Commit Graph

11 Commits

Author SHA1 Message Date
Juneyoung Lee 9b29610228 Use unary CreateShuffleVector if possible
As mentioned in D93793, there are quite a few places where unary `IRBuilder::CreateShuffleVector(X, Mask)` can be used
instead of `IRBuilder::CreateShuffleVector(X, Undef, Mask)`.
Let's update them.

Actually, it would have been more natural if the patches were made in this order:
(1) let them use unary CreateShuffleVector first
(2) update IRBuilder::CreateShuffleVector to use poison as a placeholder value (D93793)

The order is swapped, but in terms of correctness it is still fine.

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D93923
2020-12-30 22:36:08 +09:00
Praveen Velliengiri 61177943c9 [AMDGPU] Use MUBUF instructions for global address space access
Currently, the compiler crashes in instruction selection of global
load/stores in gfx600 due to the lack of FLAT instructions. This patch
fix the crash by selecting MUBUF instructions for global load/stores
in gfx600.

Authored-by: Praveen Velliengiri <Praveen.Velliengiri@amd.com>

Reviewed by: t-tye

Differential revision: https://reviews.llvm.org/D92483
2020-12-24 10:13:04 +00:00
Matt Arsenault 1168119c2f AMDGPU: Start interpreting byref on kernel arguments
These are treated identically to value aggregates placed in the kernel
argument list. A %struct.foo or %struct.foo addrspace(4)*
byref(sizeof(%struct.foo)) align(alignof(%struct.foo)) argument should
produce the same offsets and argument metadata.

This handles all 3 kernel ABI implementations, and the two HSA
metadata emission paths.
2020-07-21 18:11:22 -04:00
Eli Friedman 4f04db4b54 AllocaInst should store Align instead of MaybeAlign.
Along the lines of D77454 and D79968.  Unlike loads and stores, the
default alignment is getPrefTypeAlign, to match the existing handling in
various places, including SelectionDAG and InstCombine.

Differential Revision: https://reviews.llvm.org/D80044
2020-05-16 14:53:16 -07:00
Matt Arsenault 074c371a48 AMDGPU: Insert kernarg code after allocas
This produces more normal looking IR by keeping all the allocas
clustered at the start of the block.
2020-05-06 10:19:56 -04:00
Matt Arsenault e0c1f9e76d AMDGPU: Partially fix default device for HSA
There are a few different issues, mostly stemming from using
generation based checks for anything instead of subtarget
features. Stop adding flat-address-space as a feature for HSA, as it
should only be a device property. This was incorrectly allowing flat
instructions to select for SI.

Increase the default generation for HSA to avoid the encoding error
when emitting objects. This has some other side effects from various
checks which probably should be separate subtarget features (in the
cost model and for dealing with the DS offset folding issue).

Partial fix for bug 41070. It should probably be an error to try using
amdhsa without flat support.

llvm-svn: 356347
2019-03-17 21:31:35 +00:00
James Y Knight 14359ef1b6 [opaque pointer types] Pass value type to LoadInst creation.
This cleans up all LoadInst creation in LLVM to explicitly pass the
value type rather than deriving it from the pointer's element-type.

Differential Revision: https://reviews.llvm.org/D57172

llvm-svn: 352911
2019-02-01 20:44:24 +00:00
Matt Arsenault 72b0e38b26 AMDGPU: Stop trying to extend arguments for clover
This was trying to replace i8/i16 arguments with i32, which
was broken and no longer necessary.

llvm-svn: 338193
2018-07-28 12:34:25 +00:00
Matt Arsenault f5be3ad7f8 AMDGPU: Don't use struct type for argument layout
This was introducing unnecessary padding after the explicit
arguments, depending on the alignment of the total struct type.
Also has the side effect of avoiding creating an extra GEP for
the offset from the base kernel argument to the explicit kernel
argument offset.

llvm-svn: 335999
2018-06-29 17:31:42 +00:00
Matt Arsenault 513e0c0ea4 AMDGPU: Fix assert on aggregate type kernel arguments
Just fix the crash for now by not doing the optimization since
figuring out how to properly convert the bits for an arbitrary
struct is a pain.

Also fix a crash when there is only an empty struct argument.

llvm-svn: 335827
2018-06-28 10:18:11 +00:00
Matt Arsenault 8c4a35237a AMDGPU: Add pass to lower kernel arguments to loads
This replaces most argument uses with loads, but for
now not all.

The code in SelectionDAG for calling convention lowering
is actively harmful for amdgpu_kernel. It attempts to
split the argument types into register legal types, which
results in low quality code for arbitary types. Since
all kernel arguments are passed in memory, we just want the
raw types.

I've tried a couple of methods of mitigating this in SelectionDAG,
but it's easier to just bypass this problem alltogether. It's
possible to hack around the problem in the initial lowering,
but the real problem is the DAG then expects to be able to use
CopyToReg/CopyFromReg for uses of the arguments outside the block.

Exposing the argument loads in the IR also has the advantage
that the LoadStoreVectorizer can merge them.

I'm not sure the best approach to dealing with the IR
argument list is. The patch as-is just leaves the IR arguments
in place, so all the existing code will still compute the same
kernarg size and pointlessly lowers the arguments.

Arguably the frontend should emit kernels with an empty argument
list in the first place. Alternatively a dummy array could be
inserted as a single argument just to reserve space.

This does have some disadvantages. Local pointer kernel arguments can
no longer have AssertZext placed  on them as the equivalent !range
metadata is not valid on pointer  typed loads. This is mostly bad
for SI which needs to know about the known bits in order to use the
DS instruction offset, so in this case this is not done.

More importantly, this skips noalias arguments since this pass
does not yet convert this to the equivalent !alias.scope and !noalias
metadata. Producing this metadata correctly seems to be tricky,
although this logically is the same as inlining into a function which
doesn't exist. Additionally, exposing these loads to the vectorizer
may result in degraded aliasing information if a pointer load is
merged with another argument load.

I'm also not entirely sure this is preserving the current clover
ABI, although I would greatly prefer if it would stop widening
arguments and match the HSA ABI. As-is I think it is extending
< 4-byte arguments to 4-bytes but doesn't align them to 4-bytes.

llvm-svn: 335650
2018-06-26 19:10:00 +00:00