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author | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-15 19:41:42 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-15 19:41:42 -0700 |
commit | d5d42399bd7b66bd6b55363b311810504110c967 (patch) | |
tree | bd676b8b8f2c85cecbe3777d7bb8c9a95e4cde98 /arch/x86 | |
parent | 209b6c8fa72e8b726a0cd273a56aded55be22bfa (diff) | |
parent | 9599ec0471deae24044241e2173090d2cbc0e899 (diff) | |
download | linux-d5d42399bd7b66bd6b55363b311810504110c967.tar.gz linux-d5d42399bd7b66bd6b55363b311810504110c967.tar.bz2 linux-d5d42399bd7b66bd6b55363b311810504110c967.zip |
Merge branch 'x86-mem-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-mem-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86-64, mem: Convert memmove() to assembly file and fix return value bug
Diffstat (limited to 'arch/x86')
-rw-r--r-- | arch/x86/kernel/x8664_ksyms_64.c | 1 | ||||
-rw-r--r-- | arch/x86/lib/memmove_64.S | 197 | ||||
-rw-r--r-- | arch/x86/lib/memmove_64.c | 192 |
3 files changed, 198 insertions, 192 deletions
diff --git a/arch/x86/kernel/x8664_ksyms_64.c b/arch/x86/kernel/x8664_ksyms_64.c index 1b950d151e58..9796c2f3d074 100644 --- a/arch/x86/kernel/x8664_ksyms_64.c +++ b/arch/x86/kernel/x8664_ksyms_64.c @@ -52,6 +52,7 @@ extern void *__memcpy(void *, const void *, __kernel_size_t); EXPORT_SYMBOL(memset); EXPORT_SYMBOL(memcpy); EXPORT_SYMBOL(__memcpy); +EXPORT_SYMBOL(memmove); EXPORT_SYMBOL(empty_zero_page); #ifndef CONFIG_PARAVIRT diff --git a/arch/x86/lib/memmove_64.S b/arch/x86/lib/memmove_64.S new file mode 100644 index 000000000000..0ecb8433e5a8 --- /dev/null +++ b/arch/x86/lib/memmove_64.S @@ -0,0 +1,197 @@ +/* + * Normally compiler builtins are used, but sometimes the compiler calls out + * of line code. Based on asm-i386/string.h. + * + * This assembly file is re-written from memmove_64.c file. + * - Copyright 2011 Fenghua Yu <fenghua.yu@intel.com> + */ +#define _STRING_C +#include <linux/linkage.h> +#include <asm/dwarf2.h> + +#undef memmove + +/* + * Implement memmove(). This can handle overlap between src and dst. + * + * Input: + * rdi: dest + * rsi: src + * rdx: count + * + * Output: + * rax: dest + */ +ENTRY(memmove) + CFI_STARTPROC + /* Handle more 32bytes in loop */ + mov %rdi, %rax + cmp $0x20, %rdx + jb 1f + + /* Decide forward/backward copy mode */ + cmp %rdi, %rsi + jb 2f + + /* + * movsq instruction have many startup latency + * so we handle small size by general register. + */ + cmp $680, %rdx + jb 3f + /* + * movsq instruction is only good for aligned case. + */ + + cmpb %dil, %sil + je 4f +3: + sub $0x20, %rdx + /* + * We gobble 32byts forward in each loop. + */ +5: + sub $0x20, %rdx + movq 0*8(%rsi), %r11 + movq 1*8(%rsi), %r10 + movq 2*8(%rsi), %r9 + movq 3*8(%rsi), %r8 + leaq 4*8(%rsi), %rsi + + movq %r11, 0*8(%rdi) + movq %r10, 1*8(%rdi) + movq %r9, 2*8(%rdi) + movq %r8, 3*8(%rdi) + leaq 4*8(%rdi), %rdi + jae 5b + addq $0x20, %rdx + jmp 1f + /* + * Handle data forward by movsq. + */ + .p2align 4 +4: + movq %rdx, %rcx + movq -8(%rsi, %rdx), %r11 + lea -8(%rdi, %rdx), %r10 + shrq $3, %rcx + rep movsq + movq %r11, (%r10) + jmp 13f + /* + * Handle data backward by movsq. + */ + .p2align 4 +7: + movq %rdx, %rcx + movq (%rsi), %r11 + movq %rdi, %r10 + leaq -8(%rsi, %rdx), %rsi + leaq -8(%rdi, %rdx), %rdi + shrq $3, %rcx + std + rep movsq + cld + movq %r11, (%r10) + jmp 13f + + /* + * Start to prepare for backward copy. + */ + .p2align 4 +2: + cmp $680, %rdx + jb 6f + cmp %dil, %sil + je 7b +6: + /* + * Calculate copy position to tail. + */ + addq %rdx, %rsi + addq %rdx, %rdi + subq $0x20, %rdx + /* + * We gobble 32byts backward in each loop. + */ +8: + subq $0x20, %rdx + movq -1*8(%rsi), %r11 + movq -2*8(%rsi), %r10 + movq -3*8(%rsi), %r9 + movq -4*8(%rsi), %r8 + leaq -4*8(%rsi), %rsi + + movq %r11, -1*8(%rdi) + movq %r10, -2*8(%rdi) + movq %r9, -3*8(%rdi) + movq %r8, -4*8(%rdi) + leaq -4*8(%rdi), %rdi + jae 8b + /* + * Calculate copy position to head. + */ + addq $0x20, %rdx + subq %rdx, %rsi + subq %rdx, %rdi +1: + cmpq $16, %rdx + jb 9f + /* + * Move data from 16 bytes to 31 bytes. + */ + movq 0*8(%rsi), %r11 + movq 1*8(%rsi), %r10 + movq -2*8(%rsi, %rdx), %r9 + movq -1*8(%rsi, %rdx), %r8 + movq %r11, 0*8(%rdi) + movq %r10, 1*8(%rdi) + movq %r9, -2*8(%rdi, %rdx) + movq %r8, -1*8(%rdi, %rdx) + jmp 13f + .p2align 4 +9: + cmpq $8, %rdx + jb 10f + /* + * Move data from 8 bytes to 15 bytes. + */ + movq 0*8(%rsi), %r11 + movq -1*8(%rsi, %rdx), %r10 + movq %r11, 0*8(%rdi) + movq %r10, -1*8(%rdi, %rdx) + jmp 13f +10: + cmpq $4, %rdx + jb 11f + /* + * Move data from 4 bytes to 7 bytes. + */ + movl (%rsi), %r11d + movl -4(%rsi, %rdx), %r10d + movl %r11d, (%rdi) + movl %r10d, -4(%rdi, %rdx) + jmp 13f +11: + cmp $2, %rdx + jb 12f + /* + * Move data from 2 bytes to 3 bytes. + */ + movw (%rsi), %r11w + movw -2(%rsi, %rdx), %r10w + movw %r11w, (%rdi) + movw %r10w, -2(%rdi, %rdx) + jmp 13f +12: + cmp $1, %rdx + jb 13f + /* + * Move data for 1 byte. + */ + movb (%rsi), %r11b + movb %r11b, (%rdi) +13: + retq + CFI_ENDPROC +ENDPROC(memmove) diff --git a/arch/x86/lib/memmove_64.c b/arch/x86/lib/memmove_64.c deleted file mode 100644 index 6d0f0ec41b34..000000000000 --- a/arch/x86/lib/memmove_64.c +++ /dev/null @@ -1,192 +0,0 @@ -/* Normally compiler builtins are used, but sometimes the compiler calls out - of line code. Based on asm-i386/string.h. - */ -#define _STRING_C -#include <linux/string.h> -#include <linux/module.h> - -#undef memmove -void *memmove(void *dest, const void *src, size_t count) -{ - unsigned long d0,d1,d2,d3,d4,d5,d6,d7; - char *ret; - - __asm__ __volatile__( - /* Handle more 32bytes in loop */ - "mov %2, %3\n\t" - "cmp $0x20, %0\n\t" - "jb 1f\n\t" - - /* Decide forward/backward copy mode */ - "cmp %2, %1\n\t" - "jb 2f\n\t" - - /* - * movsq instruction have many startup latency - * so we handle small size by general register. - */ - "cmp $680, %0\n\t" - "jb 3f\n\t" - /* - * movsq instruction is only good for aligned case. - */ - "cmpb %%dil, %%sil\n\t" - "je 4f\n\t" - "3:\n\t" - "sub $0x20, %0\n\t" - /* - * We gobble 32byts forward in each loop. - */ - "5:\n\t" - "sub $0x20, %0\n\t" - "movq 0*8(%1), %4\n\t" - "movq 1*8(%1), %5\n\t" - "movq 2*8(%1), %6\n\t" - "movq 3*8(%1), %7\n\t" - "leaq 4*8(%1), %1\n\t" - - "movq %4, 0*8(%2)\n\t" - "movq %5, 1*8(%2)\n\t" - "movq %6, 2*8(%2)\n\t" - "movq %7, 3*8(%2)\n\t" - "leaq 4*8(%2), %2\n\t" - "jae 5b\n\t" - "addq $0x20, %0\n\t" - "jmp 1f\n\t" - /* - * Handle data forward by movsq. - */ - ".p2align 4\n\t" - "4:\n\t" - "movq %0, %8\n\t" - "movq -8(%1, %0), %4\n\t" - "lea -8(%2, %0), %5\n\t" - "shrq $3, %8\n\t" - "rep movsq\n\t" - "movq %4, (%5)\n\t" - "jmp 13f\n\t" - /* - * Handle data backward by movsq. - */ - ".p2align 4\n\t" - "7:\n\t" - "movq %0, %8\n\t" - "movq (%1), %4\n\t" - "movq %2, %5\n\t" - "leaq -8(%1, %0), %1\n\t" - "leaq -8(%2, %0), %2\n\t" - "shrq $3, %8\n\t" - "std\n\t" - "rep movsq\n\t" - "cld\n\t" - "movq %4, (%5)\n\t" - "jmp 13f\n\t" - - /* - * Start to prepare for backward copy. - */ - ".p2align 4\n\t" - "2:\n\t" - "cmp $680, %0\n\t" - "jb 6f \n\t" - "cmp %%dil, %%sil\n\t" - "je 7b \n\t" - "6:\n\t" - /* - * Calculate copy position to tail. - */ - "addq %0, %1\n\t" - "addq %0, %2\n\t" - "subq $0x20, %0\n\t" - /* - * We gobble 32byts backward in each loop. - */ - "8:\n\t" - "subq $0x20, %0\n\t" - "movq -1*8(%1), %4\n\t" - "movq -2*8(%1), %5\n\t" - "movq -3*8(%1), %6\n\t" - "movq -4*8(%1), %7\n\t" - "leaq -4*8(%1), %1\n\t" - - "movq %4, -1*8(%2)\n\t" - "movq %5, -2*8(%2)\n\t" - "movq %6, -3*8(%2)\n\t" - "movq %7, -4*8(%2)\n\t" - "leaq -4*8(%2), %2\n\t" - "jae 8b\n\t" - /* - * Calculate copy position to head. - */ - "addq $0x20, %0\n\t" - "subq %0, %1\n\t" - "subq %0, %2\n\t" - "1:\n\t" - "cmpq $16, %0\n\t" - "jb 9f\n\t" - /* - * Move data from 16 bytes to 31 bytes. - */ - "movq 0*8(%1), %4\n\t" - "movq 1*8(%1), %5\n\t" - "movq -2*8(%1, %0), %6\n\t" - "movq -1*8(%1, %0), %7\n\t" - "movq %4, 0*8(%2)\n\t" - "movq %5, 1*8(%2)\n\t" - "movq %6, -2*8(%2, %0)\n\t" - "movq %7, -1*8(%2, %0)\n\t" - "jmp 13f\n\t" - ".p2align 4\n\t" - "9:\n\t" - "cmpq $8, %0\n\t" - "jb 10f\n\t" - /* - * Move data from 8 bytes to 15 bytes. - */ - "movq 0*8(%1), %4\n\t" - "movq -1*8(%1, %0), %5\n\t" - "movq %4, 0*8(%2)\n\t" - "movq %5, -1*8(%2, %0)\n\t" - "jmp 13f\n\t" - "10:\n\t" - "cmpq $4, %0\n\t" - "jb 11f\n\t" - /* - * Move data from 4 bytes to 7 bytes. - */ - "movl (%1), %4d\n\t" - "movl -4(%1, %0), %5d\n\t" - "movl %4d, (%2)\n\t" - "movl %5d, -4(%2, %0)\n\t" - "jmp 13f\n\t" - "11:\n\t" - "cmp $2, %0\n\t" - "jb 12f\n\t" - /* - * Move data from 2 bytes to 3 bytes. - */ - "movw (%1), %4w\n\t" - "movw -2(%1, %0), %5w\n\t" - "movw %4w, (%2)\n\t" - "movw %5w, -2(%2, %0)\n\t" - "jmp 13f\n\t" - "12:\n\t" - "cmp $1, %0\n\t" - "jb 13f\n\t" - /* - * Move data for 1 byte. - */ - "movb (%1), %4b\n\t" - "movb %4b, (%2)\n\t" - "13:\n\t" - : "=&d" (d0), "=&S" (d1), "=&D" (d2), "=&a" (ret) , - "=r"(d3), "=r"(d4), "=r"(d5), "=r"(d6), "=&c" (d7) - :"0" (count), - "1" (src), - "2" (dest) - :"memory"); - - return ret; - -} -EXPORT_SYMBOL(memmove); |