aboutsummaryrefslogtreecommitdiff
path: root/src/cmd/compile/internal/objw/objw.go
blob: ed5ad754d9b29f2e2e6c8cdd56655080c777e8f7 (plain)
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
85
// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package objw

import (
	"cmd/compile/internal/base"
	"cmd/compile/internal/bitvec"
	"cmd/compile/internal/types"
	"cmd/internal/obj"
)

// Uint8 writes an unsigned byte v into s at offset off,
// and returns the next unused offset (i.e., off+1).
func Uint8(s *obj.LSym, off int, v uint8) int {
	return UintN(s, off, uint64(v), 1)
}

func Uint16(s *obj.LSym, off int, v uint16) int {
	return UintN(s, off, uint64(v), 2)
}

func Uint32(s *obj.LSym, off int, v uint32) int {
	return UintN(s, off, uint64(v), 4)
}

func Uintptr(s *obj.LSym, off int, v uint64) int {
	return UintN(s, off, v, types.PtrSize)
}

// UintN writes an unsigned integer v of size wid bytes into s at offset off,
// and returns the next unused offset.
func UintN(s *obj.LSym, off int, v uint64, wid int) int {
	if off&(wid-1) != 0 {
		base.Fatalf("duintxxLSym: misaligned: v=%d wid=%d off=%d", v, wid, off)
	}
	s.WriteInt(base.Ctxt, int64(off), wid, int64(v))
	return off + wid
}

func SymPtr(s *obj.LSym, off int, x *obj.LSym, xoff int) int {
	off = int(types.Rnd(int64(off), int64(types.PtrSize)))
	s.WriteAddr(base.Ctxt, int64(off), types.PtrSize, x, int64(xoff))
	off += types.PtrSize
	return off
}

func SymPtrWeak(s *obj.LSym, off int, x *obj.LSym, xoff int) int {
	off = int(types.Rnd(int64(off), int64(types.PtrSize)))
	s.WriteWeakAddr(base.Ctxt, int64(off), types.PtrSize, x, int64(xoff))
	off += types.PtrSize
	return off
}

func SymPtrOff(s *obj.LSym, off int, x *obj.LSym) int {
	s.WriteOff(base.Ctxt, int64(off), x, 0)
	off += 4
	return off
}

func SymPtrWeakOff(s *obj.LSym, off int, x *obj.LSym) int {
	s.WriteWeakOff(base.Ctxt, int64(off), x, 0)
	off += 4
	return off
}

func Global(s *obj.LSym, width int32, flags int16) {
	if flags&obj.LOCAL != 0 {
		s.Set(obj.AttrLocal, true)
		flags &^= obj.LOCAL
	}
	base.Ctxt.Globl(s, int64(width), int(flags))
}

// Bitvec writes the contents of bv into s as sequence of bytes
// in little-endian order, and returns the next unused offset.
func BitVec(s *obj.LSym, off int, bv bitvec.BitVec) int {
	// Runtime reads the bitmaps as byte arrays. Oblige.
	for j := 0; int32(j) < bv.N; j += 8 {
		word := bv.B[j/32]
		off = Uint8(s, off, uint8(word>>(uint(j)%32)))
	}
	return off
}