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Refactoring FwdAnalysis

This commit is contained in:
Daniel Marjamäki 2018-12-02 17:42:18 +01:00
parent 6734571f06
commit d8fada6702
3 changed files with 32 additions and 26 deletions
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44
lib/astutils.cpp
View File

@ -1053,21 +1053,8 @@ static bool hasFunctionCall(const Token *tok)
return hasFunctionCall(tok->astOperand1()) || hasFunctionCall(tok->astOperand2());
}
FwdAnalysis::Result FwdAnalysis::checkRecursive(const Token *assign1, const Token *startToken, const Token *endToken)
FwdAnalysis::Result FwdAnalysis::checkRecursive(const Token *expr, const Token *startToken, const Token *endToken, const std::set<unsigned int> &exprVarIds, bool local)
{
// all variable ids in assign1 LHS.
std::set<unsigned int> assign1LhsVarIds;
bool local = true;
visitAstNodes(assign1->astOperand1(),
[&](const Token *tok) {
if (tok->varId() > 0) {
assign1LhsVarIds.insert(tok->varId());
if (!Token::simpleMatch(tok->previous(), "."))
local &= !nonLocal(tok->variable());
}
return ChildrenToVisit::op1_and_op2;
});
// Parse the given tokens
for (const Token *tok = startToken; tok != endToken; tok = tok->next()) {
if (Token::simpleMatch(tok, "try {")) {
@ -1101,7 +1088,7 @@ FwdAnalysis::Result FwdAnalysis::checkRecursive(const Token *assign1, const Toke
return Result(Result::Type::BAILOUT);
}
if (assign1LhsVarIds.find(tok->varId()) != assign1LhsVarIds.end()) {
if (exprVarIds.find(tok->varId()) != exprVarIds.end()) {
const Token *parent = tok;
while (Token::Match(parent->astParent(), ".|::|["))
parent = parent->astParent();
@ -1110,10 +1097,10 @@ FwdAnalysis::Result FwdAnalysis::checkRecursive(const Token *assign1, const Toke
// TODO: this is a quick bailout
return Result(Result::Type::BAILOUT);
}
if (hasOperand(parent->astParent()->astOperand2(), assign1->astOperand1())) {
if (hasOperand(parent->astParent()->astOperand2(), expr)) {
return Result(Result::Type::READ);
}
const bool reassign = isSameExpression(mCpp, false, assign1->astOperand1(), parent, mLibrary, false, false, nullptr);
const bool reassign = isSameExpression(mCpp, false, expr, parent, mLibrary, false, false, nullptr);
if (reassign)
return Result(Result::Type::WRITE, parent->astParent());
return Result(Result::Type::READ);
@ -1124,12 +1111,12 @@ FwdAnalysis::Result FwdAnalysis::checkRecursive(const Token *assign1, const Toke
}
if (Token::Match(tok, ") {")) {
const Result &result1 = checkRecursive(assign1, tok->tokAt(2), tok->linkAt(1));
const Result &result1 = checkRecursive(expr, tok->tokAt(2), tok->linkAt(1), exprVarIds, local);
if (result1.type == Result::Type::READ || result1.type == Result::Type::BAILOUT)
return result1;
if (Token::simpleMatch(tok->linkAt(1), "} else {")) {
const Token *elseStart = tok->linkAt(1)->tokAt(2);
const Result &result2 = checkRecursive(assign1, elseStart, elseStart->link());
const Result &result2 = checkRecursive(expr, elseStart, elseStart->link(), exprVarIds, local);
if (result2.type == Result::Type::READ || result2.type == Result::Type::BAILOUT)
return result2;
if (result1.type == Result::Type::WRITE && result2.type == Result::Type::WRITE)
@ -1144,9 +1131,22 @@ FwdAnalysis::Result FwdAnalysis::checkRecursive(const Token *assign1, const Toke
return Result(Result::Type::NONE);
}
FwdAnalysis::Result FwdAnalysis::check(const Token *assign1, const Token *startToken, const Token *endToken)
FwdAnalysis::Result FwdAnalysis::check(const Token *expr, const Token *startToken, const Token *endToken)
{
Result result = checkRecursive(assign1, startToken, endToken);
// all variable ids in expr.
std::set<unsigned int> exprVarIds;
bool local = true;
visitAstNodes(expr,
[&](const Token *tok) {
if (tok->varId() > 0) {
exprVarIds.insert(tok->varId());
if (!Token::simpleMatch(tok->previous(), "."))
local &= !nonLocal(tok->variable());
}
return ChildrenToVisit::op1_and_op2;
});
Result result = checkRecursive(expr, startToken, endToken, exprVarIds, local);
// Break => continue checking in outer scope
while (result.type == FwdAnalysis::Result::Type::BREAK) {
@ -1155,7 +1155,7 @@ FwdAnalysis::Result FwdAnalysis::check(const Token *assign1, const Token *startT
s = s->nestedIn;
if (s->type != Scope::eSwitch)
break;
result = checkRecursive(assign1, s->bodyEnd->next(), endToken);
result = checkRecursive(expr, s->bodyEnd->next(), endToken, exprVarIds, local);
}
return result;

12
lib/astutils.h
View File

@ -172,13 +172,19 @@ public:
const Token *token;
};
/** forward analysis */
struct Result check(const Token *assign1, const Token *startToken, const Token *endToken);
/**
* General purpose forward analysis for "expr". The "expr" can be a tree (x.y[12]) or something like that.
* @param expr Symbolic expression to perform forward analysis for
* @param startToken First token in forward analysis
* @param endToken Last token in forward analysis
* @return A Result struct.
*/
struct Result check(const Token *expr, const Token *startToken, const Token *endToken);
bool hasOperand(const Token *tok, const Token *lhs) const;
private:
struct Result checkRecursive(const Token *assign1, const Token *startToken, const Token *endToken);
struct Result checkRecursive(const Token *expr, const Token *startToken, const Token *endToken, const std::set<unsigned int> &exprVarIds, bool local);
const bool mCpp;
const Library &mLibrary;

2
lib/checkother.cpp
View File

@ -486,7 +486,7 @@ void CheckOther::checkRedundantAssignment()
start = tok->findExpressionStartEndTokens().second->next();
// Get next assignment..
FwdAnalysis::Result nextAssign = fwdAnalysis.check(tok, start, scope->bodyEnd);
FwdAnalysis::Result nextAssign = fwdAnalysis.check(tok->astOperand1(), start, scope->bodyEnd);
if (nextAssign.type != FwdAnalysis::Result::Type::WRITE || !nextAssign.token)
continue;