Commit Graph

21 Commits

Author SHA1 Message Date
Matt Arsenault 3dbeefa978 AMDGPU: Mark all unspecified CC functions in tests as amdgpu_kernel
Currently the default C calling convention functions are treated
the same as compute kernels. Make this explicit so the default
calling convention can be changed to a non-kernel.

Converted with perl -pi -e 's/define void/define amdgpu_kernel void/'
on the relevant test directories (and undoing in one place that actually
wanted a non-kernel).

llvm-svn: 298444
2017-03-21 21:39:51 +00:00
Matt Arsenault f0a88dbaab LoadStoreVectorizer: Split even sized illegal chains properly
Implement isLegalToVectorizeLoadChain for AMDGPU to avoid
producing private address spaces accesses that will need to be
split up later. This was doing the wrong thing in the case
where the queried chain was an even number of elements.

A possible <4 x i32> store was being split into
store <2 x i32>
store i32
store i32

rather than
store <2 x i32>
store <2 x i32>

when legal.

llvm-svn: 295933
2017-02-23 03:58:53 +00:00
Alina Sbirlea a3d2f703a5 [LoadStoreVectorizer] Enable vectorization of stores in the presence of an aliasing load
Summary:
The "getVectorizablePrefix" method would give up if it found an aliasing load for a store chain.
In practice, the aliasing load can be treated as a memory barrier and all stores that precede it
are a valid vectorizable prefix.
Issue found by volkan in D26962. Testcase is a pruned version of the one in the original patch.

Reviewers: jlebar, arsenm, tstellarAMD

Subscribers: mzolotukhin, wdng, nhaehnle, anna, volkan, llvm-commits

Differential Revision: https://reviews.llvm.org/D27008

llvm-svn: 287781
2016-11-23 17:43:15 +00:00
Tom Stellard 64a9d0876c AMDGPU/SI: Don't allow unaligned scratch access
Summary: The hardware doesn't support this.

Reviewers: arsenm

Subscribers: kzhuravl, wdng, nhaehnle, yaxunl, llvm-commits, tony-tye

Differential Revision: https://reviews.llvm.org/D25523

llvm-svn: 284257
2016-10-14 18:10:39 +00:00
Matt Arsenault 950a82047b LSV: Fix incorrectly increasing alignment
If the unaligned access has a dynamic offset, it may be odd which
would make the adjusted alignment incorrect to use.

llvm-svn: 281110
2016-09-09 22:20:14 +00:00
Justin Lebar 3a5f40c191 [LSV] Use the original loads' names for the extractelement instructions.
Summary:
LSV replaces multiple adjacent loads with one vectorized load and a
bunch of extractelement instructions.  This patch makes the
extractelement instructions' names match those of the original loads,
for (hopefully) improved readability.

Reviewers: asbirlea, tstellarAMD

Subscribers: arsenm, mzolotukhin

Differential Revision: https://reviews.llvm.org/D23748

llvm-svn: 280818
2016-09-07 15:49:48 +00:00
Alina Sbirlea 3f8f7840bf [LoadStoreVectorizer] Change VectorSet to Vector to match head and tail positions. Resolves PR29148.
Summary:
LSV was using two vector sets (heads and tails) to track pairs of adjiacent position to vectorize.
A recent optimization is trying to obtain the longest chain to vectorize and assumes the positions
in heads(H) and tails(T) match, which is not the case is there are multiple tails for the same head.

e.g.:
i1: store a[0]
i2: store a[1]
i3: store a[1]
Leads to:
H: i1
T: i2 i3
Instead of:
H: i1 i1
T: i2 i3
So the positions for instructions that follow i3 will have different indexes in H/T.
This patch resolves PR29148.

This issue also surfaced the fact that if the chain is too long, and TLI
returns a "not-fast" answer, the whole chain will be abandoned for
vectorization, even though a smaller one would be beneficial.
Added a testcase and FIXME for this.

Reviewers: tstellarAMD, arsenm, jlebar

Subscribers: mzolotukhin, wdng, llvm-commits

Differential Revision: https://reviews.llvm.org/D24057

llvm-svn: 280179
2016-08-30 23:53:59 +00:00
Justin Lebar 6114b37838 [LSV] Don't assume that loads/stores appear in address order in the BB.
Summary:
getVectorizablePrefix previously didn't work properly in the face of
aliasing loads/stores.  It unwittingly assumed that the loads/stores
appeared in the BB in address order.  If they didn't, it would do the
wrong thing.

Reviewers: asbirlea, tstellarAMD

Subscribers: arsenm, llvm-commits, mzolotukhin

Differential Revision: https://reviews.llvm.org/D22535

llvm-svn: 276072
2016-07-20 00:55:12 +00:00
Justin Lebar 8778c62629 [LSV] Insert stores at the right point.
Summary:
Previously, the insertion point for stores was the last instruction in
Chain *before calling getVectorizablePrefixEndIdx*.  Thus if
getVectorizablePrefixEndIdx didn't return Chain.size(), we still would
insert at the last instruction in Chain.

This patch changes our internal API a bit in an attempt to make it less
prone to this sort of error.  As a result, we end up recalculating the
Chain's boundary instructions, but I think worrying about the speed hit
of this is a premature optimization right now.

Reviewers: asbirlea, tstellarAMD

Subscribers: mzolotukhin, arsenm, llvm-commits

Differential Revision: https://reviews.llvm.org/D22534

llvm-svn: 276056
2016-07-19 23:19:20 +00:00
Alina Sbirlea cbc6ac2afd Correct ordering of loads/stores.
Summary:
Aiming to correct the ordering of loads/stores. This patch changes the
insert point for loads to the position of the first load.
It updates the ordering method for loads to insert before, rather than after.

Before this patch the following sequence:
"load a[1], store a[1], store a[0], load a[2]"
Would incorrectly vectorize to "store a[0,1], load a[1,2]".
The correctness check was assuming the insertion point for loads is at
the position of the first load, when in practice it was at the last
load. An alternative fix would have been to invert the correctness check.
The current fix changes insert position but also requires reordering of
instructions before the vectorized load.

Updated testcases to reflect the changes.

Reviewers: tstellarAMD, llvm-commits, jlebar, arsenm

Subscribers: mzolotukhin

Differential Revision: http://reviews.llvm.org/D22071

llvm-svn: 275117
2016-07-11 22:34:29 +00:00
Alina Sbirlea 327955e057 Add TLI.allowsMisalignedMemoryAccesses to LoadStoreVectorizer
Summary: Extend TTI to access TLI.allowsMisalignedMemoryAccesses(). Check condition when vectorizing load and store chains.
Add additional parameters: AddressSpace, Alignment, Fast.

Reviewers: llvm-commits, jlebar

Subscribers: arsenm, mzolotukhin

Differential Revision: http://reviews.llvm.org/D21935

llvm-svn: 275100
2016-07-11 20:46:17 +00:00
Alina Sbirlea 8d8aa5dd6c Address two correctness issues in LoadStoreVectorizer
Summary:
GetBoundryInstruction returns the last instruction as the instruction which follows or end(). Otherwise the last instruction in the boundry set is not being tested by isVectorizable().
Partially solve reordering of instructions. More extensive solution to follow.

Reviewers: tstellarAMD, llvm-commits, jlebar

Subscribers: escha, arsenm, mzolotukhin

Differential Revision: http://reviews.llvm.org/D21934

llvm-svn: 274389
2016-07-01 21:44:12 +00:00
Matt Arsenault 0101ecade0 LoadStoreVectorizer: Don't increase alignment with no align set
If no alignment was set on the load/stores, it would vectorize
to the new type even though this increases the default alignment.

llvm-svn: 274323
2016-07-01 02:09:38 +00:00
Matt Arsenault 370e8226c7 LoadStoreVectorizer: Check TTI for vec reg bit width
llvm-svn: 274322
2016-07-01 02:07:22 +00:00
Matt Arsenault 42ad17059a LoadStoreVectorizer: Fix assert when merging pointer ops
This needs to use inttoptr/ptrtoint if combining an int and pointer
load. If a pointer is used always do an integer load.

llvm-svn: 274321
2016-07-01 01:55:52 +00:00
Matt Arsenault 241f34cde8 LoadStoreVectorizer: Use AA metadata
This was not passing the full instruction with metadata
to the alias query.

llvm-svn: 274318
2016-07-01 01:47:46 +00:00
Matt Arsenault d7e8898bdd LoadStoreVectorizer: if one element of a vector is integer, default to
integer.

Fixes issues on some architectures where we use arithmetic ops to build
vectors, which can cause bad things to happen for loads/stores of mixed
types.

Patch by Fiona Glaser

llvm-svn: 274307
2016-07-01 00:37:01 +00:00
Matt Arsenault 8a4ab5e19f LoadStoreVectorizer: Fix crashes on sub-byte types
llvm-svn: 274306
2016-07-01 00:36:54 +00:00
Matt Arsenault 079d0f19a2 LoadStoreVectorizer: Check skipFunction first.
Also add test I forgot to add to r274296.

llvm-svn: 274299
2016-06-30 23:50:18 +00:00
Matt Arsenault 2cbe52b990 LoadStoreVectorizer: Skip optnone functions
llvm-svn: 274296
2016-06-30 23:30:29 +00:00
Matt Arsenault 08debb0244 Add LoadStoreVectorizer pass
This was contributed by Apple, and I've been working on
minimal cleanups and generalizing it.

llvm-svn: 274293
2016-06-30 23:11:38 +00:00