Commit Graph

8 Commits

Author SHA1 Message Date
Simon Pilgrim 532a0f122e [SLPVectorizer] Add basic support for mul/and/or/xor horizontal reductions
Expand arithmetic reduction to include mul/and/or/xor instructions.

This patch just fixes the SLPVectorizer - the effective reduction costs for AVX1+ are still poor (see rL344846) and will need to be improved before SLP sees this as a valid transform - but we can already see the effect on SSE2 tests.

This partially helps PR37731, but doesn't fix it all as it still falls over on the extraction/reduction order for some reason.

Differential Revision: https://reviews.llvm.org/D53473

llvm-svn: 345037
2018-10-23 15:13:09 +00:00
Simon Pilgrim 0c35aa114d [SLPVectorizer][X86] Add mul/and/or/xor unrolled reduction tests
We miss arithmetic reduction for everything but Add/FAdd (I assume because that's the only cases which x86 has horizontal ops for.....)

llvm-svn: 344849
2018-10-20 15:17:27 +00:00
Alexey Bataev 1e593fe73e [SLP] Update test checks, NFC.
llvm-svn: 324387
2018-02-06 20:00:05 +00:00
Alexey Bataev 62af7252f1 [SLP] Fixed cost model for horizontal reduction.
Currently when cost of scalar operations is evaluated the vector type is
used for scalar operations. Patch fixes this issue and fixes evaluation
of the vector operations cost.
Several test showed that vector cost model is too optimistic. It
allowed vectorization of 8 or less add/fadd operations, though scalar
code is faster. Actually, only for 16 or more operations vector code
provides better performance.

Differential Revision: https://reviews.llvm.org/D26277

llvm-svn: 288398
2016-12-01 18:42:42 +00:00
Alexey Bataev fc617690ab [SLP] Additional tests with the cost of vector operations.
llvm-svn: 288377
2016-12-01 17:26:54 +00:00
Alexey Bataev e59a8351d0 Revert "[SLP] Additional tests with the cost of vector operations."
This reverts commit a61718435fc4118c82f8aa6133fd81f803789c1e.

llvm-svn: 288371
2016-12-01 16:45:04 +00:00
Alexey Bataev 2ff768475d [SLP] Additional tests with the cost of vector operations.
llvm-svn: 288369
2016-12-01 16:11:48 +00:00
Alexey Bataev 6ad5da7c81 [SLPVectorizer] Fix for PR25748: reduction vectorization after loop
unrolling.

The next code is not vectorized by the SLPVectorizer:
```
 int test(unsigned int *p) {
  int sum = 0;
  for (int i = 0; i < 8; i++)
    sum += p[i];
  return sum;
 }
```
During optimization this loop is fully unrolled and SLPVectorizer is
unable to vectorize it. Patch tries to fix this problem.

Differential Revision: https://reviews.llvm.org/D24796

llvm-svn: 283535
2016-10-07 09:39:22 +00:00