[codegen][debug info] use single compile unit for compilation

backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/BitcodePhases.kt

@@ -18,6 +18,7 @@ import org.jetbrains.kotlin.ir.IrStatement
 import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.util.*
 import org.jetbrains.kotlin.ir.visitors.*
+import org.jetbrains.kotlin.konan.file.File
 import org.jetbrains.kotlin.util.OperatorNameConventions
 
 internal val contextLLVMSetupPhase = makeKonanModuleOpPhase(
@@ -33,6 +34,17 @@ internal val contextLLVMSetupPhase = makeKonanModuleOpPhase(
             val llvmModule = LLVMModuleCreateWithNameInContext("out", llvmContext)!!
             context.llvmModule = llvmModule
             context.debugInfo.builder = LLVMCreateDIBuilder(llvmModule)
+
+            context.debugInfo.compilationUnit = if (context.shouldContainLocationDebugInfo()) DICreateCompilationUnit(
+                    builder = context.debugInfo.builder,
+                    lang = DWARF.language(context.config),
+                    File = File(context.config.outputFile).absolutePath,
+                    dir = "-",
+                    producer = DWARF.producer,
+                    isOptimized = 0,
+                    flags = "",
+                    rv = DWARF.runtimeVersion(context.config)) as DIScopeOpaqueRef?
+            else null
         }
 )
 

backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/DebugUtils.kt

@@ -66,6 +66,7 @@ internal class DebugInfo internal constructor(override val context: Context):Con
     val inlinedSubprograms = mutableMapOf<IrFunction, DISubprogramRef>()
     var builder: DIBuilderRef? = null
     var module: DIModuleRef? = null
+    var compilationUnit: DIScopeOpaqueRef? = null
     var objHeaderPointerType: DITypeOpaqueRef? = null
     var types = mutableMapOf<IrType, DITypeOpaqueRef>()
 

backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/IrToBitcode.kt

@@ -504,20 +504,8 @@ internal class CodeGeneratorVisitor(val context: Context, val lifetimes: Map<IrE
         context.llvm.objects.clear()
         context.llvm.sharedObjects.clear()
 
-        val compilationUnit = if (context.shouldContainLocationDebugInfo()) {
-            val path = declaration.fileEntry.name.toFileAndFolder()
-            DICreateCompilationUnit(
-                    builder = context.debugInfo.builder,
-                    lang = DWARF.language(context.config),
-                    File = path.file,
-                    dir = path.folder,
-                    producer = DWARF.producer,
-                    isOptimized = 0,
-                    flags = "",
-                    rv = DWARF.runtimeVersion(context.config))
-        } else null
         @Suppress("UNCHECKED_CAST")
-        using(FileScope(declaration, compilationUnit as DIScopeOpaqueRef?)) {
+        using(FileScope(declaration)) {
             declaration.acceptChildrenVoid(this)
 
             if (context.llvm.fileInitializers.isEmpty() && context.llvm.objects.isEmpty() && context.llvm.sharedObjects.isEmpty())
@@ -1768,7 +1756,7 @@ internal class CodeGeneratorVisitor(val context: Context, val lifetimes: Map<IrE
 
     //-------------------------------------------------------------------------//
 
-    private open inner class FileScope(val file: IrFile, private val compilationUnit: DIScopeOpaqueRef? = null) : InnerScopeImpl() {
+    private open inner class FileScope(val file: IrFile) : InnerScopeImpl() {
         override fun fileScope(): CodeContext? = this
 
         override fun location(line: Int, column: Int) = scope()?.let { LocationInfo(it, line, column) }
@@ -1781,10 +1769,6 @@ internal class CodeGeneratorVisitor(val context: Context, val lifetimes: Map<IrE
         }
 
         override fun scope() = scope
-        fun diCompilationUnit(): DIScopeOpaqueRef? = compilationUnit ?:
-          (this.outerContext.fileScope() as? FileScope)?.diCompilationUnit() ?:
-            error("no compilation unit found")
-
     }
 
     //-------------------------------------------------------------------------//
@@ -1988,7 +1972,7 @@ internal class CodeGeneratorVisitor(val context: Context, val lifetimes: Map<IrE
     @Suppress("UNCHECKED_CAST")
     private fun diFunctionScope(name: String, linkageName: String, startLine: Int, subroutineType: DISubroutineTypeRef) = DICreateFunction(
                 builder = context.debugInfo.builder,
-                scope = (currentCodeContext.fileScope() as FileScope).diCompilationUnit(),
+                scope = context.debugInfo.compilationUnit,
                 name = name,
                 linkageName = linkageName,
                 file = file().file(),