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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)