[llvm] r277901 - Revert "[LoopSimplify] Fix updating LCSSA after separating nested loops."

[Michael Zolotukhin via llvm-commits]

Author: mzolotukhin
Date: Fri Aug  5 20:48:51 2016
New Revision: 277901

URL: http://llvm.org/viewvc/llvm-project?rev=277901&view=rev
Log:
Revert "[LoopSimplify] Fix updating LCSSA after separating nested loops."

This reverts commit r277877.
Try to appease clang-x64-ninja-win7 buildbot.

Modified:
    llvm/trunk/lib/Transforms/Utils/LoopSimplify.cpp
    llvm/trunk/test/Transforms/LoopSimplify/pr28272.ll

Modified: llvm/trunk/lib/Transforms/Utils/LoopSimplify.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Utils/LoopSimplify.cpp?rev=277901&r1=277900&r2=277901&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Utils/LoopSimplify.cpp (original)
+++ llvm/trunk/lib/Transforms/Utils/LoopSimplify.cpp Fri Aug  5 20:48:51 2016
@@ -376,21 +376,6 @@ static Loop *separateNestedLoop(Loop *L,
         }
       }
     }
-    // We also need to check exit blocks of the outer loop - it might be using
-    // values from what now became an inner loop.
-    SmallVector<BasicBlock*, 8> ExitBlocks;
-    NewOuter->getExitBlocks(ExitBlocks);
-    for (BasicBlock *ExitBB: ExitBlocks) {
-      for (Instruction &I : *ExitBB) {
-        for (Value *Op : I.operands()) {
-          Instruction *OpI = dyn_cast<Instruction>(Op);
-          if (!OpI || !L->contains(OpI))
-            continue;
-          WorklistSet.insert(OpI);
-        }
-      }
-    }
-
     SmallVector<Instruction *, 8> Worklist(WorklistSet.begin(),
                                            WorklistSet.end());
     formLCSSAForInstructions(Worklist, *DT, *LI);

Modified: llvm/trunk/test/Transforms/LoopSimplify/pr28272.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/LoopSimplify/pr28272.ll?rev=277901&r1=277900&r2=277901&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/LoopSimplify/pr28272.ll (original)
+++ llvm/trunk/test/Transforms/LoopSimplify/pr28272.ll Fri Aug  5 20:48:51 2016
@@ -1,7 +1,7 @@
 ; RUN: opt < %s -lcssa -loop-unroll -S | FileCheck %s
 target triple = "x86_64-unknown-linux-gnu"
 
-; PR28272, PR28825
+; PR28272
 ; When LoopSimplify separates nested loops, it might break LCSSA form: values
 ; from the original loop might be used in the outer loop. This test invokes
 ; loop-unroll, which calls loop-simplify before itself. If LCSSA is broken
@@ -74,35 +74,3 @@ loop2.if.false:
 bb:
   br label %loop2
 }
-
-; When LoopSimplify separates nested loops, it might break LCSSA form: values
-; from the original loop might be used in exit blocks of the outer loop.
-; CHECK-LABEL: @foo3
-define void @foo3() {
-entry:
-  br label %bb1
-
-bb1:
-  br i1 undef, label %bb2, label %bb1
-
-bb2:
-  %a = phi i32 [ undef, %bb1 ], [ %a, %bb3 ], [ undef, %bb5 ]
-  br i1 undef, label %bb3, label %bb1
-
-bb3:
-  %b = load i32*, i32** undef
-  br i1 undef, label %bb2, label %bb4
-
-bb4:
-  br i1 undef, label %bb5, label %bb6
-
-bb5:
-  br i1 undef, label %bb2, label %bb4
-
-bb6:
-  br i1 undef, label %bb_end, label %bb1
-
-bb_end:
-  %x = getelementptr i32, i32* %b
-  br label %bb_end
-}