It is private to llvm. Instead use llvm/Config/llvm-config.h and check
LLVM_ON_UNIX. That is the same guard that clang uses before including
unistd.h.
llvm-svn: 318558
Now that our support for PDB emission is reasonably good, there is
no longer a need to emit a COFF symbol table.
Also fix a bug where we would fail to emit a string table for long
section names if /debug was not specified.
Differential Revision: https://reviews.llvm.org/D40189
llvm-svn: 318548
Summary:
Many small functions have identical unwind info because they push the
same sets of CSRs in the same order and have the same stack and prologue
size. The VC linker merges duplicate .xdata, and so should LLD.
This reduces the .xdata section size of clang.exe from 1.8MB to 94KB.
Reviewers: pcc, ruiu
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D40160
llvm-svn: 318547
This linker backend is still a work in progress but is
enough to link simple programs including linking against
library archives.
Differential Revision: https://reviews.llvm.org/D34851
llvm-svn: 318539
Recently we teached LLD to report line numbers for duplicate variables
definitions, though currently LLD is unable to do that for case when
strings are not built in .debug_info, but stored in .debug_str instead.
That is because out LLDDwarfObj does not handle .debug_str yet.
Patch fixes that.
Differential revision: https://reviews.llvm.org/D39542
llvm-svn: 318519
This fixes PR35223.
Here I enabled SHF_MERGE section content merging for -r like
we do for regular linking.
Differential revision: https://reviews.llvm.org/D40026
llvm-svn: 318516
Commit r318397 fixed the cache pruning interval which broke this test
as it was assuming that the cache pruning was always being
performed. Explicitly set prune interval to 0s to ensure this.
llvm-svn: 318426
Previously our relocations we rewrote were broken for that case.
We emited incorrect addend and broken relocation info field
because did not produce section symbol for mergeable synthetic sections.
Differential revision: https://reviews.llvm.org/D40070
llvm-svn: 318394
Sections that will be mapped at runtime will only have the short
section name available, since the string table it points into isn't
mapped. Therefore prefer truncating those names over writing a
long name that is unavailable at runtime.
This allows libunwind to find the .eh_frame section at runtime even
if the module was built with debug info enabled.
Differential Revision: https://reviews.llvm.org/D40025
llvm-svn: 318391
If -opt:noref is specified, they can end up with isLive() == 1
when the autoexport check is run.
To reduce the risk of potential issues, only consider exporting
DefinedRegular and DefinedCommon, nothing else.
Differential Revision: https://reviews.llvm.org/D40014
llvm-svn: 318384
Summary:
We previously assumed that all SafeSEH handlers are
DefinedRegular symbols. This is not the case for handlers defined in
DLLs. As a result, we were failing to emit entries in the SafeSEH
table for those handlers. This change fixes that.
Fixes PR35324.
Reviewers: rnk, ruiu
Reviewed By: rnk
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D40102
llvm-svn: 318364
An output section can include elements from two input sections with
different sh_entsize. When that happens the output section itself
should not have a sh_entsize.
llvm-svn: 318311
No difference in practice other than having sh_entsize in the output.
This should simplify the patch for handling SHF_MERGE in -r.
Based on a patch by George Rimar.
llvm-svn: 318306
LLD already writes a build id if debug info is enabled.
Some projects set --pie-executable to avoid GNU ld bugs about stripping
base relocations from an executable when they actually are used.
Since -fixed:no is the default (and we don't support setting the
-fixed option via the MinGW frontend), we don't need to handle this.
--disable-auto-image-base is ignored just like --enable-auto-image-base
(as we ignore from before).
Differential Revision: https://reviews.llvm.org/D40031
llvm-svn: 318285
Even if we don't actually write any string table contents, the
4 byte size for the string table will always be written. Make
sure we accommodate for this in the file size. Since this size
is aligned up, this would seldom be an issue in practice.
Differential Revision: https://reviews.llvm.org/D39891
llvm-svn: 318284
GNU ld doesn't seem to support --icf at all, but this was suggested
in D39885, and GNU gold seems to support it.
Differential Revision: https://reviews.llvm.org/D40019
llvm-svn: 318283
All of these are disabled by default in GNU ld, but enabled by default
in lld.
Disable dynamicbase by default since it potentially could cause
compatibility issues, but just ignore the others since the lld
default should be fine for most concievable cases.
Differential Revision: https://reviews.llvm.org/D40017
llvm-svn: 318281
In GNU ld, this option is only available on i386, not on x86_64
(where it's enabled by default with no option to disable it either).
Differential Revision: https://reviews.llvm.org/D40015
llvm-svn: 318280
Lnt is both a server and a set of script for benchmarking llvm.
I don't think it makes sense to use the scripts for lld since our
benchmarks are quite different.
The server on the other hand is very general and seems to work well
for tracking any quantities.
This patch adds a script to lld that can be used to run various
benchmarks and send the result to lnt.
The benchmarks are assumed to each be a response file in a
subdirectory. Each subdirectory can contain multiple response
files. That can be used to have a plain response.txt and a
response-icf.txt for example. The name of each benchmark is the
combination of the directory name and the "flavor": firefox-gc,
chromium-icf, etc.
For the first version the script uses perf and collects all the
metrics that a plain "perf stat" prints.
This script can then be used by a developer to test a patch or by a
bot to keep track of lld's performance.
llvm-svn: 318158
microMIPS symbols including microMIPS PLT records created for regular
symbols needs to be marked by STO_MIPS_MICROMIPS flag in a symbol table.
Additionally microMIPS entries in a dynamic symbol table should have
configured less-significant bit. That allows to escape teaching a
dynamic linker about microMIPS symbols.
llvm-svn: 318097
For GC roots, add a bit to SymbolBody to ensure that we don't add the
same root twice, and switch to a vector. In addition to being faster,
this may also fix some latent non-determinism. We iterate the GCRoot
list later and it the order should be deterministic.
For fixupExports, we can just use DenseMap. This is a simple string
uniquing task, and we don't iterate the map.
Reviewers: ruiu
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39609
llvm-svn: 318072
ICF and GC impair debugging, so MSVC disables these optimizations when
/debug is passed. They are still on by default when no PDB is produced.
This change also makes /opt:ref enable ICF, which is consistent with
MSVC: https://msdn.microsoft.com/en-us/library/bxwfs976.aspx
We should consider making /opt:icf fold readonly data in the near
future. LLD used to do this, but we disabled it because it breaks too
many programs. MSVC only does this if the user explicitly passes
/opt:icf.
Reviewers: ruiu, pcc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39885
llvm-svn: 318071
It is really hard to cover restarts in a debugger, SIGKILL or power
failures. I will try to handle them in a followup patch, but it will
not support all the systems lld has to run on.
RemoveFileOnSignal takes care of crashes.
So what is left is making sure all regular exits delete the file. This
patch does that by moving the buffer to error handling. That is a bit
of a hack, but seemed better than to generalize it to take a callback on
construction.
I will implement this on COFF on the next patch.
llvm-svn: 318060
I never ran into this until lld-link started enabling debug output
by default for the mingw mode. I haven't been able to verify that
this actually behaves correctly, but this relocation is handled
identically on all other architectures so far.
Differential Revision: https://reviews.llvm.org/D39754
llvm-svn: 317669
I think the constract of this function is to remove a file in some way,
whether in background or in foreground. This patch makes sure that it
removes a given file.
Differential Revision: https://reviews.llvm.org/D39778
llvm-svn: 317663
Summary:
__safe_se_handler_base should be either absolute 0 (when no SafeSEH
table is present), or relative to the image base (when the table is
present). An earlier change inadvertedly made the symbol absolute in
both cases, leading to the SafeSEH table not being locatble at run
time. This change fixes that and updates the safeseh test to check for
the presence of the relocation.
Reviewers: rnk, ruiu
Reviewed By: ruiu
Subscribers: ruiu, llvm-commits
Differential Revision: https://reviews.llvm.org/D39765
llvm-svn: 317635
Rafael Espindola