Add 32-bit Silvermont-optimized string/memory functions.

Add following functions:
bcopy, memcpy, memmove, memset, bzero, memcmp, wmemcmp, strlen,
strcpy, strncpy, stpcpy, stpncpy.
Create new directories inside arch-x86 to specify architecture: atom,
silvermont and generic (non atom or silvermont architectures are treated like generic).
Due to introducing optimized versions of stpcpy and stpncpy,
c-implementations of these functions are moved from
common for architectures makefile to arm and mips specific makefiles.

Change-Id: I990f8061c3e9bca1f154119303da9e781c5d086e
Signed-off-by: Varvara Rainchik <varvara.rainchik@intel.com>
diff --git a/libc/arch-x86/silvermont/string/sse2-memcpy-slm.S b/libc/arch-x86/silvermont/string/sse2-memcpy-slm.S
new file mode 100644
index 0000000..1b305c7
--- /dev/null
+++ b/libc/arch-x86/silvermont/string/sse2-memcpy-slm.S
@@ -0,0 +1,308 @@
+/*
+Copyright (c) 2014, 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 "cache.h"
+
+#ifndef MEMCPY
+# define MEMCPY	memcpy
+#endif
+
+#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 DEST		PARMS
+#define SRC		DEST+4
+#define LEN		SRC+4
+
+#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		8		/* Preserve EBX.  */
+#define ENTRANCE	PUSH (%ebx);
+#define RETURN_END	POP (%ebx); ret
+#define RETURN		RETURN_END; CFI_PUSH (%ebx)
+
+	.section .text.sse2,"ax",@progbits
+ENTRY (MEMCPY)
+	ENTRANCE
+	movl	LEN(%esp), %ecx
+	movl	SRC(%esp), %eax
+	movl	DEST(%esp), %edx
+
+	cmp	%eax, %edx
+	je	L(return)
+
+	cmp	$16, %ecx
+	jbe	L(len_0_16_bytes)
+
+	cmp     $SHARED_CACHE_SIZE_HALF, %ecx
+	jae     L(large_page)
+
+	movdqu	(%eax), %xmm0
+	movdqu	-16(%eax, %ecx), %xmm1
+	cmpl    $32, %ecx
+	movdqu	%xmm0, (%edx)
+	movdqu	%xmm1, -16(%edx, %ecx)
+	jbe	L(return)
+
+	movdqu	16(%eax), %xmm0
+	movdqu	-32(%eax, %ecx), %xmm1
+	cmpl    $64, %ecx
+	movdqu	%xmm0, 16(%edx)
+	movdqu	%xmm1, -32(%edx, %ecx)
+	jbe	L(return)
+
+	movdqu	32(%eax), %xmm0
+	movdqu	48(%eax), %xmm1
+	movdqu	-48(%eax, %ecx), %xmm2
+	movdqu	-64(%eax, %ecx), %xmm3
+	cmpl    $128, %ecx
+	movdqu	%xmm0, 32(%edx)
+	movdqu	%xmm1, 48(%edx)
+	movdqu	%xmm2, -48(%edx, %ecx)
+	movdqu	%xmm3, -64(%edx, %ecx)
+	jbe	L(return)
+
+/* Now the main loop: we align the address of the destination.  */
+	leal	64(%edx), %ebx
+	andl	$-64, %ebx
+
+	addl	%edx, %ecx
+	andl	$-64, %ecx
+
+	subl	%edx, %eax
+
+/* We should stop two iterations before the termination
+	(in order not to misprefetch).  */
+	subl	$64, %ecx
+	cmpl	%ebx, %ecx
+	je	L(main_loop_just_one_iteration)
+
+	subl	$64, %ecx
+	cmpl	%ebx, %ecx
+	je	L(main_loop_last_two_iterations)
+
+
+	.p2align 4
+L(main_loop_cache):
+
+	prefetcht0 128(%ebx, %eax)
+
+	movdqu	(%ebx, %eax), %xmm0
+	movdqu	16(%ebx, %eax), %xmm1
+	movdqu	32(%ebx, %eax), %xmm2
+	movdqu	48(%ebx, %eax), %xmm3
+	movdqa	%xmm0, (%ebx)
+	movdqa	%xmm1, 16(%ebx)
+	movdqa	%xmm2, 32(%ebx)
+	movdqa	%xmm3, 48(%ebx)
+	lea	64(%ebx), %ebx
+	cmpl	%ebx, %ecx
+	jne	L(main_loop_cache)
+
+L(main_loop_last_two_iterations):
+	movdqu	(%ebx, %eax), %xmm0
+	movdqu	16(%ebx, %eax), %xmm1
+	movdqu	32(%ebx, %eax), %xmm2
+	movdqu	48(%ebx, %eax), %xmm3
+	movdqu	64(%ebx, %eax), %xmm4
+	movdqu	80(%ebx, %eax), %xmm5
+	movdqu	96(%ebx, %eax), %xmm6
+	movdqu	112(%ebx, %eax), %xmm7
+	movdqa	%xmm0, (%ebx)
+	movdqa	%xmm1, 16(%ebx)
+	movdqa	%xmm2, 32(%ebx)
+	movdqa	%xmm3, 48(%ebx)
+	movdqa	%xmm4, 64(%ebx)
+	movdqa	%xmm5, 80(%ebx)
+	movdqa	%xmm6, 96(%ebx)
+	movdqa	%xmm7, 112(%ebx)
+	jmp	L(return)
+
+L(main_loop_just_one_iteration):
+	movdqu	(%ebx, %eax), %xmm0
+	movdqu	16(%ebx, %eax), %xmm1
+	movdqu	32(%ebx, %eax), %xmm2
+	movdqu	48(%ebx, %eax), %xmm3
+	movdqa	%xmm0, (%ebx)
+	movdqa	%xmm1, 16(%ebx)
+	movdqa	%xmm2, 32(%ebx)
+	movdqa	%xmm3, 48(%ebx)
+	jmp	L(return)
+
+L(large_page):
+	movdqu	(%eax), %xmm0
+	movdqu	16(%eax), %xmm1
+	movdqu	32(%eax), %xmm2
+	movdqu	48(%eax), %xmm3
+	movdqu	-64(%eax, %ecx), %xmm4
+	movdqu	-48(%eax, %ecx), %xmm5
+	movdqu	-32(%eax, %ecx), %xmm6
+	movdqu	-16(%eax, %ecx), %xmm7
+	movdqu	%xmm0, (%edx)
+	movdqu	%xmm1, 16(%edx)
+	movdqu	%xmm2, 32(%edx)
+	movdqu	%xmm3, 48(%edx)
+	movdqu	%xmm4, -64(%edx, %ecx)
+	movdqu	%xmm5, -48(%edx, %ecx)
+	movdqu	%xmm6, -32(%edx, %ecx)
+	movdqu	%xmm7, -16(%edx, %ecx)
+
+	movdqu	64(%eax), %xmm0
+	movdqu	80(%eax), %xmm1
+	movdqu	96(%eax), %xmm2
+	movdqu	112(%eax), %xmm3
+	movdqu	-128(%eax, %ecx), %xmm4
+	movdqu	-112(%eax, %ecx), %xmm5
+	movdqu	-96(%eax, %ecx), %xmm6
+	movdqu	-80(%eax, %ecx), %xmm7
+	movdqu	%xmm0, 64(%edx)
+	movdqu	%xmm1, 80(%edx)
+	movdqu	%xmm2, 96(%edx)
+	movdqu	%xmm3, 112(%edx)
+	movdqu	%xmm4, -128(%edx, %ecx)
+	movdqu	%xmm5, -112(%edx, %ecx)
+	movdqu	%xmm6, -96(%edx, %ecx)
+	movdqu	%xmm7, -80(%edx, %ecx)
+
+/* Now the main loop with non temporal stores. We align
+	the address of the destination.  */
+	leal	128(%edx), %ebx
+	andl	$-128, %ebx
+
+	addl	%edx, %ecx
+	andl	$-128, %ecx
+
+	subl	%edx, %eax
+
+	.p2align 4
+L(main_loop_large_page):
+	movdqu	(%ebx, %eax), %xmm0
+	movdqu	16(%ebx, %eax), %xmm1
+	movdqu	32(%ebx, %eax), %xmm2
+	movdqu	48(%ebx, %eax), %xmm3
+	movdqu	64(%ebx, %eax), %xmm4
+	movdqu	80(%ebx, %eax), %xmm5
+	movdqu	96(%ebx, %eax), %xmm6
+	movdqu	112(%ebx, %eax), %xmm7
+	movntdq	%xmm0, (%ebx)
+	movntdq	%xmm1, 16(%ebx)
+	movntdq	%xmm2, 32(%ebx)
+	movntdq	%xmm3, 48(%ebx)
+	movntdq	%xmm4, 64(%ebx)
+	movntdq	%xmm5, 80(%ebx)
+	movntdq	%xmm6, 96(%ebx)
+	movntdq	%xmm7, 112(%ebx)
+	lea	128(%ebx), %ebx
+	cmpl	%ebx, %ecx
+	jne	L(main_loop_large_page)
+	sfence
+	jmp	L(return)
+
+L(len_0_16_bytes):
+	testb	$24, %cl
+	jne	L(len_9_16_bytes)
+	testb	$4, %cl
+	.p2align 4,,5
+	jne	L(len_5_8_bytes)
+	testl	%ecx, %ecx
+	.p2align 4,,2
+	je	L(return)
+	movzbl	(%eax), %ebx
+	testb	$2, %cl
+	movb	%bl, (%edx)
+	je	L(return)
+	movzwl	-2(%eax,%ecx), %ebx
+	movw	%bx, -2(%edx,%ecx)
+	jmp	L(return)
+
+L(len_9_16_bytes):
+	movq	(%eax), %xmm0
+	movq	-8(%eax, %ecx), %xmm1
+	movq	%xmm0, (%edx)
+	movq	%xmm1, -8(%edx, %ecx)
+	jmp	L(return)
+
+L(len_5_8_bytes):
+	movl	(%eax), %ebx
+	movl	%ebx, (%edx)
+	movl	-4(%eax,%ecx), %ebx
+	movl	%ebx, -4(%edx,%ecx)
+	jmp	L(return)
+
+L(return):
+	movl	%edx, %eax
+	RETURN
+
+END (MEMCPY)