By using an index instead of a pointer for verdef we can put the index
next to the alignment field. This uses the otherwise wasted area and
reduces the shared symbol size.
By itself the performance change of this is in the noise, but I have a
followup patch to remove another 8 bytes that improves performance
when combined with this.
llvm-svn: 320449
An internal linker has support for merging identical data and in some
cases it can be a significant win.
This is behind an off by default flag so it has to be requested
explicitly.
llvm-svn: 320448
When an output section has no byte commands and has no input sections then it
would be ideal if the type of the section is SHT_NOBITS so that the file can
take up less space. This change sets the default type of of output sections to
SHT_NOBITS instead of SHT_PROGBITS to allow this. This required some minor test
changes (which double as tests for this new behavior) but extend-pt-load.s had
be changed in a non-trivial way. Since it seems to me that the point of the
test is to point out the consequences of how flags are assigned to output
sections that don't have input sections I changed the test to work and still
show how the memsize of the executable segment was changed.
Differential Revision: https://reviews.llvm.org/D41082
llvm-svn: 320437
The PPC port doesn't support PLT yet, but the architecture independent
code optimizes PLT access for non preemptible symbols, which is
exactly what returning R_PC was trying to implement.
llvm-svn: 320430
Now that gc sections runs after linker defined symbols are added it
can see symbols that point to an OutputSection.
Should fix a bot failure.
llvm-svn: 320412
This fixes pr35570.
We were creating these symbols after parsing version scripts, so they
could not be versioned.
We cannot move the version script parsing later because we need it for
lto.
One option is to move both addReservedSymbols and
createSyntheticSections earlier. The disadvantage is that some
sections created by createSyntheticSections replace other input
sections. For example, gdb index replaces .debug_gnu_pubnames, so it
wants to run after gc sections so that it can set S->Live to false.
What this patch does instead is to move just the ElfHeader creation
early.
llvm-svn: 320390
Summary:
I also changed the message to print both the ISA and the the architecture
name for incompatible files. Previously it would be quite hard to find the
actual path of the incompatible object files in projects that have many
object files with the same name in different directories.
Reviewers: atanasyan, ruiu
Reviewed By: atanasyan
Subscribers: emaste, sdardis, llvm-commits
Differential Revision: https://reviews.llvm.org/D40958
llvm-svn: 320056
This reduces total allocations when linking clang fsds from 263.21MB
to 174.62MB.
This also has some very nice speed improvements on some
benchmarks. Chromium and clang fsds link 6% faster.
llvm-svn: 319976
This patch is to rename check CHECK and make it a C macro, so that
we can evaluate the second argument lazily.
Differential Revision: https://reviews.llvm.org/D40915
llvm-svn: 319974
This avoids allocating the error message when there is no error that
check requires.
It avoids the code duplication of inlining check.
llvm-svn: 319922
As mentioned in PR35471, shared functions for which
.plt entry address is used shows up in bfd's map files.
Patch teaches LLD to do the same.
Differential revision: https://reviews.llvm.org/D40839
llvm-svn: 319879
We fill executable sections with trap instructions (0xcc or equivalent).
If a .gnu.hash section was put into an executable segment, we created
corrupted .gnu.hash section. This patch fixes the issue.
llvm-svn: 319863
Add a new file AArch64ErrataFix.cpp that implements the logic to scan for
the Cortex-A53 Erratum 843419. This involves finding all the executable
code, disassembling the instructions that might trigger the erratum and
reporting a message if the sequence is detected.
At this stage we do not attempt to fix the erratum, this functionality
will be added in a later patch. See D36749 for proposal.
Differential Revision: https://reviews.llvm.org/D36742
llvm-svn: 319780
With fix:
Specify -soname for input dso to fix up the .dynstr section
size in different environments.
Original commit message:
As mentioned in PR35471, copied symbols did not show
in --Map output. Patch fixes that.
Differential revision: https://reviews.llvm.org/D40785
llvm-svn: 319769
When a linker script is used with a pattern like { *(.bss .bss.*) } the
InX::BssRelRo section will match against .bss.*. By matching on the name
only, in the same way that .data.rel.ro works we prevent this
from happening, but permit scripts that want to explicitly provide
a .bss.rel.ro OutputSection.
Differential Revision: https://reviews.llvm.org/D40735
llvm-svn: 319755
As mentioned in PR35471, copied symbols did not show
in --Map output. Patch fixes that.
Differential revision: https://reviews.llvm.org/D40785
llvm-svn: 319747
Previously, lld exited with an error status if the only option given to
the command was -v. GNU linkers gracefully exit in that case. This patch
makes lld behave like GNU.
Note that even with this patch, lld's -v and --version options behave
slightly differently than GNU linkers' counterparts. For example,
if you run `ld.bfd -v -v`, the version string is printed out twice.
But that is an edge case that I don't think we need to take care of.
Fixes https://bugs.llvm.org/show_bug.cgi?id=31582
Differential Revision: https://reviews.llvm.org/D40810
llvm-svn: 319717
This change actually makes the linker slightly faster. My observation
is that, with this patch, link time of clang without debug is about 1%
faster.
Differential Revision: https://reviews.llvm.org/D40697
llvm-svn: 319600
Rafael Espindola