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Merged
danmar merged 13 commits into from
Jan 10, 2021
Merged

Fix issue 8871: improve check: mismatching container size conditions #2988

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e4c538c
Fix issue 8871: improve check: mismatching container size conditions
pfultz2 Dec 24, 2020
6ab32a5
Reuse calculate function
pfultz2 Dec 25, 2020
2a05480
Remove unused code
pfultz2 Dec 26, 2020
ce28b8e
Formatting
pfultz2 Dec 26, 2020
74078a8
Use encodeMultiChar
pfultz2 Dec 28, 2020
2c9d799
Remove header
pfultz2 Dec 28, 2020
a520e98
Throw internal error instead
pfultz2 Dec 28, 2020
4539fe2
Merge branch 'main' into valueflow-container-ops
pfultz2 Dec 30, 2020
9069fdc
Merge
pfultz2 Jan 9, 2021
5cfeb20
Remove useless branch
pfultz2 Jan 9, 2021
6d11171
Dont warn on simple functions that always return true or false
pfultz2 Jan 9, 2021
afc27b5
Fix negative index
pfultz2 Jan 9, 2021
3d218b6
Use std::max instead
pfultz2 Jan 9, 2021
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7 changes: 6 additions & 1 deletion lib/checkcondition.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -1385,10 +1385,15 @@ void CheckCondition::alwaysTrueFalse()
const SymbolDatabase *symbolDatabase = mTokenizer->getSymbolDatabase();
for (const Scope * scope : symbolDatabase->functionScopes) {
for (const Token* tok = scope->bodyStart->next(); tok != scope->bodyEnd; tok = tok->next()) {
if (tok->link()) // don't write false positives when templates are used
if (Token::simpleMatch(tok, "<") && tok->link()) // don't write false positives when templates are used
continue;
if (!tok->hasKnownIntValue())
continue;
if (Token::Match(tok->previous(), "%name% (") && tok->previous()->function()) {
const Function* f = tok->previous()->function();
if (f->functionScope && Token::Match(f->functionScope->bodyStart, "{ return true|false ;"))
continue;
}
{
// is this a condition..
const Token *parent = tok->astParent();
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8 changes: 0 additions & 8 deletions lib/checkuninitvar.cpp
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Expand Up @@ -266,14 +266,6 @@ static void conditionAlwaysTrueOrFalse(const Token *tok, const std::map<int, Var
}

else if (tok->isComparisonOp()) {
if (tok->hasKnownIntValue()) {
if (tok->values().front().intvalue)
*alwaysTrue = true;
else
*alwaysFalse = true;
return;
}

if (variableValue.empty()) {
return;
}
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2 changes: 1 addition & 1 deletion lib/clangimport.cpp
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Expand Up @@ -390,7 +390,7 @@ std::string clangimport::AstNode::getSpelling() const
while (typeIndex > 0 && std::isalpha(mExtTokens[typeIndex][0]))
typeIndex--;
}
const std::string &str = mExtTokens[typeIndex - 1];
const std::string &str = mExtTokens[std::max(typeIndex - 1, 0)];
if (str.compare(0,4,"col:") == 0)
return "";
if (str.compare(0,8,"<invalid") == 0)
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2 changes: 1 addition & 1 deletion lib/mathlib.cpp
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Expand Up @@ -346,7 +346,7 @@ MathLib::biguint MathLib::toULongNumber(const std::string & str)
return ret;
}

static unsigned int encodeMultiChar(const std::string& str)
unsigned int MathLib::encodeMultiChar(const std::string& str)
{
unsigned int retval = 0;
for (char it : str) {
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2 changes: 2 additions & 0 deletions lib/mathlib.h
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Expand Up @@ -125,6 +125,8 @@ class CPPCHECKLIB MathLib {
*/
static bool isOctalDigit(char c);

static unsigned int encodeMultiChar(const std::string& str);

/**
* \param[in] str character literal
* @return Number of internal representation of the character literal
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242 changes: 104 additions & 138 deletions lib/valueflow.cpp
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Expand Up @@ -80,6 +80,7 @@
#include "analyzer.h"
#include "astutils.h"
#include "errorlogger.h"
#include "errortypes.h"
#include "forwardanalyzer.h"
#include "library.h"
#include "mathlib.h"
Expand All @@ -106,6 +107,7 @@
#include <map>
#include <set>
#include <stack>
#include <stdexcept>
#include <string>
#include <tuple>
#include <vector>
Expand Down Expand Up @@ -341,6 +343,60 @@ static bool isComputableValue(const Token* parent, const ValueFlow::Value& value
return true;
}

template <class T>
T asInt(T x)
{
return x;
}

MathLib::bigint asInt(float x) { return x; }

MathLib::bigint asInt(double x) { return x; }

template <class T, class U>
static T calculate(const std::string& s, T x, U y)

@danmar danmar Dec 27, 2020

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👍 I think a calculate function is a good idea.

{
switch (MathLib::encodeMultiChar(s)) {
case '+':
return x + y;
case '-':
return x - y;
case '*':
return x * y;
case '/':
return x / y;
case '%':
return asInt(x) % asInt(y);
case '&':
return asInt(x) & asInt(y);
case '|':
return asInt(x) | asInt(y);
case '^':
return asInt(x) ^ asInt(y);
case '>':
return x > y;
case '<':
return x < y;
case '<<':
return asInt(x) << asInt(y);
case '>>':
return asInt(x) >> asInt(y);
case '&&':
return x && y;
case '||':
return x || y;
case '==':
return x == y;
case '!=':
return x != y;
case '>=':
return x >= y;
case '<=':
return x <= y;
}
throw InternalError(nullptr, "Unknown operator: " + s);
}

/** Set token value for cast */
static void setTokenValueCast(Token *parent, const ValueType &valueType, const ValueFlow::Value &value, const Settings *settings);

Expand All @@ -359,31 +415,40 @@ static void setTokenValue(Token* tok, const ValueFlow::Value &value, const Setti

if (value.isContainerSizeValue()) {
// .empty, .size, +"abc", +'a'
if (parent->str() == "+" && parent->astOperand1() && parent->astOperand2()) {
if (Token::Match(parent, "+|==|!=") && parent->astOperand1() && parent->astOperand2()) {
for (const ValueFlow::Value &value1 : parent->astOperand1()->values()) {
for (const ValueFlow::Value &value2 : parent->astOperand2()->values()) {
if (value1.path != value2.path)
continue;
ValueFlow::Value result;
result.valueType = ValueFlow::Value::ValueType::CONTAINER_SIZE;
if (Token::Match(parent, "%comp%"))
result.valueType = ValueFlow::Value::ValueType::INT;
else
result.valueType = ValueFlow::Value::ValueType::CONTAINER_SIZE;

if (value1.isContainerSizeValue() && value2.isContainerSizeValue())
result.intvalue = value1.intvalue + value2.intvalue;
result.intvalue = calculate(parent->str(), value1.intvalue, value2.intvalue);
else if (value1.isContainerSizeValue() && value2.isTokValue() && value2.tokvalue->tokType() == Token::eString)
result.intvalue = value1.intvalue + Token::getStrLength(value2.tokvalue);
result.intvalue = calculate(parent->str(), value1.intvalue, Token::getStrLength(value2.tokvalue));
else if (value2.isContainerSizeValue() && value1.isTokValue() && value1.tokvalue->tokType() == Token::eString)
result.intvalue = Token::getStrLength(value1.tokvalue) + value2.intvalue;
result.intvalue = calculate(parent->str(), Token::getStrLength(value1.tokvalue), value2.intvalue);
else
continue;

combineValueProperties(value1, value2, &result);

if (Token::simpleMatch(parent, "==") && result.intvalue)
continue;
if (Token::simpleMatch(parent, "!=") && !result.intvalue)
continue;

setTokenValue(parent, result, settings);
}
}
}


else if (Token::Match(parent, ". %name% (") && parent->astParent() == parent->tokAt(2) && parent->astOperand1() && parent->astOperand1()->valueType()) {
else if (Token::Match(parent, ". %name% (") && parent->astParent() == parent->tokAt(2) &&
parent->astOperand1() && parent->astOperand1()->valueType()) {
const Library::Container *c = parent->astOperand1()->valueType()->container;
const Library::Container::Yield yields = c ? c->getYield(parent->strAt(1)) : Library::Container::Yield::NO_YIELD;
if (yields == Library::Container::Yield::SIZE) {
Expand Down Expand Up @@ -545,147 +610,48 @@ static void setTokenValue(Token* tok, const ValueFlow::Value &value, const Setti
combineValueProperties(value1, value2, &result);
const double floatValue1 = value1.isIntValue() ? value1.intvalue : value1.floatValue;
const double floatValue2 = value2.isIntValue() ? value2.intvalue : value2.floatValue;
switch (parent->str()[0]) {
case '+':
if (value1.isTokValue() || value2.isTokValue())
break;
if (value1.isFloatValue() || value2.isFloatValue()) {
result.valueType = ValueFlow::Value::ValueType::FLOAT;
result.floatValue = floatValue1 + floatValue2;
const bool isFloat = value1.isFloatValue() || value2.isFloatValue();
if (isFloat && Token::Match(parent, "&|^|%|<<|>>|%or%"))
continue;
if (Token::Match(parent, "<<|>>") &&
!(value1.intvalue >= 0 && value2.intvalue >= 0 && value2.intvalue < MathLib::bigint_bits))
continue;
if (Token::Match(parent, "/|%") && floatValue2 == 0)
continue;
if (Token::Match(parent, "==|!=")) {
if ((value1.isIntValue() && value2.isTokValue()) || (value1.isTokValue() && value2.isIntValue())) {
if (parent->str() == "==")
result.intvalue = 0;
else if (parent->str() == "!=")
result.intvalue = 1;
} else if (value1.isIntValue() && value2.isIntValue()) {
result.intvalue = calculate(parent->str(), value1.intvalue, value2.intvalue);
} else {
result.intvalue = value1.intvalue + value2.intvalue;
continue;
}
setTokenValue(parent, result, settings);
break;
case '-':
if (value1.isTokValue() || value2.isTokValue())
break;
if (value1.isFloatValue() || value2.isFloatValue()) {
result.valueType = ValueFlow::Value::ValueType::FLOAT;
result.floatValue = floatValue1 - floatValue2;
} else {
// Avoid overflow
if (value1.intvalue < 0 && value2.intvalue > value1.intvalue - LLONG_MIN)
break;

result.intvalue = value1.intvalue - value2.intvalue;
}
// If the bound comes from the second value then invert the bound
if (value2.bound == result.bound && value2.bound != ValueFlow::Value::Bound::Point)
result.invertBound();
} else if (Token::Match(parent, "%comp%")) {
if (!isFloat && !value1.isIntValue() && !value2.isIntValue())
continue;
if (isFloat)
result.intvalue = calculate(parent->str(), floatValue1, floatValue2);
else
result.intvalue = calculate(parent->str(), value1.intvalue, value2.intvalue);
setTokenValue(parent, result, settings);
break;
case '*':
} else if (Token::Match(parent, "%op%")) {
if (value1.isTokValue() || value2.isTokValue())
break;
if (value1.isFloatValue() || value2.isFloatValue()) {
result.valueType = ValueFlow::Value::ValueType::FLOAT;
result.floatValue = floatValue1 * floatValue2;
} else {
result.intvalue = value1.intvalue * value2.intvalue;
}
setTokenValue(parent, result, settings);
break;
case '/':
if (value1.isTokValue() || value2.isTokValue() || value2.intvalue == 0)
break;
if (value1.isFloatValue() || value2.isFloatValue()) {
if (isFloat) {
result.valueType = ValueFlow::Value::ValueType::FLOAT;
result.floatValue = floatValue1 / floatValue2;
result.floatValue = calculate(parent->str(), floatValue1, floatValue2);
} else {
result.intvalue = value1.intvalue / value2.intvalue;
result.intvalue = calculate(parent->str(), value1.intvalue, value2.intvalue);
}
// If the bound comes from the second value then invert the bound when subtracting
if (Token::simpleMatch(parent, "-") && value2.bound == result.bound &&
value2.bound != ValueFlow::Value::Bound::Point)
result.invertBound();
setTokenValue(parent, result, settings);
break;
case '%':
if (!value1.isIntValue() || !value2.isIntValue())
break;
if (value2.intvalue == 0)
break;
result.intvalue = value1.intvalue % value2.intvalue;
setTokenValue(parent, result, settings);
break;
case '=':
if (parent->str() == "==") {
if ((value1.isIntValue() && value2.isTokValue()) ||
(value1.isTokValue() && value2.isIntValue())) {
result.intvalue = 0;
setTokenValue(parent, result, settings);
} else if (value1.isIntValue() && value2.isIntValue()) {
result.intvalue = value1.intvalue == value2.intvalue;
setTokenValue(parent, result, settings);
}
}
break;
case '!':
if (parent->str() == "!=") {
if ((value1.isIntValue() && value2.isTokValue()) ||
(value1.isTokValue() && value2.isIntValue())) {
result.intvalue = 1;
setTokenValue(parent, result, settings);
} else if (value1.isIntValue() && value2.isIntValue()) {
result.intvalue = value1.intvalue != value2.intvalue;
setTokenValue(parent, result, settings);
}
}
break;
case '>': {
const bool f = value1.isFloatValue() || value2.isFloatValue();
if (!f && !value1.isIntValue() && !value2.isIntValue())
break;
if (parent->str() == ">")
result.intvalue = f ? (floatValue1 > floatValue2) : (value1.intvalue > value2.intvalue);
else if (parent->str() == ">=")
result.intvalue = f ? (floatValue1 >= floatValue2) : (value1.intvalue >= value2.intvalue);
else if (!f && parent->str() == ">>" && value1.intvalue >= 0 && value2.intvalue >= 0 && value2.intvalue < MathLib::bigint_bits)
result.intvalue = value1.intvalue >> value2.intvalue;
else
break;
setTokenValue(parent, result, settings);
break;
}
case '<': {
const bool f = value1.isFloatValue() || value2.isFloatValue();
if (!f && !value1.isIntValue() && !value2.isIntValue())
break;
if (parent->str() == "<")
result.intvalue = f ? (floatValue1 < floatValue2) : (value1.intvalue < value2.intvalue);
else if (parent->str() == "<=")
result.intvalue = f ? (floatValue1 <= floatValue2) : (value1.intvalue <= value2.intvalue);
else if (!f && parent->str() == "<<" && value1.intvalue >= 0 && value2.intvalue >= 0 && value2.intvalue < MathLib::bigint_bits)
result.intvalue = value1.intvalue << value2.intvalue;
else
break;
setTokenValue(parent, result, settings);
break;
}
case '&':
if (!value1.isIntValue() || !value2.isIntValue())
break;
if (parent->str() == "&")
result.intvalue = value1.intvalue & value2.intvalue;
else
result.intvalue = value1.intvalue && value2.intvalue;
setTokenValue(parent, result, settings);
break;
case '|':
if (!value1.isIntValue() || !value2.isIntValue())
break;
if (parent->str() == "|")
result.intvalue = value1.intvalue | value2.intvalue;
else
result.intvalue = value1.intvalue || value2.intvalue;
setTokenValue(parent, result, settings);
break;
case '^':
if (!value1.isIntValue() || !value2.isIntValue())
break;
result.intvalue = value1.intvalue ^ value2.intvalue;
setTokenValue(parent, result, settings);
break;
default:
// unhandled operator, do nothing
break;
}
}
}
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