[fullcode] Switch passing of new.target to register.

src/full-codegen/ia32/full-codegen-ia32.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #if V8_TARGET_ARCH_IA32
 
 #include "src/ast/scopes.h"
 #include "src/code-factory.h"
 #include "src/code-stubs.h"
 #include "src/codegen.h"
@@ skipping 65 matching lines @@
 };
 
 
 // Generate code for a JS function.  On entry to the function the receiver
 // and arguments have been pushed on the stack left to right, with the
 // return address on top of them.  The actual argument count matches the
 // formal parameter count expected by the function.
 //
 // The live registers are:
 //   o edi: the JS function object being called (i.e. ourselves)
+//   o edx: the new target value
 //   o esi: our context
 //   o ebp: our caller's frame pointer
 //   o esp: stack pointer (pointing to return address)
 //
 // The function builds a JS frame.  Please see JavaScriptFrameConstants in
 // frames-ia32.h for its layout.
 void FullCodeGenerator::Generate() {
   CompilationInfo* info = info_;
   profiling_counter_ = isolate()->factory()->NewCell(
       Handle<Smi>(Smi::FromInt(FLAG_interrupt_budget), isolate()));
@@ skipping 71 matching lines @@
   if (info->scope()->num_heap_slots() > 0) {
     Comment cmnt(masm_, "[ Allocate context");
     bool need_write_barrier = true;
     int slots = info->scope()->num_heap_slots() - Context::MIN_CONTEXT_SLOTS;
     // Argument to NewContext is the function, which is still in edi.
     if (info->scope()->is_script_scope()) {
       __ push(edi);
       __ Push(info->scope()->GetScopeInfo(info->isolate()));
       __ CallRuntime(Runtime::kNewScriptContext, 2);
       PrepareForBailoutForId(BailoutId::ScriptContext(), TOS_REG);
-    } else if (slots <= FastNewContextStub::kMaximumSlots) {
-      FastNewContextStub stub(isolate(), slots);
-      __ CallStub(&stub);
-      // Result of FastNewContextStub is always in new space.
-      need_write_barrier = false;
+      // The new target value is not used, clobbering is safe.
+      DCHECK_NULL(info->scope()->new_target_var());
     } else {
-      __ push(edi);
-      __ CallRuntime(Runtime::kNewFunctionContext, 1);
+      if (info->scope()->new_target_var() != nullptr) {
+        __ push(edx);  // Preserve new target.
+      }
+      if (slots <= FastNewContextStub::kMaximumSlots) {
+        FastNewContextStub stub(isolate(), slots);
+        __ CallStub(&stub);
+        // Result of FastNewContextStub is always in new space.
+        need_write_barrier = false;
+      } else {
+        __ push(edi);
+        __ CallRuntime(Runtime::kNewFunctionContext, 1);
+      }
+      if (info->scope()->new_target_var() != nullptr) {
+        __ pop(edx);  // Restore new target.
+      }
     }
     function_in_register = false;
     // Context is returned in eax.  It replaces the context passed to us.
     // It's saved in the stack and kept live in esi.
     __ mov(esi, eax);
     __ mov(Operand(ebp, StandardFrameConstants::kContextOffset), eax);
 
     // Copy parameters into context if necessary.
     int num_parameters = info->scope()->num_parameters();
     int first_parameter = info->scope()->has_this_declaration() ? -1 : 0;
@@ skipping 16 matching lines @@
                                     kDontSaveFPRegs);
         } else if (FLAG_debug_code) {
           Label done;
           __ JumpIfInNewSpace(esi, eax, &done, Label::kNear);
           __ Abort(kExpectedNewSpaceObject);
           __ bind(&done);
         }
       }
     }
   }
+
+  // Register holding this function and new target are both trashed in case we
+  // bailout here. But since that can happen only when new target is not used
+  // and we allocate a context, the value of |function_in_register| is correct.
   PrepareForBailoutForId(BailoutId::FunctionContext(), NO_REGISTERS);
 
-  // Function register is trashed in case we bailout here. But since that
-  // could happen only when we allocate a context the value of
-  // |function_in_register| is correct.
-
   // Possibly set up a local binding to the this function which is used in
   // derived constructors with super calls.
   Variable* this_function_var = scope()->this_function_var();
   if (this_function_var != nullptr) {
     Comment cmnt(masm_, "[ This function");
     if (!function_in_register) {
       __ mov(edi, Operand(ebp, JavaScriptFrameConstants::kFunctionOffset));
       // The write barrier clobbers register again, keep it marked as such.
     }
-    SetVar(this_function_var, edi, ebx, edx);
+    SetVar(this_function_var, edi, ebx, ecx);
   }
 
+  // Possibly set up a local binding to the new target value.
   Variable* new_target_var = scope()->new_target_var();
   if (new_target_var != nullptr) {
     Comment cmnt(masm_, "[ new.target");
-    __ mov(eax, Operand(ebp, StandardFrameConstants::kCallerFPOffset));
-    Label non_adaptor_frame;
-    __ cmp(Operand(eax, StandardFrameConstants::kContextOffset),
-           Immediate(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
-    __ j(not_equal, &non_adaptor_frame);
-    __ mov(eax, Operand(eax, StandardFrameConstants::kCallerFPOffset));
-
-    __ bind(&non_adaptor_frame);
-    __ cmp(Operand(eax, StandardFrameConstants::kMarkerOffset),
-           Immediate(Smi::FromInt(StackFrame::CONSTRUCT)));
-
-    Label non_construct_frame, done;
-    __ j(not_equal, &non_construct_frame);
-
-    // Construct frame
-    __ mov(eax, Operand(eax, ConstructFrameConstants::kNewTargetOffset));
-    __ jmp(&done);
-
-    // Non-construct frame
-    __ bind(&non_construct_frame);
-    __ mov(eax, Immediate(isolate()->factory()->undefined_value()));
-
-    __ bind(&done);
-    SetVar(new_target_var, eax, ebx, edx);
+    SetVar(new_target_var, edx, ebx, ecx);
   }
 
   Variable* arguments = scope()->arguments();
   if (arguments != NULL) {
     // Function uses arguments object.
     Comment cmnt(masm_, "[ Allocate arguments object");
     DCHECK(edi.is(ArgumentsAccessNewDescriptor::function()));
     if (!function_in_register) {
       __ mov(edi, Operand(ebp, JavaScriptFrameConstants::kFunctionOffset));
     }
@@ skipping 4565 matching lines @@
             Assembler::target_address_at(call_target_address,
                                          unoptimized_code));
   return OSR_AFTER_STACK_CHECK;
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_IA32