llvm-project/llvm
Duncan P. N. Exon Smith 43ea3478bf LTO: add API to set strategy for -internalize
Add API to LTOCodeGenerator to specify a strategy for the -internalize
pass.

This is a new attempt at Bill's change in r185882, which he reverted in
r188029 due to problems with the gold linker.  This puts the onus on the
linker to decide whether (and what) to internalize.

In particular, running internalize before outputting an object file may
change a 'weak' symbol into an internal one, even though that symbol
could be needed by an external object file --- e.g., with arclite.

This patch enables three strategies:

- LTO_INTERNALIZE_FULL: the default (and the old behaviour).
- LTO_INTERNALIZE_NONE: skip -internalize.
- LTO_INTERNALIZE_HIDDEN: only -internalize symbols with hidden
  visibility.

LTO_INTERNALIZE_FULL should be used when linking an executable.

Outputting an object file (e.g., via ld -r) is more complicated, and
depends on whether hidden symbols should be internalized.  E.g., for
ld -r, LTO_INTERNALIZE_NONE can be used when -keep_private_externs, and
LTO_INTERNALIZE_HIDDEN can be used otherwise.  However,
LTO_INTERNALIZE_FULL is inappropriate, since the output object file will
eventually need to link with others.

lto_codegen_set_internalize_strategy() sets the strategy for subsequent
calls to lto_codegen_write_merged_modules() and lto_codegen_compile*().

<rdar://problem/14334895>

llvm-svn: 199191
2014-01-14 06:37:26 +00:00
..
autoconf Remove the last weird subproject, 'privbracket'. 2014-01-14 05:05:18 +00:00
bindings Makefile.ocaml: Tweak to use --system-libs. 2013-12-20 00:36:59 +00:00
cmake Factor the option and checking of compiler version better. Put the 2014-01-13 22:21:34 +00:00
docs Docs: fix sign of division and increase equivocation on code generated. 2014-01-13 10:47:04 +00:00
examples [cleanup] Re-sort the examples #include lines with my sort_includes 2014-01-13 09:58:03 +00:00
include LTO: add API to set strategy for -internalize 2014-01-14 06:37:26 +00:00
lib LTO: add API to set strategy for -internalize 2014-01-14 06:37:26 +00:00
projects Revert "Revert "Windows: Add support for unicode command lines"" 2013-10-07 01:00:07 +00:00
test Always let value types influence register classes. 2014-01-14 06:18:38 +00:00
tools LTO: add API to set strategy for -internalize 2014-01-14 06:37:26 +00:00
unittests Update getLazyBitcodeModule to use ErrorOr for error handling. 2014-01-13 18:31:04 +00:00
utils AVX-512: Embedded Rounding Control - encoding and printing 2014-01-13 12:55:03 +00:00
.arcconfig
.clang-format Add a clang-format file so that the tool can automatically detect the 2013-09-02 07:19:04 +00:00
.gitignore
CMakeLists.txt Factor the option and checking of compiler version better. Put the 2014-01-13 22:21:34 +00:00
CODE_OWNERS.TXT Update email address. 2013-12-04 09:42:49 +00:00
CREDITS.TXT Fix documentation typos 2013-12-20 00:33:39 +00:00
LICENSE.TXT Update the copyright credits -- Happy new year 2014! 2014-01-01 08:27:31 +00:00
LLVMBuild.txt Remove the very substantial, largely unmaintained legacy PGO 2013-10-02 15:42:23 +00:00
Makefile llvm-config: Fixup r197380, tweak for cross compilation. SYSTEM_LIBS should be --host's in BuildTools/llvm-config. 2013-12-16 13:09:06 +00:00
Makefile.common
Makefile.config.in
Makefile.rules [Mips]Work around MIPS linker issues exposed by commit r198087 until bug 18360 is resolved 2014-01-03 22:18:43 +00:00
README.txt Revert "Test commit to check e-mail address. Please discard this." 2013-10-04 10:59:13 +00:00
configure Remove the last weird subproject, 'privbracket'. 2014-01-14 05:05:18 +00:00
llvm.spec.in

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