[Wasm] specialize versions of stringLiteral

Author: alex28sh

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

@@ -223,7 +223,8 @@ class WasmSymbols(
     val boxIntrinsic: IrSimpleFunctionSymbol = getInternalFunction("boxIntrinsic")
     val unboxIntrinsic: IrSimpleFunctionSymbol = getInternalFunction("unboxIntrinsic")
 
-    val stringGetLiteral = getFunction("stringLiteral", StandardNames.BUILT_INS_PACKAGE_FQ_NAME)
+    val stringGetLiteralUTF16 = getFunction("stringLiteralUTF16", StandardNames.BUILT_INS_PACKAGE_FQ_NAME)
+    val stringGetLiteralLatin = getFunction("stringLiteralLatin", StandardNames.BUILT_INS_PACKAGE_FQ_NAME)
     val stringGetPoolSize = getInternalFunction("stringGetPoolSize")
 
     val testFun = maybeGetFunction("test", kotlinTestPackageFqName)

compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/dce/WasmUsefulDeclarationProcessor.kt

@@ -32,8 +32,15 @@ internal class WasmUsefulDeclarationProcessor(
     override val bodyVisitor: BodyVisitorBase = object : BodyVisitorBase() {
         override fun visitConst(expression: IrConst, data: IrDeclaration) = when (expression.kind) {
             is IrConstKind.Null -> expression.type.enqueueType(data, "expression type")
-            is IrConstKind.String -> context.wasmSymbols.stringGetLiteral.owner
-                .enqueue(data, "String literal intrinsic getter stringGetLiteral")
+            is IrConstKind.String -> {
+                if ((expression.value as String).all { it.code in 0..255 }) {
+                    context.wasmSymbols.stringGetLiteralLatin.owner
+                        .enqueue(data, "String literal intrinsic getter stringGetLiteral")
+                } else {
+                    context.wasmSymbols.stringGetLiteralUTF16.owner
+                        .enqueue(data, "String literal intrinsic getter stringGetLiteral")
+                }
+            }
             else -> Unit
         }
 

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

@@ -628,8 +628,11 @@ fun generateConstExpression(
             body.buildConstI32Symbol(literalPoolId, location)
             body.buildConstI32Symbol(literalAddress, location)
             body.buildConstI32(stringValue.length, location)
-            body.buildConstI32(if (isLatin) 1 else 0, location)
-            body.buildCall(context.referenceFunction(backendContext.wasmSymbols.stringGetLiteral), location)
+            if (isLatin) {
+                body.buildCall(context.referenceFunction(backendContext.wasmSymbols.stringGetLiteralLatin), location)
+            } else {
+                body.buildCall(context.referenceFunction(backendContext.wasmSymbols.stringGetLiteralUTF16), location)
+            }
             body.commentGroupEnd()
         }
     }

libraries/stdlib/wasm/builtins/kotlin/String.kt

@@ -157,24 +157,32 @@ public actual class String internal @WasmPrimitiveConstructor constructor(
 internal inline fun WasmCharArray.createString(): String =
     String(null, this.len(), this)
 
-internal fun stringLiteral(poolId: Int, startAddress: Int, length: Int, isLatin: Int = 0): String {
+internal fun stringLiteralUTF16(poolId: Int, startAddress: Int, length: Int): String {
     val cached = stringPool[poolId]
     if (cached !== null) {
         return cached
     }
 
-    val chars: WasmCharArray
-    if (isLatin == 0) {
-        chars = array_new_data0<WasmCharArray>(startAddress, length)
-    } else {
-        val bytes = array_new_data0<WasmByteArray>(startAddress, length)
-        chars = WasmCharArray(length)
-        for (i in 0..<length) {
-            val chr = bytes.get(i).toInt().toChar()
-            chars.set(i, chr)
-        }
-    }
+    val chars = array_new_data0<WasmCharArray>(startAddress, length)
     val newString = String(null, length, chars)
     stringPool[poolId] = newString
     return newString
 }
+
+internal fun stringLiteralLatin(poolId: Int, startAddress: Int, length: Int): String {
+    val cached = stringPool[poolId]
+    if (cached !== null) {
+        return cached
+    }
+
+    val bytes = array_new_data0<WasmByteArray>(startAddress, length)
+    val chars = WasmCharArray(length)
+    for (i in 0..<length) {
+        val chr = bytes.get(i).toInt().toChar()
+        chars.set(i, chr)
+    }
+
+    val newString = String(null, length, chars)
+    stringPool[poolId] = newString
+    return newString
+}

libraries/stdlib/wasm/internal/kotlin/wasm/internal/TypeInfo.kt

@@ -56,13 +56,13 @@ internal fun getQualifiedName(rtti: kotlin.wasm.internal.reftypes.structref): St
     return if (packageName.isEmpty()) typeName else "$packageName.$typeName"
 }
 
-internal fun getPackageName(rtti: kotlin.wasm.internal.reftypes.structref): String = stringLiteral(
+internal fun getPackageName(rtti: kotlin.wasm.internal.reftypes.structref): String = stringLiteralUTF16(
     startAddress = wasmGetRttiIntField(2, rtti),
     length = wasmGetRttiIntField(3, rtti),
     poolId = wasmGetRttiIntField(4, rtti),
 )
 
-internal fun getSimpleName(rtti: kotlin.wasm.internal.reftypes.structref): String = stringLiteral(
+internal fun getSimpleName(rtti: kotlin.wasm.internal.reftypes.structref): String = stringLiteralUTF16(
     startAddress = wasmGetRttiIntField(5, rtti),
     length = wasmGetRttiIntField(6, rtti),
     poolId = wasmGetRttiIntField(7, rtti),