, 2007 + 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., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 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 (256 bits). There is a special case for setting cache lines + to 0, to take advantage of the dcbz instruction. */ + + .machine power6 +EALIGN (BP_SYM (memset), 7, 0) + CALL_MCOUNT 3 + +#define rTMP r0 +#define rRTN r3 /* Initial value of 1st argument. */ +#if __BOUNDED_POINTERS__ +# define rMEMP0 r4 /* Original value of 1st arg. */ +# define rCHR r5 /* Char to set in each byte. */ +# define rLEN r6 /* Length of region to set. */ +# define rMEMP r10 /* Address at which we are storing. */ +#else +# 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. */ +#endif +#define rALIGN r7 /* Number of bytes we are setting now (when aligning). */ +#define rMEMP2 r8 +#define rMEMP3 r9 /* Alt mem pointer. */ +L(_memset): +#if __BOUNDED_POINTERS__ + cmpldi cr1, rRTN, 0 + CHECK_BOUNDS_BOTH_WIDE (rMEMP0, rTMP, rTMP2, rLEN) + beq cr1, L(b0) + STORE_RETURN_VALUE (rMEMP0) + STORE_RETURN_BOUNDS (rTMP, rTMP2) +L(b0): +#endif +/* Take care of case for size <= 4. */ + cmpldi cr1, rLEN, 8 + andi. rALIGN, rMEMP0, 7 + mr rMEMP, rMEMP0 + ble cr1, L(small) + +/* Align to doubleword boundary. */ + cmpldi cr5, rLEN, 31 + rlwimi rCHR, rCHR, 8, 16, 23 /* Replicate byte to halfword. */ + beq+ L(aligned2) + mtcrf 0x01, rMEMP0 + subfic rALIGN, rALIGN, 8 + cror 28,30,31 /* Detect odd word aligned. */ + add rMEMP, rMEMP, rALIGN + sub rLEN, rLEN, rALIGN + rlwimi rCHR, rCHR, 16, 0, 15 /* Replicate halfword to word. */ + bt 29, L(g4) +/* Process the even word of doubleword. */ + bf+ 31, L(g2) + stb rCHR, 0(rMEMP0) + bt 30, L(g4x) +L(g2): + sth rCHR, -6(rMEMP) +L(g4x): + stw rCHR, -4(rMEMP) + b L(aligned) +/* Process the odd word of doubleword. */ +L(g4): + bf 28, L(g4x) /* If false, word aligned on odd word. */ + bf+ 31, L(g0) + stb rCHR, 0(rMEMP0) + bt 30, L(aligned) +L(g0): + sth rCHR, -2(rMEMP) + +/* Handle the case of size < 31. */ +L(aligned2): + rlwimi rCHR, rCHR, 16, 0, 15 /* Replicate halfword to word. */ +L(aligned): + mtcrf 0x01, rLEN + ble cr5, L(medium) +/* Align to 32-byte boundary. */ + andi. rALIGN, rMEMP, 0x18 + subfic rALIGN, rALIGN, 0x20 + insrdi rCHR,rCHR,32,0 /* Replicate word to double word. */ + 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) + stdu rCHR, -8(rMEMP2) +L(a1): blt cr1, L(a2) + std rCHR, -8(rMEMP2) + stdu rCHR, -16(rMEMP2) +L(a2): + +/* Now aligned to a 32 byte boundary. */ + .align 4 +L(caligned): + cmpldi cr1, rCHR, 0 + clrrdi. rALIGN, rLEN, 5 + mtcrf 0x01, rLEN + beq cr1, L(zloopstart) /* Special case for clearing memory using dcbz. */ + beq L(medium) /* We may not actually get to do a full line. */ + .align 4 +/* Storing a non-zero "c" value. We are aligned at a sector (32-byte) + boundary may not be at cache line (128-byte) boundary. */ +L(nzloopstart): +/* memset in 32-byte chunks until we get to a cache line boundary. + If rLEN is less then the distance to the next cache-line boundary use + cacheAligned1 code to finish the tail. */ + cmpldi cr1,rLEN,128 + + andi. rTMP,rMEMP,127 + blt cr1,L(cacheAligned1) + addi rMEMP3,rMEMP,32 + beq L(nzCacheAligned) + addi rLEN,rLEN,-32 + std rCHR,0(rMEMP) + std rCHR,8(rMEMP) + std rCHR,16(rMEMP) + addi rMEMP,rMEMP,32 + andi. rTMP,rMEMP3,127 + std rCHR,-8(rMEMP3) + + beq L(nzCacheAligned) + addi rLEN,rLEN,-32 + std rCHR,0(rMEMP3) + addi rMEMP,rMEMP,32 + std rCHR,8(rMEMP3) + andi. rTMP,rMEMP,127 + std rCHR,16(rMEMP3) + std rCHR,24(rMEMP3) + + beq L(nzCacheAligned) + addi rLEN,rLEN,-32 + std rCHR,32(rMEMP3) + addi rMEMP,rMEMP,32 + cmpldi cr1,rLEN,128 + std rCHR,40(rMEMP3) + cmpldi cr6,rLEN,256 + li rMEMP2,128 + std rCHR,48(rMEMP3) + std rCHR,56(rMEMP3) + blt cr1,L(cacheAligned1) + b L(nzCacheAligned128) + +/* Now we are aligned to the cache line and can use dcbtst. */ + .align 4 +L(nzCacheAligned): + cmpldi cr1,rLEN,128 + blt cr1,L(cacheAligned1) + b L(nzCacheAligned128) + .align 5 +L(nzCacheAligned128): + cmpldi cr1,rLEN,256 + addi rMEMP3,rMEMP,64 + std rCHR,0(rMEMP) + std rCHR,8(rMEMP) + std rCHR,16(rMEMP) + std rCHR,24(rMEMP) + std rCHR,32(rMEMP) + std rCHR,40(rMEMP) + std rCHR,48(rMEMP) + std rCHR,56(rMEMP) + addi rMEMP,rMEMP3,64 + addi rLEN,rLEN,-128 + std rCHR,0(rMEMP3) + std rCHR,8(rMEMP3) + std rCHR,16(rMEMP3) + std rCHR,24(rMEMP3) + std rCHR,32(rMEMP3) + std rCHR,40(rMEMP3) + std rCHR,48(rMEMP3) + std rCHR,56(rMEMP3) + bge cr1,L(nzCacheAligned128) + dcbtst 0,rMEMP + b L(cacheAligned1) + .align 5 +/* Storing a zero "c" value. We are aligned at a sector (32-byte) + boundary but may not be at cache line (128-byte) boundary. If the + remaining length spans a full cache line we can use the Data cache + block zero instruction. */ +L(zloopstart): +/* memset in 32-byte chunks until we get to a cache line boundary. + If rLEN is less then the distance to the next cache-line boundary use + cacheAligned1 code to finish the tail. */ + cmpldi cr1,rLEN,128 + beq L(medium) +L(getCacheAligned): + andi. rTMP,rMEMP,127 + nop + blt cr1,L(cacheAligned1) + addi rMEMP3,rMEMP,32 + beq L(cacheAligned) + addi rLEN,rLEN,-32 + std rCHR,0(rMEMP) + std rCHR,8(rMEMP) + std rCHR,16(rMEMP) + addi rMEMP,rMEMP,32 + andi. rTMP,rMEMP3,127 + std rCHR,-8(rMEMP3) +L(getCacheAligned2): + beq L(cacheAligned) + addi rLEN,rLEN,-32 + std rCHR,0(rMEMP3) + std rCHR,8(rMEMP3) + addi rMEMP,rMEMP,32 + andi. rTMP,rMEMP,127 + std rCHR,16(rMEMP3) + std rCHR,24(rMEMP3) +L(getCacheAligned3): + beq L(cacheAligned) + addi rLEN,rLEN,-32 + std rCHR,32(rMEMP3) + addi rMEMP,rMEMP,32 + cmpldi cr1,rLEN,128 + std rCHR,40(rMEMP3) + cmpldi cr6,rLEN,256 + li rMEMP2,128 + std rCHR,48(rMEMP3) + std rCHR,56(rMEMP3) + blt cr1,L(cacheAligned1) + blt cr6,L(cacheAligned128) + b L(cacheAlignedx) + +/* Now we are aligned to the cache line and can use dcbz. */ + .align 5 +L(cacheAligned): + cmpldi cr1,rLEN,128 + cmpldi cr6,rLEN,256 + blt cr1,L(cacheAligned1) + li rMEMP2,128 +L(cacheAlignedx): + cmpldi cr5,rLEN,640 + blt cr6,L(cacheAligned128) + bgt cr5,L(cacheAligned512) + cmpldi cr6,rLEN,512 + dcbz 0,rMEMP + cmpldi cr1,rLEN,384 + dcbz rMEMP2,rMEMP + addi rMEMP,rMEMP,256 + addi rLEN,rLEN,-256 + blt cr1,L(cacheAligned1) + blt cr6,L(cacheAligned128) + b L(cacheAligned256) + .align 5 +/* A simple loop for the longer (>640 bytes) lengths. This form limits + the branch miss-predicted to exactly 1 at loop exit.*/ +L(cacheAligned512): + cmpli cr1,rLEN,128 + blt cr1,L(cacheAligned1) + dcbz 0,rMEMP + addi rLEN,rLEN,-128 + addi rMEMP,rMEMP,128 + b L(cacheAligned512) + .align 5 +L(cacheAligned256): + + cmpldi cr6,rLEN,512 + + dcbz 0,rMEMP + cmpldi cr1,rLEN,384 + dcbz rMEMP2,rMEMP + addi rMEMP,rMEMP,256 + addi rLEN,rLEN,-256 + + bge cr6,L(cacheAligned256) + + blt cr1,L(cacheAligned1) + .align 4 +L(cacheAligned128): + dcbz 0,rMEMP + addi rMEMP,rMEMP,128 + addi rLEN,rLEN,-128 + nop +L(cacheAligned1): + cmpldi cr1,rLEN,32 + blt cr1,L(handletail32) + addi rMEMP3,rMEMP,32 + addi rLEN,rLEN,-32 + std rCHR,0(rMEMP) + std rCHR,8(rMEMP) + std rCHR,16(rMEMP) + addi rMEMP,rMEMP,32 + cmpldi cr1,rLEN,32 + std rCHR,-8(rMEMP3) +L(cacheAligned2): + blt cr1,L(handletail32) + addi rLEN,rLEN,-32 + std rCHR,0(rMEMP3) + std rCHR,8(rMEMP3) + addi rMEMP,rMEMP,32 + cmpldi cr1,rLEN,32 + std rCHR,16(rMEMP3) + std rCHR,24(rMEMP3) + nop +L(cacheAligned3): + blt cr1,L(handletail32) + addi rMEMP,rMEMP,32 + addi rLEN,rLEN,-32 + std rCHR,32(rMEMP3) + std rCHR,40(rMEMP3) + std rCHR,48(rMEMP3) + std rCHR,56(rMEMP3) + +/* We are here because the length or remainder (rLEN) is less than the + cache line/sector size and does not justify aggressive loop unrolling. + So set up the preconditions for L(medium) and go there. */ + .align 3 +L(handletail32): + cmpldi cr1,rLEN,0 + beqlr cr1 + b L(medium) + + .align 5 +L(small): +/* Memset of 8 bytes or less. */ + cmpldi cr6, rLEN, 4 + cmpldi cr5, rLEN, 1 + ble cr6,L(le4) + subi rLEN, rLEN, 4 + stb rCHR,0(rMEMP) + stb rCHR,1(rMEMP) + stb rCHR,2(rMEMP) + stb rCHR,3(rMEMP) + addi rMEMP,rMEMP, 4 + cmpldi cr5, rLEN, 1 +L(le4): + cmpldi 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): + insrdi rCHR,rCHR,32,0 /* Replicate word to double word. */ + cmpldi 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 + std 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): + std rCHR, -8(rMEMP) + stdu rCHR, -16(rMEMP) +L(medium_27f): + bflr 28 +L(medium_28t): + std rCHR, -8(rMEMP) + blr +END_GEN_TB (BP_SYM (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 (BP_SYM (__bzero)) + CALL_MCOUNT 3 +#if __BOUNDED_POINTERS__ + mr r6,r4 + li r5,0 + mr r4,r3 + /* Tell memset that we don't want a return value. */ + li r3,0 + b L(_memset) +#else + mr r5,r4 + li r4,0 + b L(_memset) +#endif +END_GEN_TB (BP_SYM (__bzero),TB_TOCLESS) + +weak_alias (BP_SYM (__bzero), BP_SYM (bzero)) |