435c0d9fc8
This PR switches the Nomad repository from using govendor to Go modules for managing dependencies. Aspects of the Nomad workflow remain pretty much the same. The usual Makefile targets should continue to work as they always did. The API submodule simply defers to the parent Nomad version on the repository, keeping the semantics of API versioning that currently exists.
55 lines
1 KiB
Go
55 lines
1 KiB
Go
package functions
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import "honnef.co/go/tools/ir"
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type Loop struct{ *ir.BlockSet }
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func FindLoops(fn *ir.Function) []Loop {
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if fn.Blocks == nil {
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return nil
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}
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tree := fn.DomPreorder()
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var sets []Loop
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for _, h := range tree {
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for _, n := range h.Preds {
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if !h.Dominates(n) {
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continue
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}
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// n is a back-edge to h
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// h is the loop header
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if n == h {
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set := Loop{ir.NewBlockSet(len(fn.Blocks))}
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set.Add(n)
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sets = append(sets, set)
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continue
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}
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set := Loop{ir.NewBlockSet(len(fn.Blocks))}
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set.Add(h)
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set.Add(n)
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for _, b := range allPredsBut(n, h, nil) {
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set.Add(b)
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}
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sets = append(sets, set)
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}
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}
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return sets
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}
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func allPredsBut(b, but *ir.BasicBlock, list []*ir.BasicBlock) []*ir.BasicBlock {
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outer:
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for _, pred := range b.Preds {
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if pred == but {
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continue
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}
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for _, p := range list {
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// TODO improve big-o complexity of this function
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if pred == p {
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continue outer
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}
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}
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list = append(list, pred)
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list = allPredsBut(pred, but, list)
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}
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return list
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}
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