[clang][aarch64] Drop experimental from __ARM_FEATURE_SVE_BITS macro

Authored by c-rhodes on Sep 3 2020, 2:19 AM.


[clang][aarch64] Drop experimental from __ARM_FEATURE_SVE_BITS macro

The ARM_FEATURE_SVE_BITS feature macro is specified in the Arm C
Language Extensions (ACLE) for SVE [1] (version 00bet5). From the spec,

When N is nonzero, indicates that the implementation is generating
code for an N-bit SVE target and that the arm_sve_vector_bits(N)
attribute is available.

This was defined in D83550 as __ARM_FEATURE_SVE_BITS_EXPERIMENTAL and
enabled under the -msve-vector-bits flag to simplify initial tests.
This patch drops _EXPERIMENTAL now there is support for the feature.

[1] https://developer.arm.com/documentation/100987/latest

Reviewed By: david-arm

Differential Revision: https://reviews.llvm.org/D86720