It looks like this isn't necessary (in any tests I've done, it results
in the global being described with no location or value in the imported
side - while it's still fully described in the place it's imported from)
& results in significant/pathological debug info growth to home these
location-less global variable descriptions on the import side.
This is a rather pressing/important issue to address - this regressed
executable size for one example I'm looking at by 15%, object size is probably
similar though I haven't measured it, and a 22x increase in the number of CUs
in the cu_index in split DWARF DWP files, creating a similarly large regression
in the time it takes llvm-symbolizer to run on such binaries.
Reviewers: tejohnson, evgeny777
Differential Revision: https://reviews.llvm.org/D55309
llvm-svn: 348416
Summary:
Follow up to D49362 ([ThinLTO] Internalize read only globals). Add a
statistic on the number of read only variables (only counting live
variables since dead variables will be dropped anyway).
Reviewers: evgeny777
Subscribers: mehdi_amini, inglorion, eraman, steven_wu, dexonsmith, arphaman, llvm-commits
Differential Revision: https://reviews.llvm.org/D54642
llvm-svn: 347145
An attempt to recommit r346584 after failure on OSX build bot.
Fixed cache key computation in ThinLTOCodeGenerator and added
test case
llvm-svn: 347033
This patch allows internalising globals if all accesses to them
(from live functions) are from non-volatile load instructions
Differential revision: https://reviews.llvm.org/D49362
llvm-svn: 346584
Amy Huang