Commit Graph

6 Commits

Author SHA1 Message Date
Teresa Johnson 290a839891 [LTO] Record whether LTOUnit splitting is enabled in index
Summary:
Records in the module summary index whether the bitcode was compiled
with the option necessary to enable splitting the LTO unit
(e.g. -fsanitize=cfi, -fwhole-program-vtables, or -fsplit-lto-unit).

The information is passed down to the ModuleSummaryIndex builder via a
new module flag "EnableSplitLTOUnit", which is propagated onto a flag
on the summary index.

This is then used during the LTO link to check whether all linked
summaries were built with the same value of this flag. If not, an error
is issued when we detect a situation requiring whole program visibility
of the class hierarchy. This is the case when both of the following
conditions are met:
1) We are performing LowerTypeTests or Whole Program Devirtualization.
2) There are type tests or type checked loads in the code.

Note I have also changed the ThinLTOBitcodeWriter to also gate the
module splitting on the value of this flag.

Reviewers: pcc

Subscribers: ormris, mehdi_amini, Prazek, inglorion, eraman, steven_wu, dexonsmith, arphaman, dang, llvm-commits

Differential Revision: https://reviews.llvm.org/D53890

llvm-svn: 350948
2019-01-11 18:31:57 +00:00
Eugene Leviant bf46e7410c [ThinLTO] Internalize readonly globals
An attempt to recommit r346584 after failure on OSX build bot.
Fixed cache key computation in ThinLTOCodeGenerator and added
test case

llvm-svn: 347033
2018-11-16 07:08:00 +00:00
Steven Wu fa43892d6f Revert "[ThinLTO] Internalize readonly globals"
This reverts commit 10c84a8f35cae4a9fc421648d9608fccda3925f2.

llvm-svn: 346768
2018-11-13 17:35:04 +00:00
Eugene Leviant be8d19967a [ThinLTO] Internalize readonly globals
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
2018-11-10 08:31:21 +00:00
Volodymyr Sapsai 8b46ff1648 [ThinLTO] Remove too aggressive assertion in building function call graph.
The assertion was introduced in r317853 but there are cases when a call
isn't handled either as direct or indirect. In this case we add a
reference graph edge but not a call graph edge.

Reviewers: tejohnson

Reviewed By: tejohnson

Subscribers: mehdi_amini, inglorion, eraman, hiraditya, efriedma, llvm-commits

Differential Revision: https://reviews.llvm.org/D40056

llvm-svn: 318540
2017-11-17 18:28:05 +00:00
Volodymyr Sapsai a73960213e [ThinLTO] Fix missing call graph edges for calls with bitcasts.
This change doesn't fix the root cause of the miscompile PR34966 as the root
cause is in the linker ld64. This change makes call graph more complete
allowing to have better module imports/exports.

rdar://problem/35344706

Reviewers: tejohnson

Reviewed By: tejohnson

Subscribers: mehdi_amini, inglorion, eraman, llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D39356

llvm-svn: 317853
2017-11-10 00:47:47 +00:00