[JS IR] Move isPure check to backend.common and add platform-specific check on calls with side effects

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/CommonBackendContext.kt

@@ -12,6 +12,7 @@ import org.jetbrains.kotlin.ir.builders.IrBuilderWithScope
 import org.jetbrains.kotlin.ir.builders.irCall
 import org.jetbrains.kotlin.ir.builders.irString
 import org.jetbrains.kotlin.ir.declarations.IrFile
+import org.jetbrains.kotlin.ir.expressions.IrCall
 import org.jetbrains.kotlin.ir.expressions.IrExpression
 import org.jetbrains.kotlin.ir.symbols.IrClassSymbol
 import org.jetbrains.kotlin.ir.symbols.IrFileSymbol
@@ -45,4 +46,8 @@ interface CommonBackendContext : BackendContext, LoggingContext {
         classSymbolMap: MutableMap<IrClassSymbol, IrClassSymbol>,
         functionSymbolMap: MutableMap<IrSimpleFunctionSymbol, IrSimpleFunctionSymbol>
     ) {}
+
+    fun isSideEffectFree(call: IrCall): Boolean {
+        return false
+    }
 }

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/ir/IrUtils.kt

@@ -644,3 +644,42 @@ private fun computeAllOverridden(function: IrSimpleFunction, result: MutableSet<
         }
     }
 }
+
+// TODO: support more cases like built-in operator call and so on
+fun IrExpression?.isPure(
+    anyVariable: Boolean,
+    checkFields: Boolean = true,
+    context: CommonBackendContext? = null
+): Boolean {
+    if (this == null) return true
+
+    fun IrExpression.isPureImpl(): Boolean {
+        return when (this) {
+            is IrConst<*> -> true
+            is IrGetValue -> {
+                if (anyVariable) return true
+                val valueDeclaration = symbol.owner
+                if (valueDeclaration is IrVariable) !valueDeclaration.isVar
+                else true
+            }
+            is IrCall -> context?.isSideEffectFree(this) ?: false
+            is IrGetObjectValue -> type.isUnit()
+            else -> false
+        }
+    }
+
+    if (isPureImpl()) return true
+
+    if (!checkFields) return false
+
+    if (this is IrGetField) {
+        if (!symbol.owner.isFinal) {
+            if (!anyVariable) {
+                return false
+            }
+        }
+        return receiver.isPure(anyVariable)
+    }
+
+    return false
+}

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/optimizations/PropertyAccessorInlineLowering.kt

@@ -19,7 +19,7 @@ import org.jetbrains.kotlin.ir.expressions.impl.IrGetFieldImpl
 import org.jetbrains.kotlin.ir.expressions.impl.IrSetFieldImpl
 import org.jetbrains.kotlin.ir.util.deepCopyWithSymbols
 import org.jetbrains.kotlin.ir.util.isEffectivelyExternal
-import org.jetbrains.kotlin.ir.util.isPure
+import org.jetbrains.kotlin.backend.common.ir.isPure
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformerVoid
 import org.jetbrains.kotlin.ir.visitors.transformChildrenVoid