1 files changed, 165 insertions, 0 deletions
diff --git a/libc/string/ia64/memcmp.S b/libc/string/ia64/memcmp.S
new file mode 100644
index 000000000..997dad9d4
--- /dev/null
+++ b/libc/string/ia64/memcmp.S
@@ -0,0 +1,165 @@
+/* Optimized version of the standard memcmp() function.
+   This file is part of the GNU C Library.
+   Copyright (C) 2000, 2001, 2004 Free Software Foundation, Inc.
+   Contributed by Dan Pop <Dan.Pop@cern.ch>.
+
+   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.  */
+
+/* Return: the result of the comparison
+
+   Inputs:
+        in0:    dest (aka s1)
+        in1:    src  (aka s2)
+        in2:    byte count
+
+   In this form, it assumes little endian mode.  For big endian mode, the
+   the two shifts in .l2 must be inverted:
+
+	shl   	tmp1[0] = r[1 + MEMLAT], sh1   // tmp1 = w0 << sh1
+	shr.u   tmp2[0] = r[0 + MEMLAT], sh2   // tmp2 = w1 >> sh2
+
+   and all the mux1 instructions should be replaced by plain mov's.  */
+
+#include <sysdep.h>
+#undef ret
+
+#define OP_T_THRES 	16
+#define OPSIZ 		8
+#define MEMLAT		2
+
+#define start		r15
+#define saved_pr	r17
+#define saved_lc	r18
+#define dest		r19
+#define src		r20
+#define len		r21
+#define asrc		r22
+#define tmp		r23
+#define value1		r24
+#define value2		r25
+#define sh2		r28
+#define	sh1		r29
+#define loopcnt		r30
+
+ENTRY(memcmp)
+	.prologue
+	alloc 	r2 = ar.pfs, 3, 37, 0, 40
+
+	.rotr	r[MEMLAT + 2], q[MEMLAT + 5], tmp1[4], tmp2[4], val[2]
+	.rotp	p[MEMLAT + 4 + 1]
+
+	mov	ret0 = r0		// by default return value = 0
+	.save pr, saved_pr
+	mov	saved_pr = pr		// save the predicate registers
+	.save ar.lc, saved_lc
+        mov 	saved_lc = ar.lc	// save the loop counter
+	.body
+	mov 	dest = in0		// dest
+	mov 	src = in1		// src
+	mov	len = in2		// len
+	sub	tmp = r0, in0		// tmp = -dest
+	;;
+	and	loopcnt = 7, tmp		// loopcnt = -dest % 8
+	cmp.ge	p6, p0 = OP_T_THRES, len	// is len <= OP_T_THRES
+(p6)	br.cond.spnt	.cmpfew			// compare byte by byte
+	;;
+	cmp.eq	p6, p0 = loopcnt, r0
+(p6)	br.cond.sptk .dest_aligned
+	sub	len = len, loopcnt	// len -= -dest % 8
+	adds	loopcnt = -1, loopcnt	// --loopcnt
+	;;
+	mov	ar.lc = loopcnt
+.l1:					// copy -dest % 8 bytes
+	ld1	value1 = [src], 1	// value = *src++
+	ld1	value2 = [dest], 1
+	;;
+	cmp.ne	p6, p0 = value1, value2
+(p6)	br.cond.spnt .done
+	br.cloop.dptk .l1
+.dest_aligned:
+	and	sh1 = 7, src 		// sh1 = src % 8
+	and	tmp = -8, len   	// tmp = len & -OPSIZ
+	and	asrc = -8, src		// asrc = src & -OPSIZ  -- align src
+	shr.u	loopcnt = len, 3	// loopcnt = len / 8
+	and	len = 7, len ;;		// len = len % 8
+	shl	sh1 = sh1, 3		// sh1 = 8 * (src % 8)
+	adds	loopcnt = -1, loopcnt	// --loopcnt
+	mov     pr.rot = 1 << 16 ;;	// set rotating predicates
+	sub	sh2 = 64, sh1		// sh2 = 64 - sh1
+	mov	ar.lc = loopcnt		// set LC
+	cmp.eq  p6, p0 = sh1, r0 	// is the src aligned?
+(p6)    br.cond.sptk .src_aligned
+	add	src = src, tmp		// src += len & -OPSIZ
+	mov	ar.ec = MEMLAT + 4 + 1 	// four more passes needed
+	ld8	r[1] = [asrc], 8 ;;	// r[1] = w0
+	.align	32
+
+// We enter this loop with p6 cleared by the above comparison
+
+.l2:
+(p[0])		ld8	r[0] = [asrc], 8		// r[0] = w1
+(p[0])		ld8	q[0] = [dest], 8
+(p[MEMLAT])	shr.u	tmp1[0] = r[1 + MEMLAT], sh1	// tmp1 = w0 >> sh1
+(p[MEMLAT])	shl	tmp2[0] = r[0 + MEMLAT], sh2  	// tmp2 = w1 << sh2
+(p[MEMLAT+4])	cmp.ne	p6, p0 = q[MEMLAT + 4], val[1]
+(p[MEMLAT+3])	or	val[0] = tmp1[3], tmp2[3] 	// val = tmp1 | tmp2
+(p6)		br.cond.spnt .l2exit
+		br.ctop.sptk    .l2
+		br.cond.sptk .cmpfew
+.l3exit:
+	mux1	value1 = r[MEMLAT], @rev
+	mux1	value2 = q[MEMLAT], @rev
+	cmp.ne	p6, p0 = r0, r0	;;	// clear p6
+.l2exit:
+(p6)	mux1	value1 = val[1], @rev
+(p6)	mux1	value2 = q[MEMLAT + 4], @rev ;;
+	cmp.ltu	p6, p7 = value2, value1 ;;
+(p6)	mov	ret0 = -1
+(p7)	mov	ret0 = 1
+	mov     pr = saved_pr, -1    	// restore the predicate registers
+	mov 	ar.lc = saved_lc	// restore the loop counter
+	br.ret.sptk.many b0
+.src_aligned:
+	cmp.ne	p6, p0 = r0, r0		// clear p6
+	mov     ar.ec = MEMLAT + 1 ;;	// set EC
+.l3:
+(p[0])		ld8	r[0] = [src], 8
+(p[0])		ld8	q[0] = [dest], 8
+(p[MEMLAT])	cmp.ne	p6, p0 = r[MEMLAT], q[MEMLAT]
+(p6)		br.cond.spnt .l3exit
+		br.ctop.dptk .l3 ;;
+.cmpfew:
+	cmp.eq	p6, p0 = len, r0	// is len == 0 ?
+	adds	len = -1, len		// --len;
+(p6)	br.cond.spnt	.restore_and_exit ;;
+	mov	ar.lc = len
+.l4:
+	ld1	value1 = [src], 1
+	ld1	value2 = [dest], 1
+	;;
+	cmp.ne	p6, p0 = value1, value2
+(p6)	br.cond.spnt	.done
+	br.cloop.dptk	.l4 ;;
+.done:
+(p6)	sub	ret0 = value2, value1	// don't execute it if falling thru
+.restore_and_exit:
+	mov     pr = saved_pr, -1    	// restore the predicate registers
+	mov 	ar.lc = saved_lc	// restore the loop counter
+	br.ret.sptk.many b0
+END(memcmp)
+
+weak_alias (memcmp, bcmp)
+libc_hidden_def (memcmp)