From 483f313eda626d91d20f77fdf976eff9d22a6511 Mon Sep 17 00:00:00 2001
From: Irmen de Jong <irmen@razorvine.net>
Date: Thu, 24 Nov 2022 01:19:15 +0100
Subject: [PATCH] ir: keep correct child node order in blocks

---
 .../prog8/codegen/intermediate/IRCodeGen.kt   | 19 ++++---------------
 docs/source/todo.rst                          |  3 +--
 2 files changed, 5 insertions(+), 17 deletions(-)

diff --git a/codeGenIntermediate/src/prog8/codegen/intermediate/IRCodeGen.kt b/codeGenIntermediate/src/prog8/codegen/intermediate/IRCodeGen.kt
index b2179599e..56463e496 100644
--- a/codeGenIntermediate/src/prog8/codegen/intermediate/IRCodeGen.kt
+++ b/codeGenIntermediate/src/prog8/codegen/intermediate/IRCodeGen.kt
@@ -180,14 +180,12 @@ class IRCodeGen(
     private fun flattenNestedSubroutines() {
         // this moves all nested subroutines up to the block scope.
         // also changes the name to be the fully scoped one, so it becomes unique at the top level.
-        // also moves the start() entrypoint as first subroutine.
         val flattenedSubs = mutableListOf<Pair<PtBlock, PtSub>>()
         val flattenedAsmSubs = mutableListOf<Pair<PtBlock, PtAsmSub>>()
         val removalsSubs = mutableListOf<Pair<PtSub, PtSub>>()
         val removalsAsmSubs = mutableListOf<Pair<PtSub, PtAsmSub>>()
         val renameSubs = mutableListOf<Pair<PtBlock, PtSub>>()
         val renameAsmSubs = mutableListOf<Pair<PtBlock, PtAsmSub>>()
-        val entrypoint = program.entrypoint()
 
         fun flattenNestedAsmSub(block: PtBlock, parentSub: PtSub, asmsub: PtAsmSub) {
             val flattened = PtAsmSub(asmsub.scopedName.joinToString("."),
@@ -236,17 +234,8 @@ class IRCodeGen(
         renameSubs.forEach { (parent, sub) ->
             val renamedSub = PtSub(sub.scopedName.joinToString("."), sub.parameters, sub.returntype, sub.inline, sub.position)
             sub.children.forEach { renamedSub.add(it) }
-            parent.children.remove(sub)
-            if (sub === entrypoint) {
-                // entrypoint sub must be first sub
-                val firstsub = parent.children.withIndex().firstOrNull() { it.value is PtSub || it.value is PtAsmSub }
-                if(firstsub!=null)
-                    parent.add(firstsub.index, renamedSub)
-                else
-                    parent.add(renamedSub)
-            } else {
-                parent.add(renamedSub)
-            }
+            val subindex = parent.children.indexOf(sub)
+            parent.children[subindex] = renamedSub      // keep the order of nodes the same
         }
         renameAsmSubs.forEach { (parent, sub) ->
             val renamedSub = PtAsmSub(sub.scopedName.joinToString("."),
@@ -260,8 +249,8 @@ class IRCodeGen(
 
             if(sub.children.isNotEmpty())
                 renamedSub.add(sub.children.single())
-            parent.children.remove(sub)
-            parent.add(renamedSub)
+            val subindex = parent.children.indexOf(sub)
+            parent.children[subindex] = renamedSub       // keep the order of nodes the same
         }
     }
 
diff --git a/docs/source/todo.rst b/docs/source/todo.rst
index 26fd3468e..37cde05f5 100644
--- a/docs/source/todo.rst
+++ b/docs/source/todo.rst
@@ -3,9 +3,8 @@ TODO
 
 For next release
 ^^^^^^^^^^^^^^^^
-- ir/vm: check weird asm chunks appearing in block?
 - try to get the cx16 adpcm example to output audio
-- duplicate diskio for cx16 (get rid of cx16diskio, just copy diskio and tweak everything)
+- duplicate diskio for cx16 (get rid of cx16diskio, just copy diskio and tweak everything) + documentation
 - get f_seek_w working like in the BASIC program  - this needs the changes to diskio.f_open to use suffixes ,p,m
 - attempt to fix the expression codegen bug with reused temp vars (github #89)
 - AstIdentifiersChecker: can a subroutine really not have the same name as its enclosing block? 64tass problem?