From 73a86fffe5eac6d64b9887deedcdd2b58e35847d Mon Sep 17 00:00:00 2001
From: Igor Yakovlev <igor.yakovlev@jetbrains.com>
Date: Fri, 22 Apr 2022 16:44:05 +0200
Subject: [PATCH] [WASM] Bootstrap std compatibility fix

---
 .../kotlin/backend/wasm/WasmSymbols.kt        |  2 +-
 .../backend/wasm/ir2wasm/BodyGenerator.kt     |  2 +-
 .../wasm/lower/WasmTypeOperatorLowering.kt    |  2 +-
 .../internal/kotlin/wasm/internal/TypeInfo.kt | 50 ++++++++++++++++++-
 4 files changed, 51 insertions(+), 5 deletions(-)

diff --git a/compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/WasmSymbols.kt b/compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/WasmSymbols.kt
index a7ca8cc596c..36417c8b7b3 100644
--- a/compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/WasmSymbols.kt
+++ b/compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/WasmSymbols.kt
@@ -173,7 +173,7 @@ class WasmSymbols(
     val wasmClassId = getInternalFunction("wasmClassId")
     val wasmInterfaceId = getInternalFunction("wasmInterfaceId")
 
-    val isInterface = getInternalFunction("isInterface")
+    val wasmIsInterface = getInternalFunction("wasmIsInterface")
 
     val nullableEquals = getInternalFunction("nullableEquals")
     val ensureNotNull = getInternalFunction("ensureNotNull")
diff --git a/compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/ir2wasm/BodyGenerator.kt b/compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/ir2wasm/BodyGenerator.kt
index 53614c0b91a..7af7a2494a6 100644
--- a/compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/ir2wasm/BodyGenerator.kt
+++ b/compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/ir2wasm/BodyGenerator.kt
@@ -402,7 +402,7 @@ class BodyGenerator(
                 body.buildConstI32Symbol(context.referenceInterfaceId(irInterface.symbol))
             }
 
-            wasmSymbols.isInterface -> {
+            wasmSymbols.wasmIsInterface -> {
                 val irInterface = call.getTypeArgument(0)!!.getClass()
                     ?: error("No interface given for wasmInterfaceId intrinsic")
                 assert(irInterface.isInterface)
diff --git a/compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/lower/WasmTypeOperatorLowering.kt b/compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/lower/WasmTypeOperatorLowering.kt
index 81320f363bf..7ecece22efe 100644
--- a/compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/lower/WasmTypeOperatorLowering.kt
+++ b/compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/lower/WasmTypeOperatorLowering.kt
@@ -300,7 +300,7 @@ class WasmBaseTypeOperatorTransformer(val context: WasmBackendContext) : IrEleme
     }
 
     private fun generateIsInterface(argument: IrExpression, toType: IrType): IrExpression {
-        return builder.irCall(symbols.isInterface).apply {
+        return builder.irCall(symbols.wasmIsInterface).apply {
             putValueArgument(0, argument)
             putTypeArgument(0, toType)
         }
diff --git a/libraries/stdlib/wasm/internal/kotlin/wasm/internal/TypeInfo.kt b/libraries/stdlib/wasm/internal/kotlin/wasm/internal/TypeInfo.kt
index b4005e2b4a3..ff01f74195b 100644
--- a/libraries/stdlib/wasm/internal/kotlin/wasm/internal/TypeInfo.kt
+++ b/libraries/stdlib/wasm/internal/kotlin/wasm/internal/TypeInfo.kt
@@ -48,7 +48,7 @@ internal fun isInterfaceById(obj: Any, interfaceId: Int): Boolean {
 }
 
 @ExcludedFromCodegen
-internal fun <T> isInterface(obj: Any): Boolean =
+internal fun <T> wasmIsInterface(obj: Any): Boolean =
     implementedAsIntrinsic
 
 @ExcludedFromCodegen
@@ -61,4 +61,50 @@ internal fun <T> wasmInterfaceId(): Int =
 
 @ExcludedFromCodegen
 internal fun <T> wasmGetTypeInfoData(): TypeInfoData =
-    implementedAsIntrinsic
\ No newline at end of file
+    implementedAsIntrinsic
+
+
+//REMOVE AFTER COMPILER BOOTSTRAP
+internal const val TYPE_INFO_ITABLE_PTR_OFFSET = TYPE_INFO_SUPER_TYPE_OFFSET + TYPE_INFO_ELEMENT_SIZE
+internal const val TYPE_INFO_VTABLE_LENGTH_OFFSET = TYPE_INFO_ITABLE_PTR_OFFSET + TYPE_INFO_ELEMENT_SIZE
+internal const val TYPE_INFO_VTABLE_OFFSET = TYPE_INFO_VTABLE_LENGTH_OFFSET + TYPE_INFO_ELEMENT_SIZE
+
+internal fun getVtablePtr(obj: Any): Int =
+    obj.typeInfo + TYPE_INFO_VTABLE_OFFSET
+
+internal fun getVtableLength(obj: Any): Int =
+    wasm_i32_load(obj.typeInfo + TYPE_INFO_VTABLE_LENGTH_OFFSET)
+
+internal fun getItablePtr(obj: Any): Int =
+    wasm_i32_load(obj.typeInfo + TYPE_INFO_ITABLE_PTR_OFFSET)
+
+internal fun getInterfaceListLength(itablePtr: Int): Int =
+    wasm_i32_load(itablePtr + TYPE_INFO_VTABLE_LENGTH_OFFSET)
+
+internal fun getVirtualMethodId(obj: Any, virtualFunctionSlot: Int): Int {
+    val vtablePtr = getVtablePtr(obj)
+    val methodIdPtr = vtablePtr + virtualFunctionSlot * TYPE_INFO_ELEMENT_SIZE
+    return wasm_i32_load(methodIdPtr)
+}
+
+// Returns -1 if obj does not implement interface
+internal fun getInterfaceImplId(obj: Any, interfaceId: Int): Int {
+    val interfaceListSizePtr = getItablePtr(obj)
+    val interfaceListPtr = interfaceListSizePtr + TYPE_INFO_ELEMENT_SIZE
+    val interfaceListSize = wasm_i32_load(interfaceListSizePtr)
+
+    var interfaceSlot = 0
+    while (interfaceSlot < interfaceListSize) {
+        val supportedInterface = wasm_i32_load(interfaceListPtr + interfaceSlot * TYPE_INFO_ELEMENT_SIZE)
+        if (supportedInterface == interfaceId) {
+            return wasm_i32_load(interfaceListPtr + interfaceListSize * TYPE_INFO_ELEMENT_SIZE + interfaceSlot * TYPE_INFO_ELEMENT_SIZE)
+        }
+        interfaceSlot++
+    }
+
+    return -1
+}
+
+internal fun isInterface(obj: Any, interfaceId: Int): Boolean {
+    return getInterfaceImplId(obj, interfaceId) != -1
+}
\ No newline at end of file