34 lines
792 B
Go
34 lines
792 B
Go
package optimizer
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import "strings"
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// passSelfAssignment removes lda X; sta X pairs where the store immediately
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// follows the load and neither line is a branch target.
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func passSelfAssignment(lines []asmLine) []asmLine {
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var result []asmLine
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skipNext := false
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for i := 0; i < len(lines); i++ {
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if skipNext {
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skipNext = false
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continue
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}
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line := lines[i]
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// Check for lda X; sta X
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if line.isCode && line.opcode == "lda" && !isImmediate(line.operand) && i+1 < len(lines) {
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next := lines[i+1]
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if next.isCode && next.opcode == "sta" && next.operand == line.operand {
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if !strings.Contains(line.operand, "+") {
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skipNext = true // skip sta on next iteration
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continue // skip lda
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}
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}
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}
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result = append(result, line)
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}
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return result
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}
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