diff --git a/libc/arch-x86/string/sse2-wcschr-atom.S b/libc/arch-x86/string/sse2-wcschr-atom.S
new file mode 100644
index 0000000..729302b
--- /dev/null
+++ b/libc/arch-x86/string/sse2-wcschr-atom.S
@@ -0,0 +1,267 @@
+/*
+Copyright (c) 2011 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.
+*/
+
+#ifndef L
+# define L(label)	.L##label
+#endif
+
+#ifndef cfi_startproc
+# define cfi_startproc	.cfi_startproc
+#endif
+
+#ifndef cfi_endproc
+# define cfi_endproc	.cfi_endproc
+#endif
+
+#ifndef cfi_rel_offset
+# define cfi_rel_offset(reg, off)	.cfi_rel_offset reg, off
+#endif
+
+#ifndef cfi_restore
+# define cfi_restore(reg)	.cfi_restore reg
+#endif
+
+#ifndef cfi_adjust_cfa_offset
+# define cfi_adjust_cfa_offset(off)	.cfi_adjust_cfa_offset off
+#endif
+
+#ifndef ENTRY
+# define ENTRY(name)	\
+	.type name,  @function;	\
+	.globl name;	\
+	.p2align 4;	\
+name:	\
+	cfi_startproc
+#endif
+
+#ifndef END
+# define END(name)	\
+	cfi_endproc;	\
+	.size name,	.-name
+#endif
+
+#define CFI_PUSH(REG)	\
+	cfi_adjust_cfa_offset (4);	\
+	cfi_rel_offset (REG, 0)
+
+#define CFI_POP(REG)	\
+	cfi_adjust_cfa_offset (-4);	\
+	cfi_restore (REG)
+
+#define PUSH(REG)	pushl REG; CFI_PUSH (REG)
+#define POP(REG)	popl REG; CFI_POP (REG)
+
+#define PARMS	4
+
+
+#define STR1  PARMS
+#define STR2  STR1+4
+
+	.text
+ENTRY (wcschr)
+
+	mov	STR1(%esp), %ecx
+	movd	STR2(%esp), %xmm1
+
+	mov	%ecx, %eax
+	punpckldq %xmm1, %xmm1
+	pxor	%xmm2, %xmm2
+	punpckldq %xmm1, %xmm1
+
+	and	$63, %eax
+	cmp	$48, %eax
+	ja	L(cross_cache)
+
+	movdqu	(%ecx), %xmm0
+	pcmpeqd	%xmm0, %xmm2
+	pcmpeqd	%xmm1, %xmm0
+	pmovmskb %xmm2, %edx
+	pmovmskb %xmm0, %eax
+	or	%eax, %edx
+	jnz	L(matches)
+	and	$-16, %ecx
+	jmp	L(loop)
+
+	.p2align 4
+L(cross_cache):
+	PUSH	(%edi)
+	mov	%ecx, %edi
+	mov	%eax, %ecx
+	and	$-16, %edi
+	and	$15, %ecx
+	movdqa	(%edi), %xmm0
+	pcmpeqd	%xmm0, %xmm2
+	pcmpeqd	%xmm1, %xmm0
+	pmovmskb %xmm2, %edx
+	pmovmskb %xmm0, %eax
+
+	sarl	%cl, %edx
+	sarl	%cl, %eax
+	test	%eax, %eax
+	jz	L(unaligned_no_match)
+
+	add	%edi, %ecx
+	POP	(%edi)
+
+	test	%edx, %edx
+	jz	L(match_case1)
+	test	%al, %al
+	jz	L(match_higth_case2)
+	test	$15, %al
+	jnz	L(match_case2_4)
+	test	$15, %dl
+	jnz	L(return_null)
+	lea	4(%ecx), %eax
+	ret
+
+	CFI_PUSH (%edi)
+
+	.p2align 4
+L(unaligned_no_match):
+	mov	%edi, %ecx
+	POP	(%edi)
+
+	test	%edx, %edx
+	jnz	L(return_null)
+
+	pxor	%xmm2, %xmm2
+
+/* Loop start on aligned string.  */
+	.p2align 4
+L(loop):
+	add	$16, %ecx
+	movdqa	(%ecx), %xmm0
+	pcmpeqd	%xmm0, %xmm2
+	pcmpeqd	%xmm1, %xmm0
+	pmovmskb %xmm2, %edx
+	pmovmskb %xmm0, %eax
+	or	%eax, %edx
+	jnz	L(matches)
+	add	$16, %ecx
+
+	movdqa	(%ecx), %xmm0
+	pcmpeqd	%xmm0, %xmm2
+	pcmpeqd	%xmm1, %xmm0
+	pmovmskb %xmm2, %edx
+	pmovmskb %xmm0, %eax
+	or	%eax, %edx
+	jnz	L(matches)
+	add	$16, %ecx
+
+	movdqa	(%ecx), %xmm0
+	pcmpeqd	%xmm0, %xmm2
+	pcmpeqd	%xmm1, %xmm0
+	pmovmskb %xmm2, %edx
+	pmovmskb %xmm0, %eax
+	or	%eax, %edx
+	jnz	L(matches)
+	add	$16, %ecx
+
+	movdqa	(%ecx), %xmm0
+	pcmpeqd	%xmm0, %xmm2
+	pcmpeqd	%xmm1, %xmm0
+	pmovmskb %xmm2, %edx
+	pmovmskb %xmm0, %eax
+	or	%eax, %edx
+	jz	L(loop)
+
+	.p2align 4
+L(matches):
+	pmovmskb %xmm2, %edx
+	test	%eax, %eax
+	jz	L(return_null)
+	test	%edx, %edx
+	jz	L(match_case1)
+
+	.p2align 4
+L(match_case2):
+	test	%al, %al
+	jz	L(match_higth_case2)
+	test	$15, %al
+	jnz	L(match_case2_4)
+	test	$15, %dl
+	jnz	L(return_null)
+	lea	4(%ecx), %eax
+	ret
+
+	.p2align 4
+L(match_case2_4):
+	mov	%ecx, %eax
+	ret
+
+	.p2align 4
+L(match_higth_case2):
+	test	%dl, %dl
+	jnz	L(return_null)
+	test	$15, %ah
+	jnz	L(match_case2_12)
+	test	$15, %dh
+	jnz	L(return_null)
+	lea	12(%ecx), %eax
+	ret
+
+	.p2align 4
+L(match_case2_12):
+	lea	8(%ecx), %eax
+	ret
+
+	.p2align 4
+L(match_case1):
+	test	%al, %al
+	jz	L(match_higth_case1)
+
+	test	$0x01, %al
+	jnz	L(exit0)
+	lea	4(%ecx), %eax
+	ret
+
+	.p2align 4
+L(match_higth_case1):
+	test	$0x01, %ah
+	jnz	L(exit3)
+	lea	12(%ecx), %eax
+	ret
+
+	.p2align 4
+L(exit0):
+	mov	%ecx, %eax
+	ret
+
+	.p2align 4
+L(exit3):
+	lea	8(%ecx), %eax
+	ret
+
+	.p2align 4
+L(return_null):
+	xor	%eax, %eax
+	ret
+
+END (wcschr)