34 lines
698 B
Go
34 lines
698 B
Go
package asm
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import "git.akyoto.dev/cli/q/src/build/cpu"
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// unnecessary returns true if the register/register operation can be skipped.
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func (a *Assembler) unnecessary(mnemonic Mnemonic, left cpu.Register, right cpu.Register) bool {
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if mnemonic == MOVE && left == right {
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return true
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}
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if len(a.Instructions) == 0 {
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return false
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}
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last := a.Instructions[len(a.Instructions)-1]
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if mnemonic == MOVE && last.Mnemonic == MOVE {
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data, isRegReg := last.Data.(*RegisterRegister)
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if !isRegReg {
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return false
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}
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if data.Destination == left && data.Source == right {
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return true
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}
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if data.Destination == right && data.Source == left {
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return true
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}
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}
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return false
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}
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