Use the elementtype attribute introduced in D105407 for the
llvm.preserve.array/struct.index intrinsics. It carries the
element type of the GEP these intrinsics effectively encode.
This patch:
* Adds a verifier check that the attribute is required.
* Adds it in the IRBuilder methods for these intrinsics.
* Autoupgrades old bitcode without the attribute.
* Updates the lowering code to use the attribute rather than
the pointer element type.
* Updates lots of tests to specify the attribute.
* Adds -force-opaque-pointers to the intrinsic-array.ll test
to demonstrate they work now.
https://reviews.llvm.org/D106184
Commit c15aa241f8 ("[CLANG][BPF] change __builtin_preserve_access_index()
signature") changed the builtin function signature to
PointerT __builtin_preserve_access_index(PointerT ptr)
with a pointer type as the argument/return type, where argument and
return types must be the same.
There is really no reason for this constraint. The builtin just
presented a code region so that IR builtins
__builtin_{array, struct, union}_preserve_access_index
can be applied.
This patch removed the pointer type restriction to permit any
argument type as long as it is permitted by the compiler.
Differential Revision: https://reviews.llvm.org/D67883
llvm-svn: 372516
Nikita Popov