1 files changed, 81 insertions, 0 deletions
diff --git a/src/isa-l/igzip/detect_repeated_char.asm b/src/isa-l/igzip/detect_repeated_char.asm
new file mode 100644
index 00000000..2f6c07a4
--- /dev/null
+++ b/src/isa-l/igzip/detect_repeated_char.asm
@@ -0,0 +1,81 @@
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;  Copyright(c) 2011-2016 Intel Corporation All rights reserved.
+;
+;  Redistribution and use in source and binary forms, with or without
+;  modification, are permitted provided that the following conditions
+;  are met:
+;    * Redistributions of source code must retain the above copyright
+;      notice, this list of conditions and the following disclaimer.
+;    * 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.
+;    * Neither the name of Intel Corporation nor the names of its
+;      contributors may be used to endorse or promote products derived
+;      from this software without specific prior written permission.
+;
+;  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT
+;  OWNER 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 "reg_sizes.asm"
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;;
+;; detect_repeated_char buf, size
+%ifidn __OUTPUT_FORMAT__, elf64
+ %define buf           rdi
+ %define size          rsi
+%elifidn __OUTPUT_FORMAT__, win64
+ %define buf           rcx
+ %define size          rdx
+%endif ; output formats
+
+%define tmp           r10
+
+global detect_repeated_char
+detect_repeated_char:
+
+;; replicate the 1st byte to 8 bytes
+	xor	tmp, tmp
+	xor	rax, rax
+
+	mov	al, [buf]
+	mov     ah, al
+	mov     tmp %+ w, ax
+	shl	tmp, 16
+	or	eax, tmp %+ d
+	mov	tmp %+ d, eax
+	shl	tmp, 32
+	or	rax, tmp
+
+;; detect the 8K input
+	lea	tmp, [buf + size]
+_loop:
+	cmp	rax, [buf]
+	jne	_fail
+	add	buf, 8
+	cmp	buf, tmp
+	jb	_loop
+	shr	rax, 56
+	jmp	_end
+
+_fail:
+	mov	rax, -1
+
+_end:
+	ret
+
+%undef buf
+%undef size
+%undef tmp