Commit Graph

10 Commits

Author SHA1 Message Date
Teresa Johnson
99dd11f7e8 [PM] Split LoopUnrollPass and make partial unroller a function pass
Summary:
This is largely NFC*, in preparation for utilizing ProfileSummaryInfo
and BranchFrequencyInfo analyses. In this patch I am only doing the
splitting for the New PM, but I can do the same for the legacy PM as
a follow-on if this looks good.

*Not NFC since for partial unrolling we lose the updates done to the
loop traversal (adding new sibling and child loops) - according to
Chandler this is not very useful for partial unrolling, but it also
means that the debugging flag -unroll-revisit-child-loops no longer
works for partial unrolling.

Reviewers: chandlerc

Subscribers: mehdi_amini, mzolotukhin, eraman, llvm-commits

Differential Revision: https://reviews.llvm.org/D36157

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@309886 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-02 20:35:29 +00:00
Chandler Carruth
f541c74552 [PM] Teach LoopUnroll to update the LPM infrastructure as it unrolls
loops.

We do this by reconstructing the newly added loops after the unroll
completes to avoid threading pass manager details through all the mess
of the unrolling infrastructure.

I've enabled some extra assertions in the LPM to try and catch issues
here and enabled a bunch of unroller tests to try and make sure this is
sane.

Currently, I'm manually running loop-simplify when needed. That should
go away once it is folded into the LPM infrastructure.

Differential Revision: https://reviews.llvm.org/D28848

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293011 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-25 02:49:01 +00:00
Adam Nemet
c4f6d8cd25 [LoopUnroll] Include hotness of region in opt remark
LoopUnroll is a loop pass, so the analysis of OptimizationRemarkEmitter
is added to the common function analysis passes that loop passes
depend on.

The BFI and indirectly BPI used in this pass is computed lazily so no
overhead should be observed unless -pass-remarks-with-hotness is used.

This is how the patch affects the O3 pipeline:

         Dominator Tree Construction
         Natural Loop Information
         Canonicalize natural loops
         Loop-Closed SSA Form Pass
         Basic Alias Analysis (stateless AA impl)
         Function Alias Analysis Results
         Scalar Evolution Analysis
+        Lazy Branch Probability Analysis
+        Lazy Block Frequency Analysis
+        Optimization Remark Emitter
         Loop Pass Manager
           Rotate Loops
           Loop Invariant Code Motion
           Unswitch loops
         Simplify the CFG
         Dominator Tree Construction
         Basic Alias Analysis (stateless AA impl)
         Function Alias Analysis Results
         Combine redundant instructions
         Natural Loop Information
         Canonicalize natural loops
         Loop-Closed SSA Form Pass
         Scalar Evolution Analysis
+        Lazy Branch Probability Analysis
+        Lazy Block Frequency Analysis
+        Optimization Remark Emitter
         Loop Pass Manager
           Induction Variable Simplification
           Recognize loop idioms
           Delete dead loops
           Unroll loops
...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277203 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-29 19:29:47 +00:00
Sean Silva
d8c90ea6b8 [PM] Port LoopUnroll.
We just set PreserveLCSSA to always true since we don't have an
analogous method `mustPreserveAnalysisID(LCSSA)`.

Also port LoopInfo verifier pass to test LoopUnrollPass.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@276063 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-19 23:54:23 +00:00
Justin Bogner
fbbc16fa87 LoopInfo: Simplify ownership of Loop objects
It's strange that LoopInfo mostly owns the Loop objects, but that it
defers deleting them to the loop pass manager. Instead, change the
oddly named "updateUnloop" to "markAsRemoved" and have it queue the
Loop object for deletion. We can't delete the Loop immediately when we
remove it, since we need its pointer identity still, so we'll mark the
object as "invalid" so that clients can see what's going on.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@257191 91177308-0d34-0410-b5e6-96231b3b80d8
2016-01-08 19:08:53 +00:00
Stephen Lin
39f4e8d9cc Update Transforms tests to use CHECK-LABEL for easier debugging. No functionality change.
This update was done with the following bash script:

  find test/Transforms -name "*.ll" | \
  while read NAME; do
    echo "$NAME"
    if ! grep -q "^; *RUN: *llc" $NAME; then
      TEMP=`mktemp -t temp`
      cp $NAME $TEMP
      sed -n "s/^define [^@]*@\([A-Za-z0-9_]*\)(.*$/\1/p" < $NAME | \
      while read FUNC; do
        sed -i '' "s/;\(.*\)\([A-Za-z0-9_]*\):\( *\)@$FUNC\([( ]*\)\$/;\1\2-LABEL:\3@$FUNC(/g" $TEMP
      done
      mv $TEMP $NAME
    fi
  done


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186268 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-14 01:42:54 +00:00
Andrew Trick
cd8e3c4dcf Prevent loop-unroll from making assumptions about undefined behavior.
Fixes rdar:14036816, PR16130.

There is an opportunity to compute precise trip counts for 'or'
expressions and multi-exit loops.
rdar:14038809: Optimize trip count computation for multi-exit loops.

To do this we need to record the fact that ExitLimit assumes NSW. When
it does not we can safely assume that the loop trip count is the
minimum ExitLimt across all subexpressions and loop exits.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183060 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-31 23:34:46 +00:00
Andrew Trick
5865a8dfde Fix a corner case in updating LoopInfo after fully unrolling an outer loop.
The loop tree's inclusive block lists are painful and expensive to
update. (I have no idea why they're inclusive). The design was
supposed to handle this case but the implementation missed it and my
unit tests weren't thorough enough.

Fixes PR11335: loop unroll update.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@144970 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-18 03:42:41 +00:00
Andrew Trick
dc07321164 -unroll-scev flag removal
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139010 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-02 17:36:14 +00:00
Andrew Trick
30039de2e9 A slew of unit tests for the recent LoopInfo::updateUnloop feature
checked in at r137276 and r137341.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137385 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-11 23:38:09 +00:00