I think code is dead, because the only way to see
Path as empty seems would be if replaceThinLTOSuffix()
replaced some prefix with empty prefix (making the result
Path empty).
But it is impossible to pass the empty prefix,
we would file in driver:
https://github.com/llvm-mirror/lld/blob/master/ELF/Driver.cpp#L669
llvm-svn: 336338
- Move some common code into Common/rrorHandler.cpp and
Common/Strings.h.
- Don't use `fatal` when incompatible bitcode files are
encountered.
- Rename NameRef variable to just Name
See D47162
Differential Revision: https://reviews.llvm.org/D47206
llvm-svn: 333021
Instead of writing empty index for file, this patch tracks the state of files in ObjectToIndexFileState. If the files are not indexed , only then we emit the empty files
Differential Revision: https://reviews.llvm.org/D46480
llvm-svn: 331803
Previously, code to initialize Backend and code to initialize Conf are
intermingled in init(), though they don't depend on each other.
Differential Revision: https://reviews.llvm.org/D46554
llvm-svn: 331698
Our promise is that as long as there's no fatal error (i.e. broken
file is given to the linker), our main function returns to the caller.
So we can't use exit() in the regular code path.
Differential Revision: https://reviews.llvm.org/D46442
llvm-svn: 331690
Summary:
With D43396, no clients use the Path parameter anymore.
This is the lld side fix with D43400.
Depends on D43396 and D43400.
Reviewers: pcc
Subscribers: emaste, inglorion, arichardson, llvm-commits
Differential Revision: https://reviews.llvm.org/D43401
llvm-svn: 325620
objects, it confuses codegen into generating pc-rel relocations for those
symbols, which leads to linker errors.
Differential Revision: https://reviews.llvm.org/D42977
llvm-svn: 324435
Previously an empty CPU string was passed to the LTO engine which
resulted in a generic CPU for which certain features like NOPL were
disabled. This fixes that.
Patch by Pratik Bhatu!
llvm-svn: 323801
Currently symbols assigned or created by linkerscript are not processed early
enough. As a result it is not possible to version them or assign any other flags/properties.
Patch creates Defined symbols for -defsym and linkerscript symbols early,
so that issue from above can be addressed.
It is based on Rafael Espindola's version of D38239 patch.
Fixes PR34121.
Differential revision: https://reviews.llvm.org/D41987
llvm-svn: 323729
We track both the combined visibility that will be used for the output
symbol and the original input visibility of the selected symbol.
Almost everything should use the computed visibility.
I will make the names less confusing an a followup patch.
llvm-svn: 322576
Now that we have only SymbolBody as the symbol class. So, "SymbolBody"
is a bit strange name now. This is a mechanical change generated by
perl -i -pe s/SymbolBody/Symbol/g $(git grep -l SymbolBody lld/ELF lld/COFF)
nd clang-format-diff.
Differential Revision: https://reviews.llvm.org/D39459
llvm-svn: 317370
SymbolBody and Symbol were separated classes due to a historical reason.
Symbol used to be a pointer to a SymbolBody, and the relationship
between Symbol and SymbolBody was n:1.
r2681780 changed that. Since that patch, SymbolBody and Symbol are
allocated next to each other to improve memory locality, and they have
1:1 relationship now. So, the separation of Symbol and SymbolBody no
longer makes sense.
This patch merges them into one class. In order to avoid updating too
many places, I chose SymbolBody as a unified name. I'll rename it Symbol
in a follow-up patch.
Differential Revision: https://reviews.llvm.org/D39406
llvm-svn: 317006
Summary:
The COFF linker and the ELF linker have long had similar but separate
Error.h and Error.cpp files to implement error handling. This change
introduces new error handling code in Common/ErrorHandler.h, changes the
COFF and ELF linkers to use it, and removes the old, separate
implementations.
Reviewers: ruiu
Reviewed By: ruiu
Subscribers: smeenai, jyknight, emaste, sdardis, nemanjai, nhaehnle, mgorny, javed.absar, kbarton, fedor.sergeev, llvm-commits
Differential Revision: https://reviews.llvm.org/D39259
llvm-svn: 316624
"Commands" was ambiguous because in the linker script, everything is
a command. We used to handle only SECTIONS commands, and at the time,
it might make sense to call them the commands, but it is no longer
the case. We handle not only SECTIONS but also MEMORY, PHDRS, VERSION,
etc., and they are all commands.
llvm-svn: 315409
ScriptConfiguration was a class to contain parsed results of
linker scripts. LinkerScript is a class to interpret it.
That ditinction was needed because we haven't instantiated
LinkerScript early (because, IIRC, LinkerScript class was a
ELFT template function). So, when we parse linker scripts,
we couldn't directly store the result to a LinkerScript instance.
Now, that limitation is gone. We instantiate LinkerScript
at the very beginning of our main function. We can directly
store parse results to a LinkerScript instance.
llvm-svn: 315403
New lld's files are spread under lib subdirectory, and it isn't easy
to find which files are actually maintained. This patch moves maintained
files to Common subdirectory.
Differential Revision: https://reviews.llvm.org/D37645
llvm-svn: 314719
Previously when BC file had global variable that was accessed from script,
it was optimized away or inlined by IPO.
In this patch I add symbols at left side of assignment expression as LinkerRedefined,
what prevents optimization for them.
Differential revision: https://reviews.llvm.org/D37059
llvm-svn: 314097
In order to keep track of symbol renaming, we used to have
Config->SymbolRenaming, and whether a symbol is in the map or not
affects its symbol attribute (i.e. "LinkeRedefined" bit).
This patch adds "CanInline" bit to Symbol to aggreagate symbol
information in one place and removed the member from Config since
no one except SymbolTable now uses the table.
llvm-svn: 314088
This is PR33097.
Previously when doing relocatable link, all IR symbols were absent
in result object file. Patch makes external symbols to be exported.
Differential revision: https://reviews.llvm.org/D36957
llvm-svn: 311431
With this Symbol has the same size as before, but DefinedRegular goes
from 72 to 64 bytes.
I also find this a bit easier to read. There are fewer places
initializing File for example.
This has a small but measurable speed improvement on all tests (1%
max).
llvm-svn: 310142
Reviewing another change I noticed that we use "getSymbols" to mean
different things in different files. Depending on the file it can
return
ArrayRef<StringRef>
ArrayRef<SymbolBody*>
ArrayRef<Symbol*>
ArrayRef<Elf_Sym>
With this change it always returns an ArrayRef<SymbolBody*>. The other
functions are renamed getELFsyms() and getSymbolNames().
Note that we cannot return ArrayRef<Symbol*> instead of
ArreyRef<SymbolBody*> because local symbols have a SymbolBody but not
a Symbol.
llvm-svn: 309840
With this we only ask LTO to keep a C named section if there is a
__start_ or __end symbol.
This is not as strict as lld's --gc-sections, but is as good as we can
get without having a far more detailed ir summary.
llvm-svn: 309232
We do this emitting a section for every function when LTO is used.
Fixes PR33888.
Differential Revision: https://reviews.llvm.org/D35809
llvm-svn: 308915
This creates a new library called BinaryFormat that has all of
the headers from llvm/Support containing structure and layout
definitions for various types of binary formats like dwarf, coff,
elf, etc as well as the code for identifying a file from its
magic.
Differential Revision: https://reviews.llvm.org/D33843
llvm-svn: 304864
procedural optimizations to prevent dropping symbols and allow the linker
to process re-directs.
PR33145: --wrap doesn't work with lto.
Differential Revision: https://reviews.llvm.org/D33621
llvm-svn: 304719
It doesn't matter what binding we store in a non-UsedInRegularObj undefined
symbol because we should reset it when we see a real undefined symbol in
a combined LTO object. The fact that we weren't doing so before is a bug
(PR32899) which is now fixed.
llvm-svn: 302067
If there is a bug in the LTO implementation that causes it to fail to provide
an expected symbol definition, the linker should report an undefined symbol
error. Unfortunately, we were failing to do so if the symbol definition
was weak, as the undefine() function was turning the definition into a weak
undefined symbol, which resolves to zero if the symbol remains undefined. This
patch causes us to set the binding to STB_GLOBAL when we undefine a symbol.
I can't see a good way to test this. The behaviour should only be observable
if there is a bug in the LTO implementation.
Differential Revision: https://reviews.llvm.org/D32731
llvm-svn: 301897
We had a few Config member functions that returns configuration values.
For example, we had is64() which returns true if the target is 64-bit.
The return values of these functions are constant and never change.
This patch is to compute them only once to make it clear that they'll
never change.
llvm-svn: 298168
This patch causes us to use pruneCache() to prune the ThinLTO cache after
completing LTO. A new flag --thinlto-cache-policy allows users to configure
the policy.
Differential Revision: https://reviews.llvm.org/D31021
llvm-svn: 298036
After the call to sys::fs::exists succeeds, indicating a cache hit, we call
AddFile and the client will open the file using the supplied path. If the
client is using cache pruning, there is a potential race between the pruner
and the client. To avoid this, change the caching API so that it provides
a MemoryBuffer to the client, and have clients use that MemoryBuffer where
possible.
This scheme won't work with the gold plugin because the plugin API expects a
file path. So we have the gold plugin use the buffer identifier as a path and
live with the race for now. (Note that the gold plugin isn't actually affected
by the problem at the moment because it doesn't support cache pruning.)
This effectively reverts r279883 modulo the change to use the existing path
in the gold plugin.
Differential Revision: https://reviews.llvm.org/D31063
llvm-svn: 298020
This patch adds an option named --thinlto-cache-dir, which specifies the
path to a directory in which to cache native object files for ThinLTO
incremental builds.
Differential Revision: https://reviews.llvm.org/D30509
llvm-svn: 296702
Summary: llvm/CodeGen/CommandFlags.h a utility function InitTargetOptionsFromCodeGenFlags which is used to set target options from flags based on the command line. The command line flags are stored in globals defined in the same file, and including the file in multiple places causes the globals to be defined multiple times, leading to linker errors. This change adds a single place in lld where these globals are defined and exports only the utility function. This makes it possible to call InitTargetOptionsFromCodeGenFlags from multiple places in lld, which a follow-up change will do.
Reviewers: davide, ruiu
Reviewed By: davide, ruiu
Subscribers: mgorny
Differential Revision: https://reviews.llvm.org/D29058
llvm-svn: 293965
Thunks are now implemented by redirecting the relocation to the
symbol S, to a symbol TS in a Thunk. The Thunk will transfer control
to S. This has the following implications:
- All the side-effects of Thunks happen within createThunks()
- Thunks are no longer stored in InputSections and Symbols no longer
need to hold a pointer to a Thunk
- The synthetic Thunk sections need to be merged into OutputSections
This implementation is almost a direct conversion of the existing
Thunks with the following exceptions:
- Mips LA25 Thunks are placed before the InputSection that defines
the symbol that needs a Thunk.
- All ARM Thunks are placed at the end of the OutputSection of the
first caller to the Thunk.
Range extension Thunks are not supported yet so it is optimistically
assumed that all Thunks can be reused.
This is a recommit of r293283 with a fixed comparison predicate as
std::merge requires a strict weak ordering.
Differential revision: https://reviews.llvm.org/D29327
llvm-svn: 293757
Thunks are now implemented by redirecting the relocation to the
symbol S, to a symbol TS in a Thunk. The Thunk will transfer control
to S. This has the following implications:
- All the side-effects of Thunks happen within createThunks()
- Thunks are no longer stored in InputSections and Symbols no longer
need to hold a pointer to a Thunk
- The synthetic Thunk sections need to be merged into OutputSections
This implementation is almost a direct conversion of the existing
Thunks with the following exceptions:
- Mips LA25 Thunks are placed before the InputSection that defines
the symbol that needs a Thunk.
- All ARM Thunks are placed at the end of the OutputSection of the
first caller to the Thunk.
Range extension Thunks are not supported yet so it is optimistically
assumed that all Thunks can be reused.
Differential Revision: https://reviews.llvm.org/D29129
llvm-svn: 293283
In a shared library an undefined symbol is implicitly imported. If the
symbol is called as a function a PLT entry is generated for it. When the
caller is a Thumb b.w a thunk to the PLT entry is needed as all PLT
entries are in ARM state.
This change allows undefined symbols to have thunks in the same way that
shared symbols may have thunks.
llvm-svn: 290951
StringRefZ is a class to represent a null-terminated string. String
length is computed lazily, so it's more efficient than StringRef to
represent strings in string table.
The motivation of defining this new class is to merge functions
that only differ in string types; we have many constructors that takes
`const char *` or `StringRef`. With StringRefZ, we can merge them.
Differential Revision: https://reviews.llvm.org/D27037
llvm-svn: 288172
Now that lld switched to lib/LTO, which always calls setDataLayout(),
we don't need this check anymore.
Thanks to Peter for pointing out!
llvm-svn: 287699
Previously, we do this piece of code to iterate over all input sections.
for (elf::ObjectFile<ELFT> *F : Symtab.getObjectFiles())
for (InputSectionBase<ELFT> *S : F->getSections())
It turned out that this mechanisms doesn't work well with synthetic
input sections because synthetic input sections don't belong to any
input file.
This patch defines a vector that contains all input sections including
synthetic ones.
llvm-svn: 286051
Previously, we have a lot of BumpPtrAllocators, but all these
allocators virtually have the same lifetime because they are
not freed until the linker finishes its job. This patch aggregates
them into a single allocator.
Differential revision: https://reviews.llvm.org/D26042
llvm-svn: 285452
We used to have one allocator per file, which reduces the advantage of
using an allocator in the first place.
This is a small speed up is most cases. The largest speedup was in
1.014X in chromium no-gc. The largest slowdown was scylla at 1.003X.
llvm-svn: 285205
Before the default was whatever number hardware_concurrency() returned.
Users can specify the number of threads via --lto-jobs=X option.
llvm-svn: 283787
We have a few "check" functions in Error.h. All of them are to
check for an error and strip an error object if there was no error,
except "void check(Error E)", which doesn't return anything.
This patch renames it and moves it to the .cpp file where it is used.
llvm-svn: 282764
I found out this wasn't tested when looking at Vedant's coverage bot
numbers, so, thanks to him. While I'm here, switch the error message
to be lld-compliant (first letter lowercase).
llvm-svn: 282335
Previously, all input files were owned by the symbol table.
Files were created at various places, such as the Driver, the lazy
symbols, or the bitcode compiler, and the ownership of new files
was transferred to the symbol table using std::unique_ptr.
All input files were then free'd when the symbol table is freed
which is on program exit.
I think we don't have to transfer ownership just to free all
instance at once on exit.
In this patch, all instances are automatically collected to a
vector and freed on exit. In this way, we no longer have to
use std::unique_ptr.
Differential Revision: https://reviews.llvm.org/D24493
llvm-svn: 281425
Before this lld was always creating common symbols itself. It worked,
but prevented them from being internalized when possible.
Now it preserves common symbols is the bitcode and they are internalized.
Fixes pr30184.
llvm-svn: 280242
Previously, each subclass of SymbolBody had a pointer to a source
file from which it was created. So, there was no single way to get
a source file for a symbol. We had getSourceFile<ELFT>(), but the
function was a bit inconvenient as it's a template.
This patch makes SymbolBody have a pointer to a source file.
If a symbol is not created from a file, the pointer has a nullptr.
llvm-svn: 275701
George Rimar