Version 2.2.23...

src/x64/codegen-x64.cc

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 3355 matching lines @@
         expression->AsLiteral()->IsNull())) {
       // Omit evaluating the value of the primitive literal.
       // It will be discarded anyway, and can have no side effect.
       frame_->Push(Factory::undefined_value());
     } else {
       Load(node->expression());
       frame_->SetElementAt(0, Factory::undefined_value());
     }
 
   } else {
-    bool overwrite =
+    bool can_overwrite =
       (node->expression()->AsBinaryOperation() != NULL &&
        node->expression()->AsBinaryOperation()->ResultOverwriteAllowed());
+    UnaryOverwriteMode overwrite =
+        can_overwrite ? UNARY_OVERWRITE : UNARY_NO_OVERWRITE;
+    bool no_negative_zero = node->expression()->no_negative_zero();
     Load(node->expression());
     switch (op) {
       case Token::NOT:
       case Token::DELETE:
       case Token::TYPEOF:
         UNREACHABLE();  // handled above
         break;
 
       case Token::SUB: {
-        GenericUnaryOpStub stub(Token::SUB, overwrite);
+        GenericUnaryOpStub stub(
+            Token::SUB,
+            overwrite,
+            no_negative_zero ? kIgnoreNegativeZero : kStrictNegativeZero);
         Result operand = frame_->Pop();
         Result answer = frame_->CallStub(&stub, &operand);
         answer.set_type_info(TypeInfo::Number());
         frame_->Push(&answer);
         break;
       }
 
       case Token::BIT_NOT: {
         // Smi check.
         JumpTarget smi_label;
@@ skipping 5100 matching lines @@
 
 
 void GenericUnaryOpStub::Generate(MacroAssembler* masm) {
   Label slow, done;
 
   if (op_ == Token::SUB) {
     // Check whether the value is a smi.
     Label try_float;
     __ JumpIfNotSmi(rax, &try_float);
 
+    if (negative_zero_ == kIgnoreNegativeZero) {
+      __ SmiCompare(rax, Smi::FromInt(0));
+      __ j(equal, &done);
+    }
+
     // Enter runtime system if the value of the smi is zero
     // to make sure that we switch between 0 and -0.
     // Also enter it if the value of the smi is Smi::kMinValue.
     __ SmiNeg(rax, rax, &done);
 
     // Either zero or Smi::kMinValue, neither of which become a smi when
     // negated.
-    __ SmiCompare(rax, Smi::FromInt(0));
-    __ j(not_equal, &slow);
-    __ Move(rax, Factory::minus_zero_value());
-    __ jmp(&done);
+    if (negative_zero_ == kStrictNegativeZero) {
+      __ SmiCompare(rax, Smi::FromInt(0));
+      __ j(not_equal, &slow);
+      __ Move(rax, Factory::minus_zero_value());
+      __ jmp(&done);
+    } else  {
+      __ jmp(&slow);
+    }
 
     // Try floating point case.
     __ bind(&try_float);
     __ movq(rdx, FieldOperand(rax, HeapObject::kMapOffset));
     __ CompareRoot(rdx, Heap::kHeapNumberMapRootIndex);
     __ j(not_equal, &slow);
     // Operand is a float, negate its value by flipping sign bit.
     __ movq(rdx, FieldOperand(rax, HeapNumber::kValueOffset));
     __ movq(kScratchRegister, Immediate(0x01));
     __ shl(kScratchRegister, Immediate(63));
     __ xor_(rdx, kScratchRegister);  // Flip sign.
     // rdx is value to store.
-    if (overwrite_) {
+    if (overwrite_ == UNARY_OVERWRITE) {
       __ movq(FieldOperand(rax, HeapNumber::kValueOffset), rdx);
     } else {
       __ AllocateHeapNumber(rcx, rbx, &slow);
       // rcx: allocated 'empty' number
       __ movq(FieldOperand(rcx, HeapNumber::kValueOffset), rdx);
       __ movq(rax, rcx);
     }
   } else if (op_ == Token::BIT_NOT) {
     // Check if the operand is a heap number.
     __ movq(rdx, FieldOperand(rax, HeapObject::kMapOffset));
@@ skipping 2046 matching lines @@
       case Token::MUL:
       case Token::DIV: {
         if (runtime_operands_type_ == BinaryOpIC::DEFAULT &&
             HasSmiCodeInStub()) {
           // Execution reaches this point when the first non-smi argument occurs
           // (and only if smi code is generated). This is the right moment to
           // patch to HEAP_NUMBERS state. The transition is attempted only for
           // the four basic operations. The stub stays in the DEFAULT state
           // forever for all other operations (also if smi code is skipped).
           GenerateTypeTransition(masm);
+          break;
         }
 
         Label not_floats;
         // rax: y
         // rdx: x
         if (static_operands_type_.IsNumber()) {
           if (FLAG_debug_code) {
             // Assert at runtime that inputs are only numbers.
             __ AbortIfNotNumber(rdx);
             __ AbortIfNotNumber(rax);
@@ skipping 297 matching lines @@
     __ push(rdx);
     __ push(rax);
   }
   __ push(rcx);
 }
 
 
 void GenericBinaryOpStub::GenerateTypeTransition(MacroAssembler* masm) {
   Label get_result;
 
-  // Keep a copy of operands on the stack and make sure they are also in
-  // rdx, rax.
+  // Ensure the operands are on the stack.
   if (HasArgsInRegisters()) {
     GenerateRegisterArgsPush(masm);
-  } else {
-    GenerateLoadArguments(masm);
   }
 
-  // Internal frame is necessary to handle exceptions properly.
-  __ EnterInternalFrame();
-
-  // Push arguments on stack if the stub expects them there.
-  if (!HasArgsInRegisters()) {
-    __ push(rdx);
-    __ push(rax);
-  }
-  // Call the stub proper to get the result in rax.
-  __ call(&get_result);
-  __ LeaveInternalFrame();
-
   // Left and right arguments are already on stack.
-  __ pop(rcx);
-  // Push the operation result. The tail call to BinaryOp_Patch will
-  // return it to the original caller..
-  __ push(rax);
+  __ pop(rcx);  // Save the return address.
 
   // Push this stub's key.
   __ Push(Smi::FromInt(MinorKey()));
 
   // Although the operation and the type info are encoded into the key,
   // the encoding is opaque, so push them too.
   __ Push(Smi::FromInt(op_));
 
   __ Push(Smi::FromInt(runtime_operands_type_));
 
-  __ push(rcx);
+  __ push(rcx);  // The return address.
 
   // Perform patching to an appropriate fast case and return the result.
   __ TailCallExternalReference(
       ExternalReference(IC_Utility(IC::kBinaryOp_Patch)),
-      6,
+      5,
       1);
-
-  // The entry point for the result calculation is assumed to be immediately
-  // after this sequence.
-  __ bind(&get_result);
 }
 
 
 Handle<Code> GetBinaryOpStub(int key, BinaryOpIC::TypeInfo type_info) {
   GenericBinaryOpStub stub(key, type_info);
   return stub.GetCode();
 }
 
 
 int CompareStub::MinorKey() {
@@ skipping 1097 matching lines @@
 }
 
 #endif
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64