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+/* Copyright (C) 2000-2014 Free Software Foundation, Inc.
+ Contributed by Richard Henderson <rth@tamu.edu>, 1996.
+ EV67 optimized by Rick Gorton <rick.gorton@alpha-processor.com>.
+ 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 the address of a given character within a null-terminated
+ string, or null if it is not found. */
+
+#include <sysdep.h>
+
+ .arch ev6
+ .set noreorder
+ .set noat
+
+ENTRY(strchr)
+#ifdef PROF
+ ldgp gp, 0(pv)
+ lda AT, _mcount
+ jsr AT, (AT), _mcount
+ .prologue 1
+#else
+ .prologue 0
+#endif
+
+ ldq_u t0, 0(a0) # L : load first quadword Latency=3
+ and a1, 0xff, t3 # E : 00000000000000ch
+ insbl a1, 1, t5 # U : 000000000000ch00
+ insbl a1, 7, a2 # U : ch00000000000000
+
+ insbl t3, 6, a3 # U : 00ch000000000000
+ or t5, t3, a1 # E : 000000000000chch
+ andnot a0, 7, v0 # E : align our loop pointer
+ lda t4, -1 # E : build garbage mask
+
+ mskqh t4, a0, t4 # U : only want relevant part of first quad
+ or a2, a3, a2 # E : chch000000000000
+ inswl a1, 2, t5 # E : 00000000chch0000
+ inswl a1, 4, a3 # E : 0000chch00000000
+
+ or a1, a2, a1 # E : chch00000000chch
+ or a3, t5, t5 # E : 0000chchchch0000
+ cmpbge zero, t0, t2 # E : bits set iff byte == zero
+ cmpbge zero, t4, t4 # E : bits set iff byte is garbage
+
+ /* This quad is _very_ serialized. Lots of stalling happens */
+ or t5, a1, a1 # E : chchchchchchchch
+ xor t0, a1, t1 # E : make bytes == c zero
+ cmpbge zero, t1, t3 # E : bits set iff byte == c
+ or t2, t3, t0 # E : bits set iff char match or zero match
+
+ andnot t0, t4, t0 # E : clear garbage bits
+ cttz t0, a2 # U0 : speculative (in case we get a match)
+ nop # E :
+ bne t0, $found # U :
+
+ /*
+ * Yuk. This loop is going to stall like crazy waiting for the
+ * data to be loaded. Not much can be done about it unless it's
+ * unrolled multiple times, which is generally unsafe.
+ */
+$loop:
+ ldq t0, 8(v0) # L : Latency=3
+ addq v0, 8, v0 # E :
+ xor t0, a1, t1 # E :
+ cmpbge zero, t0, t2 # E : bits set iff byte == 0
+
+ cmpbge zero, t1, t3 # E : bits set iff byte == c
+ or t2, t3, t0 # E :
+ cttz t3, a2 # U0 : speculative (in case we get a match)
+ beq t0, $loop # U :
+
+$found:
+ negq t0, t1 # E : clear all but least set bit
+ and t0, t1, t0 # E :
+ and t0, t3, t1 # E : bit set iff byte was the char
+ addq v0, a2, v0 # E : Add in the bit number from above
+
+ cmoveq t1, $31, v0 # E : Two mapping slots, latency = 2
+ nop
+ nop
+ ret # L0 :
+
+ END(strchr)
+
+weak_alias (strchr, index)
+libc_hidden_builtin_def (strchr)