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authorZack Weinberg <zackw@panix.com>2017-06-08 15:39:03 -0400
committerZack Weinberg <zackw@panix.com>2017-06-08 15:39:03 -0400
commit5046dbb4a7eba5eccfd258f92f4735c9ffc8d069 (patch)
tree4470480d904b65cf14ca524f96f79eca818c3eaf /REORG.TODO/sysdeps/s390/multiarch/strncmp-vx.S
parent199fc19d3aaaf57944ef036e15904febe877fc93 (diff)
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Prepare for radical source tree reorganization. zack/build-layout-experiment
All top-level files and directories are moved into a temporary storage
directory, REORG.TODO, except for files that will certainly still
exist in their current form at top level when we're done (COPYING,
COPYING.LIB, LICENSES, NEWS, README), all old ChangeLog files (which
are moved to the new directory OldChangeLogs, instead), and the
generated file INSTALL (which is just deleted; in the new order, there
will be no generated files checked into version control).
Diffstat (limited to 'REORG.TODO/sysdeps/s390/multiarch/strncmp-vx.S')
-rw-r--r--REORG.TODO/sysdeps/s390/multiarch/strncmp-vx.S137
1 files changed, 137 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/s390/multiarch/strncmp-vx.S b/REORG.TODO/sysdeps/s390/multiarch/strncmp-vx.S
new file mode 100644
index 0000000000..ee35d2debf
--- /dev/null
+++ b/REORG.TODO/sysdeps/s390/multiarch/strncmp-vx.S
@@ -0,0 +1,137 @@
+/* Vector optimized 32/64 bit S/390 version of strncmp.
+   Copyright (C) 2015-2017 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
+
+/* int strncmp (const char *s1, const char *s2, size_t n)
+   Compare at most n characters of two strings.
+
+   Register usage:
+   -r0=tmp
+   -r1=tmp
+   -r2=s1
+   -r3=s2
+   -r4=n
+   -r5=current_len
+   -v16=part of s1
+   -v17=part of s2
+   -v18=index of unequal
+*/
+ENTRY(__strncmp_vx)
+	.machine "z13"
+	.machinemode "zarch_nohighgprs"
+
+# if !defined __s390x__
+	llgfr	%r4,%r4
+# endif /* !defined __s390x__ */
+
+	clgije	%r4,0,.Lend_equal /* Nothing to do if n == 0,  */
+	lghi	%r5,0		/* current_len = 0.  */
+
+.Lloop:
+	vlbb	%v16,0(%r5,%r2),6 /* Load s1 to block boundary.  */
+	vlbb	%v17,0(%r5,%r3),6 /* Load s2 to block boundary.  */
+	lcbb	%r0,0(%r5,%r2),6 /* Get loaded byte count of s1.  */
+	jo	.Llt16_1	/* Jump away if vr is not fully loaded.  */
+	lcbb	%r1,0(%r5,%r3),6 /* Get loaded byte count of s2.  */
+	jo	.Llt16_2	/* Jump away if vr is not fully loaded.  */
+	aghi	%r5,16		/* Both vrs are fully loaded.  */
+	clgrjhe	%r5,%r4,.Llastcmp /* If current_len >= n ->last compare.  */
+	vfenezbs %v18,%v16,%v17	/* Compare not equal with zero search.  */
+	jno	.Lfound
+
+	vlbb	%v16,0(%r5,%r2),6
+	vlbb	%v17,0(%r5,%r3),6
+	lcbb	%r0,0(%r5,%r2),6
+	jo	.Llt16_1
+	lcbb	%r1,0(%r5,%r3),6
+	jo	.Llt16_2
+	aghi	%r5,16
+	clgrjhe	%r5,%r4,.Llastcmp
+	vfenezbs %v18,%v16,%v17
+	jno	.Lfound
+
+	vlbb	%v16,0(%r5,%r2),6
+	vlbb	%v17,0(%r5,%r3),6
+	lcbb	%r0,0(%r5,%r2),6
+	jo	.Llt16_1
+	lcbb	%r1,0(%r5,%r3),6
+	jo	.Llt16_2
+	aghi	%r5,16
+	clgrjhe	%r5,%r4,.Llastcmp
+	vfenezbs %v18,%v16,%v17
+	jno	.Lfound
+
+	vlbb	%v16,0(%r5,%r2),6
+	vlbb	%v17,0(%r5,%r3),6
+	lcbb	%r0,0(%r5,%r2),6
+	jo	.Llt16_1
+	lcbb	%r1,0(%r5,%r3),6
+	jo	.Llt16_2
+	aghi	%r5,16
+	clgrjhe	%r5,%r4,.Llastcmp
+	vfenezbs %v18,%v16,%v17
+	jno	.Lfound
+	j	.Lloop
+
+.Llt16_1:
+	lcbb	%r1,0(%r5,%r3),6 /* Get loaded byte count ofs2.  */
+.Llt16_2:
+	clr	%r0,%r1		/* Compare logical.  */
+	locrh	%r0,%r1		/* Compute minimum of bytes loaded.  */
+	algfr	%r5,%r0		/* Add smallest loaded bytes to current_len.  */
+	clgrj	%r5,%r4,10,.Llastcmp /* If current_len >= n ->last compare.  */
+	vfenezbs %v18,%v16,%v17	/* Compare not equal with zero search.  */
+	vlgvb	%r1,%v18,7	/* Get not equal index or 16 if all equal.  */
+	clrjl	%r1,%r0,.Lfound /* Jump away if miscompare is within
+				    loaded bytes (index < loaded-bytes) */
+	j	.Lloop
+
+.Llastcmp:
+	/* Use comparision result only if located within first n characters.
+	   %r0: loaded byte count in vreg;
+	   %r5: current_len;
+	   %r4: n;
+	   (current_len - n): [0...16[
+	   First ignored match index: loaded bytes - (current_len-n): ]0...16]
+	*/
+	slgr	%r5,%r4		/* %r5 = current_len - n.  */
+	slr	%r0,%r5		/* %r0 = first ignored match index.  */
+	vfenezbs %v18,%v16,%v17	/* Compare not equal with zero search.  */
+	vlgvb	%r1,%v18,7	/* Get not equal index or 16 if all equal.  */
+	clrjl	%r1,%r0,.Lfound /* Jump away if miscompare is within
+				    loaded bytes and below n bytes.  */
+	j	.Lend_equal	/* Miscompare after n-bytes -> end equal.  */
+
+.Lfound:
+	/* Difference or end of string.  */
+	je	.Lend_equal
+	lghi	%r2,1
+	lghi	%r1,-1
+	locgrl	%r2,%r1
+	br	%r14
+.Lend_equal:
+	lghi	%r2,0
+	br	%r14
+END(__strncmp_vx)
+#endif /* HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc) */