diff options
Diffstat (limited to 'tools/arch/x86/lib')
| -rw-r--r-- | tools/arch/x86/lib/memcpy_64.S | 297 | ||||
| -rw-r--r-- | tools/arch/x86/lib/memset_64.S | 139 |
2 files changed, 436 insertions, 0 deletions
diff --git a/tools/arch/x86/lib/memcpy_64.S b/tools/arch/x86/lib/memcpy_64.S new file mode 100644 index 000000000..3b24dc052 --- /dev/null +++ b/tools/arch/x86/lib/memcpy_64.S @@ -0,0 +1,297 @@ +/* Copyright 2002 Andi Kleen */ + +#include <linux/linkage.h> +#include <asm/errno.h> +#include <asm/cpufeatures.h> +#include <asm/mcsafe_test.h> +#include <asm/alternative-asm.h> +#include <asm/export.h> + +/* + * We build a jump to memcpy_orig by default which gets NOPped out on + * the majority of x86 CPUs which set REP_GOOD. In addition, CPUs which + * have the enhanced REP MOVSB/STOSB feature (ERMS), change those NOPs + * to a jmp to memcpy_erms which does the REP; MOVSB mem copy. + */ + +.weak memcpy + +/* + * memcpy - Copy a memory block. + * + * Input: + * rdi destination + * rsi source + * rdx count + * + * Output: + * rax original destination + */ +ENTRY(__memcpy) +ENTRY(memcpy) + ALTERNATIVE_2 "jmp memcpy_orig", "", X86_FEATURE_REP_GOOD, \ + "jmp memcpy_erms", X86_FEATURE_ERMS + + movq %rdi, %rax + movq %rdx, %rcx + shrq $3, %rcx + andl $7, %edx + rep movsq + movl %edx, %ecx + rep movsb + ret +ENDPROC(memcpy) +ENDPROC(__memcpy) +EXPORT_SYMBOL(memcpy) +EXPORT_SYMBOL(__memcpy) + +/* + * memcpy_erms() - enhanced fast string memcpy. This is faster and + * simpler than memcpy. Use memcpy_erms when possible. + */ +ENTRY(memcpy_erms) + movq %rdi, %rax + movq %rdx, %rcx + rep movsb + ret +ENDPROC(memcpy_erms) + +ENTRY(memcpy_orig) + movq %rdi, %rax + + cmpq $0x20, %rdx + jb .Lhandle_tail + + /* + * We check whether memory false dependence could occur, + * then jump to corresponding copy mode. + */ + cmp %dil, %sil + jl .Lcopy_backward + subq $0x20, %rdx +.Lcopy_forward_loop: + subq $0x20, %rdx + + /* + * Move in blocks of 4x8 bytes: + */ + movq 0*8(%rsi), %r8 + movq 1*8(%rsi), %r9 + movq 2*8(%rsi), %r10 + movq 3*8(%rsi), %r11 + leaq 4*8(%rsi), %rsi + + movq %r8, 0*8(%rdi) + movq %r9, 1*8(%rdi) + movq %r10, 2*8(%rdi) + movq %r11, 3*8(%rdi) + leaq 4*8(%rdi), %rdi + jae .Lcopy_forward_loop + addl $0x20, %edx + jmp .Lhandle_tail + +.Lcopy_backward: + /* + * Calculate copy position to tail. + */ + addq %rdx, %rsi + addq %rdx, %rdi + subq $0x20, %rdx + /* + * At most 3 ALU operations in one cycle, + * so append NOPS in the same 16 bytes trunk. + */ + .p2align 4 +.Lcopy_backward_loop: + subq $0x20, %rdx + movq -1*8(%rsi), %r8 + movq -2*8(%rsi), %r9 + movq -3*8(%rsi), %r10 + movq -4*8(%rsi), %r11 + leaq -4*8(%rsi), %rsi + movq %r8, -1*8(%rdi) + movq %r9, -2*8(%rdi) + movq %r10, -3*8(%rdi) + movq %r11, -4*8(%rdi) + leaq -4*8(%rdi), %rdi + jae .Lcopy_backward_loop + + /* + * Calculate copy position to head. + */ + addl $0x20, %edx + subq %rdx, %rsi + subq %rdx, %rdi +.Lhandle_tail: + cmpl $16, %edx + jb .Lless_16bytes + + /* + * Move data from 16 bytes to 31 bytes. + */ + movq 0*8(%rsi), %r8 + movq 1*8(%rsi), %r9 + movq -2*8(%rsi, %rdx), %r10 + movq -1*8(%rsi, %rdx), %r11 + movq %r8, 0*8(%rdi) + movq %r9, 1*8(%rdi) + movq %r10, -2*8(%rdi, %rdx) + movq %r11, -1*8(%rdi, %rdx) + retq + .p2align 4 +.Lless_16bytes: + cmpl $8, %edx + jb .Lless_8bytes + /* + * Move data from 8 bytes to 15 bytes. + */ + movq 0*8(%rsi), %r8 + movq -1*8(%rsi, %rdx), %r9 + movq %r8, 0*8(%rdi) + movq %r9, -1*8(%rdi, %rdx) + retq + .p2align 4 +.Lless_8bytes: + cmpl $4, %edx + jb .Lless_3bytes + + /* + * Move data from 4 bytes to 7 bytes. + */ + movl (%rsi), %ecx + movl -4(%rsi, %rdx), %r8d + movl %ecx, (%rdi) + movl %r8d, -4(%rdi, %rdx) + retq + .p2align 4 +.Lless_3bytes: + subl $1, %edx + jb .Lend + /* + * Move data from 1 bytes to 3 bytes. + */ + movzbl (%rsi), %ecx + jz .Lstore_1byte + movzbq 1(%rsi), %r8 + movzbq (%rsi, %rdx), %r9 + movb %r8b, 1(%rdi) + movb %r9b, (%rdi, %rdx) +.Lstore_1byte: + movb %cl, (%rdi) + +.Lend: + retq +ENDPROC(memcpy_orig) + +#ifndef CONFIG_UML + +MCSAFE_TEST_CTL + +/* + * __memcpy_mcsafe - memory copy with machine check exception handling + * Note that we only catch machine checks when reading the source addresses. + * Writes to target are posted and don't generate machine checks. + */ +ENTRY(__memcpy_mcsafe) + cmpl $8, %edx + /* Less than 8 bytes? Go to byte copy loop */ + jb .L_no_whole_words + + /* Check for bad alignment of source */ + testl $7, %esi + /* Already aligned */ + jz .L_8byte_aligned + + /* Copy one byte at a time until source is 8-byte aligned */ + movl %esi, %ecx + andl $7, %ecx + subl $8, %ecx + negl %ecx + subl %ecx, %edx +.L_read_leading_bytes: + movb (%rsi), %al + MCSAFE_TEST_SRC %rsi 1 .E_leading_bytes + MCSAFE_TEST_DST %rdi 1 .E_leading_bytes +.L_write_leading_bytes: + movb %al, (%rdi) + incq %rsi + incq %rdi + decl %ecx + jnz .L_read_leading_bytes + +.L_8byte_aligned: + movl %edx, %ecx + andl $7, %edx + shrl $3, %ecx + jz .L_no_whole_words + +.L_read_words: + movq (%rsi), %r8 + MCSAFE_TEST_SRC %rsi 8 .E_read_words + MCSAFE_TEST_DST %rdi 8 .E_write_words +.L_write_words: + movq %r8, (%rdi) + addq $8, %rsi + addq $8, %rdi + decl %ecx + jnz .L_read_words + + /* Any trailing bytes? */ +.L_no_whole_words: + andl %edx, %edx + jz .L_done_memcpy_trap + + /* Copy trailing bytes */ + movl %edx, %ecx +.L_read_trailing_bytes: + movb (%rsi), %al + MCSAFE_TEST_SRC %rsi 1 .E_trailing_bytes + MCSAFE_TEST_DST %rdi 1 .E_trailing_bytes +.L_write_trailing_bytes: + movb %al, (%rdi) + incq %rsi + incq %rdi + decl %ecx + jnz .L_read_trailing_bytes + + /* Copy successful. Return zero */ +.L_done_memcpy_trap: + xorl %eax, %eax + ret +ENDPROC(__memcpy_mcsafe) +EXPORT_SYMBOL_GPL(__memcpy_mcsafe) + + .section .fixup, "ax" + /* + * Return number of bytes not copied for any failure. Note that + * there is no "tail" handling since the source buffer is 8-byte + * aligned and poison is cacheline aligned. + */ +.E_read_words: + shll $3, %ecx +.E_leading_bytes: + addl %edx, %ecx +.E_trailing_bytes: + mov %ecx, %eax + ret + + /* + * For write fault handling, given the destination is unaligned, + * we handle faults on multi-byte writes with a byte-by-byte + * copy up to the write-protected page. + */ +.E_write_words: + shll $3, %ecx + addl %edx, %ecx + movl %ecx, %edx + jmp mcsafe_handle_tail + + .previous + + _ASM_EXTABLE_FAULT(.L_read_leading_bytes, .E_leading_bytes) + _ASM_EXTABLE_FAULT(.L_read_words, .E_read_words) + _ASM_EXTABLE_FAULT(.L_read_trailing_bytes, .E_trailing_bytes) + _ASM_EXTABLE(.L_write_leading_bytes, .E_leading_bytes) + _ASM_EXTABLE(.L_write_words, .E_write_words) + _ASM_EXTABLE(.L_write_trailing_bytes, .E_trailing_bytes) +#endif diff --git a/tools/arch/x86/lib/memset_64.S b/tools/arch/x86/lib/memset_64.S new file mode 100644 index 000000000..f8f3dc0a6 --- /dev/null +++ b/tools/arch/x86/lib/memset_64.S @@ -0,0 +1,139 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* Copyright 2002 Andi Kleen, SuSE Labs */ + +#include <linux/linkage.h> +#include <asm/cpufeatures.h> +#include <asm/alternative-asm.h> + +.weak memset + +/* + * ISO C memset - set a memory block to a byte value. This function uses fast + * string to get better performance than the original function. The code is + * simpler and shorter than the original function as well. + * + * rdi destination + * rsi value (char) + * rdx count (bytes) + * + * rax original destination + */ +ENTRY(memset) +ENTRY(__memset) + /* + * Some CPUs support enhanced REP MOVSB/STOSB feature. It is recommended + * to use it when possible. If not available, use fast string instructions. + * + * Otherwise, use original memset function. + */ + ALTERNATIVE_2 "jmp memset_orig", "", X86_FEATURE_REP_GOOD, \ + "jmp memset_erms", X86_FEATURE_ERMS + + movq %rdi,%r9 + movq %rdx,%rcx + andl $7,%edx + shrq $3,%rcx + /* expand byte value */ + movzbl %sil,%esi + movabs $0x0101010101010101,%rax + imulq %rsi,%rax + rep stosq + movl %edx,%ecx + rep stosb + movq %r9,%rax + ret +ENDPROC(memset) +ENDPROC(__memset) + +/* + * ISO C memset - set a memory block to a byte value. This function uses + * enhanced rep stosb to override the fast string function. + * The code is simpler and shorter than the fast string function as well. + * + * rdi destination + * rsi value (char) + * rdx count (bytes) + * + * rax original destination + */ +ENTRY(memset_erms) + movq %rdi,%r9 + movb %sil,%al + movq %rdx,%rcx + rep stosb + movq %r9,%rax + ret +ENDPROC(memset_erms) + +ENTRY(memset_orig) + movq %rdi,%r10 + + /* expand byte value */ + movzbl %sil,%ecx + movabs $0x0101010101010101,%rax + imulq %rcx,%rax + + /* align dst */ + movl %edi,%r9d + andl $7,%r9d + jnz .Lbad_alignment +.Lafter_bad_alignment: + + movq %rdx,%rcx + shrq $6,%rcx + jz .Lhandle_tail + + .p2align 4 +.Lloop_64: + decq %rcx + movq %rax,(%rdi) + movq %rax,8(%rdi) + movq %rax,16(%rdi) + movq %rax,24(%rdi) + movq %rax,32(%rdi) + movq %rax,40(%rdi) + movq %rax,48(%rdi) + movq %rax,56(%rdi) + leaq 64(%rdi),%rdi + jnz .Lloop_64 + + /* Handle tail in loops. The loops should be faster than hard + to predict jump tables. */ + .p2align 4 +.Lhandle_tail: + movl %edx,%ecx + andl $63&(~7),%ecx + jz .Lhandle_7 + shrl $3,%ecx + .p2align 4 +.Lloop_8: + decl %ecx + movq %rax,(%rdi) + leaq 8(%rdi),%rdi + jnz .Lloop_8 + +.Lhandle_7: + andl $7,%edx + jz .Lende + .p2align 4 +.Lloop_1: + decl %edx + movb %al,(%rdi) + leaq 1(%rdi),%rdi + jnz .Lloop_1 + +.Lende: + movq %r10,%rax + ret + +.Lbad_alignment: + cmpq $7,%rdx + jbe .Lhandle_7 + movq %rax,(%rdi) /* unaligned store */ + movq $8,%r8 + subq %r9,%r8 + addq %r8,%rdi + subq %r8,%rdx + jmp .Lafter_bad_alignment +.Lfinal: +ENDPROC(memset_orig) |