[PATCH] D54411: [Codegen] Merge tail blocks with no successors after block placement

Sun Dec 2 12:06:23 PST 2018

dmgreen added reviewers: craig.topper, rnk, RKSimon.
dmgreen added a comment.

I ran a few bootstraps to check compile time (on AArch64). It didn't seem to make any noticable difference there, and this certainly looks like its good for codesize.

Adding some people who may know about x86 tests (which look fine to me, but I'm no expert)

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Comment at: test/CodeGen/X86/loop-search.ll:25
+; CHECK-NEXT:    jl LBB0_2
 ;            ### FIXME: %bb.3 and LBB0_1 should be merged
+; CHECK-NEXT:  LBB0_5:
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Looks like this comment can be removed now

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Comment at: test/CodeGen/X86/tail-opts.ll:439
+  %1 = icmp eq i32 undef, 0
+  br i1 %1, label %return, label %bb12

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Can you explain this change? The comment makes it look like it should be the same test as above.

But it somehow has different fall-through branches with the switches?

Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D54411/new/

https://reviews.llvm.org/D54411