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6502: Shifting improvements and fixes

This commit is contained in:
Karol Stasiak 2018-08-16 22:03:27 +02:00
parent 74dbca1f53
commit b41f9bebc1
3 changed files with 30 additions and 3 deletions

View File

@ -205,6 +205,33 @@ object BuiltIns {
firstParamCompiled ++ remainingParamsCompiled
}
def maybeCompileShiftFromByteToWord(ctx: CompilationContext, l: Expression, r: Expression, left: Boolean): Option[List[AssemblyLine]] = {
val env = ctx.env
env.eval(r) match {
case Some(NumericConstant(n, _)) =>
l match {
case FunctionCallExpression(wordTypeName, List(param)) =>
if (AbstractExpressionCompiler.getExpressionType(ctx, param).size == 1 && env.maybeGet[Type](wordTypeName).exists(_.size == 2)) {
Some(MosExpressionCompiler.compileToA(ctx, param) ++ BuiltIns.compileShiftFromByteToWord(ctx, n.toInt, left))
} else {
None
}
}
case _ => None
}
}
def compileShiftFromByteToWord(ctx: CompilationContext, count: Int, left: Boolean): List[AssemblyLine] = {
if (count == 8) {
List(AssemblyLine.implied(TAX), AssemblyLine.immediate(LDA, 0))
} else {
List(AssemblyLine.implied(PHA)) ++
List.fill(8 - count)(AssemblyLine.implied(if (left) LSR else ASL)) ++
List(AssemblyLine.implied(TAX), AssemblyLine.implied(PLA)) ++
List.fill(count)(AssemblyLine.implied(if (left) ASL else LSR))
}
}
def compileShiftOps(opcode: Opcode.Value, ctx: CompilationContext, l: Expression, r: Expression): List[AssemblyLine] = {
val b = ctx.env.get[Type]("byte")
val firstParamCompiled = MosExpressionCompiler.compile(ctx, l, Some(b -> RegisterVariable(MosRegister.A, b)), NoBranching)

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@ -831,7 +831,7 @@ object MosExpressionCompiler extends AbstractExpressionCompiler[AssemblyLine] {
zeroExtend = true
BuiltIns.compileShiftOps(ASL, ctx, l, r)
case 2 =>
PseudoregisterBuiltIns.compileWordShiftOps(left = true, ctx, l, r)
BuiltIns.maybeCompileShiftFromByteToWord(ctx, l, r, left = true).getOrElse(PseudoregisterBuiltIns.compileWordShiftOps(left = true, ctx, l, r))
case _ =>
ctx.log.error("Long shift ops not supported", l.position)
Nil
@ -843,7 +843,7 @@ object MosExpressionCompiler extends AbstractExpressionCompiler[AssemblyLine] {
zeroExtend = true
BuiltIns.compileShiftOps(LSR, ctx, l, r)
case 2 =>
PseudoregisterBuiltIns.compileWordShiftOps(left = false, ctx, l, r)
BuiltIns.maybeCompileShiftFromByteToWord(ctx, l, r, left = false).getOrElse(PseudoregisterBuiltIns.compileWordShiftOps(left = false, ctx, l, r))
case _ =>
ctx.log.error("Long shift ops not supported", l.position)
Nil

View File

@ -229,7 +229,7 @@ object PseudoregisterBuiltIns {
val firstParamCompiled = MosExpressionCompiler.compile(ctx, l, Some(MosExpressionCompiler.getExpressionType(ctx, l) -> reg), NoBranching)
ctx.env.eval(r) match {
case Some(NumericConstant(0, _)) =>
Nil
List(AssemblyLine.zeropage(LDA, reg), AssemblyLine.zeropage(LDX, reg, 1))
case Some(NumericConstant(v, _)) if v > 0 =>
if (ctx.options.flag(CompilationFlag.EmitNative65816Opcodes)) {
firstParamCompiled ++