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Long comparisons; word vs unsigned byte comparison optimization
This commit is contained in:
Karol Stasiak
parent
2548822b8b
commit
e0c3a566b7
@ -122,18 +122,18 @@ Note that currently in cases like `a < f() < b`, `f()` will be evaluated twice!
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* `==`: equality
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`byte == byte`
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`word == word`
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`long == long`
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`simple word == simple word`
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`simple long == simple long`
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* `!=`: inequality
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`byte != byte`
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`word != word`
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`long != long`
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`simple word != simple word`
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`simple long != simple long`
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* `>`, `<`, `<=`, `>=`: inequality
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`byte > byte`
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`word > word`
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`long > long`
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`simple word > simple word`
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`simple long > simple long`
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Currently, `>`, `<`, `<=`, `>=` operators perform unsigned comparison
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if none of the types of their arguments is signed,
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@ -465,8 +465,8 @@ object BuiltIns {
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val lva = env.get[VariableInMemory](v.name)
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(AssemblyLine.variable(ctx, STA, lva, 1),
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AssemblyLine.variable(ctx, STA, lva, 0),
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List(AssemblyLine.immediate(STA, rc.hiByte)),
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List(AssemblyLine.immediate(STA, rc.loByte)))
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List(AssemblyLine.immediate(STA, rc.hiByte.quickSimplify)),
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List(AssemblyLine.immediate(STA, rc.loByte.quickSimplify)))
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case (lv: VariableExpression, None, rv: VariableExpression, None) =>
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val lva = env.get[VariableInMemory](lv.name)
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val rva = env.get[VariableInMemory](rv.name)
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@ -474,9 +474,27 @@ object BuiltIns {
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AssemblyLine.variable(ctx, STA, lva, 0),
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AssemblyLine.variable(ctx, STA, rva, 1),
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AssemblyLine.variable(ctx, STA, rva, 0))
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case _ =>
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// TODO comparing expressions
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ErrorReporting.error("Too complex expressions in comparison", lhs.position)
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(Nil, Nil, Nil, Nil)
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}
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val lType = ExpressionCompiler.getExpressionType(ctx, lhs)
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val rType = ExpressionCompiler.getExpressionType(ctx, rhs)
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val compactEqualityComparison = if (ctx.options.flag(CompilationFlag.OptimizeForSpeed)) {
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None
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} else if (lType.size == 1 && !lType.isSigned) {
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Some(staTo(LDA, ll) ++ staTo(EOR, rl) ++ staTo(ORA, rh))
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} else if (rType.size == 1 && !rType.isSigned) {
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Some(staTo(LDA, rl) ++ staTo(EOR, ll) ++ staTo(ORA, lh))
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} else {
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None
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}
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effectiveComparisonType match {
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case ComparisonType.Equal =>
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compactEqualityComparison match {
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case Some(code) => code :+ AssemblyLine.relative(BEQ, Label(x))
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case None =>
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val innerLabel = MfCompiler.nextLabel("cp")
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staTo(LDA, ll) ++
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staTo(CMP, rl) ++
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@ -486,14 +504,19 @@ object BuiltIns {
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List(
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AssemblyLine.relative(BEQ, Label(x)),
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AssemblyLine.label(innerLabel))
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}
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case ComparisonType.NotEqual =>
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compactEqualityComparison match {
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case Some(code) => code :+ AssemblyLine.relative(BNE, Label(x))
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case None =>
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staTo(LDA, ll) ++
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staTo(CMP, rl) ++
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List(AssemblyLine.relative(BNE, Label(x))) ++
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staTo(LDA, lh) ++
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staTo(CMP, rh) ++
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List(AssemblyLine.relative(BNE, Label(x)))
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}
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case ComparisonType.LessUnsigned =>
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val innerLabel = MfCompiler.nextLabel("cp")
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@ -546,6 +569,91 @@ object BuiltIns {
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}
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}
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def compileLongComparison(ctx: CompilationContext, compType: ComparisonType.Value, lhs: Expression, rhs: Expression, size:Int, branches: BranchSpec, alreadyFlipped: Boolean = false): List[AssemblyLine] = {
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val rType = ExpressionCompiler.getExpressionType(ctx, rhs)
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if (rType.size < size && rType.isSigned) {
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if (alreadyFlipped) ???
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else return compileLongComparison(ctx, ComparisonType.flip(compType), rhs, lhs, size, branches, alreadyFlipped = true)
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}
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val (effectiveComparisonType, label) = branches match {
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case NoBranching => return Nil
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case BranchIfTrue(x) => compType -> x
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case BranchIfFalse(x) => ComparisonType.negate(compType) -> x
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}
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// TODO: check for carry flag clobbering
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val l = getLoadForEachByte(ctx, lhs, size)
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val r = getLoadForEachByte(ctx, rhs, size)
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val mask = (1L << (size * 8)) - 1
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(ctx.env.eval(lhs), ctx.env.eval(rhs)) match {
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case (Some(NumericConstant(lc, _)), Some(NumericConstant(rc, _))) =>
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return if (effectiveComparisonType match {
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// TODO: those masks are probably wrong
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case ComparisonType.Equal =>
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(lc & mask) == (rc & mask) // ??
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case ComparisonType.NotEqual =>
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(lc & mask) != (rc & mask) // ??
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case ComparisonType.LessOrEqualUnsigned =>
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(lc & mask) <= (rc & mask)
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case ComparisonType.GreaterOrEqualUnsigned =>
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(lc & mask) >= (rc & mask)
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case ComparisonType.GreaterUnsigned =>
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(lc & mask) > (rc & mask)
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case ComparisonType.LessUnsigned =>
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(lc & mask) < (rc & mask)
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case ComparisonType.LessOrEqualSigned =>
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signExtend(lc, mask) <= signExtend(lc, mask)
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case ComparisonType.GreaterOrEqualSigned =>
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signExtend(lc, mask) >= signExtend(lc, mask)
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case ComparisonType.GreaterSigned =>
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signExtend(lc, mask) > signExtend(lc, mask)
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case ComparisonType.LessSigned =>
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signExtend(lc, mask) < signExtend(lc, mask)
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}) List(AssemblyLine.absolute(JMP, Label(label))) else Nil
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case _ =>
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effectiveComparisonType match {
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case ComparisonType.Equal =>
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val innerLabel = MfCompiler.nextLabel("cp")
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val bytewise = l.zip(r).map{
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case (staL, staR) => staTo(LDA, staL) ++ staTo(CMP, staR)
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}
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bytewise.init.flatMap(b => b :+ AssemblyLine.relative(BNE, innerLabel)) ++ bytewise.last ++List(
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AssemblyLine.relative(BEQ, Label(label)),
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AssemblyLine.label(innerLabel))
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case ComparisonType.NotEqual =>
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l.zip(r).flatMap {
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case (staL, staR) => staTo(LDA, staL) ++ staTo(CMP, staR) :+ AssemblyLine.relative(BNE, label)
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}
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case ComparisonType.LessUnsigned =>
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val calculateCarry = AssemblyLine.implied(SEC) :: l.zip(r).flatMap{
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case (staL, staR) => staTo(LDA, staL) ++ staTo(SBC, staR)
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}
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calculateCarry ++ List(AssemblyLine.relative(BCC, Label(label)))
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case ComparisonType.GreaterOrEqualUnsigned =>
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val calculateCarry = AssemblyLine.implied(SEC) :: l.zip(r).flatMap{
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case (staL, staR) => staTo(LDA, staL) ++ staTo(SBC, staR)
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}
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calculateCarry ++ List(AssemblyLine.relative(BCS, Label(label)))
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case ComparisonType.GreaterUnsigned | ComparisonType.LessOrEqualUnsigned =>
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compileLongComparison(ctx, ComparisonType.flip(compType), rhs, lhs, size, branches, alreadyFlipped = true)
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case _ =>
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ErrorReporting.error("Long signed comparisons are not yet supported", lhs.position)
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Nil
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}
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}
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}
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private def signExtend(value: Long, mask: Long): Long = {
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val masked = value & mask
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if (masked > mask/2) masked | ~mask
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else masked
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}
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def compileInPlaceByteMultiplication(ctx: CompilationContext, v: LhsExpression, addend: Expression): List[AssemblyLine] = {
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val b = ctx.env.get[Type]("byte")
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ctx.env.eval(addend) match {
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@ -1068,6 +1176,47 @@ object BuiltIns {
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???
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}
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}
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private def getLoadForEachByte(ctx: CompilationContext, expr: Expression, size: Int): List[List[AssemblyLine]] = {
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val env = ctx.env
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env.eval(expr) match {
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case Some(c) =>
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List.tabulate(size) { i => List(AssemblyLine.immediate(STA, c.subbyte(i))) }
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case None =>
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expr match {
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case v: VariableExpression =>
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val variable = env.get[Variable](v.name)
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List.tabulate(size) { i =>
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if (i < variable.typ.size) {
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AssemblyLine.variable(ctx, STA, variable, i)
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} else if (variable.typ.isSigned) {
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val label = MfCompiler.nextLabel("sx")
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AssemblyLine.variable(ctx, STA, variable, i) ++ List(
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AssemblyLine.immediate(ORA, 0x7F),
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AssemblyLine.relative(BMI, label),
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AssemblyLine.immediate(STA, 0),
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AssemblyLine.label(label))
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} else List(AssemblyLine.immediate(STA, 0))
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}
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case expr@IndexedExpression(variable, index) =>
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List.tabulate(size) { i =>
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if (i == 0) ExpressionCompiler.compileByteStorage(ctx, Register.A, expr)
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else List(AssemblyLine.immediate(STA, 0))
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}
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case SeparateBytesExpression(h: LhsExpression, l: LhsExpression) =>
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if (simplicity(ctx.env, h) < 'J' || simplicity(ctx.env, l) < 'J') {
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// a[b]:c[d] is the most complex expression that doesn't cause the following warning
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ErrorReporting.warn("Too complex expression given to the `:` operator, generated code might be wrong", ctx.options, expr.position)
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}
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List.tabulate(size) { i =>
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if (i == 0) getStorageForEachByte(ctx, l).head
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else if (i == 1) ExpressionCompiler.preserveRegisterIfNeeded(ctx, Register.A, getStorageForEachByte(ctx, h).head)
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else List(AssemblyLine.immediate(STA, 0))
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}
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case _ =>
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???
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}
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}
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}
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private def removeTsx(codes: List[List[AssemblyLine]]): List[List[AssemblyLine]] = codes.map {
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case List(AssemblyLine(TSX, _, _, _), AssemblyLine(op, AbsoluteX, NumericConstant(nn, _), _)) if nn >= 0x100 && nn <= 0x1ff =>
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@ -931,6 +931,7 @@ object ExpressionCompiler {
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size match {
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case 1 => BuiltIns.compileByteComparison(ctx, if (signed) ComparisonType.LessSigned else ComparisonType.LessUnsigned, l, r, branches)
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case 2 => BuiltIns.compileWordComparison(ctx, if (signed) ComparisonType.LessSigned else ComparisonType.LessUnsigned, l, r, branches)
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case _ => BuiltIns.compileLongComparison(ctx, if (signed) ComparisonType.LessSigned else ComparisonType.LessUnsigned, l, r, size, branches)
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}
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}
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case ">=" =>
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@ -940,6 +941,7 @@ object ExpressionCompiler {
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size match {
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case 1 => BuiltIns.compileByteComparison(ctx, if (signed) ComparisonType.GreaterOrEqualSigned else ComparisonType.GreaterOrEqualUnsigned, l, r, branches)
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case 2 => BuiltIns.compileWordComparison(ctx, if (signed) ComparisonType.GreaterOrEqualSigned else ComparisonType.GreaterOrEqualUnsigned, l, r, branches)
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case _ => BuiltIns.compileLongComparison(ctx, if (signed) ComparisonType.GreaterOrEqualSigned else ComparisonType.GreaterOrEqualUnsigned, l, r, size, branches)
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}
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}
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case ">" =>
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@ -949,6 +951,7 @@ object ExpressionCompiler {
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size match {
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case 1 => BuiltIns.compileByteComparison(ctx, if (signed) ComparisonType.GreaterSigned else ComparisonType.GreaterUnsigned, l, r, branches)
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case 2 => BuiltIns.compileWordComparison(ctx, if (signed) ComparisonType.GreaterSigned else ComparisonType.GreaterUnsigned, l, r, branches)
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case _ => BuiltIns.compileLongComparison(ctx, if (signed) ComparisonType.GreaterSigned else ComparisonType.GreaterUnsigned, l, r, size, branches)
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}
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}
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case "<=" =>
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@ -958,6 +961,7 @@ object ExpressionCompiler {
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size match {
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case 1 => BuiltIns.compileByteComparison(ctx, if (signed) ComparisonType.LessOrEqualSigned else ComparisonType.LessOrEqualUnsigned, l, r, branches)
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case 2 => BuiltIns.compileWordComparison(ctx, if (signed) ComparisonType.LessOrEqualSigned else ComparisonType.LessOrEqualUnsigned, l, r, branches)
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case _ => BuiltIns.compileLongComparison(ctx, if (signed) ComparisonType.LessOrEqualSigned else ComparisonType.LessOrEqualUnsigned, l, r, size, branches)
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}
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}
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case "==" =>
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@ -966,6 +970,7 @@ object ExpressionCompiler {
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size match {
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case 1 => BuiltIns.compileByteComparison(ctx, ComparisonType.Equal, l, r, branches)
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case 2 => BuiltIns.compileWordComparison(ctx, ComparisonType.Equal, l, r, branches)
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case _ => BuiltIns.compileLongComparison(ctx, ComparisonType.Equal, l, r, size, branches)
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}
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}
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case "!=" =>
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@ -973,6 +978,7 @@ object ExpressionCompiler {
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size match {
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case 1 => BuiltIns.compileByteComparison(ctx, ComparisonType.NotEqual, l, r, branches)
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case 2 => BuiltIns.compileWordComparison(ctx, ComparisonType.NotEqual, l, r, branches)
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case _ => BuiltIns.compileLongComparison(ctx, ComparisonType.NotEqual, l, r, size, branches)
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}
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case "+=" =>
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val (l, r, size) = assertAssignmentLike(ctx, params)
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@ -23,7 +23,7 @@ class ComparisonSuite extends FunSuite with Matchers {
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| output += 78
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| }
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| }
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""".stripMargin)(_.readWord(0xc000) should equal(6))
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""".stripMargin)(_.readByte(0xc000) should equal(6))
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}
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test("Less") {
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@ -36,7 +36,7 @@ class ComparisonSuite extends FunSuite with Matchers {
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| output += 1
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| }
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| }
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""".stripMargin)(_.readWord(0xc000) should equal(150))
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""".stripMargin)(_.readByte(0xc000) should equal(150))
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}
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test("Compare to zero") {
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@ -51,7 +51,7 @@ class ComparisonSuite extends FunSuite with Matchers {
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| output += 1
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| }
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| }
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""".stripMargin)(_.readWord(0xc000) should equal(150))
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""".stripMargin)(_.readByte(0xc000) should equal(150))
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}
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test("Carry flag optimization test") {
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@ -71,7 +71,7 @@ class ComparisonSuite extends FunSuite with Matchers {
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| byte get(byte x) {
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| if x >= 6 {return 0} else {return 128}
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| }
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""".stripMargin)(_.readWord(0xc000) should equal(4))
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""".stripMargin)(_.readByte(0xc000) should equal(4))
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}
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test("Does it even work") {
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@ -98,7 +98,7 @@ class ComparisonSuite extends FunSuite with Matchers {
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| if 2222 == 3333 { output -= 1 }
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| }
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""".stripMargin
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EmuBenchmarkRun(src)(_.readWord(0xc000) should equal(src.count(_ == '+')))
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EmuBenchmarkRun(src)(_.readByte(0xc000) should equal(src.count(_ == '+')))
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}
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test("Word comparison == and !=") {
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@ -118,9 +118,10 @@ class ComparisonSuite extends FunSuite with Matchers {
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| if a != c { output += 1 }
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| if a != 5 { output += 1 }
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| if a != 260 { output += 1 }
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| if a != 0 { output += 1 }
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| }
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""".stripMargin
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EmuBenchmarkRun(src)(_.readWord(0xc000) should equal(src.count(_ == '+')))
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EmuBenchmarkRun(src)(_.readByte(0xc000) should equal(src.count(_ == '+')))
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}
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test("Word comparison <=") {
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@ -141,7 +142,7 @@ class ComparisonSuite extends FunSuite with Matchers {
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| if a <= c { output += 1 }
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| }
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""".stripMargin
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EmuBenchmarkRun(src)(_.readWord(0xc000) should equal(src.count(_ == '+')))
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EmuBenchmarkRun(src)(_.readByte(0xc000) should equal(src.count(_ == '+')))
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}
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test("Word comparison <") {
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val src =
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@ -160,7 +161,7 @@ class ComparisonSuite extends FunSuite with Matchers {
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| if a < 257 { output += 1 }
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| }
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""".stripMargin
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EmuBenchmarkRun(src)(_.readWord(0xc000) should equal(src.count(_ == '+')))
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EmuBenchmarkRun(src)(_.readByte(0xc000) should equal(src.count(_ == '+')))
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}
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@ -181,7 +182,7 @@ class ComparisonSuite extends FunSuite with Matchers {
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| if c > 0 { output += 1 }
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| }
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""".stripMargin
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EmuBenchmarkRun(src)(_.readWord(0xc000) should equal(src.count(_ == '+')))
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EmuBenchmarkRun(src)(_.readByte(0xc000) should equal(src.count(_ == '+')))
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}
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test("Word comparison >=") {
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@ -204,7 +205,7 @@ class ComparisonSuite extends FunSuite with Matchers {
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| if a >= 0 { output += 1 }
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| }
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""".stripMargin
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EmuBenchmarkRun(src)(_.readWord(0xc000) should equal(src.count(_ == '+')))
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EmuBenchmarkRun(src)(_.readByte(0xc000) should equal(src.count(_ == '+')))
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}
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test("Signed comparison >=") {
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@ -227,7 +228,7 @@ class ComparisonSuite extends FunSuite with Matchers {
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| if a >= 0 { output += 1 }
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| }
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""".stripMargin
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EmuBenchmarkRun(src)(_.readWord(0xc000) should equal(src.count(_ == '+')))
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EmuBenchmarkRun(src)(_.readByte(0xc000) should equal(src.count(_ == '+')))
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}
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test("Signed comparison < and <=") {
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@ -259,7 +260,7 @@ class ComparisonSuite extends FunSuite with Matchers {
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| if c <= -1 { output -= 7 }
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| }
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""".stripMargin
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EmuBenchmarkRun(src)(_.readWord(0xc000) should equal(src.count(_ == '+')))
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EmuBenchmarkRun(src)(_.readByte(0xc000) should equal(src.count(_ == '+')))
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}
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test("Multiple params for equality") {
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@ -275,7 +276,7 @@ class ComparisonSuite extends FunSuite with Matchers {
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| output += 78
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| }
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| }
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""".stripMargin)(_.readWord(0xc000) should equal(6))
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""".stripMargin)(_.readByte(0xc000) should equal(6))
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}
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test("Multiple params for inequality") {
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@ -291,7 +292,7 @@ class ComparisonSuite extends FunSuite with Matchers {
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| output += 78
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| }
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| }
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""".stripMargin)(_.readWord(0xc000) should equal(6))
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""".stripMargin)(_.readByte(0xc000) should equal(6))
|
||||
}
|
||||
|
||||
test("Warnings") {
|
||||
@ -310,6 +311,33 @@ class ComparisonSuite extends FunSuite with Matchers {
|
||||
| byte three() {
|
||||
| return 3
|
||||
| }
|
||||
""".stripMargin)(_.readWord(0xc000) should equal(6))
|
||||
""".stripMargin)(_.readByte(0xc000) should equal(6))
|
||||
}
|
||||
|
||||
test("Long comparisons") {
|
||||
val src =
|
||||
"""
|
||||
| byte output @$c000
|
||||
| void main () {
|
||||
| long a
|
||||
| long b
|
||||
| long c
|
||||
| output = 0
|
||||
| a = 1234567
|
||||
| b = 2345678
|
||||
| c = 1234599
|
||||
| if a == a { output += 1 }
|
||||
| if c >= a { output += 1 }
|
||||
| if c != a { output += 1 }
|
||||
| if a <= c { output += 1 }
|
||||
| if a < c { output += 1 }
|
||||
| if b >= a { output += 1 }
|
||||
| if b >= 0 { output += 1 }
|
||||
| if b >= 44564 { output += 1 }
|
||||
| if a >= 335444 { output += 1 }
|
||||
| if c > 335444 { output += 1 }
|
||||
| }
|
||||
""".stripMargin
|
||||
EmuBenchmarkRun(src)(_.readByte(0xc000) should equal(src.count(_ == '+')))
|
||||
}
|
||||
}
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user