(#131759)

This isn't really the right check, we want to know that the intrinsic
does not perform a true function call to any code (in the module or
not). nocallback
appears to be the closest thing to this property we have now though.
Fixes theoretically
miscompiles with intrinsics like statepoint, which hide a call to a real
function.

Also do the same for inferring no-agpr usage.

"const" is extraneous in the presence of "constexpr" for simple
variables and arrays.

 (#162300)

This now tries to compute a lower bound on the number of registers
for individual inline asm uses. Also starts using AACallEdges
to handling indirect calls.

Apparently the IR verifier doesn't enforce the correct structure.
Also I do not know why we have this extra level of wrapper in the
intrinsic,
it just makes it harder to get at the string. I also do not know why
kokkos is using these intrinsics, but it shouldn't.

Fix the special case intrinsics that can directly reference a physical
register. There's no reason to use this.

For now just try to compute the minimum number of AGPRs required
to allocate the asm. Leave the attributor changes to turn this
into an integer value for later.

This only matters for subtargets with configurable AGPR allocation.

Don't think this did anything harmful, but it doesn't make sense
to report this as implementing nounwind handling.

This PR stops the attributor pass to infer `amdgpu-no-flat-scratch-init`
for functions marked with `sanitize_*` attribute.