[AMDGPU] Add intrinsic for raw atomic buffer loads (#97707)

Upstream the intrinsics `llvm.amdgcn.raw.atomic.buffer.load`
and `llvm.amdgcn.raw.atomic.ptr.buffer.load`.

These additional intrinsics mark atomic buffer loads
as atomic to LLVM by removing the `IntrReadMem`
attribute. Otherwise, it could hoist these
intrinsics out of loops in cases where LLVM marks
them as invariant. That can cause issues such as
infinite loops.

Continuation of https://reviews.llvm.org/D138786
with the additional use in the fat buffer lowering,
more test cases and the additional ptr versions 
of these intrinsics.

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Co-authored-by: rtayl <>
Co-authored-by: Jay Foad <jay.foad@amd.com>
Co-authored-by: Mariusz Sikora <mariusz.sikora@amd.com>

0 files changed, 0 insertions, 0 deletions