Commit Graph

5 Commits

Author SHA1 Message Date
Eric Christopher cee313d288 Revert "Temporarily Revert "Add basic loop fusion pass.""
The reversion apparently deleted the test/Transforms directory.

Will be re-reverting again.

llvm-svn: 358552
2019-04-17 04:52:47 +00:00
Eric Christopher a863435128 Temporarily Revert "Add basic loop fusion pass."
As it's causing some bot failures (and per request from kbarton).

This reverts commit r358543/ab70da07286e618016e78247e4a24fcb84077fda.

llvm-svn: 358546
2019-04-17 02:12:23 +00:00
Jingyue Wu f1edf3e88f [SLSR] garbage-collect unused instructions
Summary:
After we rewrite a candidate, the instructions used by the old form may
become unused. This patch cleans up these unused instructions so that we
needn't run DCE after SLSR.

Test Plan: removed -dce in all the SLSR tests

Reviewers: broune, meheff

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D9101

llvm-svn: 235410
2015-04-21 19:56:18 +00:00
Jingyue Wu 43885ebb3a [SLSR] handle candidate form (B + i * S)
Summary:
With this patch, SLSR may rewrite

S1: X = B + i * S
S2: Y = B + i' * S

to

S2: Y = X + (i' - i) * S

A secondary improvement: if (i' - i) is a power of 2, emit Y as X + (S << log(i' - i)). (S << log(i' -i)) is in a canonical form and thus more likely GVN'ed than (i' - i) * S.

Test Plan: slsr-add.ll

Reviewers: hfinkel, sanjoy, meheff, broune, eliben

Reviewed By: eliben

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D8983

llvm-svn: 235019
2015-04-15 16:46:13 +00:00
Jingyue Wu 177a81578f [SLSR] handle candidate form &B[i * S]
Summary:
This patch enhances SLSR to handle another candidate form &B[i * S]. If
we found two candidates

S1: X = &B[i * S]
S2: Y = &B[i' * S]

and S1 dominates S2, we can replace S2 with

Y = &X[(i' - i) * S]

Test Plan:
slsr-gep.ll
X86/no-slsr.ll: verify that we do not run SLSR on GEPs that already fit into
an addressing mode

Reviewers: eliben, atrick, meheff, hfinkel

Reviewed By: hfinkel

Subscribers: sanjoy, llvm-commits

Differential Revision: http://reviews.llvm.org/D7459

llvm-svn: 233286
2015-03-26 16:49:24 +00:00