walkero
/
cppcheck
1
0
Fork 0
Code Issues Pull Requests Projects Releases 1 Wiki Activity

value flow: better handling of conditional code below || && ?: operators

This commit is contained in:
Daniel Marjamäki 2014-01-19 09:05:48 +01:00
parent 2d0a68cac2
commit cdaa7abf7e
2 changed files with 42 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

34
lib/valueflow.cpp
View File

@ -25,6 +25,7 @@
#include "tokenlist.h" #include "tokenlist.h"
#include <iostream> #include <iostream>
#include <stack>
static void printvalues(const Token *tok) static void printvalues(const Token *tok)
@ -84,14 +85,35 @@ static bool bailoutFunctionPar(const Token *tok, const ValueFlow::Value &value,
return arg && !arg->isConst() && arg->isReference(); return arg && !arg->isConst() && arg->isReference();
} }
static const Token * skipValueInConditionalExpression(const Token *tok) /**
* Should value be skipped because it's hidden inside && || or ?: expression.
* Example: ((x!=NULL) && (*x == 123))
* If 'valuetok' points at the x in '(*x == 123)'. Then the '&&' will be returned.
* @param valuetok original variable token
* @return NULL=>don't skip, non-NULL=>The operator token that cause the skip. For instance the '&&'.
* */
static const Token * skipValueInConditionalExpression(const Token * const valuetok)
{ {
while (tok && !Token::Match(tok, "%oror%|&&|?|:")) { // Walk up the ast
while (Token::Match(tok->astParent(), "%oror%|&&|?") && tok->astParent()->astOperand1() == tok) for (const Token *tok = valuetok->astParent(); tok; tok = tok->astParent()) {
tok = tok->astParent(); if (!Token::Match(tok, "%oror%|&&|?|:"))
tok = tok->astParent(); continue;
// Is variable protected in LHS..
std::stack<const Token *> tokens;
tokens.push(tok->astOperand1());
while (!tokens.empty()) {
const Token * const tok2 = tokens.top();
tokens.pop();
if (!tok2)
continue;
if (tok2 != valuetok && tok2->str() == valuetok->str())
return tok;
tokens.push(tok2->astOperand2());
tokens.push(tok2->astOperand1());
}
} }
return tok; return NULL;
} }
static bool bailoutSelfAssignment(const Token * const tok) static bool bailoutSelfAssignment(const Token * const tok)

14
test/testvalueflow.cpp
View File

@ -340,6 +340,20 @@ private:
} }
void valueFlowBeforeConditionIfElse() { // bailout: if/else/etc void valueFlowBeforeConditionIfElse() { // bailout: if/else/etc
const char *code;
code = "void f(X * x) {\n"
" a = x;\n"
" if ((x != NULL) &&\n"
" (a(x->name, html)) &&\n"
" (a(x->name, body))) {}\n"
" if (x != NULL) { }\n"
"}";
ASSERT_EQUALS(true, testValueOfX(code, 2U, 0));
TODO_ASSERT_EQUALS(true, false, testValueOfX(code, 3U, 0));
ASSERT_EQUALS(false, testValueOfX(code, 3U, 0));
ASSERT_EQUALS(false, testValueOfX(code, 3U, 0));
bailout("void f(int x) {\n" bailout("void f(int x) {\n"
" if (x != 123) { b = x; }\n" " if (x != 123) { b = x; }\n"
" if (x == 123) {}\n" " if (x == 123) {}\n"