This PR adds a amdgns_load_to_lds intrinsic that abstracts over loads to
LDS from global (address space 1) pointers and buffer fat pointers
(address space 7), since they use the same API and "gather from a
pointer to LDS" is something of an abstract operation.
This commit adds the intrinsic and its lowerings for addrspaces 1 and 7,
and updates the MLIR wrappers to use it (loosening up the restrictions
on loads to LDS along the way to match the ground truth from target
features).
It also plumbs the intrinsic through to clang.
Since e39f6c1844fab59c638d8059a6cf139adb42279a opt will infer the
correct datalayout when given a triple. Avoid explicitly specifying it
in tests that depend on the AMDGPU target being present to avoid the
string becoming out of sync with the TargetInfo value.
Only tests with REQUIRES: amdgpu-registered-target or a local lit.cfg
were updated to ensure that tests for non-target-specific passes that
happen to use the AMDGPU layout still pass when building with a limited
set of targets.
Reviewed By: shiltian, arsenm
Pull Request: https://github.com/llvm/llvm-project/pull/137921
This reverts commit d1a05721172272f7aab685b56d99e86814a15bff.
There was further discussion on the PR about whether the intinsics
should exist in this form.
Add a buffer_fat_ptr_load_lds intrinsic, by analogy with
global_load_lds, which enables using `ptr addrspace(7)` to set the rsrc
and offset arguments to raw_ptr_buffer_load_lds.
This PR updates AMDGPULowerBufferFatPointers to use the
InstSimplifyFolder
when creating IR during buffer fat pointer lowering.
This shouldn't cause any large functional changes and might improve the
quality of the generated code.
Since LowerBufferFatPointers runs before PreISelIntrinsicLowering, which
normally handles unsupported memcpy()s,, and since you can't have a
`noalias {ptr addrspace(8), i32}` becasue it crashes later passes,
manually expand memcpy()s involving buffer fat pointers to loops.
Additionally, though they're unlikely to be used, this commit adds
support for memset().
This commit doesn't implement writing direct-to-LDS loads as the
intrinsics, but leaves the option in the future.
