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[analyzer][Solver] Improve getSymVal and friends (1/2) #112583

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Merged
merged 1 commit into from
Oct 18, 2024
Merged

[analyzer][Solver] Improve getSymVal and friends (1/2) #112583

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3 changes: 2 additions & 1 deletion clang/lib/StaticAnalyzer/Checkers/BitwiseShiftChecker.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -177,7 +177,8 @@ BugReportPtr BitwiseShiftValidator::checkOvershift() {
RightOpStr = formatv(" '{0}'", ConcreteRight->getValue());
else {
SValBuilder &SVB = Ctx.getSValBuilder();
if (const llvm::APSInt *MinRight = SVB.getMinValue(FoldedState, Right)) {
if (const llvm::APSInt *MinRight = SVB.getMinValue(FoldedState, Right);
MinRight && *MinRight >= LHSBitWidth) {
LowerBoundStr = formatv(" >= {0},", MinRight->getExtValue());
}
}
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21 changes: 8 additions & 13 deletions clang/lib/StaticAnalyzer/Core/RangeConstraintManager.cpp
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Expand Up @@ -1939,11 +1939,8 @@ class RangeConstraintManager : public RangedConstraintManager {
RangeSet::Factory F;

RangeSet getRange(ProgramStateRef State, SymbolRef Sym);
RangeSet getRange(ProgramStateRef State, EquivalenceClass Class);
ProgramStateRef setRange(ProgramStateRef State, SymbolRef Sym,
RangeSet Range);
ProgramStateRef setRange(ProgramStateRef State, EquivalenceClass Class,
RangeSet Range);

RangeSet getSymLTRange(ProgramStateRef St, SymbolRef Sym,
const llvm::APSInt &Int,
Expand Down Expand Up @@ -2866,24 +2863,22 @@ ConditionTruthVal RangeConstraintManager::checkNull(ProgramStateRef State,

const llvm::APSInt *RangeConstraintManager::getSymVal(ProgramStateRef St,
SymbolRef Sym) const {
const RangeSet *T = getConstraint(St, Sym);
return T ? T->getConcreteValue() : nullptr;
auto &MutableSelf = const_cast<RangeConstraintManager &>(*this);
return MutableSelf.getRange(St, Sym).getConcreteValue();
}

const llvm::APSInt *RangeConstraintManager::getSymMinVal(ProgramStateRef St,
SymbolRef Sym) const {
const RangeSet *T = getConstraint(St, Sym);
if (!T || T->isEmpty())
return nullptr;
return &T->getMinValue();
auto &MutableSelf = const_cast<RangeConstraintManager &>(*this);
RangeSet Range = MutableSelf.getRange(St, Sym);
return Range.isEmpty() ? nullptr : &Range.getMinValue();
}

const llvm::APSInt *RangeConstraintManager::getSymMaxVal(ProgramStateRef St,
SymbolRef Sym) const {
const RangeSet *T = getConstraint(St, Sym);
if (!T || T->isEmpty())
return nullptr;
return &T->getMaxValue();
auto &MutableSelf = const_cast<RangeConstraintManager &>(*this);
RangeSet Range = MutableSelf.getRange(St, Sym);
return Range.isEmpty() ? nullptr : &Range.getMaxValue();
}

//===----------------------------------------------------------------------===//
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29 changes: 4 additions & 25 deletions clang/test/Analysis/infeasible-sink.c
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Expand Up @@ -38,7 +38,7 @@ void test1(int x) {
}

int a, b, c, d, e;
void test2() {
void test2(void) {

if (a == 0)
return;
Expand All @@ -50,31 +50,10 @@ void test2() {
b = d;
a -= d;

if (a != 0)
return;

clang_analyzer_warnIfReached(); // expected-warning{{REACHABLE}}
clang_analyzer_warnIfReached(); // expected-warning {{REACHABLE}}

/* The BASELINE passes these checks ('wrning' is used to avoid lit to match)
// The parent state is already infeasible, look at this contradiction:
clang_analyzer_eval(b > 0); // expected-wrning{{FALSE}}
clang_analyzer_eval(b <= 0); // expected-wrning{{FALSE}}
// Crashes with expensive checks.
if (b > 0) {
clang_analyzer_warnIfReached(); // no-warning, OK
if (a != 0)
return;
}
// Should not be reachable.
clang_analyzer_warnIfReached(); // expected-wrning{{REACHABLE}}
*/

// The parent state is already infeasible, but we realize that only if b is
// constrained.
clang_analyzer_eval(b > 0); // expected-warning{{UNKNOWN}}
clang_analyzer_eval(b <= 0); // expected-warning{{UNKNOWN}}
if (b > 0) {
clang_analyzer_warnIfReached(); // no-warning
return;
}
clang_analyzer_warnIfReached(); // no-warning
clang_analyzer_warnIfReached(); // no-warning: Unreachable due to contradiction.
}
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