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Diffstat (limited to 'sysdeps/powerpc/powerpc64/memset.S')
| -rw-r--r-- | sysdeps/powerpc/powerpc64/memset.S | 296 |
1 files changed, 296 insertions, 0 deletions
diff --git a/sysdeps/powerpc/powerpc64/memset.S b/sysdeps/powerpc/powerpc64/memset.S new file mode 100644 index 0000000000..4bfe20d7b1 --- /dev/null +++ b/sysdeps/powerpc/powerpc64/memset.S @@ -0,0 +1,296 @@ +/* Optimized memset implementation for PowerPC64. + Copyright (C) 1997, 1999, 2000, 2002 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> + +/* Define a global static that can hold the cache line size. The + assumption is that startup code will access the "aux vector" to + to obtain the value set by the kernel and store it into this + variable. */ + .globl __cache_line_size + .section ".data" + .align 2 + .type __cache_line_size,@object + .size __cache_line_size,4 +__cache_line_size: + .long 0 + .section ".toc","aw" +.LC0: + .tc __cache_line_size[TC],__cache_line_size + .section ".text" + .align 2 + +/* __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. */ + +EALIGN (BP_SYM (memset), 5, 0) + +#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 rNEG64 r8 /* Constant -64 for clearing with dcbz. */ +#define rCLS r8 /* Cache line size obtained from static. */ +#define rCLM r9 /* Cache line size mask to check for cache alignment. */ + +___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. */ +L(caligned): + cmpldi cr1, rCHR, 0 + clrrdi. rALIGN, rLEN, 5 + mtcrf 0x01, rLEN + beq cr1, L(zloopstart) /* Special case for clearing memory using dcbz. */ +L(nondcbz): + srdi rTMP, rALIGN, 5 + mtctr rTMP + beq L(medium) /* We may not actually get to do a full line. */ + clrldi. rLEN, rLEN, 59 + add rMEMP, rMEMP, rALIGN + li rNEG64, -0x40 + bdz L(cloopdone) + +L(c3): dcbtst rNEG64, rMEMP + std rCHR, -8(rMEMP) + std rCHR, -16(rMEMP) + std rCHR, -24(rMEMP) + stdu rCHR, -32(rMEMP) + bdnz L(c3) +L(cloopdone): + std rCHR, -8(rMEMP) + std rCHR, -16(rMEMP) + cmpldi cr1, rLEN, 16 + std rCHR, -24(rMEMP) + stdu 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) + ld rCLS,.LC0@toc(r2) + lwz rCLS,0(rCLS) +/* If the cache line size was not set just goto to L(nondcbz) which is + safe for any cache line size. */ + cmpldi cr1,rCLS,0 + beq cr1,L(nondcbz) + + +/* Now we know the cache line size, and it is not 32-bytes, but + we may not yet be aligned to the cache line. May have a partial + line to fill, so touch it 1st. */ + dcbt 0,rMEMP + addi rCLM,rCLS,-1 +L(getCacheAligned): + cmpldi cr1,rLEN,32 + and. rTMP,rCLM,rMEMP + blt cr1,L(handletail32) + beq L(cacheAligned) + addi rMEMP,rMEMP,32 + addi rLEN,rLEN,-32 + std rCHR,-32(rMEMP) + std rCHR,-24(rMEMP) + std rCHR,-16(rMEMP) + std rCHR,-8(rMEMP) + b L(getCacheAligned) + +/* Now we are aligned to the cache line and can use dcbz. */ +L(cacheAligned): + cmpld 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 was not 32-bytes + and the remainder (rLEN) is less than the actual cache line size. + So set up the preconditions for L(nondcbz) and go there. */ +L(handletail32): + clrrwi. rALIGN, rLEN, 5 + b L(nondcbz) + + .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) + +/* Copied from bzero.S to prevent the linker from inserting a stub + between bzero and memset. */ +ENTRY (BP_SYM (__bzero)) +#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 ___memset +#else + mr r5,r4 + li r4,0 + b ___memset +#endif +END_GEN_TB (BP_SYM (__bzero),TB_TOCLESS) + +weak_alias (BP_SYM (__bzero), BP_SYM (bzero)) + |