api/vendor/honnef.co/go/tools/ssautil/ssautil.go

59 lines
985 B
Go

package ssautil
import (
"honnef.co/go/tools/ssa"
)
func Reachable(from, to *ssa.BasicBlock) bool {
if from == to {
return true
}
if from.Dominates(to) {
return true
}
found := false
Walk(from, func(b *ssa.BasicBlock) bool {
if b == to {
found = true
return false
}
return true
})
return found
}
func Walk(b *ssa.BasicBlock, fn func(*ssa.BasicBlock) bool) {
seen := map[*ssa.BasicBlock]bool{}
wl := []*ssa.BasicBlock{b}
for len(wl) > 0 {
b := wl[len(wl)-1]
wl = wl[:len(wl)-1]
if seen[b] {
continue
}
seen[b] = true
if !fn(b) {
continue
}
wl = append(wl, b.Succs...)
}
}
func Vararg(x *ssa.Slice) ([]ssa.Value, bool) {
var out []ssa.Value
slice, ok := x.X.(*ssa.Alloc)
if !ok || slice.Comment != "varargs" {
return nil, false
}
for _, ref := range *slice.Referrers() {
idx, ok := ref.(*ssa.IndexAddr)
if !ok {
continue
}
v := (*idx.Referrers())[0].(*ssa.Store).Val
out = append(out, v)
}
return out, true
}