1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
|
/* std.memblit : (dst : byte#, src : byte#, len : std.size -> void) */
.globl _std$memblit
.globl std$memblit
_std$memblit:
std$memblit:
cmpq %rdi,%rsi
movq %rdx,%rcx
jz .done
jg .fwdcpy
movq %rsi,%rax
subq %rdi,%rax
cmpq %rax,%rcx
jg .revcpy
.fwdcpy:
shrq $3,%rcx
rep movsq
movq %rdx,%rcx
andq $7,%rcx
rep movsb
jmp .done
.revcpy:
std
leaq -1(%rdx,%rsi),%rsi
leaq -1(%rdx,%rdi),%rdi
rep movsb
cld
.done:
ret
/* std.memfill : (dst : byte#, val : byte, len : std.size -> void) */
.globl _std$memfill
.globl std$memfill
_std$memfill:
std$memfill:
/* generate 8 bytes of fill */
movzbq %sil,%rbx
mov $0x101010101010101,%rax
imul %rbx,%rax
/* and fill */
movq %rdx,%rcx
shrq $3,%rcx
rep stosq
movq %rdx,%rcx
andq $7,%rcx
rep stosb
ret
/* std.memeq : (a : byte#, b : byte#, len : std.size -> bool) */
.globl _std$memeq
.globl std$memeq
_std$memeq:
std$memeq:
movq %rdx,%r8
andq $~0x7,%r8
jz .dotail
.nextquad:
movq (%rdi),%r9
movq (%rsi),%r10
xorq %r10,%r9
jnz .unequal
addq $8,%rsi
addq $8,%rdi
subq $8,%r8
jnz .nextquad
.dotail:
andq $0x7,%rdx
testq %rdx,%rdx
jz .equal
.nextbyte:
movzbl (%rdi),%r9d
movzbl (%rsi),%r10d
xorl %r10d,%r9d
jnz .unequal
addq $1,%rsi
addq $1,%rdi
subq $1,%rdx
jnz .nextbyte
.equal:
movq $1,%rax
ret
.unequal:
movq $0,%rax
ret
|
