I have some random questions concerning types in the GIMPLE IR that I
would appreciate some clarification on.
Type safety
-----------
Some transformations treat 1-bit types as a synonym of _Bool and mix the
types in expressions, such as:
<unnamed-unsigned:1> _2;
_Bool _3;
_Bool _4;
...
_4 = _2 ^ _3;
and similarly mixing _Bool and enum
enum E:bool { E0, E1 };
in one operation.
I had expected this to be invalid... What are the type safety rules in the
GIMPLE IR?
Somewhat related, gcc.c-torture/compile/pr96796.c performs a
VIEW_CONVERT_EXPR from
struct S1 {
long f3;
char f4;
} g_3_4;
to an int
p_51_9 = VIEW_CONVERT_EXPR<int>(g_3_4);
That must be wrong?
Semantics of <signed-boolean:32>
--------------------------------
"Wide" Booleans, such as <signed-boolean:32>, seems to allow more values
than 0 and 1. For example, I've seen some IR operations like:
_66 = _16 ? _Literal (<signed-boolean:32>) -1 : 0;
But I guess there must be some semantic difference between
<signed-boolean:32> and a 32-bit int, otherwise the wide Boolean type
would not be needed... So what are the difference?
/Krister
