Commit Graph

14 Commits

Author SHA1 Message Date
Craig Topper e39c7ab2b9 [CostModel][X86][ARM] Teach default implementation of getCastInstrCost to not add a split/join cost if source type and the destination type both have a SplitVector action
If both the source and the destination need to be split then the two halves of the split operation are completely independent and don't need to be split or joined. So we don't need to assess a cost for the split or join.

Differential Revision: https://reviews.llvm.org/D79111
2020-05-01 18:55:23 -07:00
Craig Topper b938168aef [X86] Lower the cost of v4i64->v4i32 truncate with avx512.
We use the vpmovqd instruction which is a single uop. So
the cost should be 1.
2020-05-01 11:09:37 -07:00
Craig Topper cff6686532 [X86] Lower the cost of v4i64->v4i32 and v8i64->v8i32 truncate with AVX
We generate much better code these days than we used to. And we use the same sequence for AVX1 and AVX2 for these

For v4i64->v4i32 we generate:
vextractf128    xmm1, ymm0, 1
vshufps xmm0, xmm0, xmm1, 136   # xmm0 = xmm0[0,2],xmm1[0,2]

And for v8i64->v8i32 we generate:
vperm2f128      ymm2, ymm0, ymm1, 49 # ymm2 = ymm0[2,3],ymm1[2,3]
vinsertf128     ymm0, ymm0, xmm1, 1
vshufps ymm0, ymm0, ymm2, 136   # ymm0 = ymm0[0,2],ymm2[0,2],ymm0[4,6],ymm2[4,6]

Differential Revision: https://reviews.llvm.org/D79109
2020-04-29 13:21:44 -07:00
Craig Topper bdbbed115f [X86][CostModel] Update costs for vector truncate with avx512f/avx512bw.
All avx512 truncate instructions except vXi64->vXi32 are 2 uops
on port 5. So raise their costs to 2. Except when we have an
earlier faster sequence like pshufb for 128 bit input vectors.

Add a lower cost of 3 v16i16->v16i8 with avx512f where we can
extend to v16i32 then truncate. And a cost of 2 for avx512bw with
and without avx512vl. There we can use vpmovwb with either a ymm
or zmm input. Both of these beat masking, splitting, and using
packuswb which is our avx/avx2 codegen.
2020-04-27 12:00:24 -07:00
Craig Topper 8dfb9627b7 [X86] Make v32i16/v64i8 legal types without avx512bw. Use custom splitting instead.
This moves v32i16/v64i8 to a model consistent with how we
treat integer types with avx1.

This does change the ABI for types vXi16/vXi8 vectors larger than
512 bits to pass in multiple zmms instead of multiple ymms. We'd
already hacked some code to make v64i8/v32i16 pass in zmm.

Cost model is still a bit of a mess. In some place I tried to
match existing behavior. But really we need to account for
splitting and concating costs. Cost model for shuffles is
especially pessimistic.

Differential Revision: https://reviews.llvm.org/D76212
2020-04-15 12:17:18 -07:00
Craig Topper b2da1ddaef [X86] Add a non-zero cost for truncating v32i16->v32i8 on avx512bw. 2020-03-15 17:18:46 -07:00
Simon Pilgrim eaa41e103c [CostModel][X86] Try to check against common prefixes before using target-specific cpu checks
SLM/GLM is still a mess so not all of them have been updated yet.
2020-02-24 11:59:07 +00:00
Craig Topper 35625464c6 [X86] Fix the cost model for v16i16->v16i32 zero_extend/sign_extend with AVX2
We seem to be inheriting the cost from sse4.1. But if we have 256-bit registers we should be able to do this with just one extract to split the 16i16 and two v8i16->v8i32 operations so our cost should be 3 not 4.

Differential Revision: https://reviews.llvm.org/D73646
2020-01-29 15:52:10 -08:00
Simon Pilgrim d7f0207d73 [CostModel][X86] Fix SLM <2 x i64> icmp costs
SLM is 2 x slower for <2 x i64> comparison ops than other vector types, we should account for this like we do for SLM <2 x i64> add/sub/mul costs.

This should remove some of the SLM codegen diffs in D43582

llvm-svn: 372954
2019-09-26 10:14:38 +00:00
Simon Pilgrim 665ccbff60 [Cost][X86] Add v2i64 truncation costs
We are missing costs for a lot of truncation cases, I'm hoping to address all the 'zero cost' cases in trunc.ll

I thought this was a vector widening side effect, but even before this we had some interesting LV decisions (notably over indvars) being made due to these zero costs.

llvm-svn: 372498
2019-09-22 12:04:38 +00:00
Simon Pilgrim 42bf2dd629 [TTI] Add generic cost model for smul/umul overflow intrinsics
Based off smul/umul fixed costs and the implementation in TargetLowering::expandMULO.

llvm-svn: 354784
2019-02-25 13:30:23 +00:00
Simon Pilgrim 47ca8606ba [TTI] Add generic SADDO/SSUBO costs
Added x86 scalar sadd_with_overflow/ssub_with_overflow costs.

llvm-svn: 352045
2019-01-24 13:36:45 +00:00
Simon Pilgrim 2d1964b90f [TTI] Add generic UADDO/USUBO costs
Added x86 scalar uadd_with_overflow/usub_with_overflow costs.

Differential Revision: https://reviews.llvm.org/D56907

llvm-svn: 352043
2019-01-24 12:10:20 +00:00
Simon Pilgrim f87226eb70 [IR] Match intrinsic parameter by scalar/vectorwidth
This patch replaces the existing LLVMVectorSameWidth matcher with LLVMScalarOrSameVectorWidth.

The matching args must be either scalars or vectors with the same number of elements, but in either case the scalar/element type can differ, specified by LLVMScalarOrSameVectorWidth.

I've updated the _overflow intrinsics to demonstrate this - allowing it to return a i1 or <N x i1> overflow result, matching the scalar/vectorwidth of the other (add/sub/mul) result type.

The masked load/store/gather/scatter intrinsics have also been updated to use this, although as we specify the reference type to be llvm_anyvector_ty we guarantee the mask will be <N x i1> so no change in behaviour

Differential Revision: https://reviews.llvm.org/D57090

llvm-svn: 351957
2019-01-23 16:00:22 +00:00