tree 91467721a03851ecc3bfb87f5715acd6932cb0e4
parent ec10cb25d93412b1ca0da354f9b52fe4fdfccc87
author Roman Lebedev <lebedev.ri@gmail.com> 1571646104 +0000
committer Roman Lebedev <lebedev.ri@gmail.com> 1571646104 +0000

[CVP] Deduce no-wrap on `mul`

Summary:
`ConstantRange::makeGuaranteedNoWrapRegion()` knows how to deal with `mul`
since rL335646, there is exhaustive test coverage.
This is already used by CVP's `processOverflowIntrinsic()`,
and by SCEV's `StrengthenNoWrapFlags()`

That being said, currently, this doesn't help much in the end:
| statistic                              |     old |     new | delta | percentage |
| correlated-value-propagation.NumMulNSW |       4 |     275 |   271 |   6775.00% |
| correlated-value-propagation.NumMulNUW |       4 |    1323 |  1319 |  32975.00% |
| correlated-value-propagation.NumMulNW  |       8 |    1598 |  1590 |  19875.00% |
| correlated-value-propagation.NumNSW    |    5715 |    5986 |   271 |      4.74% |
| correlated-value-propagation.NumNUW    |    9193 |   10512 |  1319 |     14.35% |
| correlated-value-propagation.NumNW     |   14908 |   16498 |  1590 |     10.67% |
| instcount.NumAddInst                   |  275871 |  275869 |    -2 |      0.00% |
| instcount.NumBrInst                    |  708234 |  708232 |    -2 |      0.00% |
| instcount.NumMulInst                   |   43812 |   43810 |    -2 |      0.00% |
| instcount.NumPHIInst                   |  316786 |  316784 |    -2 |      0.00% |
| instcount.NumTruncInst                 |   62165 |   62167 |     2 |      0.00% |
| instcount.NumUDivInst                  |    2528 |    2526 |    -2 |     -0.08% |
| instcount.TotalBlocks                  |  842995 |  842993 |    -2 |      0.00% |
| instcount.TotalInsts                   | 7376486 | 7376478 |    -8 |      0.00% |
(^ test-suite plain, tests still pass)

Reviewers: nikic, reames, luqmana, sanjoy, timshen

Reviewed By: reames

Subscribers: hiraditya, javed.absar, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69203

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@375396 91177308-0d34-0410-b5e6-96231b3b80d8