[WASM] Fast load string literals from data section

compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/WasmSymbols.kt

@@ -168,6 +168,7 @@ class WasmSymbols(
     val refTest = getInternalFunction("wasm_ref_test")
     val refCast = getInternalFunction("wasm_ref_cast")
     val wasmArrayCopy = getInternalFunction("wasm_array_copy")
+    val wasmArrayNewData0 = getInternalFunction("array_new_data0")
 
     val intToLong = getInternalFunction("wasm_i64_extend_i32_s")
 

compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/ir2wasm/BodyGenerator.kt

@@ -491,6 +491,13 @@ class BodyGenerator(
                 body.buildInstr(WasmOp.ARRAY_COPY, immediate, immediate)
             }
 
+            wasmSymbols.wasmArrayNewData0 -> {
+                val immediate = WasmImmediate.GcType(
+                    context.referenceGcType(call.getTypeArgument(0)!!.getRuntimeClass(irBuiltIns).symbol)
+                )
+                body.buildInstr(WasmOp.ARRAY_NEW_DATA, immediate, WasmImmediate.DataIdx(0))
+            }
+
             wasmSymbols.stringGetPoolSize -> {
                 body.buildConstI32Symbol(context.stringPoolSize)
             }

compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/ir2wasm/DeclarationGenerator.kt

@@ -492,7 +492,6 @@ fun generateConstExpression(expression: IrConst<*>, body: WasmExpressionBuilder,
             body.buildConstI32Symbol(literalPoolId)
             body.buildConstI32Symbol(literalAddress)
             body.buildConstI32(stringValue.length)
-            body.buildConstI32(stringValue.hashCode())
             body.buildCall(context.referenceFunction(context.backendContext.wasmSymbols.stringGetLiteral))
         }
         else -> error("Unknown constant kind")

compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/ir2wasm/WasmCompiledModuleFragment.kt

@@ -124,19 +124,6 @@ class WasmCompiledModuleFragment(val irBuiltIns: IrBuiltIns) {
             currentDataSectionAddress += typeInfoElement.sizeInBytes
         }
 
-        val stringDataSectionStart = currentDataSectionAddress
-        val stringDataSectionBytes = mutableListOf<Byte>()
-        var stringLiteralCount = 0
-        for ((string, symbol) in stringLiteralAddress.unbound) {
-            val constData = ConstantDataCharArray("string_literal", string.toCharArray())
-            stringDataSectionBytes += constData.toBytes().toList()
-            symbol.bind(currentDataSectionAddress)
-            stringLiteralPoolId.reference(string).bind(stringLiteralCount)
-            currentDataSectionAddress += constData.sizeInBytes
-            stringLiteralCount++
-        }
-        stringPoolSize.bind(stringLiteralCount)
-
         // Reserve some memory to pass complex exported types (like strings). It's going to be accessible through 'unsafeGetScratchRawMemory'
         // runtime call from stdlib.
         currentDataSectionAddress = alignUp(currentDataSectionAddress, INT_SIZE_BYTES)
@@ -146,8 +133,22 @@ class WasmCompiledModuleFragment(val irBuiltIns: IrBuiltIns) {
         bind(classIds.unbound, klassIds)
         interfaceId.unbound.onEachIndexed { index, entry -> entry.value.bind(index) }
 
-        val data = typeInfo.buildData(address = { klassIds.getValue(it) }) +
-                WasmData(WasmDataMode.Active(0, stringDataSectionStart), stringDataSectionBytes.toByteArray())
+        val stringDataSectionBytes = mutableListOf<Byte>()
+        var stringDataSectionStart = 0
+        var stringLiteralCount = 0
+        for ((string, symbol) in stringLiteralAddress.unbound) {
+            symbol.bind(stringDataSectionStart)
+            stringLiteralPoolId.reference(string).bind(stringLiteralCount)
+            val constData = ConstantDataCharArray("string_literal", string.toCharArray())
+            stringDataSectionBytes += constData.toBytes().toList()
+            stringDataSectionStart += constData.sizeInBytes
+            stringLiteralCount++
+        }
+        stringPoolSize.bind(stringLiteralCount)
+
+        val data = mutableListOf<WasmData>()
+        data.add(WasmData(WasmDataMode.Passive, stringDataSectionBytes.toByteArray()))
+        typeInfo.buildData(data, address = { klassIds.getValue(it) })
 
         val masterInitFunctionType = WasmFunctionType(emptyList(), emptyList())
         val masterInitFunction = WasmFunction.Defined("__init", WasmSymbol(masterInitFunctionType))
@@ -227,8 +228,11 @@ private fun irSymbolDebugDump(symbol: Any?): String =
         else -> symbol.toString()
     }
 
-inline fun WasmCompiledModuleFragment.ReferencableAndDefinable<IrClassSymbol, ConstantDataElement>.buildData(address: (IrClassSymbol) -> Int): List<WasmData> {
-    return elements.map {
+inline fun WasmCompiledModuleFragment.ReferencableAndDefinable<IrClassSymbol, ConstantDataElement>.buildData(
+    into: MutableList<WasmData>,
+    address: (IrClassSymbol) -> Int
+) {
+    elements.mapTo(into) {
         val id = address(wasmToIr.getValue(it))
         val offset = mutableListOf<WasmInstr>()
         WasmIrExpressionBuilder(offset).buildConstI32(id)