Revert of [debugger] remove debugger statement support from FCG/CS. (patchset...

Revert of [debugger] remove debugger statement support from FCG/CS. (patchset #5 id:80001 of https://codereview.chromium.org/2650193002/ )

Reason for revert:
Fails on chromium leak bot:
https://uberchromegw.corp.google.com/i/chromium.webkit/builders/WebKit%20Linux%20Trusty%20Leak/builds/2007

Original issue's description:
> [debugger] remove debugger statement support from FCG/CS.
>
>
> R=mstarzinger@chromium.org
>
> Review-Url: https://codereview.chromium.org/2650193002
> Cr-Commit-Position: refs/heads/master@{#42892}
> Committed: https://chromium.googlesource.com/v8/v8/+/eef855a1dc956e9db03ec09abca1d732d379861b

TBR=mstarzinger@chromium.org,yangguo@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.

Review-Url: https://codereview.chromium.org/2672823007
Cr-Commit-Position: refs/heads/master@{#42942}

src/arm/macro-assembler-arm.cc

@@ -1919,6 +1919,16 @@ void MacroAssembler::IsObjectNameType(Register object,
   b(hi, fail);
 }
 
+
+void MacroAssembler::DebugBreak() {
+  mov(r0, Operand::Zero());
+  mov(r1,
+      Operand(ExternalReference(Runtime::kHandleDebuggerStatement, isolate())));
+  CEntryStub ces(isolate(), 1);
+  DCHECK(AllowThisStubCall(&ces));
+  Call(ces.GetCode(), RelocInfo::DEBUGGER_STATEMENT);
+}
+
 void MacroAssembler::MaybeDropFrames() {
   // Check whether we need to drop frames to restart a function on the stack.
   ExternalReference restart_fp =

src/arm/macro-assembler-arm.h

@@ -714,9 +714,13 @@ class MacroAssembler: public Assembler {
                         Register scratch,
                         Label* fail);
 
-  // Frame restart support
+  // ---------------------------------------------------------------------------
+  // Debugger Support
+
+  void DebugBreak();
   void MaybeDropFrames();
 
+  // ---------------------------------------------------------------------------
   // Exception handling
 
   // Push a new stack handler and link into stack handler chain.

src/arm64/macro-assembler-arm64.cc

@@ -2888,6 +2888,15 @@ void MacroAssembler::LoadContext(Register dst, int context_chain_length) {
   }
 }
 
+
+void MacroAssembler::DebugBreak() {
+  Mov(x0, 0);
+  Mov(x1, ExternalReference(Runtime::kHandleDebuggerStatement, isolate()));
+  CEntryStub ces(isolate(), 1);
+  DCHECK(AllowThisStubCall(&ces));
+  Call(ces.GetCode(), RelocInfo::DEBUGGER_STATEMENT);
+}
+
 void MacroAssembler::MaybeDropFrames() {
   // Check whether we need to drop frames to restart a function on the stack.
   ExternalReference restart_fp =

src/arm64/macro-assembler-arm64.h

@@ -1300,9 +1300,13 @@ class MacroAssembler : public Assembler {
     MacroAssembler* masm_;
   };
 
-  // Frame restart support
+  // ---------------------------------------------------------------------------
+  // Debugger Support
+
+  void DebugBreak();
   void MaybeDropFrames();
 
+  // ---------------------------------------------------------------------------
   // Exception handling
 
   // Push a new stack handler and link into stack handler chain.

src/assembler.cc

@@ -725,6 +725,8 @@ const char* RelocInfo::RelocModeName(RelocInfo::Mode rmode) {
       return "no reloc 64";
     case EMBEDDED_OBJECT:
       return "embedded object";
+    case DEBUGGER_STATEMENT:
+      return "debugger statement";
     case CODE_TARGET:
       return "code target";
     case CODE_TARGET_WITH_ID:
@@ -832,6 +834,7 @@ void RelocInfo::Verify(Isolate* isolate) {
     case CELL:
       Object::VerifyPointer(target_cell());
       break;
+    case DEBUGGER_STATEMENT:
     case CODE_TARGET_WITH_ID:
     case CODE_TARGET: {
       // convert inline target address to code object

src/assembler.h

@@ -317,6 +317,7 @@ class RelocInfo {
     // Please note the order is important (see IsCodeTarget, IsGCRelocMode).
     CODE_TARGET,  // Code target which is not any of the above.
     CODE_TARGET_WITH_ID,
+    DEBUGGER_STATEMENT,  // Code target for the debugger statement.
     EMBEDDED_OBJECT,
     // To relocate pointers into the wasm memory embedded in wasm code
     WASM_MEMORY_REFERENCE,
@@ -365,7 +366,7 @@ class RelocInfo {
 
     FIRST_REAL_RELOC_MODE = CODE_TARGET,
     LAST_REAL_RELOC_MODE = VENEER_POOL,
-    LAST_CODE_ENUM = CODE_TARGET_WITH_ID,
+    LAST_CODE_ENUM = DEBUGGER_STATEMENT,
     LAST_GCED_ENUM = WASM_FUNCTION_TABLE_SIZE_REFERENCE,
     FIRST_SHAREABLE_RELOC_MODE = CELL,
   };
@@ -441,6 +442,9 @@ class RelocInfo {
   static inline bool IsDebugBreakSlotAtTailCall(Mode mode) {
     return mode == DEBUG_BREAK_SLOT_AT_TAIL_CALL;
   }
+  static inline bool IsDebuggerStatement(Mode mode) {
+    return mode == DEBUGGER_STATEMENT;
+  }
   static inline bool IsNone(Mode mode) {
     return mode == NONE32 || mode == NONE64;
   }

src/ast/ast-numbering.cc

@@ -119,7 +119,8 @@ void AstNumberingVisitor::VisitBreakStatement(BreakStatement* node) {
 
 void AstNumberingVisitor::VisitDebuggerStatement(DebuggerStatement* node) {
   IncrementNodeCount();
-  DisableFullCodegenAndCrankshaft(kDebuggerStatement);
+  DisableOptimization(kDebuggerStatement);
+  node->set_base_id(ReserveIdRange(DebuggerStatement::num_ids()));
 }
 
 

src/ast/ast.h

@@ -1146,10 +1146,26 @@ class TryFinallyStatement final : public TryStatement {
 
 
 class DebuggerStatement final : public Statement {
+ public:
+  void set_base_id(int id) { base_id_ = id; }
+  static int num_ids() { return parent_num_ids() + 1; }
+  BailoutId DebugBreakId() const { return BailoutId(local_id(0)); }
+
  private:
   friend class AstNodeFactory;
 
-  explicit DebuggerStatement(int pos) : Statement(pos, kDebuggerStatement) {}
+  explicit DebuggerStatement(int pos)
+      : Statement(pos, kDebuggerStatement),
+        base_id_(BailoutId::None().ToInt()) {}
+
+  static int parent_num_ids() { return 0; }
+  int base_id() const {
+    DCHECK(!BailoutId(base_id_).IsNone());
+    return base_id_;
+  }
+  int local_id(int n) const { return base_id() + parent_num_ids() + n; }
+
+  int base_id_;
 };
 
 

src/compiler/ast-graph-builder.cc

@@ -1286,8 +1286,9 @@ void AstGraphBuilder::VisitTryFinallyStatement(TryFinallyStatement* stmt) {
 
 
 void AstGraphBuilder::VisitDebuggerStatement(DebuggerStatement* stmt) {
-  // Debugger statement is supported only by going through Ignition first.
-  UNREACHABLE();
+  Node* node = NewNode(javascript()->Debugger());
+  PrepareFrameState(node, stmt->DebugBreakId());
+  environment()->MarkAllLocalsLive();
 }
 
 

src/debug/debug.cc

@@ -186,6 +186,7 @@ int CodeBreakIterator::GetModeMask() {
   mask |= RelocInfo::ModeMask(RelocInfo::DEBUG_BREAK_SLOT_AT_CALL);
   mask |= RelocInfo::ModeMask(RelocInfo::DEBUG_BREAK_SLOT_AT_TAIL_CALL);
   mask |= RelocInfo::ModeMask(RelocInfo::DEBUG_BREAK_SLOT_AT_POSITION);
+  mask |= RelocInfo::ModeMask(RelocInfo::DEBUGGER_STATEMENT);
   return mask;
 }
 
@@ -210,7 +211,8 @@ void CodeBreakIterator::Next() {
     source_position_iterator_.Advance();
   }
 
-  DCHECK(RelocInfo::IsDebugBreakSlot(rmode()));
+  DCHECK(RelocInfo::IsDebugBreakSlot(rmode()) ||
+         RelocInfo::IsDebuggerStatement(rmode()));
   break_index_++;
 }
 
@@ -223,6 +225,8 @@ DebugBreakType CodeBreakIterator::GetDebugBreakType() {
     return isolate()->is_tail_call_elimination_enabled()
                ? DEBUG_BREAK_SLOT_AT_TAIL_CALL
                : DEBUG_BREAK_SLOT_AT_CALL;
+  } else if (RelocInfo::IsDebuggerStatement(rmode())) {
+    return DEBUGGER_STATEMENT;
   } else if (RelocInfo::IsDebugBreakSlot(rmode())) {
     return DEBUG_BREAK_SLOT;
   } else {
@@ -238,6 +242,7 @@ void CodeBreakIterator::SkipToPosition(int position,
 
 void CodeBreakIterator::SetDebugBreak() {
   DebugBreakType debug_break_type = GetDebugBreakType();
+  if (debug_break_type == DEBUGGER_STATEMENT) return;
   DCHECK(debug_break_type >= DEBUG_BREAK_SLOT);
   Builtins* builtins = isolate()->builtins();
   Handle<Code> target = debug_break_type == DEBUG_BREAK_SLOT_AT_RETURN
@@ -247,12 +252,16 @@ void CodeBreakIterator::SetDebugBreak() {
 }
 
 void CodeBreakIterator::ClearDebugBreak() {
-  DCHECK(GetDebugBreakType() >= DEBUG_BREAK_SLOT);
+  DebugBreakType debug_break_type = GetDebugBreakType();
+  if (debug_break_type == DEBUGGER_STATEMENT) return;
+  DCHECK(debug_break_type >= DEBUG_BREAK_SLOT);
   DebugCodegen::ClearDebugBreakSlot(isolate(), rinfo()->pc());
 }
 
 bool CodeBreakIterator::IsDebugBreak() {
-  DCHECK(GetDebugBreakType() >= DEBUG_BREAK_SLOT);
+  DebugBreakType debug_break_type = GetDebugBreakType();
+  if (debug_break_type == DEBUGGER_STATEMENT) return false;
+  DCHECK(debug_break_type >= DEBUG_BREAK_SLOT);
   return DebugCodegen::DebugBreakSlotIsPatched(rinfo()->pc());
 }
 

src/full-codegen/full-codegen.cc

@@ -1228,8 +1228,13 @@ void FullCodeGenerator::VisitTryFinallyStatement(TryFinallyStatement* stmt) {
 
 
 void FullCodeGenerator::VisitDebuggerStatement(DebuggerStatement* stmt) {
-  // Debugger statement is not supported.
-  UNREACHABLE();
+  Comment cmnt(masm_, "[ DebuggerStatement");
+  SetStatementPosition(stmt);
+
+  __ DebugBreak();
+  __ MaybeDropFrames();
+
+  PrepareForBailoutForId(stmt->DebugBreakId(), BailoutState::NO_REGISTERS);
 }
 
 

src/ia32/macro-assembler-ia32.cc

@@ -673,6 +673,14 @@ void MacroAssembler::RecordWriteCodeEntryField(Register js_function,
   bind(&done);
 }
 
+void MacroAssembler::DebugBreak() {
+  Move(eax, Immediate(0));
+  mov(ebx, Immediate(ExternalReference(Runtime::kHandleDebuggerStatement,
+                                       isolate())));
+  CEntryStub ces(isolate(), 1);
+  call(ces.GetCode(), RelocInfo::DEBUGGER_STATEMENT);
+}
+
 void MacroAssembler::MaybeDropFrames() {
   // Check whether we need to drop frames to restart a function on the stack.
   ExternalReference restart_fp =

src/ia32/macro-assembler-ia32.h

@@ -228,7 +228,10 @@ class MacroAssembler: public Assembler {
   void RecordWriteForMap(Register object, Handle<Map> map, Register scratch1,
                          Register scratch2, SaveFPRegsMode save_fp);
 
-  // Frame restart support
+  // ---------------------------------------------------------------------------
+  // Debugger Support
+
+  void DebugBreak();
   void MaybeDropFrames();
 
   // Generates function and stub prologue code.

src/mips/macro-assembler-mips.cc

@@ -3885,6 +3885,16 @@ void MacroAssembler::Push(Handle<Object> handle) {
   push(at);
 }
 
+
+void MacroAssembler::DebugBreak() {
+  PrepareCEntryArgs(0);
+  PrepareCEntryFunction(
+      ExternalReference(Runtime::kHandleDebuggerStatement, isolate()));
+  CEntryStub ces(isolate(), 1);
+  DCHECK(AllowThisStubCall(&ces));
+  Call(ces.GetCode(), RelocInfo::DEBUGGER_STATEMENT);
+}
+
 void MacroAssembler::MaybeDropFrames() {
   // Check whether we need to drop frames to restart a function on the stack.
   ExternalReference restart_fp =

src/mips/macro-assembler-mips.h

@@ -1080,9 +1080,13 @@ class MacroAssembler: public Assembler {
                         Register scratch,
                         Label* fail);
 
-  // Frame restart support.
+  // -------------------------------------------------------------------------
+  // Debugger Support.
+
+  void DebugBreak();
   void MaybeDropFrames();
 
+  // -------------------------------------------------------------------------
   // Exception handling.
 
   // Push a new stack handler and link into stack handler chain.

src/mips64/macro-assembler-mips64.cc

@@ -4040,6 +4040,16 @@ void MacroAssembler::PopRegisterAsTwoSmis(Register dst, Register scratch) {
   or_(dst, dst, scratch);
 }
 
+
+void MacroAssembler::DebugBreak() {
+  PrepareCEntryArgs(0);
+  PrepareCEntryFunction(
+      ExternalReference(Runtime::kHandleDebuggerStatement, isolate()));
+  CEntryStub ces(isolate(), 1);
+  DCHECK(AllowThisStubCall(&ces));
+  Call(ces.GetCode(), RelocInfo::DEBUGGER_STATEMENT);
+}
+
 void MacroAssembler::MaybeDropFrames() {
   // Check whether we need to drop frames to restart a function on the stack.
   ExternalReference restart_fp =

src/mips64/macro-assembler-mips64.h

@@ -1134,9 +1134,13 @@ class MacroAssembler: public Assembler {
                         Register scratch,
                         Label* fail);
 
-  // Frame restart support.
+  // -------------------------------------------------------------------------
+  // Debugger Support.
+
+  void DebugBreak();
   void MaybeDropFrames();
 
+  // -------------------------------------------------------------------------
   // Exception handling.
 
   // Push a new stack handler and link into stack handler chain.

src/x64/macro-assembler-x64.cc

@@ -4088,6 +4088,11 @@ void MacroAssembler::DecrementCounter(StatsCounter* counter, int value) {
   }
 }
 
+void MacroAssembler::DebugBreak() {
+  Call(isolate()->builtins()->HandleDebuggerStatement(),
+       RelocInfo::DEBUGGER_STATEMENT);
+}
+
 void MacroAssembler::MaybeDropFrames() {
   // Check whether we need to drop frames to restart a function on the stack.
   ExternalReference restart_fp =

src/x64/macro-assembler-x64.h

@@ -323,7 +323,10 @@ class MacroAssembler: public Assembler {
       PointersToHereCheck pointers_to_here_check_for_value =
           kPointersToHereMaybeInteresting);
 
-  // Frame restart support.
+  // ---------------------------------------------------------------------------
+  // Debugger Support
+
+  void DebugBreak();
   void MaybeDropFrames();
 
   // Generates function and stub prologue code.

test/cctest/test-profile-generator.cc

@@ -697,8 +697,6 @@ TEST(LineNumber) {
 }
 
 TEST(BailoutReason) {
-  i::FLAG_allow_natives_syntax = true;
-  i::FLAG_always_opt = false;
   v8::HandleScope scope(CcTest::isolate());
   v8::Local<v8::Context> env = CcTest::NewContext(PROFILER_EXTENSION);
   v8::Context::Scope context_scope(env);
@@ -706,21 +704,14 @@ TEST(BailoutReason) {
   i::ProfilerExtension::set_profiler(iprofiler.get());
 
   CHECK_EQ(0, iprofiler->GetProfilesCount());
-  v8::Local<v8::Function> function = CompileRun(
-                                         "function Debugger() {\n"
-                                         "  startProfiling();\n"
-                                         "}"
-                                         "Debugger")
-                                         .As<v8::Function>();
-  i::Handle<i::JSFunction> i_function =
-      i::Handle<i::JSFunction>::cast(v8::Utils::OpenHandle(*function));
-  // Set a high opt count to trigger bail out.
-  i_function->shared()->set_opt_count(10000);
-
-  CompileRun(
-      "%OptimizeFunctionOnNextCall(Debugger);"
-      "Debugger();"
-      "stopProfiling()");
+  v8::Local<v8::Script> script =
+      v8_compile(v8_str("function Debugger() {\n"
+                        "  debugger;\n"
+                        "  startProfiling();\n"
+                        "}\n"
+                        "Debugger();\n"
+                        "stopProfiling();"));
+  script->Run(v8::Isolate::GetCurrent()->GetCurrentContext()).ToLocalChecked();
   CHECK_EQ(1, iprofiler->GetProfilesCount());
   const v8::CpuProfile* profile = i::ProfilerExtension::last_profile;
   CHECK(profile);
@@ -730,11 +721,11 @@ TEST(BailoutReason) {
   // The tree should look like this:
   //  (root)
   //   ""
-  //     kFunctionBeingDebugged
+  //     kDebuggerStatement
   current = PickChild(current, "");
   CHECK(const_cast<v8::CpuProfileNode*>(current));
 
   current = PickChild(current, "Debugger");
   CHECK(const_cast<v8::CpuProfileNode*>(current));
-  CHECK(!strcmp("Deoptimized too many times", current->GetBailoutReason()));
+  CHECK(!strcmp("DebuggerStatement", current->GetBailoutReason()));
 }

test/debugger/debug/debug-evaluate-closure.js

@@ -25,7 +25,6 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-// Flags: --no-always-opt
 
 Debug = debug.Debug;
 var listened = false;

test/debugger/debug/debug-set-variable-value.js

@@ -25,7 +25,6 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-// Flags: --no-always-opt
 
 var Debug = debug.Debug;
 

test/debugger/debug/es6/debug-evaluate-blockscopes.js

@@ -29,8 +29,6 @@
 // Test debug evaluation for functions without local context, but with
 // nested catch contexts.
 
-// Flags: --no-always-opt
-
 "use strict";
 
 var x;

test/debugger/debug/regress/regress-crbug-323936.js

@@ -2,7 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// Flags: --no-always-opt
 
 Debug = debug.Debug;