Fix lazy deoptimization at HInvokeFunction and enable target-recording call-function stub.

src/arm/lithium-codegen-arm.cc

Index: src/arm/lithium-codegen-arm.cc
===================================================================
--- src/arm/lithium-codegen-arm.cc	(revision 9915)
+++ src/arm/lithium-codegen-arm.cc	(working copy)
@@ -40,37 +40,22 @@
  public:
   SafepointGenerator(LCodeGen* codegen,
                      LPointerMap* pointers,
-                     int deoptimization_index)
+                     Safepoint::DeoptMode mode)
       : codegen_(codegen),
         pointers_(pointers),
-        deoptimization_index_(deoptimization_index) { }
+        deopt_mode_(mode) { }
   virtual ~SafepointGenerator() { }
 
-  virtual void BeforeCall(int call_size) const {
-    ASSERT(call_size >= 0);
-    // Ensure that we have enough space after the previous safepoint position
-    // for the generated code there.
-    int call_end = codegen_->masm()->pc_offset() + call_size;
-    int prev_jump_end =
-        codegen_->LastSafepointEnd() + Deoptimizer::patch_size();
-    if (call_end < prev_jump_end) {
-      int padding_size = prev_jump_end - call_end;
-      ASSERT_EQ(0, padding_size % Assembler::kInstrSize);
-      while (padding_size > 0) {
-        codegen_->masm()->nop();
-        padding_size -= Assembler::kInstrSize;
-      }
-    }
-  }
+  virtual void BeforeCall(int call_size) const { }
 
   virtual void AfterCall() const {
-    codegen_->RecordSafepoint(pointers_, deoptimization_index_);
+    codegen_->RecordSafepoint(pointers_, deopt_mode_);
   }
 
  private:
   LCodeGen* codegen_;
   LPointerMap* pointers_;
-  int deoptimization_index_;
+  Safepoint::DeoptMode deopt_mode_;
 };
 
 
@@ -103,7 +88,6 @@
   code->set_stack_slots(GetStackSlotCount());
   code->set_safepoint_table_offset(safepoints_.GetCodeOffset());
   PopulateDeoptimizationData(code);
-  Deoptimizer::EnsureRelocSpaceForLazyDeoptimization(code);
 }
 
 
@@ -200,7 +184,7 @@
     } else {
       __ CallRuntime(Runtime::kNewFunctionContext, 1);
     }
-    RecordSafepoint(Safepoint::kNoDeoptimizationIndex);
+    RecordSafepoint(Safepoint::kNoLazyDeopt);
     // Context is returned in both r0 and cp.  It replaces the context
     // passed to us.  It's saved in the stack and kept live in cp.
     __ str(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
@@ -253,15 +237,6 @@
 }
 
 
-LInstruction* LCodeGen::GetNextInstruction() {
-  if (current_instruction_ < instructions_->length() - 1) {
-    return instructions_->at(current_instruction_ + 1);
-  } else {
-    return NULL;
-  }
-}
-
-
 bool LCodeGen::GenerateDeferredCode() {
   ASSERT(is_generating());
   if (deferred_.length() > 0) {
@@ -274,13 +249,6 @@
       code->Generate();
       __ jmp(code->exit());
     }
-
-    // Pad code to ensure that the last piece of deferred code have
-    // room for lazy bailout.
-    while ((masm()->pc_offset() - LastSafepointEnd())
-           < Deoptimizer::patch_size()) {
-      __ nop();

[Vyacheslav Egorov (Chromium), 2011/11/15 12:03:56]

Maybe add an assertion to check that we always have enough space for patching
(or at least a comment about why it is so).

Especially interesting is the case at the end of the function: @call
@lazy-bailout @return

[fschneider, 2011/11/15 13:35:24]

Done.

-    }
   }
 
   // Force constant pool emission at the end of the deferred code to make
@@ -566,7 +534,7 @@
   LPointerMap* pointers = instr->pointer_map();
   RecordPosition(pointers->position());
   __ Call(code, mode);
-  RegisterLazyDeoptimization(instr, safepoint_mode);
+  RecordSafepointWithLazyDeopt(instr, safepoint_mode);
 
   // Signal that we don't inline smi code before these stubs in the
   // optimizing code generator.
@@ -586,7 +554,7 @@
   RecordPosition(pointers->position());
 
   __ CallRuntime(function, num_arguments);
-  RegisterLazyDeoptimization(instr, RECORD_SIMPLE_SAFEPOINT);
+  RecordSafepointWithLazyDeopt(instr, RECORD_SIMPLE_SAFEPOINT);
 }
 
 
@@ -595,37 +563,12 @@
                                        LInstruction* instr) {
   __ CallRuntimeSaveDoubles(id);
   RecordSafepointWithRegisters(
-      instr->pointer_map(), argc, Safepoint::kNoDeoptimizationIndex);
+      instr->pointer_map(), argc, Safepoint::kNoLazyDeopt);
 }
 
 
-void LCodeGen::RegisterLazyDeoptimization(LInstruction* instr,
-                                          SafepointMode safepoint_mode) {
-  // Create the environment to bailout to. If the call has side effects
-  // execution has to continue after the call otherwise execution can continue
-  // from a previous bailout point repeating the call.
-  LEnvironment* deoptimization_environment;
-  if (instr->HasDeoptimizationEnvironment()) {
-    deoptimization_environment = instr->deoptimization_environment();
-  } else {
-    deoptimization_environment = instr->environment();
-  }
-
-  RegisterEnvironmentForDeoptimization(deoptimization_environment);
-  if (safepoint_mode == RECORD_SIMPLE_SAFEPOINT) {
-    RecordSafepoint(instr->pointer_map(),
-                    deoptimization_environment->deoptimization_index());
-  } else {
-    ASSERT(safepoint_mode == RECORD_SAFEPOINT_WITH_REGISTERS_AND_NO_ARGUMENTS);
-    RecordSafepointWithRegisters(
-        instr->pointer_map(),
-        0,
-        deoptimization_environment->deoptimization_index());
-  }
-}
-
-
-void LCodeGen::RegisterEnvironmentForDeoptimization(LEnvironment* environment) {
+void LCodeGen::RegisterEnvironmentForDeoptimization(LEnvironment* environment,
+                                                    Safepoint::DeoptMode mode) {
   if (!environment->HasBeenRegistered()) {
     // Physical stack frame layout:
     // -x ............. -4  0 ..................................... y
@@ -647,14 +590,17 @@
     Translation translation(&translations_, frame_count);
     WriteTranslation(environment, &translation);
     int deoptimization_index = deoptimizations_.length();
-    environment->Register(deoptimization_index, translation.index());
+    int pc_offset = masm()->pc_offset();
+    environment->Register(deoptimization_index,
+                          translation.index(),
+                          (mode == Safepoint::kLazyDeopt) ? pc_offset : -1);
     deoptimizations_.Add(environment);
   }
 }
 
 
 void LCodeGen::DeoptimizeIf(Condition cc, LEnvironment* environment) {
-  RegisterEnvironmentForDeoptimization(environment);
+  RegisterEnvironmentForDeoptimization(environment, Safepoint::kNoLazyDeopt);
   ASSERT(environment->HasBeenRegistered());
   int id = environment->deoptimization_index();
   Address entry = Deoptimizer::GetDeoptimizationEntry(id, Deoptimizer::EAGER);
@@ -716,6 +662,7 @@
     data->SetTranslationIndex(i, Smi::FromInt(env->translation_index()));
     data->SetArgumentsStackHeight(i,
                                   Smi::FromInt(env->arguments_stack_height()));
+    data->SetPc(i, Smi::FromInt(env->pc_offset()));
   }
   code->set_deoptimization_data(*data);
 }
@@ -747,16 +694,28 @@
 }
 
 
+void LCodeGen::RecordSafepointWithLazyDeopt(
+    LInstruction* instr, SafepointMode safepoint_mode) {
+  if (safepoint_mode == RECORD_SIMPLE_SAFEPOINT) {
+    RecordSafepoint(instr->pointer_map(), Safepoint::kLazyDeopt);
+  } else {
+    ASSERT(safepoint_mode == RECORD_SAFEPOINT_WITH_REGISTERS_AND_NO_ARGUMENTS);
+    RecordSafepointWithRegisters(
+        instr->pointer_map(), 0, Safepoint::kLazyDeopt);
+  }
+}
+
+
 void LCodeGen::RecordSafepoint(
     LPointerMap* pointers,
     Safepoint::Kind kind,
     int arguments,
-    int deoptimization_index) {
+    Safepoint::DeoptMode deopt_mode) {
   ASSERT(expected_safepoint_kind_ == kind);
 
   const ZoneList<LOperand*>* operands = pointers->GetNormalizedOperands();
   Safepoint safepoint = safepoints_.DefineSafepoint(masm(),
-      kind, arguments, deoptimization_index);
+      kind, arguments, deopt_mode);
   for (int i = 0; i < operands->length(); i++) {
     LOperand* pointer = operands->at(i);
     if (pointer->IsStackSlot()) {
@@ -773,31 +732,31 @@
 
 
 void LCodeGen::RecordSafepoint(LPointerMap* pointers,
-                               int deoptimization_index) {
-  RecordSafepoint(pointers, Safepoint::kSimple, 0, deoptimization_index);
+                               Safepoint::DeoptMode deopt_mode) {
+  RecordSafepoint(pointers, Safepoint::kSimple, 0, deopt_mode);
 }
 
 
-void LCodeGen::RecordSafepoint(int deoptimization_index) {
+void LCodeGen::RecordSafepoint(Safepoint::DeoptMode deopt_mode) {
   LPointerMap empty_pointers(RelocInfo::kNoPosition);
-  RecordSafepoint(&empty_pointers, deoptimization_index);
+  RecordSafepoint(&empty_pointers, deopt_mode);
 }
 
 
 void LCodeGen::RecordSafepointWithRegisters(LPointerMap* pointers,
                                             int arguments,
-                                            int deoptimization_index) {
-  RecordSafepoint(pointers, Safepoint::kWithRegisters, arguments,
-      deoptimization_index);
+                                            Safepoint::DeoptMode deopt_mode) {
+  RecordSafepoint(
+      pointers, Safepoint::kWithRegisters, arguments, deopt_mode);
 }
 
 
 void LCodeGen::RecordSafepointWithRegistersAndDoubles(
     LPointerMap* pointers,
     int arguments,
-    int deoptimization_index) {
-  RecordSafepoint(pointers, Safepoint::kWithRegistersAndDoubles, arguments,
-      deoptimization_index);
+    Safepoint::DeoptMode deopt_mode) {
+  RecordSafepoint(
+      pointers, Safepoint::kWithRegistersAndDoubles, arguments, deopt_mode);
 }
 
 
@@ -832,12 +791,6 @@
     LParallelMove* move = gap->GetParallelMove(inner_pos);
     if (move != NULL) DoParallelMove(move);
   }
-
-  LInstruction* next = GetNextInstruction();
-  if (next != NULL && next->IsLazyBailout()) {
-    int pc = masm()->pc_offset();
-    safepoints_.SetPcAfterGap(pc);
-  }
 }
 
 
@@ -1145,7 +1098,7 @@
   __ CallStub(&stub);
   RecordSafepointWithRegistersAndDoubles(instr->pointer_map(),
                                          0,
-                                         Safepoint::kNoDeoptimizationIndex);
+                                         Safepoint::kNoLazyDeopt);
   // Overwrite the stored value of r0 with the result of the stub.
   __ StoreToSafepointRegistersAndDoublesSlot(r0, r0);
 }
@@ -2062,7 +2015,7 @@
                                   LInstanceOfKnownGlobal* instr)
         : LDeferredCode(codegen), instr_(instr) { }
     virtual void Generate() {
-      codegen()->DoDeferredLInstanceOfKnownGlobal(instr_, &map_check_);
+      codegen()->DoDeferredInstanceOfKnownGlobal(instr_, &map_check_);
     }
     virtual LInstruction* instr() { return instr_; }
     Label* map_check() { return &map_check_; }
@@ -2129,8 +2082,8 @@
 }
 
 
-void LCodeGen::DoDeferredLInstanceOfKnownGlobal(LInstanceOfKnownGlobal* instr,
-                                                Label* map_check) {
+void LCodeGen::DoDeferredInstanceOfKnownGlobal(LInstanceOfKnownGlobal* instr,
+                                               Label* map_check) {
   Register result = ToRegister(instr->result());
   ASSERT(result.is(r0));
 
@@ -2162,6 +2115,9 @@
                   RelocInfo::CODE_TARGET,
                   instr,
                   RECORD_SAFEPOINT_WITH_REGISTERS_AND_NO_ARGUMENTS);
+  ASSERT(instr->HasDeoptimizationEnvironment());
+  LEnvironment* env = instr->deoptimization_environment();
+  safepoints_.RecordLazyDeoptimizationIndex(env->deoptimization_index());
   // Put the result value into the result register slot and
   // restore all registers.
   __ StoreToSafepointRegisterSlot(result, result);
@@ -2778,12 +2734,9 @@
   __ bind(&invoke);
   ASSERT(instr->HasPointerMap() && instr->HasDeoptimizationEnvironment());
   LPointerMap* pointers = instr->pointer_map();
-  LEnvironment* env = instr->deoptimization_environment();
   RecordPosition(pointers->position());
-  RegisterEnvironmentForDeoptimization(env);
-  SafepointGenerator safepoint_generator(this,
-                                         pointers,
-                                         env->deoptimization_index());
+  SafepointGenerator safepoint_generator(
+      this, pointers, Safepoint::kLazyDeopt);
   // The number of arguments is stored in receiver which is r0, as expected
   // by InvokeFunction.
   v8::internal::ParameterCount actual(receiver);
@@ -2865,7 +2818,7 @@
   __ Call(ip);
 
   // Setup deoptimization.
-  RegisterLazyDeoptimization(instr, RECORD_SIMPLE_SAFEPOINT);
+  RecordSafepointWithLazyDeopt(instr, RECORD_SIMPLE_SAFEPOINT);
 
   // Restore context.
   __ ldr(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
@@ -3230,10 +3183,8 @@
   ASSERT(instr->HasPointerMap());
   ASSERT(instr->HasDeoptimizationEnvironment());
   LPointerMap* pointers = instr->pointer_map();
-  LEnvironment* env = instr->deoptimization_environment();
   RecordPosition(pointers->position());
-  RegisterEnvironmentForDeoptimization(env);
-  SafepointGenerator generator(this, pointers, env->deoptimization_index());
+  SafepointGenerator generator(this, pointers, Safepoint::kLazyDeopt);
   ParameterCount count(instr->arity());
   __ InvokeFunction(r1, count, CALL_FUNCTION, generator, CALL_AS_METHOD);
   __ ldr(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
@@ -4558,8 +4509,10 @@
 
 
 void LCodeGen::DoLazyBailout(LLazyBailout* instr) {
-  // No code for lazy bailout instruction. Used to capture environment after a
-  // call for populating the safepoint data with deoptimization data.
+  ASSERT(instr->HasEnvironment());
+  LEnvironment* env = instr->environment();
+  RegisterEnvironmentForDeoptimization(env, Safepoint::kLazyDeopt);
+  safepoints_.RecordLazyDeoptimizationIndex(env->deoptimization_index());

[Vyacheslav Egorov (Chromium), 2011/11/15 12:03:56]

I think it should emit nop padding (the one removed from SafepointGenerator).

[fschneider, 2011/11/15 13:35:24]

Done.

 }
 
 
@@ -4576,12 +4529,9 @@
   __ Push(object, key, strict);
   ASSERT(instr->HasPointerMap() && instr->HasDeoptimizationEnvironment());
   LPointerMap* pointers = instr->pointer_map();
-  LEnvironment* env = instr->deoptimization_environment();
   RecordPosition(pointers->position());
-  RegisterEnvironmentForDeoptimization(env);
-  SafepointGenerator safepoint_generator(this,
-                                         pointers,
-                                         env->deoptimization_index());
+  SafepointGenerator safepoint_generator(
+      this, pointers, Safepoint::kLazyDeopt);
   __ InvokeBuiltin(Builtins::DELETE, CALL_FUNCTION, safepoint_generator);
 }
 
@@ -4592,27 +4542,20 @@
   __ Push(key, obj);
   ASSERT(instr->HasPointerMap() && instr->HasDeoptimizationEnvironment());
   LPointerMap* pointers = instr->pointer_map();
-  LEnvironment* env = instr->deoptimization_environment();
   RecordPosition(pointers->position());
-  RegisterEnvironmentForDeoptimization(env);
-  SafepointGenerator safepoint_generator(this,
-                                         pointers,
-                                         env->deoptimization_index());
+  SafepointGenerator safepoint_generator(this, pointers, Safepoint::kLazyDeopt);
   __ InvokeBuiltin(Builtins::IN, CALL_FUNCTION, safepoint_generator);
 }
 
 
 void LCodeGen::DoDeferredStackCheck(LStackCheck* instr) {
-  {
-    PushSafepointRegistersScope scope(this, Safepoint::kWithRegisters);
-    __ CallRuntimeSaveDoubles(Runtime::kStackGuard);
-    RegisterLazyDeoptimization(
-        instr, RECORD_SAFEPOINT_WITH_REGISTERS_AND_NO_ARGUMENTS);
-  }
-
-  // The gap code includes the restoring of the safepoint registers.
-  int pc = masm()->pc_offset();
-  safepoints_.SetPcAfterGap(pc);
+  PushSafepointRegistersScope scope(this, Safepoint::kWithRegisters);
+  __ CallRuntimeSaveDoubles(Runtime::kStackGuard);
+  RecordSafepointWithLazyDeopt(
+      instr, RECORD_SAFEPOINT_WITH_REGISTERS_AND_NO_ARGUMENTS);
+  ASSERT(instr->HasEnvironment());
+  LEnvironment* env = instr->environment();
+  safepoints_.RecordLazyDeoptimizationIndex(env->deoptimization_index());
 }
 
 
@@ -4627,6 +4570,8 @@
     LStackCheck* instr_;
   };
 
+  ASSERT(instr->HasEnvironment());
+  LEnvironment* env = instr->environment();
   if (instr->hydrogen()->is_function_entry()) {
     // Perform stack overflow check.
     Label done;
@@ -4636,6 +4581,8 @@
     StackCheckStub stub;
     CallCode(stub.GetCode(), RelocInfo::CODE_TARGET, instr);
     __ bind(&done);
+    RegisterEnvironmentForDeoptimization(env, Safepoint::kLazyDeopt);
+    safepoints_.RecordLazyDeoptimizationIndex(env->deoptimization_index());
   } else {
     ASSERT(instr->hydrogen()->is_backwards_branch());
     // Perform stack overflow check if this goto needs it before jumping.
@@ -4646,6 +4593,10 @@
     __ b(lo, deferred_stack_check->entry());
     __ bind(instr->done_label());
     deferred_stack_check->SetExit(instr->done_label());
+    RegisterEnvironmentForDeoptimization(env, Safepoint::kLazyDeopt);
+    // Don't record a deoptimization index for the safepoint here.
+    // This will be done explicitly when emitting call and the safepoint in
+    // the deferred code.
   }
 }
 
@@ -4661,7 +4612,7 @@
   // If the environment were already registered, we would have no way of
   // backpatching it with the spill slot operands.
   ASSERT(!environment->HasBeenRegistered());
-  RegisterEnvironmentForDeoptimization(environment);
+  RegisterEnvironmentForDeoptimization(environment, Safepoint::kNoLazyDeopt);
   ASSERT(osr_pc_offset_ == -1);
   osr_pc_offset_ = masm()->pc_offset();
 }