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