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author | Adhemerval Zanella <azanella@linux.vnet.ibm.com> | 2014-11-19 15:24:55 -0500 |
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committer | Adhemerval Zanella <azanella@linux.vnet.ibm.com> | 2014-12-02 07:16:24 -0500 |
commit | bb2542e0ae6f82197e804e7e9b78fed461553fc0 (patch) | |
tree | 2e62b412d0e0991663d888dd31b214c0c69b5f5c /sysdeps/powerpc/powerpc64/strcspn.S | |
parent | 2e8a2de2dafa3238b5b58eecb407af6825a780cd (diff) | |
download | glibc-bb2542e0ae6f82197e804e7e9b78fed461553fc0.tar.gz glibc-bb2542e0ae6f82197e804e7e9b78fed461553fc0.tar.xz glibc-bb2542e0ae6f82197e804e7e9b78fed461553fc0.zip |
powerpc: Add powerpc64 strcspn optimization
This patch makes the POWER7 optimized strcspn generic by using default doubleword stores to zero the hash, instead of VSX instructions. Performance on POWER7/POWER8 does not change.
Diffstat (limited to 'sysdeps/powerpc/powerpc64/strcspn.S')
-rw-r--r-- | sysdeps/powerpc/powerpc64/strcspn.S | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/sysdeps/powerpc/powerpc64/strcspn.S b/sysdeps/powerpc/powerpc64/strcspn.S new file mode 100644 index 0000000000..1121930b15 --- /dev/null +++ b/sysdeps/powerpc/powerpc64/strcspn.S @@ -0,0 +1,127 @@ +/* Optimized strcspn implementation for PowerPC64. + Copyright (C) 2014 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> + +/* size_t [r3] strcspn (const char [r4] *s, const char [r5] *reject) */ + +EALIGN (strcspn, 4, 0) + CALL_MCOUNT 3 + + /* The idea to speed up the algorithm is to create a lookup table + for fast check if input character should be considered. For ASCII + or ISO-8859-X character sets it has 256 positions. */ + + /* PPC64 ELF ABI stack is aligned to 16 bytes. */ + addi r9,r1,-256 + /* Clear the table with 0 values */ + li r6, 0 + li r8, 4 + mtctr r8 + mr r10, r9 + .align 4 +L(zerohash): + std r6, 0(r10) + std r6, 8(r10) + std r6, 16(r10) + std r6, 24(r10) + std r6, 32(r10) + std r6, 40(r10) + std r6, 48(r10) + std r6, 56(r10) + addi r10, r10, 64 + bdnz L(zerohash) + + lbz r10,0(r4) + cmpdi cr7,r10,0 /* reject[0] == '\0' ? */ + li r8,1 + beq cr7,L(finish_table) /* If reject[0] == '\0' skip */ + + /* Initialize the table as: + for (i=0; reject[i]; i++ + table[reject[i]]] = 1 */ + .align 4 +L(init_table): + stbx r8,r9,r10 + lbzu r10,1(r4) + cmpdi cr7,r10,0 /* If reject[0] == '\0' finish */ + bne cr7,L(init_table) +L(finish_table): + /* set table[0] = 1 */ + li r10,1 + stb r10,0(r9) + li r10,0 + b L(mainloop) + + /* Unrool the loop 4 times and check using the table as: + i = 0; + while (1) + { + if (table[input[i++]] == 1) + return i - 1; + if (table[input[i++]] == 1) + return i - 1; + if (table[input[i++]] == 1) + return i - 1; + if (table[input[i++]] == 1) + return i - 1; + } */ + .align 4 +L(unroll): + lbz r8,1(r3) + addi r10,r10,4 + lbzx r8,r9,r8 + cmpwi r7,r8,1 + beq cr7,L(end) + lbz r8,2(r3) + addi r3,r3,4 + lbzx r8,r9,r8 + cmpwi cr7,r8,1 + beq cr7,L(end2) + lbz r8,3(r7) + lbzx r8,r9,r8 + cmpwi cr7,r8,1 + beq cr7,L(end3) +L(mainloop): + lbz r8,0(r3) + mr r7,r3 + addi r6,r10,1 + addi r4,r10,2 + addi r5,r10,3 + lbzx r8,r9,8 + cmpwi cr7,r8,1 + bne cr7,L(unroll) + mr r3,r10 + blr + + .align 4 +L(end): + mr r3,r6 + blr + + .align 4 +L(end2): + mr r3,r4 + blr + + .align 4 +L(end3): + mr r3,r5 + blr +END (strcspn) +libc_hidden_builtin_def (strcspn) |