Previously, we have re-implemented utility functions such as `expect`
or `next` in LinkerScript.cpp. This patch reuses the existing
implementation that is in ScriptParser.cpp.
llvm-svn: 267255
ScriptParserBase class is a container of collection of various methods
to parse linker script-ish text. It had a virtual method `run` to run
the parser. But we don't have to enforce its descendents to implement
that. It's up to them.
This patch removes pure virtual function `run`.
llvm-svn: 267246
The fix is to handle local symbols referring to SHF_MERGE sections.
Original message:
GC entries of SHF_MERGE sections.
It is a fairly direct extension of the gc algorithm. For merge sections
instead of remembering just a live bit, we remember which offsets
were used.
This reduces the .rodata sections in chromium from 9648861 to 9477472
bytes.
llvm-svn: 267233
This patch is to remove -lto-no-discard-value-names flag and
instead to use -save-temps as we discussed in the post-commit
review thread for r267020.
Differential Revision: http://reviews.llvm.org/D19437
llvm-svn: 267230
This patch only implements support for version scripts of the form:
{ [ global: symbol1; symbol2; [...]; symbolN; ] local: *; };
No wildcards are supported, other than for the local entry. Symbol versioning
is also not supported.
It works by introducing a new Symbol flag which tracks whether a symbol
appears in the global section of a version script.
This patch also simplifies the logic in SymbolBody::isPreemptible(), and
teaches it to handle the case where symbols with default visibility in DSOs
do not appear in the dynamic symbol table because of a version script.
Fixes PR27482.
Differential Revision: http://reviews.llvm.org/D19430
llvm-svn: 267208
These are properties of a symbol name, rather than a particular instance
of a symbol in an object file. We can simplify the code by collecting these
properties in Symbol.
The MustBeInDynSym flag has been renamed ExportDynamic, as its semantics
have been changed to be the same as those of --dynamic-list and
--export-dynamic-symbol, which do not cause hidden symbols to be exported.
Differential Revision: http://reviews.llvm.org/D19400
llvm-svn: 267183
It is a fairly direct extension of the gc algorithm. For merge sections
instead of remembering just a live bit, we remember which offsets were
used.
This reduces the .rodata sections in chromium from 9648861 to 9477472
bytes.
llvm-svn: 267164
It turns out that this will read data from the section to properly
handle Elf_Rel implicit addends.
Sorry for the noise.
Original messages:
Try to fix Windows lld build.
Move getRelocTarget to ObjectFile.
It doesn't use anything from the InputSection.
llvm-svn: 267163
llvm\tools\lld\ELF\MarkLive.cpp(49): error C2872: 'ObjectFile': ambiguous symbol
llvm\tools\lld\elf\InputFiles.h(100): note: could be 'lld:🧝:ObjectFile'
llvm\include\llvm/Object/IRObjectFile.h(26): note: or 'llvm::object::ObjectFile'
llvm\tools\lld\ELF\MarkLive.cpp(133): note: see reference to function template instantiation
'void forEachSuccessor<ELFT>(lld:🧝:InputSection<ELFT> *,
std::function<void (lld:🧝:InputSectionBase<ELFT> *)>)'
being compiled with
[ ELFT=llvm::object::ELF32LE ]
llvm\tools\lld\ELF\MarkLive.cpp(136): note: see reference to function template instantiation
'void lld:🧝:markLive<llvm::object::ELF32LE>(lld:🧝:SymbolTable<llvm::object::ELF32LE> *)
being compiled
llvm-svn: 267161
I will eventually make `evaluate` function a usual parse function
rather than a function that works on a separate token list.
This is the first step toward that.
llvm-svn: 267083
You can instruct the linker to not discard sections even if they
are unused and --gc-sections option is given. The linker script
command for doing that is KEEP. The syntax is KEEP(foo) where foo
is a section name. KEEP commands are written in SECTIONS command,
so you can specify the order of sections *and* which sections
will be kept.
Each sub-command in SECTIONS command are translated into SectionRule
object. Previously, each SectionRule has `Keep` bit. However,
if you think about it, this hid information in too deep in elements
of a list. Semantically, KEEP commands aren't really related to
SECTIONS subcommands. We can keep the section list for KEEP in a
separate list. This patch does that.
llvm-svn: 267065
Since there is a copy in every translation unit that uses them, they can
be omitted from the symbol table if the address is not significant.
This still doesn't catch as many cases as the gold plugin. The
difference is that we check canBeOmittedFromSymbolTable in each file and
use lazy loading which limits what it can do. Gold checks it in the merged file.
I think the correct way of getting the same results as gold is just to
cache in the IR the result of canBeOmittedFromSymbolTable.
llvm-svn: 267063
I noticed that I was looking for the definition of SymPair when hacking
the Writer, only to find that it is just a pair of DefinedRegular symbols.
I don't think it provides more values than the cost of using brainpower
to memorize the type. I didn't roll back r266317, which introduced SymPair,
because the patch removes code repetitions. I ported that change to new
code.
llvm-svn: 267047
GNU ld and gold only support the discard-all and discard-locals with two dashes.
Retain the compatibility with the one dash spelling, but also accept the two
dashed form.
llvm-svn: 267032
`--add-needed` and `--no-add-needed` have been deprecated due to the similarity
of their spelling to `--as-needed` and `--no-as-needed`. They have been renamed
to `--copy-dt-needed-entries` and `--no-copy-dt-needed-entries`.
llvm-svn: 267031
Rafael reported on the mailing list that this reduces peak memory
usage while linking llvm-as by 15%. It makes sense to make it
the default, and introduce an inverse knob -lto-no-discard-value-names
for those who want to restore the old behavior.
llvm-svn: 267020
Rui Ueyama