Remove some leftovers of full-codegen's generators implementation.

TBR=littledan@chromium.org
BUG=

Review-Url: https://codereview.chromium.org/2517143003
Cr-Commit-Position: refs/heads/master@{#41180}

src/arm/assembler-arm.h

@@ -1395,9 +1395,6 @@ class Assembler : public AssemblerBase {
 
   // Debugging
 
-  // Mark generator continuation.
-  void RecordGeneratorContinuation();
-
   // Mark address of a debug break slot.
   void RecordDebugBreakSlot(RelocInfo::Mode mode);
 

src/arm64/assembler-arm64.cc

@@ -2950,15 +2950,13 @@ void Assembler::RecordRelocInfo(RelocInfo::Mode rmode, intptr_t data) {
       (rmode == RelocInfo::CONST_POOL) || (rmode == RelocInfo::VENEER_POOL) ||
       (rmode == RelocInfo::DEOPT_SCRIPT_OFFSET) ||
       (rmode == RelocInfo::DEOPT_INLINING_ID) ||
-      (rmode == RelocInfo::DEOPT_REASON) || (rmode == RelocInfo::DEOPT_ID) ||
-      (rmode == RelocInfo::GENERATOR_CONTINUATION)) {
+      (rmode == RelocInfo::DEOPT_REASON) || (rmode == RelocInfo::DEOPT_ID)) {
     // Adjust code for new modes.
     DCHECK(RelocInfo::IsDebugBreakSlot(rmode) || RelocInfo::IsComment(rmode) ||
            RelocInfo::IsDeoptReason(rmode) || RelocInfo::IsDeoptId(rmode) ||
            RelocInfo::IsDeoptPosition(rmode) ||
            RelocInfo::IsInternalReference(rmode) ||
-           RelocInfo::IsConstPool(rmode) || RelocInfo::IsVeneerPool(rmode) ||
-           RelocInfo::IsGeneratorContinuation(rmode));
+           RelocInfo::IsConstPool(rmode) || RelocInfo::IsVeneerPool(rmode));
     // These modes do not need an entry in the constant pool.
   } else {
     constpool_.RecordEntry(data, rmode);

src/arm64/assembler-arm64.h

@@ -938,9 +938,6 @@ class Assembler : public AssemblerBase {
 
   int buffer_space() const;
 
-  // Mark generator continuation.
-  void RecordGeneratorContinuation();
-
   // Mark address of a debug break slot.
   void RecordDebugBreakSlot(RelocInfo::Mode mode);
 

src/assembler.cc

@@ -782,8 +782,6 @@ const char* RelocInfo::RelocModeName(RelocInfo::Mode rmode) {
       return "debug break slot at tail call";
     case CODE_AGE_SEQUENCE:
       return "code age sequence";
-    case GENERATOR_CONTINUATION:
-      return "generator continuation";
     case WASM_MEMORY_REFERENCE:
       return "wasm memory reference";
     case WASM_MEMORY_SIZE_REFERENCE:
@@ -884,7 +882,6 @@ void RelocInfo::Verify(Isolate* isolate) {
     case DEBUG_BREAK_SLOT_AT_RETURN:
     case DEBUG_BREAK_SLOT_AT_CALL:
     case DEBUG_BREAK_SLOT_AT_TAIL_CALL:
-    case GENERATOR_CONTINUATION:
     case WASM_MEMORY_REFERENCE:
     case WASM_MEMORY_SIZE_REFERENCE:
     case WASM_GLOBAL_REFERENCE:
@@ -1914,12 +1911,6 @@ void Assembler::RecordComment(const char* msg) {
 }
 
 
-void Assembler::RecordGeneratorContinuation() {
-  EnsureSpace ensure_space(this);
-  RecordRelocInfo(RelocInfo::GENERATOR_CONTINUATION);
-}
-
-
 void Assembler::RecordDebugBreakSlot(RelocInfo::Mode mode) {
   EnsureSpace ensure_space(this);
   DCHECK(RelocInfo::IsDebugBreakSlot(mode));

src/assembler.h

@@ -413,9 +413,6 @@ class RelocInfo {
     // Encoded internal reference, used only on MIPS, MIPS64 and PPC.
     INTERNAL_REFERENCE_ENCODED,
 
-    // Continuation points for a generator yield.
-    GENERATOR_CONTINUATION,
-
     // Marks constant and veneer pools. Only used on ARM and ARM64.
     // They use a custom noncompact encoding.
     CONST_POOL,
@@ -524,9 +521,6 @@ class RelocInfo {
   static inline bool IsCodeAgeSequence(Mode mode) {
     return mode == CODE_AGE_SEQUENCE;
   }
-  static inline bool IsGeneratorContinuation(Mode mode) {
-    return mode == GENERATOR_CONTINUATION;
-  }
   static inline bool IsWasmMemoryReference(Mode mode) {
     return mode == WASM_MEMORY_REFERENCE;
   }

src/debug/debug.cc

@@ -1178,29 +1178,15 @@ static Address ComputeNewPcForRedirect(Code* new_code, Code* old_code,
 
 // Count the number of continuations at which the current pc offset is at.
 static int ComputeContinuationIndexFromPcOffset(Code* code, int pc_offset) {
-  DCHECK_EQ(code->kind(), Code::FUNCTION);
-  Address pc = code->instruction_start() + pc_offset;
-  int mask = RelocInfo::ModeMask(RelocInfo::GENERATOR_CONTINUATION);
-  int index = 0;
-  for (RelocIterator it(code, mask); !it.done(); it.next()) {
-    index++;
-    RelocInfo* rinfo = it.rinfo();
-    Address current_pc = rinfo->pc();
-    if (current_pc == pc) break;
-    DCHECK(current_pc < pc);
-  }
-  return index;
+  UNREACHABLE();
+  return 666;
 }
 
 
 // Find the pc offset for the given continuation index.
 static int ComputePcOffsetFromContinuationIndex(Code* code, int index) {
-  DCHECK_EQ(code->kind(), Code::FUNCTION);
-  DCHECK(code->has_debug_break_slots());
-  int mask = RelocInfo::ModeMask(RelocInfo::GENERATOR_CONTINUATION);
-  RelocIterator it(code, mask);
-  for (int i = 1; i < index; i++) it.next();
-  return static_cast<int>(it.rinfo()->pc() - code->instruction_start());
+  UNREACHABLE();
+  return 666;
 }
 
 
@@ -1293,6 +1279,7 @@ bool Debug::PrepareFunctionForBreakPoints(Handle<SharedFunctionInfo> shared) {
     HeapIterator iterator(isolate_->heap());
     HeapObject* obj;
     // Continuation from old-style generators need to be recomputed.
+    // TODO(yangguo): Remove code for old-style generators.
     bool find_resumables =
         baseline_exists && IsResumableFunction(shared->kind());
 

src/full-codegen/arm/full-codegen-arm.cc

@@ -144,8 +144,6 @@ void FullCodeGenerator::Generate() {
 
   { Comment cmnt(masm_, "[ Allocate locals");
     int locals_count = info->scope()->num_stack_slots();
-    // Generators allocate locals, if any, in context slots.
-    DCHECK(!IsGeneratorFunction(info->literal()->kind()) || locals_count == 0);
     OperandStackDepthIncrement(locals_count);
     if (locals_count > 0) {
       if (locals_count >= 128) {

src/full-codegen/arm64/full-codegen-arm64.cc

@@ -149,8 +149,6 @@ void FullCodeGenerator::Generate() {
   // Reserve space on the stack for locals.
   { Comment cmnt(masm_, "[ Allocate locals");
     int locals_count = info->scope()->num_stack_slots();
-    // Generators allocate locals, if any, in context slots.
-    DCHECK(!IsGeneratorFunction(info->literal()->kind()) || locals_count == 0);
     OperandStackDepthIncrement(locals_count);
     if (locals_count > 0) {
       if (locals_count >= 128) {

src/full-codegen/ia32/full-codegen-ia32.cc

@@ -130,8 +130,6 @@ void FullCodeGenerator::Generate() {
 
   { Comment cmnt(masm_, "[ Allocate locals");
     int locals_count = info->scope()->num_stack_slots();
-    // Generators allocate locals, if any, in context slots.
-    DCHECK(!IsGeneratorFunction(literal()->kind()) || locals_count == 0);
     OperandStackDepthIncrement(locals_count);
     if (locals_count == 1) {
       __ push(Immediate(isolate()->factory()->undefined_value()));

src/full-codegen/mips/full-codegen-mips.cc

@@ -153,8 +153,6 @@ void FullCodeGenerator::Generate() {
 
   { Comment cmnt(masm_, "[ Allocate locals");
     int locals_count = info->scope()->num_stack_slots();
-    // Generators allocate locals, if any, in context slots.
-    DCHECK(!IsGeneratorFunction(info->literal()->kind()) || locals_count == 0);
     OperandStackDepthIncrement(locals_count);
     if (locals_count > 0) {
       if (locals_count >= 128) {

src/full-codegen/mips64/full-codegen-mips64.cc

@@ -152,8 +152,6 @@ void FullCodeGenerator::Generate() {
 
   { Comment cmnt(masm_, "[ Allocate locals");
     int locals_count = info->scope()->num_stack_slots();
-    // Generators allocate locals, if any, in context slots.
-    DCHECK(!IsGeneratorFunction(info->literal()->kind()) || locals_count == 0);
     OperandStackDepthIncrement(locals_count);
     if (locals_count > 0) {
       if (locals_count >= 128) {

src/full-codegen/ppc/full-codegen-ppc.cc

@@ -152,8 +152,6 @@ void FullCodeGenerator::Generate() {
   {
     Comment cmnt(masm_, "[ Allocate locals");
     int locals_count = info->scope()->num_stack_slots();
-    // Generators allocate locals, if any, in context slots.
-    DCHECK(!IsGeneratorFunction(info->literal()->kind()) || locals_count == 0);
     OperandStackDepthIncrement(locals_count);
     if (locals_count > 0) {
       if (locals_count >= 128) {

src/full-codegen/s390/full-codegen-s390.cc

@@ -151,8 +151,6 @@ void FullCodeGenerator::Generate() {
   {
     Comment cmnt(masm_, "[ Allocate locals");
     int locals_count = info->scope()->num_stack_slots();
-    // Generators allocate locals, if any, in context slots.
-    DCHECK(!IsGeneratorFunction(info->literal()->kind()) || locals_count == 0);
     OperandStackDepthIncrement(locals_count);
     if (locals_count > 0) {
       if (locals_count >= 128) {

src/full-codegen/x64/full-codegen-x64.cc

@@ -131,8 +131,6 @@ void FullCodeGenerator::Generate() {
 
   { Comment cmnt(masm_, "[ Allocate locals");
     int locals_count = info->scope()->num_stack_slots();
-    // Generators allocate locals, if any, in context slots.
-    DCHECK(!IsGeneratorFunction(info->literal()->kind()) || locals_count == 0);
     OperandStackDepthIncrement(locals_count);
     if (locals_count == 1) {
       __ PushRoot(Heap::kUndefinedValueRootIndex);

src/full-codegen/x87/full-codegen-x87.cc

@@ -130,8 +130,6 @@ void FullCodeGenerator::Generate() {
 
   { Comment cmnt(masm_, "[ Allocate locals");
     int locals_count = info->scope()->num_stack_slots();
-    // Generators allocate locals, if any, in context slots.
-    DCHECK(!IsGeneratorFunction(literal()->kind()) || locals_count == 0);
     OperandStackDepthIncrement(locals_count);
     if (locals_count == 1) {
       __ push(Immediate(isolate()->factory()->undefined_value()));

src/ia32/assembler-ia32.h

@@ -1434,9 +1434,6 @@ class Assembler : public AssemblerBase {
     return pc_offset() - label->pos();
   }
 
-  // Mark generator continuation.
-  void RecordGeneratorContinuation();
-
   // Mark address of a debug break slot.
   void RecordDebugBreakSlot(RelocInfo::Mode mode);
 

src/mips/assembler-mips.h

@@ -1029,9 +1029,6 @@ class Assembler : public AssemblerBase {
 
   // Debugging.
 
-  // Mark generator continuation.
-  void RecordGeneratorContinuation();
-
   // Mark address of a debug break slot.
   void RecordDebugBreakSlot(RelocInfo::Mode mode);
 

src/mips64/assembler-mips64.h

@@ -1091,9 +1091,6 @@ class Assembler : public AssemblerBase {
 
   // Debugging.
 
-  // Mark generator continuation.
-  void RecordGeneratorContinuation();
-
   // Mark address of a debug break slot.
   void RecordDebugBreakSlot(RelocInfo::Mode mode);
 

src/objects.cc

@@ -19749,24 +19749,14 @@ void PropertyCell::SetValueWithInvalidation(Handle<PropertyCell> cell,
 
 int JSGeneratorObject::source_position() const {
   CHECK(is_suspended());
-  AbstractCode* code;
-  int code_offset;
-  if (function()->shared()->HasBytecodeArray()) {
-    // New-style generators.
-    DCHECK(!function()->shared()->HasBaselineCode());
-    code_offset = Smi::cast(input_or_debug_pos())->value();
-    // The stored bytecode offset is relative to a different base than what
-    // is used in the source position table, hence the subtraction.
-    code_offset -= BytecodeArray::kHeaderSize - kHeapObjectTag;
-    code = AbstractCode::cast(function()->shared()->bytecode_array());
-  } else {
-    // Old-style generators.
-    DCHECK(function()->shared()->HasBaselineCode());
-    code_offset = continuation();
-    CHECK(0 <= code_offset);
-    CHECK(code_offset < function()->code()->instruction_size());
-    code = AbstractCode::cast(function()->shared()->code());
-  }
+  DCHECK(function()->shared()->HasBytecodeArray());
+  DCHECK(!function()->shared()->HasBaselineCode());
+  int code_offset = Smi::cast(input_or_debug_pos())->value();
+  // The stored bytecode offset is relative to a different base than what
+  // is used in the source position table, hence the subtraction.
+  code_offset -= BytecodeArray::kHeaderSize - kHeapObjectTag;
+  AbstractCode* code =
+      AbstractCode::cast(function()->shared()->bytecode_array());
   return code->SourcePosition(code_offset);
 }
 

src/objects.h

@@ -8057,8 +8057,7 @@ class JSGeneratorObject: public JSObject {
 
   // [input_or_debug_pos]
   // For executing generators: the most recent input value.
-  // For suspended new-style generators: debug information (bytecode offset).
-  // For suspended old-style generators: unused.
+  // For suspended generators: debug information (bytecode offset).
   // There is currently no need to remember the most recent input value for a
   // suspended generator.
   DECL_ACCESSORS(input_or_debug_pos, Object)

src/parsing/parser.cc

@@ -2503,10 +2503,10 @@ void Parser::ReindexLiterals(const ParserFormalParameters& parameters) {
 }
 
 void Parser::PrepareGeneratorVariables(FunctionState* function_state) {
-  // For generators, allocating variables in contexts is currently a win
-  // because it minimizes the work needed to suspend and resume an
-  // activation.  The machine code produced for generators (by full-codegen)
-  // relies on this forced context allocation, but not in an essential way.
+  // For generators, allocating variables in contexts is currently a win because
+  // it minimizes the work needed to suspend and resume an activation.  The
+  // code produced for generators relies on this forced context allocation, but
+  // not in an essential way.
   scope()->ForceContextAllocation();
 
   // Calling a generator returns a generator object.  That object is stored

src/ppc/assembler-ppc.h

@@ -1188,9 +1188,6 @@ class Assembler : public AssemblerBase {
 
   // Debugging
 
-  // Mark generator continuation.
-  void RecordGeneratorContinuation();
-
   // Mark address of a debug break slot.
   void RecordDebugBreakSlot(RelocInfo::Mode mode);
 

src/s390/assembler-s390.h

@@ -1231,9 +1231,6 @@ class Assembler : public AssemblerBase {
 
   // Debugging
 
-  // Mark generator continuation.
-  void RecordGeneratorContinuation();
-
   // Mark address of a debug break slot.
   void RecordDebugBreakSlot(RelocInfo::Mode mode);
 

src/x64/assembler-x64.h

@@ -1981,9 +1981,6 @@ class Assembler : public AssemblerBase {
     return pc_offset() - label->pos();
   }
 
-  // Mark generator continuation.
-  void RecordGeneratorContinuation();
-
   // Mark address of a debug break slot.
   void RecordDebugBreakSlot(RelocInfo::Mode mode);
 

src/x87/assembler-x87.h

@@ -957,9 +957,6 @@ class Assembler : public AssemblerBase {
     return pc_offset() - label->pos();
   }
 
-  // Mark generator continuation.
-  void RecordGeneratorContinuation();
-
   // Mark address of a debug break slot.
   void RecordDebugBreakSlot(RelocInfo::Mode mode);