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Diffstat (limited to 'sysdeps/powerpc/powerpc64/a2/memcpy.S')
| -rw-r--r-- | sysdeps/powerpc/powerpc64/a2/memcpy.S | 501 |
1 files changed, 501 insertions, 0 deletions
diff --git a/sysdeps/powerpc/powerpc64/a2/memcpy.S b/sysdeps/powerpc/powerpc64/a2/memcpy.S new file mode 100644 index 0000000000..ac95171aa8 --- /dev/null +++ b/sysdeps/powerpc/powerpc64/a2/memcpy.S @@ -0,0 +1,501 @@ +/* Optimized memcpy implementation for PowerPC A2. + Copyright (C) 2010 Free Software Foundation, Inc. + Contributed by Michael Brutman <brutman@us.ibm.com>. + 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 PREFETCH_AHEAD 4 /* no cache lines SRC prefetching ahead */ +#define ZERO_AHEAD 2 /* no cache lines DST zeroing ahead */ + + .section ".toc","aw" +.LC0: + .tc __cache_line_size[TC],__cache_line_size + .section ".text" + .align 2 + + + .machine a2 +EALIGN (BP_SYM (memcpy), 5, 0) + CALL_MCOUNT 3 + + dcbt 0,r4 /* Prefetch ONE SRC cacheline */ + cmpldi cr1,r5,16 /* is size < 16 ? */ + mr r6,r3 /* Copy dest reg to r6; */ + blt+ cr1,L(shortcopy) + + + /* Big copy (16 bytes or more) + + Figure out how far to the nearest quadword boundary, or if we are + on one already. Also get the cache line size. + + r3 - return value (always) + r4 - current source addr + r5 - copy length + r6 - current dest addr + */ + + neg r8,r3 /* LS 4 bits = # bytes to 8-byte dest bdry */ + ld r9,.LC0@toc(r2) /* Get cache line size (part 1) */ + clrldi r8,r8,64-4 /* align to 16byte boundary */ + sub r7,r4,r3 /* compute offset to src from dest */ + lwz r9,0(r9) /* Get cache line size (part 2) */ + cmpldi cr0,r8,0 /* Were we aligned on a 16 byte bdy? */ + addi r10,r9,-1 /* Cache line mask */ + beq+ L(dst_aligned) + + + + /* Destination is not aligned on quadword boundary. Get us to one. + + r3 - return value (always) + r4 - current source addr + r5 - copy length + r6 - current dest addr + r7 - offset to src from dest + r8 - number of bytes to quadword boundary + */ + + mtcrf 0x01,r8 /* put #bytes to boundary into cr7 */ + subf r5,r8,r5 /* adjust remaining len */ + + bf cr7*4+3,1f + lbzx r0,r7,r6 /* copy 1 byte addr */ + stb r0,0(r6) + addi r6,r6,1 +1: + bf cr7*4+2,2f + lhzx r0,r7,r6 /* copy 2 byte addr */ + sth r0,0(r6) + addi r6,r6,2 +2: + bf cr7*4+1,4f + lwzx r0,r7,r6 /* copy 4 byte addr */ + stw r0,0(r6) + addi r6,r6,4 +4: + bf cr7*4+0,8f + ldx r0,r7,r6 /* copy 8 byte addr */ + std r0,0(r6) + addi r6,r6,8 +8: + add r4,r7,r6 /* update src addr */ + + + + /* Dest is quadword aligned now. + + Lots of decisions to make. If we are copying less than a cache + line we won't be here long. If we are not on a cache line + boundary we need to get there. And then we need to figure out + how many cache lines ahead to pre-touch. + + r3 - return value (always) + r4 - current source addr + r5 - copy length + r6 - current dest addr + */ + + + .align 4 +L(dst_aligned): + + + cmpd cr5,r5,r10 /* Less than a cacheline to go? */ + + neg r7,r6 /* How far to next cacheline bdy? */ + + addi r6,r6,-8 /* prepare for stdu */ + cmpdi cr0,r9,128 + addi r4,r4,-8 /* prepare for ldu */ + + + ble+ cr5,L(lessthancacheline) + + beq- cr0,L(big_lines) /* 128 byte line code */ + + + + /* More than a cacheline left to go, and using 64 byte cachelines */ + + clrldi r7,r7,64-6 /* How far to next cacheline bdy? */ + + cmpldi cr6,r7,0 /* Are we on a cacheline bdy already? */ + + /* Reduce total len by what it takes to get to the next cache line */ + subf r5,r7,r5 + srdi r7,r7,4 /* How many qws to get to the line bdy? */ + + /* How many full cache lines to copy after getting to a line bdy? */ + srdi r10,r5,6 + + cmpldi r10,0 /* If no full cache lines to copy ... */ + li r11,0 /* number cachelines to copy with prefetch */ + beq L(nocacheprefetch) + + + /* We are here because we have at least one full cache line to copy, + and therefore some pre-touching to do. */ + + cmpldi r10,PREFETCH_AHEAD + li r12,64+8 /* prefetch distance */ + ble L(lessthanmaxprefetch) + + /* We can only do so much pre-fetching. R11 will have the count of + lines left to prefetch after the initial batch of prefetches + are executed. */ + + subi r11,r10,PREFETCH_AHEAD + li r10,PREFETCH_AHEAD + +L(lessthanmaxprefetch): + mtctr r10 + + /* At this point r10/ctr hold the number of lines to prefetch in this + initial batch, and r11 holds any remainder. */ + +L(prefetchSRC): + dcbt r12,r4 + addi r12,r12,64 + bdnz L(prefetchSRC) + + + /* Prefetching is done, or was not needed. + + cr6 - are we on a cacheline boundary already? + r7 - number of quadwords to the next cacheline boundary + */ + +L(nocacheprefetch): + mtctr r7 + + cmpldi cr1,r5,64 /* Less than a cache line to copy? */ + + /* How many bytes are left after we copy whatever full + cache lines we can get? */ + clrldi r5,r5,64-6 + + beq cr6,L(cachelinealigned) + + + /* Copy quadwords up to the next cacheline boundary */ + +L(aligntocacheline): + ld r9,0x08(r4) + ld r7,0x10(r4) + addi r4,r4,0x10 + std r9,0x08(r6) + stdu r7,0x10(r6) + bdnz L(aligntocacheline) + + + .align 4 +L(cachelinealigned): /* copy while cache lines */ + + blt- cr1,L(lessthancacheline) /* size <64 */ + +L(outerloop): + cmpdi r11,0 + mtctr r11 + beq- L(endloop) + + li r11,64*ZERO_AHEAD +8 /* DCBZ dist */ + + .align 4 + /* Copy whole cachelines, optimized by prefetching SRC cacheline */ +L(loop): /* Copy aligned body */ + dcbt r12,r4 /* PREFETCH SOURCE some cache lines ahead */ + ld r9, 0x08(r4) + dcbz r11,r6 + ld r7, 0x10(r4) + ld r8, 0x18(r4) + ld r0, 0x20(r4) + std r9, 0x08(r6) + std r7, 0x10(r6) + std r8, 0x18(r6) + std r0, 0x20(r6) + ld r9, 0x28(r4) + ld r7, 0x30(r4) + ld r8, 0x38(r4) + ld r0, 0x40(r4) + addi r4, r4,0x40 + std r9, 0x28(r6) + std r7, 0x30(r6) + std r8, 0x38(r6) + stdu r0, 0x40(r6) + + bdnz L(loop) + + +L(endloop): + cmpdi r10,0 + beq- L(endloop2) + mtctr r10 + +L(loop2): /* Copy aligned body */ + ld r9, 0x08(r4) + ld r7, 0x10(r4) + ld r8, 0x18(r4) + ld r0, 0x20(r4) + std r9, 0x08(r6) + std r7, 0x10(r6) + std r8, 0x18(r6) + std r0, 0x20(r6) + ld r9, 0x28(r4) + ld r7, 0x30(r4) + ld r8, 0x38(r4) + ld r0, 0x40(r4) + addi r4, r4,0x40 + std r9, 0x28(r6) + std r7, 0x30(r6) + std r8, 0x38(r6) + stdu r0, 0x40(r6) + + bdnz L(loop2) +L(endloop2): + + + .align 4 +L(lessthancacheline): /* Was there less than cache to do ? */ + cmpldi cr0,r5,16 + srdi r7,r5,4 /* divide size by 16 */ + blt- L(do_lt16) + mtctr r7 + +L(copy_remaining): + ld r8,0x08(r4) + ld r7,0x10(r4) + addi r4,r4,0x10 + std r8,0x08(r6) + stdu r7,0x10(r6) + bdnz L(copy_remaining) + +L(do_lt16): /* less than 16 ? */ + cmpldi cr0,r5,0 /* copy remaining bytes (0-15) */ + beqlr+ /* no rest to copy */ + addi r4,r4,8 + addi r6,r6,8 + +L(shortcopy): /* SIMPLE COPY to handle size =< 15 bytes */ + mtcrf 0x01,r5 + sub r7,r4,r6 + bf- cr7*4+0,8f + ldx r0,r7,r6 /* copy 8 byte */ + std r0,0(r6) + addi r6,r6,8 +8: + bf cr7*4+1,4f + lwzx r0,r7,r6 /* copy 4 byte */ + stw r0,0(r6) + addi r6,r6,4 +4: + bf cr7*4+2,2f + lhzx r0,r7,r6 /* copy 2 byte */ + sth r0,0(r6) + addi r6,r6,2 +2: + bf cr7*4+3,1f + lbzx r0,r7,r6 /* copy 1 byte */ + stb r0,0(r6) +1: + blr + + + + + + /* Similar to above, but for use with 128 byte lines. */ + + +L(big_lines): + + clrldi r7,r7,64-7 /* How far to next cacheline bdy? */ + + cmpldi cr6,r7,0 /* Are we on a cacheline bdy already? */ + + /* Reduce total len by what it takes to get to the next cache line */ + subf r5,r7,r5 + srdi r7,r7,4 /* How many qws to get to the line bdy? */ + + /* How many full cache lines to copy after getting to a line bdy? */ + srdi r10,r5,7 + + cmpldi r10,0 /* If no full cache lines to copy ... */ + li r11,0 /* number cachelines to copy with prefetch */ + beq L(nocacheprefetch_128) + + + /* We are here because we have at least one full cache line to copy, + and therefore some pre-touching to do. */ + + cmpldi r10,PREFETCH_AHEAD + li r12,128+8 /* prefetch distance */ + ble L(lessthanmaxprefetch_128) + + /* We can only do so much pre-fetching. R11 will have the count of + lines left to prefetch after the initial batch of prefetches + are executed. */ + + subi r11,r10,PREFETCH_AHEAD + li r10,PREFETCH_AHEAD + +L(lessthanmaxprefetch_128): + mtctr r10 + + /* At this point r10/ctr hold the number of lines to prefetch in this + initial batch, and r11 holds any remainder. */ + +L(prefetchSRC_128): + dcbt r12,r4 + addi r12,r12,128 + bdnz L(prefetchSRC_128) + + + /* Prefetching is done, or was not needed. + + cr6 - are we on a cacheline boundary already? + r7 - number of quadwords to the next cacheline boundary + */ + +L(nocacheprefetch_128): + mtctr r7 + + cmpldi cr1,r5,128 /* Less than a cache line to copy? */ + + /* How many bytes are left after we copy whatever full + cache lines we can get? */ + clrldi r5,r5,64-7 + + beq cr6,L(cachelinealigned_128) + + + /* Copy quadwords up to the next cacheline boundary */ + +L(aligntocacheline_128): + ld r9,0x08(r4) + ld r7,0x10(r4) + addi r4,r4,0x10 + std r9,0x08(r6) + stdu r7,0x10(r6) + bdnz L(aligntocacheline_128) + + +L(cachelinealigned_128): /* copy while cache lines */ + + blt- cr1,L(lessthancacheline) /* size <128 */ + +L(outerloop_128): + cmpdi r11,0 + mtctr r11 + beq- L(endloop_128) + + li r11,128*ZERO_AHEAD +8 /* DCBZ dist */ + + .align 4 + /* Copy whole cachelines, optimized by prefetching SRC cacheline */ +L(loop_128): /* Copy aligned body */ + dcbt r12,r4 /* PREFETCH SOURCE some cache lines ahead */ + ld r9, 0x08(r4) + dcbz r11,r6 + ld r7, 0x10(r4) + ld r8, 0x18(r4) + ld r0, 0x20(r4) + std r9, 0x08(r6) + std r7, 0x10(r6) + std r8, 0x18(r6) + std r0, 0x20(r6) + ld r9, 0x28(r4) + ld r7, 0x30(r4) + ld r8, 0x38(r4) + ld r0, 0x40(r4) + std r9, 0x28(r6) + std r7, 0x30(r6) + std r8, 0x38(r6) + std r0, 0x40(r6) + ld r9, 0x48(r4) + ld r7, 0x50(r4) + ld r8, 0x58(r4) + ld r0, 0x60(r4) + std r9, 0x48(r6) + std r7, 0x50(r6) + std r8, 0x58(r6) + std r0, 0x60(r6) + ld r9, 0x68(r4) + ld r7, 0x70(r4) + ld r8, 0x78(r4) + ld r0, 0x80(r4) + addi r4, r4,0x80 + std r9, 0x68(r6) + std r7, 0x70(r6) + std r8, 0x78(r6) + stdu r0, 0x80(r6) + + bdnz L(loop_128) + + +L(endloop_128): + cmpdi r10,0 + beq- L(endloop2_128) + mtctr r10 + +L(loop2_128): /* Copy aligned body */ + ld r9, 0x08(r4) + ld r7, 0x10(r4) + ld r8, 0x18(r4) + ld r0, 0x20(r4) + std r9, 0x08(r6) + std r7, 0x10(r6) + std r8, 0x18(r6) + std r0, 0x20(r6) + ld r9, 0x28(r4) + ld r7, 0x30(r4) + ld r8, 0x38(r4) + ld r0, 0x40(r4) + std r9, 0x28(r6) + std r7, 0x30(r6) + std r8, 0x38(r6) + std r0, 0x40(r6) + ld r9, 0x48(r4) + ld r7, 0x50(r4) + ld r8, 0x58(r4) + ld r0, 0x60(r4) + std r9, 0x48(r6) + std r7, 0x50(r6) + std r8, 0x58(r6) + std r0, 0x60(r6) + ld r9, 0x68(r4) + ld r7, 0x70(r4) + ld r8, 0x78(r4) + ld r0, 0x80(r4) + addi r4, r4,0x80 + std r9, 0x68(r6) + std r7, 0x70(r6) + std r8, 0x78(r6) + stdu r0, 0x80(r6) + + bdnz L(loop2_128) +L(endloop2_128): + + b L(lessthancacheline) + + +END_GEN_TB (BP_SYM (memcpy),TB_TOCLESS) +libc_hidden_builtin_def (memcpy) |