[interpreter] Ensure optimizations preserve source positions.

src/interpreter/bytecodes.cc

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/interpreter/bytecodes.h"
 
 #include <iomanip>
 
 #include "src/frames.h"
 #include "src/interpreter/bytecode-traits.h"
@@ skipping 89 matching lines @@
   return "";
 }
 
 // static
 Bytecode Bytecodes::FromByte(uint8_t value) {
   Bytecode bytecode = static_cast<Bytecode>(value);
   DCHECK(bytecode <= Bytecode::kLast);
   return bytecode;
 }
 
-
 // static
 Bytecode Bytecodes::GetDebugBreak(Bytecode bytecode) {
   DCHECK(!IsDebugBreak(bytecode));
   if (bytecode == Bytecode::kWide) {
     return Bytecode::kDebugBreakWide;
   }
   if (bytecode == Bytecode::kExtraWide) {
     return Bytecode::kDebugBreakExtraWide;
   }
   int bytecode_size = Size(bytecode, OperandScale::kSingle);
@@ skipping 12 matching lines @@
   int size = 1;
   for (int i = 0; i < NumberOfOperands(bytecode); i++) {
     OperandSize operand_size = GetOperandSize(bytecode, i, operand_scale);
     int delta = static_cast<int>(operand_size);
     DCHECK(base::bits::IsPowerOfTwo32(static_cast<uint32_t>(delta)));
     size += delta;
   }
   return size;
 }
 
-
 // static
 size_t Bytecodes::ReturnCount(Bytecode bytecode) {
   return bytecode == Bytecode::kReturn ? 1 : 0;
 }
 
 // static
 int Bytecodes::NumberOfOperands(Bytecode bytecode) {
   DCHECK(bytecode <= Bytecode::kLast);
   switch (bytecode) {
 #define CASE(Name, ...)   \
   case Bytecode::k##Name: \
     return BytecodeTraits<__VA_ARGS__>::kOperandCount;
     BYTECODE_LIST(CASE)
 #undef CASE
   }
   UNREACHABLE();
   return 0;
 }
 
-
 // static
 int Bytecodes::NumberOfRegisterOperands(Bytecode bytecode) {
   DCHECK(bytecode <= Bytecode::kLast);
   switch (bytecode) {
 #define CASE(Name, ...)                              \
   case Bytecode::k##Name:                            \
     typedef BytecodeTraits<__VA_ARGS__> Name##Trait; \
     return Name##Trait::kRegisterOperandCount;
     BYTECODE_LIST(CASE)
 #undef CASE
@@ skipping 96 matching lines @@
     case Bytecode::kLdaFalse:
     case Bytecode::kLdaConstant:
     case Bytecode::kLdar:
       return true;
     default:
       return false;
   }
 }
 
 // static
+bool Bytecodes::IsJumpWithoutEffects(Bytecode bytecode) {
+  return IsJump(bytecode) && !IsJumpIfToBoolean(bytecode);
+}
+
+// static
+bool Bytecodes::IsRegisterLoadWithoutEffects(Bytecode bytecode) {
+  switch (bytecode) {
+    case Bytecode::kMov:
+    case Bytecode::kPopContext:
+    case Bytecode::kPushContext:
+    case Bytecode::kStar:
+    case Bytecode::kLdrUndefined:
+      return true;
+    default:
+      return false;
+  }
+}
+
+// static
+bool Bytecodes::IsWithoutExternalSideEffects(Bytecode bytecode) {
+  // These bytecodes only manipulate interpreter frame state and will
+  // never throw.
+  return (IsAccumulatorLoadWithoutEffects(bytecode) ||
+          IsRegisterLoadWithoutEffects(bytecode) ||
+          bytecode == Bytecode::kNop || IsJumpWithoutEffects(bytecode));
+}
+
+// static
 OperandType Bytecodes::GetOperandType(Bytecode bytecode, int i) {
   DCHECK_LE(bytecode, Bytecode::kLast);
   DCHECK_LT(i, NumberOfOperands(bytecode));
   DCHECK_GE(i, 0);
   return GetOperandTypes(bytecode)[i];
 }
 
 // static
 const OperandType* Bytecodes::GetOperandTypes(Bytecode bytecode) {
   DCHECK(bytecode <= Bytecode::kLast);
@@ skipping 191 matching lines @@
     case Bytecode::kDebugBreakExtraWide:
     case Bytecode::kWide:
     case Bytecode::kDebugBreakWide:
       return true;
     default:
       return false;
   }
 }
 
 // static
-bool Bytecodes::IsWithoutExternalSideEffects(Bytecode bytecode) {
-  // These bytecodes only manipulate interpreter frame state and will
-  // never throw.
-  return (IsAccumulatorLoadWithoutEffects(bytecode) || IsLdarOrStar(bytecode) ||
-          bytecode == Bytecode::kMov || bytecode == Bytecode::kNop ||
-          IsJump(bytecode));
-}
-
-// static
 bool Bytecodes::IsJumpOrReturn(Bytecode bytecode) {
   return bytecode == Bytecode::kReturn || IsJump(bytecode);
 }
 
 // static
 bool Bytecodes::IsMaybeRegisterOperandType(OperandType operand_type) {
   return operand_type == OperandType::kMaybeReg;
 }
 
 // static
@@ skipping 462 matching lines @@
   } else {
     std::ostringstream s;
     s << "r" << index();
     return s.str();
   }
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8