llvm/test/ThinLTO/X86/Inputs/deadstrip.ll
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

23 lines
588 B
LLVM

target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-apple-macosx10.11.0"
declare void @dead_func()
; Called from a @dead_func() in the other file, should not be imported there
; Ensure the cycle formed by calling @dead_func doesn't prevent stripping.
define void @baz() {
call void @dead_func()
ret void
}
; Called via llvm.global_ctors, should be detected as live via the
; marking of llvm.global_ctors as a live root in the index.
define void @boo() {
ret void
}
define void @another_dead_func() {
call void @dead_func()
ret void
}