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Diffstat (limited to 'sysdeps/s390/multiarch/wcpncpy-vx.S')
-rw-r--r-- | sysdeps/s390/multiarch/wcpncpy-vx.S | 222 |
1 files changed, 222 insertions, 0 deletions
diff --git a/sysdeps/s390/multiarch/wcpncpy-vx.S b/sysdeps/s390/multiarch/wcpncpy-vx.S new file mode 100644 index 0000000..142c19a --- /dev/null +++ b/sysdeps/s390/multiarch/wcpncpy-vx.S @@ -0,0 +1,222 @@ +/* Vector optimized 32/64 bit S/390 version of wcpncpy. + Copyright (C) 2015 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/>. */ + +#if defined HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc) + +# include "sysdep.h" +# include "asm-syntax.h" + + .text + +/* wchar_t * wcpncpy (wchar_t *dest, const wchar_t *src, size_t n) + Copies at most n characters of string src to dest + returning a pointer to its end or dest+n + if src is smaller than n. + + Register usage: + -%r0 = return value + -%r1 = zero byte index + -%r2 = curr dst pointer + -%r3 = curr src pointer + -%r4 = n + -%r5 = current_len + -%r6 = loaded bytes + -%r7 = border, tmp +*/ +ENTRY(__wcpncpy_vx) + .machine "z13" + .machinemode "zarch_nohighgprs" + +# if !defined __s390x__ + llgfr %r4,%r4 +# endif /* !defined __s390x__ */ + + clgfi %r4,0 + ber %r14 /* Nothing to do, if n == 0. */ + + vlbb %v16,0(%r3),6 /* Load s until next 4k-byte boundary. */ + + tmll %r3,3 /* Test if s is 4-byte aligned? */ + jne .Lfallback /* And use common-code variant if not. */ + + vlvgp %v31,%r6,%r7 /* Save registers. */ + lghi %r5,0 /* current_len = 0. */ + + lcbb %r6,0(%r3),6 /* Get bytes to 4k-byte boundary or 16. */ + llgfr %r6,%r6 /* Convert 32bit to 64bit. */ + + /* Check range of maxlen and convert to byte-count. */ +# ifdef __s390x__ + tmhh %r4,49152 /* Test bit 0 or 1 of maxlen. */ + lghi %r1,-4 /* Max byte-count is 18446744073709551612. */ +# else + tmlh %r4,49152 /* Test bit 0 or 1 of maxlen. */ + llilf %r1,4294967292 /* Max byte-count is 4294967292. */ +# endif /* !__s390x__ */ + sllg %r4,%r4,2 /* Convert character-count to byte-count. */ + locgrne %r4,%r1 /* Use max byte-count, if bit 0/1 was one. */ + + la %r0,0(%r4,%r2) /* Save destination pointer + n for return. */ + + clgrjle %r4,%r6,.Lremaining_v16 /* If n <= loaded-bytes + -> process remaining. */ + + /* n > loaded-byte-count */ + vfenezf %v17,%v16,%v16 /* Find element not equal with zero search. */ + vlgvb %r1,%v17,7 /* Load zero index or 16 if not found. */ + aghi %r1,3 /* Also copy remaining bytes of zero. */ + clrjl %r1,%r6,.Lfound_v16_store /* Found zero within loaded bytes, + copy and return. */ + + /* Align s to 16 byte. */ + risbgn %r7,%r3,60,128+63,0 /* %r3 = bits 60-63 of %r2 'and' 15. */ + lghi %r5,15 /* current_len = 15. */ + slr %r5,%r7 /* Compute highest index to 16byte boundary. */ + + /* Zero not found and n > loaded-byte-count. */ + vstl %v16,%r5,0(%r2) /* Copy loaded characters - no zero. */ + ahi %r5,1 /* Start loop at next character. */ + + /* Now we are 16byte aligned, so we can load a full vreg + without page fault. */ + lgr %r1,%r5 /* If %r5 + 64 < maxlen? -> loop64. */ + aghi %r1,64 + clgrjl %r1,%r4,.Lloop64 + + vl %v16,0(%r5,%r3) /* Load s. */ + clgijl %r4,17,.Lremaining_v16 /* If n <=16, + process remaining bytes. */ +.Llt64: + lgr %r7,%r4 + slgfi %r7,16 /* border_len = n - 16. */ + + clgrjhe %r5,%r7,.Lremaining_v16 /* If current_len >= border + then process remaining bytes. */ + vfenezfs %v17,%v16,%v16 /* Find element not equal with zero search. */ + je .Lfound_v16 /* Jump away if zero was found. */ + vl %v18,16(%r5,%r3) /* Load next part of s. */ + vst %v16,0(%r5,%r2) /* Store previous part without zero to dst. */ + aghi %r5,16 + + clgrjhe %r5,%r7,.Lremaining_v18 + vfenezfs %v17,%v18,%v18 + je .Lfound_v18 + vl %v16,16(%r5,%r3) + vst %v18,0(%r5,%r2) + aghi %r5,16 + + clgrjhe %r5,%r7,.Lremaining_v16 + vfenezfs %v17,%v16,%v16 + je .Lfound_v16 + vl %v18,16(%r5,%r3) + vst %v16,0(%r5,%r2) + aghi %r5,16 + +.Lremaining_v18: + vlr %v16,%v18 +.Lremaining_v16: + /* v16 contains the remaining bytes [1...16]. + Store remaining bytes and append string-termination. */ + vfenezf %v17,%v16,%v16 /* Find element not equal with zero search. */ + slgrk %r7,%r4,%r5 /* Remaining bytes = maxlen - current_len */ + aghi %r7,-1 /* vstl needs highest index. */ + la %r2,0(%r5,%r2) /* vstl has no index register. */ + vlgvb %r1,%v17,7 /* Load zero index or 16 if not found. */ + aghi %r1,3 /* Also copy remaining bytes of zero. */ + /* Zero in remaining bytes? -> jump away (zero-index <= max-index). */ + clrjle %r1,%r7,.Lfound_v16_store + vstl %v16,%r7,0(%r2) /* Store remaining bytes without null + termination! */ +.Lend: + /* Restore saved registers. */ + vlgvg %r6,%v31,0 + vlgvg %r7,%v31,1 + lgr %r2,%r0 /* Load saved dest-ptr. */ + br %r14 + +.Lfound_v16_32: + aghi %r5,32 + j .Lfound_v16 +.Lfound_v18_48: + aghi %r5,32 +.Lfound_v18_16: + aghi %r5,16 +.Lfound_v18: + vlr %v16,%v18 +.Lfound_v16: + /* v16 contains a zero. Store remaining bytes to zero. current_len + has not reached border, thus checking for n is not needed! */ + vlgvb %r1,%v17,7 /* Load byte index of zero. */ + la %r2,0(%r5,%r2) /* vstl has no support for index-register. */ + aghi %r1,3 /* Also copy remaining bytes of zero. */ +.Lfound_v16_store: + vstl %v16,%r1,0(%r2) /* Copy characters including zero. */ + /* Fill remaining bytes with zero - remaining byte count always > 0. */ + algr %r5,%r1 /* Remaining bytes (=%r4) = ... */ + slgr %r4,%r5 /* = n - (currlen + zero_index + 1) */ + la %r2,0(%r1,%r2) /* Pointer to zero. start filling beyond. */ + lay %r0,-3(%r2) /* Save return-pointer to found zero. */ + clgije %r4,1,.Lend /* Skip zero-filling, if found-zero is last + possible character. + (1 is substracted from r4 below!). */ + aghi %r4,-2 /* mvc with exrl needs count - 1. + (additional -1, see remaining bytes above) */ + srlg %r6,%r4,8 /* Split into 256 byte blocks. */ + ltgr %r6,%r6 + je .Lzero_lt256 +.Lzero_loop256: + mvc 1(256,%r2),0(%r2) /* Fill 256 zeros at once. */ + la %r2,256(%r2) + brctg %r6,.Lzero_loop256 /* Loop until all blocks are processed. */ +.Lzero_lt256: + exrl %r4,.Lmvc_lt256 + j .Lend +.Lmvc_lt256: + mvc 1(1,%r2),0(%r2) + + /* Find zero in 16byte aligned loop. */ +.Lloop64: + vl %v16,0(%r5,%r3) + vfenezfs %v17,%v16,%v16 /* Find element not equal with zero search. */ + je .Lfound_v16 /* Jump away if zero was found. */ + vl %v18,16(%r5,%r3) /* Load next part of s. */ + vst %v16,0(%r5,%r2) /* Store previous part without zero to dst. */ + vfenezfs %v17,%v18,%v18 + je .Lfound_v18_16 + vl %v16,32(%r5,%r3) + vst %v18,16(%r5,%r2) + vfenezfs %v17,%v16,%v16 + je .Lfound_v16_32 + vl %v18,48(%r5,%r3) + vst %v16,32(%r5,%r2) + vfenezfs %v17,%v18,%v18 + je .Lfound_v18_48 + vst %v18,48(%r5,%r2) + + aghi %r5,64 + lgr %r1,%r5 /* If %r5 + 64 < maxlen? -> loop64. */ + aghi %r1,64 + clgrjl %r1,%r4,.Lloop64 + + vl %v16,0(%r5,%r3) /* Load s. */ + j .Llt64 + +.Lfallback: + jg __wcpncpy_c +END(__wcpncpy_vx) +#endif /* HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc) */ |