cerc-io/solidity
11
0
Fork 0
mirror of https://github.com/ethereum/solidity synced 2023-10-03 13:03:40 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

Use yul::AstWalker to resolve assembly symbols

Browse Source
This commit is contained in:
Mathias Baumann
2020-01-28 17:57:48 +01:00
committed by Mathias Baumann
parent 0dd398e2ac
commit b8e2baf5f4
8 changed files with 468 additions and 83 deletions
Download Patch File Download Diff File Expand all files Collapse all files
libsolidity/analysis/ReferencesResolver.cpp
+87 -80
View File
@@ -270,87 +270,10 @@ bool ReferencesResolver::visit(InlineAssembly const& _inlineAssembly)
{
m_resolver.warnVariablesNamedLikeInstructions();
// Errors created in this stage are completely ignored because we do not yet know
// the type and size of external identifiers, which would result in false errors.
// The only purpose of this step is to fill the inline assembly annotation with
// external references.
ErrorList errors;
ErrorReporter errorsIgnored(errors);
yul::ExternalIdentifierAccess::Resolver resolver =
[&](yul::Identifier const& _identifier, yul::IdentifierContext _context, bool _crossesFunctionBoundary) {
bool isSlot = boost::algorithm::ends_with(_identifier.name.str(), "_slot");
bool isOffset = boost::algorithm::ends_with(_identifier.name.str(), "_offset");
if (_context == yul::IdentifierContext::VariableDeclaration)
{
string namePrefix = _identifier.name.str().substr(0, _identifier.name.str().find('.'));
if (isSlot || isOffset)
declarationError(_identifier.location, "In variable declarations _slot and _offset can not be used as a suffix.");
else if (
auto declarations = m_resolver.nameFromCurrentScope(namePrefix);
!declarations.empty()
)
{
SecondarySourceLocation ssl;
for (auto const* decl: declarations)
ssl.append("The shadowed declaration is here:", decl->location());
if (!ssl.infos.empty())
declarationError(
_identifier.location,
ssl,
namePrefix.size() < _identifier.name.str().size() ?
"The prefix of this declaration conflicts with a declaration outside the inline assembly block." :
"This declaration shadows a declaration outside the inline assembly block."
);
}
return size_t(-1);
}
auto declarations = m_resolver.nameFromCurrentScope(_identifier.name.str());
if (isSlot || isOffset)
{
// special mode to access storage variables
if (!declarations.empty())
// the special identifier exists itself, we should not allow that.
return size_t(-1);
string realName = _identifier.name.str().substr(0, _identifier.name.str().size() - (
isSlot ?
string("_slot").size() :
string("_offset").size()
));
if (realName.empty())
{
declarationError(_identifier.location, "In variable names _slot and _offset can only be used as a suffix.");
return size_t(-1);
}
declarations = m_resolver.nameFromCurrentScope(realName);
}
if (declarations.size() > 1)
{
declarationError(_identifier.location, "Multiple matching identifiers. Resolving overloaded identifiers is not supported.");
return size_t(-1);
}
else if (declarations.size() == 0)
return size_t(-1);
if (auto var = dynamic_cast<VariableDeclaration const*>(declarations.front()))
if (var->isLocalVariable() && _crossesFunctionBoundary)
{
declarationError(_identifier.location, "Cannot access local Solidity variables from inside an inline assembly function.");
return size_t(-1);
}
_inlineAssembly.annotation().externalReferences[&_identifier].isSlot = isSlot;
_inlineAssembly.annotation().externalReferences[&_identifier].isOffset = isOffset;
_inlineAssembly.annotation().externalReferences[&_identifier].declaration = declarations.front();
return size_t(1);
};
m_yulAnnotation = &_inlineAssembly.annotation();
(*this)(_inlineAssembly.operations());
m_yulAnnotation = nullptr;
// Will be re-generated later with correct information
// We use the latest EVM version because we will re-run it anyway.
yul::AsmAnalysisInfo analysisInfo;
yul::AsmAnalyzer(
analysisInfo,
errorsIgnored,
yul::EVMDialect::strictAssemblyForEVM(m_evmVersion),
resolver
).analyze(_inlineAssembly.operations());
return false;
}
@@ -468,6 +391,90 @@ void ReferencesResolver::endVisit(VariableDeclaration const& _variable)
_variable.annotation().type = type;
}
void ReferencesResolver::operator()(yul::FunctionDefinition const& _function)
{
bool wasInsideFunction = m_yulInsideFunction;
m_yulInsideFunction = true;
this->operator()(_function.body);
m_yulInsideFunction = wasInsideFunction;
}
void ReferencesResolver::operator()(yul::Identifier const& _identifier)
{
bool isSlot = boost::algorithm::ends_with(_identifier.name.str(), "_slot");
bool isOffset = boost::algorithm::ends_with(_identifier.name.str(), "_offset");
auto declarations = m_resolver.nameFromCurrentScope(_identifier.name.str());
if (isSlot || isOffset)
{
// special mode to access storage variables
if (!declarations.empty())
// the special identifier exists itself, we should not allow that.
return;
string realName = _identifier.name.str().substr(0, _identifier.name.str().size() - (
isSlot ?
string("_slot").size() :
string("_offset").size()
));
if (realName.empty())
{
declarationError(_identifier.location, "In variable names _slot and _offset can only be used as a suffix.");
return;
}
declarations = m_resolver.nameFromCurrentScope(realName);
}
if (declarations.size() > 1)
{
declarationError(_identifier.location, "Multiple matching identifiers. Resolving overloaded identifiers is not supported.");
return;
}
else if (declarations.size() == 0)
return;
if (auto var = dynamic_cast<VariableDeclaration const*>(declarations.front()))
if (var->isLocalVariable() && m_yulInsideFunction)
{
declarationError(_identifier.location, "Cannot access local Solidity variables from inside an inline assembly function.");
return;
}
m_yulAnnotation->externalReferences[&_identifier].isSlot = isSlot;
m_yulAnnotation->externalReferences[&_identifier].isOffset = isOffset;
m_yulAnnotation->externalReferences[&_identifier].declaration = declarations.front();
}
void ReferencesResolver::operator()(yul::VariableDeclaration const& _varDecl)
{
for (auto const& identifier: _varDecl.variables)
{
bool isSlot = boost::algorithm::ends_with(identifier.name.str(), "_slot");
bool isOffset = boost::algorithm::ends_with(identifier.name.str(), "_offset");
string namePrefix = identifier.name.str().substr(0, identifier.name.str().find('.'));
if (isSlot || isOffset)
declarationError(identifier.location, "In variable declarations _slot and _offset can not be used as a suffix.");
else if (
auto declarations = m_resolver.nameFromCurrentScope(namePrefix);
!declarations.empty()
)
{
SecondarySourceLocation ssl;
for (auto const* decl: declarations)
ssl.append("The shadowed declaration is here:", decl->location());
if (!ssl.infos.empty())
declarationError(
identifier.location,
ssl,
namePrefix.size() < identifier.name.str().size() ?
"The prefix of this declaration conflicts with a declaration outside the inline assembly block." :
"This declaration shadows a declaration outside the inline assembly block."
);
}
}
if (_varDecl.value)
visit(*_varDecl.value);
}
void ReferencesResolver::typeError(SourceLocation const& _location, string const& _description)
{
m_errorOccurred = true;
libsolidity/analysis/ReferencesResolver.h
+12 -1
View File
@@ -25,6 +25,7 @@
#include <libsolidity/ast/ASTVisitor.h>
#include <libsolidity/ast/ASTAnnotations.h>
#include <liblangutil/EVMVersion.h>
#include <libyul/optimiser/ASTWalker.h>
#include <boost/noncopyable.hpp>
#include <list>
@@ -45,7 +46,7 @@ class NameAndTypeResolver;
* Resolves references to declarations (of variables and types) and also establishes the link
* between a return statement and the return parameter list.
*/
class ReferencesResolver: private ASTConstVisitor
class ReferencesResolver: private ASTConstVisitor, private yul::ASTWalker
{
public:
ReferencesResolver(
@@ -64,6 +65,9 @@ public:
bool resolve(ASTNode const& _root);
private:
using yul::ASTWalker::visit;
using yul::ASTWalker::operator();
bool visit(Block const& _block) override;
void endVisit(Block const& _block) override;
bool visit(ForStatement const& _for) override;
@@ -83,6 +87,10 @@ private:
bool visit(Return const& _return) override;
void endVisit(VariableDeclaration const& _variable) override;
void operator()(yul::FunctionDefinition const& _function) override;
void operator()(yul::Identifier const& _identifier) override;
void operator()(yul::VariableDeclaration const& _varDecl) override;
/// Adds a new error to the list of errors.
void typeError(langutil::SourceLocation const& _location, std::string const& _description);
@@ -105,6 +113,9 @@ private:
std::vector<ParameterList const*> m_returnParameters;
bool const m_resolveInsideCode;
bool m_errorOccurred = false;
InlineAssemblyAnnotation* m_yulAnnotation = nullptr;
bool m_yulInsideFunction = false;
};
}