[interpreter] Add support for scalable operands.

src/interpreter/bytecodes.cc

Index: src/interpreter/bytecodes.cc
diff --git a/src/interpreter/bytecodes.cc b/src/interpreter/bytecodes.cc
index 5f7a9085aec33bdba04bcd4764a8cfac73a6e667..ae5b349a241c7221ea5d1073ad52a005a7bce472 100644
--- a/src/interpreter/bytecodes.cc
+++ b/src/interpreter/bytecodes.cc
@@ -29,7 +29,7 @@ const char* Bytecodes::ToString(Bytecode bytecode) {
 // static
 const char* Bytecodes::OperandTypeToString(OperandType operand_type) {
   switch (operand_type) {
-#define CASE(Name, _)        \
+#define CASE(Name, _, __)    \
   case OperandType::k##Name: \
     return #Name;
     OPERAND_TYPE_LIST(CASE)
@@ -49,6 +49,8 @@ const char* Bytecodes::OperandSizeToString(OperandSize operand_size) {
       return "Byte";
     case OperandSize::kShort:
       return "Short";
+    case OperandSize::kQuad:
+      return "Quad";
   }
   UNREACHABLE();
   return "";
@@ -71,32 +73,28 @@ Bytecode Bytecodes::FromByte(uint8_t value) {
 
 
 // static
-Bytecode Bytecodes::GetDebugBreak(Bytecode bytecode) {
-  switch (Size(bytecode)) {
-#define CASE(Name, ...)                                  \
-  case BytecodeTraits<__VA_ARGS__, OPERAND_TERM>::kSize: \
-    return Bytecode::k##Name;
-    DEBUG_BREAK_BYTECODE_LIST(CASE)
-#undef CASE
-    default:
-      break;
+Bytecode Bytecodes::GetDebugBreak(Bytecode bytecode, int operand_scale) {
+  int bytecode_size = Size(bytecode, operand_scale);
+#define RETURN_IF_DEBUG_BREAK_SIZE_MATCHES(Name, ...)            \
+  if (bytecode_size == Size(Bytecode::k##Name, operand_scale)) { \
+    return Bytecode::k##Name;                                    \
   }
+  DEBUG_BREAK_BYTECODE_LIST(RETURN_IF_DEBUG_BREAK_SIZE_MATCHES)
+#undef RETURN_IF_DEBUG_BREAK_SIZE_MATCHES
   UNREACHABLE();
   return static_cast<Bytecode>(-1);
 }
 
 // static
-int Bytecodes::Size(Bytecode bytecode) {
-  DCHECK(bytecode <= Bytecode::kLast);
-  switch (bytecode) {
-#define CASE(Name, ...)   \
-  case Bytecode::k##Name: \
-    return BytecodeTraits<__VA_ARGS__, OPERAND_TERM>::kSize;
-    BYTECODE_LIST(CASE)
-#undef CASE
+int Bytecodes::Size(Bytecode bytecode, int operand_scale) {
+  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;
   }
-  UNREACHABLE();
-  return 0;
+  return size;
 }
 
 
@@ -131,6 +129,18 @@ int Bytecodes::NumberOfRegisterOperands(Bytecode bytecode) {
 }
 
 // static
+int Bytecodes::GetPrefixBytecodeScale(Bytecode bytecode) {
+  switch (bytecode) {
+    case Bytecode::kExtraWide:
+      return 4;
+    case Bytecode::kWide:
+      return 2;
+    default:
+      return 1;
+  }
+}
+
+// static
 OperandType Bytecodes::GetOperandType(Bytecode bytecode, int i) {
   DCHECK(bytecode <= Bytecode::kLast);
   switch (bytecode) {
@@ -144,23 +154,47 @@ OperandType Bytecodes::GetOperandType(Bytecode bytecode, int i) {
   return OperandType::kNone;
 }
 
+// TODO(oth): TEMPORARY
+namespace {
 
-// static
-OperandSize Bytecodes::GetOperandSize(Bytecode bytecode, int i) {
-  DCHECK(bytecode <= Bytecode::kLast);
-  switch (bytecode) {
-#define CASE(Name, ...)   \
-  case Bytecode::k##Name: \
-    return BytecodeTraits<__VA_ARGS__, OPERAND_TERM>::GetOperandSize(i);
-    BYTECODE_LIST(CASE)
+template <OperandTypeTrait O>
+struct OperandScaler {
+  static int Multiply(int size, int scale) { return 0; }
+};
+
+template <>
+struct OperandScaler<OperandTypeTrait::kFixed> {
+  static int Multiply(int size, int scale) { return size; }
+};
+
+template <>
+struct OperandScaler<OperandTypeTrait::kScalable> {
+  static int Multiply(int size, int scale) { return size * scale; }
+};
+
+}  // namespace
+
+// TODO(oth): TEMPORARY
+static int ScaledOperandSize(OperandType operand_type, int scale) {
+  switch (operand_type) {
+#define CASE(Name, Size, Trait) \
+  case OperandType::k##Name:    \
+    return OperandScaler<Trait>::Multiply(static_cast<int>(Size), scale);
+    OPERAND_TYPE_LIST(CASE)
 #undef CASE
   }
   UNREACHABLE();
-  return OperandSize::kNone;
+  return 0;
 }
 
 
 // static
+OperandSize Bytecodes::GetOperandSize(Bytecode bytecode, int i, int scale) {
+  OperandType op_type = GetOperandType(bytecode, i);
+  return static_cast<OperandSize>(ScaledOperandSize(op_type, scale));
+}
+
+// static
 int Bytecodes::GetRegisterOperandBitmap(Bytecode bytecode) {
   DCHECK(bytecode <= Bytecode::kLast);
   switch (bytecode) {
@@ -176,31 +210,18 @@ int Bytecodes::GetRegisterOperandBitmap(Bytecode bytecode) {
 }
 
 // static
-int Bytecodes::GetOperandOffset(Bytecode bytecode, int i) {
-  DCHECK(bytecode <= Bytecode::kLast);
-  switch (bytecode) {
-#define CASE(Name, ...)   \
-  case Bytecode::k##Name: \
-    return BytecodeTraits<__VA_ARGS__, OPERAND_TERM>::GetOperandOffset(i);
-    BYTECODE_LIST(CASE)
-#undef CASE
+int Bytecodes::GetOperandOffset(Bytecode bytecode, int i, int scale) {
+  int offset = 1;
+  for (int operand_index = 0; operand_index < i; ++operand_index) {
+    OperandSize operand_size = GetOperandSize(bytecode, operand_index, scale);
+    offset += static_cast<int>(operand_size);
   }
-  UNREACHABLE();
-  return 0;
+  return offset;
 }
 
-
 // static
-OperandSize Bytecodes::SizeOfOperand(OperandType operand_type) {
-  switch (operand_type) {
-#define CASE(Name, Size)     \
-  case OperandType::k##Name: \
-    return Size;
-    OPERAND_TYPE_LIST(CASE)
-#undef CASE
-  }
-  UNREACHABLE();
-  return OperandSize::kNone;
+OperandSize Bytecodes::SizeOfOperand(OperandType operand_type, int scale) {
+  return static_cast<OperandSize>(ScaledOperandSize(operand_type, scale));
 }
 
 
@@ -227,24 +248,10 @@ bool Bytecodes::IsConditionalJumpConstant(Bytecode bytecode) {
          bytecode == Bytecode::kJumpIfUndefinedConstant;
 }
 
-
-// static
-bool Bytecodes::IsConditionalJumpConstantWide(Bytecode bytecode) {
-  return bytecode == Bytecode::kJumpIfTrueConstantWide ||
-         bytecode == Bytecode::kJumpIfFalseConstantWide ||
-         bytecode == Bytecode::kJumpIfToBooleanTrueConstantWide ||
-         bytecode == Bytecode::kJumpIfToBooleanFalseConstantWide ||
-         bytecode == Bytecode::kJumpIfNotHoleConstantWide ||
-         bytecode == Bytecode::kJumpIfNullConstantWide ||
-         bytecode == Bytecode::kJumpIfUndefinedConstantWide;
-}
-
-
 // static
 bool Bytecodes::IsConditionalJump(Bytecode bytecode) {
   return IsConditionalJumpImmediate(bytecode) ||
-         IsConditionalJumpConstant(bytecode) ||
-         IsConditionalJumpConstantWide(bytecode);
+         IsConditionalJumpConstant(bytecode);
 }
 
 
@@ -260,34 +267,22 @@ bool Bytecodes::IsJumpConstant(Bytecode bytecode) {
          IsConditionalJumpConstant(bytecode);
 }
 
-
-// static
-bool Bytecodes::IsJumpConstantWide(Bytecode bytecode) {
-  return bytecode == Bytecode::kJumpConstantWide ||
-         IsConditionalJumpConstantWide(bytecode);
-}
-
-
 // static
 bool Bytecodes::IsJump(Bytecode bytecode) {
-  return IsJumpImmediate(bytecode) || IsJumpConstant(bytecode) ||
-         IsJumpConstantWide(bytecode);
+  return IsJumpImmediate(bytecode) || IsJumpConstant(bytecode);
 }
 
 
 // static
 bool Bytecodes::IsCallOrNew(Bytecode bytecode) {
   return bytecode == Bytecode::kCall || bytecode == Bytecode::kTailCall ||
-         bytecode == Bytecode::kNew || bytecode == Bytecode::kCallWide ||
-         bytecode == Bytecode::kTailCallWide || bytecode == Bytecode::kNewWide;
+         bytecode == Bytecode::kNew;
 }
 
 // static
 bool Bytecodes::IsCallRuntime(Bytecode bytecode) {
   return bytecode == Bytecode::kCallRuntime ||
-         bytecode == Bytecode::kCallRuntimeWide ||
-         bytecode == Bytecode::kCallRuntimeForPair ||
-         bytecode == Bytecode::kCallRuntimeForPairWide;
+         bytecode == Bytecode::kCallRuntimeForPair;
 }
 
 // static
@@ -304,42 +299,63 @@ bool Bytecodes::IsDebugBreak(Bytecode bytecode) {
 }
 
 // static
+bool Bytecodes::IsBytecodeWithScalableOperands(Bytecode bytecode) {
+  switch (bytecode) {
+#define CASE(Name, ...)                                            \
+  case Bytecode::k##Name:                                          \
+    typedef BytecodeTraits<__VA_ARGS__, OPERAND_TERM> Name##Trait; \
+    return Name##Trait::IsScalable();
+    BYTECODE_LIST(CASE)
+#undef CASE
+  }
+  UNREACHABLE();
+  return false;
+}
+
+// static
 bool Bytecodes::IsJumpOrReturn(Bytecode bytecode) {
   return bytecode == Bytecode::kReturn || IsJump(bytecode);
 }
 
 // static
+bool Bytecodes::IsFlagOperandType(OperandType operand_type) {
+  return operand_type == OperandType::kFlag8;
+}
+
+// static
 bool Bytecodes::IsIndexOperandType(OperandType operand_type) {
-  return operand_type == OperandType::kIdx8 ||
-         operand_type == OperandType::kIdx16;
+  return operand_type == OperandType::kIdx;
 }
 
 // static
 bool Bytecodes::IsImmediateOperandType(OperandType operand_type) {
-  return operand_type == OperandType::kImm8;
+  return operand_type == OperandType::kImm;
 }
 
 // static
 bool Bytecodes::IsRegisterCountOperandType(OperandType operand_type) {
-  return (operand_type == OperandType::kRegCount8 ||
-          operand_type == OperandType::kRegCount16);
+  return operand_type == OperandType::kRegCount;
 }
 
 // static
 bool Bytecodes::IsMaybeRegisterOperandType(OperandType operand_type) {
-  return (operand_type == OperandType::kMaybeReg8 ||
-          operand_type == OperandType::kMaybeReg16);
+  return operand_type == OperandType::kMaybeReg;
+}
+
+// static
+bool Bytecodes::IsRuntimeIdOperandType(OperandType operand_type) {
+  return operand_type == OperandType::kRuntimeId;
 }
 
 // static
 bool Bytecodes::IsRegisterOperandType(OperandType operand_type) {
   switch (operand_type) {
-#define CASE(Name, _)        \
+#define CASE(Name, _, __)    \
   case OperandType::k##Name: \
     return true;
     REGISTER_OPERAND_TYPE_LIST(CASE)
 #undef CASE
-#define CASE(Name, _)        \
+#define CASE(Name, _, __)    \
   case OperandType::k##Name: \
     break;
     NON_REGISTER_OPERAND_TYPE_LIST(CASE)
@@ -351,12 +367,12 @@ bool Bytecodes::IsRegisterOperandType(OperandType operand_type) {
 // static
 bool Bytecodes::IsRegisterInputOperandType(OperandType operand_type) {
   switch (operand_type) {
-#define CASE(Name, _)        \
+#define CASE(Name, _, __)    \
   case OperandType::k##Name: \
     return true;
     REGISTER_INPUT_OPERAND_TYPE_LIST(CASE)
 #undef CASE
-#define CASE(Name, _)        \
+#define CASE(Name, _, __)    \
   case OperandType::k##Name: \
     break;
     NON_REGISTER_OPERAND_TYPE_LIST(CASE)
@@ -369,12 +385,12 @@ bool Bytecodes::IsRegisterInputOperandType(OperandType operand_type) {
 // static
 bool Bytecodes::IsRegisterOutputOperandType(OperandType operand_type) {
   switch (operand_type) {
-#define CASE(Name, _)        \
+#define CASE(Name, _, __)    \
   case OperandType::k##Name: \
     return true;
     REGISTER_OUTPUT_OPERAND_TYPE_LIST(CASE)
 #undef CASE
-#define CASE(Name, _)        \
+#define CASE(Name, _, __)    \
   case OperandType::k##Name: \
     break;
     NON_REGISTER_OPERAND_TYPE_LIST(CASE)
@@ -386,18 +402,52 @@ bool Bytecodes::IsRegisterOutputOperandType(OperandType operand_type) {
 
 namespace {
 static Register DecodeRegister(const uint8_t* operand_start,
-                               OperandType operand_type) {
-  switch (Bytecodes::SizeOfOperand(operand_type)) {
+                               OperandType operand_type, int operand_scale) {
+  switch (Bytecodes::SizeOfOperand(operand_type, operand_scale)) {
     case OperandSize::kByte:
       return Register::FromOperand(*operand_start);
     case OperandSize::kShort:
       return Register::FromWideOperand(ReadUnalignedUInt16(operand_start));
+    case OperandSize::kQuad:
+      return Register::FromWideOperand(ReadUnalignedUInt32(operand_start));
     case OperandSize::kNone: {
       UNREACHABLE();
     }
   }
   return Register();
 }
+
+static uint32_t DecodeUnsignedOperand(const uint8_t* operand_start,
+                                      OperandType operand_type,
+                                      int operand_scale) {
+  switch (Bytecodes::SizeOfOperand(operand_type, operand_scale)) {
+    case OperandSize::kByte:
+      return *operand_start;
+    case OperandSize::kShort:
+      return ReadUnalignedUInt16(operand_start);
+    case OperandSize::kQuad:
+      return ReadUnalignedUInt32(operand_start);
+    case OperandSize::kNone:
+      UNREACHABLE();
+  }
+  return 0;
+}
+
+static int32_t DecodeSignedOperand(const uint8_t* operand_start,
+                                   OperandType operand_type,
+                                   int operand_scale) {
+  switch (Bytecodes::SizeOfOperand(operand_type, operand_scale)) {
+    case OperandSize::kByte:
+      return static_cast<int8_t>(*operand_start);
+    case OperandSize::kShort:
+      return static_cast<int16_t>(ReadUnalignedUInt16(operand_start));
+    case OperandSize::kQuad:
+      return static_cast<int32_t>(ReadUnalignedUInt32(operand_start));
+    case OperandSize::kNone:
+      UNREACHABLE();
+  }
+  return 0;
+}
 }  // namespace
 
 
@@ -407,18 +457,31 @@ std::ostream& Bytecodes::Decode(std::ostream& os, const uint8_t* bytecode_start,
   Vector<char> buf = Vector<char>::New(50);
 
   Bytecode bytecode = Bytecodes::FromByte(bytecode_start[0]);
-  int bytecode_size = Bytecodes::Size(bytecode);
+  int prefix_offset = 0;
+  int operand_scale = Bytecodes::GetPrefixBytecodeScale(bytecode);
+  if (operand_scale > 1) {
+    prefix_offset += 1;
+    bytecode = Bytecodes::FromByte(bytecode_start[1]);
+  }
 
-  for (int i = 0; i < bytecode_size; i++) {
+  int bytecode_size = Bytecodes::Size(bytecode, operand_scale);
+
+  for (int i = 0; i < prefix_offset + bytecode_size; i++) {
     SNPrintF(buf, "%02x ", bytecode_start[i]);
     os << buf.start();
   }
   const int kBytecodeColumnSize = 6;
-  for (int i = bytecode_size; i < kBytecodeColumnSize; i++) {
+  for (int i = prefix_offset + bytecode_size; i < kBytecodeColumnSize; i++) {
     os << "   ";
   }
 
-  os << bytecode << " ";
+  os << bytecode;
+  if (operand_scale == 2) {
+    os << "." << Bytecodes::ToString(Bytecode::kWide);
+  } else if (operand_scale == 4) {
+    os << "." << Bytecodes::ToString(Bytecode::kExtraWide);
+  }
+  os << " ";
 
   // Operands for the debug break are from the original instruction.
   if (IsDebugBreak(bytecode)) return os;
@@ -428,42 +491,41 @@ std::ostream& Bytecodes::Decode(std::ostream& os, const uint8_t* bytecode_start,
   for (int i = 0; i < number_of_operands; i++) {
     OperandType op_type = GetOperandType(bytecode, i);
     const uint8_t* operand_start =
-        &bytecode_start[GetOperandOffset(bytecode, i)];
+        &bytecode_start[prefix_offset +
+                        GetOperandOffset(bytecode, i, operand_scale)];
     switch (op_type) {
-      case interpreter::OperandType::kRegCount8:
-        os << "#" << static_cast<unsigned int>(*operand_start);
-        break;
-      case interpreter::OperandType::kRegCount16:
-        os << '#' << ReadUnalignedUInt16(operand_start);
+      case interpreter::OperandType::kRegCount:
+        os << "#"
+           << DecodeUnsignedOperand(operand_start, op_type, operand_scale);
         break;
-      case interpreter::OperandType::kIdx8:
-        os << "[" << static_cast<unsigned int>(*operand_start) << "]";
+      case interpreter::OperandType::kIdx:
+      case interpreter::OperandType::kRuntimeId:
+        os << "["
+           << DecodeUnsignedOperand(operand_start, op_type, operand_scale)
+           << "]";
         break;
-      case interpreter::OperandType::kIdx16:
-        os << "[" << ReadUnalignedUInt16(operand_start) << "]";
+      case interpreter::OperandType::kImm:
+        os << "[" << DecodeSignedOperand(operand_start, op_type, operand_scale)
+           << "]";
         break;
-      case interpreter::OperandType::kImm8:
-        os << "#" << static_cast<int>(static_cast<int8_t>(*operand_start));
+      case interpreter::OperandType::kFlag8:
+        os << "#"
+           << DecodeUnsignedOperand(operand_start, op_type, operand_scale);
         break;
-      case interpreter::OperandType::kMaybeReg8:
-      case interpreter::OperandType::kMaybeReg16:
-      case interpreter::OperandType::kReg8:
-      case interpreter::OperandType::kReg16:
-      case interpreter::OperandType::kRegOut8:
-      case interpreter::OperandType::kRegOut16: {
-        Register reg = DecodeRegister(operand_start, op_type);
+      case interpreter::OperandType::kMaybeReg:
+      case interpreter::OperandType::kReg:
+      case interpreter::OperandType::kRegOut: {
+        Register reg = DecodeRegister(operand_start, op_type, operand_scale);
         os << reg.ToString(parameter_count);
         break;
       }
-      case interpreter::OperandType::kRegOutTriple8:
-      case interpreter::OperandType::kRegOutTriple16:
+      case interpreter::OperandType::kRegOutTriple:
         range += 1;
-      case interpreter::OperandType::kRegOutPair8:
-      case interpreter::OperandType::kRegOutPair16:
-      case interpreter::OperandType::kRegPair8:
-      case interpreter::OperandType::kRegPair16: {
+      case interpreter::OperandType::kRegOutPair:
+      case interpreter::OperandType::kRegPair: {
         range += 1;
-        Register first_reg = DecodeRegister(operand_start, op_type);
+        Register first_reg =
+            DecodeRegister(operand_start, op_type, operand_scale);
         Register last_reg = Register(first_reg.index() + range);
         os << first_reg.ToString(parameter_count) << "-"
            << last_reg.ToString(parameter_count);