Apple-2-SW/prog8
1
0
Fork 0
mirror of https://github.com/irmen/prog8.git synced 2024-09-10 09:54:32 +00:00
Code Issues Projects Releases Wiki Activity

tiny tweak in asm optimizer

Browse Source
This commit is contained in:
Irmen de Jong 2022-02-08 02:19:50 +01:00
parent abda837d2f
commit 1635612430
1 changed files with 8 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
codeGenCpu6502/src/prog8/codegen/cpu6502/AsmOptimizer.kt
View File

@ -66,6 +66,7 @@ fun optimizeAssembly(lines: MutableList<String>, machine: IMachineDefinition, pr
private fun String.isBranch() = this.startsWith("b") private fun String.isBranch() = this.startsWith("b")
private fun String.isStoreReg() = this.startsWith("sta") || this.startsWith("sty") || this.startsWith("stx") private fun String.isStoreReg() = this.startsWith("sta") || this.startsWith("sty") || this.startsWith("stx")
private fun String.isStoreRegOrZero() = this.isStoreReg() || this.startsWith("stz")
private fun String.isLoadReg() = this.startsWith("lda") || this.startsWith("ldy") || this.startsWith("ldx") private fun String.isLoadReg() = this.startsWith("lda") || this.startsWith("ldy") || this.startsWith("ldx")
private class Modification(val lineIndex: Int, val remove: Boolean, val replacement: String?) private class Modification(val lineIndex: Int, val remove: Boolean, val replacement: String?)
@ -253,12 +254,13 @@ private fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<Stri
} }
} }
} }
/* /*
sta A1 sta A1
sty A2 sty A2 ; ... or stz
lda A1 ; can be removed if not followed by a branch instruction lda A1 ; can be removed if not followed by a branch instruction
*/ */
if(!overlappingMods && first.isStoreReg() && second.isStoreReg() if(!overlappingMods && first.isStoreReg() && second.isStoreRegOrZero()
&& third.isLoadReg() && !fourth.isBranch()) { && third.isLoadReg() && !fourth.isBranch()) {
val reg1 = first[2] val reg1 = first[2]
val reg3 = third[2] val reg3 = third[2]
@ -297,10 +299,10 @@ private fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<Stri
} }
/* /*
sta A sta A ; or stz double store, remove this first one
sta A sta A ; or stz
*/ */
if(!overlappingMods && first.isStoreReg() && second.isStoreReg()) { if(!overlappingMods && first.isStoreRegOrZero() && second.isStoreRegOrZero()) {
if(first[2]==second[2]) { if(first[2]==second[2]) {
val firstvalue = first.substring(4) val firstvalue = first.substring(4)
val secondvalue = second.substring(4) val secondvalue = second.substring(4)
@ -308,7 +310,7 @@ private fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<Stri
val address = getAddressArg(first, program) val address = getAddressArg(first, program)
if(address==null || !machine.isIOAddress(address)) { if(address==null || !machine.isIOAddress(address)) {
overlappingMods = true overlappingMods = true
mods.add(Modification(lines[1].index, true, null)) mods.add(Modification(lines[0].index, true, null))
} }
} }
} }