Sorry for not reacting to this earlier..
On Sat, Mar 11, 2017 at 7:47 AM, Luc Van Oostenryck
<luc.vanoostenryck@xxxxxxxxx> wrote:
> This is a RFC for giving a type to constants/PSEUDO_VALs.
This seems completely broken. Not from an implementation standpoint,
but from a conceptual one.
To explain, let me give a completely idiotic example:
unsigned int test(int arg)
{
return arg + (unsigned int)arg;
}
note how we're adding a "int" and an "unsigned int" together. But the
CSE etc doesn't actually care at all, and we will linearize this to
just
test:
add.32 %r5 <- %arg1, %arg1
ret.32 %r5
because the type just isn't relevant at the linearization phase.
You can tell that there *used* to be multiple pseudos from the
numbering ("%r5"? What happened to "%r1..4"?), but they have all been
smushed together.
Linearization has fundamentally gotten rid of all the C types, and all
you can find are some rough remnants of them (you can find the *size*
of the type, and you can find the rough "type" of type - is it a
pointer, FP value or integer. There aren't even any signs, although
some _operations_ are signed (but not the pseudos).
The same pseudo can have many different types.
Linus
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