From fa21a260b1dbd2019c6a7853bb1872b078edf07e Mon Sep 17 00:00:00 2001
From: Igor Chevdar <igor.chevdar@jetbrains.com>
Date: Wed, 4 Oct 2017 17:14:33 +0300
Subject: [PATCH] Fixed coroutines for wasm

Replaced llvm indirectBr instruction with switch instruction.
---
 .../kotlin/backend/konan/KonanConfig.kt       |  2 ++
 .../backend/konan/llvm/CodeGenerator.kt       |  8 +++++
 .../kotlin/backend/konan/llvm/IrToBitcode.kt  | 32 ++++++++++++++-----
 backend.native/tests/build.gradle             | 26 ---------------
 4 files changed, 34 insertions(+), 34 deletions(-)

diff --git a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/KonanConfig.kt b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/KonanConfig.kt
index 082a4205900..0fba27135e9 100644
--- a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/KonanConfig.kt
+++ b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/KonanConfig.kt
@@ -46,6 +46,8 @@ class KonanConfig(val project: Project, val configuration: CompilerConfiguration
     internal val targetManager = TargetManager(
         configuration.get(KonanConfigKeys.TARGET))
 
+    val indirectBranchesAreAllowed = targetManager.target != KonanTarget.WASM32
+
     init {
         val target = targetManager.target
         if (!target.enabled) {
diff --git a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/CodeGenerator.kt b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/CodeGenerator.kt
index 8a7ede5912d..a0f81b99a9a 100644
--- a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/CodeGenerator.kt
+++ b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/CodeGenerator.kt
@@ -461,6 +461,14 @@ internal class FunctionGenerationContext(val function: LLVMValueRef,
         currentPositionHolder.setAfterTerminator()
         return indirectBr
     }
+
+    fun switch(value: LLVMValueRef, cases: Collection<Pair<LLVMValueRef, LLVMBasicBlockRef>>, elseBB: LLVMBasicBlockRef): LLVMValueRef? {
+        val switch = LLVMBuildSwitch(builder, value, elseBB, cases.size)
+        cases.forEach { LLVMAddCase(switch, it.first, it.second) }
+        currentPositionHolder.setAfterTerminator()
+        return switch
+    }
+
     fun resetDebugLocation() {
         if (!context.shouldContainDebugInfo()) return
         if (!currentPositionHolder.isAfterTerminator)
diff --git a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/IrToBitcode.kt b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/IrToBitcode.kt
index 3102d642468..c1862bd3dc9 100644
--- a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/IrToBitcode.kt
+++ b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/IrToBitcode.kt
@@ -189,7 +189,7 @@ internal interface CodeContext {
      */
     fun classScope(): CodeContext?
 
-    fun addResumePoint(bbLabel: LLVMBasicBlockRef)
+    fun addResumePoint(bbLabel: LLVMBasicBlockRef): Int
 }
 
 //-------------------------------------------------------------------------//
@@ -1747,8 +1747,10 @@ internal class CodeGeneratorVisitor(val context: Context, val lifetimes: Map<IrE
     //-------------------------------------------------------------------------//
 
     private inner class SuspendableExpressionScope(val resumePoints: MutableList<LLVMBasicBlockRef>) : InnerScopeImpl() {
-        override fun addResumePoint(bbLabel: LLVMBasicBlockRef) {
+        override fun addResumePoint(bbLabel: LLVMBasicBlockRef): Int {
+            val result = resumePoints.size
             resumePoints.add(bbLabel)
+            return result
         }
     }
 
@@ -1765,26 +1767,40 @@ internal class CodeGeneratorVisitor(val context: Context, val lifetimes: Map<IrE
             val result = evaluateExpression(expression.result)
 
             functionGenerationContext.appendingTo(bbDispatch) {
-                functionGenerationContext.indirectBr(suspensionPointId, resumePoints)
+                if (context.config.indirectBranchesAreAllowed)
+                    functionGenerationContext.indirectBr(suspensionPointId, resumePoints)
+                else {
+                    val bbElse = functionGenerationContext.basicBlock("else", null) {
+                        functionGenerationContext.unreachable()
+                    }
+
+                    val cases = resumePoints.withIndex().map { Int32(it.index + 1).llvm to it.value }
+                    functionGenerationContext.switch(functionGenerationContext.ptrToInt(suspensionPointId, int32Type), cases, bbElse)
+                }
             }
             return result
         }
     }
 
     private inner class SuspensionPointScope(val suspensionPointId: VariableDescriptor,
-                                             val bbResume: LLVMBasicBlockRef): InnerScopeImpl() {
+                                             val bbResume: LLVMBasicBlockRef,
+                                             val bbResumeId: Int): InnerScopeImpl() {
         override fun genGetValue(descriptor: ValueDescriptor): LLVMValueRef {
-            if (descriptor == suspensionPointId)
-                return functionGenerationContext.blockAddress(bbResume)
+            if (descriptor == suspensionPointId) {
+                return if (context.config.indirectBranchesAreAllowed)
+                           functionGenerationContext.blockAddress(bbResume)
+                       else
+                           functionGenerationContext.intToPtr(Int32(bbResumeId + 1).llvm, int8TypePtr)
+            }
             return super.genGetValue(descriptor)
         }
     }
 
     private fun evaluateSuspensionPoint(expression: IrSuspensionPoint): LLVMValueRef {
         val bbResume = functionGenerationContext.basicBlock("resume", expression.resumeResult.startLocation)
-        currentCodeContext.addResumePoint(bbResume)
+        val id = currentCodeContext.addResumePoint(bbResume)
 
-        using (SuspensionPointScope(expression.suspensionPointIdParameter.descriptor, bbResume)) {
+        using (SuspensionPointScope(expression.suspensionPointIdParameter.descriptor, bbResume, id)) {
             continuationBlock(expression.type, expression.result.startLocation).run {
                 val normalResult = evaluateExpression(expression.result)
                 jump(this, normalResult)
diff --git a/backend.native/tests/build.gradle b/backend.native/tests/build.gradle
index 2f8f4368f83..4c2b110bbcf 100644
--- a/backend.native/tests/build.gradle
+++ b/backend.native/tests/build.gradle
@@ -350,7 +350,6 @@ task codegen_controlflow_for_loops_nested(type: RunKonanTest) {
 }
 
 task codegen_controlflow_for_loops_coroutines(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     source = "codegen/controlflow/for_loops_coroutines.kt"
     goldValue = "before: 0 after: 0\n" +
             "before: 2 after: 2\n" +
@@ -938,151 +937,126 @@ task kclass1(type: RunKonanTest) {
 }
 
 task coroutines_simple(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     goldValue = "42\n"
     source = "codegen/coroutines/simple.kt"
 }
 
 task coroutines_degenerate1(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     goldValue = "s1\n"
     source = "codegen/coroutines/degenerate1.kt"
 }
 
 task coroutines_degenerate2(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     goldValue = "s2\ns1\n"
     source = "codegen/coroutines/degenerate2.kt"
 }
 
 task coroutines_withReceiver(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     goldValue = "42\n"
     source = "codegen/coroutines/withReceiver.kt"
 }
 
 task coroutines_correctOrder1(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     goldValue = "f1\ns1\nf2\n160\n"
     source = "codegen/coroutines/correctOrder1.kt"
 }
 
 task coroutines_controlFlow_if1(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     goldValue = "f1\ns1\nf3\n84\n"
     source = "codegen/coroutines/controlFlow_if1.kt"
 }
 
 task coroutines_controlFlow_if2(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     goldValue = "f1\ns1\nf2\n43\n"
     source = "codegen/coroutines/controlFlow_if2.kt"
 }
 
 task coroutines_controlFlow_finally1(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     goldValue = "f1\ns1\n117\n"
     source = "codegen/coroutines/controlFlow_finally1.kt"
 }
 
 task coroutines_controlFlow_finally2(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     goldValue = "f1\ns1\n117\n"
     source = "codegen/coroutines/controlFlow_finally2.kt"
 }
 
 task coroutines_controlFlow_finally3(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     goldValue = "f1\ns1\n117\n"
     source = "codegen/coroutines/controlFlow_finally3.kt"
 }
 
 task coroutines_controlFlow_finally4(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     goldValue = "s1\nfinally\n42\n"
     source = "codegen/coroutines/controlFlow_finally4.kt"
 }
 
 task coroutines_controlFlow_finally5(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     goldValue = "s1\nf2\nfinally\n1\n"
     source = "codegen/coroutines/controlFlow_finally5.kt"
 }
 
 task coroutines_controlFlow_finally6(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     goldValue = "s1\nfinally\nerror\n0\n"
     source = "codegen/coroutines/controlFlow_finally6.kt"
 }
 
 task coroutines_controlFlow_finally7(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     goldValue = "s1\nf2\nfinally1\ns2\nfinally2\n42\n"
     source = "codegen/coroutines/controlFlow_finally7.kt"
 }
 
 task coroutines_controlFlow_inline1(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     goldValue = "42\n"
     source = "codegen/coroutines/controlFlow_inline1.kt"
 }
 
 task coroutines_controlFlow_inline2(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     goldValue = "s1\n42\n"
     source = "codegen/coroutines/controlFlow_inline2.kt"
 }
 
 task coroutines_controlFlow_inline3(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     goldValue = "f1\ns1\n42\n"
     source = "codegen/coroutines/controlFlow_inline3.kt"
 }
 
 task coroutines_controlFlow_tryCatch1(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     goldValue = "s1\n42\n"
     source = "codegen/coroutines/controlFlow_tryCatch1.kt"
 }
 
 task coroutines_controlFlow_tryCatch2(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     goldValue = "s1\n42\n"
     source = "codegen/coroutines/controlFlow_tryCatch2.kt"
 }
 
 task coroutines_controlFlow_tryCatch3(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     goldValue = "s2\nf2\n1\n"
     source = "codegen/coroutines/controlFlow_tryCatch3.kt"
 }
 
 task coroutines_controlFlow_tryCatch4(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     goldValue = "s2\nf2\n1\n"
     source = "codegen/coroutines/controlFlow_tryCatch4.kt"
 }
 
 task coroutines_controlFlow_tryCatch5(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     goldValue = "s2\ns1\nError\n42\n"
     source = "codegen/coroutines/controlFlow_tryCatch5.kt"
 }
 
 task coroutines_controlFlow_while1(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     goldValue = "s3\ns3\ns3\ns3\n3\n"
     source = "codegen/coroutines/controlFlow_while1.kt"
 }
 
 task coroutines_controlFlow_while2(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     goldValue = "s3\ns3\ns3\n3\n"
     source = "codegen/coroutines/controlFlow_while2.kt"
 }
 
 task coroutines_returnsUnit1(type: RunKonanTest) {
-    disabled = (project.testTarget == 'wasm32') // llvm: 'WebAssembly hasn't implemented computed gotos'
     goldValue = "117\ns1\n0\n"
     source = "codegen/coroutines/returnsUnit1.kt"
 }