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Fix 10944: FN: knownConditionTrueFalse (#4124) 

* Fix 10944: FN: knownConditionTrueFalse

* Use or

* Format
This commit is contained in:
Paul Fultz II 2022-05-23 16:22:08 -05:00 committed by GitHub
parent 1ced94be43
commit 5999b35130
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2 changed files with 76 additions and 47 deletions
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109
lib/valueflow.cpp
View File

@ -937,53 +937,6 @@ static void setTokenValue(Token* tok, ValueFlow::Value value, const Settings* se
}
}
// Array element
else if (parent->str() == "[" && parent->isBinaryOp()) {
for (const ValueFlow::Value &value1 : parent->astOperand1()->values()) {
if (!value1.isTokValue())
continue;
for (const ValueFlow::Value &value2 : parent->astOperand2()->values()) {
if (!value2.isIntValue())
continue;
if (value1.varId == 0 || value2.varId == 0 ||
(value1.varId == value2.varId && value1.varvalue == value2.varvalue)) {
ValueFlow::Value result(0);
result.condition = value1.condition ? value1.condition : value2.condition;
result.setInconclusive(value1.isInconclusive() | value2.isInconclusive());
result.varId = (value1.varId != 0) ? value1.varId : value2.varId;
result.varvalue = (result.varId == value1.varId) ? value1.intvalue : value2.intvalue;
if (value1.valueKind == value2.valueKind)
result.valueKind = value1.valueKind;
if (value1.tokvalue->tokType() == Token::eString) {
const std::string s = value1.tokvalue->strValue();
const MathLib::bigint index = value2.intvalue;
if (index == s.size()) {
result.intvalue = 0;
setTokenValue(parent, result, settings);
} else if (index >= 0 && index < s.size()) {
result.intvalue = s[index];
setTokenValue(parent, result, settings);
}
} else if (value1.tokvalue->str() == "{") {
MathLib::bigint index = value2.intvalue;
const Token *element = value1.tokvalue->next();
while (index > 0 && element->str() != "}") {
if (element->str() == ",")
--index;
if (Token::Match(element, "[{}()[]]"))
break;
element = element->next();
}
if (Token::Match(element, "%num% [,}]")) {
result.intvalue = MathLib::toLongNumber(element->str());
setTokenValue(parent, result, settings);
}
}
}
}
}
}
else if (Token::Match(parent, ":: %name%") && parent->astOperand2() == tok) {
setTokenValue(parent, value, settings);
}
@ -1405,6 +1358,67 @@ static void valueFlowArrayBool(TokenList *tokenlist)
}
}
static void valueFlowArrayElement(TokenList* tokenlist, const Settings* settings)
{
for (Token* tok = tokenlist->front(); tok; tok = tok->next()) {
if (!Token::simpleMatch(tok, "["))
continue;
if (!tok->isBinaryOp())
continue;
if (tok->hasKnownIntValue())
continue;
const Token* indexTok = tok->astOperand2();
const Token* arrayTok = tok->astOperand1();
for (const ValueFlow::Value& arrayValue : arrayTok->values()) {
if (!arrayValue.isTokValue())
continue;
for (const ValueFlow::Value& indexValue : indexTok->values()) {
if (!indexValue.isIntValue())
continue;
if (arrayValue.varId != 0 && indexValue.varId != 0 &&
!(arrayValue.varId == indexValue.varId && arrayValue.varvalue == indexValue.varvalue))
continue;
ValueFlow::Value result(0);
result.condition = arrayValue.condition ? arrayValue.condition : indexValue.condition;
result.setInconclusive(arrayValue.isInconclusive() | indexValue.isInconclusive());
result.varId = (arrayValue.varId != 0) ? arrayValue.varId : indexValue.varId;
result.varvalue = (result.varId == arrayValue.varId) ? arrayValue.intvalue : indexValue.intvalue;
if (arrayValue.valueKind == indexValue.valueKind)
result.valueKind = arrayValue.valueKind;
result.errorPath.insert(result.errorPath.end(), arrayValue.errorPath.begin(), arrayValue.errorPath.end());
result.errorPath.insert(result.errorPath.end(), indexValue.errorPath.begin(), indexValue.errorPath.end());
const MathLib::bigint index = indexValue.intvalue;
if (arrayValue.tokvalue->tokType() == Token::eString) {
const std::string s = arrayValue.tokvalue->strValue();
if (index == s.size()) {
result.intvalue = 0;
setTokenValue(tok, result, settings);
} else if (index >= 0 && index < s.size()) {
result.intvalue = s[index];
setTokenValue(tok, result, settings);
}
} else if (Token::simpleMatch(arrayValue.tokvalue, "{")) {
std::vector<const Token*> args = getArguments(arrayValue.tokvalue);
if (index < 0 || index >= args.size())
continue;
const Token* arg = args[index];
if (!arg->hasKnownIntValue())
continue;
const ValueFlow::Value& v = arg->values().front();
result.intvalue = v.intvalue;
result.errorPath.insert(result.errorPath.end(), v.errorPath.begin(), v.errorPath.end());
setTokenValue(tok, result, settings);
}
}
}
}
}
static void valueFlowPointerAlias(TokenList *tokenlist)
{
for (Token *tok = tokenlist->front(); tok; tok = tok->next()) {
@ -8494,6 +8508,7 @@ void ValueFlow::setValues(TokenList *tokenlist, SymbolDatabase* symboldatabase,
valueFlowCondition(SymbolicConditionHandler{}, tokenlist, symboldatabase, errorLogger, settings);
valueFlowSymbolicInfer(tokenlist, symboldatabase);
valueFlowArrayBool(tokenlist);
valueFlowArrayElement(tokenlist, settings);
valueFlowRightShift(tokenlist, settings);
valueFlowAfterAssign(tokenlist, symboldatabase, errorLogger, settings);
valueFlowAfterSwap(tokenlist, symboldatabase, errorLogger, settings);

14
test/testvalueflow.cpp
View File

@ -754,6 +754,20 @@ private:
" return x[0];\n"
"}";
ASSERT_EQUALS(0, valueOfTok(code, "[").intvalue);
code = "int g() { return 3; }\n"
"void f() {\n"
" const int x[2] = { g(), g() };\n"
" return x[0];\n"
"}\n";
ASSERT_EQUALS(3, valueOfTok(code, "[ 0").intvalue);
code = "int g() { return 3; }\n"
"void f() {\n"
" const int x[2] = { g(), g() };\n"
" return x[1];\n"
"}\n";
ASSERT_EQUALS(3, valueOfTok(code, "[ 1").intvalue);
}
void valueFlowMove() {