[PATCH] Implement ADRP CSE for global symbols

[Jiangning Liu]

================
Comment at: test/CodeGen/AArch64/global_merge_2.ll:1
@@ +1,2 @@
+; RUN: llc < %s -mtriple=aarch64-none-linux-gnu -global-merge-on-external=true | FileCheck %s
+
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Tim Northover wrote:
> And speaking of tests, perhaps this would be a good time to promote GlobalMerge to something that can be run through opt and use that to do the testing.
Tim, Do you mean we should move it out of PreISel stage and hoist it to middle end which can really be covered by opt? If yes, do you have any suggestions, where we should drop this pass? I mean, which passes should be before/after this global merge pass? Anyway, I can investigate it myself, and I thought it was designed in PreISel on purpose, although I don't know the reason yet.


http://reviews.llvm.org/D3432