10 Commits

Author SHA1 Message Date
Krzysztof Drewniak
f0415f2a45 Re-land "[AMDGPU] Define data layout entries for buffers""
Re-land D145441 with data layout upgrade code fixed to not break OpenMP.

This reverts commit 3f2fbe92d0f40bcb46db7636db9ec3f7e7899b27.

Differential Revision: https://reviews.llvm.org/D149776
2023-05-03 19:43:56 +00:00
Krzysztof Drewniak
3f2fbe92d0 Revert "[AMDGPU] Define data layout entries for buffers"
This reverts commit f9c1ede2543b37fabe9f2d8f8fed5073c475d850.

Differential Revision: https://reviews.llvm.org/D149758
2023-05-03 16:11:00 +00:00
Krzysztof Drewniak
f9c1ede254 [AMDGPU] Define data layout entries for buffers
Per discussion at
https://discourse.llvm.org/t/representing-buffer-descriptors-in-the-amdgpu-target-call-for-suggestions/68798,
we define two new address spaces for AMDGCN targets.

The first is address space 7, a non-integral address space (which was
already in the data layout) that has 160-bit pointers (which are
256-bit aligned) and uses a 32-bit offset. These pointers combine a
128-bit buffer descriptor and a 32-bit offset, and will be usable with
normal LLVM operations (load, store, GEP). However, they will be
rewritten out of existence before code generation.

The second of these is address space 8, the address space for "buffer
resources". These will be used to represent the resource arguments to
buffer instructions, and new buffer intrinsics will be defined that
take them instead of <4 x i32> as resource arguments. ptr
addrspace(8). These pointers are 128-bits long (with the same
alignment). They must not be used as the arguments to getelementptr or
otherwise used in address computations, since they can have
arbitrarily complex inherent addressing semantics that can't be
represented in LLVM. Even though, like their address space 7 cousins,
these pointers have deterministic ptrtoint/inttoptr semantics, they
are defined to be non-integral in order to prevent optimizations that
rely on pointers being a [0, [addr_max]] value from applying to them.

Future work includes:
- Defining new buffer intrinsics that take ptr addrspace(8) resources.
- A late rewrite to turn address space 7 operations into buffer
intrinsics and offset computations.

This commit also updates the "fallback address space" for buffer
intrinsics to the buffer resource, and updates the alias analysis
table.

Depends on D143437

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D145441
2023-05-03 15:25:58 +00:00
Dmitry Makogon
3d7242f05e Reapply "[LSR] Preserve LCSSA when rewriting instruction with PHI user"
This reverts commit efd34ba60f3839b0a68b2e32ff9011b6823bc16f.

Reapplies 8ff4832679e1. Missed a failing test. Needed to just
update test checks.
2023-04-06 17:31:27 +07:00
Nico Weber
efd34ba60f Revert "[LSR] Preserve LCSSA when rewriting instruction with PHI user"
This reverts commit 8ff4832679e1ff2d2a1cfaa45bb5cb995b0685a1.
Breaks tests, see https://reviews.llvm.org/D146811#4232839
2023-03-30 06:40:16 -04:00
Dmitry Makogon
8ff4832679 [LSR] Preserve LCSSA when rewriting instruction with PHI user
Fixes https://github.com/llvm/llvm-project/issues/61182.

LoopStrengthReduce may sometimes break LCSSA form when applying a rewrite
for an instruction used in a PHI.
It happens if:
 - The PHI is in a loop exit block,
 - The edge from the corresponding exiting block to that exit is critical,
 - The PHI has at least two inputs coming from loop blocks,
 - and the rewritten instruction is inserted in the loop.

In such case we split the critical edge and then replace PHI inputs
with the rewritten instruction. However ExitBlock is no longer
a loop exit, so LCSSA form is broken.

This patch fixes it by collecting all inserted instructions for PHIs
whose parent block is not a loop exit and then forming LCSSA for them.

Differential Revision: https://reviews.llvm.org/D146811
2023-03-30 14:46:28 +07:00
Dmitry Makogon
8e85bede79 [Test] Regenerate test checks for some LSR tests (NFC) 2023-03-24 21:24:22 +07:00
Matt Arsenault
aa65dba05c LoopStrengthReduce: Convert AMDGPU tests to opaque pointers 2023-01-27 22:17:20 -04:00
Nikita Popov
9ed2f14c87 [AsmParser] Remove typed pointer auto-detection
IR is now always parsed in opaque pointer mode, unless
-opaque-pointers=0 is explicitly given. There is no automatic
detection of typed pointers anymore.

The -opaque-pointers=0 option is added to any remaining IR tests
that haven't been migrated yet.

Differential Revision: https://reviews.llvm.org/D141912
2023-01-18 09:58:32 +01:00
Brendon Cahoon
c4c379d633 [LoopStrengthReduction] Fix pointer extend asserts
Additional asserts were added to ScalarEvolution to enforce
pointer/int type rules. An assert is triggered when the LSR pass
attempts to extend a pointer SCEV in GenerateTruncates.

This patch changes GenerateTruncates to exit early if the Formaula
contains a ScaledReg or BaseReg with a pointer type.

Differential Revision: https://reviews.llvm.org/D107185
2021-07-30 17:24:08 -04:00