Apple-2-SW/prog8
1
0
Fork 0
mirror of https://github.com/irmen/prog8.git synced 2026-04-22 08:16:49 +00:00
Code Issues Projects Releases Wiki Activity

optimized pointer access @(pointer - constantoffset)

Browse Source
This commit is contained in:
Irmen de Jong
2025-01-05 06:07:33 +01:00
parent 0ffebc25d0
commit 3b3616afda
3 changed files with 52 additions and 64 deletions
Download Patch File Download Diff File Expand all files Collapse all files
codeGenCpu6502/src/prog8/codegen/cpu6502/AsmGen.kt
+21 -25
View File
@@ -1322,34 +1322,19 @@ $repeatLabel""")
}
if(constOffset!=null) {
println("MEMWRITE POINTER - $constOffset ${addressExpr.position}") // TODO
/*
val pointervar = ptrAndIndex.first as? PtIdentifier
if(pointervar!=null && isZpVar(pointervar)) {
val saveA = evalBytevalueWillClobberA(ptrAndIndex.second)
if(saveA) out(" pha")
assignExpressionToRegister(ptrAndIndex.second, RegisterOrPair.Y)
if(saveA) out(" pla")
out(" sta (${asmSymbolName(pointervar)}),y")
val varname = asmSymbolName(pointervar)
out(" ldy #${256-constOffset} ; negative offset $constOffset")
out(" dec $varname+1 | sta ($varname),y | inc $varname+1") // temporarily make MSB 1 less
return true
} else {
// copy the pointer var to zp first
val saveA = evalBytevalueWillClobberA(ptrAndIndex.first) || evalBytevalueWillClobberA(ptrAndIndex.second)
if(saveA) out(" pha")
if(ptrAndIndex.second.isSimple()) {
assignExpressionToVariable(ptrAndIndex.first, "P8ZP_SCRATCH_W2", DataType.forDt(BaseDataType.UWORD))
assignExpressionToRegister(ptrAndIndex.second, RegisterOrPair.Y)
if(saveA) out(" pla")
out(" sta (P8ZP_SCRATCH_W2),y")
} else {
pushCpuStack(BaseDataType.UBYTE, ptrAndIndex.second)
assignExpressionToVariable(ptrAndIndex.first, "P8ZP_SCRATCH_W2", DataType.forDt(BaseDataType.UWORD))
restoreRegisterStack(CpuRegister.Y, true)
if(saveA) out(" pla")
out(" sta (P8ZP_SCRATCH_W2),y")
}
assignExpressionToVariable(ptrAndIndex.first, "P8ZP_SCRATCH_W2", DataType.forDt(BaseDataType.UWORD))
out(" ldy #${256-constOffset} ; negative offset $constOffset")
out(" dec P8ZP_SCRATCH_W2+1 | sta (P8ZP_SCRATCH_W2),y | inc P8ZP_SCRATCH_W2+1") // temporarily make MSB 1 less
return true
}
return true
*/
}
} else {
@@ -1367,8 +1352,19 @@ $repeatLabel""")
}
if(constOffset!=null) {
println("MEMREAD POINTER - $constOffset ${addressExpr.position}") // TODO
// TODO optimize more cases
val pointervar = ptrAndIndex.first as? PtIdentifier
if(pointervar!=null && isZpVar(pointervar)) {
val varname = asmSymbolName(pointervar)
out(" ldy #${256-constOffset} ; negative offset $constOffset")
out(" dec $varname+1 | lda ($varname),y | inc $varname+1") // temporarily make MSB 1 less
return true
} else {
// copy the pointer var to zp first
assignExpressionToVariable(ptrAndIndex.first, "P8ZP_SCRATCH_W2", DataType.forDt(BaseDataType.UWORD))
out(" ldy #${256-constOffset} ; negative offset $constOffset")
out(" dec P8ZP_SCRATCH_W2+1 | lda (P8ZP_SCRATCH_W2),y | inc P8ZP_SCRATCH_W2+1") // temporarily make MSB 1 less
return true
}
}
}
}