mirror of https://github.com/tidwall/tile38.git
33 lines
845 B
Go
33 lines
845 B
Go
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package functions
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import (
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"honnef.co/go/tools/ir"
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)
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// IsStub reports whether a function is a stub. A function is
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// considered a stub if it has no instructions or if all it does is
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// return a constant value.
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func IsStub(fn *ir.Function) bool {
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for _, b := range fn.Blocks {
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for _, instr := range b.Instrs {
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switch instr.(type) {
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case *ir.Const:
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// const naturally has no side-effects
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case *ir.Panic:
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// panic is a stub if it only uses constants
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case *ir.Return:
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// return is a stub if it only uses constants
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case *ir.DebugRef:
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case *ir.Jump:
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// if there are no disallowed instructions, then we're
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// only jumping to the exit block (or possibly
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// somewhere else that's stubby?)
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default:
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// all other instructions are assumed to do actual work
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return false
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}
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}
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}
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return true
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}
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