diff options
Diffstat (limited to 'sysdeps/powerpc/powerpc64/power7/strcpy.S')
| -rw-r--r-- | sysdeps/powerpc/powerpc64/power7/strcpy.S | 274 |
1 files changed, 274 insertions, 0 deletions
diff --git a/sysdeps/powerpc/powerpc64/power7/strcpy.S b/sysdeps/powerpc/powerpc64/power7/strcpy.S new file mode 100644 index 0000000000..5c341a1483 --- /dev/null +++ b/sysdeps/powerpc/powerpc64/power7/strcpy.S @@ -0,0 +1,274 @@ +/* Optimized strcpy/stpcpy implementation for PowerPC64/POWER7. + Copyright (C) 2013 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> + +/* Implements the function + + char * [r3] strcpy (char *dest [r3], const char *src [r4]) + + or + + char * [r3] strcpy (char *dest [r3], const char *src [r4]) + + if USE_AS_STPCPY is defined. It tries to use aligned memory accesses + when possible using the following algorithm: + + if (((((uintptr_t)dst & 0x7UL) == 0) && ((uintptr_t)src & 0x7UL) == 0)) + goto aligned_doubleword_copy; + if (((((uintptr_t)dst & 0x3UL) == 0) && ((uintptr_t)src & 0x3UL) == 0)) + goto aligned_word_copy; + if (((uintptr_t)dst & 0x7UL) == ((uintptr_t)src & 0x7UL)) + goto same_alignment; + goto unaligned; + + The aligned comparison are made using cmpb instructions. */ + +#ifdef USE_AS_STPCPY +# define FUNC_NAME __stpcpy +#else +# define FUNC_NAME strcpy +#endif + + .machine power7 +EALIGN (FUNC_NAME, 4, 0) + CALL_MCOUNT 2 + +#define rTMP r0 +#ifdef USE_AS_STPCPY +#define rRTN r3 /* pointer to previous word/doubleword in dest */ +#else +#define rRTN r12 /* pointer to previous word/doubleword in dest */ +#endif +#define rSRC r4 /* pointer to previous word/doubleword in src */ +#define rMASK r5 /* mask 0xffffffff | 0xffffffffffffffff */ +#define rWORD r6 /* current word from src */ +#define rALT r7 /* alternate word from src */ +#define rRTNAL r8 /* alignment of return pointer */ +#define rSRCAL r9 /* alignment of source pointer */ +#define rALCNT r10 /* bytes to read to reach 8 bytes alignment */ +#define rSUBAL r11 /* doubleword minus unaligned displacement */ + +#ifndef USE_AS_STPCPY +/* Save the dst pointer to use as return value. */ + mr rRTN, r3 +#endif + or rTMP, rSRC, rRTN + clrldi. rTMP, rTMP, 61 + bne L(check_word_alignment) + b L(aligned_doubleword_copy) + +L(same_alignment): +/* Src and dst with same alignment: align both to doubleword. */ + mr rALCNT, rRTN + lbz rWORD, 0(rSRC) + subfic rSUBAL, rRTNAL, 8 + addi rRTN, rRTN, 1 + addi rSRC, rSRC, 1 + cmpdi cr7, rWORD, 0 + stb rWORD, 0(rALCNT) + beq cr7, L(s2) + + add rALCNT, rALCNT, rSUBAL + subf rALCNT, rRTN, rALCNT + addi rALCNT, rALCNT, 1 + mtctr rALCNT + b L(s1) + + .align 4 +L(s0): + addi rSRC, rSRC, 1 + lbz rWORD, -1(rSRC) + cmpdi cr7, rWORD, 0 + stb rWORD, -1(rALCNT) + beqlr cr7 + mr rRTN, rALCNT +L(s1): + addi rALCNT, rRTN,1 + bdnz L(s0) + b L(aligned_doubleword_copy) + .align 4 +L(s2): + mr rRTN, rALCNT + blr + +/* For doubleword aligned memory, operate using doubleword load and stores. */ + .align 4 +L(aligned_doubleword_copy): + li rMASK, 0 + addi rRTN, rRTN, -8 + ld rWORD, 0(rSRC) + b L(g2) + + .align 4 +L(g0): ldu rALT, 8(rSRC) + stdu rWORD, 8(rRTN) + cmpb rTMP, rALT, rMASK + cmpdi rTMP, 0 + bne L(g1) + ldu rWORD, 8(rSRC) + stdu rALT, 8(rRTN) +L(g2): cmpb rTMP, rWORD, rMASK + cmpdi rTMP, 0 /* If rTMP is 0, no null's have been found. */ + beq L(g0) + + mr rALT, rWORD +/* We've hit the end of the string. Do the rest byte-by-byte. */ +L(g1): +#ifdef __LITTLE_ENDIAN__ + extrdi. rTMP, rALT, 8, 56 + stbu rALT, 8(rRTN) + beqlr- + extrdi. rTMP, rALT, 8, 48 + stbu rTMP, 1(rRTN) + beqlr- + extrdi. rTMP, rALT, 8, 40 + stbu rTMP, 1(rRTN) + beqlr- + extrdi. rTMP, rALT, 8, 32 + stbu rTMP, 1(rRTN) + beqlr- + extrdi. rTMP, rALT, 8, 24 + stbu rTMP, 1(rRTN) + beqlr- + extrdi. rTMP, rALT, 8, 16 + stbu rTMP, 1(rRTN) + beqlr- + extrdi. rTMP, rALT, 8, 8 + stbu rTMP, 1(rRTN) + beqlr- + extrdi rTMP, rALT, 8, 0 + stbu rTMP, 1(rRTN) +#else + extrdi. rTMP, rALT, 8, 0 + stbu rTMP, 8(rRTN) + beqlr + extrdi. rTMP, rALT, 8, 8 + stbu rTMP, 1(rRTN) + beqlr + extrdi. rTMP, rALT, 8, 16 + stbu rTMP, 1(rRTN) + beqlr + extrdi. rTMP, rALT, 8, 24 + stbu rTMP, 1(rRTN) + beqlr + extrdi. rTMP, rALT, 8, 32 + stbu rTMP, 1(rRTN) + beqlr + extrdi. rTMP, rALT, 8, 40 + stbu rTMP, 1(rRTN) + beqlr + extrdi. rTMP, rALT, 8, 48 + stbu rTMP, 1(rRTN) + beqlr + stbu rALT, 1(rRTN) +#endif + blr + +L(check_word_alignment): + clrldi. rTMP, rTMP, 62 + beq L(aligned_word_copy) + rldicl rRTNAL, rRTN, 0, 61 + rldicl rSRCAL, rSRC, 0, 61 + cmpld cr7, rSRCAL, rRTNAL + beq cr7, L(same_alignment) + b L(unaligned) + +/* For word aligned memory, operate using word load and stores. */ + .align 4 +L(aligned_word_copy): + li rMASK, 0 + addi rRTN, rRTN, -4 + lwz rWORD, 0(rSRC) + b L(g5) + + .align 4 +L(g3): lwzu rALT, 4(rSRC) + stwu rWORD, 4(rRTN) + cmpb rTMP, rALT, rMASK + cmpwi rTMP, 0 + bne L(g4) + lwzu rWORD, 4(rSRC) + stwu rALT, 4(rRTN) +L(g5): cmpb rTMP, rWORD, rMASK + cmpwi rTMP, 0 /* If rTMP is 0, no null in word. */ + beq L(g3) + + mr rALT, rWORD +/* We've hit the end of the string. Do the rest byte-by-byte. */ +L(g4): +#ifdef __LITTLE_ENDIAN__ + rlwinm. rTMP, rALT, 0, 24, 31 + stbu rALT, 4(rRTN) + beqlr- + rlwinm. rTMP, rALT, 24, 24, 31 + stbu rTMP, 1(rRTN) + beqlr- + rlwinm. rTMP, rALT, 16, 24, 31 + stbu rTMP, 1(rRTN) + beqlr- + rlwinm rTMP, rALT, 8, 24, 31 + stbu rTMP, 1(rRTN) +#else + rlwinm. rTMP, rALT, 8, 24, 31 + stbu rTMP, 4(rRTN) + beqlr + rlwinm. rTMP, rALT, 16, 24, 31 + stbu rTMP, 1(rRTN) + beqlr + rlwinm. rTMP, rALT, 24, 24, 31 + stbu rTMP, 1(rRTN) + beqlr + stbu rALT, 1(rRTN) +#endif + blr + +/* Oh well. In this case, we just do a byte-by-byte copy. */ + .align 4 +L(unaligned): + lbz rWORD, 0(rSRC) + addi rRTN, rRTN, -1 + cmpdi rWORD, 0 + beq L(u2) + + .align 5 +L(u0): lbzu rALT, 1(rSRC) + stbu rWORD, 1(rRTN) + cmpdi rALT, 0 + beq L(u1) + lbzu rWORD, 1(rSRC) + stbu rALT, 1(rRTN) + cmpdi rWORD, 0 + beq L(u2) + lbzu rALT, 1(rSRC) + stbu rWORD, 1(rRTN) + cmpdi rALT, 0 + beq L(u1) + lbzu rWORD, 1(rSRC) + stbu rALT, 1(rRTN) + cmpdi rWORD, 0 + bne L(u0) +L(u2): stbu rWORD, 1(rRTN) + blr +L(u1): stbu rALT, 1(rRTN) + blr +END (FUNC_NAME) + +#ifndef USE_AS_STPCPY +libc_hidden_builtin_def (strcpy) +#endif |