calculate.h: cleaned up way too specific protections against potentia…

…l FPE
danmar · Jan 7, 2025 · f8fdc21 · f8fdc21
1 parent ef3337d
commit f8fdc21
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Showing 2 changed files with 24 additions and 4 deletions.
diff --git a/lib/calculate.h b/lib/calculate.h
@@ -63,14 +63,14 @@ R calculate(const std::string& s, const T& x, const T& y, bool* error = nullptr)
     case '*':
         return wrap(x * y);
     case '/':
-        if (isZero(y) || (std::is_integral<T>{} && std::is_signed<T>{} && isEqual(y, T(-1)) && isEqual(x, std::numeric_limits<T>::min()))) {
+        if (isZero(y) || (std::is_signed<T>{} && y < 0)) {
             if (error)
                 *error = true;
             return R{};
         }
         return wrap(x / y);
     case '%':
-        if (isZero(MathLib::bigint(y)) || (std::is_integral<T>{} && std::is_signed<T>{} && isEqual(y, T(-1)) && isEqual(x, std::numeric_limits<T>::min()))) {
+        if (isZero(MathLib::bigint(y)) || (std::is_signed<T>{} && MathLib::bigint(y) < 0)) {
             if (error)
                 *error = true;
             return R{};

diff --git a/test/testvalueflow.cpp b/test/testvalueflow.cpp
@@ -951,15 +951,35 @@ class TestValueFlow : public TestFixture {
         ASSERT_EQUALS(10, valueOfTok("x = static_cast<int>(10);", "( 10 )").intvalue);
         ASSERT_EQUALS(0, valueOfTok("x = sizeof (struct {int a;}) * 0;", "*").intvalue);
 
-        // Don't calculate if there is UB
+        // Don't calculate or crash if there is UB or invalid operations
         ASSERT(tokenValues(";-1<<10;","<<").empty());
         ASSERT(tokenValues(";10<<-1;","<<").empty());
         ASSERT(tokenValues(";10<<64;","<<").empty());
         ASSERT(tokenValues(";-1>>10;",">>").empty());
         ASSERT(tokenValues(";10>>-1;",">>").empty());
         ASSERT(tokenValues(";10>>64;",">>").empty());
+        ASSERT_EQUALS(tokenValues(";1%-1;","%").size(), 1);
+        ASSERT_EQUALS(tokenValues(";1%-10;","%").size(), 1);
+        ASSERT_EQUALS(tokenValues(";1.5%-1;","%").size(), 1);
+        ASSERT_EQUALS(tokenValues(";1.5%-10;","%").size(), 1);
+        ASSERT(tokenValues(";1%-1.5;","%").empty());
+        ASSERT(tokenValues(";1%-10.5;","%").empty());
+        ASSERT(tokenValues(";1.5%-1.5;","%").empty());
+        ASSERT(tokenValues(";1.5%-10.5;","%").empty());
+        ASSERT(tokenValues(";1/-1;","/").empty());
+        ASSERT(tokenValues(";1/-10;","/").empty());
+        ASSERT(tokenValues(";1.5/-1;","/").empty());
+        ASSERT(tokenValues(";1.5/-10;","/").empty());
+        ASSERT(tokenValues(";1/-1.5;","/").empty());
+        ASSERT(tokenValues(";1/-10.5;","/").empty());
+        ASSERT(tokenValues(";1.5/-1.5;","/").empty());
+        ASSERT(tokenValues(";1.5/-10.5;","/").empty());
+        ASSERT(tokenValues(";1/0;","/").empty());
+        ASSERT(tokenValues(";1/0;","/").empty());
+        ASSERT(tokenValues(";1.5/0;","/").empty());
+        ASSERT(tokenValues(";1.5/0;","/").empty());
         ASSERT(tokenValues(";((-1) * 9223372036854775807LL - 1) / (-1);", "/").empty()); // #12109
-        ASSERT_EQUALS(tokenValues(";((-1) * 9223372036854775807LL - 1) % (-1);", "%").size(), 1);
+        ASSERT_EQUALS(tokenValues(";((-1) * 9223372036854775807LL - 1) % (-1);", "%").size(), 1); // #12109
 
         code = "float f(const uint16_t& value) {\n"
                "    const uint16_t uVal = value; \n"