Apple-2-SW/prog8
1
0
Fork 0
mirror of https://github.com/irmen/prog8.git synced 2024-08-20 21:29:18 +00:00
Code Issues Projects Releases Wiki Activity

binexpr expression splitter for assignments

Browse Source
This commit is contained in:
Irmen de Jong 2020-10-02 00:04:21 +02:00
parent 9cd3a9f8e8
commit 110f877dcc
3 changed files with 105 additions and 45 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

116
compiler/src/prog8/optimizer/ExpressionSplitter.kt
View File

@ -3,44 +3,44 @@ package prog8.optimizer
import prog8.ast.INameScope
import prog8.ast.Node
import prog8.ast.Program
import prog8.ast.base.VarDeclType
import prog8.ast.expressions.*
import prog8.ast.processing.AstWalker
import prog8.ast.processing.IAstModification
import prog8.ast.statements.AssignTarget
import prog8.ast.statements.Assignment
import prog8.ast.statements.VarDecl
class ExpressionSplitter(private val program: Program) : AstWalker() {
// TODO once this works, integrate it back into expressionsimplifier
override fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> {
override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
if(assignment!=null) {
val expr = assignment.value as? BinaryExpression
if (expr != null) {
// reduce the complexity of a (binary) expression that has to be evaluated on the eval stack,
// by attempting to splitting it up into individual simple steps:
// X = <some-expression-not-X> <operator> <not-binary-expression>
// or X = <not-binary-expression> <associativeoperator> <some-expression-not-X>
// split that into X = <some-expression-not-X> ; X = X <operator> <not-binary-expression>
val expr = decl.value as? BinaryExpression
if (expr != null) {
// reduce the complexity of a (binary) expression that has to be evaluated on the eval stack,
// by attempting to splitting it up into individual simple steps:
// X = <some-expression-not-X> <operator> <not-binary-expression>
// or X = <not-binary-expression> <associativeoperator> <some-expression-not-X>
// split that into X = <some-expression-not-X> ; X = X <operator> <not-binary-expression>
// TODO FIX THIS, IT SOMETIMES JUST LOOPS... (for example on plasma.p8)
if (expr.operator !in comparisonOperators && !assignment.isAugmentable && isSimpleTarget(assignment.target, program.namespace)) {
if (expr.right !is BinaryExpression) {
println("SPLIT RIGHT BINEXPR $expr")
val firstAssign = Assignment(assignment.target, expr.left, assignment.position)
val augExpr = BinaryExpression(assignment.target.toExpression(), expr.operator, expr.right, expr.position)
return listOf(
IAstModification.InsertBefore(assignment, firstAssign, parent),
IAstModification.ReplaceNode(assignment.value, augExpr, assignment)
)
} else if (expr.left !is BinaryExpression && expr.operator in associativeOperators) {
println("SPLIT LEFT BINEXPR $expr")
val firstAssign = Assignment(assignment.target, expr.right, assignment.position)
val augExpr = BinaryExpression(assignment.target.toExpression(), expr.operator, expr.left, expr.position)
return listOf(
IAstModification.InsertBefore(assignment, firstAssign, parent),
IAstModification.ReplaceNode(assignment.value, augExpr, assignment))
}
// TODO DOES THIS LOOP AS WELL?
if (expr.operator !in comparisonOperators && decl.type==VarDeclType.VAR) {
if (expr.right !is BinaryExpression) {
println("SPLIT VARDECL RIGHT BINEXPR $expr") // TODO
// val firstAssign = Assignment(assignment.target, expr.left, assignment.position)
// val augExpr = BinaryExpression(assignment.target.toExpression(), expr.operator, expr.right, expr.position)
// return listOf(
// IAstModification.InsertBefore(assignment, firstAssign, parent),
// IAstModification.ReplaceNode(assignment.value, augExpr, assignment)
// )
} else if (expr.left !is BinaryExpression && expr.operator in associativeOperators) {
println("SPLIT VARDECL LEFT BINEXPR $expr") // TODO
// val firstAssign = Assignment(assignment.target, expr.right, assignment.position)
// val augExpr = BinaryExpression(assignment.target.toExpression(), expr.operator, expr.left, expr.position)
// return listOf(
// IAstModification.InsertBefore(assignment, firstAssign, parent),
// IAstModification.ReplaceNode(assignment.value, augExpr, assignment))
}
}
}
@ -48,13 +48,73 @@ class ExpressionSplitter(private val program: Program) : AstWalker() {
return emptyList()
}
// TODO once this works, integrate it back into expressionsimplifier
override fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> {
val binExpr = assignment.value as? BinaryExpression
if (binExpr != null) {
/*
reduce the complexity of a (binary) expression that has to be evaluated on the eval stack,
by attempting to splitting it up into individual simple steps:
X = BinExpr X = LeftExpr
<operator> followed by
/ \ IF 'X' not used X = BinExpr
/ \ IN LEFTEXPR ==> <operator>
/ \ / \
LeftExpr. RightExpr. / \
/ \ / \ X RightExpr.
.. .. .. ..
X = BinExpr X = RightExpr
<operator> followed by
/ \ IF ASSOCIATIVE X = BinExpr
/ \ <operator> ==> <operator>
/ \ / \
LeftExpr. SimpleExpr. / \
/ \ (not X) X LeftExpr.
.. ..
*/
if(!assignment.isAugmentable && isSimpleTarget(assignment.target, program.namespace)) {
val firstAssign = Assignment(assignment.target, binExpr.left, binExpr.left.position)
val targetExpr = assignment.target.toExpression()
val augExpr = BinaryExpression(targetExpr, binExpr.operator, binExpr.right, binExpr.right.position)
return listOf(
IAstModification.InsertBefore(assignment, firstAssign, parent),
IAstModification.ReplaceNode(assignment.value, augExpr, assignment))
}
if(binExpr.operator in associativeOperators && binExpr.left is BinaryExpression) {
if (binExpr.right !is BinaryExpression && !(binExpr.right isSameAs assignment.target)) {
val firstAssign = Assignment(assignment.target, binExpr.right, binExpr.right.position)
val targetExpr = assignment.target.toExpression()
val augExpr = BinaryExpression(targetExpr, binExpr.operator, binExpr.left, binExpr.left.position)
return listOf(
IAstModification.InsertBefore(assignment, firstAssign, parent),
IAstModification.ReplaceNode(assignment.value, augExpr, assignment))
}
}
// TODO further unraveling of binary expression trees into flat statements.
// however this should probably be done in a more generic way to also service
// the expressiontrees that are not used in an assignment statement...
}
return emptyList()
}
private fun isSimpleTarget(target: AssignTarget, namespace: INameScope): Boolean {
return when {
target.identifier!=null -> target.isInRegularRAM(namespace)
target.memoryAddress!=null -> target.isInRegularRAM(namespace)
target.arrayindexed!=null -> {
val index = target.arrayindexed!!.arrayspec.index
if(index is NumericLiteralValue || index is IdentifierReference)
if(index is NumericLiteralValue)
target.isInRegularRAM(namespace)
else
false

6
compiler/src/prog8/optimizer/Extensions.kt
View File

@ -55,8 +55,8 @@ internal fun Program.simplifyExpressions() : Int {
}
internal fun Program.splitExpressions() : Int {
val opti = ExpressionSplitter(this)
opti.visit(this)
return opti.applyModifications()
val splitter = ExpressionSplitter(this)
splitter.visit(this)
return splitter.applyModifications()
}

28
examples/test.p8
View File

@ -19,20 +19,20 @@ main {
; uword[] arrays = [names, names3, values]
asmsub testX() {
%asm {{
stx _saveX
lda #13
jsr txt.chrout
lda _saveX
jsr txt.print_ub
lda #13
jsr txt.chrout
ldx _saveX
rts
_saveX .byte 0
}}
}
; asmsub testX() {
; %asm {{
; stx _saveX
; lda #13
; jsr txt.chrout
; lda _saveX
; jsr txt.print_ub
; lda #13
; jsr txt.chrout
; ldx _saveX
; rts
;_saveX .byte 0
; }}
; }
sub start() {
; byte bb = 100