Only swap undefined for the global object if necessary in the prologue

BUG=

Review URL: https://codereview.chromium.org/1120093002

Cr-Commit-Position: refs/heads/master@{#28200}

diff --git a/src/arm/full-codegen-arm.cc b/src/arm/full-codegen-arm.cc
index 2154b6e..2522b09 100644 (file)
--- a/src/arm/full-codegen-arm.cc
+++ b/src/arm/full-codegen-arm.cc
@@ -126,7 +126,8 @@ void FullCodeGenerator::Generate() {
   // Sloppy mode functions and builtins need to replace the receiver with the
   // global proxy when called as functions (without an explicit receiver
   // object).
-  if (is_sloppy(info->language_mode()) && !info->is_native()) {
+  if (is_sloppy(info->language_mode()) && !info->is_native() &&
+      info->MayUseThis()) {
     Label ok;
     int receiver_offset = info->scope()->num_parameters() * kPointerSize;
     __ ldr(r2, MemOperand(sp, receiver_offset));

diff --git a/src/arm/lithium-codegen-arm.cc b/src/arm/lithium-codegen-arm.cc
index b480fd9..d11bfc7 100644 (file)
--- a/src/arm/lithium-codegen-arm.cc
+++ b/src/arm/lithium-codegen-arm.cc
@@ -120,7 +120,7 @@ bool LCodeGen::GeneratePrologue() {
     // Sloppy mode functions and builtins need to replace the receiver with the
     // global proxy when called as functions (without an explicit receiver
     // object).
-    if (graph()->this_has_uses() && is_sloppy(info_->language_mode()) &&
+    if (is_sloppy(info_->language_mode()) && info()->MayUseThis() &&
         !info_->is_native()) {
       Label ok;
       int receiver_offset = info_->scope()->num_parameters() * kPointerSize;

diff --git a/src/arm64/full-codegen-arm64.cc b/src/arm64/full-codegen-arm64.cc
index d1ee80e..af4a6d6 100644 (file)
--- a/src/arm64/full-codegen-arm64.cc
+++ b/src/arm64/full-codegen-arm64.cc
@@ -124,7 +124,8 @@ void FullCodeGenerator::Generate() {
   // Sloppy mode functions and builtins need to replace the receiver with the
   // global proxy when called as functions (without an explicit receiver
   // object).
-  if (is_sloppy(info->language_mode()) && !info->is_native()) {
+  if (is_sloppy(info->language_mode()) && !info->is_native() &&
+      info->MayUseThis()) {
     Label ok;
     int receiver_offset = info->scope()->num_parameters() * kXRegSize;
     __ Peek(x10, receiver_offset);

diff --git a/src/arm64/lithium-codegen-arm64.cc b/src/arm64/lithium-codegen-arm64.cc
index a249ca4..78e296b 100644 (file)
--- a/src/arm64/lithium-codegen-arm64.cc
+++ b/src/arm64/lithium-codegen-arm64.cc
@@ -668,7 +668,7 @@ bool LCodeGen::GeneratePrologue() {
     // Sloppy mode functions and builtins need to replace the receiver with the
     // global proxy when called as functions (without an explicit receiver
     // object).
-    if (graph()->this_has_uses() && is_sloppy(info()->language_mode()) &&
+    if (is_sloppy(info_->language_mode()) && info()->MayUseThis() &&
         !info_->is_native()) {
       Label ok;
       int receiver_offset = info_->scope()->num_parameters() * kXRegSize;

diff --git a/src/compiler.cc b/src/compiler.cc
index ada773c..2ad1ff4 100644 (file)
--- a/src/compiler.cc
+++ b/src/compiler.cc
@@ -214,6 +214,12 @@ bool CompilationInfo::is_simple_parameter_list() {
 }
 
 
+bool CompilationInfo::MayUseThis() const {
+  return scope()->uses_this() || scope()->inner_uses_this() ||
+         scope()->calls_sloppy_eval();
+}
+
+
 int CompilationInfo::TraceInlinedFunction(Handle<SharedFunctionInfo> shared,
                                           SourcePosition position,
                                           int parent_id) {

diff --git a/src/compiler.h b/src/compiler.h
index 8e0aab9..ff3a86a 100644 (file)
--- a/src/compiler.h
+++ b/src/compiler.h
@@ -148,6 +148,7 @@ class CompilationInfo {
   Handle<JSFunction> closure() const;
   FunctionLiteral* function() const;
   Scope* scope() const;
+  bool MayUseThis() const;
   Handle<Context> context() const;
   Handle<SharedFunctionInfo> shared_info() const;
   bool has_shared_info() const;

diff --git a/src/compiler/ast-graph-builder.cc b/src/compiler/ast-graph-builder.cc
index e62e34e..8842288 100644 (file)
--- a/src/compiler/ast-graph-builder.cc
+++ b/src/compiler/ast-graph-builder.cc
@@ -2642,10 +2642,7 @@ Node* AstGraphBuilder::BuildPatchReceiverToGlobalProxy(Node* receiver) {
   // There is no need to perform patching if the receiver is never used. Note
   // that scope predicates are purely syntactical, a call to eval might still
   // inspect the receiver value.
-  if (!info()->scope()->uses_this() && !info()->scope()->inner_uses_this() &&
-      !info()->scope()->calls_sloppy_eval()) {
-    return receiver;
-  }
+  if (!info()->MayUseThis()) return receiver;
 
   IfBuilder receiver_check(this);
   Node* undefined = jsgraph()->UndefinedConstant();

diff --git a/src/hydrogen.cc b/src/hydrogen.cc
index 788fda4..9bdc070 100644 (file)
--- a/src/hydrogen.cc
+++ b/src/hydrogen.cc
@@ -3496,7 +3496,6 @@ HGraph::HGraph(CompilationInfo* info)
       info_(info),
       zone_(info->zone()),
       is_recursive_(false),
-      this_has_uses_(false),
       use_optimistic_licm_(false),
       depends_on_empty_array_proto_elements_(false),
       type_change_checksum_(0),
@@ -5402,10 +5401,6 @@ HValue* HOptimizedGraphBuilder::BuildContextChainWalk(Variable* var) {
 
 
 void HOptimizedGraphBuilder::VisitVariableProxy(VariableProxy* expr) {
-  if (expr->is_this()) {
-    graph()->MarkThisHasUses();
-  }
-
   DCHECK(!HasStackOverflow());
   DCHECK(current_block() != NULL);
   DCHECK(current_block()->HasPredecessor());

diff --git a/src/hydrogen.h b/src/hydrogen.h
index f5fa62f..3eb34a2 100644 (file)
--- a/src/hydrogen.h
+++ b/src/hydrogen.h
@@ -410,9 +410,6 @@ class HGraph final : public ZoneObject {
   void MarkRecursive() { is_recursive_ = true; }
   bool is_recursive() const { return is_recursive_; }
 
-  void MarkThisHasUses() { this_has_uses_ = true; }
-  bool this_has_uses() const { return this_has_uses_; }
-
   void MarkDependsOnEmptyArrayProtoElements() {
     // Add map dependency if not already added.
     if (depends_on_empty_array_proto_elements_) return;
@@ -493,7 +490,6 @@ class HGraph final : public ZoneObject {
   Zone* zone_;
 
   bool is_recursive_;
-  bool this_has_uses_;
   bool use_optimistic_licm_;
   bool depends_on_empty_array_proto_elements_;
   int type_change_checksum_;

diff --git a/src/ia32/full-codegen-ia32.cc b/src/ia32/full-codegen-ia32.cc
index 6c38b70..7033301 100644 (file)
--- a/src/ia32/full-codegen-ia32.cc
+++ b/src/ia32/full-codegen-ia32.cc
@@ -114,7 +114,8 @@ void FullCodeGenerator::Generate() {
   // Sloppy mode functions and builtins need to replace the receiver with the
   // global proxy when called as functions (without an explicit receiver
   // object).
-  if (is_sloppy(info->language_mode()) && !info->is_native()) {
+  if (is_sloppy(info->language_mode()) && !info->is_native() &&
+      info->MayUseThis()) {
     Label ok;
     // +1 for return address.
     int receiver_offset = (info->scope()->num_parameters() + 1) * kPointerSize;

diff --git a/src/ia32/lithium-codegen-ia32.cc b/src/ia32/lithium-codegen-ia32.cc
index f28afa8..03fd248 100644 (file)
--- a/src/ia32/lithium-codegen-ia32.cc
+++ b/src/ia32/lithium-codegen-ia32.cc
@@ -141,7 +141,7 @@ bool LCodeGen::GeneratePrologue() {
     // Sloppy mode functions and builtins need to replace the receiver with the
     // global proxy when called as functions (without an explicit receiver
     // object).
-    if (graph()->this_has_uses() && is_sloppy(info_->language_mode()) &&
+    if (is_sloppy(info_->language_mode()) && info()->MayUseThis() &&
         !info_->is_native()) {
       Label ok;
       // +1 for return address.

diff --git a/src/mips/full-codegen-mips.cc b/src/mips/full-codegen-mips.cc
index 24d448d..0756b09 100644 (file)
--- a/src/mips/full-codegen-mips.cc
+++ b/src/mips/full-codegen-mips.cc
@@ -134,7 +134,8 @@ void FullCodeGenerator::Generate() {
   // Sloppy mode functions and builtins need to replace the receiver with the
   // global proxy when called as functions (without an explicit receiver
   // object).
-  if (is_sloppy(info->language_mode()) && !info->is_native()) {
+  if (is_sloppy(info->language_mode()) && !info->is_native() &&
+      info->MayUseThis()) {
     Label ok;
     int receiver_offset = info->scope()->num_parameters() * kPointerSize;
     __ lw(at, MemOperand(sp, receiver_offset));

diff --git a/src/mips/lithium-codegen-mips.cc b/src/mips/lithium-codegen-mips.cc
index 2abde16..e5adc80 100644 (file)
--- a/src/mips/lithium-codegen-mips.cc
+++ b/src/mips/lithium-codegen-mips.cc
@@ -143,7 +143,7 @@ bool LCodeGen::GeneratePrologue() {
     // Sloppy mode functions and builtins need to replace the receiver with the
     // global proxy when called as functions (without an explicit receiver
     // object).
-    if (graph()->this_has_uses() && is_sloppy(info_->language_mode()) &&
+    if (is_sloppy(info_->language_mode()) && info()->MayUseThis() &&
         !info_->is_native()) {
       Label ok;
       int receiver_offset = info_->scope()->num_parameters() * kPointerSize;

diff --git a/src/mips64/full-codegen-mips64.cc b/src/mips64/full-codegen-mips64.cc
index b3ed1bb..0e3f072 100644 (file)
--- a/src/mips64/full-codegen-mips64.cc
+++ b/src/mips64/full-codegen-mips64.cc
@@ -134,7 +134,8 @@ void FullCodeGenerator::Generate() {
   // Sloppy mode functions and builtins need to replace the receiver with the
   // global proxy when called as functions (without an explicit receiver
   // object).
-  if (is_sloppy(info->language_mode()) && !info->is_native()) {
+  if (is_sloppy(info->language_mode()) && !info->is_native() &&
+      info->MayUseThis()) {
     Label ok;
     int receiver_offset = info->scope()->num_parameters() * kPointerSize;
     __ ld(at, MemOperand(sp, receiver_offset));

diff --git a/src/mips64/lithium-codegen-mips64.cc b/src/mips64/lithium-codegen-mips64.cc
index 58ea58c..ed0e5f5 100644 (file)
--- a/src/mips64/lithium-codegen-mips64.cc
+++ b/src/mips64/lithium-codegen-mips64.cc
@@ -118,7 +118,7 @@ bool LCodeGen::GeneratePrologue() {
     // Sloppy mode functions and builtins need to replace the receiver with the
     // global proxy when called as functions (without an explicit receiver
     // object).
-    if (graph()->this_has_uses() && is_sloppy(info_->language_mode()) &&
+    if (is_sloppy(info_->language_mode()) && info()->MayUseThis() &&
         !info_->is_native()) {
       Label ok;
       int receiver_offset = info_->scope()->num_parameters() * kPointerSize;

diff --git a/src/x64/full-codegen-x64.cc b/src/x64/full-codegen-x64.cc
index 94da774..7f0f66d 100644 (file)
--- a/src/x64/full-codegen-x64.cc
+++ b/src/x64/full-codegen-x64.cc
@@ -114,7 +114,8 @@ void FullCodeGenerator::Generate() {
   // Sloppy mode functions and builtins need to replace the receiver with the
   // global proxy when called as functions (without an explicit receiver
   // object).
-  if (is_sloppy(info->language_mode()) && !info->is_native()) {
+  if (is_sloppy(info->language_mode()) && !info->is_native() &&
+      info->MayUseThis()) {
     Label ok;
     // +1 for return address.
     StackArgumentsAccessor args(rsp, info->scope()->num_parameters());

diff --git a/src/x64/lithium-codegen-x64.cc b/src/x64/lithium-codegen-x64.cc
index e70bebd..51b85fc 100644 (file)
--- a/src/x64/lithium-codegen-x64.cc
+++ b/src/x64/lithium-codegen-x64.cc
@@ -129,7 +129,7 @@ bool LCodeGen::GeneratePrologue() {
 
     // Sloppy mode functions need to replace the receiver with the global proxy
     // when called as functions (without an explicit receiver object).
-    if (graph()->this_has_uses() && is_sloppy(info_->language_mode()) &&
+    if (is_sloppy(info_->language_mode()) && info()->MayUseThis() &&
         !info_->is_native()) {
       Label ok;
       StackArgumentsAccessor args(rsp, scope()->num_parameters());

diff --git a/src/x87/full-codegen-x87.cc b/src/x87/full-codegen-x87.cc
index 3a6edec..3dbb6d4 100644 (file)
--- a/src/x87/full-codegen-x87.cc
+++ b/src/x87/full-codegen-x87.cc
@@ -114,7 +114,8 @@ void FullCodeGenerator::Generate() {
   // Sloppy mode functions and builtins need to replace the receiver with the
   // global proxy when called as functions (without an explicit receiver
   // object).
-  if (is_sloppy(info->language_mode()) && !info->is_native()) {
+  if (is_sloppy(info->language_mode()) && !info->is_native() &&
+      info->MayUseThis()) {
     Label ok;
     // +1 for return address.
     int receiver_offset = (info->scope()->num_parameters() + 1) * kPointerSize;

diff --git a/src/x87/lithium-codegen-x87.cc b/src/x87/lithium-codegen-x87.cc
index af118d5..ba650ab 100644 (file)
--- a/src/x87/lithium-codegen-x87.cc
+++ b/src/x87/lithium-codegen-x87.cc
@@ -110,7 +110,7 @@ bool LCodeGen::GeneratePrologue() {
     // Sloppy mode functions and builtins need to replace the receiver with the
     // global proxy when called as functions (without an explicit receiver
     // object).
-    if (graph()->this_has_uses() && is_sloppy(info_->language_mode()) &&
+    if (is_sloppy(info_->language_mode()) && info()->MayUseThis() &&
         !info_->is_native()) {
       Label ok;
       // +1 for return address.