[deoptimizer] Add trampoline pc to the DeoptimizationInputData.

Extend the deoptimization jump-table in optimized code objects
to also contain entries for lazy deoptimization exits, and
introduce a trampoline pc in the DeoptimizationInputData,
which maps back from the return-site to the jump-table offset.

Bug: v8:6562, v8:6561
Change-Id: Id085d5467e3ceff251c2ec2768329a9e22c0aff6
Reviewed-on: https://chromium-review.googlesource.com/563403
Commit-Queue: Juliana Patricia Vicente Franco <jupvfranco@google.com>
Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46501}

src/compiler/code-generator.cc

@@ -193,7 +193,11 @@ void CodeGenerator::AssembleCode() {
   // Assemble all eager deoptimization exits.
   for (DeoptimizationExit* exit : deoptimization_exits_) {
     tasm()->bind(exit->label());
-    AssembleDeoptimizerCall(exit->deoptimization_id(), exit->pos());
+    int trampoline_pc = tasm()->pc_offset();
+    int deoptimization_id = exit->deoptimization_id();
+    DeoptimizationState* ds = deoptimization_states_[deoptimization_id];
+    ds->set_trampoline_pc(trampoline_pc);
+    AssembleDeoptimizerCall(deoptimization_id, exit->pos());
   }
 
   // Ensure there is space for lazy deoptimization in the code.
@@ -599,10 +603,11 @@ void CodeGenerator::PopulateDeoptimizationData(Handle<Code> code_object) {
   for (int i = 0; i < deopt_count; i++) {
     DeoptimizationState* deoptimization_state = deoptimization_states_[i];
     data->SetBytecodeOffset(i, deoptimization_state->bailout_id());
-    CHECK(deoptimization_states_[i]);
+    CHECK(deoptimization_state);
     data->SetTranslationIndex(
-        i, Smi::FromInt(deoptimization_states_[i]->translation_id()));
-    data->SetArgumentsStackHeight(i, Smi::kZero);
+        i, Smi::FromInt(deoptimization_state->translation_id()));
+    data->SetTrampolinePc(i,
+                          Smi::FromInt(deoptimization_state->trampoline_pc()));
     data->SetPc(i, Smi::FromInt(deoptimization_state->pc_offset()));
   }
 
@@ -641,6 +646,11 @@ void CodeGenerator::RecordCallPosition(Instruction* instr) {
     int pc_offset = tasm()->pc_offset();
     int deopt_state_id = BuildTranslation(instr, pc_offset, frame_state_offset,
                                           descriptor->state_combine());
+
+    DeoptimizationExit* const exit = new (zone())
+        DeoptimizationExit(deopt_state_id, current_source_position_);
+    deoptimization_exits_.push_back(exit);
+
     // If the pre-call frame state differs from the post-call one, produce the
     // pre-call frame state, too.
     // TODO(jarin) We might want to avoid building the pre-call frame state
@@ -978,7 +988,6 @@ void CodeGenerator::AddTranslationForOperand(Translation* translation,
   }
 }
 
-
 void CodeGenerator::MarkLazyDeoptSite() {
   last_lazy_deopt_pc_ = tasm()->pc_offset();
 }
@@ -987,6 +996,7 @@ DeoptimizationExit* CodeGenerator::AddDeoptimizationExit(
     Instruction* instr, size_t frame_state_offset) {
   int const deoptimization_id = BuildTranslation(
       instr, -1, frame_state_offset, OutputFrameStateCombine::Ignore());
+
   DeoptimizationExit* const exit = new (zone())
       DeoptimizationExit(deoptimization_id, current_source_position_);
   deoptimization_exits_.push_back(exit);
@@ -998,7 +1008,6 @@ OutOfLineCode::OutOfLineCode(CodeGenerator* gen)
   gen->ools_ = this;
 }
 
-
 OutOfLineCode::~OutOfLineCode() {}
 
 }  // namespace compiler

src/compiler/code-generator.h

@@ -282,13 +282,16 @@ class CodeGenerator final : public GapResolver::Assembler {
           translation_id_(translation_id),
           pc_offset_(pc_offset),
           kind_(kind),
-          reason_(reason) {}
+          reason_(reason),
+          trampoline_pc_(-1) {}
 
     BailoutId bailout_id() const { return bailout_id_; }
     int translation_id() const { return translation_id_; }
     int pc_offset() const { return pc_offset_; }
     DeoptimizeKind kind() const { return kind_; }
     DeoptimizeReason reason() const { return reason_; }
+    int trampoline_pc() { return trampoline_pc_; }
+    void set_trampoline_pc(int t_pc) { trampoline_pc_ = t_pc; }
 
    private:
     BailoutId bailout_id_;
@@ -296,6 +299,7 @@ class CodeGenerator final : public GapResolver::Assembler {
     int pc_offset_;
     DeoptimizeKind kind_;
     DeoptimizeReason reason_;
+    int trampoline_pc_;
   };
 
   struct HandlerInfo {

src/deoptimizer.cc

@@ -421,6 +421,7 @@ void Deoptimizer::DeoptimizeFunction(JSFunction* function, Code* code) {
   TimerEventScope<TimerEventDeoptimizeCode> timer(isolate);
   TRACE_EVENT0("v8", "V8.DeoptimizeCode");
   if (code == nullptr) code = function->code();
+
   if (code->kind() == Code::OPTIMIZED_FUNCTION) {
     // Mark the code for deoptimization and unlink any functions that also
     // refer to that code. The code cannot be shared across native contexts,
@@ -1064,10 +1065,7 @@ void Deoptimizer::DoComputeInterpretedFrame(TranslatedFrame* translated_frame,
     intptr_t context_value = reinterpret_cast<intptr_t>(Smi::kZero);
     Register context_reg = JavaScriptFrame::context_register();
     output_frame->SetRegister(context_reg.code(), context_value);
-  }
-
     // Set the continuation for the topmost frame.
-  if (is_topmost) {
     Code* continuation = builtins->builtin(Builtins::kNotifyDeoptimized);
     if (bailout_type_ == LAZY) {
       continuation = builtins->builtin(Builtins::kNotifyLazyDeoptimized);
@@ -2035,8 +2033,8 @@ unsigned Deoptimizer::ComputeInputFrameSize() const {
   unsigned result = fixed_size_above_fp + fp_to_sp_delta_;
   if (compiled_code_->kind() == Code::OPTIMIZED_FUNCTION) {
     unsigned stack_slots = compiled_code_->stack_slots();
-    unsigned outgoing_size =
-        ComputeOutgoingArgumentSize(compiled_code_, bailout_id_);
+    unsigned outgoing_size = 0;
+    //        ComputeOutgoingArgumentSize(compiled_code_, bailout_id_);
     CHECK_EQ(fixed_size_above_fp + (stack_slots * kPointerSize) -
                  CommonFrameConstants::kFixedFrameSizeAboveFp + outgoing_size,
              result);
@@ -2066,16 +2064,6 @@ unsigned Deoptimizer::ComputeIncomingArgumentSize(SharedFunctionInfo* shared) {
   return (shared->internal_formal_parameter_count() + 1) * kPointerSize;
 }
 
-
-// static
-unsigned Deoptimizer::ComputeOutgoingArgumentSize(Code* code,
-                                                  unsigned bailout_id) {
-  DeoptimizationInputData* data =
-      DeoptimizationInputData::cast(code->deoptimization_data());
-  unsigned height = data->ArgumentsStackHeight(bailout_id)->value();
-  return height * kPointerSize;
-}
-
 void Deoptimizer::EnsureCodeForDeoptimizationEntry(Isolate* isolate,
                                                    BailoutType type,
                                                    int max_entry_id) {

src/objects-inl.h

@@ -2618,7 +2618,7 @@ DEFINE_DEOPT_ELEMENT_ACCESSORS(InliningPositions, PodArray<InliningPosition>)
 
 DEFINE_DEOPT_ENTRY_ACCESSORS(BytecodeOffsetRaw, Smi)
 DEFINE_DEOPT_ENTRY_ACCESSORS(TranslationIndex, Smi)
-DEFINE_DEOPT_ENTRY_ACCESSORS(ArgumentsStackHeight, Smi)
+DEFINE_DEOPT_ENTRY_ACCESSORS(TrampolinePc, Smi)
 DEFINE_DEOPT_ENTRY_ACCESSORS(Pc, Smi)
 
 BailoutId DeoptimizationInputData::BytecodeOffset(int i) {

src/objects.cc

@@ -14310,26 +14310,26 @@ void DeoptimizationInputData::DeoptimizationInputDataPrint(
   int deopt_count = DeoptCount();
   os << "Deoptimization Input Data (deopt points = " << deopt_count << ")\n";
   if (0 != deopt_count) {
-    os << " index  bytecode-offset    argc     pc";
+    os << " index  bytecode-offset  trampoline_pc     pc";
     if (FLAG_print_code_verbose) os << "  commands";
     os << "\n";
   }
   for (int i = 0; i < deopt_count; i++) {
     os << std::setw(6) << i << "  " << std::setw(15)
-       << BytecodeOffset(i).ToInt() << "  " << std::setw(6)
-       << ArgumentsStackHeight(i)->value() << " ";
+       << BytecodeOffset(i).ToInt() << "  " << std::setw(13) << std::hex
+       << TrampolinePc(i)->value() << " " << std::setw(6);
     int pc_value = Pc(i)->value();
     if (pc_value != -1) {
-      os << std::setw(6) << std::hex << pc_value;
+      os << pc_value << std::dec;
     } else {
-      os << std::setw(6) << "NA";
+      os << "NA";
     }
-    os << std::dec;
 
     if (!FLAG_print_code_verbose) {
       os << "\n";
       continue;
     }
+
     // Print details of the frame translation.
     int translation_index = TranslationIndex(i)->value();
     TranslationIterator iterator(TranslationByteArray(), translation_index);
@@ -14345,7 +14345,7 @@ void DeoptimizationInputData::DeoptimizationInputDataPrint(
     while (iterator.HasNext() &&
            Translation::BEGIN !=
            (opcode = static_cast<Translation::Opcode>(iterator.Next()))) {
-      os << std::setw(40) << "    " << Translation::StringFor(opcode) << " ";
+      os << std::setw(47) << "    " << Translation::StringFor(opcode) << " ";
 
       switch (opcode) {
         case Translation::BEGIN:

src/objects.h

@@ -3481,7 +3481,7 @@ class DeoptimizationInputData: public FixedArray {
   // Offsets of deopt entry elements relative to the start of the entry.
   static const int kBytecodeOffsetRawOffset = 0;
   static const int kTranslationIndexOffset = 1;
-  static const int kArgumentsStackHeightOffset = 2;
+  static const int kTrampolinePcOffset = 2;
   static const int kPcOffset = 3;
   static const int kDeoptEntrySize = 4;
 
@@ -3509,7 +3509,7 @@ class DeoptimizationInputData: public FixedArray {
 
   DECL_ENTRY_ACCESSORS(BytecodeOffsetRaw, Smi)
   DECL_ENTRY_ACCESSORS(TranslationIndex, Smi)
-  DECL_ENTRY_ACCESSORS(ArgumentsStackHeight, Smi)
+  DECL_ENTRY_ACCESSORS(TrampolinePc, Smi)
   DECL_ENTRY_ACCESSORS(Pc, Smi)
 
 #undef DECL_ENTRY_ACCESSORS