User defined blocks are sorted first, before library blocks. This prioritizes zero page allocation to user code (and makes reading the program easier)

compiler/src/prog8/ast/AST.kt

@@ -506,11 +506,11 @@ private class GlobalNamespace(override val name: String,
 class Block(override val name: String,
             val address: Int?,
             override var statements: MutableList<IStatement>,
+            val isInLibrary: Boolean,
             override val position: Position) : IStatement, INameScope {
     override lateinit var parent: Node
     val scopedname: String by lazy { makeScopedName(name).joinToString(".") }
 
-
     override fun linkParents(parent: Node) {
         this.parent = parent
         statements.forEach {it.linkParents(this)}
@@ -1754,7 +1754,7 @@ class RepeatLoop(var body: AnonymousScope,
 /***************** Antlr Extension methods to create AST ****************/
 
 fun prog8Parser.ModuleContext.toAst(name: String, isLibrary: Boolean, importedFrom: Path) : Module =
-        Module(name, modulestatement().asSequence().map { it.toAst() }.toMutableList(), toPosition(), isLibrary, importedFrom)
+        Module(name, modulestatement().asSequence().map { it.toAst(isLibrary) }.toMutableList(), toPosition(), isLibrary, importedFrom)
 
 
 private fun ParserRuleContext.toPosition() : Position {
@@ -1768,19 +1768,19 @@ private fun ParserRuleContext.toPosition() : Position {
 }
 
 
-private fun prog8Parser.ModulestatementContext.toAst() : IStatement {
+private fun prog8Parser.ModulestatementContext.toAst(isInLibrary: Boolean) : IStatement {
     val directive = directive()?.toAst()
     if(directive!=null) return directive
 
-    val block = block()?.toAst()
+    val block = block()?.toAst(isInLibrary)
     if(block!=null) return block
 
     throw FatalAstException(text)
 }
 
 
-private fun prog8Parser.BlockContext.toAst() : IStatement =
+private fun prog8Parser.BlockContext.toAst(isInLibrary: Boolean) : IStatement =
-        Block(identifier().text, integerliteral()?.toAst()?.number?.toInt(), statement_block().toAst(), toPosition())
+        Block(identifier().text, integerliteral()?.toAst()?.number?.toInt(), statement_block().toAst(), isInLibrary, toPosition())
 
 
 private fun prog8Parser.Statement_blockContext.toAst(): MutableList<IStatement> =

compiler/src/prog8/ast/StmtReorderer.kt

@@ -33,11 +33,21 @@ private class StatementReorderer(private val namespace: INameScope, private val
         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(blocks in nonLibraryBlocks)
+            module.statements.removeAt(blocks.first)
+        for(blocks in nonLibraryBlocks)
+            module.statements.add(0, blocks.second)
         val mainBlock = module.statements.single { it is Block && it.name=="main" }
         if((mainBlock as Block).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)
@@ -46,8 +56,6 @@ private class StatementReorderer(private val namespace: INameScope, private val
         module.statements.removeAll(directives)
         module.statements.addAll(0, directives)
 
-        // TODO make sure user-defined blocks come BEFORE library blocks
-
         sortConstantAssignments(module.statements)
     }
 

docs/source/todo.rst

@@ -31,7 +31,6 @@ Add more compiler optimizations to the existing ones.
 - on the final assembly source level
 - can the parameter passing to subroutines be optimized to avoid copying?
 
-- make sure user-defined blocks come BEFORE library blocks (this helps zeropage variable allocations)
 - subroutines with 1 or 2 byte args (or 1 word arg) should be converted to asm calling convention with the args in A/Y register
 
 

examples/test.p8

@@ -4,27 +4,23 @@
 
     sub start() {
 
-        foo(1)
+        myblock2.foo()
-        foo2(20)
+        myblock3.foo()
-        bar(2,3)
-        baz(3333)
-        baz(-3333)
 
     }
-
-    sub foo(ubyte arg) {
-        A=arg
 }
 
-    sub foo2(byte arg) {
+~ myblock2 {
-        A=33
+
+    sub foo() {
+        A=99
+    }
 }
 
-    sub bar(ubyte arg1, ubyte arg2) {
-        A=arg1
-    }
 
-    sub baz(word arg) {
+~ myblock3 {
-        A=lsb(arg)
+
+    sub foo() {
+        A=99
     }
 }

prog8.iml

@@ -11,6 +11,7 @@
       <excludeFolder url="file://$MODULE_DIR$/.gradle" />
       <excludeFolder url="file://$MODULE_DIR$/.idea" />
       <excludeFolder url="file://$MODULE_DIR$/build" />
+      <excludeFolder url="file://$MODULE_DIR$/docs/build" />
       <excludeFolder url="file://$MODULE_DIR$/gradle" />
       <excludeFolder url="file://$MODULE_DIR$/out" />
     </content>