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Diffstat (limited to 'libc/string/sparc/sparc64/strlen.S')
-rw-r--r--libc/string/sparc/sparc64/strlen.S172
1 files changed, 172 insertions, 0 deletions
diff --git a/libc/string/sparc/sparc64/strlen.S b/libc/string/sparc/sparc64/strlen.S
new file mode 100644
index 000000000..5167ad5ba
--- /dev/null
+++ b/libc/string/sparc/sparc64/strlen.S
@@ -0,0 +1,172 @@
+/* Determine the length of a string. For SPARC v9.
+ Copyright (C) 1998, 1999, 2003 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Jan Vondrak <jvon4518@ss1000.ms.mff.cuni.cz> and
+ Jakub Jelinek <jj@ultra.linux.cz>.
+
+ 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 <asm/asi.h>
+
+ /* Normally, this uses
+ ((xword - 0x0101010101010101) & 0x8080808080808080) test
+ to find out if any byte in xword could be zero. This is fast, but
+ also gives false alarm for any byte in range 0x81-0xff. It does
+ not matter for correctness, as if this test tells us there could
+ be some zero byte, we check it byte by byte, but if bytes with
+ high bits set are common in the strings, then this will give poor
+ performance. You can #define EIGHTBIT_NOT_RARE and the algorithm
+ will use one tick slower, but more precise test
+ ((xword - 0x0101010101010101) & (~xword) & 0x8080808080808080),
+ which does not give any false alarms (but if some bits are set,
+ one cannot assume from it which bytes are zero and which are not).
+ It is yet to be measured, what is the correct default for glibc
+ in these days for an average user.
+ */
+
+ .text
+ .align 32
+ENTRY(strlen)
+ sethi %hi(0x01010101), %g1 /* IEU0 Group */
+ ldub [%o0], %o3 /* Load */
+ or %g1, %lo(0x01010101), %g1 /* IEU0 Group */
+ mov %o0, %o1 /* IEU1 */
+
+ sllx %g1, 32, %g4 /* IEU0 Group */
+ andcc %o0, 7, %g0 /* IEU1 */
+ or %g1, %g4, %g1 /* IEU0 Group */
+ brz,pn %o3, 13f /* CTI+IEU1 */
+
+ sllx %g1, 7, %g4 /* IEU0 Group */
+ bne,a,pn %icc, 15f /* CTI */
+ add %o0, 1, %o0 /* IEU1 */
+ /* %g1 = 0x0101010101010101 *
+ * %g4 = 0x8080808080808080 *
+ * %o0 = string pointer *
+ * %o1 = start of string */
+1: ldx [%o0], %o3 /* Load Group */
+
+ add %o0, 8, %o0 /* IEU1 */
+2: sub %o3, %g1, %o2 /* IEU0 Group */
+#ifdef EIGHTBIT_NOT_RARE
+ andn %o2, %o3, %o5 /* IEU0 Group */
+ ldxa [%o0] ASI_PNF, %o3 /* Load */
+ andcc %o5, %g4, %g0 /* IEU1 Group */
+#else
+ ldxa [%o0] ASI_PNF, %o3 /* Load */
+ andcc %o2, %g4, %g0 /* IEU1 Group */
+#endif
+
+ be,pt %xcc, 2b /* CTI */
+ add %o0, 8, %o0 /* IEU0 */
+ addcc %o2, %g1, %g5 /* IEU1 Group */
+#ifdef EIGHTBIT_NOT_RARE
+ srlx %o5, 32, %o5 /* IEU0 */
+
+3: andcc %o5, %g4, %g0 /* IEU1 Group */
+#else
+ srlx %o2, 32, %o2 /* IEU0 */
+
+3: andcc %o2, %g4, %g0 /* IEU1 Group */
+#endif
+ be,pn %xcc, 4f /* CTI */
+ srlx %g5, 56, %o2 /* IEU0 */
+ andcc %o2, 0xff, %g0 /* IEU1 Group */
+
+ be,pn %icc, 12f /* CTI */
+ srlx %g5, 48, %o2 /* IEU0 */
+ andcc %o2, 0xff, %g0 /* IEU1 Group */
+ be,pn %icc, 11f /* CTI */
+
+ srlx %g5, 40, %o2 /* IEU0 */
+ andcc %o2, 0xff, %g0 /* IEU1 Group */
+ be,pn %icc, 10f /* CTI */
+ srlx %g5, 32, %o2 /* IEU0 */
+
+ andcc %o2, 0xff, %g0 /* IEU1 Group */
+ be,pn %icc, 9f /* CTI */
+4: srlx %g5, 24, %o2 /* IEU0 */
+ andcc %o2, 0xff, %g0 /* IEU1 Group */
+
+ be,pn %icc, 8f /* CTI */
+ srlx %g5, 16, %o2 /* IEU0 */
+ andcc %o2, 0xff, %g0 /* IEU1 Group */
+ be,pn %icc, 7f /* CTI */
+
+ srlx %g5, 8, %o2 /* IEU0 */
+ andcc %o2, 0xff, %g0 /* IEU1 Group */
+ be,pn %icc, 6f /* CTI */
+ sub %o3, %g1, %o2 /* IEU0 */
+
+ andcc %g5, 0xff, %g0 /* IEU1 Group */
+ be,pn %icc, 5f /* CTI */
+ ldxa [%o0] ASI_PNF, %o3 /* Load */
+ andcc %o2, %g4, %g0 /* IEU1 Group */
+
+ be,pt %xcc, 2b /* CTI */
+ add %o0, 8, %o0 /* IEU0 */
+ addcc %o2, %g1, %g5 /* IEU1 Group */
+ ba,pt %xcc, 3b /* CTI */
+
+ srlx %o2, 32, %o2 /* IEU0 */
+5: add %o0, -9, %o0 /* IEU0 Group */
+ retl /* CTI+IEU1 Group */
+ sub %o0, %o1, %o0 /* IEU0 */
+
+6: add %o0, -10, %o0 /* IEU0 Group */
+ retl /* CTI+IEU1 Group */
+ sub %o0, %o1, %o0 /* IEU0 */
+7: add %o0, -11, %o0 /* IEU0 Group */
+
+ retl /* CTI+IEU1 Group */
+ sub %o0, %o1, %o0 /* IEU0 */
+8: add %o0, -12, %o0 /* IEU0 Group */
+ retl /* CTI+IEU1 Group */
+
+ sub %o0, %o1, %o0 /* IEU0 */
+9: add %o0, -13, %o0 /* IEU0 Group */
+ retl /* CTI+IEU1 Group */
+ sub %o0, %o1, %o0 /* IEU0 */
+
+10: add %o0, -14, %o0 /* IEU0 Group */
+ retl /* CTI+IEU1 Group */
+ sub %o0, %o1, %o0 /* IEU0 */
+11: add %o0, -15, %o0 /* IEU0 Group */
+
+ retl /* CTI+IEU1 Group */
+ sub %o0, %o1, %o0 /* IEU0 */
+12: add %o0, -16, %o0 /* IEU0 Group */
+ retl /* CTI+IEU1 Group */
+
+ sub %o0, %o1, %o0 /* IEU0 */
+13: retl /* CTI+IEU1 Group */
+ mov 0, %o0 /* IEU0 */
+ nop
+
+15: ldub [%o0], %o3 /* Load Group */
+16: andcc %o0, 7, %g0 /* IEU1 */
+ be,pn %icc, 1b /* CTI */
+ nop /* IEU0 Group */
+
+ add %o0, 1, %o0 /* IEU1 */
+ andcc %o3, 0xff, %g0 /* IEU1 Group */
+ bne,a,pt %icc, 16b /* CTI */
+ lduba [%o0] ASI_PNF, %o3 /* Load */
+
+ add %o0, -1, %o0 /* IEU0 Group */
+ retl /* CTI+IEU1 Group */
+ sub %o0, %o1, %o0 /* IEU0 */
+END(strlen)