[interpreter] Merge {OsrPoll} with {Jump} bytecode.

This introduces a new {JumpLoop} bytecode to combine the OSR polling
mechanism modeled by {OsrPoll} with the actual {Jump} performing the
backwards branch. This reduces the overall size and also avoids one
additional dispatch. It also makes sure that OSR polling is only done
within real loops.

R=rmcilroy@chromium.org
BUG=v8:4764

Review-Url: https://codereview.chromium.org/2331033002
Cr-Commit-Position: refs/heads/master@{#39384}

src/compiler/bytecode-graph-builder.cc

@@ -1616,14 +1616,14 @@ void BytecodeGraphBuilder::VisitJumpIfUndefinedConstant() {
   BuildJumpIfEqual(jsgraph()->UndefinedConstant());
 }
 
+void BytecodeGraphBuilder::VisitJumpLoop() { BuildJump(); }
+
 void BytecodeGraphBuilder::VisitStackCheck() {
   FrameStateBeforeAndAfter states(this);
   Node* node = NewNode(javascript()->StackCheck());
   environment()->RecordAfterState(node, &states);
 }
 
-void BytecodeGraphBuilder::VisitOsrPoll() {}
-
 void BytecodeGraphBuilder::VisitReturn() {
   BuildLoopExitsForFunctionExit();
   Node* control =

src/interpreter/bytecode-array-builder.cc

@@ -452,43 +452,54 @@ BytecodeArrayBuilder& BytecodeArrayBuilder::Bind(const BytecodeLabel& target,
   return *this;
 }
 
-BytecodeArrayBuilder& BytecodeArrayBuilder::OutputJump(Bytecode jump_bytecode,
+BytecodeArrayBuilder& BytecodeArrayBuilder::OutputJump(BytecodeNode* node,
                                                        BytecodeLabel* label) {
-  BytecodeNode node(jump_bytecode, 0);
-  AttachSourceInfo(&node);
-  pipeline_->WriteJump(&node, label);
+  AttachSourceInfo(node);
+  pipeline_->WriteJump(node, label);
   LeaveBasicBlock();
   return *this;
 }
 
 BytecodeArrayBuilder& BytecodeArrayBuilder::Jump(BytecodeLabel* label) {
-  return OutputJump(Bytecode::kJump, label);
+  BytecodeNode node(Bytecode::kJump, 0);
+  return OutputJump(&node, label);
 }
 
 BytecodeArrayBuilder& BytecodeArrayBuilder::JumpIfTrue(BytecodeLabel* label) {
   // The peephole optimizer attempts to simplify JumpIfToBooleanTrue
   // to JumpIfTrue.
-  return OutputJump(Bytecode::kJumpIfToBooleanTrue, label);
+  BytecodeNode node(Bytecode::kJumpIfToBooleanTrue, 0);
+  return OutputJump(&node, label);
 }
 
 BytecodeArrayBuilder& BytecodeArrayBuilder::JumpIfFalse(BytecodeLabel* label) {
   // The peephole optimizer attempts to simplify JumpIfToBooleanFalse
   // to JumpIfFalse.
-  return OutputJump(Bytecode::kJumpIfToBooleanFalse, label);
+  BytecodeNode node(Bytecode::kJumpIfToBooleanFalse, 0);
+  return OutputJump(&node, label);
 }
 
 BytecodeArrayBuilder& BytecodeArrayBuilder::JumpIfNull(BytecodeLabel* label) {
-  return OutputJump(Bytecode::kJumpIfNull, label);
+  BytecodeNode node(Bytecode::kJumpIfNull, 0);
+  return OutputJump(&node, label);
 }
 
 BytecodeArrayBuilder& BytecodeArrayBuilder::JumpIfUndefined(
     BytecodeLabel* label) {
-  return OutputJump(Bytecode::kJumpIfUndefined, label);
+  BytecodeNode node(Bytecode::kJumpIfUndefined, 0);
+  return OutputJump(&node, label);
 }
 
 BytecodeArrayBuilder& BytecodeArrayBuilder::JumpIfNotHole(
     BytecodeLabel* label) {
-  return OutputJump(Bytecode::kJumpIfNotHole, label);
+  BytecodeNode node(Bytecode::kJumpIfNotHole, 0);
+  return OutputJump(&node, label);
+}
+
+BytecodeArrayBuilder& BytecodeArrayBuilder::JumpLoop(BytecodeLabel* label,
+                                                     int loop_depth) {
+  BytecodeNode node(Bytecode::kJumpLoop, 0, UnsignedOperand(loop_depth));
+  return OutputJump(&node, label);
 }
 
 BytecodeArrayBuilder& BytecodeArrayBuilder::StackCheck(int position) {
@@ -509,11 +520,6 @@ BytecodeArrayBuilder& BytecodeArrayBuilder::StackCheck(int position) {
   return *this;
 }
 
-BytecodeArrayBuilder& BytecodeArrayBuilder::OsrPoll(int loop_depth) {
-  Output(Bytecode::kOsrPoll, UnsignedOperand(loop_depth));
-  return *this;
-}
-
 BytecodeArrayBuilder& BytecodeArrayBuilder::Throw() {
   Output(Bytecode::kThrow);
   return *this;

src/interpreter/bytecode-array-builder.h

@@ -254,11 +254,10 @@ class BytecodeArrayBuilder final : public ZoneObject {
   BytecodeArrayBuilder& JumpIfNotHole(BytecodeLabel* label);
   BytecodeArrayBuilder& JumpIfNull(BytecodeLabel* label);
   BytecodeArrayBuilder& JumpIfUndefined(BytecodeLabel* label);
+  BytecodeArrayBuilder& JumpLoop(BytecodeLabel* label, int loop_depth);
 
   BytecodeArrayBuilder& StackCheck(int position);
 
-  BytecodeArrayBuilder& OsrPoll(int loop_depth);
-
   BytecodeArrayBuilder& Throw();
   BytecodeArrayBuilder& ReThrow();
   BytecodeArrayBuilder& Return();
@@ -352,8 +351,7 @@ class BytecodeArrayBuilder final : public ZoneObject {
   void Output(Bytecode bytecode, uint32_t operand0);
   void Output(Bytecode bytecode);
 
-  BytecodeArrayBuilder& OutputJump(Bytecode jump_bytecode,
-                                   BytecodeLabel* label);
+  BytecodeArrayBuilder& OutputJump(BytecodeNode* node, BytecodeLabel* label);
 
   bool RegisterIsValid(Register reg) const;
   bool OperandsAreValid(Bytecode bytecode, int operand_count,

src/interpreter/bytecode-array-writer.cc

@@ -357,7 +357,8 @@ void BytecodeArrayWriter::EmitJump(BytecodeNode* node, BytecodeLabel* label) {
       DCHECK_LE(delta, 0);
       delta -= 1;
     }
-    node->set_bytecode(node->bytecode(), delta);
+    DCHECK_EQ(Bytecode::kJumpLoop, node->bytecode());
+    node->set_bytecode(node->bytecode(), delta, node->operand(1));
   } else {
     // The label has not yet been bound so this is a forward reference
     // that will be patched when the label is bound. We create a
@@ -369,6 +370,7 @@ void BytecodeArrayWriter::EmitJump(BytecodeNode* node, BytecodeLabel* label) {
     label->set_referrer(current_offset);
     OperandSize reserved_operand_size =
         constant_array_builder()->CreateReservedEntry();
+    DCHECK_NE(Bytecode::kJumpLoop, node->bytecode());
     switch (reserved_operand_size) {
       case OperandSize::kNone:
         UNREACHABLE();

src/interpreter/bytecode-generator.cc

@@ -826,14 +826,6 @@ void BytecodeGenerator::VisitIterationHeader(IterationStatement* stmt,
 
   loop_builder->LoopHeader(&resume_points_in_loop);
 
-  // Insert an explicit {OsrPoll} right after the loop header, to trigger
-  // on-stack replacement when armed for the given loop nesting depth.
-  if (FLAG_ignition_osr) {
-    // TODO(4764): Merge this with another bytecode (e.g. {Jump} back edge).
-    int level = Min(loop_depth_, AbstractCode::kMaxLoopNestingMarker - 1);
-    builder()->OsrPoll(level);
-  }
-
   if (stmt->yield_count() > 0) {
     // If we are not resuming, fall through to loop body.
     // If we are resuming, perform state dispatch.
@@ -1170,13 +1162,16 @@ void BytecodeGenerator::VisitDoWhileStatement(DoWhileStatement* stmt) {
   } else if (stmt->cond()->ToBooleanIsTrue()) {
     VisitIterationHeader(stmt, &loop_builder);
     VisitIterationBody(stmt, &loop_builder);
-    loop_builder.JumpToHeader();
+    loop_builder.JumpToHeader(loop_depth_);
   } else {
     VisitIterationHeader(stmt, &loop_builder);
     VisitIterationBody(stmt, &loop_builder);
     builder()->SetExpressionAsStatementPosition(stmt->cond());
-    VisitForTest(stmt->cond(), loop_builder.header_labels(),
-                 loop_builder.break_labels(), TestFallthrough::kElse);
+    BytecodeLabels loop_backbranch(zone());
+    VisitForTest(stmt->cond(), &loop_backbranch, loop_builder.break_labels(),
+                 TestFallthrough::kThen);
+    loop_backbranch.Bind(builder());
+    loop_builder.JumpToHeader(loop_depth_);
   }
   loop_builder.EndLoop();
 }
@@ -1197,7 +1192,7 @@ void BytecodeGenerator::VisitWhileStatement(WhileStatement* stmt) {
     loop_body.Bind(builder());
   }
   VisitIterationBody(stmt, &loop_builder);
-  loop_builder.JumpToHeader();
+  loop_builder.JumpToHeader(loop_depth_);
   loop_builder.EndLoop();
 }
 
@@ -1225,7 +1220,7 @@ void BytecodeGenerator::VisitForStatement(ForStatement* stmt) {
     builder()->SetStatementPosition(stmt->next());
     Visit(stmt->next());
   }
-  loop_builder.JumpToHeader();
+  loop_builder.JumpToHeader(loop_depth_);
   loop_builder.EndLoop();
 }
 
@@ -1346,7 +1341,7 @@ void BytecodeGenerator::VisitForInStatement(ForInStatement* stmt) {
   VisitIterationBody(stmt, &loop_builder);
   builder()->ForInStep(index);
   builder()->StoreAccumulatorInRegister(index);
-  loop_builder.JumpToHeader();
+  loop_builder.JumpToHeader(loop_depth_);
   loop_builder.EndLoop();
   builder()->Bind(&subject_null_label);
   builder()->Bind(&subject_undefined_label);
@@ -1366,7 +1361,7 @@ void BytecodeGenerator::VisitForOfStatement(ForOfStatement* stmt) {
 
   VisitForEffect(stmt->assign_each());
   VisitIterationBody(stmt, &loop_builder);
-  loop_builder.JumpToHeader();
+  loop_builder.JumpToHeader(loop_depth_);
   loop_builder.EndLoop();
 }
 

src/interpreter/bytecodes.cc

@@ -407,7 +407,8 @@ bool Bytecodes::IsConditionalJump(Bytecode bytecode) {
 
 // static
 bool Bytecodes::IsJumpImmediate(Bytecode bytecode) {
-  return bytecode == Bytecode::kJump || IsConditionalJumpImmediate(bytecode);
+  return bytecode == Bytecode::kJump || bytecode == Bytecode::kJumpLoop ||
+         IsConditionalJumpImmediate(bytecode);
 }
 
 

src/interpreter/bytecodes.h

@@ -273,6 +273,7 @@ namespace interpreter {
   V(JumpIfUndefinedConstant, AccumulatorUse::kRead, OperandType::kIdx)         \
   V(JumpIfNotHole, AccumulatorUse::kRead, OperandType::kImm)                   \
   V(JumpIfNotHoleConstant, AccumulatorUse::kRead, OperandType::kIdx)           \
+  V(JumpLoop, AccumulatorUse::kNone, OperandType::kImm, OperandType::kImm)     \
                                                                                \
   /* Complex flow control For..in */                                           \
   V(ForInPrepare, AccumulatorUse::kNone, OperandType::kReg,                    \
@@ -286,9 +287,6 @@ namespace interpreter {
   /* Perform a stack guard check */                                            \
   V(StackCheck, AccumulatorUse::kNone)                                         \
                                                                                \
-  /* Perform a check to trigger on-stack replacement */                        \
-  V(OsrPoll, AccumulatorUse::kNone, OperandType::kImm)                         \
-                                                                               \
   /* Non-local flow control */                                                 \
   V(Throw, AccumulatorUse::kRead)                                              \
   V(ReThrow, AccumulatorUse::kRead)                                            \

src/interpreter/control-flow-builders.cc

@@ -60,18 +60,14 @@ void LoopBuilder::LoopHeader(ZoneVector<BytecodeLabel>* additional_labels) {
   }
 }
 
-void LoopBuilder::JumpToHeader() {
+void LoopBuilder::JumpToHeader(int loop_depth) {
+  // Pass the proper loop nesting level to the backwards branch, to trigger
+  // on-stack replacement when armed for the given loop nesting depth.
+  int level = Min(loop_depth, AbstractCode::kMaxLoopNestingMarker - 1);
   // Loop must have closed form, i.e. all loop elements are within the loop,
   // the loop header precedes the body and next elements in the loop.
   DCHECK(loop_header_.is_bound());
-  builder()->Jump(&loop_header_);
-}
-
-void LoopBuilder::JumpToHeaderIfTrue() {
-  // Loop must have closed form, i.e. all loop elements are within the loop,
-  // the loop header precedes the body and next elements in the loop.
-  DCHECK(loop_header_.is_bound());
-  builder()->JumpIfTrue(&loop_header_);
+  builder()->JumpLoop(&loop_header_, level);
 }
 
 void LoopBuilder::EndLoop() {

src/interpreter/control-flow-builders.h

@@ -86,8 +86,7 @@ class LoopBuilder final : public BreakableControlFlowBuilder {
   ~LoopBuilder();
 
   void LoopHeader(ZoneVector<BytecodeLabel>* additional_labels);
-  void JumpToHeader();
-  void JumpToHeaderIfTrue();
+  void JumpToHeader(int loop_depth);
   void BindContinueTarget();
   void EndLoop();
 
@@ -99,9 +98,6 @@ class LoopBuilder final : public BreakableControlFlowBuilder {
   void ContinueIfUndefined() { EmitJumpIfUndefined(&continue_labels_); }
   void ContinueIfNull() { EmitJumpIfNull(&continue_labels_); }
 
-  BytecodeLabels* header_labels() { return &header_labels_; }
-  BytecodeLabels* continue_labels() { return &continue_labels_; }
-
  private:
   BytecodeLabel loop_header_;
 

src/interpreter/interpreter-assembler.cc

@@ -938,6 +938,9 @@ Node* InterpreterAssembler::CallRuntimeN(Node* function_id, Node* context,
 }
 
 void InterpreterAssembler::UpdateInterruptBudget(Node* weight) {
+  // TODO(rmcilroy): It might be worthwhile to only update the budget for
+  // backwards branches. Those are distinguishable by the {JumpLoop} bytecode.
+
   Label ok(this), interrupt_check(this, Label::kDeferred), end(this);
   Node* budget_offset =
       IntPtrConstant(BytecodeArray::kInterruptBudgetOffset - kHeapObjectTag);

src/interpreter/interpreter.cc

@@ -1854,6 +1854,35 @@ void Interpreter::DoJumpIfNotHoleConstant(InterpreterAssembler* assembler) {
   __ JumpIfWordNotEqual(accumulator, the_hole_value, relative_jump);
 }
 
+// JumpLoop <imm> <loop_depth>
+//
+// Jump by number of bytes represented by the immediate operand |imm|. Also
+// performs a loop nesting check and potentially triggers OSR in case the
+// current OSR level matches (or exceeds) the specified |loop_depth|.
+void Interpreter::DoJumpLoop(InterpreterAssembler* assembler) {
+  Node* relative_jump = __ BytecodeOperandImm(0);
+  Node* loop_depth = __ BytecodeOperandImm(1);
+  Node* osr_level = __ LoadOSRNestingLevel();
+
+  // Check if OSR points at the given {loop_depth} are armed by comparing it to
+  // the current {osr_level} loaded from the header of the BytecodeArray.
+  Label ok(assembler), osr_armed(assembler, Label::kDeferred);
+  Node* condition = __ Int32GreaterThanOrEqual(loop_depth, osr_level);
+  __ Branch(condition, &ok, &osr_armed);
+
+  __ Bind(&ok);
+  __ Jump(relative_jump);
+
+  __ Bind(&osr_armed);
+  {
+    Callable callable = CodeFactory::InterpreterOnStackReplacement(isolate_);
+    Node* target = __ HeapConstant(callable.code());
+    Node* context = __ GetContext();
+    __ CallStub(callable.descriptor(), target, context);
+    __ Jump(relative_jump);
+  }
+}
+
 // CreateRegExpLiteral <pattern_idx> <literal_idx> <flags>
 //
 // Creates a regular expression literal for literal index <literal_idx> with
@@ -2124,32 +2153,6 @@ void Interpreter::DoStackCheck(InterpreterAssembler* assembler) {
   }
 }
 
-// OsrPoll <loop_depth>
-//
-// Performs a loop nesting check and potentially triggers OSR.
-void Interpreter::DoOsrPoll(InterpreterAssembler* assembler) {
-  Node* loop_depth = __ BytecodeOperandImm(0);
-  Node* osr_level = __ LoadOSRNestingLevel();
-
-  // Check if OSR points at the given {loop_depth} are armed by comparing it to
-  // the current {osr_level} loaded from the header of the BytecodeArray.
-  Label ok(assembler), osr_armed(assembler, Label::kDeferred);
-  Node* condition = __ Int32GreaterThanOrEqual(loop_depth, osr_level);
-  __ Branch(condition, &ok, &osr_armed);
-
-  __ Bind(&ok);
-  __ Dispatch();
-
-  __ Bind(&osr_armed);
-  {
-    Callable callable = CodeFactory::InterpreterOnStackReplacement(isolate_);
-    Node* target = __ HeapConstant(callable.code());
-    Node* context = __ GetContext();
-    __ CallStub(callable.descriptor(), target, context);
-    __ Dispatch();
-  }
-}
-
 // Throw
 //
 // Throws the exception in the accumulator.

src/runtime/runtime-compiler.cc

@@ -11,6 +11,7 @@
 #include "src/deoptimizer.h"
 #include "src/frames-inl.h"
 #include "src/full-codegen/full-codegen.h"
+#include "src/interpreter/bytecode-array-iterator.h"
 #include "src/isolate-inl.h"
 #include "src/messages.h"
 #include "src/v8threads.h"
@@ -292,7 +293,20 @@ BailoutId DetermineEntryAndDisarmOSRForInterpreter(JavaScriptFrame* frame) {
   // Reset the OSR loop nesting depth to disarm back edges.
   bytecode->set_osr_loop_nesting_level(0);
 
-  return BailoutId(iframe->GetBytecodeOffset());
+  // Translate the offset of the jump instruction to the jump target offset of
+  // that instruction so that the derived BailoutId points to the loop header.
+  // TODO(mstarzinger): This can be merged with {BytecodeBranchAnalysis} which
+  // already performs a pre-pass over the bytecode stream anyways.
+  int jump_offset = iframe->GetBytecodeOffset();
+  interpreter::BytecodeArrayIterator iterator(bytecode);
+  while (iterator.current_offset() + iterator.current_prefix_offset() <
+         jump_offset) {
+    iterator.Advance();
+  }
+  DCHECK(interpreter::Bytecodes::IsJump(iterator.current_bytecode()));
+  int jump_target_offset = iterator.GetJumpTargetOffset();
+
+  return BailoutId(jump_target_offset);
 }
 
 }  // namespace

test/cctest/interpreter/bytecode_expectations/BreakableBlocks.golden

@@ -49,7 +49,7 @@ snippet: "
 "
 frame size: 5
 parameter count: 1
-bytecode array length: 67
+bytecode array length: 69
 bytecodes: [
   /*   30 E> */ B(StackCheck),
   /*   44 S> */ B(LdaZero),
@@ -58,13 +58,13 @@ bytecodes: [
                 B(Star), R(1),
   /*   76 S> */ B(LdaSmi), U8(10),
   /*   76 E> */ B(TestLessThan), R(1), U8(1),
-                B(JumpIfFalse), U8(52),
+                B(JumpIfFalse), U8(54),
   /*   58 E> */ B(StackCheck),
   /*  106 S> */ B(LdaZero),
                 B(Star), R(2),
   /*  111 S> */ B(LdaSmi), U8(3),
   /*  111 E> */ B(TestLessThan), R(2), U8(3),
-                B(JumpIfFalse), U8(33),
+                B(JumpIfFalse), U8(34),
   /*   93 E> */ B(StackCheck),
   /*  129 S> */ B(Ldar), R(0),
                 B(Inc), U8(5),
@@ -75,15 +75,15 @@ bytecodes: [
                 B(LdaSmi), U8(12),
   /*  152 E> */ B(TestEqual), R(4), U8(7),
                 B(JumpIfFalse), U8(4),
-  /*  161 S> */ B(Jump), U8(18),
+  /*  161 S> */ B(Jump), U8(20),
   /*  118 S> */ B(Ldar), R(2),
                 B(Inc), U8(4),
                 B(Star), R(2),
-                B(Jump), U8(-36),
+                B(JumpLoop), U8(-36), U8(1),
   /*   84 S> */ B(Ldar), R(1),
                 B(Inc), U8(2),
                 B(Star), R(1),
-                B(Jump), U8(-55),
+                B(JumpLoop), U8(-56), U8(0),
   /*  188 S> */ B(Ldar), R(0),
   /*  200 S> */ B(Return),
 ]

test/cctest/interpreter/bytecode_expectations/ForIn.golden

@@ -64,19 +64,19 @@ snippet: "
 "
 frame size: 8
 parameter count: 1
-bytecode array length: 44
+bytecode array length: 45
 bytecodes: [
   /*   30 E> */ B(StackCheck),
   /*   42 S> */ B(LdaConstant), U8(0),
                 B(Star), R(0),
-  /*   68 S> */ B(JumpIfUndefined), U8(37),
-                B(JumpIfNull), U8(35),
+  /*   68 S> */ B(JumpIfUndefined), U8(38),
+                B(JumpIfNull), U8(36),
                 B(ToObject), R(3),
                 B(ForInPrepare), R(3), R(4),
                 B(LdaZero),
                 B(Star), R(7),
   /*   63 S> */ B(ForInContinue), R(7), R(6),
-                B(JumpIfFalse), U8(22),
+                B(JumpIfFalse), U8(23),
                 B(ForInNext), R(3), R(7), R(4), U8(1),
                 B(JumpIfUndefined), U8(9),
                 B(Star), R(1),
@@ -86,7 +86,7 @@ bytecodes: [
   /*   85 S> */ B(Return),
                 B(ForInStep), R(7),
                 B(Star), R(7),
-                B(Jump), U8(-23),
+                B(JumpLoop), U8(-23), U8(0),
                 B(LdaUndefined),
   /*   85 S> */ B(Return),
 ]
@@ -103,20 +103,20 @@ snippet: "
 "
 frame size: 9
 parameter count: 1
-bytecode array length: 55
+bytecode array length: 56
 bytecodes: [
   /*   30 E> */ B(StackCheck),
   /*   42 S> */ B(LdaZero),
                 B(Star), R(0),
   /*   59 S> */ B(CreateArrayLiteral), U8(0), U8(0), U8(1),
-                B(JumpIfUndefined), U8(45),
-                B(JumpIfNull), U8(43),
+                B(JumpIfUndefined), U8(46),
+                B(JumpIfNull), U8(44),
                 B(ToObject), R(3),
                 B(ForInPrepare), R(3), R(4),
                 B(LdaZero),
                 B(Star), R(7),
   /*   54 S> */ B(ForInContinue), R(7), R(6),
-                B(JumpIfFalse), U8(30),
+                B(JumpIfFalse), U8(31),
                 B(ForInNext), R(3), R(7), R(4), U8(2),
                 B(JumpIfUndefined), U8(17),
                 B(Star), R(1),
@@ -128,7 +128,7 @@ bytecodes: [
                 B(Star), R(0),
   /*   72 E> */ B(ForInStep), R(7),
                 B(Star), R(7),
-                B(Jump), U8(-31),
+                B(JumpLoop), U8(-31), U8(0),
                 B(LdaUndefined),
   /*   80 S> */ B(Return),
 ]
@@ -148,20 +148,20 @@ snippet: "
 "
 frame size: 8
 parameter count: 1
-bytecode array length: 82
+bytecode array length: 83
 bytecodes: [
   /*   30 E> */ B(StackCheck),
   /*   42 S> */ B(CreateObjectLiteral), U8(0), U8(0), U8(1), R(1),
                 B(Mov), R(1), R(0),
   /*   77 S> */ B(CreateArrayLiteral), U8(1), U8(1), U8(1),
-                B(JumpIfUndefined), U8(67),
-                B(JumpIfNull), U8(65),
+                B(JumpIfUndefined), U8(68),
+                B(JumpIfNull), U8(66),
                 B(ToObject), R(1),
                 B(ForInPrepare), R(1), R(2),
                 B(LdaZero),
                 B(Star), R(5),
   /*   68 S> */ B(ForInContinue), R(5), R(4),
-                B(JumpIfFalse), U8(52),
+                B(JumpIfFalse), U8(53),
                 B(ForInNext), R(1), R(5), R(2), U8(11),
                 B(JumpIfUndefined), U8(39),
                 B(Star), R(6),
@@ -178,10 +178,10 @@ bytecodes: [
                 B(LdaSmi), U8(20),
   /*  136 E> */ B(TestEqual), R(7), U8(8),
                 B(JumpIfFalse), U8(4),
-  /*  143 S> */ B(Jump), U8(8),
+  /*  143 S> */ B(Jump), U8(9),
                 B(ForInStep), R(5),
                 B(Star), R(5),
-                B(Jump), U8(-53),
+                B(JumpLoop), U8(-53), U8(0),
                 B(LdaUndefined),
   /*  152 S> */ B(Return),
 ]
@@ -200,20 +200,20 @@ snippet: "
 "
 frame size: 9
 parameter count: 1
-bytecode array length: 61
+bytecode array length: 62
 bytecodes: [
   /*   30 E> */ B(StackCheck),
   /*   42 S> */ B(CreateArrayLiteral), U8(0), U8(0), U8(1),
                 B(Star), R(0),
   /*   72 S> */ B(CreateArrayLiteral), U8(1), U8(1), U8(1),
-                B(JumpIfUndefined), U8(48),
-                B(JumpIfNull), U8(46),
+                B(JumpIfUndefined), U8(49),
+                B(JumpIfNull), U8(47),
                 B(ToObject), R(1),
                 B(ForInPrepare), R(1), R(2),
                 B(LdaZero),
                 B(Star), R(5),
   /*   65 S> */ B(ForInContinue), R(5), R(4),
-                B(JumpIfFalse), U8(33),
+                B(JumpIfFalse), U8(34),
                 B(ForInNext), R(1), R(5), R(2), U8(7),
                 B(JumpIfUndefined), U8(20),
                 B(Star), R(6),
@@ -227,7 +227,7 @@ bytecodes: [
   /*   98 S> */ B(Return),
                 B(ForInStep), R(5),
                 B(Star), R(5),
-                B(Jump), U8(-34),
+                B(JumpLoop), U8(-34), U8(0),
                 B(LdaUndefined),
   /*   98 S> */ B(Return),
 ]

test/cctest/interpreter/bytecode_expectations/ForOf.golden

@@ -12,7 +12,7 @@ snippet: "
 "
 frame size: 15
 parameter count: 1
-bytecode array length: 278
+bytecode array length: 279
 bytecodes: [
   /*   30 E> */ B(StackCheck),
                 B(LdaZero),
@@ -33,7 +33,7 @@ bytecodes: [
                 B(JumpIfFalse), U8(7),
                 B(CallRuntime), U16(Runtime::kThrowIteratorResultNotAnObject), R(3), U8(1),
                 B(LdaNamedProperty), R(3), U8(3), U8(9),
-                B(JumpIfToBooleanTrue), U8(23),
+                B(JumpIfToBooleanTrue), U8(24),
                 B(LdrNamedProperty), R(3), U8(4), U8(11), R(5),
                 B(LdaSmi), U8(2),
                 B(Star), R(4),
@@ -42,7 +42,7 @@ bytecodes: [
                 B(Mov), R(0), R(1),
                 B(LdaZero),
                 B(Star), R(4),
-                B(Jump), U8(-49),
+                B(JumpLoop), U8(-49), U8(0),
                 B(Jump), U8(37),
                 B(Star), R(13),
                 B(Ldar), R(closure),
@@ -138,9 +138,9 @@ constant pool: [
   FIXED_ARRAY_TYPE,
 ]
 handlers: [
-  [7, 117, 123],
-  [10, 80, 82],
-  [200, 210, 212],
+  [7, 118, 124],
+  [10, 81, 83],
+  [201, 211, 213],
 ]
 
 ---
@@ -296,7 +296,7 @@ snippet: "
 "
 frame size: 15
 parameter count: 1
-bytecode array length: 296
+bytecode array length: 297
 bytecodes: [
   /*   30 E> */ B(StackCheck),
                 B(LdaZero),
@@ -317,7 +317,7 @@ bytecodes: [
                 B(JumpIfFalse), U8(7),
                 B(CallRuntime), U16(Runtime::kThrowIteratorResultNotAnObject), R(3), U8(1),
                 B(LdaNamedProperty), R(3), U8(3), U8(9),
-                B(JumpIfToBooleanTrue), U8(41),
+                B(JumpIfToBooleanTrue), U8(42),
                 B(LdrNamedProperty), R(3), U8(4), U8(11), R(5),
                 B(LdaSmi), U8(2),
                 B(Star), R(4),
@@ -331,10 +331,10 @@ bytecodes: [
   /*   91 S> */ B(LdaSmi), U8(20),
   /*   97 E> */ B(TestEqual), R(1), U8(14),
                 B(JumpIfFalse), U8(4),
-  /*  104 S> */ B(Jump), U8(7),
+  /*  104 S> */ B(Jump), U8(8),
                 B(LdaZero),
                 B(Star), R(4),
-                B(Jump), U8(-67),
+                B(JumpLoop), U8(-67), U8(0),
                 B(Jump), U8(37),
                 B(Star), R(13),
                 B(Ldar), R(closure),
@@ -430,9 +430,9 @@ constant pool: [
   FIXED_ARRAY_TYPE,
 ]
 handlers: [
-  [7, 135, 141],
-  [10, 98, 100],
-  [218, 228, 230],
+  [7, 136, 142],
+  [10, 99, 101],
+  [219, 229, 231],
 ]
 
 ---

test/cctest/interpreter/bytecode_expectations/Generators.golden

@@ -267,7 +267,7 @@ snippet: "
 "
 frame size: 18
 parameter count: 1
-bytecode array length: 805
+bytecode array length: 807
 bytecodes: [
                 B(Ldar), R(new_target),
                 B(JumpIfUndefined), U8(28),
@@ -417,14 +417,14 @@ bytecodes: [
                 B(Star), R(9),
                 B(LdaZero),
                 B(Star), R(8),
-                B(Jump), U8(74),
+                B(Jump), U8(76),
                 B(Ldar), R(13),
   /*   36 E> */ B(Throw),
                 B(Ldar), R(13),
                 B(PopContext), R(2),
                 B(LdaZero),
                 B(StaContextSlot), R(1), U8(9), U8(0),
-                B(Wide), B(Jump), U16(-234),
+                B(Wide), B(JumpLoop), U16(-234), U16(0),
                 B(Jump), U8(44),
                 B(Star), R(12),
                 B(Ldar), R(closure),
@@ -585,7 +585,7 @@ constant pool: [
   FIXED_ARRAY_TYPE,
   ONE_BYTE_INTERNALIZED_STRING_TYPE ["x"],
   Smi [146],
-  Smi [167],
+  Smi [169],
   ONE_BYTE_INTERNALIZED_STRING_TYPE [".catch"],
   FIXED_ARRAY_TYPE,
   ONE_BYTE_INTERNALIZED_STRING_TYPE ["return"],
@@ -595,12 +595,12 @@ constant pool: [
   Smi [129],
   Smi [166],
   Smi [155],
-  Smi [601],
+  Smi [603],
 ]
 handlers: [
-  [48, 718, 724],
-  [153, 458, 464],
-  [156, 414, 416],
-  [572, 586, 588],
+  [48, 720, 726],
+  [153, 460, 466],
+  [156, 416, 418],
+  [574, 588, 590],
 ]
 

test/cctest/interpreter/bytecode_expectations/JumpsRequiringConstantWideOperands.golden

@@ -328,7 +328,7 @@ snippet: "
 "
 frame size: 2
 parameter count: 1
-bytecode array length: 1411
+bytecode array length: 1412
 bytecodes: [
   /*   30 E> */ B(StackCheck),
   /*   42 S> */ B(LdaConstant), U8(0),
@@ -959,7 +959,7 @@ bytecodes: [
                 B(Star), R(1),
   /* 4108 S> */ B(LdaSmi), U8(3),
   /* 4108 E> */ B(TestLessThan), R(1), U8(1),
-                B(Wide), B(JumpIfFalse), U16(38),
+                B(Wide), B(JumpIfFalse), U16(39),
   /* 4090 E> */ B(StackCheck),
   /* 4122 S> */ B(LdaSmi), U8(1),
   /* 4128 E> */ B(TestEqual), R(1), U8(3),
@@ -968,11 +968,11 @@ bytecodes: [
   /* 4146 S> */ B(LdaSmi), U8(2),
   /* 4152 E> */ B(TestEqual), R(1), U8(4),
                 B(Wide), B(JumpIfFalse), U16(7),
-  /* 4158 S> */ B(Wide), B(Jump), U16(11),
+  /* 4158 S> */ B(Wide), B(Jump), U16(12),
   /* 4114 S> */ B(Ldar), R(1),
                 B(Inc), U8(2),
                 B(Star), R(1),
-                B(Jump), U8(-42),
+                B(JumpLoop), U8(-42), U8(0),
   /* 4167 S> */ B(LdaSmi), U8(3),
   /* 4177 S> */ B(Return),
 ]

test/cctest/interpreter/bytecode_expectations/RemoveRedundantLdar.golden

@@ -17,7 +17,7 @@ snippet: "
 "
 frame size: 1
 parameter count: 1
-bytecode array length: 27
+bytecode array length: 28
 bytecodes: [
   /*   30 E> */ B(StackCheck),
   /*   45 S> */ B(LdaSmi), U8(1),
@@ -29,8 +29,8 @@ bytecodes: [
   /*   86 S> */ B(LdaSmi), U8(10),
   /*   95 E> */ B(TestGreaterThan), R(0), U8(2),
                 B(JumpIfFalse), U8(4),
-  /*  101 S> */ B(Jump), U8(4),
-                B(Jump), U8(-17),
+  /*  101 S> */ B(Jump), U8(5),
+                B(JumpLoop), U8(-17), U8(0),
   /*  110 S> */ B(Ldar), R(0),
   /*  123 S> */ B(Return),
 ]

test/cctest/interpreter/bytecode_expectations/UnaryOperators.golden

@@ -16,18 +16,18 @@ snippet: "
 "
 frame size: 1
 parameter count: 1
-bytecode array length: 23
+bytecode array length: 24
 bytecodes: [
   /*   30 E> */ B(StackCheck),
   /*   42 S> */ B(LdaZero),
                 B(Star), R(0),
   /*   54 S> */ B(LdaSmi), U8(10),
   /*   54 E> */ B(TestEqual), R(0), U8(1),
-                B(JumpIfTrue), U8(11),
+                B(JumpIfTrue), U8(12),
   /*   45 E> */ B(StackCheck),
   /*   65 S> */ B(AddSmi), U8(10), R(0), U8(2),
                 B(Star), R(0),
-                B(Jump), U8(-14),
+                B(JumpLoop), U8(-14), U8(0),
   /*   79 S> */ B(Ldar), R(0),
   /*   89 S> */ B(Return),
 ]
@@ -46,7 +46,7 @@ snippet: "
 "
 frame size: 1
 parameter count: 1
-bytecode array length: 19
+bytecode array length: 22
 bytecodes: [
   /*   30 E> */ B(StackCheck),
   /*   42 S> */ B(LdaFalse),
@@ -57,7 +57,8 @@ bytecodes: [
                 B(Star), R(0),
   /*   74 S> */ B(LdaFalse),
   /*   74 E> */ B(TestEqual), R(0), U8(1),
-                B(JumpIfTrue), U8(-10),
+                B(JumpIfFalse), U8(5),
+                B(JumpLoop), U8(-12), U8(0),
   /*   85 S> */ B(Ldar), R(0),
   /*   95 S> */ B(Return),
 ]

test/cctest/interpreter/bytecode_expectations/WideRegisters.golden

@@ -892,7 +892,7 @@ snippet: "
 "
 frame size: 158
 parameter count: 1
-bytecode array length: 55
+bytecode array length: 56
 bytecodes: [
   /*   30 E> */ B(StackCheck),
   /* 1503 S> */ B(LdaZero),
@@ -903,7 +903,7 @@ bytecodes: [
                 B(Wide), B(Star), R16(128),
   /* 1538 S> */ B(LdaSmi), U8(64),
   /* 1538 E> */ B(Wide), B(TestLessThan), R16(128), U16(1),
-                B(JumpIfFalse), U8(30),
+                B(JumpIfFalse), U8(31),
   /* 1518 E> */ B(StackCheck),
   /* 1555 S> */ B(Wide), B(Ldar), R16(128),
   /* 1561 E> */ B(Add), R(1), U8(3),
@@ -912,7 +912,7 @@ bytecodes: [
   /* 1548 S> */ B(Wide), B(Ldar), R16(128),
                 B(Inc), U8(2),
                 B(Wide), B(Star), R16(128),
-                B(Jump), U8(-36),
+                B(JumpLoop), U8(-36), U8(0),
   /* 1567 S> */ B(Wide), B(Ldar), R16(128),
   /* 1580 S> */ B(Return),
 ]
@@ -1086,7 +1086,7 @@ snippet: "
 "
 frame size: 163
 parameter count: 1
-bytecode array length: 84
+bytecode array length: 85
 bytecodes: [
   /*   30 E> */ B(StackCheck),
   /* 1503 S> */ B(Wide), B(LdaSmi), U16(1234),
@@ -1094,14 +1094,14 @@ bytecodes: [
   /* 1518 S> */ B(LdaZero),
                 B(Star), R(1),
   /* 1534 S> */ B(Ldar), R(0),
-                B(JumpIfUndefined), U8(69),
-                B(JumpIfNull), U8(67),
+                B(JumpIfUndefined), U8(70),
+                B(JumpIfNull), U8(68),
                 B(Wide), B(ToObject), R16(157),
                 B(Wide), B(ForInPrepare), R16(157), R16(158),
                 B(LdaZero),
                 B(Wide), B(Star), R16(161),
   /* 1526 S> */ B(Wide), B(ForInContinue), R16(161), R16(160),
-                B(JumpIfFalse), U8(44),
+                B(JumpIfFalse), U8(45),
                 B(Wide), B(ForInNext), R16(157), R16(161), R16(158), U16(2),
                 B(JumpIfUndefined), U8(22),
                 B(Wide), B(Star), R16(128),
@@ -1112,7 +1112,7 @@ bytecodes: [
                 B(Star), R(1),
   /* 1544 E> */ B(Wide), B(ForInStep), R16(161),
                 B(Wide), B(Star), R16(161),
-                B(Jump), U8(-48),
+                B(JumpLoop), U8(-48), U8(0),
   /* 1553 S> */ B(Ldar), R(1),
   /* 1564 S> */ B(Return),
 ]

test/cctest/interpreter/test-bytecode-generator.cc

@@ -72,7 +72,6 @@ class InitializedIgnitionHandleScope : public InitializedHandleScope {
  public:
   InitializedIgnitionHandleScope() {
     i::FLAG_ignition = true;
-    i::FLAG_ignition_osr = false;  // TODO(4764): Disabled for now.
     i::FLAG_always_opt = false;
     i::FLAG_allow_natives_syntax = true;
     CcTest::i_isolate()->interpreter()->Initialize();

test/cctest/interpreter/test-interpreter.cc

@@ -1408,7 +1408,7 @@ TEST(InterpreterJumps) {
       .Jump(&label[2]);
   SetRegister(builder, reg, 2048, scratch).Bind(&label[1]);
   IncrementRegister(builder, reg, 2, scratch, vector->GetIndex(slot1))
-      .Jump(&label[0]);
+      .JumpLoop(&label[0], 0);
   SetRegister(builder, reg, 4096, scratch).Bind(&label[2]);
   IncrementRegister(builder, reg, 4, scratch, vector->GetIndex(slot2))
       .LoadAccumulatorWithRegister(reg)

test/unittests/interpreter/bytecode-array-writer-unittest.cc

@@ -44,8 +44,8 @@ class BytecodeArrayWriterUnittest : public TestWithIsolateAndZone {
              const BytecodeSourceInfo& info = BytecodeSourceInfo());
 
   void WriteJump(Bytecode bytecode, BytecodeLabel* label,
-
                  const BytecodeSourceInfo& info = BytecodeSourceInfo());
+  void WriteJumpLoop(Bytecode bytecode, BytecodeLabel* label, int depth);
 
   BytecodeArrayWriter* writer() { return &bytecode_array_writer_; }
   ZoneVector<unsigned char>* bytecodes() { return writer()->bytecodes(); }
@@ -111,6 +111,13 @@ void BytecodeArrayWriterUnittest::WriteJump(Bytecode bytecode,
   writer()->WriteJump(&node, label);
 }
 
+void BytecodeArrayWriterUnittest::WriteJumpLoop(Bytecode bytecode,
+                                                BytecodeLabel* label,
+                                                int depth) {
+  BytecodeNode node(bytecode, 0, depth);
+  writer()->WriteJump(&node, label);
+}
+
 TEST_F(BytecodeArrayWriterUnittest, SimpleExample) {
   CHECK_EQ(bytecodes()->size(), 0);
 
@@ -161,14 +168,14 @@ TEST_F(BytecodeArrayWriterUnittest, ComplexExample) {
       /*  0 30 E> */ B(StackCheck),
       /*  1 42 S> */ B(LdaConstant), U8(0),
       /*  3 42 E> */ B(Star), R8(1),
-      /*  5 68 S> */ B(JumpIfUndefined), U8(38),
-      /*  7       */ B(JumpIfNull), U8(36),
+      /*  5 68 S> */ B(JumpIfUndefined), U8(39),
+      /*  7       */ B(JumpIfNull), U8(37),
       /*  9       */ B(ToObject), R8(3),
       /* 11       */ B(ForInPrepare), R8(3), R8(4),
       /* 14       */ B(LdaZero),
       /* 15       */ B(Star), R8(7),
       /* 17 63 S> */ B(ForInContinue), R8(7), R8(6),
-      /* 20       */ B(JumpIfFalse), U8(23),
+      /* 20       */ B(JumpIfFalse), U8(24),
       /* 22       */ B(ForInNext), R8(3), R8(7), R8(4), U8(1),
       /* 27       */ B(JumpIfUndefined), U8(10),
       /* 29       */ B(Star), R8(0),
@@ -178,15 +185,15 @@ TEST_F(BytecodeArrayWriterUnittest, ComplexExample) {
       /* 36 85 S> */ B(Return),
       /* 37       */ B(ForInStep), R8(7),
       /* 39       */ B(Star), R8(7),
-      /* 41       */ B(Jump), U8(-24),
-      /* 43       */ B(LdaUndefined),
-      /* 44 85 S> */ B(Return),
+      /* 41       */ B(JumpLoop), U8(-24), U8(0),
+      /* 44       */ B(LdaUndefined),
+      /* 45 85 S> */ B(Return),
       // clang-format on
   };
 
   static const PositionTableEntry expected_positions[] = {
       {0, 30, false}, {1, 42, true},   {3, 42, false}, {5, 68, true},
-      {17, 63, true}, {31, 54, false}, {36, 85, true}, {44, 85, true}};
+      {17, 63, true}, {31, 54, false}, {36, 85, true}, {45, 85, true}};
 
   BytecodeLabel back_jump, jump_for_in, jump_end_1, jump_end_2, jump_end_3;
 
@@ -220,7 +227,7 @@ TEST_F(BytecodeArrayWriterUnittest, ComplexExample) {
   writer()->BindLabel(&jump_for_in);
   Write(Bytecode::kForInStep, R(7));
   Write(Bytecode::kStar, R(7));
-  WriteJump(Bytecode::kJump, &back_jump);
+  WriteJumpLoop(Bytecode::kJumpLoop, &back_jump, 0);
   writer()->BindLabel(&jump_end_1);
   writer()->BindLabel(&jump_end_2);
   writer()->BindLabel(&jump_end_3);