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ValueFlow: Improved when using '[' on arrays and strings

This commit is contained in:
Daniel Marjamäki 2015-02-24 15:57:39 +01:00
parent 8427398d9d
commit d1892786b8
2 changed files with 88 additions and 11 deletions
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80
lib/valueflow.cpp
View File

@ -317,14 +317,16 @@ static void setTokenValue(Token* tok, const ValueFlow::Value &value)
}
Token *parent = const_cast<Token*>(tok->astParent());
if (!parent)
return;
// Cast..
if (parent && parent->str() == "(" && tok == parent->link()->next()) {
if (parent->str() == "(" && tok == parent->link()->next()) {
setTokenValue(parent,value);
}
// Calculations..
else if (parent && parent->isArithmeticalOp() && parent->astOperand1() && parent->astOperand2()) {
else if (parent->isArithmeticalOp() && parent->astOperand1() && parent->astOperand2()) {
std::list<ValueFlow::Value>::const_iterator value1, value2;
for (value1 = parent->astOperand1()->values.begin(); value1 != parent->astOperand1()->values.end(); ++value1) {
for (value2 = parent->astOperand2()->values.begin(); value2 != parent->astOperand2()->values.end(); ++value2) {
@ -365,6 +367,49 @@ static void setTokenValue(Token* tok, const ValueFlow::Value &value)
}
}
}
// Array element
else if (parent->str() == "[" && parent->astOperand1() && parent->astOperand2()) {
std::list<ValueFlow::Value>::const_iterator value1, value2;
for (value1 = parent->astOperand1()->values.begin(); value1 != parent->astOperand1()->values.end(); ++value1) {
if (!value1->tokvalue)
continue;
for (value2 = parent->astOperand2()->values.begin(); value2 != parent->astOperand2()->values.end(); ++value2) {
if (value2->tokvalue)
continue;
if (value1->varId == 0U || value2->varId == 0U ||
(value1->varId == value2->varId && value1->varvalue == value2->varvalue)) {
ValueFlow::Value result(0);
result.condition = value1->condition ? value1->condition : value2->condition;
result.inconclusive = value1->inconclusive | value2->inconclusive;
result.varId = (value1->varId != 0U) ? value1->varId : value2->varId;
result.varvalue = (result.varId == value1->varId) ? value1->intvalue : value2->intvalue;
if (value1->tokvalue->type() == Token::eString) {
const std::string s = value1->tokvalue->strValue();
const MathLib::bigint index = value2->intvalue;
if (index >= 0 && index < s.size()) {
result.intvalue = s[index];
setTokenValue(parent, result);
}
} 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);
}
}
}
}
}
}
}
static void valueFlowNumber(TokenList *tokenlist)
@ -377,28 +422,40 @@ static void valueFlowNumber(TokenList *tokenlist)
static void valueFlowString(TokenList *tokenlist)
{
std::map<unsigned int, const Token *> constantStrings;
for (Token *tok = tokenlist->front(); tok; tok = tok->next()) {
if (tok->type() == Token::eString) {
ValueFlow::Value strvalue;
strvalue.tokvalue = tok;
setTokenValue(tok, strvalue);
}
}
}
static void valueFlowArray(TokenList *tokenlist)
{
std::map<unsigned int, const Token *> constantArrays;
for (Token *tok = tokenlist->front(); tok; tok = tok->next()) {
if (Token::Match(tok, "const %type% %var% [ %num%| ] = {")) {
const Token *vartok = tok->tokAt(2);
const Token *rhstok = vartok->next()->link()->tokAt(2);
constantArrays[vartok->varId()] = rhstok;
tok = rhstok->link();
}
if (Token::Match(tok, "const char %var% [ %num%| ] = %str% ;")) {
const Token *vartok = tok->tokAt(2);
const Token *strtok = vartok->next()->link()->tokAt(2);
constantStrings[vartok->varId()] = strtok;
tok = vartok->next();
constantArrays[vartok->varId()] = strtok;
tok = strtok->next();
}
if (tok->varId() > 0U) {
const std::map<unsigned int, const Token *>::const_iterator it = constantStrings.find(tok->varId());
if (it != constantStrings.end()) {
ValueFlow::Value strvalue;
strvalue.tokvalue = it->second;
setTokenValue(tok, strvalue);
const std::map<unsigned int, const Token *>::const_iterator it = constantArrays.find(tok->varId());
if (it != constantArrays.end()) {
ValueFlow::Value value;
value.tokvalue = it->second;
setTokenValue(tok, value);
}
}
}
@ -1781,6 +1838,7 @@ void ValueFlow::setValues(TokenList *tokenlist, SymbolDatabase* symboldatabase,
valueFlowNumber(tokenlist);
valueFlowString(tokenlist);
valueFlowArray(tokenlist);
valueFlowPointerAlias(tokenlist);
valueFlowFunctionReturn(tokenlist, errorLogger, settings);
valueFlowBitAnd(tokenlist);

19
test/testvalueflow.cpp
View File

@ -37,6 +37,7 @@ private:
TEST_CASE(valueFlowNumber);
TEST_CASE(valueFlowString);
TEST_CASE(valueFlowPointerAlias);
TEST_CASE(valueFlowArrayElement);
TEST_CASE(valueFlowBitAnd);
@ -198,6 +199,24 @@ private:
ASSERT_EQUALS(true, testValueOfX(code, 4, "& i"));
}
void valueFlowArrayElement() {
const char *code;
code = "void f() {\n"
" const int a[] = {43,23,12};\n"
" int x = a[0];\n"
" return x;\n"
"}";
ASSERT_EQUALS(true, testValueOfX(code, 4U, 43));
code = "void f() {\n"
" const char abcd[] = \"abcd\";\n"
" int x = abcd[2];\n"
" return x;\n"
"}";
ASSERT_EQUALS(true, testValueOfX(code, 4U, 'c'));
}
void valueFlowCalculations() {
const char *code;
/*