JVM: refactor some SMAP-related classes

In particular, remove redundant copying from SMAPAndMethodNode (which
also fails for empty methods).

compiler/backend/src/org/jetbrains/kotlin/codegen/inline/InlineCodegen.kt

@@ -233,7 +233,7 @@ abstract class InlineCodegen<out T : BaseExpressionCodegen>(
         val inliner = MethodInliner(
             node, parameters, info, FieldRemapper(null, null, parameters), isSameModule,
             "Method inlining " + sourceCompiler.callElementText,
-            createNestedSourceMapper(nodeAndSmap, defaultSourceMapper), info.callSiteInfo,
+            NestedSourceMapper(defaultSourceMapper, nodeAndSmap.classSMAP), info.callSiteInfo,
             if (functionDescriptor.isInlineOnly()) InlineOnlySmapSkipper(codegen) else null,
             !isInlinedToInlineFunInKotlinRuntime()
         ) //with captured
@@ -576,7 +576,7 @@ abstract class InlineCodegen<out T : BaseExpressionCodegen>(
                 result ?: throw IllegalStateException("Couldn't obtain compiled function body for $functionDescriptor")
             }
 
-            return resultInCache.copyWithNewNode(cloneMethodNode(resultInCache.node))
+            return SMAPAndMethodNode(cloneMethodNode(resultInCache.node), resultInCache.classSMAP)
         }
 
         private fun createDefaultFakeSMAP() = SMAPParser.parseOrCreateDefault(null, null, "fake", -1, -1)
@@ -704,11 +704,6 @@ abstract class InlineCodegen<out T : BaseExpressionCodegen>(
             }
             return result
         }
-
-
-        fun createNestedSourceMapper(nodeAndSmap: SMAPAndMethodNode, parent: SourceMapper): SourceMapper {
-            return NestedSourceMapper(parent, nodeAndSmap.sortedRanges, nodeAndSmap.classSMAP.sourceInfo)
-        }
     }
 
 }

compiler/backend/src/org/jetbrains/kotlin/codegen/inline/InlineCodegenForDefaultBody.kt

@@ -42,7 +42,7 @@ class InlineCodegenForDefaultBody(
         val nodeAndSmap = InlineCodegen.createInlineMethodNode(
             function, methodOwner, jvmSignature, callDefault, null, codegen.typeSystem, state, sourceCompilerForInline
         )
-        val childSourceMapper = InlineCodegen.createNestedSourceMapper(nodeAndSmap, sourceMapper)
+        val childSourceMapper = NestedSourceMapper(sourceMapper, nodeAndSmap.classSMAP)
 
         val node = nodeAndSmap.node
         val transformedMethod = MethodNode(

compiler/backend/src/org/jetbrains/kotlin/codegen/inline/MethodInliner.kt

@@ -284,10 +284,11 @@ class MethodInliner(
 
                     val childSourceMapper =
                         if (inliningContext.classRegeneration && !inliningContext.isInliningLambda)
-                            NestedSourceMapper(sourceMapper, lambdaSMAP.intervals, lambdaSMAP.sourceInfo)
-                        else if (info is DefaultLambda) {
-                            NestedSourceMapper(sourceMapper.parent!!, lambdaSMAP.intervals, lambdaSMAP.sourceInfo)
-                        } else InlineLambdaSourceMapper(sourceMapper.parent!!, info.node)
+                            NestedSourceMapper(sourceMapper, lambdaSMAP)
+                        else if (info is DefaultLambda)
+                            NestedSourceMapper(sourceMapper.parent!!, lambdaSMAP)
+                        else
+                            SameFileNestedSourceMapper(sourceMapper.parent!!, info.node.classSMAP)
 
                     val inliner = MethodInliner(
                         info.node.node, lambdaParameters, inliningContext.subInlineLambda(info),

compiler/backend/src/org/jetbrains/kotlin/codegen/inline/SMAP.kt

@@ -13,6 +13,7 @@ import org.jetbrains.kotlin.codegen.inline.SMAP.Companion.FILE_SECTION
 import org.jetbrains.kotlin.codegen.inline.SMAP.Companion.LINE_SECTION
 import org.jetbrains.kotlin.codegen.inline.SMAP.Companion.STRATA_SECTION
 import org.jetbrains.kotlin.load.java.JvmAbi
+import org.jetbrains.org.objectweb.asm.tree.MethodNode
 import java.util.*
 import kotlin.math.max
 
@@ -86,8 +87,8 @@ class SMAPBuilder(
 }
 
 open class NestedSourceMapper(
-    override val parent: SourceMapper, val ranges: List<RangeMapping>, sourceInfo: SourceInfo
-) : DefaultSourceMapper(sourceInfo) {
+    override val parent: SourceMapper, protected val smap: SMAP
+) : DefaultSourceMapper(smap.sourceInfo) {
 
     private val visitedLines = TIntIntHashMap()
 
@@ -104,7 +105,7 @@ open class NestedSourceMapper(
             mappedLineNumber
         } else {
             val rangeForMapping =
-                (if (lastVisitedRange?.contains(lineNumber) == true) lastVisitedRange!! else findMappingIfExists(lineNumber))
+                (if (lastVisitedRange?.contains(lineNumber) == true) lastVisitedRange!! else smap.findRange(lineNumber))
                     ?: error("Can't find range to map line $lineNumber in ${sourceInfo.source}: ${sourceInfo.pathOrCleanFQN}")
             val sourceLineNumber = rangeForMapping.mapDestToSource(lineNumber)
             val newLineNumber = parent.mapLineNumber(sourceLineNumber, rangeForMapping.parent!!.name, rangeForMapping.parent!!.path)
@@ -115,22 +116,12 @@ open class NestedSourceMapper(
             newLineNumber
         }
     }
-
-    private fun findMappingIfExists(lineNumber: Int): RangeMapping? {
-        val index = ranges.binarySearch(RangeMapping(lineNumber, lineNumber, 1), Comparator { value, key ->
-            if (key.dest in value) 0 else RangeMapping.Comparator.compare(value, key)
-        })
-        return if (index < 0) null else ranges[index]
-    }
 }
 
-open class InlineLambdaSourceMapper(
-    parent: SourceMapper, smap: SMAPAndMethodNode
-) : NestedSourceMapper(parent, smap.sortedRanges, smap.classSMAP.sourceInfo) {
-
+open class SameFileNestedSourceMapper(parent: SourceMapper, smap: SMAP) : NestedSourceMapper(parent, smap) {
     override fun mapLineNumber(lineNumber: Int): Int {
-        if (ranges.firstOrNull()?.contains(lineNumber) == true) {
-            //don't remap origin lambda line numbers
+        if (lineNumber <= smap.sourceInfo.linesInFile) {
+            // assuming the parent source mapper is for the same file, this line number does not need remapping
             return lineNumber
         }
         return super.mapLineNumber(lineNumber)
@@ -250,20 +241,20 @@ open class DefaultSourceMapper(val sourceInfo: SourceInfo) : SourceMapper {
 }
 
 class SMAP(val fileMappings: List<FileMapping>) {
-    init {
+    val sourceInfo: SourceInfo = run {
         assert(fileMappings.isNotEmpty()) { "File Mappings shouldn't be empty" }
+        val defaultFile = fileMappings.first()
+        val defaultRange = defaultFile.lineMappings.first()
+        SourceInfo(defaultFile.name, defaultFile.path, defaultRange.source + defaultRange.range - 1)
     }
 
-    val default: FileMapping
-        get() = fileMappings.first()
+    private val intervals = fileMappings.flatMap { it.lineMappings }.sortedWith(RangeMapping.Comparator)
 
-    val intervals = fileMappings.flatMap { it.lineMappings }.sortedWith(RangeMapping.Comparator)
-
-    val sourceInfo: SourceInfo
-
-    init {
-        val defaultMapping = default.lineMappings.first()
-        sourceInfo = SourceInfo(default.name, default.path, defaultMapping.source + defaultMapping.range - 1)
+    fun findRange(lineNumber: Int): RangeMapping? {
+        val index = intervals.binarySearch(RangeMapping(lineNumber, lineNumber, 1), Comparator { value, key ->
+            if (key.dest in value) 0 else RangeMapping.Comparator.compare(value, key)
+        })
+        return if (index < 0) null else intervals[index]
     }
 
     companion object {
@@ -274,6 +265,7 @@ class SMAP(val fileMappings: List<FileMapping>) {
     }
 }
 
+data class SMAPAndMethodNode(val node: MethodNode, val classSMAP: SMAP)
 
 class RawFileMapping(val name: String, val path: String) {
     private val rangeMappings = arrayListOf<RangeMapping>()

compiler/backend/src/org/jetbrains/kotlin/codegen/inline/SMAPAndMethodNode.kt

@@ -1,48 +0,0 @@
-/*
- * Copyright 2010-2015 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package org.jetbrains.kotlin.codegen.inline
-
-import org.jetbrains.kotlin.codegen.optimization.common.InsnSequence
-import org.jetbrains.kotlin.load.java.JvmAbi
-import org.jetbrains.org.objectweb.asm.tree.LineNumberNode
-import org.jetbrains.org.objectweb.asm.tree.MethodNode
-import java.util.*
-
-//TODO comment
-class SMAPAndMethodNode(val node: MethodNode, val classSMAP: SMAP) {
-    val sortedRanges = createLineNumberSequence(node, classSMAP).distinct().toList().sortedWith(RangeMapping.Comparator)
-
-    fun copyWithNewNode(newMethodNode: MethodNode) = SMAPAndMethodNode(newMethodNode, classSMAP)
-}
-
-private fun createLineNumberSequence(node: MethodNode, classSMAP: SMAP): Sequence<RangeMapping> {
-    return InsnSequence(node.instructions.first, null).filterIsInstance<LineNumberNode>().map { lineNumber ->
-        val mapping = RangeMapping(lineNumber.line, lineNumber.line, 1)
-
-        if (lineNumber.line in JvmAbi.SYNTHETIC_MARKER_LINE_NUMBERS) {
-            return@map mapping
-        }
-
-        val index = classSMAP.intervals.binarySearch(mapping, Comparator { value, key ->
-            if (key.dest in value) 0 else RangeMapping.Comparator.compare(value, key)
-        })
-        if (index < 0) {
-            error("Unmapped line number in inlined function ${node.name}:${lineNumber.line}")
-        }
-        classSMAP.intervals[index]
-    }
-}