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
Should fix bot failures due to r291108 which happened due to a
change required in ModuleSummaryIndexYAML.h which was just added in
r291069.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291111 91177308-0d34-0410-b5e6-96231b3b80d8
Set up basic YAML I/O support for module summaries, plumb the summary into
the pass and add a few command line flags to test YAML I/O support. Bitcode
support to come separately, as will the code in LowerTypeTests that actually
uses the summary. Also add a couple of tests that pass by virtue of the pass
doing nothing with the summary (which happens to be the correct thing to do
for those tests).
Differential Revision: https://reviews.llvm.org/D28041
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291069 91177308-0d34-0410-b5e6-96231b3b80d8
