[PATCH] D71025: [LoopFusion] Restrict loop fusion to rotated loops.

[Kit Barton via Phabricator via llvm-commits]

kbarton marked 4 inline comments as done.
kbarton added a comment.

Addressed all the review comments. 
I'm ready to land this, unless @Whitney has concerns about the test case.



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Comment at: llvm/test/Transforms/LoopFusion/cannot_fuse.ll:42
+bb34:
+  %cmp = icmp slt i32 %N, 50
+  br i1 %cmp, label %bb16, label %bb33
----------------
Whitney wrote:
> This guard was not in the original test case, now the second loop has two guards, is that intensional?                    
Yes, this is intentional to make the two loops not control-flow-equivalent, which is what this specific test is checking. 


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Comment at: llvm/test/Transforms/LoopFusion/cannot_fuse.ll:270
 ; CHECK-NEXT: [[LOOP2PREHEADER]]
-; CHECK: Memory dependencies do not allow fusion!
+; CHECK: Fusion candidate does not have empty preheader. Not fusing.
 ; CHECK: Loop Fusion complete
----------------
Meinersbur wrote:
> Does this test something different now?
This is a good catch. I missed this. I've fixed it to check for the memory dependencies again. 


Repository:
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  https://reviews.llvm.org/D71025/new/

https://reviews.llvm.org/D71025