diff options
Diffstat (limited to 'sysdeps/alpha')
-rw-r--r-- | sysdeps/alpha/Makefile | 14 | ||||
-rw-r--r-- | sysdeps/alpha/bzero.S | 113 | ||||
-rw-r--r-- | sysdeps/alpha/memset.S | 130 | ||||
-rw-r--r-- | sysdeps/alpha/stpcpy.S | 49 | ||||
-rw-r--r-- | sysdeps/alpha/stpncpy.S | 103 | ||||
-rw-r--r-- | sysdeps/alpha/strcat.S | 66 | ||||
-rw-r--r-- | sysdeps/alpha/strchr.S | 88 | ||||
-rw-r--r-- | sysdeps/alpha/strcpy.S | 36 | ||||
-rw-r--r-- | sysdeps/alpha/strncat.S | 90 | ||||
-rw-r--r-- | sysdeps/alpha/strncpy.S | 85 | ||||
-rw-r--r-- | sysdeps/alpha/strrchr.S | 104 | ||||
-rw-r--r-- | sysdeps/alpha/stxcpy.S | 307 | ||||
-rw-r--r-- | sysdeps/alpha/stxncpy.S | 350 |
13 files changed, 1530 insertions, 5 deletions
diff --git a/sysdeps/alpha/Makefile b/sysdeps/alpha/Makefile index 6aaedea..45babb6 100644 --- a/sysdeps/alpha/Makefile +++ b/sysdeps/alpha/Makefile @@ -21,17 +21,21 @@ sysdep_routines += _mcount endif ifeq ($(subdir),setjmp) -sysdep_routines := $(sysdep_routines) setjmp_aux +sysdep_routines += setjmp_aux endif ifeq ($(subdir),gnulib) -routines = $(divrem) -endif # gnulib +sysdep_routines += $(divrem) +endif + +ifeq ($(subdir),string) +sysdep_routines += stxcpy stxncpy +endif ifeq ($(subdir),elf) -# The ld.so code cannot use literals until it self-relocates. +# The ld.so startup code cannot use literals until it self-relocates. ifeq ($(elf),yes) -CFLAGS-rtld.c = -mbuild-constants + CFLAGS-rtld.c = -mbuild-constants endif # The rest of ld.so shouldn't use FP regs for block moves so # that the lazy link trampoline doesn't have to save them. diff --git a/sysdeps/alpha/bzero.S b/sysdeps/alpha/bzero.S new file mode 100644 index 0000000..fffa53d --- /dev/null +++ b/sysdeps/alpha/bzero.S @@ -0,0 +1,113 @@ +/* Copyright (C) 1996 Free Software Foundation, Inc. + Contributed by Richard Henderson (rth@tamu.edu) + +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 Library General Public License as +published by the Free Software Foundation; either version 2 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 +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +/* Fill a block of memory with zeros. Optimized for the Alpha architecture: + + - memory accessed as aligned quadwords only + - destination memory not read unless needed for good cache behaviour + - basic blocks arranged to optimize branch prediction for full-quadword + aligned memory blocks. + - partial head and tail quadwords constructed with byte-mask instructions + + This is generally scheduled for the EV5 (got to look out for my own + interests :-), but with EV4 needs in mind. There *should* be no more + stalls for the EV4 than there are for the EV5. +*/ + + +#include <sysdep.h> + + .set noat + .set noreorder + + .text + +/* There is a problem with either gdb (as of 4.16) or gas (as of 2.7) that + doesn't like putting the entry point for a procedure somewhere in the + middle of the procedure descriptor. Work around this by putting the main + loop in its own procedure descriptor. */ + + /* On entry to this basic block: + t3 == loop counter + t4 == bytes in partial final word + a0 == possibly misaligned destination pointer */ + + .ent bzero_loop + .align 3 +bzero_loop: + .frame sp, 0, ra, 0 + .prologue 0 + + beq t3, $tail # + blbc t3, 0f # skip single store if count even + + stq_u zero, 0(a0) # e0 : store one word + subq t3, 1, t3 # .. e1 : + addq a0, 8, a0 # e0 : + beq t3, $tail # .. e1 : + +0: stq_u zero, 0(a0) # e0 : store two words + subq t3, 2, t3 # .. e1 : + stq_u zero, 8(a0) # e0 : + addq a0, 16, a0 # .. e1 : + bne t3, 0b # e1 : + +$tail: bne t4, 1f # is there a tail to do? + ret # no + +1: ldq_u t0, 0(a0) # yes, load original data + mskqh t0, t4, t0 # + stq_u t0, 0(a0) # + ret # + + .end bzero_loop + +ENTRY(bzero) + .prologue 0 + + mov a0, v0 # e0 : move return value in place + beq a1, $done # .. e1 : early exit for zero-length store + and a0, 7, t1 # e0 : + addq a1, t1, a1 # e1 : add dest misalignment to count + srl a1, 3, t3 # e0 : loop = count >> 3 + and a1, 7, t4 # .. e1 : find number of bytes in tail + unop # : + beq t1, bzero_loop # e1 : aligned head, jump right in + + ldq_u t0, 0(a0) # e0 : load original data to mask into + cmpult a1, 8, t2 # .. e1 : is this a sub-word set? + bne t2, $oneq # e1 : + + mskql t0, a0, t0 # e0 : we span words. finish this partial + subq t3, 1, t3 # e0 : + addq a0, 8, a0 # .. e1 : + stq_u t0, -8(a0) # e0 : + br bzero_loop # .. e1 : + + .align 3 +$oneq: + mskql t0, a0, t2 # e0 : + mskqh t0, a1, t3 # e0 : + or t2, t3, t0 # e1 : + stq_u t0, 0(a0) # e0 : + +$done: ret + + END(bzero) diff --git a/sysdeps/alpha/memset.S b/sysdeps/alpha/memset.S new file mode 100644 index 0000000..55271f0 --- /dev/null +++ b/sysdeps/alpha/memset.S @@ -0,0 +1,130 @@ +/* Copyright (C) 1996 Free Software Foundation, Inc. + Contributed by Richard Henderson (rth@tamu.edu) + +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 Library General Public License as +published by the Free Software Foundation; either version 2 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 +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +/* Fill a block of memory with a character. Optimized for the Alpha + architecture: + + - memory accessed as aligned quadwords only + - destination memory not read unless needed for good cache behaviour + - basic blocks arranged to optimize branch prediction for full-quadword + aligned memory blocks. + - partial head and tail quadwords constructed with byte-mask instructions + + This is generally scheduled for the EV5 (got to look out for my own + interests :-), but with EV4 needs in mind. There *should* be no more + stalls for the EV4 than there are for the EV5. +*/ + + +#include <sysdep.h> + + .set noat + .set noreorder + + .text + +/* There is a problem with either gdb (as of 4.16) or gas (as of 2.7) that + doesn't like putting the entry point for a procedure somewhere in the + middle of the procedure descriptor. Work around this by putting the main + loop in its own procedure descriptor. */ + + /* On entry to this basic block: + t3 == loop counter + t4 == bytes in partial final word + a0 == possibly misaligned destination pointer + a1 == replicated source character */ + + .ent memset_loop + .align 3 +memset_loop: + .frame sp, 0, ra, 0 + .prologue 0 + + beq t3, $tail + blbc t3, 0f # skip single store if count even + + stq_u a1, 0(a0) # e0 : store one word + subq t3, 1, t3 # .. e1 : + addq a0, 8, a0 # e0 : + beq t3, $tail # .. e1 : + +0: stq_u a1, 0(a0) # e0 : store two words + subq t3, 2, t3 # .. e1 : + stq_u a1, 8(a0) # e0 : + addq a0, 16, a0 # .. e1 : + bne t3, 0b # e1 : + +$tail: bne t4, 1f # is there a tail to do? + ret # no + + .align 3 +1: ldq_u t0, 0(a0) # e1 : yes, load original data + mskql a1, t4, t1 # .. e0 : + mskqh t0, t4, t0 # e0 : + or t0, t1, t0 # e1 (stall) + stq_u t0, 0(a0) # e0 : + ret # .. e1 : + + .end memset_loop + +ENTRY(memset) + .prologue 0 + + zapnot a1, 1, a1 # e0 : zero extend input character + mov a0, v0 # .. e1 : move return value in place + sll a1, 8, t0 # e0 : begin replicating the char + beq a2, $done # .. e1 : early exit for zero-length store + or t0, a1, a1 # e0 : + and a0, 7, t1 # .. e1 : dest misalignment + sll a1, 16, t0 # e0 : + addq a2, t1, a2 # .. e1 : add dest misalignment to count + or t0, a1, a1 # e0 : + srl a2, 3, t3 # .. e1 : loop = count >> 3 + sll a1, 32, t0 # e0 : + and a2, 7, t4 # .. e1 : find number of bytes in tail + or t0, a1, a1 # e0 : character replication done + + beq t1, memset_loop # .. e1 : aligned head, jump right in + + ldq_u t0, 0(a0) # e1 : load original data to mask into + mskqh a1, a0, t1 # .. e0 : + + cmpult a2, 8, t2 # e0 : is this a sub-word set? + bne t2, $oneq # .. e1 (zdb) + + mskql t0, a0, t0 # e0 : we span words. finish this partial + subq t3, 1, t3 # .. e1 : + addq a0, 8, a0 # e0 : + or t0, t1, t0 # .. e1 : + stq_u t0, -8(a0) # e0 : + br memset_loop # .. e1 : + + .align 3 +$oneq: + mskql t1, a2, t1 # e0 : entire operation within one word + mskql t0, a0, t2 # e0 : + mskqh t0, a2, t3 # e0 : + or t1, t2, t0 # .. e1 : + or t0, t3, t0 # e1 : + stq_u t0, 0(a0) # e0 (stall) + +$done: ret + + END(memset) diff --git a/sysdeps/alpha/stpcpy.S b/sysdeps/alpha/stpcpy.S new file mode 100644 index 0000000..0dc44d3 --- /dev/null +++ b/sysdeps/alpha/stpcpy.S @@ -0,0 +1,49 @@ +/* Copyright (C) 1996 Free Software Foundation, Inc. + Contributed by Richard Henderson (rth@tamu.edu) + +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 Library General Public License as +published by the Free Software Foundation; either version 2 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 +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +/* Copy a null-terminated string from SRC to DST. Return a pointer + to the null-terminator in the source. */ + +#include <sysdep.h> + + .text + +ENTRY(__stpcpy) + ldgp gp, 0(pv) + .prologue 1 + + jsr t9, __stxcpy # do the work of the copy + + and t8, 0xf0, t2 # binary search for byte offset of the + and t8, 0xcc, t1 # last byte written. + and t8, 0xaa, t0 + andnot a0, 7, a0 + cmovne t2, 4, t2 + cmovne t1, 2, t1 + cmovne t0, 1, t0 + addq a0, t2, v0 + addq t0, t1, t0 + addq v0, t0, v0 + + ret + + END(__stpcpy) + +weak_alias (__stpcpy, stpcpy) diff --git a/sysdeps/alpha/stpncpy.S b/sysdeps/alpha/stpncpy.S new file mode 100644 index 0000000..50cda26 --- /dev/null +++ b/sysdeps/alpha/stpncpy.S @@ -0,0 +1,103 @@ +/* Copyright (C) 1996 Free Software Foundation, Inc. + Contributed by Richard Henderson (rth@tamu.edu) + +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 Library General Public License as +published by the Free Software Foundation; either version 2 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 +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +/* Copy no more than COUNT bytes of the null-terminated string from + SRC to DST. If SRC does not cover all of COUNT, the balance is + zeroed. Return the address of the terminating null in DEST, if + any, else DEST + COUNT. */ + +#include <sysdep.h> + + .set noat + .set noreorder + + .text + +ENTRY(__stpncpy) + ldgp gp, 0(pv) + .prologue 1 + + beq a2, $zerocount + jsr t9, __stxncpy # do the work of the copy + + and t8, 0xf0, t3 # binary search for byte offset of the + and t8, 0xcc, t2 # last byte written. + and t8, 0xaa, t1 + andnot a0, 7, v0 + cmovne t3, 4, t3 + cmovne t2, 2, t2 + cmovne t1, 1, t1 + addq v0, t3, v0 + addq t1, t2, t1 + addq v0, t1, v0 + + bne a2, $multiword # do we have full words left? + + .align 3 + zapnot t0, t8, t4 # e0 : was last byte a null? + subq t8, 1, t2 # .. e1 : + addq v0, 1, t5 # e0 : + subq t10, 1, t3 # .. e1 : + or t2, t8, t2 # e0 : clear the bits between the last + or t3, t10, t3 # .. e1 : written byte and the last byte in + andnot t3, t2, t3 # e0 : COUNT + cmovne t4, t5, v0 # .. e1 : if last written wasnt null, inc v0 + zap t0, t3, t0 # e0 : + stq_u t0, 0(a0) # e1 : + ret # .. e1 : + + .align 3 +$multiword: + subq t8, 1, t7 # e0 : clear the final bits in the prev + or t7, t8, t7 # e1 : word + zapnot t0, t7, t0 # e0 : + subq a2, 1, a2 # .. e1 : + stq_u t0, 0(a0) # e0 : + addq a0, 8, a0 # .. e1 : + + beq a2, 1f # e1 : + blbc a2, 0f # e1 : + + stq_u zero, 0(a0) # e0 : zero one word + subq a2, 1, a2 # .. e1 : + addq a0, 8, a0 # e0 : + beq a2, 1f # .. e1 : + +0: stq_u zero, 0(a0) # e0 : zero two words + subq a2, 2, a2 # .. e1 : + stq_u zero, 8(a0) # e0 : + addq a0, 16, a0 # .. e1 : + bne a2, 0b # e1 : + unop + +1: ldq_u t0, 0(a0) # e0 : clear the leading bits in the final + subq t10, 1, t7 # .. e1 : word + or t7, t10, t7 # e0 : + zap t0, t7, t0 # e1 (stall) + stq_u t0, 0(a0) # e0 : + ret # .. e1 : + +$zerocount: + mov a0, v0 + ret + + END(__stpncpy) + +weak_alias (__stpncpy, stpncpy) diff --git a/sysdeps/alpha/strcat.S b/sysdeps/alpha/strcat.S new file mode 100644 index 0000000..d3afff3 --- /dev/null +++ b/sysdeps/alpha/strcat.S @@ -0,0 +1,66 @@ +/* Copyright (C) 1996 Free Software Foundation, Inc. + Contributed by Richard Henderson (rth@tamu.edu) + +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 Library General Public License as +published by the Free Software Foundation; either version 2 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 +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +/* Append a null-terminated string from SRC to DST. */ + +#include <sysdep.h> + + .text + +ENTRY(strcat) + ldgp gp, 0(pv) + .prologue 1 + + mov a0, v0 # set up return value + + /* Find the end of the string. */ + + ldq_u t0, 0(a0) # load first quadword (a0 may be misaligned) + lda t1, -1(zero) + insqh t1, a0, t1 + andnot a0, 7, a0 + or t1, t0, t0 + cmpbge zero, t0, t1 # t1 <- bitmask: bit i == 1 <==> i-th byte == 0 + bne t1, $found + +$loop: ldq t0, 8(a0) + addq a0, 8, a0 # addr += 8 + cmpbge zero, t0, t1 + beq t1, $loop + +$found: negq t1, t2 # clear all but least set bit + and t1, t2, t1 + + and t1, 0xf0, t2 # binary search for that set bit + and t1, 0xcc, t3 + and t1, 0xaa, t4 + cmovne t2, 4, t2 + cmovne t3, 2, t3 + cmovne t4, 1, t4 + addq t2, t3, t2 + addq a0, t4, a0 + addq a0, t2, a0 + + /* Now do the append. */ + + jsr t9, __stxcpy + ret + + END(strcat) diff --git a/sysdeps/alpha/strchr.S b/sysdeps/alpha/strchr.S new file mode 100644 index 0000000..c26a843 --- /dev/null +++ b/sysdeps/alpha/strchr.S @@ -0,0 +1,88 @@ +/* Copyright (C) 1996 Free Software Foundation, Inc. + Contributed by Richard Henderson (rth@tamu.edu) + +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 Library General Public License as +published by the Free Software Foundation; either version 2 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 +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +/* Return the address of a given character within a null-terminated + string, or null if it is not found. + + This is generally scheduled for the EV5 (got to look out for my own + interests :-), but with EV4 needs in mind. There *should* be no more + stalls for the EV4 than there are for the EV5. +*/ + +#include <sysdep.h> + + .set noreorder + .set noat + +ENTRY(strchr) + .prologue 0 + + zapnot a1, 1, a1 # e0 : zero extend the search character + ldq_u t0, 0(a0) # .. e1 : load first quadword + sll a1, 8, t5 # e0 : replicate the search character + andnot a0, 7, v0 # .. e1 : align our loop pointer + or t5, a1, a1 # e0 : + lda t4, -1 # .. e1 : build garbage mask + sll a1, 16, t5 # e0 : + cmpbge zero, t0, t2 # .. e1 : bits set iff byte == zero + mskqh t4, a0, t4 # e0 : + or t5, a1, a1 # .. e1 : + sll a1, 32, t5 # e0 : + cmpbge zero, t4, t4 # .. e1 : bits set iff byte is garbage + or t5, a1, a1 # e0 : + xor t0, a1, t1 # .. e1 : make bytes == c zero + cmpbge zero, t1, t3 # e0 : bits set iff byte == c + or t2, t3, t0 # e1 : bits set iff char match or zero match + andnot t0, t4, t0 # e0 : clear garbage bits + bne t0, $found # .. e1 (zdb) + +$loop: ldq t0, 8(v0) # e0 : + addq v0, 8, v0 # .. e1 : + nop # e0 : + xor t0, a1, t1 # .. e1 (ev5 data stall) + cmpbge zero, t0, t2 # e0 : bits set iff byte == 0 + cmpbge zero, t1, t3 # .. e1 : bits set iff byte == c + or t2, t3, t0 # e0 : + beq t0, $loop # .. e1 (zdb) + +$found: negq t0, t1 # e0 : clear all but least set bit + and t0, t1, t0 # e1 (stall) + + and t0, t3, t1 # e0 : bit set iff byte was the char + beq t1, $retnull # .. e1 (zdb) + + and t0, 0xf0, t2 # e0 : binary search for that set bit + and t0, 0xcc, t3 # .. e1 : + and t0, 0xaa, t4 # e0 : + cmovne t2, 4, t2 # .. e1 : + cmovne t3, 2, t3 # e0 : + cmovne t4, 1, t4 # .. e1 : + addq t2, t3, t2 # e0 : + addq v0, t4, v0 # .. e1 : + addq v0, t2, v0 # e0 : + ret # .. e1 : + +$retnull: + mov zero, v0 # e0 : + ret # .. e1 : + + END(strchr) + +weak_alias (strchr, index) diff --git a/sysdeps/alpha/strcpy.S b/sysdeps/alpha/strcpy.S new file mode 100644 index 0000000..2975181 --- /dev/null +++ b/sysdeps/alpha/strcpy.S @@ -0,0 +1,36 @@ +/* Copyright (C) 1996 Free Software Foundation, Inc. + Contributed by Richard Henderson (rth@tamu.edu) + +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 Library General Public License as +published by the Free Software Foundation; either version 2 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 +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +/* Copy a null-terminated string from SRC to DST. Return a pointer + to the null-terminator in the source. */ + +#include <sysdep.h> + + .text + +ENTRY(strcpy) + ldgp gp, 0(pv) + .prologue 1 + + mov a0, v0 # set up return value + jsr t9, __stxcpy # do the copy + ret + + END(strcpy) diff --git a/sysdeps/alpha/strncat.S b/sysdeps/alpha/strncat.S new file mode 100644 index 0000000..d502037 --- /dev/null +++ b/sysdeps/alpha/strncat.S @@ -0,0 +1,90 @@ +/* Copyright (C) 1996 Free Software Foundation, Inc. + Contributed by Richard Henderson (rth@tamu.edu) + +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 Library General Public License as +published by the Free Software Foundation; either version 2 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 +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +/* Append no more than COUNT characters from the null-terminated string SRC + to the null-terminated string DST. Always null-terminate the new DST. */ + +#include <sysdep.h> + + .text + +ENTRY(strncat) + ldgp gp, 0(pv) + .prologue 1 + + mov a0, v0 # set up return value + beq a2, $zerocount + + /* Find the end of the string. */ + + ldq_u t0, 0(a0) # load first quadword (a0 may be misaligned) + lda t1, -1(zero) + insqh t1, a0, t1 + andnot a0, 7, a0 + or t1, t0, t0 + cmpbge zero, t0, t1 # t1 <- bitmask: bit i == 1 <==> i-th byte == 0 + bne t1, $found + +$loop: ldq t0, 8(a0) + addq a0, 8, a0 # addr += 8 + cmpbge zero, t0, t1 + beq t1, $loop + +$found: negq t1, t2 # clear all but least set bit + and t1, t2, t1 + + and t1, 0xf0, t2 # binary search for that set bit + and t1, 0xcc, t3 + and t1, 0xaa, t4 + cmovne t2, 4, t2 + cmovne t3, 2, t3 + cmovne t4, 1, t4 + addq t2, t3, t2 + addq a0, t4, a0 + addq a0, t2, a0 + + /* Now do the append. */ + + jsr t9, __stxncpy + + /* Worry about the null termination. */ + + zapnot t0, t8, t1 # was last byte a null? + bne t1, 0f + ret + +0: and t10, 0x80, t1 + bne t1, 1f + + /* Here there are bytes left in the current word. Clear one. */ + addq t10, t10, t10 # end-of-count bit <<= 1 + zap t0, t10, t0 + stq_u t0, 0(a0) + ret + +1: /* Here we must read the next DST word and clear the first byte. */ + ldq_u t0, 8(a0) + zap t0, 1, t0 + stq_u t0, 8(a0) + +$zerocount: + ret + + END(strncat) diff --git a/sysdeps/alpha/strncpy.S b/sysdeps/alpha/strncpy.S new file mode 100644 index 0000000..e13769c --- /dev/null +++ b/sysdeps/alpha/strncpy.S @@ -0,0 +1,85 @@ +/* Copyright (C) 1996 Free Software Foundation, Inc. + Contributed by Richard Henderson (rth@tamu.edu) + +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 Library General Public License as +published by the Free Software Foundation; either version 2 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 +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +/* Copy no more than COUNT bytes of the null-terminated string from + SRC to DST. If SRC does not cover all of COUNT, the balance is + zeroed. */ + +#include <sysdep.h> + + .set noat + .set noreorder + + .text + +ENTRY(strncpy) + ldgp gp, 0(pv) + .prologue 1 + + mov a0, v0 # set return value now + beq a2, $zerocount + jsr t9, __stxncpy # do the work of the copy + + bne a2, $multiword # do we have full words left? + + .align 3 + subq t8, 1, t2 # e0 : guess not + subq t10, 1, t3 # .. e1 : + or t2, t8, t2 # e0 : clear the bits between the last + or t3, t10, t3 # .. e1 : written byte and the last byte in + andnot t3, t2, t3 # e0 : COUNT + zap t0, t3, t0 # e1 : + stq_u t0, 0(a0) # e0 : + ret # .. e1 : + +$multiword: + + subq t8, 1, t7 # e0 : clear the final bits in the prev + or t7, t8, t7 # e1 : word + zapnot t0, t7, t0 # e0 : + subq a2, 1, a2 # .. e1 : + stq_u t0, 0(a0) # e0 : + addq a0, 8, a0 # .. e1 : + + beq a2, 1f # e1 : + blbc a2, 0f # e1 : + + stq_u zero, 0(a0) # e0 : zero one word + subq a2, 1, a2 # .. e1 : + addq a0, 8, a0 # e0 : + beq a2, 1f # .. e1 : + +0: stq_u zero, 0(a0) # e0 : zero two words + subq a2, 2, a2 # .. e1 : + stq_u zero, 8(a0) # e0 : + addq a0, 16, a0 # .. e1 : + bne a2, 0b # e1 : + unop + +1: ldq_u t0, 0(a0) # e0 : clear the leading bits in the final + subq t10, 1, t7 # .. e1 : word + or t7, t10, t7 # e0 : + zap t0, t7, t0 # e1 (stall) + stq_u t0, 0(a0) # e0 : + +$zerocount: + ret # .. e1 : + + END(strncpy) diff --git a/sysdeps/alpha/strrchr.S b/sysdeps/alpha/strrchr.S new file mode 100644 index 0000000..464f754 --- /dev/null +++ b/sysdeps/alpha/strrchr.S @@ -0,0 +1,104 @@ +/* Copyright (C) 1996 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 Library General Public License as +published by the Free Software Foundation; either version 2 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 +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +/* Return the address of the last occurrance of a given character + within a null-terminated string, or null if it is not found. + + This is generally scheduled for the EV5 (got to look out for my own + interests :-), but with EV4 needs in mind. There are, in fact, fewer + stalls on the EV4 than there are on the EV5. +*/ + +#include <sysdep.h> + + .set noreorder + .set noat + +ENTRY(strrchr) + .prologue 0 + + zapnot a1, 1, a1 # e0 : zero extend our test character + mov zero, t6 # .. e1 : t6 is last match aligned addr + sll a1, 8, t5 # e0 : replicate our test character + mov zero, t7 # .. e1 : t7 is last match byte compare mask + or t5, a1, a1 # e0 : + ldq_u t0, 0(a0) # .. e1 : load first quadword + sll a1, 16, t5 # e0 : + andnot a0, 7, v0 # .. e1 : align source addr + or t5, a1, a1 # e0 : + lda t4, -1 # .. e1 : build garbage mask + sll a1, 32, t5 # e0 : + cmpbge zero, t0, t1 # .. e1 : bits set iff byte == zero + mskqh t4, a0, t4 # e0 : + or t5, a1, a1 # .. e1 : character replication complete + xor t0, a1, t2 # e0 : make bytes == c zero + cmpbge zero, t4, t4 # .. e1 : bits set iff byte is garbage + cmpbge zero, t2, t3 # e0 : bits set iff byte == c + andnot t1, t4, t1 # .. e1 : clear garbage from null test + andnot t3, t4, t3 # e0 : clear garbage from char test + bne t1, $eos # .. e1 : did we already hit the terminator? + + /* Character search main loop */ +$loop: + ldq t0, 8(v0) # e0 : load next quadword + cmovne t3, v0, t6 # .. e1 : save previous comparisons match + cmovne t3, t3, t7 # e0 : + addq v0, 8, v0 # .. e1 : + xor t0, a1, t2 # e0 : + cmpbge zero, t0, t1 # .. e1 : bits set iff byte == zero + cmpbge zero, t2, t3 # e0 : bits set iff byte == c + beq t1, $loop # .. e1 : if we havnt seen a null, loop + + /* Mask out character matches after terminator */ +$eos: + negq t1, t4 # e0 : isolate first null byte match + and t1, t4, t4 # e1 : + subq t4, 1, t5 # e0 : build a mask of the bytes upto... + or t4, t5, t4 # e1 : ... and including the null + + and t3, t4, t3 # e0 : mask out char matches after null + cmovne t3, t3, t7 # .. e1 : save it, if match found + cmovne t3, v0, t6 # e0 : + + /* Locate the address of the last matched character */ + + /* Retain the early exit for the ev4 -- the ev5 mispredict penalty + is 5 cycles -- the same as just falling through. */ + beq t7, $retnull # .. e1 : + + and t7, 0xf0, t2 # e0 : binary search for the high bit set + cmovne t2, t2, t7 # .. e1 (zdb) + cmovne t2, 4, t2 # e0 : + and t7, 0xcc, t1 # .. e1 : + cmovne t1, t1, t7 # e0 : + cmovne t1, 2, t1 # .. e1 : + and t7, 0xaa, t0 # e0 : + cmovne t0, 1, t0 # .. e1 (zdb) + addq t2, t1, t1 # e0 : + addq t6, t0, v0 # .. e1 : add our aligned base ptr to the mix + addq v0, t1, v0 # e0 : + ret # .. e1 : + +$retnull: + mov zero, v0 # e0 : + ret # .. e1 : + + END(strrchr) + +weak_alias (strrchr, rindex) diff --git a/sysdeps/alpha/stxcpy.S b/sysdeps/alpha/stxcpy.S new file mode 100644 index 0000000..e381b70 --- /dev/null +++ b/sysdeps/alpha/stxcpy.S @@ -0,0 +1,307 @@ +/* Copyright (C) 1996 Free Software Foundation, Inc. + Contributed by Richard Henderson (rth@tamu.edu) + +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 Library General Public License as +published by the Free Software Foundation; either version 2 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 +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +/* Copy a null-terminated string from SRC to DST. + + This is an internal routine used by strcpy, stpcpy, and strcat. + As such, it uses special linkage conventions to make implementation + of these public functions more efficient. + + On input: + t9 = return address + a0 = DST + a1 = SRC + + On output: + t8 = bitmask (with one bit set) indicating the last byte written + a0 = unaligned address of the last *word* written + + Furthermore, v0, a3-a5, t11, and t12 are untouched. +*/ + +/* This is generally scheduled for the EV5, but should still be pretty + good for the EV4 too. */ + +#include <sysdep.h> + + .set noat + .set noreorder + + .text + +/* There is a problem with either gdb (as of 4.16) or gas (as of 2.7) that + doesn't like putting the entry point for a procedure somewhere in the + middle of the procedure descriptor. Work around this by putting the + aligned copy in its own procedure descriptor */ + + .ent stxcpy_aligned + .align 3 +stxcpy_aligned: + .frame sp, 0, t9 + .prologue 0 + + /* On entry to this basic block: + t0 == the first destination word for masking back in + t1 == the first source word. */ + + /* Create the 1st output word and detect 0's in the 1st input word. */ + lda t2, -1 # e1 : build a mask against false zero + mskqh t2, a1, t2 # e0 : detection in the src word + mskqh t1, a1, t3 # e0 : + ornot t1, t2, t2 # .. e1 : + mskql t0, a1, t0 # e0 : assemble the first output word + cmpbge zero, t2, t7 # .. e1 : bits set iff null found + or t0, t3, t1 # e0 : + bne t7, $a_eos # .. e1 : + + /* On entry to this basic block: + t0 == the first destination word for masking back in + t1 == a source word not containing a null. */ + +$a_loop: + stq_u t1, 0(a0) # e0 : + addq a0, 8, a0 # .. e1 : + ldq_u t1, 0(a1) # e0 : + addq a1, 8, a1 # .. e1 : + cmpbge zero, t1, t7 # e0 (stall) + beq t7, $a_loop # .. e1 (zdb) + + /* Take care of the final (partial) word store. + On entry to this basic block we have: + t1 == the source word containing the null + t7 == the cmpbge mask that found it. */ +$a_eos: + negq t7, t6 # e0 : find low bit set + and t7, t6, t8 # e1 (stall) + + /* For the sake of the cache, don't read a destination word + if we're not going to need it. */ + and t8, 0x80, t6 # e0 : + bne t6, 1f # .. e1 (zdb) + + /* We're doing a partial word store and so need to combine + our source and original destination words. */ + ldq_u t0, 0(a0) # e0 : + subq t8, 1, t6 # .. e1 : + zapnot t1, t6, t1 # e0 : clear src bytes >= null + or t8, t6, t7 # .. e1 : + zap t0, t7, t0 # e0 : clear dst bytes <= null + or t0, t1, t1 # e1 : + +1: stq_u t1, 0(a0) # e0 : + ret (t9) # .. e1 : + + .end stxcpy_aligned + + .align 3 + .ent __stxcpy + .globl __stxcpy +__stxcpy: + .frame sp, 0, t9 + .prologue 0 + + /* Are source and destination co-aligned? */ + xor a0, a1, t0 # e0 : + unop # : + and t0, 7, t0 # e0 : + bne t0, $unaligned # .. e1 : + + /* We are co-aligned; take care of a partial first word. */ + ldq_u t1, 0(a1) # e0 : load first src word + and a0, 7, t0 # .. e1 : take care not to load a word ... + addq a1, 8, a1 # e0 : + beq t0, stxcpy_aligned # .. e1 : ... if we wont need it + ldq_u t0, 0(a0) # e0 : + br stxcpy_aligned # .. e1 : + + +/* The source and destination are not co-aligned. Align the destination + and cope. We have to be very careful about not reading too much and + causing a SEGV. */ + + .align 3 +$u_head: + /* We know just enough now to be able to assemble the first + full source word. We can still find a zero at the end of it + that prevents us from outputting the whole thing. + + On entry to this basic block: + t0 == the first dest word, for masking back in, if needed else 0 + t1 == the low bits of the first source word + t6 == bytemask that is -1 in dest word bytes */ + + ldq_u t2, 8(a1) # e0 : + addq a1, 8, a1 # .. e1 : + + extql t1, a1, t1 # e0 : + extqh t2, a1, t4 # e0 : + mskql t0, a0, t0 # e0 : + or t1, t4, t1 # .. e1 : + mskqh t1, a0, t1 # e0 : + or t0, t1, t1 # e1 : + + or t1, t6, t6 # e0 : + cmpbge zero, t6, t7 # .. e1 : + lda t6, -1 # e0 : for masking just below + bne t7, $u_final # .. e1 : + + mskql t6, a1, t6 # e0 : mask out the bits we have + or t6, t2, t2 # e1 : already extracted before + cmpbge zero, t2, t7 # e0 : testing eos + bne t7, $u_late_head_exit # .. e1 (zdb) + + /* Finally, we've got all the stupid leading edge cases taken care + of and we can set up to enter the main loop. */ + + stq_u t1, 0(a0) # e0 : store first output word + addq a0, 8, a0 # .. e1 : + extql t2, a1, t0 # e0 : position ho-bits of lo word + ldq_u t2, 8(a1) # .. e1 : read next high-order source word + addq a1, 8, a1 # e0 : + cmpbge zero, t2, t7 # .. e1 : + nop # e0 : + bne t7, $u_eos # .. e1 : + + /* Unaligned copy main loop. In order to avoid reading too much, + the loop is structured to detect zeros in aligned source words. + This has, unfortunately, effectively pulled half of a loop + iteration out into the head and half into the tail, but it does + prevent nastiness from accumulating in the very thing we want + to run as fast as possible. + + On entry to this basic block: + t0 == the shifted high-order bits from the previous source word + t2 == the unshifted current source word + + We further know that t2 does not contain a null terminator. */ + + .align 3 +$u_loop: + extqh t2, a1, t1 # e0 : extract high bits for current word + addq a1, 8, a1 # .. e1 : + extql t2, a1, t3 # e0 : extract low bits for next time + addq a0, 8, a0 # .. e1 : + or t0, t1, t1 # e0 : current dst word now complete + ldq_u t2, 0(a1) # .. e1 : load high word for next time + stq_u t1, -8(a0) # e0 : save the current word + mov t3, t0 # .. e1 : + cmpbge zero, t2, t7 # e0 : test new word for eos + beq t7, $u_loop # .. e1 : + + /* We've found a zero somewhere in the source word we just read. + If it resides in the lower half, we have one (probably partial) + word to write out, and if it resides in the upper half, we + have one full and one partial word left to write out. + + On entry to this basic block: + t0 == the shifted high-order bits from the previous source word + t2 == the unshifted current source word. */ +$u_eos: + extqh t2, a1, t1 # e0 : + or t0, t1, t1 # e1 : first (partial) source word complete + + cmpbge zero, t1, t7 # e0 : is the null in this first bit? + bne t7, $u_final # .. e1 (zdb) + +$u_late_head_exit: + stq_u t1, 0(a0) # e0 : the null was in the high-order bits + addq a0, 8, a0 # .. e1 : + extql t2, a1, t1 # e0 : + cmpbge zero, t1, t7 # .. e1 : + + /* Take care of a final (probably partial) result word. + On entry to this basic block: + t1 == assembled source word + t7 == cmpbge mask that found the null. */ +$u_final: + negq t7, t6 # e0 : isolate low bit set + and t6, t7, t8 # e1 : + + and t8, 0x80, t6 # e0 : avoid dest word load if we can + bne t6, 1f # .. e1 (zdb) + + ldq_u t0, 0(a0) # e0 : + subq t8, 1, t6 # .. e1 : + or t6, t8, t7 # e0 : + zapnot t1, t6, t1 # .. e1 : kill source bytes >= null + zap t0, t7, t0 # e0 : kill dest bytes <= null + or t0, t1, t1 # e1 : + +1: stq_u t1, 0(a0) # e0 : + ret (t9) # .. e1 : + + /* Unaligned copy entry point. */ + .align 3 +$unaligned: + + ldq_u t1, 0(a1) # e0 : load first source word + + and a0, 7, t4 # .. e1 : find dest misalignment + and a1, 7, t5 # e0 : find src misalignment + + /* Conditionally load the first destination word and a bytemask + with 0xff indicating that the destination byte is sacrosanct. */ + + mov zero, t0 # .. e1 : + mov zero, t6 # e0 : + beq t4, 1f # .. e1 : + ldq_u t0, 0(a0) # e0 : + lda t6, -1 # .. e1 : + mskql t6, a0, t6 # e0 : +1: + subq a1, t4, a1 # .. e1 : sub dest misalignment from src addr + + /* If source misalignment is larger than dest misalignment, we need + extra startup checks to avoid SEGV. */ + + cmplt t4, t5, t8 # e0 : + beq t8, $u_head # .. e1 (zdb) + + lda t2, -1 # e1 : mask out leading garbage in source + mskqh t2, t5, t2 # e0 : + nop # e0 : + ornot t1, t2, t3 # .. e1 : + cmpbge zero, t3, t7 # e0 : is there a zero? + beq t7, $u_head # .. e1 (zdb) + + /* At this point we've found a zero in the first partial word of + the source. We need to isolate the valid source data and mask + it into the original destination data. (Incidentally, we know + that we'll need at least one byte of that original dest word.) */ + + ldq_u t0, 0(a0) # e0 : + + negq t7, t6 # .. e1 : build bitmask of bytes <= zero + and t6, t7, t8 # e0 : + nop # .. e1 : + subq t8, 1, t6 # e0 : + or t6, t8, t7 # e1 : + + zapnot t2, t7, t2 # e0 : prepare source word; mirror changes + and t1, t2, t1 # e1 : to source validity mask + extql t2, a1, t2 # e0 : + extql t1, a1, t1 # e0 : + + andnot t0, t2, t0 # e0 : zero place for source to reside + or t0, t1, t1 # e1 : and put it there + stq_u t1, 0(a0) # e0 : + ret (t9) # .. e1 : + + .end __stxcpy diff --git a/sysdeps/alpha/stxncpy.S b/sysdeps/alpha/stxncpy.S new file mode 100644 index 0000000..8c5fcf6 --- /dev/null +++ b/sysdeps/alpha/stxncpy.S @@ -0,0 +1,350 @@ +/* Copyright (C) 1996 Free Software Foundation, Inc. + Contributed by Richard Henderson (rth@tamu.edu) + +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 Library General Public License as +published by the Free Software Foundation; either version 2 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 +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +/* Copy no more than COUNT bytes of the null-terminated string from + SRC to DST. + + This is an internal routine used by strncpy, stpncpy, and strncat. + As such, it uses special linkage conventions to make implementation + of these public functions more efficient. + + On input: + t9 = return address + a0 = DST + a1 = SRC + a2 = COUNT + + Furthermore, COUNT may not be zero. + + On output: + t0 = last word written + t8 = bitmask (with one bit set) indicating the last byte written + t10 = bitmask (with one bit set) indicating the byte position of + the end of the range specified by COUNT + a0 = unaligned address of the last *word* written + a2 = the number of full words left in COUNT + + Furthermore, v0, a3-a5, t11, and t12 are untouched. +*/ + + +/* This is generally scheduled for the EV5, but should still be pretty + good for the EV4 too. */ + +#include <sysdep.h> + + .set noat + .set noreorder + + .text + +/* There is a problem with either gdb (as of 4.16) or gas (as of 2.7) that + doesn't like putting the entry point for a procedure somewhere in the + middle of the procedure descriptor. Work around this by putting the + aligned copy in its own procedure descriptor */ + + .ent stxncpy_aligned + .align 3 +stxncpy_aligned: + .frame sp, 0, t9, 0 + .prologue 0 + + /* On entry to this basic block: + t0 == the first destination word for masking back in + t1 == the first source word. */ + + /* Create the 1st output word and detect 0's in the 1st input word. */ + lda t2, -1 # e1 : build a mask against false zero + mskqh t2, a1, t2 # e0 : detection in the src word + mskqh t1, a1, t3 # e0 : + ornot t1, t2, t2 # .. e1 : + mskql t0, a1, t0 # e0 : assemble the first output word + cmpbge zero, t2, t7 # .. e1 : bits set iff null found + or t0, t3, t0 # e0 : + beq a2, $a_eoc # .. e1 : + bne t7, $a_eos # .. e1 : + + /* On entry to this basic block: + t0 == a source word not containing a null. */ + +$a_loop: + stq_u t0, 0(a0) # e0 : + addq a0, 8, a0 # .. e1 : + ldq_u t0, 0(a1) # e0 : + addq a1, 8, a1 # .. e1 : + subq a2, 1, a2 # e0 : + cmpbge zero, t0, t7 # .. e1 (stall) + beq a2, $a_eoc # e1 : + beq t7, $a_loop # e1 : + + /* Take care of the final (partial) word store. At this point + the end-of-count bit is set in t7 iff it applies. + + On entry to this basic block we have: + t0 == the source word containing the null + t7 == the cmpbge mask that found it. */ + +$a_eos: + negq t7, t8 # e0 : find low bit set + and t7, t8, t8 # e1 (stall) + + /* For the sake of the cache, don't read a destination word + if we're not going to need it. */ + and t8, 0x80, t6 # e0 : + bne t6, 1f # .. e1 (zdb) + + /* We're doing a partial word store and so need to combine + our source and original destination words. */ + ldq_u t1, 0(a0) # e0 : + subq t8, 1, t6 # .. e1 : + or t8, t6, t7 # e0 : + unop # + zapnot t0, t7, t0 # e0 : clear src bytes > null + zap t1, t7, t1 # .. e1 : clear dst bytes <= null + or t0, t1, t0 # e1 : + +1: stq_u t0, 0(a0) # e0 : + ret (t9) # e1 : + + /* Add the end-of-count bit to the eos detection bitmask. */ +$a_eoc: + or t10, t7, t7 + br $a_eos + + .end stxncpy_aligned + + .align 3 + .ent __stxncpy + .globl __stxncpy +__stxncpy: + .frame sp, 0, t9, 0 + .prologue 0 + + /* Are source and destination co-aligned? */ + xor a0, a1, t1 # e0 : + and a0, 7, t0 # .. e1 : find dest misalignment + and t1, 7, t1 # e0 : + addq a2, t0, a2 # .. e1 : bias count by dest misalignment + subq a2, 1, a2 # e0 : + and a2, 7, t2 # e1 : + srl a2, 3, a2 # e0 : a2 = loop counter = (count - 1)/8 + addq zero, 1, t10 # .. e1 : + sll t10, t2, t10 # e0 : t10 = bitmask of last count byte + bne t1, $unaligned # .. e1 : + + /* We are co-aligned; take care of a partial first word. */ + + ldq_u t1, 0(a1) # e0 : load first src word + addq a1, 8, a1 # .. e1 : + + beq t0, stxncpy_aligned # avoid loading dest word if not needed + ldq_u t0, 0(a0) # e0 : + br stxncpy_aligned # .. e1 : + + +/* The source and destination are not co-aligned. Align the destination + and cope. We have to be very careful about not reading too much and + causing a SEGV. */ + + .align 3 +$u_head: + /* We know just enough now to be able to assemble the first + full source word. We can still find a zero at the end of it + that prevents us from outputting the whole thing. + + On entry to this basic block: + t0 == the first dest word, unmasked + t1 == the shifted low bits of the first source word + t6 == bytemask that is -1 in dest word bytes */ + + ldq_u t2, 8(a1) # e0 : load second src word + addq a1, 8, a1 # .. e1 : + mskql t0, a0, t0 # e0 : mask trailing garbage in dst + extqh t2, a1, t4 # e0 : + or t1, t4, t1 # e1 : first aligned src word complete + mskqh t1, a0, t1 # e0 : mask leading garbage in src + or t0, t1, t0 # e0 : first output word complete + or t0, t6, t6 # e1 : mask original data for zero test + cmpbge zero, t6, t7 # e0 : + beq a2, $u_eocfin # .. e1 : + bne t7, $u_final # e1 : + + lda t6, -1 # e1 : mask out the bits we have + mskql t6, a1, t6 # e0 : already seen + stq_u t0, 0(a0) # e0 : store first output word + or t6, t2, t2 # .. e1 : + cmpbge zero, t2, t7 # e0 : find nulls in second partial + addq a0, 8, a0 # .. e1 : + subq a2, 1, a2 # e0 : + bne t7, $u_late_head_exit # .. e1 : + + /* Finally, we've got all the stupid leading edge cases taken care + of and we can set up to enter the main loop. */ + + extql t2, a1, t1 # e0 : position hi-bits of lo word + ldq_u t2, 8(a1) # .. e1 : read next high-order source word + addq a1, 8, a1 # e0 : + cmpbge zero, t2, t7 # e1 (stall) + beq a2, $u_eoc # e1 : + bne t7, $u_eos # e1 : + + /* Unaligned copy main loop. In order to avoid reading too much, + the loop is structured to detect zeros in aligned source words. + This has, unfortunately, effectively pulled half of a loop + iteration out into the head and half into the tail, but it does + prevent nastiness from accumulating in the very thing we want + to run as fast as possible. + + On entry to this basic block: + t1 == the shifted high-order bits from the previous source word + t2 == the unshifted current source word + + We further know that t2 does not contain a null terminator. */ + + .align 3 +$u_loop: + extqh t2, a1, t0 # e0 : extract high bits for current word + addq a1, 8, a1 # .. e1 : + extql t2, a1, t3 # e0 : extract low bits for next time + addq a0, 8, a0 # .. e1 : + or t0, t1, t0 # e0 : current dst word now complete + ldq_u t2, 0(a1) # .. e1 : load high word for next time + stq_u t0, -8(a0) # e0 : save the current word + mov t3, t1 # .. e1 : + subq a2, 1, a2 # e0 : + cmpbge zero, t2, t7 # .. e1 : test new word for eos + beq a2, $u_eoc # e1 : + beq t7, $u_loop # e1 : + + /* We've found a zero somewhere in the source word we just read. + If it resides in the lower half, we have one (probably partial) + word to write out, and if it resides in the upper half, we + have one full and one partial word left to write out. + + On entry to this basic block: + t1 == the shifted high-order bits from the previous source word + t2 == the unshifted current source word. */ +$u_eos: + extqh t2, a1, t0 # e0 : + or t0, t1, t0 # e1 : first (partial) source word complete + + cmpbge zero, t0, t7 # e0 : is the null in this first bit? + bne t7, $u_final # .. e1 (zdb) + + stq_u t0, 0(a0) # e0 : the null was in the high-order bits + addq a0, 8, a0 # .. e1 : + subq a2, 1, a2 # e1 : + +$u_late_head_exit: + extql t2, a1, t0 # .. e0 : + cmpbge zero, t0, t7 # e0 : + or t7, t10, t6 # e1 : + cmoveq a2, t6, t7 # e0 : + nop # .. e1 : + + /* Take care of a final (probably partial) result word. + On entry to this basic block: + t0 == assembled source word + t7 == cmpbge mask that found the null. */ +$u_final: + negq t7, t6 # e0 : isolate low bit set + and t6, t7, t8 # e1 : + + and t8, 0x80, t6 # e0 : avoid dest word load if we can + bne t6, 1f # .. e1 (zdb) + + ldq_u t1, 0(a0) # e0 : + subq t8, 1, t6 # .. e1 : + or t6, t8, t7 # e0 : + zapnot t0, t7, t0 # .. e1 : kill source bytes > null + zap t1, t7, t1 # e0 : kill dest bytes <= null + or t0, t1, t0 # e1 : + +1: stq_u t0, 0(a0) # e0 : + ret (t9) # .. e1 : + +$u_eoc: # end-of-count + extqh t2, a1, t0 + or t0, t1, t0 + cmpbge zero, t0, t7 + +$u_eocfin: # end-of-count, final word + or t10, t7, t7 + br $u_final + + /* Unaligned copy entry point. */ + .align 3 +$unaligned: + + ldq_u t1, 0(a1) # e0 : load first source word + + and a0, 7, t4 # .. e1 : find dest misalignment + and a1, 7, t5 # e0 : find src misalignment + + /* Conditionally load the first destination word and a bytemask + with 0xff indicating that the destination byte is sacrosanct. */ + + mov zero, t0 # .. e1 : + mov zero, t6 # e0 : + beq t4, 1f # .. e1 : + ldq_u t0, 0(a0) # e0 : + lda t6, -1 # .. e1 : + mskql t6, a0, t6 # e0 : +1: + subq a1, t4, a1 # .. e1 : sub dest misalignment from src addr + + /* If source misalignment is larger than dest misalignment, we need + extra startup checks to avoid SEGV. */ + + cmplt t4, t5, t8 # e1 : + extql t1, a1, t1 # .. e0 : shift src into place + lda t2, -1 # e0 : for creating masks later + beq t8, $u_head # e1 : + + mskqh t2, t5, t2 # e0 : begin src byte validity mask + cmpbge zero, t1, t7 # .. e1 : is there a zero? + extql t2, a1, t2 # e0 : + or t7, t10, t6 # .. e1 : test for end-of-count too + cmpbge zero, t2, t3 # e0 : + cmoveq a2, t6, t7 # .. e1 : + andnot t7, t3, t7 # e0 : + beq t7, $u_head # .. e1 (zdb) + + /* At this point we've found a zero in the first partial word of + the source. We need to isolate the valid source data and mask + it into the original destination data. (Incidentally, we know + that we'll need at least one byte of that original dest word.) */ + + ldq_u t0, 0(a0) # e0 : + negq t7, t6 # .. e1 : build bitmask of bytes <= zero + mskqh t1, t4, t1 # e0 : + and t6, t7, t8 # .. e1 : + subq t8, 1, t6 # e0 : + or t6, t8, t7 # e1 : + + zapnot t2, t7, t2 # e0 : prepare source word; mirror changes + zapnot t1, t7, t1 # .. e1 : to source validity mask + + andnot t0, t2, t0 # e0 : zero place for source to reside + or t0, t1, t0 # e1 : and put it there + stq_u t0, 0(a0) # e0 : + ret (t9) # .. e1 : + + .end __stxncpy |