simplifyCondition: handle also '( a || true || b)' -> '(true)' and '( a && false && b)' -> '(false)'.

Clarify a comment about previous commit.

lib/tokenize.cpp

@@ -3955,7 +3955,7 @@ bool Tokenizer::removeRedundantConditions()
         if (Token::simpleMatch(elseTag, "else {")) {
             // Handle else
             if (boolValue == false) {
-                // Convert "if( false ) {aaa;} else {bbb;}" => "{bbb;}" or ";{bbb;}"
+                // Convert "if( false ) {aaa;} else {bbb;}" => "{bbb;}"
 
                 //remove '(false)'
                 tok->deleteNext(3);
@@ -4508,6 +4508,30 @@ bool Tokenizer::simplifyConditions()
             ret = true;
         }
 
+        else if (Token::simpleMatch(tok, "&& false &&") ||
+                 Token::simpleMatch(tok, "|| true ||")) {
+            //goto '('
+            Token *tok2 = tok;
+            while (tok2->previous()) {
+                if (tok2->previous()->str() == ")")
+                    tok2 = tok2->previous()->link();
+                else {
+                    tok2 = tok2->previous();
+                    if (tok2->str() == "(")
+                        break;
+                }
+            }
+            if (!tok2)
+                continue;
+            //move tok to 'true|false' position
+            tok = tok->next();
+            //remove everything before 'true|false'
+            Token::eraseTokens(tok2, tok);
+            //remove everything after 'true|false'
+            Token::eraseTokens(tok, tok2->link());
+            ret = true;
+        }
+
         // Change numeric constant in condition to "true" or "false"
         if (Token::Match(tok, "if|while ( %num% )|%oror%|&&")) {
             tok->tokAt(2)->str((tok->strAt(2) != "0") ? "true" : "false");

test/testsimplifytokens.cpp

@@ -6359,6 +6359,42 @@ private:
                 "}";
             ASSERT_EQUALS("void f ( int a ) { g ( ) ; }", tok(code));
         }
+
+        {
+            const char code[] =
+                "void f(int a)\n"
+                "{\n"
+                "if (a || true || b) g();\n"
+                "}";
+            ASSERT_EQUALS("void f ( int a ) { g ( ) ; }", tok(code));
+        }
+
+        {
+            const char code[] =
+                "void f(int a)\n"
+                "{\n"
+                "if (a && false && b) g();\n"
+                "}";
+            ASSERT_EQUALS("void f ( int a ) { }", tok(code));
+        }
+
+        {
+            const char code[] =
+                "void f(int a)\n"
+                "{\n"
+                "if (a || (b && false && c) || d) g();\n"
+                "}";
+            ASSERT_EQUALS("void f ( int a ) { if ( a || d ) { g ( ) ; } }", tok(code));
+        }
+
+        {
+            const char code[] =
+                "void f(int a)\n"
+                "{\n"
+                "if ((a && b) || true || (c && d)) g();\n"
+                "}";
+            ASSERT_EQUALS("void f ( int a ) { g ( ) ; }", tok(code));
+        }
     }