fixed ast parent link bug in AstWalker, rewrote StatementReorderer using new API, when labels are sorted.

This commit is contained in:
Irmen de Jong 2020-04-06 14:31:02 +02:00
parent 95e76058d3
commit ed54cf680a
5 changed files with 120 additions and 148 deletions

View File

@ -24,8 +24,9 @@ internal fun Program.reorderStatements() {
initvalueCreator.visit(this)
initvalueCreator.applyModifications()
val checker = StatementReorderer(this)
checker.visit(this)
val reorder = StatementReorderer(this)
reorder.visit(this)
reorder.applyModifications()
}
internal fun Program.addTypecasts(errors: ErrorReporter) {

View File

@ -22,7 +22,7 @@ internal class AstChecker(private val program: Program,
if(mainBlocks.size>1)
errors.err("more than one 'main' block", mainBlocks[0].position)
if(mainBlocks.isEmpty())
errors.err("there is no 'main' block", program.position)
errors.err("there is no 'main' block", program.modules.firstOrNull()?.position ?: program.position)
for(mainBlock in mainBlocks) {
val startSub = mainBlock.subScopes()["start"] as? Subroutine

View File

@ -56,7 +56,7 @@ interface IAstModification {
class ReplaceNode(val node: Node, val replacement: Node, val parent: Node) : IAstModification {
override fun perform() {
parent.replaceChildNode(node, replacement)
replacement.parent = parent
replacement.linkParents(parent)
}
}

View File

@ -9,187 +9,133 @@ import prog8.ast.expressions.*
import prog8.ast.statements.*
internal class StatementReorderer(private val program: Program): IAstModifyingVisitor {
internal class StatementReorderer(val program: Program) : AstWalker() {
// Reorders the statements in a way the compiler needs.
// - 'main' block must be the very first statement UNLESS it has an address set.
// - blocks are ordered by address, where blocks without address are put at the end.
// - in every scope:
// -- the directives '%output', '%launcher', '%zeropage', '%zpreserved', '%address' and '%option' will come first.
// -- all vardecls then follow.
// -- the remaining statements then follow in their original order.
//
// - the 'start' subroutine in the 'main' block will be moved to the top immediately following the directives.
// - all other subroutines will be moved to the end of their block.
// - library blocks are put last.
// - blocks are ordered by address, where blocks without address are placed last.
// - in every scope, most directives and vardecls are moved to the top.
// - the 'start' subroutine is moved to the top.
// - (syntax desugaring) a vardecl with a non-const initializer value is split into a regular vardecl and an assignment statement.
// - (syntax desugaring) augmented assignment is turned into regular assignment.
// - (syntax desugaring) struct value assignment is expanded into several struct member assignments.
// - sorts the choices in when statement.
// - a vardecl with a non-const initializer value is split into a regular vardecl and an assignment statement.
private val directivesToMove = setOf("%output", "%launcher", "%zeropage", "%zpreserved", "%address", "%option")
private val addVardecls = mutableMapOf<INameScope, MutableList<VarDecl>>()
override fun visit(module: Module) {
addVardecls.clear()
super.visit(module)
override fun after(module: Module, parent: Node): Iterable<IAstModification> {
val (blocks, other) = module.statements.partition { it is Block }
module.statements = other.asSequence().plus(blocks.sortedBy { (it as Block).address ?: Int.MAX_VALUE }).toMutableList()
// make sure user-defined blocks come BEFORE library blocks, and move the "main" block to the top of everything
val nonLibraryBlocks = module.statements.withIndex()
.filter { it.value is Block && !(it.value as Block).isInLibrary }
.map { it.index to it.value }
.reversed()
for(nonLibBlock in nonLibraryBlocks)
module.statements.removeAt(nonLibBlock.first)
for(nonLibBlock in nonLibraryBlocks)
module.statements.add(0, nonLibBlock.second)
val mainBlock = module.statements.singleOrNull { it is Block && it.name=="main" }
if(mainBlock!=null && (mainBlock as Block).address==null) {
module.remove(mainBlock)
val mainBlock = module.statements.filterIsInstance<Block>().firstOrNull { it.name=="main" }
if(mainBlock!=null && mainBlock.address==null) {
module.statements.remove(mainBlock)
module.statements.add(0, mainBlock)
}
val varDecls = module.statements.filterIsInstance<VarDecl>()
module.statements.removeAll(varDecls)
module.statements.addAll(0, varDecls)
val directives = module.statements.filter {it is Directive && it.directive in directivesToMove}
module.statements.removeAll(directives)
module.statements.addAll(0, directives)
for((where, decls) in addVardecls) {
where.statements.addAll(0, decls)
decls.forEach { it.linkParents(where as Node) }
}
reorderVardeclsAndDirectives(module.statements)
return emptyList()
}
override fun visit(block: Block): Statement {
private fun reorderVardeclsAndDirectives(statements: MutableList<Statement>) {
val varDecls = statements.filterIsInstance<VarDecl>()
statements.removeAll(varDecls)
statements.addAll(0, varDecls)
val subroutines = block.statements.filterIsInstance<Subroutine>()
var numSubroutinesAtEnd = 0
// move all subroutines to the end of the block
for (subroutine in subroutines) {
if(subroutine.name!="start" || block.name!="main") {
block.remove(subroutine)
block.statements.add(subroutine)
}
numSubroutinesAtEnd++
val directives = statements.filterIsInstance<Directive>().filter {it.directive in directivesToMove}
statements.removeAll(directives)
statements.addAll(0, directives)
}
override fun before(block: Block, parent: Node): Iterable<IAstModification> {
parent as Module
if(block.isInLibrary) {
return listOf(
IAstModification.Remove(block, parent),
IAstModification.InsertAfter(parent.statements.last(), block, parent)
)
}
// move the "start" subroutine to the top
if(block.name=="main") {
block.statements.singleOrNull { it is Subroutine && it.name == "start" } ?.let {
block.remove(it)
block.statements.add(0, it)
numSubroutinesAtEnd--
reorderVardeclsAndDirectives(block.statements)
return emptyList()
}
override fun before(subroutine: Subroutine, parent: Node): Iterable<IAstModification> {
if(subroutine.name=="start" && parent is Block) {
if(parent.statements.filterIsInstance<Subroutine>().first().name!="start") {
return listOf(
IAstModification.Remove(subroutine, parent),
IAstModification.InsertFirst(subroutine, parent)
)
}
}
val varDecls = block.statements.filterIsInstance<VarDecl>()
block.statements.removeAll(varDecls)
block.statements.addAll(0, varDecls)
val directives = block.statements.filter {it is Directive && it.directive in directivesToMove}
block.statements.removeAll(directives)
block.statements.addAll(0, directives)
block.linkParents(block.parent)
return super.visit(block)
reorderVardeclsAndDirectives(subroutine.statements)
return emptyList()
}
override fun visit(subroutine: Subroutine): Statement {
super.visit(subroutine)
val varDecls = subroutine.statements.filterIsInstance<VarDecl>()
subroutine.statements.removeAll(varDecls)
subroutine.statements.addAll(0, varDecls)
val directives = subroutine.statements.filter {it is Directive && it.directive in directivesToMove}
subroutine.statements.removeAll(directives)
subroutine.statements.addAll(0, directives)
return subroutine
}
private fun addVarDecl(scope: INameScope, variable: VarDecl): VarDecl {
if(scope !in addVardecls)
addVardecls[scope] = mutableListOf()
val declList = addVardecls.getValue(scope)
val existing = declList.singleOrNull { it.name==variable.name }
return if(existing!=null) {
existing
} else {
declList.add(variable)
variable
}
}
override fun visit(decl: VarDecl): Statement {
override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
val declValue = decl.value
if(declValue!=null && decl.type== VarDeclType.VAR && decl.datatype in NumericDatatypes) {
val declConstValue = declValue.constValue(program)
if(declConstValue==null) {
// move the vardecl (without value) to the scope and replace this with a regular assignment
decl.value = null
val target = AssignTarget(null, IdentifierReference(listOf(decl.name), decl.position), null, null, decl.position)
val assign = Assignment(target, null, declValue, decl.position)
assign.linkParents(decl.parent)
decl.value = null
addVarDecl(decl.definingScope(), decl)
return assign
return listOf(
IAstModification.ReplaceNode(decl, assign, parent),
IAstModification.InsertFirst(decl, decl.definingScope() as Node)
)
}
}
return super.visit(decl)
return emptyList()
}
override fun visit(assignment: Assignment): Statement {
val assg = super.visit(assignment)
if(assg !is Assignment)
return assg
override fun after(whenStatement: WhenStatement, parent: Node): Iterable<IAstModification> {
val choices = whenStatement.choiceValues(program).sortedBy {
it.first?.first() ?: Int.MAX_VALUE
}
whenStatement.choices.clear()
choices.mapTo(whenStatement.choices) { it.second }
return emptyList()
}
// see if a typecast is needed to convert the value's type into the proper target type
val valueItype = assg.value.inferType(program)
val targetItype = assg.target.inferType(program, assg)
override fun before(assignment: Assignment, parent: Node): Iterable<IAstModification> {
if(assignment.aug_op!=null) {
// TODO instead of desugaring augmented assignments, instead just keep them and use them for possibly more efficient code generation ?
// this also means that we should actually reverse this stuff below: A = A + 5 ---> A += 5
val leftOperand: Expression =
when {
assignment.target.register != null -> RegisterExpr(assignment.target.register!!, assignment.target.position)
assignment.target.identifier != null -> assignment.target.identifier!!
assignment.target.arrayindexed != null -> assignment.target.arrayindexed!!
assignment.target.memoryAddress != null -> DirectMemoryRead(assignment.target.memoryAddress!!.addressExpression, assignment.value.position)
else -> throw FatalAstException("strange assignment")
}
if(targetItype.isKnown && valueItype.isKnown) {
val targettype = targetItype.typeOrElse(DataType.STRUCT)
val valuetype = valueItype.typeOrElse(DataType.STRUCT)
val expression = BinaryExpression(leftOperand, assignment.aug_op.substringBeforeLast('='), assignment.value, assignment.position)
val convertedAssignment = Assignment(assignment.target, null, expression, assignment.position)
return listOf(IAstModification.ReplaceNode(assignment, convertedAssignment, parent))
}
// struct assignments will be flattened (if it's not a struct literal)
if (valuetype == DataType.STRUCT && targettype == DataType.STRUCT) {
val assignments = if (assg.value is StructLiteralValue) {
flattenStructAssignmentFromStructLiteral(assg, program) // 'structvar = { ..... } '
} else {
flattenStructAssignmentFromIdentifier(assg, program) // 'structvar1 = structvar2'
}
return if (assignments.isEmpty()) {
// something went wrong (probably incompatible struct types)
// we'll get an error later from the AstChecker
assg
} else {
val scope = AnonymousScope(assignments.toMutableList(), assg.position)
scope.linkParents(assg.parent)
scope
}
val valueType = assignment.value.inferType(program)
val targetType = assignment.target.inferType(program, assignment)
if(valueType.istype(DataType.STRUCT) && targetType.istype(DataType.STRUCT)) {
val assignments = if (assignment.value is StructLiteralValue) {
flattenStructAssignmentFromStructLiteral(assignment, program) // 'structvar = { ..... } '
} else {
flattenStructAssignmentFromIdentifier(assignment, program) // 'structvar1 = structvar2'
}
if(assignments.isNotEmpty()) {
val modifications = mutableListOf<IAstModification>()
assignments.reversed().mapTo(modifications) { IAstModification.InsertAfter(assignment, it, parent) }
modifications.add(IAstModification.Remove(assignment, parent))
return modifications
}
}
if(assg.aug_op!=null) {
// transform augmented assg into normal assg so we have one case less to deal with later
val newTarget: Expression =
when {
assg.target.register != null -> RegisterExpr(assg.target.register!!, assg.target.position)
assg.target.identifier != null -> assg.target.identifier!!
assg.target.arrayindexed != null -> assg.target.arrayindexed!!
assg.target.memoryAddress != null -> DirectMemoryRead(assg.target.memoryAddress!!.addressExpression, assg.value.position)
else -> throw FatalAstException("strange assg")
}
val expression = BinaryExpression(newTarget, assg.aug_op.substringBeforeLast('='), assg.value, assg.position)
expression.linkParents(assg.parent)
val convertedAssignment = Assignment(assg.target, null, expression, assg.position)
convertedAssignment.linkParents(assg.parent)
return super.visit(convertedAssignment)
}
return assg
return emptyList()
}
private fun flattenStructAssignmentFromStructLiteral(structAssignment: Assignment, program: Program): List<Assignment> {

View File

@ -3,6 +3,21 @@
%import c64flt
%zeropage basicsafe
foobar {
%option force_output
ubyte xx
sub derp() {
byte yy=cos8(A)
if A==0 {
; ubyte qq=cos8(A)
A=54
}
}
}
main {
sub start() {
@ -16,6 +31,16 @@ main {
c64flt.print_f(floats[0])
c64flt.print_f(floats[1])
foobar.derp()
when A {
100 -> Y=4
101 -> Y=5
1 -> Y=66
10 -> Y=77
else -> Y=9
}
A+=99
}
}