Sort inlining requests before creating SMAP

Fixes SMAP generation breaking bytecode idempotency assertions

Author: Kordyjan

compiler/src/dotty/tools/backend/jvm/InlinedSourceMaps.scala

@@ -82,17 +82,16 @@ object InlinedSourceMaps:
   end Stratum
 
   def sourceMapFor(cunit: CompilationUnit)(internalNameProvider: Symbol => String)(using Context): InlinedSourceMap =
-    val requests = mutable.ListBuffer.empty[Request]
-    var lastLine = cunit.tpdTree.sourcePos.endLine
+    val requests = mutable.ListBuffer.empty[(SourcePosition, SourcePosition)]
     var internalNames = Map.empty[SourceFile, String]
 
     class RequestCollector(enclosingFile: SourceFile) extends TreeTraverser:
       override def traverse(tree: Tree)(using Context): Unit =
         if tree.source != enclosingFile && tree.source != cunit.source then
           tree.getAttachment(InliningPosition) match
             case Some(InliningPosition(targetPos, cls)) =>
-              val firstFakeLine = allocate(tree.sourcePos)
-              requests += Request(targetPos, tree.sourcePos, firstFakeLine)
+              requests += (targetPos -> tree.sourcePos)
+
               cls match
                 case Some(symbol) if !internalNames.isDefinedAt(tree.source) =>
                   internalNames += (tree.source -> internalNameProvider(symbol))
@@ -108,13 +107,15 @@ object InlinedSourceMaps:
         else traverseChildren(tree)
     end RequestCollector
 
+    var lastLine = cunit.tpdTree.sourcePos.endLine
     def allocate(origPos: SourcePosition): Int =
       val line = lastLine + 1
       lastLine += origPos.lines.length
       line
 
     RequestCollector(cunit.source).traverse(cunit.tpdTree)
-    InlinedSourceMap(cunit, requests.toList, internalNames)
+    val allocated = requests.sortBy(_._1.start).map(r => Request(r._1, r._2, allocate(r._2)))
+    InlinedSourceMap(cunit, allocated.toList, internalNames)
   end sourceMapFor
 
   class InlinedSourceMap private[InlinedSourceMaps] (

compiler/src/dotty/tools/dotc/typer/Inliner.scala

@@ -230,12 +230,8 @@ object Inliner {
     val topLevelClass = Some(inlined.call.symbol.topLevelClass).filter(_.exists)
     val inliningPosition = InliningPosition(inlined.sourcePos, topLevelClass)
 
-    // In case that bindings are present we are adding InliningPosition attachement both to the resulting block and to the expansion
-    // as in some cases the block is removed in one of later phases and attachment is lost.
-    val tree1 =
-      if inlined.bindings.isEmpty then inlined.expansion
-      else cpy.Block(inlined)(inlined.bindings, inlined.expansion.withAttachment(InliningPosition, inliningPosition))
-    tree1.withAttachment(InliningPosition, inliningPosition)
+    val withPos = inlined.expansion.withAttachment(InliningPosition, inliningPosition)
+    if inlined.bindings.isEmpty then withPos else cpy.Block(inlined)(inlined.bindings, withPos)
 
   /** Leave only a call trace consisting of
    *  - a reference to the top-level class from which the call was inlined,