Commit Graph

8 Commits

Author SHA1 Message Date
Philip Reames f562fc8dbf [LICM] Hoist stores of invariant values to invariant addresses out of loops
Teach LICM to hoist stores out of loops when the store writes to a location otherwise unused in the loop, writes a value which is invariant, and is guaranteed to execute if the loop is entered.

Worth noting is that this transformation is partially overlapping with the existing promotion transformation. Reasons this is worthwhile anyway include:
 * For multi-exit loops, this doesn't require duplication of the store.
 * It kicks in for case where we can't prove we exit through a normal exit (i.e. we may throw), but can prove the store executes before that possible side exit.

Differential Revision: https://reviews.llvm.org/D50925

llvm-svn: 340974
2018-08-29 21:49:30 +00:00
Adam Nemet 358433ce1b [LICM] Report successful hoist/sink/promotion
Differential Revision: https://reviews.llvm.org/D27938

llvm-svn: 291646
2017-01-11 04:39:35 +00:00
Dehao Chen 9cba1f4e7e New pass manager for LICM.
Summary: Port LICM to the new pass manager.

Reviewers: davidxl, silvas

Subscribers: krasin, vitalybuka, silvas, davide, sanjoy, llvm-commits, mehdi_amini

Differential Revision: http://reviews.llvm.org/D21772

llvm-svn: 275222
2016-07-12 22:37:48 +00:00
Vitaly Buka 204dc533c5 Revert "New pass manager for LICM."
Summary: This reverts commit r275118.

Subscribers: sanjoy, mehdi_amini

Differential Revision: http://reviews.llvm.org/D22259

llvm-svn: 275156
2016-07-12 06:25:32 +00:00
Dehao Chen 7ef5820fa3 New pass manager for LICM.
Summary: Port LICM to the new pass manager.

Reviewers: davidxl, silvas

Subscribers: silvas, davide, sanjoy, llvm-commits, mehdi_amini

Differential Revision: http://reviews.llvm.org/D21772

llvm-svn: 275118
2016-07-11 22:45:24 +00:00
David Majnemer b33f3a239a [LICM] Fix a small oversight introduced in r256763
r256763 had promoteLoopAccessesToScalars check for the existence of a
catchswitch when the exit blocks were populated but
promoteLoopAccessesToScalars may be called with a prepopulated set of
exit blocks which would also need to be checked.

This fixes PR26019.

llvm-svn: 256788
2016-01-04 23:16:22 +00:00
David Majnemer 219055f9df [LICM] Don't insert instructions after a catchswitch when performing loop promotion
Inserting after a catchswitch results in verifier errors, bail out on
promotion if a catchswitch is a loop exit.

llvm-svn: 256763
2016-01-04 17:42:19 +00:00
David Majnemer 42a0730c42 [LICM] Make instruction sinking funclet-aware
We had two bugs here:
- We might try to sink into a catchswitch, causing verifier failures.
- We will succeed in sinking into a cleanuppad but we didn't update the
  funclet operand bundle.

This fixes PR26000.

llvm-svn: 256728
2016-01-04 03:37:39 +00:00