[turbofan] Make throwing expressions kill the environment.

This ensures that all expressions that throw actually mark the current
environment as dead in the AstGraphBuilder. This prevents live ranges
from being unnecessarily increased by paths that don't fall-through.
Note that we can do that because Runtime::kThrowFoo never returns.

R=svenpanne@chromium.org

Review URL: https://codereview.chromium.org/1049203002

Cr-Commit-Position: refs/heads/master@{#27546}

src/compiler/ast-graph-builder.cc

@@ -2737,13 +2737,8 @@ Node* AstGraphBuilder::BuildThrowIfStaticPrototype(Node* name,
   Node* check = NewNode(javascript()->StrictEqual(), name, prototype_string);
   prototype_check.If(check);
   prototype_check.Then();
-  {
-    const Operator* op =
-        javascript()->CallRuntime(Runtime::kThrowStaticPrototypeError, 0);
-    Node* call = NewNode(op);
-    PrepareFrameState(call, bailout_id);
-    environment()->Push(call);
-  }
+  Node* error = BuildThrowStaticPrototypeError(bailout_id);
+  environment()->Push(error);
   prototype_check.Else();
   environment()->Push(name);
   prototype_check.End();
@@ -3102,7 +3097,9 @@ Node* AstGraphBuilder::BuildThrowError(Node* exception, BailoutId bailout_id) {
   const Operator* op = javascript()->CallRuntime(Runtime::kThrow, 1);
   Node* call = NewNode(op, exception);
   PrepareFrameState(call, bailout_id);
-  return call;
+  Node* control = NewNode(common()->Throw(), call);
+  UpdateControlDependencyToLeaveFunction(control);
+  return control;
 }
 
 
@@ -3113,7 +3110,9 @@ Node* AstGraphBuilder::BuildThrowReferenceError(Variable* variable,
       javascript()->CallRuntime(Runtime::kThrowReferenceError, 1);
   Node* call = NewNode(op, variable_name);
   PrepareFrameState(call, bailout_id);
-  return call;
+  Node* control = NewNode(common()->Throw(), call);
+  UpdateControlDependencyToLeaveFunction(control);
+  return control;
 }
 
 
@@ -3122,7 +3121,20 @@ Node* AstGraphBuilder::BuildThrowConstAssignError(BailoutId bailout_id) {
       javascript()->CallRuntime(Runtime::kThrowConstAssignError, 0);
   Node* call = NewNode(op);
   PrepareFrameState(call, bailout_id);
-  return call;
+  Node* control = NewNode(common()->Throw(), call);
+  UpdateControlDependencyToLeaveFunction(control);
+  return control;
+}
+
+
+Node* AstGraphBuilder::BuildThrowStaticPrototypeError(BailoutId bailout_id) {
+  const Operator* op =
+      javascript()->CallRuntime(Runtime::kThrowStaticPrototypeError, 0);
+  Node* call = NewNode(op);
+  PrepareFrameState(call, bailout_id);
+  Node* control = NewNode(common()->Throw(), call);
+  UpdateControlDependencyToLeaveFunction(control);
+  return control;
 }
 
 

src/compiler/ast-graph-builder.h

@@ -300,6 +300,7 @@ class AstGraphBuilder : public AstVisitor {
   Node* BuildThrowError(Node* exception, BailoutId bailout_id);
   Node* BuildThrowReferenceError(Variable* var, BailoutId bailout_id);
   Node* BuildThrowConstAssignError(BailoutId bailout_id);
+  Node* BuildThrowStaticPrototypeError(BailoutId bailout_id);
 
   // Builders for dynamic hole-checks at runtime.
   Node* BuildHoleCheckSilent(Node* value, Node* for_hole, Node* not_hole);