4 files changed, 143 insertions, 79 deletions

diff --git a/libsolidity/interface/CompilerStack.cpp b/libsolidity/interface/CompilerStack.cpp
index 9ad28573..92b49cda 100644
--- a/libsolidity/interface/CompilerStack.cpp
+++ b/libsolidity/interface/CompilerStack.cpp
@@ -38,6 +38,7 @@
 #include <libsolidity/analysis/SyntaxChecker.h>
 #include <libsolidity/codegen/Compiler.h>
 #include <libsolidity/interface/InterfaceHandler.h>
+#include <libsolidity/interface/GasEstimator.h>
 #include <libsolidity/formal/Why3Translator.h>
 
 #include <libevmasm/Exceptions.h>
@@ -841,3 +842,88 @@ string CompilerStack::computeSourceMapping(eth::AssemblyItems const& _items) con
 	}
 	return ret;
 }
+
+namespace
+{
+
+Json::Value gasToJson(GasEstimator::GasConsumption const& _gas)
+{
+	if (_gas.isInfinite)
+		return Json::Value("infinite");
+	else
+		return Json::Value(toString(_gas.value));
+}
+
+}
+
+Json::Value CompilerStack::gasEstimates(string const& _contractName) const
+{
+	if (!assemblyItems(_contractName) && !runtimeAssemblyItems(_contractName))
+		return Json::Value();
+
+	using Gas = GasEstimator::GasConsumption;
+	Json::Value output(Json::objectValue);
+
+	if (eth::AssemblyItems const* items = assemblyItems(_contractName))
+	{
+		Gas executionGas = GasEstimator::functionalEstimation(*items);
+		u256 bytecodeSize(runtimeObject(_contractName).bytecode.size());
+		Gas codeDepositGas = bytecodeSize * eth::GasCosts::createDataGas;
+
+		Json::Value creation(Json::objectValue);
+		creation["codeDepositCost"] = gasToJson(codeDepositGas);
+		creation["executionCost"] = gasToJson(executionGas);
+		/// TODO: implement + overload to avoid the need of +=
+		executionGas += codeDepositGas;
+		creation["totalCost"] = gasToJson(executionGas);
+		output["creation"] = creation;
+	}
+
+	if (eth::AssemblyItems const* items = runtimeAssemblyItems(_contractName))
+	{
+		/// External functions
+		ContractDefinition const& contract = contractDefinition(_contractName);
+		Json::Value externalFunctions(Json::objectValue);
+		for (auto it: contract.interfaceFunctions())
+		{
+			string sig = it.second->externalSignature();
+			externalFunctions[sig] = gasToJson(GasEstimator::functionalEstimation(*items, sig));
+		}
+
+		if (contract.fallbackFunction())
+			/// This needs to be set to an invalid signature in order to trigger the fallback,
+			/// without the shortcut (of CALLDATSIZE == 0), and therefore to receive the upper bound.
+			/// An empty string ("") would work to trigger the shortcut only.
+			externalFunctions[""] = gasToJson(GasEstimator::functionalEstimation(*items, "INVALID"));
+
+		if (!externalFunctions.empty())
+			output["external"] = externalFunctions;
+
+		/// Internal functions
+		Json::Value internalFunctions(Json::objectValue);
+		for (auto const& it: contract.definedFunctions())
+		{
+			/// Exclude externally visible functions, constructor and the fallback function
+			if (it->isPartOfExternalInterface() || it->isConstructor() || it->name().empty())
+				continue;
+
+			size_t entry = functionEntryPoint(_contractName, *it);
+			GasEstimator::GasConsumption gas = GasEstimator::GasConsumption::infinite();
+			if (entry > 0)
+				gas = GasEstimator::functionalEstimation(*items, entry, *it);
+
+			FunctionType type(*it);
+			string sig = it->name() + "(";
+			auto paramTypes = type.parameterTypes();
+			for (auto it = paramTypes.begin(); it != paramTypes.end(); ++it)
+				sig += (*it)->toString() + (it + 1 == paramTypes.end() ? "" : ",");
+			sig += ")";
+			internalFunctions[sig] = gasToJson(gas);
+		}
+
+		if (!internalFunctions.empty())
+			output["internal"] = internalFunctions;
+	}
+
+	return output;
+}
diff --git a/libsolidity/interface/CompilerStack.h b/libsolidity/interface/CompilerStack.h
index 9c37eead..a34a34bb 100644
--- a/libsolidity/interface/CompilerStack.h
+++ b/libsolidity/interface/CompilerStack.h
@@ -173,6 +173,9 @@ public:
 	std::string const& onChainMetadata(std::string const& _contractName) const;
 	void useMetadataLiteralSources(bool _metadataLiteralSources) { m_metadataLiteralSources = _metadataLiteralSources; }
 
+	/// @returns a JSON representing the estimated gas usage for contract creation, internal and external functions
+	Json::Value gasEstimates(std::string const& _contractName) const;
+
 	/// @returns the previously used scanner, useful for counting lines during error reporting.
 	Scanner const& scanner(std::string const& _sourceName = "") const;
 	/// @returns the parsed source unit with the supplied name.
diff --git a/solc/CommandLineInterface.cpp b/solc/CommandLineInterface.cpp
index f0b73152..947a2004 100644
--- a/solc/CommandLineInterface.cpp
+++ b/solc/CommandLineInterface.cpp
@@ -315,49 +315,40 @@ void CommandLineInterface::handleMeta(DocumentationType _type, string const& _co
 
 void CommandLineInterface::handleGasEstimation(string const& _contract)
 {
-	using Gas = GasEstimator::GasConsumption;
-	if (!m_compiler->assemblyItems(_contract) && !m_compiler->runtimeAssemblyItems(_contract))
-		return;
+	Json::Value estimates = m_compiler->gasEstimates(_contract);
 	cout << "Gas estimation:" << endl;
-	if (eth::AssemblyItems const* items = m_compiler->assemblyItems(_contract))
+
+	if (estimates["creation"].isObject())
 	{
-		Gas gas = GasEstimator::functionalEstimation(*items);
-		u256 bytecodeSize(m_compiler->runtimeObject(_contract).bytecode.size());
+		Json::Value creation = estimates["creation"];
 		cout << "construction:" << endl;
-		cout << "   " << gas << " + " << (bytecodeSize * eth::GasCosts::createDataGas) << " = ";
-		gas += bytecodeSize * eth::GasCosts::createDataGas;
-		cout << gas << endl;
+		cout << "   " << creation["executionCost"].asString();
+		cout << " + " << creation["codeDepositCost"].asString();
+		cout << " = " << creation["totalCost"].asString() << endl;
 	}
-	if (eth::AssemblyItems const* items = m_compiler->runtimeAssemblyItems(_contract))
+
+	if (estimates["external"].isObject())
 	{
-		ContractDefinition const& contract = m_compiler->contractDefinition(_contract);
+		Json::Value externalFunctions = estimates["external"];
 		cout << "external:" << endl;
-		for (auto it: contract.interfaceFunctions())
-		{
-			string sig = it.second->externalSignature();
-			GasEstimator::GasConsumption gas = GasEstimator::functionalEstimation(*items, sig);
-			cout << "   " << sig << ":\t" << gas << endl;
-		}
-		if (contract.fallbackFunction())
+		for (auto const& name: externalFunctions.getMemberNames())
 		{
-			GasEstimator::GasConsumption gas = GasEstimator::functionalEstimation(*items, "INVALID");
-			cout << "   fallback:\t" << gas << endl;
+			if (name.empty())
+				cout << "   fallback:\t";
+			else
+				cout << "   " << name << ":\t";
+			cout << externalFunctions[name].asString() << endl;
 		}
+	}
+
+	if (estimates["internal"].isObject())
+	{
+		Json::Value internalFunctions = estimates["internal"];
 		cout << "internal:" << endl;
-		for (auto const& it: contract.definedFunctions())
+		for (auto const& name: internalFunctions.getMemberNames())
 		{
-			if (it->isPartOfExternalInterface() || it->isConstructor())
-				continue;
-			size_t entry = m_compiler->functionEntryPoint(_contract, *it);
-			GasEstimator::GasConsumption gas = GasEstimator::GasConsumption::infinite();
-			if (entry > 0)
-				gas = GasEstimator::functionalEstimation(*items, entry, *it);
-			FunctionType type(*it);
-			cout << "   " << it->name() << "(";
-			auto paramTypes = type.parameterTypes();
-			for (auto it = paramTypes.begin(); it != paramTypes.end(); ++it)
-				cout << (*it)->toString() << (it + 1 == paramTypes.end() ? "" : ",");
-			cout << "):\t" << gas << endl;
+			cout << "   " << name << ":\t";
+			cout << internalFunctions[name].asString() << endl;
 		}
 	}
 }
diff --git a/solc/jsonCompiler.cpp b/solc/jsonCompiler.cpp
index 065716ea..fd375ce3 100644
--- a/solc/jsonCompiler.cpp
+++ b/solc/jsonCompiler.cpp
@@ -58,61 +58,45 @@ Json::Value functionHashes(ContractDefinition const& _contract)
 	return functionHashes;
 }
 
-Json::Value gasToJson(GasEstimator::GasConsumption const& _gas)
+/// Translates a gas value as a string to a JSON number or null
+Json::Value gasToJson(Json::Value const& _value)
 {
-	if (_gas.isInfinite || _gas.value > std::numeric_limits<Json::LargestUInt>::max())
+	if (_value.isObject())
+	{
+		Json::Value ret = Json::objectValue;
+		for (auto const& sig: _value.getMemberNames())
+			ret[sig] = gasToJson(_value[sig]);
+		return ret;
+	}
+
+	if (_value == "infinite")
+		return Json::Value(Json::nullValue);
+
+	u256 value(_value.asString());
+	if (value > std::numeric_limits<Json::LargestUInt>::max())
 		return Json::Value(Json::nullValue);
 	else
-		return Json::Value(Json::LargestUInt(_gas.value));
+		return Json::Value(Json::LargestUInt(value));
 }
 
 Json::Value estimateGas(CompilerStack const& _compiler, string const& _contract)
 {
-	Json::Value gasEstimates(Json::objectValue);
-	using Gas = GasEstimator::GasConsumption;
-	if (!_compiler.assemblyItems(_contract) && !_compiler.runtimeAssemblyItems(_contract))
-		return gasEstimates;
-	if (eth::AssemblyItems const* items = _compiler.assemblyItems(_contract))
-	{
-		Gas gas = GasEstimator::functionalEstimation(*items);
-		u256 bytecodeSize(_compiler.runtimeObject(_contract).bytecode.size());
-		Json::Value creationGas(Json::arrayValue);
-		creationGas[0] = gasToJson(gas);
-		creationGas[1] = gasToJson(bytecodeSize * eth::GasCosts::createDataGas);
-		gasEstimates["creation"] = creationGas;
-	}
-	if (eth::AssemblyItems const* items = _compiler.runtimeAssemblyItems(_contract))
+	Json::Value estimates = _compiler.gasEstimates(_contract);
+	Json::Value output(Json::objectValue);
+
+	if (estimates["creation"].isObject())
 	{
-		ContractDefinition const& contract = _compiler.contractDefinition(_contract);
-		Json::Value externalFunctions(Json::objectValue);
-		for (auto it: contract.interfaceFunctions())
-		{
-			string sig = it.second->externalSignature();
-			externalFunctions[sig] = gasToJson(GasEstimator::functionalEstimation(*items, sig));
-		}
-		if (contract.fallbackFunction())
-			externalFunctions[""] = gasToJson(GasEstimator::functionalEstimation(*items, "INVALID"));
-		gasEstimates["external"] = externalFunctions;
-		Json::Value internalFunctions(Json::objectValue);
-		for (auto const& it: contract.definedFunctions())
-		{
-			if (it->isPartOfExternalInterface() || it->isConstructor())
-				continue;
-			size_t entry = _compiler.functionEntryPoint(_contract, *it);
-			GasEstimator::GasConsumption gas = GasEstimator::GasConsumption::infinite();
-			if (entry > 0)
-				gas = GasEstimator::functionalEstimation(*items, entry, *it);
-			FunctionType type(*it);
-			string sig = it->name() + "(";
-			auto paramTypes = type.parameterTypes();
-			for (auto it = paramTypes.begin(); it != paramTypes.end(); ++it)
-				sig += (*it)->toString() + (it + 1 == paramTypes.end() ? "" : ",");
-			sig += ")";
-			internalFunctions[sig] = gasToJson(gas);
-		}
-		gasEstimates["internal"] = internalFunctions;
+		Json::Value creation(Json::arrayValue);
+		creation[0] = gasToJson(estimates["creation"]["executionCost"]);
+		creation[1] = gasToJson(estimates["creation"]["codeDepositCost"]);
+		output["creation"] = creation;
 	}
-	return gasEstimates;
+	else
+		output["creation"] = Json::objectValue;
+	output["external"] = gasToJson(estimates.get("external", Json::objectValue));
+	output["internal"] = gasToJson(estimates.get("internal", Json::objectValue));
+
+	return output;
 }
 
 string compile(StringMap const& _sources, bool _optimize, CStyleReadFileCallback _readCallback)