backend: Add a call lowering pass before inlining

Some inlined calls may require additional processing before the
inlining pass. E.g. assert() calls must be removed if assertions are
disabled by compiler flags. This patch adds an additional pass
before inlining and uses it for assertions removal.

backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/common/ir/Ir.kt

@@ -14,7 +14,6 @@ import org.jetbrains.kotlin.ir.util.SymbolTable
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.types.KotlinType
-import org.jetbrains.kotlin.types.SimpleType
 import org.jetbrains.kotlin.util.OperatorNameConventions
 
 // This is what Context collects about IR.

backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/KonanLower.kt

@@ -40,6 +40,10 @@ internal class KonanLower(val context: Context) {
     fun lowerModule(irModule: IrModuleFragment) {
         val phaser = PhaseManager(context)
 
+        phaser.phase(KonanPhase.LOWER_SPECIAL_CALLS) {
+            irModule.files.forEach(SpecialCallsLowering(context)::lower)
+        }
+
         phaser.phase(KonanPhase.LOWER_INLINE_CONSTRUCTORS) {
             InlineConstructorsTransformation(context).lower(irModule)
         }

backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/KonanPhases.kt

@@ -28,8 +28,9 @@ enum class KonanPhase(val description: String,
     /* */ SERIALIZER("Serialize descriptor tree and inline IR bodies"),
     /* */ BACKEND("All backend"),
     /* ... */ LOWER("IR Lowering"),
-    /* ... ... */ LOWER_INLINE_CONSTRUCTORS("Inline constructors transformation"),
-    /* ... ... */ LOWER_INLINE("Functions inlining", LOWER_INLINE_CONSTRUCTORS),
+    /* ... ... */ LOWER_SPECIAL_CALLS("Special calls processing before inlining"),
+    /* ... ... */ LOWER_INLINE_CONSTRUCTORS("Inline constructors transformation", LOWER_SPECIAL_CALLS),
+    /* ... ... */ LOWER_INLINE("Functions inlining", LOWER_INLINE_CONSTRUCTORS, LOWER_SPECIAL_CALLS),
     /* ... ... ...  */ DESERIALIZER("Deserialize inline bodies"),
     /* ... ... */ LOWER_INTEROP_PART1("Interop lowering, part 1", LOWER_INLINE),
     /* ... ... */ LOWER_FOR_LOOPS("For loops lowering"),

backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/lower/BuiltinOperatorLowering.kt

@@ -19,23 +19,20 @@ package org.jetbrains.kotlin.backend.konan.lower
 import org.jetbrains.kotlin.backend.common.BodyLoweringPass
 import org.jetbrains.kotlin.backend.common.atMostOne
 import org.jetbrains.kotlin.backend.konan.Context
-import org.jetbrains.kotlin.backend.konan.KonanConfigKeys.Companion.ENABLE_ASSERTIONS
-import org.jetbrains.kotlin.backend.konan.isStdlib
 import org.jetbrains.kotlin.backend.konan.isValueType
 import org.jetbrains.kotlin.ir.descriptors.IrBuiltinOperatorDescriptor
-import org.jetbrains.kotlin.ir.expressions.*
+import org.jetbrains.kotlin.ir.expressions.IrBody
+import org.jetbrains.kotlin.ir.expressions.IrCall
+import org.jetbrains.kotlin.ir.expressions.IrExpression
+import org.jetbrains.kotlin.ir.expressions.IrTypeOperatorCall
 import org.jetbrains.kotlin.ir.expressions.impl.IrCallImpl
-import org.jetbrains.kotlin.ir.expressions.impl.IrCompositeImpl
 import org.jetbrains.kotlin.ir.symbols.IrSimpleFunctionSymbol
 import org.jetbrains.kotlin.ir.util.isNullConst
 import org.jetbrains.kotlin.ir.util.type
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformerVoid
 import org.jetbrains.kotlin.ir.visitors.transformChildrenVoid
-import org.jetbrains.kotlin.resolve.descriptorUtil.fqNameSafe
-import org.jetbrains.kotlin.resolve.descriptorUtil.module
 import org.jetbrains.kotlin.types.typeUtil.isNothing
 import org.jetbrains.kotlin.types.typeUtil.isSubtypeOf
-import org.jetbrains.kotlin.types.typeUtil.isUnit
 
 /**
  * This lowering pass lowers some calls to [IrBuiltinOperatorDescriptor]s.
@@ -54,20 +51,11 @@ private class BuiltinOperatorTransformer(val context: Context) : IrElementTransf
 
     private val builtIns = context.builtIns
     private val irBuiltins = context.irModule!!.irBuiltins
-    private val enableAssertions = context.config.configuration.getBoolean(ENABLE_ASSERTIONS)
-
-    private val assertSymbols = context.ir.symbols.asserts
 
     override fun visitCall(expression: IrCall): IrExpression {
         expression.transformChildrenVoid(this)
         val descriptor = expression.descriptor
 
-        // Replace assert() call with an empty composite if assertions are not enabled.
-        if (!enableAssertions && expression.symbol in assertSymbols) {
-            assert(expression.type.isUnit())
-            return IrCompositeImpl(expression.startOffset, expression.endOffset, expression.type)
-        }
-
         if (descriptor is IrBuiltinOperatorDescriptor) {
             return transformBuiltinOperator(expression)
         }

backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/lower/SpecialCallsLowering.kt

@@ -0,0 +1,39 @@
+package org.jetbrains.kotlin.backend.konan.lower
+
+import org.jetbrains.kotlin.backend.common.FileLoweringPass
+import org.jetbrains.kotlin.backend.konan.Context
+import org.jetbrains.kotlin.backend.konan.KonanConfigKeys
+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.expressions.impl.IrCompositeImpl
+import org.jetbrains.kotlin.ir.visitors.IrElementTransformerVoid
+import org.jetbrains.kotlin.ir.visitors.transformChildrenVoid
+import org.jetbrains.kotlin.types.typeUtil.isUnit
+
+/**
+ * This pass runs before inlining and performs the following additional transformations over some calls:
+ *     - Assertion call removal.
+ */
+internal class SpecialCallsLowering(val context: Context) : FileLoweringPass {
+
+    private val asserts = context.ir.symbols.asserts
+    private val enableAssertions = context.config.configuration.getBoolean(KonanConfigKeys.ENABLE_ASSERTIONS)
+
+    override fun lower(irFile: IrFile) {
+        irFile.transformChildrenVoid(object : IrElementTransformerVoid() {
+
+            override fun visitCall(expression: IrCall): IrExpression {
+                expression.transformChildrenVoid(this)
+
+                // Replace assert() call with an empty composite if assertions are not enabled.
+                if (!enableAssertions && expression.symbol in asserts) {
+                    assert(expression.type.isUnit())
+                    return IrCompositeImpl(expression.startOffset, expression.endOffset, expression.type)
+                }
+
+                return expression
+            }
+        })
+    }
+}