[turbofan] Introduce new JSConstructWithArrayLike operator.

src/builtins/arm/builtins-arm.cc

Index: src/builtins/arm/builtins-arm.cc
diff --git a/src/builtins/arm/builtins-arm.cc b/src/builtins/arm/builtins-arm.cc
index 1433c9c7038e77f5bce461f41df6b209d03b0fe4..c47a430d736046bba62d7e18d395c5883e2c9e45 100644
--- a/src/builtins/arm/builtins-arm.cc
+++ b/src/builtins/arm/builtins-arm.cc
@@ -2070,39 +2070,17 @@ void Builtins::Generate_ReflectConstruct(MacroAssembler* masm) {
   //  -- sp[0] : receiver (undefined)
   // -----------------------------------
 
-  // 2. Make sure the target is actually a constructor.
-  Label target_not_constructor;
-  __ JumpIfSmi(r1, &target_not_constructor);
-  __ ldr(r4, FieldMemOperand(r1, HeapObject::kMapOffset));
-  __ ldrb(r4, FieldMemOperand(r4, Map::kBitFieldOffset));
-  __ tst(r4, Operand(1 << Map::kIsConstructor));
-  __ b(eq, &target_not_constructor);
+  // 2. We don't need to check explicitly for constructor target here,
+  // since that's the first thing the Construct/ConstructWithArrayLike
+  // builtins will do.
 
-  // 3. Make sure the target is actually a constructor.
-  Label new_target_not_constructor;
-  __ JumpIfSmi(r3, &new_target_not_constructor);
-  __ ldr(r4, FieldMemOperand(r3, HeapObject::kMapOffset));
-  __ ldrb(r4, FieldMemOperand(r4, Map::kBitFieldOffset));
-  __ tst(r4, Operand(1 << Map::kIsConstructor));
-  __ b(eq, &new_target_not_constructor);
+  // 3. We don't need to check explicitly for constructor new.target here,
+  // since that's the second thing the Construct/ConstructWithArrayLike
+  // builtins will do.
 
-  // 4a. Construct the target with the given new.target and argumentsList.
+  // 4. Construct the target with the given new.target and argumentsList.
   __ Jump(masm->isolate()->builtins()->ConstructWithArrayLike(),
           RelocInfo::CODE_TARGET);
-
-  // 4b. The target is not a constructor, throw an appropriate TypeError.
-  __ bind(&target_not_constructor);
-  {
-    __ str(r1, MemOperand(sp, 0));
-    __ TailCallRuntime(Runtime::kThrowNotConstructor);
-  }
-
-  // 4c. The new.target is not a constructor, throw an appropriate TypeError.
-  __ bind(&new_target_not_constructor);
-  {
-    __ str(r3, MemOperand(sp, 0));
-    __ TailCallRuntime(Runtime::kThrowNotConstructor);
-  }
 }
 
 static void EnterArgumentsAdaptorFrame(MacroAssembler* masm) {