Files
codeql/csharp/ql/test/library-tests/dataflow/defuse/parameterUseEquivalence.ql
2025-12-11 14:17:12 +01:00

44 lines
1.3 KiB
Plaintext

import csharp
private import semmle.code.csharp.dataflow.internal.BaseSSA
/** "Naive" parameter-use implementation. */
predicate parameterReaches(Parameter p, ControlFlow::Node cfn) {
cfn = p.getCallable().getEntryPoint().getASuccessor() and
p instanceof BaseSsa::SimpleLocalScopeVariable
or
exists(ControlFlow::Node mid | parameterReaches(p, mid) |
not mid =
any(AssignableDefinition ad | ad.getTarget() = p and ad.isCertain())
.getExpr()
.getAControlFlowNode() and
cfn = mid.getASuccessor()
)
}
predicate parameterUsePair(Parameter p, AssignableRead read) {
parameterReaches(p, read.getAControlFlowNode()) and
read.getTarget() = p
}
private LocalScopeVariableRead getAReachableUncertainRead(
AssignableDefinitions::ImplicitParameterDefinition p
) {
exists(Ssa::Definition ssaDef |
p.getParameter() =
ssaDef.getAnUltimateDefinition().(Ssa::ImplicitParameterDefinition).getParameter()
|
result = ssaDef.getARead()
)
}
from AssignableDefinitions::ImplicitParameterDefinition p, AssignableRead read, string s
where
read = getAReachableUncertainRead(p) and
not parameterUsePair(p.getParameter(), read) and
s = "not a param/use pair"
or
parameterUsePair(p.getParameter(), read) and
not read = getAReachableUncertainRead(p) and
s = "missing param/use pair"
select p, read, s