[PATCH] Implement ADRP CSE for global symbols

[Quentin Colombet]

Hi Jiangning,

I've stopped the benchmarking because I am seeing compiler crashes, with the current patch, when the merge on external is enabled:
Assertion failed: (Globals[i]->hasExternalLinkage() == IsExternal), function doMerge, file lib/Transforms/Scalar/GlobalMerge.cpp, line 199.

The following tests do not compile:
External/SPEC/CINT2000/255.vortex/255.vortex
External/SPEC/CINT2006/445.gobmk/445.gobmk
External/SPEC/CINT95/147.vortex/147.vortex
MultiSource/Applications/oggenc/oggenc
MultiSource/Benchmarks/MiBench/consumer-lame/consumer-lame

I am attaching the reduced test case from 445.gobmk. {F57098}
To reproduce:
llc  -global-merge-on-external=true  reduced_testcase.ll

Could you have a look please?

As soon as this is fixed, I can start over the benchmarking.

Thanks,

Quentin

http://reviews.llvm.org/D3432