diff options
Diffstat (limited to 'sysdeps/powerpc/powerpc32/power6/memset.S')
| -rw-r--r-- | sysdeps/powerpc/powerpc32/power6/memset.S | 231 |
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 @@ -0,0 +1,231 @@ +/* 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) |