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-rw-r--r--ports/sysdeps/alpha/rawmemchr.S89
1 files changed, 89 insertions, 0 deletions
diff --git a/ports/sysdeps/alpha/rawmemchr.S b/ports/sysdeps/alpha/rawmemchr.S
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+/* Copyright (C) 2000, 2002 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/>.  */
+
+/* Return pointer to first occurrence of CH in STR.  */
+
+#include <sysdep.h>
+
+	.set noreorder
+	.set noat
+
+ENTRY(__rawmemchr)
+#ifdef PROF
+	ldgp	gp, 0(pv)
+	lda	AT, _mcount
+	jsr	AT, (AT), _mcount
+	.prologue 1
+#else
+	.prologue 0
+#endif
+
+	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    :
+	unop			#	:
+
+	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
+	unop			#	:
+
+	andnot	t3, t4, t0	# e0    : clear garbage bits
+	fnop			# .. fa :
+	unop			#	:
+	bne	t0, $found	# .. e1 (zdb)
+
+	.align 4
+$loop:
+	ldq	t0, 8(v0)	# e0    :
+	addq	v0, 8, v0	# .. e1 :
+	nop			# e0    :
+	xor	t0, a1, t1	# .. e1 (ev5 data stall)
+
+	cmpbge	zero, t1, t0	# e0	: bits set iff byte == c
+	beq	t0, $loop	# .. e1 (zdb)
+
+$found:
+	negq    t0, t1		# e0    : clear all but least set bit
+	and     t0, t1, t0	# e1 (stall)
+	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 :
+
+	END(__rawmemchr)
+
+libc_hidden_def (__rawmemchr)
+weak_alias (__rawmemchr, rawmemchr)