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checkTypes: Take into account type promotion to integer.

This commit is contained in:
orbitcowboy 2018-02-19 23:55:38 +01:00
parent b1b3164259
commit b7b376d901
2 changed files with 32 additions and 110 deletions
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14
lib/checktype.cpp
View File

@ -72,12 +72,14 @@ void CheckType::checkTooBigBitwiseShift()
const ValueType * const lhstype = tok->astOperand1()->valueType();
if (!lhstype || !lhstype->isIntegral() || lhstype->pointer >= 1U)
continue;
int lhsbits = 0;
if (lhstype->type == ValueType::Type::CHAR)
lhsbits = _settings->char_bit;
else if (lhstype->type == ValueType::Type::SHORT)
lhsbits = _settings->short_bit;
else if (lhstype->type == ValueType::Type::INT)
// C11 Standard, section 6.5.7 Bitwise shift operators, states:
// The integer promotions are performed on each of the operands.
// The type of the result is that of the promoted left operand.
int lhsbits;
if ((lhstype->type == ValueType::Type::CHAR) ||
(lhstype->type == ValueType::Type::SHORT) ||
(lhstype->type == ValueType::Type::BOOL) ||
(lhstype->type == ValueType::Type::INT))
lhsbits = _settings->int_bit;
else if (lhstype->type == ValueType::Type::LONG)
lhsbits = _settings->long_bit;

128
test/testtype.cpp
View File

@ -65,113 +65,33 @@ private:
Settings settings;
settings.platform(Settings::Unix32);
// 8 bit width types
// unsigned types getting promoted to int sizeof(int) = 4 bytes
// and unsigned types having already a size of 4 bytes
{
// unsigned char
check("unsigned char foo(unsigned char x) { return x << 8; }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 8-bit value by 8 bits is undefined behaviour\n", errout.str());
check("unsigned char f(int x) { return (x = (unsigned char)x << 8); }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 8-bit value by 8 bits is undefined behaviour\n", errout.str());
check("unsigned char foo(unsigned char x) { return x << 7; }",&settings);
ASSERT_EQUALS("", errout.str());
// [unsigned] char
check("char foo(char x) { return x << 8; }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 8-bit value by 8 bits is undefined behaviour\n", errout.str());
check("char f(int x) { return (x = (char)x << 8); }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 8-bit value by 8 bits is undefined behaviour\n", errout.str());
check("char foo(char x) { return x << 7; }",&settings);
ASSERT_EQUALS("", errout.str());
// signed char
check("signed char foo(signed char x) { return x << 8; }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 8-bit value by 8 bits is undefined behaviour\n", errout.str());
check("signed char f(int x) { return (x = (signed char)x << 8); }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 8-bit value by 8 bits is undefined behaviour\n", errout.str());
check("signed char foo(signed char x) { return x << 7; }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting signed 8-bit value by 7 bits is undefined behaviour\n", errout.str());
check("signed char foo(signed char x) { return x << 6; }",&settings);
ASSERT_EQUALS("", errout.str());
const std::string type[6] = {"unsigned char", /*[unsigned]*/"char", "bool", "unsigned short", "unsigned int", "unsigned long"};
for (uint8_t i = 0; i < 6U; ++i) {
check((type[i] + " f(" + type[i] +" x) { return x << 33; }").c_str(),&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 32-bit value by 33 bits is undefined behaviour\n", errout.str());
check((type[i] + " f(int x) { return (x = (" + type[i] + ")x << 32); }").c_str(),&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 32-bit value by 32 bits is undefined behaviour\n", errout.str());
check((type[i] + " foo(" + type[i] + " x) { return x << 31; }").c_str(),&settings);
ASSERT_EQUALS("", errout.str());
}
}
// 16 bit width types
// signed types getting promoted to int sizeof(int) = 4 bytes
// and signed types having already a size of 4 bytes
{
// unsigned short
check("unsigned short foo(unsigned short x) { return x << 16; }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 16-bit value by 16 bits is undefined behaviour\n", errout.str());
check("unsigned short f(int x) { return (x = (unsigned short)x << 31); }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 16-bit value by 31 bits is undefined behaviour\n", errout.str());
check("unsigned short foo(unsigned short x) { return x << 15; }",&settings);
ASSERT_EQUALS("", errout.str());
// [signed] short
check("short foo(short x) { return x << 16; }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 16-bit value by 16 bits is undefined behaviour\n", errout.str());
check("short f(int x) { return (x = (short)x << 31); }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 16-bit value by 31 bits is undefined behaviour\n", errout.str());
check("short foo(short x) { return x << 15; }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting signed 16-bit value by 15 bits is undefined behaviour\n", errout.str());
check("short foo(short x) { return x << 14; }",&settings);
ASSERT_EQUALS("", errout.str());
// signed short
check("signed short foo(signed short x) { return x << 16; }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 16-bit value by 16 bits is undefined behaviour\n", errout.str());
check("signed short f(int x) { return (x = (signed short)x << 31); }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 16-bit value by 31 bits is undefined behaviour\n", errout.str());
check("signed short foo(signed short x) { return x << 15; }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting signed 16-bit value by 15 bits is undefined behaviour\n", errout.str());
check("signed short foo(signed short x) { return x << 14; }",&settings);
ASSERT_EQUALS("", errout.str());
}
// 32 bit width types
{
// unsigned int
check("unsigned int foo(unsigned int x) { return x << 32; }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 32-bit value by 32 bits is undefined behaviour\n", errout.str());
check("unsigned int f(int x) { return (x = (unsigned int)x << 32); }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 32-bit value by 32 bits is undefined behaviour\n", errout.str());
check("unsigned int f(unsigned int x) { return x << 31; }",&settings);
ASSERT_EQUALS("", errout.str());
// [signed] int
check("int foo(int x) { return x << 32; }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 32-bit value by 32 bits is undefined behaviour\n", errout.str());
check("int f(int x) { return (x = (int)x << 32); }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 32-bit value by 32 bits is undefined behaviour\n", errout.str());
check("int f(int x) { return x << 31; }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting signed 32-bit value by 31 bits is undefined behaviour\n", errout.str());
check("int f(int x) { return x << 30; }",&settings);
ASSERT_EQUALS("", errout.str());
// signed int
check("signed int foo(signed int x) { return x << 32; }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 32-bit value by 32 bits is undefined behaviour\n", errout.str());
check("signed int f(int x) { return (x = (signed int)x << 32); }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 32-bit value by 32 bits is undefined behaviour\n", errout.str());
check("signed int f(signed int x) { return x << 31; }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting signed 32-bit value by 31 bits is undefined behaviour\n", errout.str());
check("signed int f(signed int x) { return x << 30; }",&settings);
ASSERT_EQUALS("", errout.str());
// unsigned long
check("unsigned long foo(unsigned long x) { return x << 32; }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 32-bit value by 32 bits is undefined behaviour\n", errout.str());
check("unsigned long f(long x) { return (x = (unsigned long)x << 32); }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 32-bit value by 32 bits is undefined behaviour\n", errout.str());
check("unsigned long f(unsigned long x) { return x << 31; }",&settings);
ASSERT_EQUALS("", errout.str());
// [signed] long
check("long foo(long x) { return x << 32; }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 32-bit value by 32 bits is undefined behaviour\n", errout.str());
check("long f(long x) { return (x = (long)x << 32); }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 32-bit value by 32 bits is undefined behaviour\n", errout.str());
check("long f(long x) { return x << 31; }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting signed 32-bit value by 31 bits is undefined behaviour\n", errout.str());
check("long f(long x) { return x << 30; }",&settings);
ASSERT_EQUALS("", errout.str());
// signed long
check("signed long foo(signed long x) { return x << 32; }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 32-bit value by 32 bits is undefined behaviour\n", errout.str());
check("signed long f(long x) { return (x = (signed long)x << 32); }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 32-bit value by 32 bits is undefined behaviour\n", errout.str());
check("signed long f(signed long x) { return x << 31; }",&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting signed 32-bit value by 31 bits is undefined behaviour\n", errout.str());
check("signed long f(signed long x) { return x << 30; }",&settings);
ASSERT_EQUALS("", errout.str());
const std::string type[7] = {"signed char", "signed short", /*[signed]*/"short", /*[signed]*/"int", "signed int", /*[signed]*/"long", "signed long"};
for (uint8_t i = 0; i < 7U; ++i) {
check((type[i] + " f(" + type[i] +" x) { return x << 33; }").c_str(),&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 32-bit value by 33 bits is undefined behaviour\n", errout.str());
check((type[i] + " f(int x) { return (x = (" + type[i] + ")x << 32); }").c_str(),&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting 32-bit value by 32 bits is undefined behaviour\n", errout.str());
check((type[i] + " foo(" + type[i] + " x) { return x << 31; }").c_str(),&settings);
ASSERT_EQUALS("[test.cpp:1]: (error) Shifting signed 32-bit value by 31 bits is undefined behaviour\n", errout.str());
check((type[i] + " foo(" + type[i] + " x) { return x << 30; }").c_str(),&settings);
ASSERT_EQUALS("", errout.str());
}
}
// 64 bit width types
{