Add REVERT to libevmasm

Author: axic

libevmasm/GasMeter.cpp

@@ -80,6 +80,7 @@ GasMeter::GasConsumption GasMeter::estimateMax(AssemblyItem const& _item, bool _
 			gas += GasCosts::sloadGas;
 			break;
 		case Instruction::RETURN:
+		case Instruction::REVERT:
 			gas += memoryGas(0, -1);
 			break;
 		case Instruction::MLOAD:

libevmasm/Instruction.cpp

@@ -159,6 +159,7 @@ const std::map<std::string, Instruction> dev::solidity::c_instructions =
 	{ "CALLCODE", Instruction::CALLCODE },
 	{ "RETURN", Instruction::RETURN },
 	{ "DELEGATECALL", Instruction::DELEGATECALL },
+	{ "REVERT", Instruction::REVERT },
 	{ "INVALID", Instruction::INVALID },
 	{ "SELFDESTRUCT", Instruction::SELFDESTRUCT }
 };
@@ -294,6 +295,7 @@ static const std::map<Instruction, InstructionInfo> c_instructionInfo =
 	{ Instruction::CALLCODE,	{ "CALLCODE",		0, 7, 1, true, Tier::Special } },
 	{ Instruction::RETURN,		{ "RETURN",			0, 2, 0, true, Tier::Zero } },
 	{ Instruction::DELEGATECALL,	{ "DELEGATECALL",	0, 6, 1, true, Tier::Special } },
+	{ Instruction::REVERT,          { "REVERT",             0, 2, 0, true, Tier::Zero } },
 	{ Instruction::INVALID,		{ "INVALID",		0, 0, 0, true, Tier::Zero } },
 	{ Instruction::SELFDESTRUCT,	{ "SELFDESTRUCT",		0, 1, 0, true, Tier::Zero } }
 };

libevmasm/Instruction.h

@@ -177,6 +177,7 @@ enum class Instruction: uint8_t
 	RETURN,				///< halt execution returning output data
 	DELEGATECALL,		///< like CALLCODE but keeps caller's value and sender
 
+	REVERT = 0xfd,		///< halt execution, revert state and return output data
 	INVALID = 0xfe,		///< invalid instruction for expressing runtime errors (e.g., division-by-zero)
 	SELFDESTRUCT = 0xff	///< halt execution and register account for later deletion
 };

libevmasm/PeepholeOptimiser.cpp

@@ -200,7 +200,8 @@ struct UnreachableCode
 			it[0] != Instruction::RETURN &&
 			it[0] != Instruction::STOP &&
 			it[0] != Instruction::INVALID &&
-			it[0] != Instruction::SELFDESTRUCT
+			it[0] != Instruction::SELFDESTRUCT &&
+			it[0] != Instruction::REVERT
 		)
 			return false;
 

libevmasm/SemanticInformation.cpp

@@ -119,6 +119,7 @@ bool SemanticInformation::altersControlFlow(AssemblyItem const& _item)
 	case Instruction::SELFDESTRUCT:
 	case Instruction::STOP:
 	case Instruction::INVALID:
+	case Instruction::REVERT:
 		return true;
 	default:
 		return false;