Teresa Johnson a4ca999339 ThinLTO: add early "dead-stripping" on the Index ...

Summary:
Using the linker-supplied list of "preserved" symbols, we can compute
the list of "dead" symbols, i.e. the one that are not reachable from
a "preserved" symbol transitively on the reference graph.
Right now we are using this information to mark these functions as
non-eligible for import.

The impact is two folds:
- Reduction of compile time: we don't import these functions anywhere
  or import the function these symbols are calling.
- The limited number of import/export leads to better internalization.

Patch originally by Mehdi Amini.

Reviewers: mehdi_amini, pcc

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D23488

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291177 91177308-0d34-0410-b5e6-96231b3b80d8

2017-01-05 21:34:18 +00:00

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ThinLTO: add early "dead-stripping" on the Index

2017-01-05 21:34:18 +00:00

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ThinLTO: add early "dead-stripping" on the Index

2017-01-05 21:34:18 +00:00

CMakeLists.txt

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LLVMBuild.txt

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