Add builtin erc7201

libsolidity/analysis/ConstantEvaluator.cpp

@@ -26,6 +26,9 @@
 #include <libsolidity/ast/AST.h>
 #include <libsolidity/ast/TypeProvider.h>
 #include <liblangutil/ErrorReporter.h>
+#include <libsolutil/Keccak256.h>
+#include <libsolutil/StringUtils.h>
+#include <libsolutil/FixedHash.h>
 
 #include <limits>
 
@@ -407,3 +410,35 @@ void ConstantEvaluator::endVisit(TupleExpression const& _tuple)
 	if (!_tuple.isInlineArray() && _tuple.components().size() == 1)
 		m_values[&_tuple] = evaluate(*_tuple.components().front());
 }
+
+void ConstantEvaluator::endVisit(FunctionCall const& _functionCall)
+{
+	using util::keccak256;
+	using util::h256;
+
+	auto const* builtinFunction = dynamic_cast<MagicVariableDeclaration const*>(ASTNode::referencedDeclaration(_functionCall.expression()));
+	if (!builtinFunction)
+		return;
+
+	auto const* functionType = builtinFunction->functionType(true);
+	solAssert(functionType);
+	switch (functionType->kind())
+	{
+		case FunctionType::Kind::ERC7201:
+		{
+			solAssert(_functionCall.arguments().size() == 1);
+			auto const* argument = dynamic_cast<Literal const*>(_functionCall.arguments()[0].get());
+			solAssert(argument);
+			ASTString argStringLiteral = argument->valueWithoutUnderscores();
+			auto value =
+				u256(keccak256(h256(u256(keccak256(argStringLiteral)) - 1))) &
+				u256(~0xff)
+			;
+			solAssert(functionType->returnParameterTypes().size() == 1);
+			m_values[&_functionCall] = TypedRational{functionType->returnParameterTypes()[0], rational{value}};
+			break;
+		}
+		default:
+			break;
+	}
+}

libsolidity/analysis/ConstantEvaluator.h

@@ -79,6 +79,7 @@ class ConstantEvaluator: private ASTConstVisitor
 	void endVisit(Literal const& _literal) override;
 	void endVisit(Identifier const& _identifier) override;
 	void endVisit(TupleExpression const& _tuple) override;
+	void endVisit(FunctionCall const& _functionCall) override;
 
 	langutil::ErrorReporter& m_errorReporter;
 	/// Current recursion depth.

libsolidity/analysis/GlobalContext.cpp

@@ -62,7 +62,8 @@ int magicVariableToID(std::string const& _name)
 		{"tx", -26},
 		{"type", -27},
 		{"this", -28},
-		{"blobhash", -29}
+		{"blobhash", -29},
+		{"erc7201", -30}
 	};
 
 	if (auto id = magicVariables.find(_name); id != magicVariables.end())
@@ -83,6 +84,7 @@ inline std::vector<std::shared_ptr<MagicVariableDeclaration const>> constructMag
 		magicVarDecl("block", TypeProvider::magic(MagicType::Kind::Block)),
 		magicVarDecl("blockhash", TypeProvider::function(strings{"uint256"}, strings{"bytes32"}, FunctionType::Kind::BlockHash, StateMutability::View)),
 		magicVarDecl("ecrecover", TypeProvider::function(strings{"bytes32", "uint8", "bytes32", "bytes32"}, strings{"address"}, FunctionType::Kind::ECRecover, StateMutability::Pure)),
+		magicVarDecl("erc7201", TypeProvider::function(strings{"bytes memory"}, strings{"uint256"}, FunctionType::Kind::ERC7201, StateMutability::Pure)),
 		magicVarDecl("gasleft", TypeProvider::function(strings(), strings{"uint256"}, FunctionType::Kind::GasLeft, StateMutability::View)),
 		magicVarDecl("keccak256", TypeProvider::function(strings{"bytes memory"}, strings{"bytes32"}, FunctionType::Kind::KECCAK256, StateMutability::Pure)),
 		magicVarDecl("msg", TypeProvider::magic(MagicType::Kind::Message)),

libsolidity/analysis/PostTypeContractLevelChecker.cpp

@@ -91,7 +91,6 @@ void PostTypeContractLevelChecker::checkStorageLayoutSpecifier(ContractDefinitio
 
 	if (!*baseSlotExpression.annotation().isPure)
 	{
-		// TODO: introduce and handle erc7201 as a builtin function
 		m_errorReporter.typeError(
 			1139_error,
 			baseSlotExpression.location(),

libsolidity/ast/Types.cpp

@@ -3125,6 +3125,7 @@ std::string FunctionType::richIdentifier() const
 	case Kind::ABIDecode: id += "abidecode"; break;
 	case Kind::BlobHash: id += "blobhash"; break;
 	case Kind::MetaType: id += "metatype"; break;
+	case Kind::ERC7201: id += "erc7201"; break;
 	}
 	id += "_" + stateMutabilityToString(m_stateMutability);
 	id += identifierList(m_parameterTypes) + "returns" + identifierList(m_returnParameterTypes);
@@ -3713,7 +3714,8 @@ bool FunctionType::isPure() const
 		m_kind == Kind::ABIDecode ||
 		m_kind == Kind::MetaType ||
 		m_kind == Kind::Wrap ||
-		m_kind == Kind::Unwrap;
+		m_kind == Kind::Unwrap ||
+		m_kind == Kind::ERC7201;
 }
 
 TypePointers FunctionType::parseElementaryTypeVector(strings const& _types)

libsolidity/ast/Types.h

@@ -1297,6 +1297,7 @@ class FunctionType: public Type
 		ABIDecode,
 		GasLeft, ///< gasleft()
 		MetaType, ///< type(...)
+		ERC7201, ///< erc7201(...)
 		/// Refers to a function declaration without calling context
 		/// (i.e. when accessed directly via the name of the containing contract).
 		/// Cannot be called.

libsolidity/codegen/ExpressionCompiler.cpp

@@ -1521,6 +1521,9 @@ bool ExpressionCompiler::visit(FunctionCall const& _functionCall)
 		case FunctionType::Kind::MetaType:
 			// No code to generate.
 			break;
+		case FunctionType::Kind::ERC7201:
+			solUnimplementedAssert(false, "Codegen does not support erc7201 builtin yet.");
+			break;
 		}
 	}
 	return false;

test/libsolidity/syntaxTests/constantEvaluator/erc7201_builtin.sol

@@ -0,0 +1,6 @@
+contract C {
+    uint constant x = erc7201("A");
+    uint[x] array;
+}
+// ----
+// Warning 7325: (53-60): Type uint256[36579005187129934694193755934841191771209741707776365283473783080460440925696] covers a large part of storage and thus makes collisions likely. Either use mappings or dynamic arrays and allow their size to be increased only in small quantities per transaction.

test/libsolidity/syntaxTests/globalFunctions/erc7201_builtin.sol

@@ -0,0 +1,7 @@
+contract C {
+    function f() public pure returns (uint) {
+        return erc7201("ABC");
+    }
+}
+// ----
+// UnimplementedFeatureError 1834: (0-97): Codegen does not support erc7201 builtin yet.

test/libsolidity/syntaxTests/globalFunctions/erc7201_builtin_function_shadow_warning.sol

@@ -0,0 +1,5 @@
+function erc7201() pure returns (uint) {
+    return 42;
+}
+// ----
+// Warning 2319: (0-57): This declaration shadows a builtin symbol.

test/libsolidity/syntaxTests/globalFunctions/erc7201_builtin_no_call.sol

@@ -0,0 +1,7 @@
+contract C {
+    function f() public pure {
+        erc7201;
+    }
+}
+// ----
+// Warning 6133: (52-59): Statement has no effect.

test/libsolidity/syntaxTests/globalFunctions/erc7201_builtin_var_shadow_warning.sol

@@ -0,0 +1,5 @@
+contract C {
+    uint erc7201;
+}
+// ----
+// Warning 2319: (17-29): This declaration shadows a builtin symbol.

test/libsolidity/syntaxTests/globalFunctions/erc7201_builtin_with_wrong_arg_count.sol

@@ -0,0 +1,9 @@
+contract C {
+    uint x = erc7201();
+    uint y = erc7201("12", "34");
+    uint z = erc7201("A", "BC", "D");
+}
+// ----
+// TypeError 6160: (26-35): Wrong argument count for function call: 0 arguments given but expected 1.
+// TypeError 6160: (50-69): Wrong argument count for function call: 2 arguments given but expected 1.
+// TypeError 6160: (84-107): Wrong argument count for function call: 3 arguments given but expected 1.

test/libsolidity/syntaxTests/nameAndTypeResolution/assignment_to_const_var_involving_erc7201.sol

@@ -0,0 +1,8 @@
+contract C {
+    uint constant x = erc7201("abc");
+    function f() public pure returns(uint) {
+        return x;
+    }
+}
+// ----
+// UnimplementedFeatureError 1834: (0-121): Codegen does not support erc7201 builtin yet.

test/libsolidity/syntaxTests/nameAndTypeResolution/builtin_erc7201_reject_gas.sol

@@ -0,0 +1,7 @@
+contract C {
+    function f() public {
+        erc7201.gas();
+    }
+}
+// ----
+// TypeError 9582: (47-58): Member "gas" not found or not visible after argument-dependent lookup in function (bytes memory) pure returns (uint256).

test/libsolidity/syntaxTests/nameAndTypeResolution/builtin_erc7201_reject_value.sol

@@ -0,0 +1,7 @@
+contract C {
+    function f() public {
+        erc7201.value();
+    }
+}
+// ----
+// TypeError 8820: (47-60): Member "value" is only available for payable functions.