Fixed #9459 (MISRA Rule 2.2: Find dead code in arithmetic operators)

Author: danmar

addons/misra.py

@@ -1433,6 +1433,23 @@ def misra_1_4(self, cfg):
                                  'wcrtomb_s', 'mbsrtowcs_s', 'wcsrtombs_s'):
                     self.reportError(token, 1, 4)
 
+    def misra_2_2(self, cfg):
+        for token in cfg.tokenlist:
+            if (token.str in '+-') and token.astOperand2:
+                if simpleMatch(token.astOperand1, '0'):
+                    self.reportError(token.astOperand1, 2, 2)
+                elif simpleMatch(token.astOperand2, '0'):
+                    self.reportError(token.astOperand2, 2, 2)
+            if token.str == '*' and token.astOperand2:
+                if simpleMatch(token.astOperand2, '0'):
+                    self.reportError(token.astOperand1, 2, 2)
+                elif simpleMatch(token.astOperand1, '0'):
+                    self.reportError(token.astOperand2, 2, 2)
+                elif simpleMatch(token.astOperand1, '1'):
+                    self.reportError(token.astOperand1, 2, 2)
+                elif simpleMatch(token.astOperand2, '1'):
+                    self.reportError(token.astOperand2, 2, 2)
+
     def misra_2_3(self, dumpfile, typedefInfo):
         self._save_ctu_summary_typedefs(dumpfile, typedefInfo)
 
@@ -4227,6 +4244,7 @@ def fillVerifyExpected(verify_expected, tok):
                 self.printStatus('Checking %s, config %s...' % (dumpfile, cfg.name))
 
             self.executeCheck(104, self.misra_1_4, cfg)
+            self.executeCheck(202, self.misra_2_2, cfg)
             self.executeCheck(203, self.misra_2_3, dumpfile, cfg.typedefInfo)
             self.executeCheck(204, self.misra_2_4, dumpfile, cfg)
             self.executeCheck(205, self.misra_2_5, dumpfile, cfg)

addons/test/misra/misra-test.c

@@ -65,6 +65,16 @@ static _Noreturn void misra_1_4_func(void) // 1.4
     printf_s("hello"); // 1.4
 }
 
+static void misra_2_2(int x) {
+    int a;
+    a = x + 0; // 2.2
+    a = 0 + x; // 2.2
+    a = x * 0; // 2.2
+    a = 0 * x; // 2.2
+    a = x * 1; // 2.2
+    a = 1 * x; // 2.2
+    (void)a;
+}
 
 /* // */   // 3.1
 /* /* */   // 3.1