Version 3.1.7...

src/x64/full-codegen-x64.cc

 // Copyright 2011 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 189 matching lines @@
     // stack frame was an arguments adapter frame.
     ArgumentsAccessStub stub(ArgumentsAccessStub::NEW_OBJECT);
     __ CallStub(&stub);
     // Store new arguments object in both "arguments" and ".arguments" slots.
     __ movq(rcx, rax);
     Move(arguments->AsSlot(), rax, rbx, rdx);
     Slot* dot_arguments_slot = scope()->arguments_shadow()->AsSlot();
     Move(dot_arguments_slot, rcx, rbx, rdx);
   }
 
-  { Comment cmnt(masm_, "[ Declarations");
-    // For named function expressions, declare the function name as a
-    // constant.
-    if (scope()->is_function_scope() && scope()->function() != NULL) {
-      EmitDeclaration(scope()->function(), Variable::CONST, NULL);
-    }
-    // Visit all the explicit declarations unless there is an illegal
-    // redeclaration.
-    if (scope()->HasIllegalRedeclaration()) {
-      scope()->VisitIllegalRedeclaration(this);
-    } else {
-      VisitDeclarations(scope()->declarations());
-    }
-  }
-
   if (FLAG_trace) {
     __ CallRuntime(Runtime::kTraceEnter, 0);
   }
 
-  { Comment cmnt(masm_, "[ Stack check");
-    PrepareForBailout(info->function(), NO_REGISTERS);
-    NearLabel ok;
-    __ CompareRoot(rsp, Heap::kStackLimitRootIndex);
-    __ j(above_equal, &ok);
-    StackCheckStub stub;
-    __ CallStub(&stub);
-    __ bind(&ok);
+  // Visit the declarations and body unless there is an illegal
+  // redeclaration.
+  if (scope()->HasIllegalRedeclaration()) {
+    Comment cmnt(masm_, "[ Declarations");
+    scope()->VisitIllegalRedeclaration(this);
+  } else {
+    { Comment cmnt(masm_, "[ Declarations");
+      // For named function expressions, declare the function name as a
+      // constant.
+      if (scope()->is_function_scope() && scope()->function() != NULL) {
+        EmitDeclaration(scope()->function(), Variable::CONST, NULL);
+      }
+      VisitDeclarations(scope()->declarations());
+    }
+
+    { Comment cmnt(masm_, "[ Stack check");
+      PrepareForBailout(info->function(), NO_REGISTERS);
+      NearLabel ok;
+      __ CompareRoot(rsp, Heap::kStackLimitRootIndex);
+      __ j(above_equal, &ok);
+      StackCheckStub stub;
+      __ CallStub(&stub);
+      __ bind(&ok);
+    }
+
+    { Comment cmnt(masm_, "[ Body");
+      ASSERT(loop_depth() == 0);
+      VisitStatements(function()->body());
+      ASSERT(loop_depth() == 0);
+    }
   }
 
-  { Comment cmnt(masm_, "[ Body");
-    ASSERT(loop_depth() == 0);
-    VisitStatements(function()->body());
-    ASSERT(loop_depth() == 0);
-  }
-
+  // Always emit a 'return undefined' in case control fell off the end of
+  // the body.
   { Comment cmnt(masm_, "[ return <undefined>;");
-    // Emit a 'return undefined' in case control fell off the end of the body.
     __ LoadRoot(rax, Heap::kUndefinedValueRootIndex);
     EmitReturnSequence();
   }
 }
 
 
 void FullCodeGenerator::ClearAccumulator() {
   __ Set(rax, 0);
 }
 
 
 void FullCodeGenerator::EmitStackCheck(IterationStatement* stmt) {
   Comment cmnt(masm_, "[ Stack check");
   NearLabel ok;
   __ CompareRoot(rsp, Heap::kStackLimitRootIndex);
   __ j(above_equal, &ok);
   StackCheckStub stub;
   __ CallStub(&stub);
   // Record a mapping of this PC offset to the OSR id.  This is used to find
   // the AST id from the unoptimized code in order to use it as a key into
   // the deoptimization input data found in the optimized code.
   RecordStackCheck(stmt->OsrEntryId());
 
+  // Loop stack checks can be patched to perform on-stack replacement. In
+  // order to decide whether or not to perform OSR we embed the loop depth
+  // in a test instruction after the call so we can extract it from the OSR
+  // builtin.
+  ASSERT(loop_depth() > 0);
+  __ testl(rax, Immediate(Min(loop_depth(), Code::kMaxLoopNestingMarker)));
+
   __ bind(&ok);
   PrepareForBailoutForId(stmt->EntryId(), NO_REGISTERS);
   // Record a mapping of the OSR id to this PC.  This is used if the OSR
   // entry becomes the target of a bailout.  We don't expect it to be, but
   // we want it to work if it is.
   PrepareForBailoutForId(stmt->OsrEntryId(), NO_REGISTERS);
 }
 
 
 void FullCodeGenerator::EmitReturnSequence() {
@@ skipping 256 matching lines @@
 void FullCodeGenerator::DoTest(Label* if_true,
                                Label* if_false,
                                Label* fall_through) {
   // Emit the inlined tests assumed by the stub.
   __ CompareRoot(result_register(), Heap::kUndefinedValueRootIndex);
   __ j(equal, if_false);
   __ CompareRoot(result_register(), Heap::kTrueValueRootIndex);
   __ j(equal, if_true);
   __ CompareRoot(result_register(), Heap::kFalseValueRootIndex);
   __ j(equal, if_false);
-  ASSERT_EQ(0, kSmiTag);
+  STATIC_ASSERT(kSmiTag == 0);
   __ SmiCompare(result_register(), Smi::FromInt(0));
   __ j(equal, if_false);
   Condition is_smi = masm_->CheckSmi(result_register());
   __ j(is_smi, if_true);
 
   // Call the ToBoolean stub for all other cases.
   ToBooleanStub stub;
   __ push(result_register());
   __ CallStub(&stub);
   __ testq(rax, rax);
@@ skipping 287 matching lines @@
   Label loop, exit;
   ForIn loop_statement(this, stmt);
   increment_loop_depth();
 
   // Get the object to enumerate over. Both SpiderMonkey and JSC
   // ignore null and undefined in contrast to the specification; see
   // ECMA-262 section 12.6.4.
   VisitForAccumulatorValue(stmt->enumerable());
   __ CompareRoot(rax, Heap::kUndefinedValueRootIndex);
   __ j(equal, &exit);
-  __ CompareRoot(rax, Heap::kNullValueRootIndex);
+  Register null_value = rdi;
+  __ LoadRoot(null_value, Heap::kNullValueRootIndex);
+  __ cmpq(rax, null_value);
   __ j(equal, &exit);
 
   // Convert the object to a JS object.
   Label convert, done_convert;
   __ JumpIfSmi(rax, &convert);
   __ CmpObjectType(rax, FIRST_JS_OBJECT_TYPE, rcx);
   __ j(above_equal, &done_convert);
   __ bind(&convert);
   __ push(rax);
   __ InvokeBuiltin(Builtins::TO_OBJECT, CALL_FUNCTION);
   __ bind(&done_convert);
   __ push(rax);
 
-  // BUG(867): Check cache validity in generated code. This is a fast
-  // case for the JSObject::IsSimpleEnum cache validity checks. If we
-  // cannot guarantee cache validity, call the runtime system to check
-  // cache validity or get the property names in a fixed array.
+  // Check cache validity in generated code. This is a fast case for
+  // the JSObject::IsSimpleEnum cache validity checks. If we cannot
+  // guarantee cache validity, call the runtime system to check cache
+  // validity or get the property names in a fixed array.
+  Label next, call_runtime;
+  Register empty_fixed_array_value = r8;
+  __ LoadRoot(empty_fixed_array_value, Heap::kEmptyFixedArrayRootIndex);
+  Register empty_descriptor_array_value = r9;
+  __ LoadRoot(empty_descriptor_array_value,
+              Heap::kEmptyDescriptorArrayRootIndex);
+  __ movq(rcx, rax);
+  __ bind(&next);
+
+  // Check that there are no elements.  Register rcx contains the
+  // current JS object we've reached through the prototype chain.
+  __ cmpq(empty_fixed_array_value,
+          FieldOperand(rcx, JSObject::kElementsOffset));
+  __ j(not_equal, &call_runtime);
+
+  // Check that instance descriptors are not empty so that we can
+  // check for an enum cache.  Leave the map in rbx for the subsequent
+  // prototype load.
+  __ movq(rbx, FieldOperand(rcx, HeapObject::kMapOffset));
+  __ movq(rdx, FieldOperand(rbx, Map::kInstanceDescriptorsOffset));
+  __ cmpq(rdx, empty_descriptor_array_value);
+  __ j(equal, &call_runtime);
+
+  // Check that there is an enum cache in the non-empty instance
+  // descriptors (rdx).  This is the case if the next enumeration
+  // index field does not contain a smi.
+  __ movq(rdx, FieldOperand(rdx, DescriptorArray::kEnumerationIndexOffset));
+  __ JumpIfSmi(rdx, &call_runtime);
+
+  // For all objects but the receiver, check that the cache is empty.
+  NearLabel check_prototype;
+  __ cmpq(rcx, rax);
+  __ j(equal, &check_prototype);
+  __ movq(rdx, FieldOperand(rdx, DescriptorArray::kEnumCacheBridgeCacheOffset));
+  __ cmpq(rdx, empty_fixed_array_value);
+  __ j(not_equal, &call_runtime);
+
+  // Load the prototype from the map and loop if non-null.
+  __ bind(&check_prototype);
+  __ movq(rcx, FieldOperand(rbx, Map::kPrototypeOffset));
+  __ cmpq(rcx, null_value);
+  __ j(not_equal, &next);
+
+  // The enum cache is valid.  Load the map of the object being
+  // iterated over and use the cache for the iteration.
+  NearLabel use_cache;
+  __ movq(rax, FieldOperand(rax, HeapObject::kMapOffset));
+  __ jmp(&use_cache);
 
   // Get the set of properties to enumerate.
+  __ bind(&call_runtime);
   __ push(rax);  // Duplicate the enumerable object on the stack.
   __ CallRuntime(Runtime::kGetPropertyNamesFast, 1);
 
   // If we got a map from the runtime call, we can do a fast
   // modification check. Otherwise, we got a fixed array, and we have
   // to do a slow check.
   NearLabel fixed_array;
   __ CompareRoot(FieldOperand(rax, HeapObject::kMapOffset),
                  Heap::kMetaMapRootIndex);
   __ j(not_equal, &fixed_array);
 
   // We got a map in register rax. Get the enumeration cache from it.
+  __ bind(&use_cache);
   __ movq(rcx, FieldOperand(rax, Map::kInstanceDescriptorsOffset));
   __ movq(rcx, FieldOperand(rcx, DescriptorArray::kEnumerationIndexOffset));
   __ movq(rdx, FieldOperand(rcx, DescriptorArray::kEnumCacheBridgeCacheOffset));
 
   // Setup the four remaining stack slots.
   __ push(rax);  // Map.
   __ push(rdx);  // Enumeration cache.
   __ movq(rax, FieldOperand(rdx, FixedArray::kLengthOffset));
   __ push(rax);  // Enumeration cache length (as smi).
   __ Push(Smi::FromInt(0));  // Initial index.
@@ skipping 68 matching lines @@
 
   // Exit and decrement the loop depth.
   __ bind(&exit);
   decrement_loop_depth();
 }
 
 
 void FullCodeGenerator::EmitNewClosure(Handle<SharedFunctionInfo> info,
                                        bool pretenure) {
   // Use the fast case closure allocation code that allocates in new
-  // space for nested functions that don't need literals cloning.
-  if (scope()->is_function_scope() &&
+  // space for nested functions that don't need literals cloning. If
+  // we're running with the --always-opt or the --prepare-always-opt
+  // flag, we need to use the runtime function so that the new function
+  // we are creating here gets a chance to have its code optimized and
+  // doesn't just get a copy of the existing unoptimized code.
+  if (!FLAG_always_opt &&
+      !FLAG_prepare_always_opt &&
+      scope()->is_function_scope() &&
       info->num_literals() == 0 &&
       !pretenure) {
     FastNewClosureStub stub;
     __ Push(info);
     __ CallStub(&stub);
   } else {
     __ push(rsi);
     __ Push(info);
     __ Push(pretenure ? Factory::true_value() : Factory::false_value());
     __ CallRuntime(Runtime::kNewClosure, 3);
@@ skipping 89 matching lines @@
       }
       __ movq(temp, ContextOperand(context, Context::CLOSURE_INDEX));
       __ movq(temp, FieldOperand(temp, JSFunction::kContextOffset));
       // Walk the rest of the chain without clobbering rsi.
       context = temp;
     }
   }
   // Check that last extension is NULL.
   __ cmpq(ContextOperand(context, Context::EXTENSION_INDEX), Immediate(0));
   __ j(not_equal, slow);
-  __ movq(temp, ContextOperand(context, Context::FCONTEXT_INDEX));
-  return ContextOperand(temp, slot->index());
+
+  // This function is used only for loads, not stores, so it's safe to
+  // return an rsi-based operand (the write barrier cannot be allowed to
+  // destroy the rsi register).
+  return ContextOperand(context, slot->index());
 }
 
 
 void FullCodeGenerator::EmitDynamicLoadFromSlotFastCase(
     Slot* slot,
     TypeofState typeof_state,
     Label* slow,
     Label* done) {
   // Generate fast-case code for variables that might be shadowed by
   // eval-introduced variables.  Eval is used a lot without
@@ skipping 626 matching lines @@
     // Assignment to a global variable.  Use inline caching for the
     // assignment.  Right-hand-side value is passed in rax, variable name in
     // rcx, and the global object on the stack.
     __ Move(rcx, var->name());
     __ movq(rdx, GlobalObjectOperand());
     Handle<Code> ic(Builtins::builtin(is_strict()
         ? Builtins::StoreIC_Initialize_Strict
         : Builtins::StoreIC_Initialize));
     EmitCallIC(ic, RelocInfo::CODE_TARGET_CONTEXT);
 
-  } else if (var->mode() != Variable::CONST || op == Token::INIT_CONST) {
-    // Perform the assignment for non-const variables and for initialization
-    // of const variables.  Const assignments are simply skipped.
-    Label done;
+  } else if (op == Token::INIT_CONST) {
+    // Like var declarations, const declarations are hoisted to function
+    // scope.  However, unlike var initializers, const initializers are able
+    // to drill a hole to that function context, even from inside a 'with'
+    // context.  We thus bypass the normal static scope lookup.
+    Slot* slot = var->AsSlot();
+    Label skip;
+    switch (slot->type()) {
+      case Slot::PARAMETER:
+        // No const parameters.
+        UNREACHABLE();
+        break;
+      case Slot::LOCAL:
+        __ movq(rdx, Operand(rbp, SlotOffset(slot)));
+        __ CompareRoot(rdx, Heap::kTheHoleValueRootIndex);
+        __ j(not_equal, &skip);
+        __ movq(Operand(rbp, SlotOffset(slot)), rax);
+        break;
+      case Slot::CONTEXT: {
+        __ movq(rcx, ContextOperand(rsi, Context::FCONTEXT_INDEX));
+        __ movq(rdx, ContextOperand(rcx, slot->index()));
+        __ CompareRoot(rdx, Heap::kTheHoleValueRootIndex);
+        __ j(not_equal, &skip);
+        __ movq(ContextOperand(rcx, slot->index()), rax);
+        int offset = Context::SlotOffset(slot->index());
+        __ movq(rdx, rax);  // Preserve the stored value in eax.
+        __ RecordWrite(rcx, offset, rdx, rbx);
+        break;
+      }
+      case Slot::LOOKUP:
+        __ push(rax);
+        __ push(rsi);
+        __ Push(var->name());
+        __ CallRuntime(Runtime::kInitializeConstContextSlot, 3);
+        break;
+    }
+    __ bind(&skip);
+
+  } else if (var->mode() != Variable::CONST) {
+    // Perform the assignment for non-const variables.  Const assignments
+    // are simply skipped.
     Slot* slot = var->AsSlot();
     switch (slot->type()) {
       case Slot::PARAMETER:
       case Slot::LOCAL:
-        if (op == Token::INIT_CONST) {
-          // Detect const reinitialization by checking for the hole value.
-          __ movq(rdx, Operand(rbp, SlotOffset(slot)));
-          __ CompareRoot(rdx, Heap::kTheHoleValueRootIndex);
-          __ j(not_equal, &done);
-        }
         // Perform the assignment.
         __ movq(Operand(rbp, SlotOffset(slot)), rax);
         break;
 
       case Slot::CONTEXT: {
         MemOperand target = EmitSlotSearch(slot, rcx);
-        if (op == Token::INIT_CONST) {
-          // Detect const reinitialization by checking for the hole value.
-          __ movq(rdx, target);
-          __ CompareRoot(rdx, Heap::kTheHoleValueRootIndex);
-          __ j(not_equal, &done);
-        }
         // Perform the assignment and issue the write barrier.
         __ movq(target, rax);
         // The value of the assignment is in rax.  RecordWrite clobbers its
         // register arguments.
         __ movq(rdx, rax);
-        int offset = FixedArray::kHeaderSize + slot->index() * kPointerSize;
+        int offset = Context::SlotOffset(slot->index());
         __ RecordWrite(rcx, offset, rdx, rbx);
         break;
       }
 
       case Slot::LOOKUP:
-        // Call the runtime for the assignment.  The runtime will ignore
-        // const reinitialization.
+        // Call the runtime for the assignment.
         __ push(rax);  // Value.
         __ push(rsi);  // Context.
         __ Push(var->name());
-        if (op == Token::INIT_CONST) {
-          // The runtime will ignore const redeclaration.
-          __ CallRuntime(Runtime::kInitializeConstContextSlot, 3);
-        } else {
-          __ CallRuntime(Runtime::kStoreContextSlot, 3);
-        }
+        __ CallRuntime(Runtime::kStoreContextSlot, 3);
         break;
     }
-    __ bind(&done);
   }
 }
 
 
 void FullCodeGenerator::EmitNamedPropertyAssignment(Assignment* expr) {
   // Assignment to a property, using a named store IC.
   Property* prop = expr->target()->AsProperty();
   ASSERT(prop != NULL);
   ASSERT(prop->key()->AsLiteral() != NULL);
 
@@ skipping 1004 matching lines @@
   VisitForStackValue(args->at(1));
 
   StringCompareStub stub;
   __ CallStub(&stub);
   context()->Plug(rax);
 }
 
 
 void FullCodeGenerator::EmitMathSin(ZoneList<Expression*>* args) {
   // Load the argument on the stack and call the stub.
-  TranscendentalCacheStub stub(TranscendentalCache::SIN);
+  TranscendentalCacheStub stub(TranscendentalCache::SIN,
+                               TranscendentalCacheStub::TAGGED);
   ASSERT(args->length() == 1);
   VisitForStackValue(args->at(0));
   __ CallStub(&stub);
   context()->Plug(rax);
 }
 
 
 void FullCodeGenerator::EmitMathCos(ZoneList<Expression*>* args) {
   // Load the argument on the stack and call the stub.
-  TranscendentalCacheStub stub(TranscendentalCache::COS);
+  TranscendentalCacheStub stub(TranscendentalCache::COS,
+                               TranscendentalCacheStub::TAGGED);
   ASSERT(args->length() == 1);
   VisitForStackValue(args->at(0));
   __ CallStub(&stub);
   context()->Plug(rax);
 }
 
 
 void FullCodeGenerator::EmitMathLog(ZoneList<Expression*>* args) {
   // Load the argument on the stack and call the stub.
-  TranscendentalCacheStub stub(TranscendentalCache::LOG);
+  TranscendentalCacheStub stub(TranscendentalCache::LOG,
+                               TranscendentalCacheStub::TAGGED);
   ASSERT(args->length() == 1);
   VisitForStackValue(args->at(0));
   __ CallStub(&stub);
   context()->Plug(rax);
 }
 
 
 void FullCodeGenerator::EmitMathSqrt(ZoneList<Expression*>* args) {
   // Load the argument on the stack and call the runtime function.
   ASSERT(args->length() == 1);
@@ skipping 154 matching lines @@
   PrepareForBailoutBeforeSplit(TOS_REG, true, if_true, if_false);
   __ j(zero, if_true);
   __ jmp(if_false);
 
   context()->Plug(if_true, if_false);
 }
 
 
 void FullCodeGenerator::EmitGetCachedArrayIndex(ZoneList<Expression*>* args) {
   ASSERT(args->length() == 1);
+  VisitForAccumulatorValue(args->at(0));
 
-  VisitForAccumulatorValue(args->at(0));
+  if (FLAG_debug_code) {
+    __ AbortIfNotString(rax);
+  }
 
   __ movl(rax, FieldOperand(rax, String::kHashFieldOffset));
   ASSERT(String::kHashShift >= kSmiTagSize);
   __ IndexFromHash(rax, rax);
 
   context()->Plug(rax);
 }
 
 
 void FullCodeGenerator::EmitFastAsciiArrayJoin(ZoneList<Expression*>* args) {
@@ skipping 693 matching lines @@
       __ nop();  // Signals no inlined code.
       break;
     default:
       // Do nothing.
       break;
   }
 }
 
 
 void FullCodeGenerator::EmitCallIC(Handle<Code> ic, JumpPatchSite* patch_site) {
+  switch (ic->kind()) {
+    case Code::LOAD_IC:
+      __ IncrementCounter(&Counters::named_load_full, 1);
+      break;
+    case Code::KEYED_LOAD_IC:
+      __ IncrementCounter(&Counters::keyed_load_full, 1);
+      break;
+    case Code::STORE_IC:
+      __ IncrementCounter(&Counters::named_store_full, 1);
+      break;
+    case Code::KEYED_STORE_IC:
+      __ IncrementCounter(&Counters::keyed_store_full, 1);
+    default:
+      break;
+  }
+
   __ call(ic, RelocInfo::CODE_TARGET);
   if (patch_site != NULL && patch_site->is_bound()) {
     patch_site->EmitPatchInfo();
   } else {
     __ nop();  // Signals no inlined code.
   }
 }
 
 
 void FullCodeGenerator::StoreToFrameField(int frame_offset, Register value) {
@@ skipping 40 matching lines @@
   __ ret(0);
 }
 
 
 #undef __
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64