new classes: implement correct check for uninitialized this in 'super()'

R=arv@chromium.org
BUG=v8:3834
LOG=N

Review URL: https://codereview.chromium.org/918603004

Cr-Commit-Position: refs/heads/master@{#26599}

src/arm/full-codegen-arm.cc

@@ -3270,18 +3270,6 @@ void FullCodeGenerator::EmitSuperConstructorCall(Call* expr) {
   EmitLoadSuperConstructor();
   __ push(result_register());
 
-  SuperReference* super_ref = expr->expression()->AsSuperReference();
-  Variable* this_var = super_ref->this_var()->var();
-
-  GetVar(r0, this_var);
-  __ CompareRoot(r0, Heap::kTheHoleValueRootIndex);
-  Label uninitialized_this;
-  __ b(eq, &uninitialized_this);
-  __ mov(r0, Operand(this_var->name()));
-  __ Push(r0);
-  __ CallRuntime(Runtime::kThrowReferenceError, 1);
-  __ bind(&uninitialized_this);
-
   // Push the arguments ("left-to-right") on the stack.
   ZoneList<Expression*>* args = expr->arguments();
   int arg_count = args->length();
@@ -3317,6 +3305,17 @@ void FullCodeGenerator::EmitSuperConstructorCall(Call* expr) {
 
   RecordJSReturnSite(expr);
 
+  SuperReference* super_ref = expr->expression()->AsSuperReference();
+  Variable* this_var = super_ref->this_var()->var();
+  GetVar(r1, this_var);
+  __ CompareRoot(r1, Heap::kTheHoleValueRootIndex);
+  Label uninitialized_this;
+  __ b(eq, &uninitialized_this);
+  __ mov(r0, Operand(this_var->name()));
+  __ Push(r0);
+  __ CallRuntime(Runtime::kThrowReferenceError, 1);
+  __ bind(&uninitialized_this);
+
   EmitVariableAssignment(this_var, Token::INIT_CONST);
   context()->Plug(r0);
 }

src/arm64/full-codegen-arm64.cc

@@ -2956,20 +2956,9 @@ void FullCodeGenerator::EmitSuperConstructorCall(Call* expr) {
   GetVar(result_register(), new_target_var);
   __ Push(result_register());
 
-  SuperReference* super_ref = expr->expression()->AsSuperReference();
   EmitLoadSuperConstructor();
   __ push(result_register());
 
-  Variable* this_var = super_ref->this_var()->var();
-
-  GetVar(x0, this_var);
-  Label uninitialized_this;
-  __ JumpIfRoot(x0, Heap::kTheHoleValueRootIndex, &uninitialized_this);
-  __ Mov(x0, Operand(this_var->name()));
-  __ Push(x0);
-  __ CallRuntime(Runtime::kThrowReferenceError, 1);
-  __ bind(&uninitialized_this);
-
   // Push the arguments ("left-to-right") on the stack.
   ZoneList<Expression*>* args = expr->arguments();
   int arg_count = args->length();
@@ -3005,6 +2994,16 @@ void FullCodeGenerator::EmitSuperConstructorCall(Call* expr) {
 
   RecordJSReturnSite(expr);
 
+  SuperReference* super_ref = expr->expression()->AsSuperReference();
+  Variable* this_var = super_ref->this_var()->var();
+  GetVar(x1, this_var);
+  Label uninitialized_this;
+  __ JumpIfRoot(x1, Heap::kTheHoleValueRootIndex, &uninitialized_this);
+  __ Mov(x0, Operand(this_var->name()));
+  __ Push(x0);
+  __ CallRuntime(Runtime::kThrowReferenceError, 1);
+  __ bind(&uninitialized_this);
+
   EmitVariableAssignment(this_var, Token::INIT_CONST);
   context()->Plug(x0);
 }

src/ia32/full-codegen-ia32.cc

@@ -3146,19 +3146,9 @@ void FullCodeGenerator::EmitSuperConstructorCall(Call* expr) {
   GetVar(eax, new_target_var);
   __ push(eax);
 
-  SuperReference* super_ref = expr->expression()->AsSuperReference();
   EmitLoadSuperConstructor();
   __ push(result_register());
 
-  Variable* this_var = super_ref->this_var()->var();
-  GetVar(eax, this_var);
-  __ cmp(eax, isolate()->factory()->the_hole_value());
-  Label uninitialized_this;
-  __ j(equal, &uninitialized_this);
-  __ push(Immediate(this_var->name()));
-  __ CallRuntime(Runtime::kThrowReferenceError, 1);
-  __ bind(&uninitialized_this);
-
   // Push the arguments ("left-to-right") on the stack.
   ZoneList<Expression*>* args = expr->arguments();
   int arg_count = args->length();
@@ -3194,6 +3184,16 @@ void FullCodeGenerator::EmitSuperConstructorCall(Call* expr) {
 
   RecordJSReturnSite(expr);
 
+  SuperReference* super_ref = expr->expression()->AsSuperReference();
+  Variable* this_var = super_ref->this_var()->var();
+  GetVar(ecx, this_var);
+  __ cmp(ecx, isolate()->factory()->the_hole_value());
+  Label uninitialized_this;
+  __ j(equal, &uninitialized_this);
+  __ push(Immediate(this_var->name()));
+  __ CallRuntime(Runtime::kThrowReferenceError, 1);
+  __ bind(&uninitialized_this);
+
   EmitVariableAssignment(this_var, Token::INIT_CONST);
   context()->Plug(eax);
 }

src/x64/full-codegen-x64.cc

@@ -3155,18 +3155,6 @@ void FullCodeGenerator::EmitSuperConstructorCall(Call* expr) {
   EmitLoadSuperConstructor();
   __ Push(result_register());
 
-  SuperReference* super_ref = expr->expression()->AsSuperReference();
-  Variable* this_var = super_ref->this_var()->var();
-
-  GetVar(rax, this_var);
-  __ CompareRoot(rax, Heap::kTheHoleValueRootIndex);
-  Label uninitialized_this;
-  __ j(equal, &uninitialized_this);
-  __ Push(this_var->name());
-  __ CallRuntime(Runtime::kThrowReferenceError, 1);
-  __ bind(&uninitialized_this);
-
-
   // Push the arguments ("left-to-right") on the stack.
   ZoneList<Expression*>* args = expr->arguments();
   int arg_count = args->length();
@@ -3195,7 +3183,6 @@ void FullCodeGenerator::EmitSuperConstructorCall(Call* expr) {
   __ Move(rbx, FeedbackVector());
   __ Move(rdx, SmiFromSlot(expr->CallFeedbackSlot()));
 
-  // TODO(dslomov): use a different stub and propagate new.target.
   CallConstructStub stub(isolate(), SUPER_CALL_RECORD_TARGET);
   __ call(stub.GetCode(), RelocInfo::CONSTRUCT_CALL);
 
@@ -3203,6 +3190,15 @@ void FullCodeGenerator::EmitSuperConstructorCall(Call* expr) {
 
   RecordJSReturnSite(expr);
 
+  SuperReference* super_ref = expr->expression()->AsSuperReference();
+  Variable* this_var = super_ref->this_var()->var();
+  GetVar(rcx, this_var);
+  __ CompareRoot(rcx, Heap::kTheHoleValueRootIndex);
+  Label uninitialized_this;
+  __ j(equal, &uninitialized_this);
+  __ Push(this_var->name());
+  __ CallRuntime(Runtime::kThrowReferenceError, 1);
+  __ bind(&uninitialized_this);
 
   EmitVariableAssignment(this_var, Token::INIT_CONST);
   context()->Plug(rax);

test/mjsunit/harmony/classes-experimental.js

@@ -89,8 +89,7 @@
         super(tmp(),4);
       } catch (e) { exn = e; }
       assertTrue(exn instanceof ReferenceError);
-      // TODO(dslomov): should be 'true'.
-      assertFalse(called);
+      assertTrue(called);
     }
   }
 
@@ -110,6 +109,61 @@
   assertThrows(function() { new BadSubclass(); }, ReferenceError);
 }());
 
+(function TestThisCheckOrdering() {
+  let baseCalled = 0;
+  class Base {
+    constructor() { baseCalled++ }
+  }
+
+  let fCalled = 0;
+  function f() { fCalled++; return 3; }
+
+  class Subclass1 extends Base {
+    constructor() {
+      baseCalled = 0;
+      super();
+      assertEquals(1, baseCalled);
+      let obj = this;
+
+      let exn = null;
+      baseCalled = 0;
+      fCalled = 0;
+      try {
+        super(f());
+      } catch (e) { exn = e; }
+      assertTrue(exn instanceof ReferenceError);
+      assertEquals(1, fCalled);
+      assertEquals(1, baseCalled);
+      assertSame(obj, this);
+
+      exn = null;
+      baseCalled = 0;
+      fCalled = 0;
+      try {
+        super(super(), f());
+      } catch (e) { exn = e; }
+      assertTrue(exn instanceof ReferenceError);
+      assertEquals(0, fCalled);
+      assertEquals(1, baseCalled);
+      assertSame(obj, this);
+
+      exn = null;
+      baseCalled = 0;
+      fCalled = 0;
+      try {
+        super(f(), super());
+      } catch (e) { exn = e; }
+      assertTrue(exn instanceof ReferenceError);
+      assertEquals(1, fCalled);
+      assertEquals(1, baseCalled);
+      assertSame(obj, this);
+    }
+  }
+
+  new Subclass1();
+}());
+
+
 (function TestPrototypeWiring() {
   class Base {
     constructor(x) {