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Diffstat (limited to 'qemu/roms/u-boot/arch/x86/lib/string.c')
-rw-r--r--qemu/roms/u-boot/arch/x86/lib/string.c132
1 files changed, 132 insertions, 0 deletions
diff --git a/qemu/roms/u-boot/arch/x86/lib/string.c b/qemu/roms/u-boot/arch/x86/lib/string.c
new file mode 100644
index 000000000..a1656ccfe
--- /dev/null
+++ b/qemu/roms/u-boot/arch/x86/lib/string.c
@@ -0,0 +1,132 @@
+/*
+ * Copyright (C) 1991,1992,1993,1997,1998,2003, 2005 Free Software Foundation, Inc.
+ * This file is part of the GNU C Library.
+ * Copyright (c) 2011 The Chromium OS Authors.
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/* From glibc-2.14, sysdeps/i386/memset.c */
+
+#include <compiler.h>
+#include <asm/string.h>
+#include <linux/types.h>
+
+typedef uint32_t op_t;
+
+void *memset(void *dstpp, int c, size_t len)
+{
+ int d0;
+ unsigned long int dstp = (unsigned long int) dstpp;
+
+ /* This explicit register allocation improves code very much indeed. */
+ register op_t x asm("ax");
+
+ x = (unsigned char) c;
+
+ /* Clear the direction flag, so filling will move forward. */
+ asm volatile("cld");
+
+ /* This threshold value is optimal. */
+ if (len >= 12) {
+ /* Fill X with four copies of the char we want to fill with. */
+ x |= (x << 8);
+ x |= (x << 16);
+
+ /* Adjust LEN for the bytes handled in the first loop. */
+ len -= (-dstp) % sizeof(op_t);
+
+ /*
+ * There are at least some bytes to set. No need to test for
+ * LEN == 0 in this alignment loop.
+ */
+
+ /* Fill bytes until DSTP is aligned on a longword boundary. */
+ asm volatile(
+ "rep\n"
+ "stosb" /* %0, %2, %3 */ :
+ "=D" (dstp), "=c" (d0) :
+ "0" (dstp), "1" ((-dstp) % sizeof(op_t)), "a" (x) :
+ "memory");
+
+ /* Fill longwords. */
+ asm volatile(
+ "rep\n"
+ "stosl" /* %0, %2, %3 */ :
+ "=D" (dstp), "=c" (d0) :
+ "0" (dstp), "1" (len / sizeof(op_t)), "a" (x) :
+ "memory");
+ len %= sizeof(op_t);
+ }
+
+ /* Write the last few bytes. */
+ asm volatile(
+ "rep\n"
+ "stosb" /* %0, %2, %3 */ :
+ "=D" (dstp), "=c" (d0) :
+ "0" (dstp), "1" (len), "a" (x) :
+ "memory");
+
+ return dstpp;
+}
+
+#define OP_T_THRES 8
+#define OPSIZ (sizeof(op_t))
+
+#define BYTE_COPY_FWD(dst_bp, src_bp, nbytes) \
+do { \
+ int __d0; \
+ asm volatile( \
+ /* Clear the direction flag, so copying goes forward. */ \
+ "cld\n" \
+ /* Copy bytes. */ \
+ "rep\n" \
+ "movsb" : \
+ "=D" (dst_bp), "=S" (src_bp), "=c" (__d0) : \
+ "0" (dst_bp), "1" (src_bp), "2" (nbytes) : \
+ "memory"); \
+} while (0)
+
+#define WORD_COPY_FWD(dst_bp, src_bp, nbytes_left, nbytes) \
+do { \
+ int __d0; \
+ asm volatile( \
+ /* Clear the direction flag, so copying goes forward. */ \
+ "cld\n" \
+ /* Copy longwords. */ \
+ "rep\n" \
+ "movsl" : \
+ "=D" (dst_bp), "=S" (src_bp), "=c" (__d0) : \
+ "0" (dst_bp), "1" (src_bp), "2" ((nbytes) / 4) : \
+ "memory"); \
+ (nbytes_left) = (nbytes) % 4; \
+} while (0)
+
+void *memcpy(void *dstpp, const void *srcpp, size_t len)
+{
+ unsigned long int dstp = (long int)dstpp;
+ unsigned long int srcp = (long int)srcpp;
+
+ /* Copy from the beginning to the end. */
+
+ /* If there not too few bytes to copy, use word copy. */
+ if (len >= OP_T_THRES) {
+ /* Copy just a few bytes to make DSTP aligned. */
+ len -= (-dstp) % OPSIZ;
+ BYTE_COPY_FWD(dstp, srcp, (-dstp) % OPSIZ);
+
+ /* Copy from SRCP to DSTP taking advantage of the known
+ * alignment of DSTP. Number of bytes remaining is put
+ * in the third argument, i.e. in LEN. This number may
+ * vary from machine to machine.
+ */
+ WORD_COPY_FWD(dstp, srcp, len, len);
+
+ /* Fall out and copy the tail. */
+ }
+
+ /* There are just a few bytes to copy. Use byte memory operations. */
+ BYTE_COPY_FWD(dstp, srcp, len);
+
+ return dstpp;
+}