Tokenizer: extract realloc simplification and simplify also when each argument is done by more than one token.

Restyling of a comment in tokenize.h.

lib/tokenize.cpp

@@ -3681,41 +3681,7 @@ 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(2);
-
-            // Change function name "realloc" to "free"
-            tok->next()->str("free");
-
-            // delete the ", 0"
-            tok = tok->tokAt(3);
-            tok->deleteNext(2);
-
-            // goto the ";"
-            tok = tok->tokAt(2);
-
-            // 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% ) ;")) {
-            tok = tok->tokAt(3);
-            // Change function name "realloc" to "malloc"
-            tok->str("malloc");
-
-            // delete "0 ,"
-            tok->next()->deleteNext(2);
-        }
-    }
+    simplifyRealloc();
 
     // Change initialisation of variable to assignment
     simplifyInitVar();
@@ -3880,6 +3846,51 @@ void Tokenizer::removeRedundantAssignment()
     }
 }
 
+void Tokenizer::simplifyRealloc()
+{
+    for (Token *tok = _tokens; tok; tok = tok->next()) {
+        if (tok->str() == "(" || tok->str() == "[" ||
+            (tok->str() == "{" && tok->previous() && tok->previous()->str() == "="))
+            tok = tok->link();
+        else if (Token::Match(tok, "[;{}] %var% = realloc (")) {
+            tok = tok->tokAt(3);
+            if (Token::Match(tok->next(), "( 0 ,")) {
+                //no "x = realloc(0,);"
+                if (!Token::Match(tok->next()->link(), ") ;") || tok->next()->link()->previous() == tok->tokAt(3))
+                    continue;
+
+                // delete "0 ,"
+                tok->next()->deleteNext(2);
+
+                // Change function name "realloc" to "malloc"
+                tok->str("malloc");
+                tok = tok->next()->link();
+            } else {
+                Token *tok2 = tok->next()->link()->tokAt(-2);
+                //no "x = realloc(,0);"
+                if (!Token::simpleMatch(tok2, ", 0 ) ;") || tok2 == tok->tokAt(2))
+                    continue;
+
+                //remove ", 0"
+                tok2 = tok2->previous();
+                tok2->deleteNext(2);
+                //change "realloc" to "free"
+                tok->str("free");
+                //insert "0" after "var ="
+                tok = tok->previous();
+                tok->insertToken("0");
+                //move "var = 0" between "free(...)" and ";"
+                tok2 = tok2->next();
+                Token::move(tok->previous(), tok->next(), tok2);
+                //add missing ";" after "free(...)"
+                tok2->insertToken(";");
+                //goto before last ";" and continue
+                tok = tok->next();
+            }
+        }
+    }
+}
+
 void Tokenizer::simplifyFlowControl()
 {
     unsigned int indentlevel = 0;

lib/tokenize.h

@@ -232,6 +232,12 @@ public:
     /** Remove redundant assignment */
     void removeRedundantAssignment();
 
+    /** Simplifies some realloc usage like
+      * 'x = realloc (0, n);' => 'x = malloc(n);'
+      * 'x = realloc (y, 0);' => 'x = 0; free(y);'
+      */
+    void simplifyRealloc();
+
     /**
      * Replace sizeof() to appropriate size.
      */
@@ -245,9 +251,7 @@ public:
 
     /**
      * Simplify variable initialization
-     * ; int *p(0);
-     * =>
-     * ; int *p = 0;
+     * '; int *p(0);' => '; int *p = 0;'
      */
     void simplifyInitVar();
     Token * initVar(Token * tok);

test/testsimplifytokens.cpp

@@ -7001,12 +7001,14 @@ private:
     }
 
     void simplifyRealloc() {
-        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);"));
+        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, 0);"));
+        ASSERT_EQUALS("; free ( q ) ; p = 0 ;", tok("; p = realloc(q, 0);"));
+        ASSERT_EQUALS("; free ( * q ) ; p = 0 ;", tok("; p = realloc(*q, 0);"));
+        ASSERT_EQUALS("; free ( f ( z ) ) ; p = 0 ;", tok("; p = realloc(f(z), 0);"));
+        ASSERT_EQUALS("; p = malloc ( n * m ) ;", tok("; p = realloc(0, n*m);"));
+        ASSERT_EQUALS("; p = malloc ( f ( 1 ) ) ;", tok("; p = realloc(0, f(1));"));
     }
 
     void simplifyErrNoInWhile() {