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-rw-r--r--lib/libc/ia64/string/bzero.S81
1 files changed, 81 insertions, 0 deletions
diff --git a/lib/libc/ia64/string/bzero.S b/lib/libc/ia64/string/bzero.S
new file mode 100644
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--- /dev/null
+++ b/lib/libc/ia64/string/bzero.S
@@ -0,0 +1,81 @@
+/*-
+ * Copyright (c) 2000 Doug Rabson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <machine/asm.h>
+__FBSDID("$FreeBSD$");
+
+ENTRY(bzero, 2)
+
+ cmp.le p6,p0=in1,r0 // bail if len <= 0
+(p6) br.ret.spnt.few rp
+ ;;
+ mov r14=ar.lc // save ar.lc
+
+ cmp.ltu p6,p0=17,in1 // check for small
+(p6) br.dptk.few 3f
+
+1: add r15=-1,in1 ;;
+ mov ar.lc=r15 ;;
+2: st1 [in0]=r0,1 // zero one byte
+ br.cloop.sptk.few 2b // loop
+
+ ;;
+ mov ar.lc=r14 // done
+ br.ret.sptk.few rp
+
+ // Zero up to 8byte alignment
+
+3: tbit.nz p6,p0=in0,0 ;;
+(p6) st1 [in0]=r0,1
+(p6) add in1=-1,in1 ;;
+
+ tbit.nz p6,p0=in0,1 ;;
+(p6) st2 [in0]=r0,2
+(p6) add in1=-2,in1 ;;
+
+ tbit.nz p6,p0=in0,2 ;;
+(p6) st4 [in0]=r0,4
+(p6) add in1=-4,in1
+
+ ;;
+ shr.u r15=in1,3 // word count
+ extr.u in1=in1,0,3 ;; // trailing bytes
+ cmp.eq p6,p0=r15,r0 // check for zero
+ cmp.ne p7,p0=in1,r0
+(p6) br.dpnt.few 1b // zero last bytes
+
+ add r15=-1,r15 ;;
+ mov ar.lc=r15 ;;
+4: st8 [in0]=r0,8
+ br.cloop.sptk.few 4b
+
+(p7) br.dpnt.few 1b // zero last bytes
+
+ ;;
+ mov ar.lc=r14 // done
+ br.ret.sptk.few rp
+
+END(bzero)
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