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Removed SHR (>>>) operator #15848

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Removed SHR (>>>) operator #15848

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d3bca85
Removed SHR (>>>) operator
yash-sethi-24 Feb 11, 2025
bb30a90
Remove unused _operator argument from isValidShiftAndAmountType and c…
yash-sethi-24 Feb 18, 2025
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2 changes: 0 additions & 2 deletions docs/grammar/SolidityLexer.g4
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Original file line number Diff line number Diff line change
Expand Up @@ -125,7 +125,6 @@ AssignBitXor: '^=';
AssignBitAnd: '&=';
AssignShl: '<<=';
AssignSar: '>>=';
AssignShr: '>>>=';
AssignAdd: '+=';
AssignSub: '-=';
AssignMul: '*=';
Expand All @@ -140,7 +139,6 @@ BitXor: '^';
BitAnd: '&';
Shl: '<<';
Sar: '>>';
Shr: '>>>';
Add: '+';
Sub: '-';
Mul: '*';
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2 changes: 1 addition & 1 deletion docs/grammar/SolidityParser.g4
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Expand Up @@ -410,7 +410,7 @@ expression:
;

//@doc:inline
assignOp: Assign | AssignBitOr | AssignBitXor | AssignBitAnd | AssignShl | AssignSar | AssignShr | AssignAdd | AssignSub | AssignMul | AssignDiv | AssignMod;
assignOp: Assign | AssignBitOr | AssignBitXor | AssignBitAnd | AssignShl | AssignSar | AssignAdd | AssignSub | AssignMul | AssignDiv | AssignMod;
tupleExpression: LParen (expression? ( Comma expression?)* ) RParen;
/**
* An inline array expression denotes a statically sized array of the common type of the contained expressions.
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6 changes: 2 additions & 4 deletions liblangutil/Scanner.cpp
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Expand Up @@ -562,18 +562,16 @@ void Scanner::scanToken()
token = Token::LessThan;
break;
case '>':
// > >= >> >>= >>> >>>=
// > >= >> >>=
advance();
if (m_char == '=')
token = selectToken(Token::GreaterThanOrEqual);
else if (m_char == '>')
{
// >> >>= >>> >>>=
// >> >>=
advance();
if (m_char == '=')
token = selectToken(Token::AssignSar);
else if (m_char == '>')
token = selectToken('=', Token::AssignShr, Token::SHR);
else
token = Token::SAR;
}
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4 changes: 1 addition & 3 deletions liblangutil/Token.h
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Expand Up @@ -93,7 +93,6 @@ namespace solidity::langutil
T(AssignBitAnd, "&=", 2) \
T(AssignShl, "<<=", 2) \
T(AssignSar, ">>=", 2) \
T(AssignShr, ">>>=", 2) \
T(AssignAdd, "+=", 2) \
T(AssignSub, "-=", 2) \
T(AssignMul, "*=", 2) \
Expand All @@ -111,7 +110,6 @@ namespace solidity::langutil
T(BitAnd, "&", 10) \
T(SHL, "<<", 11) \
T(SAR, ">>", 11) \
T(SHR, ">>>", 11) \
T(Add, "+", 12) \
T(Sub, "-", 12) \
T(Mul, "*", 13) \
Expand Down Expand Up @@ -314,7 +312,7 @@ namespace TokenTraits
constexpr bool isBooleanOp(Token op) { return (Token::Or <= op && op <= Token::And) || op == Token::Not; }
constexpr bool isUnaryOp(Token op) { return (Token::Not <= op && op <= Token::Delete) || op == Token::Sub; }
constexpr bool isCountOp(Token op) { return op == Token::Inc || op == Token::Dec; }
constexpr bool isShiftOp(Token op) { return (Token::SHL <= op) && (op <= Token::SHR); }
constexpr bool isShiftOp(Token op) { return op == Token::SHL; }
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@clonker clonker Aug 7, 2025

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This ignores SAR - interesting, that this didn't break anything else :)

constexpr bool isVariableVisibilitySpecifier(Token op) { return op == Token::Public || op == Token::Private || op == Token::Internal; }
constexpr bool isVisibilitySpecifier(Token op) { return isVariableVisibilitySpecifier(op) || op == Token::External; }
constexpr bool isLocationSpecifier(Token op) { return op == Token::Memory || op == Token::Storage || op == Token::CallData; }
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14 changes: 6 additions & 8 deletions libsolidity/ast/Types.cpp
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Expand Up @@ -571,12 +571,10 @@ MemberList::MemberMap AddressType::nativeMembers(ASTNode const*) const
namespace
{

bool isValidShiftAndAmountType(Token _operator, Type const& _shiftAmountType)
bool isValidShiftAndAmountType(Type const& _shiftAmountType)
{
// Disable >>> here.
if (_operator == Token::SHR)
return false;
else if (IntegerType const* otherInt = dynamic_cast<decltype(otherInt)>(&_shiftAmountType))

if (IntegerType const* otherInt = dynamic_cast<decltype(otherInt)>(&_shiftAmountType))
return !otherInt->isSigned();
else if (RationalNumberType const* otherRat = dynamic_cast<decltype(otherRat)>(&_shiftAmountType))
return !otherRat->isFractional() && otherRat->integerType() && !otherRat->integerType()->isSigned();
Expand Down Expand Up @@ -718,7 +716,7 @@ TypeResult IntegerType::binaryOperatorResult(Token _operator, Type const* _other
if (TokenTraits::isShiftOp(_operator))
{
// Shifts are not symmetric with respect to the type
if (isValidShiftAndAmountType(_operator, *_other))
if (isValidShiftAndAmountType(*_other))
return this;
else
return nullptr;
Expand Down Expand Up @@ -1084,7 +1082,7 @@ TypeResult RationalNumberType::binaryOperatorResult(Token _operator, Type const*
// the types as below. As an exception, we always use uint here.
if (TokenTraits::isShiftOp(_operator))
{
if (!isValidShiftAndAmountType(_operator, *_other))
if (!isValidShiftAndAmountType(*_other))
return nullptr;
return isNegative() ? TypeProvider::int256() : TypeProvider::uint256();
}
Expand Down Expand Up @@ -1386,7 +1384,7 @@ TypeResult FixedBytesType::binaryOperatorResult(Token _operator, Type const* _ot
{
if (TokenTraits::isShiftOp(_operator))
{
if (isValidShiftAndAmountType(_operator, *_other))
if (isValidShiftAndAmountType(*_other))
return this;
else
return nullptr;
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1 change: 0 additions & 1 deletion libsolidity/codegen/ExpressionCompiler.cpp
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Expand Up @@ -2662,7 +2662,6 @@ void ExpressionCompiler::appendShiftOperatorCode(Token _operator, Type const& _v

}
break;
case Token::SHR:
default:
solAssert(false, "Unknown shift operator.");
}
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5 changes: 0 additions & 5 deletions libsolidity/formal/SMTEncoder.cpp
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Expand Up @@ -1941,7 +1941,6 @@ smtutil::Expression SMTEncoder::bitwiseOperation(
Token::BitOr,
Token::BitXor,
Token::SHL,
Token::SHR,
Token::SAR
};
solAssert(validOperators.count(_op), "");
Expand All @@ -1967,9 +1966,6 @@ smtutil::Expression SMTEncoder::bitwiseOperation(
case Token::SHL:
result = bvLeft << bvRight;
break;
case Token::SHR:
result = bvLeft >> bvRight;
break;
case Token::SAR:
result = isSigned ?
smtutil::Expression::ashr(bvLeft, bvRight) :
Expand Down Expand Up @@ -2233,7 +2229,6 @@ smtutil::Expression SMTEncoder::compoundAssignment(Assignment const& _assignment
{Token::AssignBitOr, Token::BitOr},
{Token::AssignBitXor, Token::BitXor},
{Token::AssignShl, Token::SHL},
{Token::AssignShr, Token::SHR},
{Token::AssignSar, Token::SAR}
};
Token op = _assignment.assignmentOperator();
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6 changes: 2 additions & 4 deletions test/liblangutil/Scanner.cpp
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Expand Up @@ -454,7 +454,8 @@ BOOST_AUTO_TEST_CASE(locations)
BOOST_AUTO_TEST_CASE(ambiguities)
{
// test scanning of some operators which need look-ahead
TestScanner scanner("<=" "<" "+ +=a++ =>" "<<" ">>" " >>=" ">>>" ">>>=" " >>>>>=><<=");
TestScanner scanner("<=" "<" "+ +=a++ =>" "<<" ">>" " >>=");
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@clonker clonker Aug 7, 2025

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this simply removes the "monster" test case instead of adopting it to a form in which it is still meaningful without SHR


BOOST_CHECK_EQUAL(scanner.currentToken(), Token::LessThanOrEqual);
BOOST_CHECK_EQUAL(scanner.next(), Token::LessThan);
BOOST_CHECK_EQUAL(scanner.next(), Token::Add);
Expand All @@ -465,10 +466,7 @@ BOOST_AUTO_TEST_CASE(ambiguities)
BOOST_CHECK_EQUAL(scanner.next(), Token::SHL);
BOOST_CHECK_EQUAL(scanner.next(), Token::SAR);
BOOST_CHECK_EQUAL(scanner.next(), Token::AssignSar);
BOOST_CHECK_EQUAL(scanner.next(), Token::SHR);
BOOST_CHECK_EQUAL(scanner.next(), Token::AssignShr);
// the last "monster" token combination
BOOST_CHECK_EQUAL(scanner.next(), Token::SHR);
BOOST_CHECK_EQUAL(scanner.next(), Token::AssignSar);
BOOST_CHECK_EQUAL(scanner.next(), Token::GreaterThan);
BOOST_CHECK_EQUAL(scanner.next(), Token::AssignShl);
Expand Down