optimized when asm

This commit is contained in:
Irmen de Jong 2019-07-09 21:59:50 +02:00
parent c1343a78f1
commit 16454f5560
2 changed files with 33 additions and 2 deletions

View File

@ -32,6 +32,15 @@ fun optimizeAssembly(lines: MutableList<String>): Int {
if(removeLines.isNotEmpty()) { if(removeLines.isNotEmpty()) {
for (i in removeLines.reversed()) for (i in removeLines.reversed())
lines.removeAt(i) lines.removeAt(i)
linesByFour = getLinesBy(lines, 4)
numberOfOptimizations++
}
removeLines = optimizeCmpSequence(linesByFour)
if(removeLines.isNotEmpty()) {
for (i in removeLines.reversed())
lines.removeAt(i)
linesByFour = getLinesBy(lines, 4)
numberOfOptimizations++ numberOfOptimizations++
} }
@ -40,6 +49,7 @@ fun optimizeAssembly(lines: MutableList<String>): Int {
if(removeLines.isNotEmpty()) { if(removeLines.isNotEmpty()) {
for (i in removeLines.reversed()) for (i in removeLines.reversed())
lines.removeAt(i) lines.removeAt(i)
linesByFourteen = getLinesBy(lines, 14)
numberOfOptimizations++ numberOfOptimizations++
} }
@ -48,6 +58,27 @@ fun optimizeAssembly(lines: MutableList<String>): Int {
return numberOfOptimizations return numberOfOptimizations
} }
fun optimizeCmpSequence(linesByFour: List<List<IndexedValue<String>>>): List<Int> {
// the when statement (on bytes) generates a sequence of:
// lda $ce01,x
// cmp #$20
// beq check_prog8_s72choice_32
// lda $ce01,x
// cmp #$21
// beq check_prog8_s73choice_33
// the repeated lda can be removed
val removeLines = mutableListOf<Int>()
for(lines in linesByFour) {
if(lines[0].value.trim()=="lda ${(ESTACK_LO+1).toHex()},x" &&
lines[1].value.trim().startsWith("cmp ") &&
lines[2].value.trim().startsWith("beq ") &&
lines[3].value.trim()=="lda ${(ESTACK_LO+1).toHex()},x") {
removeLines.add(lines[3].index) // remove the second lda
}
}
return removeLines
}
fun optimizeUselessStackByteWrites(linesByFour: List<List<IndexedValue<String>>>): List<Int> { fun optimizeUselessStackByteWrites(linesByFour: List<List<IndexedValue<String>>>): List<Int> {
// sta on stack, dex, inx, lda from stack -> eliminate this useless stack byte write // sta on stack, dex, inx, lda from stack -> eliminate this useless stack byte write
// this is a lot harder for word values because the instruction sequence varies. // this is a lot harder for word values because the instruction sequence varies.
@ -132,7 +163,7 @@ fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<String>>>):
} }
private fun getLinesBy(lines: MutableList<String>, windowSize: Int) = private fun getLinesBy(lines: MutableList<String>, windowSize: Int) =
// all lines (that aren't empty or comments) in sliding pairs of 2 // all lines (that aren't empty or comments) in sliding windows of certain size
lines.withIndex().filter { it.value.isNotBlank() && !it.value.trimStart().startsWith(';') }.windowed(windowSize, partialWindows = false) lines.withIndex().filter { it.value.isNotBlank() && !it.value.trimStart().startsWith(';') }.windowed(windowSize, partialWindows = false)
private fun optimizeStoreLoadSame(linesByFour: List<List<IndexedValue<String>>>): List<Int> { private fun optimizeStoreLoadSame(linesByFour: List<List<IndexedValue<String>>>): List<Int> {