[PATCH] [Jump-Threading] Fixed jump threading hang issues (PR15386, PR15851)

[Rafael Ávila de Espíndola]

LGTM with two nits.

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Comment at: lib/Transforms/Scalar/JumpThreading.cpp:161
@@ -160,1 +160,3 @@
 
+  removeUnreachableBlocks(F);
+
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Please include a comment saying why this is not just an optimization.

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Comment at: test/Transforms/JumpThreading/pr15851_hang.ll:1
@@ +1,2 @@
+; RUN: timeout 10s opt -S -jump-threading < %s | FileCheck %s
+
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I don't think timeout is portable. Just run opt directly.

http://reviews.llvm.org/D3991