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
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
|
// Copyright 2021 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 vta
import (
"bytes"
"fmt"
"go/ast"
"go/parser"
"os"
"sort"
"strings"
"testing"
"golang.org/x/tools/go/callgraph"
"golang.org/x/tools/go/ssa/ssautil"
"golang.org/x/tools/go/loader"
"golang.org/x/tools/go/ssa"
)
// want extracts the contents of the first comment
// section starting with "WANT:\n". The returned
// content is split into lines without // prefix.
func want(f *ast.File) []string {
for _, c := range f.Comments {
text := strings.TrimSpace(c.Text())
if t := strings.TrimPrefix(text, "WANT:\n"); t != text {
return strings.Split(t, "\n")
}
}
return nil
}
// testProg returns an ssa representation of a program at
// `path`, assumed to define package "testdata," and the
// test want result as list of strings.
func testProg(path string, mode ssa.BuilderMode) (*ssa.Program, []string, error) {
content, err := os.ReadFile(path)
if err != nil {
return nil, nil, err
}
conf := loader.Config{
ParserMode: parser.ParseComments,
}
f, err := conf.ParseFile(path, content)
if err != nil {
return nil, nil, err
}
conf.CreateFromFiles("testdata", f)
iprog, err := conf.Load()
if err != nil {
return nil, nil, err
}
prog := ssautil.CreateProgram(iprog, mode)
// Set debug mode to exercise DebugRef instructions.
prog.Package(iprog.Created[0].Pkg).SetDebugMode(true)
prog.Build()
return prog, want(f), nil
}
func firstRegInstr(f *ssa.Function) ssa.Value {
for _, b := range f.Blocks {
for _, i := range b.Instrs {
if v, ok := i.(ssa.Value); ok {
return v
}
}
}
return nil
}
// funcName returns a name of the function `f`
// prefixed with the name of the receiver type.
func funcName(f *ssa.Function) string {
recv := f.Signature.Recv()
if recv == nil {
return f.Name()
}
tp := recv.Type().String()
return tp[strings.LastIndex(tp, ".")+1:] + "." + f.Name()
}
// callGraphStr stringifes `g` into a list of strings where
// each entry is of the form
//
// f: cs1 -> f1, f2, ...; ...; csw -> fx, fy, ...
//
// f is a function, cs1, ..., csw are call sites in f, and
// f1, f2, ..., fx, fy, ... are the resolved callees.
func callGraphStr(g *callgraph.Graph) []string {
var gs []string
for f, n := range g.Nodes {
c := make(map[string][]string)
for _, edge := range n.Out {
cs := edge.Site.String() // TODO(adonovan): handle Site=nil gracefully
c[cs] = append(c[cs], funcName(edge.Callee.Func))
}
var cs []string
for site, fs := range c {
sort.Strings(fs)
entry := fmt.Sprintf("%v -> %v", site, strings.Join(fs, ", "))
cs = append(cs, entry)
}
sort.Strings(cs)
entry := fmt.Sprintf("%v: %v", funcName(f), strings.Join(cs, "; "))
gs = append(gs, entry)
}
return gs
}
// Logs the functions of prog to t.
func logFns(t testing.TB, prog *ssa.Program) {
for fn := range ssautil.AllFunctions(prog) {
var buf bytes.Buffer
fn.WriteTo(&buf)
t.Log(buf.String())
}
}
|
