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Simplification of p = realloc(NULL, n) as p = malloc (n) #6

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Merged
2 commits merged into from
Jan 4, 2011
Merged

Simplification of p = realloc(NULL, n) as p = malloc (n) #6

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e75a816
Move simplification of realloc after simplification of math ops
rgeissert Jan 2, 2011
3d9550b
Simplify "x = realloc (0, n);" to "x = malloc(n);"
rgeissert Jan 2, 2011
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73 changes: 43 additions & 30 deletions lib/tokenize.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -4076,36 +4076,6 @@ bool Tokenizer::simplifyTokenList()

simplifyCasts();

// simplify "x=realloc(y,0);" => "free(y); x=0;"..
for (Token *tok = _tokens; tok; tok = tok->next())
{
if (Token::Match(tok, "; %var% = realloc ( %var% , 0 ) ;"))
{
const std::string varname(tok->next()->str());
const unsigned int varid(tok->next()->varId());

// Delete the "%var% ="
tok->deleteNext();
tok->deleteNext();

// Change function name "realloc" to "free"
tok->next()->str("free");

// delete the ", 0"
Token::eraseTokens(tok->tokAt(3), tok->tokAt(6));

// goto the ";"
tok = tok->tokAt(5);

// insert "var=0;"
tok->insertToken(";");
tok->insertToken("0");
tok->insertToken("=");
tok->insertToken(varname);
tok->next()->varId(varid);
}
}

// Simplify simple calculations..
simplifyCalculations();

Expand Down Expand Up @@ -4145,6 +4115,49 @@ bool Tokenizer::simplifyTokenList()
}
}

// simplify "x=realloc(y,0);" => "free(y); x=0;"..
// and "x = realloc (0, n);" => "x = malloc(n);"
for (Token *tok = _tokens; tok; tok = tok->next())
{
if (Token::Match(tok, "; %var% = realloc ( %var% , 0 ) ;"))
{
const std::string varname(tok->next()->str());
const unsigned int varid(tok->next()->varId());

// Delete the "%var% ="
tok->deleteNext();
tok->deleteNext();

// Change function name "realloc" to "free"
tok->next()->str("free");

// delete the ", 0"
Token::eraseTokens(tok->tokAt(3), tok->tokAt(6));

// goto the ";"
tok = tok->tokAt(5);

// insert "var=0;"
tok->insertToken(";");
tok->insertToken("0");
tok->insertToken("=");
tok->insertToken(varname);
tok->next()->varId(varid);
}
else if (Token::Match(tok, "; %var% = realloc ( 0 , %num% ) ;"))
{
const std::string varname(tok->next()->str());

tok = tok->tokAt(3);
// Change function name "realloc" to "malloc"
tok->str("malloc");

// delete "0 ,"
tok->next()->deleteNext();
tok->next()->deleteNext();
}
}

// Change initialisation of variable to assignment
simplifyInitVar();

Expand Down
4 changes: 4 additions & 0 deletions test/testsimplifytokens.cpp
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Expand Up @@ -6004,6 +6004,10 @@ class TestSimplifyTokens : public TestFixture
{
ASSERT_EQUALS("; free ( p ) ; p = 0 ;",
tok("; p = realloc(p,0);"));
ASSERT_EQUALS("; p = malloc ( 100 ) ;",
tok("; p = realloc(0, 100);"));
ASSERT_EQUALS("; p = malloc ( 0 ) ;",
tok("; p = realloc(0, sizeof(char)*0);"));
}

void simplifyErrNoInWhile()
Expand Down