Summary: Creates bitcode files suitable for use with ThinLTO, then checks that the linker can build an executable from them.
Reviewers: ruiu, pcc
Reviewed By: pcc
Subscribers: mehdi_amini, Prazek, llvm-commits
Differential Revision: https://reviews.llvm.org/D30277
llvm-svn: 296042
With this we complete the transition out of special output sections,
and with the previous patches it should be possible to merge
OutputSectionBase and OuputSection.
llvm-svn: 296023
With the current design an InputSection is basically anything that
goes directly in a OutputSection. That includes plain input section
but also synthetic sections, so this should probably not be a
template.
llvm-svn: 295993
For functions the linker uses a related hack: creating a plt in the
main executable that preempts the function.
Like bfd and gold, we don't disable it with nocopyreloc.
llvm-svn: 295976
We have InputSection, MergeInputSection and EhInputSection, so
isa<MergeInputSection> is equivalent to !isa<InputSection> && !isa<
EhInputSection>.
llvm-svn: 295937
We shouldn't report an error for R_*_NONE relocs since we're emitting
them when writing relocations to discarded sections.
Differential Revision: https://reviews.llvm.org/D30279
llvm-svn: 295936
I really do not understand what is going on on some Windows buildbots,
but FileCheck command on some buildbot behaves like long lines were
truncated. I'll try to find a cause of the issue, but let me relax the
test so that they'll succeed on all buildbots.
llvm-svn: 295798
I added this log message to test the /msvclto option, but
this output might confuse FileCheck. This patch attempts to fix
it by removing it.
llvm-svn: 295793
LLD is a multi-threaded program. errs() or outs() are not guaranteed
to be thread-safe (they are actually not).
LLD's message(), log() or error() are thread-safe. We should use them.
llvm-svn: 295787
This change exposes the symbol table insert method and uses it to
insert the linkerscript defined symbols directly into the symbol
table to avoid unnecessarily pulling the object out of an archive.
Differential Revision: https://reviews.llvm.org/D30224
llvm-svn: 295780
Patch fixes PR32024.
Sections that were not marked as Live has null output section.
Previously we tried to access that field and segfaulted.
Differential revision: https://reviews.llvm.org/D30188
llvm-svn: 295727
r295240 tweaked LLD to generate a symbol table when passing in
--export-dynamic, even when creating static executables. Add a test to
make sure this never regresses.
Reviewed by: ruiu, rafael
Differential Revision: https://reviews.llvm.org/D30175
llvm-svn: 295725
Previously we evaluated the values of LMA incorrectly for next cases:
.text : AT(ADDR(.text) - 0xffffffff80000000) { ... }
.data : AT(ADDR(.data) - 0xffffffff80000000) { ... }
.init.begin : AT(ADDR(.init.begin) - 0xffffffff80000000) { ... }
Reason was that we evaluated offset when VA was not assigned. For case above
we ended up with 3 loads that has similar LMA and it was incorrect.
That is critical for linux kernel.
Patch updates the offset after VA calculation. That fixes the issue.
Differential revision: https://reviews.llvm.org/D30163
llvm-svn: 295722
Previously LLD would error out just "ld.lld: error: unable to move location counter backward"
What does not really reveal the place of issue,
Patch adds location to the output.
Differential revision: https://reviews.llvm.org/D30187
llvm-svn: 295720
Previously ASSERT we implemented returned expression value.
Ex:
. = ASSERT(0x100);
would set Dot value to 0x100
Form of assert when it is assigned to Dot was implemented for
compatibility with very old GNU ld which required it.
Some scripts in the wild, including linux kernel scripts
use such ASSERTs at the end for doing different checks.
Currently we fail with "unable to move location counter backward"
for such scripts. Patch changes ASSERT to return location counter
value to fix that.
Differential revision: https://reviews.llvm.org/D30171
llvm-svn: 295703
This change moves the SymbolBodies with isLocal() == true before the global
symbols then calculating NumLocals rather than assuming all locals are
added before globals and the first NumLocals have isLocal() == true. This
permits Thunks to be moved after the pass that adds global symbols from
synthetics to the symbol table.
Differential revision: https://reviews.llvm.org/D30085
llvm-svn: 295650
Behavior races on ErrorCount. If the enqueued paths are evaluated
eagerly (in enqueuePath) then the behavior is as the test expects. But
they may not be evaluated until the future is waited on, in run() -
which is after the early return/exit on ErrorCount. (this causes the
test to fail (because in the "/ERRORCOUNT:XYZ" test, no other errors
are printed), at least for me, on linux)
This reverts commit r295507.
llvm-svn: 295590
Summary: This adds support for reporting multiple errors in a single invocation of lld-link. The limit defaults to 20 and can be changed with the /ERRORLIMIT command line parameter, or set to unlimited by passing a value of 0.
Reviewers: pcc, ruiu
Reviewed By: ruiu
Differential Revision: https://reviews.llvm.org/D29691
llvm-svn: 295507
Previously LLD crashed on on provided testcases because "/DISCARD/" was
not supported. Patch implements that.
After this I think there is no known issues with --emit-relocs implementation
required for linux kernel linking.
Differential revision: https://reviews.llvm.org/D29273
llvm-svn: 295488
I splitted it from D29273.
Since we plan to make relocatable sections as dependent for target ones for
--emit-relocs implementation, this change is required to support .eh_frame case.
EhInputSection inherets from InputSectionBase and not from InputSection.
So for case when it has relocation section, it should be able to access DependentSections
vector.
This case is real for Linux kernel.
Differential revision: https://reviews.llvm.org/D30084
llvm-svn: 295483
This is a small difference I noticed to gold and bfd. When given
--print-gc-sections, we print sections a linkerscript marks
DISCARD. The other linkers don't.
llvm-svn: 295467
This case should be possible to handle, but it is hard:
* In order to create program headers correctly, we have to scan the
sections in the order they are in the file.
* To find that order, we have to "execute" the linker script.
* The linker script can contain SIZEOF_HEADERS.
So to support this we have to start with a guess of how many headers
we need (3), run the linker script and try to create the program
headers. If it turns out we need more headers, we run the script again
with a larger SIZEOF_HEADERS.
Also, running the linker script depends on knowing the size of the
sections, so we have to finalize them. But creating the program
headers can change the value stored in some sections, so we have to
split size finalization and content finalization.
Looks like the last part is also needed for range extension thunks, so
we might support this at some point. For now just report an error
instead of producing broken files.
llvm-svn: 295458
Without this we would produce two relocation sections pointing to the
same section, which gnu tools reject.
This fixes pr31986.
The implementation of -r/--emit-reloc is getting fairly
complicated. But lets get the test passing before trying to refactor
it.
llvm-svn: 295385
Some PDBs or object files can contain references to other PDBs
where the real type information lives. When this happens,
all type indices in the original PDB are meaningless because
their records are not there.
With this patch we add the ability to pull type info from those
secondary PDBs.
Differential Revision: https://reviews.llvm.org/D29973
llvm-svn: 295382
SHF_LINK_ORDER sections adds special ordering requirements.
Such sections references other sections. Previously we would crash
if section that other were referenced to was discarded by script.
Patch fixes that by discarding all dependent sections in that case.
It supports chained dependencies, testcase is provided.
Differential revision: https://reviews.llvm.org/D30033
llvm-svn: 295332
Unfortunately, the common way of writing linker scripts seems to be
to get the output of ld.bfd --verbose and edit it a bit.
Also unfortunately, the bfd default script contains things like
.rela.dyn : { *(... .rela.data ...) }
but bfd actually ignores that for -emit-relocs, so we have to do the
same.
llvm-svn: 295324
That fixes a case when section has more than one metadata
section. Previously GC would collect one of such sections
because we had implementation that stored only last one as
dependent.
Differential revision: https://reviews.llvm.org/D29981
llvm-svn: 295298
This patch removes NeedsCopyOrPltAddr and instead add two variables,
NeedsCopy and NeedsPltAddr. This uses one more bit in Symbol class,
but the actual size doesn't increase because we had unused bits.
This should improve code readability.
llvm-svn: 295287
This is slightly inefficient than the previous code, but that is really
negligible as this function is usually called at most only a few times.
llvm-svn: 295282
Previously, space in a BSS section for copy relocations are reserved
in a special way. We directly manipulated size of the BSS section.
r294577 changed the way of doing it. Now, we create an instance of
CopyRelSection (which is a synthetic input section) for each copy
relocation.
This patch removes the remains of the old way and add CopyRelSections
to BSS sections using `addSections` function, which is the usual
way to add an input section to an output section.
llvm-svn: 295278
In the target dependent code we already always return a int64_t. In
the target independent code we carefully use uintX_t, which has the
same result given 2 complement rules.
This just simplifies the code to use int64_t everywhere.
llvm-svn: 295263
For CloudABI I'm only interested in generating non-PIC/PIE executables
on armv6 and i686, as PIE introduces larger overhead than on aarch64 and
x86_64. Still, I want to be able to instruct the linker to generate a
dynamic symbol table if requested. One example use for this is that
dynamic symbol tables can be used by programs to print nicely formatted
stacktraces, including symbol names.
Right now there seems to be some logic in LLD that it only wants to emit
dynamic symbol tables when either linking against libraries or when
building PIC. Let's extend this to also take --export-dynamic into
account.
Reviewed by: ruiu
Differential Revision: https://reviews.llvm.org/D29982
llvm-svn: 295240
The linker script lexer is context-sensitive. In the regular context,
arithmetic operator characters are regular characters, but in the
expression context, they are independent tokens. This afects how the
lexer tokenizes "3*4", for example. (This kind of expression is real;
the Linux kernel uses it.)
This patch defines function `maybeSplitExpr`. This function splits the
current token into multiple expression tokens if the lexer is in the
expression context.
Differential Revision: https://reviews.llvm.org/D29963
llvm-svn: 295225
Main intention of test was to check that
we do not crash, but for additional check
it previously run readobj for input object
instead of output.
llvm-svn: 295161
If target of R_MIPS_GOT16 relocation is a local symbol its addend
is high 16 bits of complete addend. To calculate a final value, the addend
of this relocation is read, shifted to the left and combined with addend
of paired R_MIPS_LO16 relocation. To save updated addend when the linker
produces a relocatable output, we need to store high 16 bits of the
addend's value. It is different from the case of writing the relocation
result when the linker saves a 16-bit GOT index as-is.
llvm-svn: 295159
This is still not sufficient for lld to handle its own output when a
fde points to a discarded section. I am investigating if it is better
to change the -r output or make lld able to read the current version.
llvm-svn: 295141
This is a really horrible case. If a .eh_frame points to a discarded
section, it is not clear what is the correct thing to do.
It looks like ld.bfd discards the entire .eh_frame content and gold
discards the second relocation, leaving one frame with an fde that
refers to a bogus location. This is similar to what gold does.
llvm-svn: 295133
This reverts commit r295102.
In the link of seabios the assumption seems to be that the section has
an actual address, so this is not sufficient. Changing the assembly
code to add a "a" flag seems like the correct thing to do instead of
extending this hack.
Sorry about the noise.
Original message:
Relax the restriction on what relocations can be in a non-alloc section.
The main thing that they can't have is relocations that require the
creation of gots or plt. For now also accept R_PC.
Found while linking seabios.
llvm-svn: 295130
The main thing that they can't have is relocations that require the
creation of gots or plt. For now also accept R_PC.
Found while linking seabios.
llvm-svn: 295102
If we had SHT_GROUP sections, then when -r was used we might crash.
This is PR31952.
Issue happened because we emited relocation section though its target was discared
because was a member of duplicated group. When we tried to get VA of target,
segfault happened.
Core cause is the bug that GNU as 2.27 (and probably later versions) has.
In compare with llvm-mc, it does not include relocation sections into the group,
like shown in testcase. This patch covers that case.
Differential revision: https://reviews.llvm.org/D29929
llvm-svn: 295067
Patch makes addends for addends of R_386_8, R_386_16 relocations
be sign extended.
The same we did earlier for PC ones,
currenly LLD fails to link linux kernel,
reporting relocation out of range because of this.
Differential revision: https://reviews.llvm.org/D29714
llvm-svn: 295052
Unfortunately some consumers of our .o files produced with -r expect
only one section symbol per section. That is true of at least of go's
own linker.
Combining them is a somewhat convoluted process. We have to create a
symbol for every section since we don't know which ones will be
needed. The relocation sections also have to be written first to
handle the Elf_Rel addend.
I did consider a completely different approach:
We could remove the -r special case of relocation sections when
reading. We would instead have a copyRelocs function that is used
instead of scanRelocs. It would create a DynamicReloc for each
relocation and a RelocationSection for each input relocation section.
A complication of such change is that DynamicReloc would have to take
a section index and a input section instead of a symbol since with
-emit-relocs some DynamicReloc would hold relocations referring to the
dynamic symbol table and other to the static symbol table.
That would be a pretty big change, and if we do it it is probably
better to do it as a refactoring.
llvm-svn: 294816
LLVM defines `PTHREAD_LIB` which is used by AddLLVM.cmake and various projects
to correctly link the threading library when needed. Unfortunately
`PTHREAD_LIB` is defined by LLVM's `config-ix.cmake` file which isn't installed
and therefore can't be used when configuring out-of-tree builds. This causes
such builds to fail since `pthread` isn't being correctly linked.
This patch attempts to fix that problem by renaming and exporting
`LLVM_PTHREAD_LIB` as part of`LLVMConfig.cmake`. I renamed `PTHREAD_LIB`
because It seemed likely to cause collisions with downstream users of
`LLVMConfig.cmake`.
llvm-svn: 294690
Rui Ueyama