[turbofan] Remove obsolte value input to {Throw} nodes.

Nodes having the {Throw} operator are just used as terminators for
control-flow leaving the function body with an exception completion,
they turn into basic-block terminators within the schedule. Actually
raising an exception is done solely via runtime calls. Hence {Throw}
nodes no longer need any value input.

R=bmeurer@chromium.org

Change-Id: Id6d8e46b12c4b84f4e7a8ac96623c8efb1f27b26
Reviewed-on: https://chromium-review.googlesource.com/446501
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#43445}

src/compiler/ast-graph-builder.cc

@@ -2700,7 +2700,7 @@ Node* AstGraphBuilder::BuildThrowError(Node* exception, BailoutId bailout_id) {
   const Operator* op = javascript()->CallRuntime(Runtime::kThrow);
   Node* call = NewNode(op, exception);
   PrepareFrameState(call, bailout_id);
-  Node* control = NewNode(common()->Throw(), call);
+  Node* control = NewNode(common()->Throw());
   UpdateControlDependencyToLeaveFunction(control);
   return call;
 }
@@ -2712,7 +2712,7 @@ Node* AstGraphBuilder::BuildThrowReferenceError(Variable* variable,
   const Operator* op = javascript()->CallRuntime(Runtime::kThrowReferenceError);
   Node* call = NewNode(op, variable_name);
   PrepareFrameState(call, bailout_id);
-  Node* control = NewNode(common()->Throw(), call);
+  Node* control = NewNode(common()->Throw());
   UpdateControlDependencyToLeaveFunction(control);
   return call;
 }
@@ -2723,7 +2723,7 @@ Node* AstGraphBuilder::BuildThrowConstAssignError(BailoutId bailout_id) {
       javascript()->CallRuntime(Runtime::kThrowConstAssignError);
   Node* call = NewNode(op);
   PrepareFrameState(call, bailout_id);
-  Node* control = NewNode(common()->Throw(), call);
+  Node* control = NewNode(common()->Throw());
   UpdateControlDependencyToLeaveFunction(control);
   return call;
 }
@@ -2744,7 +2744,7 @@ Node* AstGraphBuilder::BuildReturn(Node* return_value) {
 
 Node* AstGraphBuilder::BuildThrow(Node* exception_value) {
   NewNode(javascript()->CallRuntime(Runtime::kReThrow), exception_value);
-  Node* control = NewNode(common()->Throw(), exception_value);
+  Node* control = NewNode(common()->Throw());
   UpdateControlDependencyToLeaveFunction(control);
   return control;
 }

src/compiler/bytecode-graph-builder.cc

@@ -1499,15 +1499,15 @@ void BytecodeGraphBuilder::VisitThrow() {
   Node* value = environment()->LookupAccumulator();
   Node* call = NewNode(javascript()->CallRuntime(Runtime::kThrow), value);
   environment()->BindAccumulator(call, Environment::kAttachFrameState);
-  Node* control = NewNode(common()->Throw(), call);
+  Node* control = NewNode(common()->Throw());
   MergeControlToLeaveFunction(control);
 }
 
 void BytecodeGraphBuilder::VisitReThrow() {
   BuildLoopExitsForFunctionExit();
   Node* value = environment()->LookupAccumulator();
-  Node* call = NewNode(javascript()->CallRuntime(Runtime::kReThrow), value);
-  Node* control = NewNode(common()->Throw(), call);
+  NewNode(javascript()->CallRuntime(Runtime::kReThrow), value);
+  Node* control = NewNode(common()->Throw());
   MergeControlToLeaveFunction(control);
 }
 

src/compiler/common-operator.cc

@@ -354,7 +354,7 @@ ZoneVector<MachineType> const* MachineTypesOf(Operator const* op) {
   V(IfSuccess, Operator::kKontrol, 0, 0, 1, 0, 0, 1)                          \
   V(IfException, Operator::kKontrol, 0, 1, 1, 1, 1, 1)                        \
   V(IfDefault, Operator::kKontrol, 0, 0, 1, 0, 0, 1)                          \
-  V(Throw, Operator::kKontrol, 1, 1, 1, 0, 0, 1)                              \
+  V(Throw, Operator::kKontrol, 0, 1, 1, 0, 0, 1)                              \
   V(Terminate, Operator::kKontrol, 0, 1, 1, 0, 0, 1)                          \
   V(OsrNormalEntry, Operator::kFoldable, 0, 1, 1, 0, 1, 1)                    \
   V(OsrLoopEntry, Operator::kFoldable | Operator::kNoThrow, 0, 1, 1, 0, 1, 1) \

src/compiler/instruction-selector.cc

@@ -982,7 +982,7 @@ void InstructionSelector::VisitControl(BasicBlock* block) {
     }
     case BasicBlock::kThrow:
       DCHECK_EQ(IrOpcode::kThrow, input->opcode());
-      return VisitThrow(input->InputAt(0));
+      return VisitThrow(input);
     case BasicBlock::kNone: {
       // Exit block doesn't have control.
       DCHECK_NULL(input);
@@ -2562,8 +2562,7 @@ void InstructionSelector::VisitDeoptimize(DeoptimizeKind kind,
   EmitDeoptimize(kArchDeoptimize, 0, nullptr, 0, nullptr, kind, reason, value);
 }
 
-
-void InstructionSelector::VisitThrow(Node* value) {
+void InstructionSelector::VisitThrow(Node* node) {
   OperandGenerator g(this);
   Emit(kArchThrowTerminator, g.NoOutput());
 }

src/compiler/instruction-selector.h

@@ -365,7 +365,7 @@ class V8_EXPORT_PRIVATE InstructionSelector final {
   void VisitDeoptimize(DeoptimizeKind kind, DeoptimizeReason reason,
                        Node* value);
   void VisitReturn(Node* ret);
-  void VisitThrow(Node* value);
+  void VisitThrow(Node* node);
   void VisitRetain(Node* node);
 
   void EmitPrepareArguments(ZoneVector<compiler::PushParameter>* arguments,

src/compiler/js-typed-lowering.cc

@@ -714,7 +714,7 @@ Reduction JSTypedLowering::ReduceCreateConsString(Node* node) {
           javascript()->CallRuntime(Runtime::kThrowInvalidStringLength),
           context, frame_state, efalse, if_false);
       if_false = graph()->NewNode(common()->IfSuccess(), vfalse);
-      if_false = graph()->NewNode(common()->Throw(), vfalse, efalse, if_false);
+      if_false = graph()->NewNode(common()->Throw(), efalse, if_false);
       // TODO(bmeurer): This should be on the AdvancedReducer somehow.
       NodeProperties::MergeControlToEnd(graph(), common(), if_false);
       Revisit(graph()->end());

src/compiler/machine-graph-verifier.cc

@@ -521,8 +521,6 @@ class MachineRepresentationChecker {
             break;
           }
           case IrOpcode::kThrow:
-            CheckValueInputIsTagged(node, 0);
-            break;
           case IrOpcode::kTypedStateValues:
           case IrOpcode::kFrameState:
             break;

src/compiler/raw-machine-assembler.cc

@@ -167,8 +167,7 @@ void RawMachineAssembler::PopAndReturn(Node* pop, Node* v1, Node* v2,
 void RawMachineAssembler::DebugBreak() { AddNode(machine()->DebugBreak()); }
 
 void RawMachineAssembler::Unreachable() {
-  Node* values[] = {UndefinedConstant()};  // Unused.
-  Node* ret = MakeNode(common()->Throw(), 1, values);
+  Node* ret = MakeNode(common()->Throw(), 0, nullptr);
   schedule()->AddThrow(CurrentBlock(), ret);
   current_block_ = nullptr;
 }

src/compiler/wasm-compiler.cc

@@ -347,8 +347,7 @@ class WasmTrapHelper : public ZoneObject {
     if (false) {
       // End the control flow with a throw
       Node* thrw =
-          graph()->NewNode(common()->Throw(), jsgraph()->ZeroConstant(),
-                           *effect_ptr, *control_ptr);
+          graph()->NewNode(common()->Throw(), *effect_ptr, *control_ptr);
       MergeControlToEnd(jsgraph(), thrw);
     } else {
       // End the control flow with returning 0xdeadbeef

test/unittests/compiler/common-operator-unittest.cc

@@ -52,7 +52,7 @@ const SharedOperator kSharedOperators[] = {
     SHARED(IfFalse, Operator::kKontrol, 0, 0, 1, 0, 0, 1),
     SHARED(IfSuccess, Operator::kKontrol, 0, 0, 1, 0, 0, 1),
     SHARED(IfException, Operator::kKontrol, 0, 1, 1, 1, 1, 1),
-    SHARED(Throw, Operator::kKontrol, 1, 1, 1, 0, 0, 1),
+    SHARED(Throw, Operator::kKontrol, 0, 1, 1, 0, 0, 1),
     SHARED(Terminate, Operator::kKontrol, 0, 1, 1, 0, 0, 1)
 #undef SHARED
 };