While building a Global Offset Table try to fill the primary GOT as much
as possible because the primary GOT can be accessed in the most
effective way. If it is not possible, try to fill the last GOT in the
multi-GOT list, and finally create a new GOT if both attempts failed.
llvm-svn: 335140
microMIPS 64-bit is unsupported by LLVM starting from r335057. But such
code can be generated by GCC. Mark failed test cases as XFAIL while
decide to drop microMIPS 64-bit support from LLD too or use binary
inputs for the test.
llvm-svn: 335059
Summary: For --wrap foo --wrap foo, bfd/gold wrap the symbol only once but LLD would rotate it twice.
Reviewers: ruiu, espindola
Subscribers: emaste, arichardson, mgrang, llvm-commits
Differential Revision: https://reviews.llvm.org/D48298
llvm-svn: 334991
This is a follow up requested during post commit review for
"[lld] r333880 - [ELF] - Also use DW_AT_linkage_name when gathering information about variables for error messages."
It removes checking of the input objects since it is really excessive.
llvm-svn: 334946
Summary:
R_X86_64_GOTOFF64: S + A - GOT
R_X86_64_GOTPC{32,64}: GOT + A - P (R_GOTONLY_PC_FROM_END)
R_X86_64_GOTOFF64 should use R_GOTREL_FROM_END so that in conjunction with
R_X86_64_GOTPC{32,64}, the `GOT` term is neutralized. This also matches
the handling of R_386_GOTOFF (S + A - GOT).
Reviewers: ruiu, espindola
Subscribers: emaste, arichardson, llvm-commits
Differential Revision: https://reviews.llvm.org/D48095
llvm-svn: 334672
Summary:
Any invocation of `clang -fuse-ld=lld` that results in a link command
on a macOS host currently fails, because the Darwin lld driver does not
recognize the `-lto_library` option that Clang passes it. Fix the error
by having the Darwin driver ignore the option.
The Clang driver's macOS toolchain is written such that it will always
pass the `-lto_library` option to the linker invocation on a macOS host.
And although the DarwinLdDriver is written to ignore any unknown arguments,
because `-lto_library` begins with `-l`, the DarwinLdDriver interprets it
as a library search command, for a library named "to_library". When the
DarwinLdDriver is unable to find a library specified via `-l`, it exits
with a hard error. This causes any invocation of `clang -fuse-ld=lld`
that results in a link command on a macOS host to fail with an error.
To fix the issue, I considered two alternatives:
1. Modify the Clang Darwin toolchain to only pass `-lto_library` if lld
is *not* being used. lld doesn't support LTO on Darwin anyway, so it
can't use the option. However, I opted against this because, if and
when lld *does* support LTO on Darwin, I'll have to make another
commit to Clang in order to get it to pass the option to lld again.
2. Modify the Darwin lld driver to ignore the `-lto_library` option.
Just in case users may take this to mean LTO is supported, I also
added a warning. If and when lld supports LTO on Darwin, the same
commit that adds support for this option can remove the warning.
Option (2) seemed better to me, and is the rationale behind this commit.
Test Plan: check-lld
Reviewers: ruiu, smeenai, pcc
Reviewed By: smeenai
Subscribers: JDevlieghere, pcc, mehdi_amini, inglorion, steven_wu, llvm-commits
Differential Revision: https://reviews.llvm.org/D47994
llvm-svn: 334641
`lld-link foo.lib /wholearchive:foo.lib` should work the same way as
`lld-link /wholearchive:foo.lib foo.lib`. Previously, /wholearchive in
the former case was ignored.
Differential Revision: https://reviews.llvm.org/D47565
llvm-svn: 334552
When running with linker GC (`-opt:ref`), defined imported symbols that
are referenced but then dropped by GC end up with their `Location`
member being nullptr, which means `getChunk()` returns nullptr for them
and attempting to call `getChunk()->getOutputSection()` causes a crash
from the nullptr dereference. Check for `getChunk()` being nullptr and
bail out early to avoid the crash.
Differential Revision: https://reviews.llvm.org/D48092
llvm-svn: 334548
R_X86_64_GOTOFF64 is a relocation type to set to a distance betwween
a symbol and the beginning of the .got section. Previously, we always
created a dynamic relocation for the relocation type even though it
can be resolved at link-time.
Creating a dynamic relocation for R_X86_64_GOTOFF64 caused link failure
for some programs that do have a relocation of the type in a .text
section, as text relocations are prohibited in most configurations.
Differential Revision: https://reviews.llvm.org/D48058
llvm-svn: 334534
Summary:
Previously LLD would not add any dynamic relocations and write a module
index of 1 which is not correct for the shared library case.
This can happen when a thread-local global variable is marked as local with
a version script. With this change I am now able to link all of the FreeBSD
base system for MIPS64 with LLD.
Differential Revision: https://reviews.llvm.org/D48002
llvm-svn: 334483
Patch adds support for most of the dynamic thread pointer based relocations
for local-dynamic tls. The HIGH and HIGHA versions are missing becuase they
are not supported by the llvm integrated assembler yet.
llvm-svn: 334465
In glibc libc.so.6, the multiple versions of sys_errlist share the same Symbol instance. When sys_errlist is copy relocated, we would replace SharedSymbol with Defined in the first iteration of the following loop:
for (SharedSymbol *Sym : getSymbolsAt<ELFT>(SS))
Then in the second iteration, we think the symbol (which has been changed to Defined) is still SharedSymbol and screw up (the address ends up in the `Size` field).
llvm-svn: 334432
Almost all entries inside MIPS GOT are referenced by signed 16-bit
index. Zero entry lies approximately in the middle of the GOT. So the
total number of GOT entries cannot exceed ~16384 for 32-bit architecture
and ~8192 for 64-bit architecture. This limitation makes impossible to
link rather large application like for example LLVM+Clang. There are two
workaround for this problem. The first one is using the -mxgot
compiler's flag. It enables using a 32-bit index to access GOT entries.
But each access requires two assembly instructions two load GOT entry
index to a register. Another workaround is multi-GOT. This patch
implements it.
Here is a brief description of multi-GOT for detailed one see the
following link https://dmz-portal.mips.com/wiki/MIPS_Multi_GOT.
If the sum of local, global and tls entries is less than 64K only single
got is enough. Otherwise, multi-got is created. Series of primary and
multiple secondary GOTs have the following layout:
```
- Primary GOT
Header
Local entries
Global entries
Relocation only entries
TLS entries
- Secondary GOT
Local entries
Global entries
TLS entries
...
```
All GOT entries required by relocations from a single input file
entirely belong to either primary or one of secondary GOTs. To reference
GOT entries each GOT has its own _gp value points to the "middle" of the
GOT. In the code this value loaded to the register which is used for GOT
access.
MIPS 32 function's prologue:
```
lui v0,0x0
0: R_MIPS_HI16 _gp_disp
addiu v0,v0,0
4: R_MIPS_LO16 _gp_disp
```
MIPS 64 function's prologue:
```
lui at,0x0
14: R_MIPS_GPREL16 main
```
Dynamic linker does not know anything about secondary GOTs and cannot
use a regular MIPS mechanism for GOT entries initialization. So we have
to use an approach accepted by other architectures and create dynamic
relocations R_MIPS_REL32 to initialize global entries (and local in case
of PIC code) in secondary GOTs. But ironically MIPS dynamic linker
requires GOT entries and correspondingly ordered dynamic symbol table
entries to deal with dynamic relocations. To handle this problem
relocation-only section in the primary GOT contains entries for all
symbols referenced in global parts of secondary GOTs. Although the sum
of local and normal global entries of the primary got should be less
than 64K, the size of the primary got (including relocation-only entries
can be greater than 64K, because parts of the primary got that overflow
the 64K limit are used only by the dynamic linker at dynamic link-time
and not by 16-bit gp-relative addressing at run-time.
The patch affects common LLD code in the following places:
- Added new hidden -mips-got-size flag. This flag required to set low
maximum size of a single GOT to be able to test the implementation using
small test cases.
- Added InputFile argument to the getRelocTargetVA function. The same
symbol referenced by GOT relocation from different input file might be
allocated in different GOT. So result of relocation depends on the file.
- Added new ctor to the DynamicReloc class. This constructor records
settings of dynamic relocation which used to adjust address of 64kb page
lies inside a specific output section.
With the patch LLD is able to link all LLVM+Clang+LLD applications and
libraries for MIPS 32/64 targets.
Differential revision: https://reviews.llvm.org/D31528
llvm-svn: 334390
This causes all symbols to be exported in the final wasm binary
even if they were not compiled with default visibility.
This feature is useful for the emscripten toolchain that has a
corresponding EXPORT_ALL feature which allows the JS code to
interact with all C function.
Differential Revision: https://reviews.llvm.org/D47806
llvm-svn: 334157
The original computation for shared object symbol alignment is wrong when
st_value equals 0. It is very unusual for dso symbols to have st_value equal 0.
But when it happens, it causes obscure run time bugs.
Differential Revision: https://reviews.llvm.org/D47602
llvm-svn: 334135
If building lld without x86 support, tests that require that support should
be treated as unsupported, not errors.
Tested using:
1. cmake '-DLLVM_TARGETS_TO_BUILD=AArch64;X86'
make check-lld
=>
Expected Passes : 1406
Unsupported Tests : 287
2. cmake '-DLLVM_TARGETS_TO_BUILD=AArch64'
make check-lld
=>
Expected Passes : 410
Unsupported Tests : 1283
Patch by Joel Jones
Differential Revision: https://reviews.llvm.org/D47748
llvm-svn: 334095
Currently, when LLD do a lookup for variables location, it uses DW_AT_name attribute.
That is not always enough.
Imagine code:
namespace A {
int bar = 0;
}
namespace Z {
int bar = 1;
}
int hoho;
In this case there are 3 variables and their debug attributes are following:
A::bar has: DW_AT_name [DW_FORM_string] ("bar") DW_AT_linkage_name [DW_FORM_strp] ( .debug_str[0x00000006] = "_ZN1A3barE")
Z::bar has: DW_AT_name [DW_FORM_string] ("bar") DW_AT_linkage_name [DW_FORM_strp] ( .debug_str[0x0000003f] = "_ZN1Z3barE")
hoho has: DW_AT_name [DW_FORM_strp] ( .debug_str[0x0000004a] = "hoho") and has NO DW_AT_linkage_name attribute. Because it would be
the same as DW_AT_name and DWARF producers avoids emiting excessive data.
Hence LLD should also use DW_AT_linkage_name when it is available.
(currently, LLD fails to report location correctly because thinks that A::bar and Z::bar are the same things)
Differential revision: https://reviews.llvm.org/D47373
llvm-svn: 333880
Clang passes --plugin /path/to/LLVMgold.so to the linker when -flto is
passed. After r333607 we only ignore --plugin as a joined argument,
which means that the following argument (/path/to/LLVMgold.so) is
interpreted as an input file. This means that either every LTO'd
program ends up being linked with the gold plugin or we error out
if the plugin does not exist. The fix is to use Eq to ignore both
--plugin=foo and --plugin foo as before.
Differential Revision: https://reviews.llvm.org/D47657
llvm-svn: 333793
Since aliases don't actually need name, I removed it from Options.td
to keep the definitions concise.
Before:
-( Ignored for compatibility with GNU unless you pass --warn-backrefs
-) Ignored for compatibility with GNU unless you pass --warn-backrefs
--allow-multiple-definition Allow multiple definitions
--apply-dynamic-relocs Apply dynamic relocations to place
--as-needed Only set DT_NEEDED for shared libraries if used
--auxiliary=<value> Set DT_AUXILIARY field to the specified name
--Bdynamic Link against shared libraries
--Bshareable Build a shared object
...
After:
-( Alias for --start-group
-) Alias for --end-group
--allow-multiple-definition Allow multiple definitions
--apply-dynamic-relocs Apply dynamic relocations to place
--as-needed Only set DT_NEEDED for shared libraries if used
--auxiliary=<value> Set DT_AUXILIARY field to the specified name
--Bdynamic Link against shared libraries (default)
--Bshareable Alias for --shared
...
Differential Revision: https://reviews.llvm.org/D47588
llvm-svn: 333694
Add support for the R_PPC64_GOT_TLSLD16 relocations used to build the address of
the tls_index struct used in local-dynamic tls.
Differential Revision: https://reviews.llvm.org/D47538
llvm-svn: 333681
--push-state implemented in this patch saves the states of --as-needed,
--whole-archive and --static. It saves less number of flags than GNU linkers.
Since even GNU linkers save different flags, no one seems to care about the
details. In this patch, I tried to save the minimal number of flags to not
complicate the implementation and the siutation.
I'm not personally happy about adding the --{push,pop}-state flags though.
That options seem too hacky to me. However, gcc started using the options
since GCC 8 when GNU ld is available at the build time. Therefore, lld
is no longer a drop-in replacmenet for GNU linker for that machine
without supporting the flags.
Fixes https://bugs.llvm.org/show_bug.cgi?id=34567
Differential Revision: https://reviews.llvm.org/D47542
llvm-svn: 333646
This should be correctly implied by the linker.
This also makes the tests slightly easier to maintain and compare
with the equivalent tests under for other platforms.
Differential Revision: https://reviews.llvm.org/D47513
llvm-svn: 333567
The comment only made sense a long time ago, when --thinlto-jobs was
tied with --lto-partitions. That was changed in r283817, but the test
wasn't updated at the same time. This patch does so.
llvm-svn: 333480
Rather than using a loop to compare symbol RVAs to the starting RVAs of
sections to determine which section a symbol belongs to, just get the
output section of a symbol directly via its chunk, and bail if the
symbol doesn't have an output section, which avoids having to hardcode
logic for handling dead symbols, CodeView symbols, etc. This was
suggested by Reid Kleckner; thank you.
This also fixes writing out symbol tables in the presence of RVA table
input sections (e.g. .sxdata and .gfids). Such sections aren't written
to the output file directly, so their RVA is 0, and the loop would thus
fail to find an output section for them, resulting in a segfault. Extend
some existing tests to cover this case.
Fixes PR37584.
Differential Revision: https://reviews.llvm.org/D47391
llvm-svn: 333450
Adds handling of all the relocation types for general-dynamic thread local
storage.
Differential Revision: https://reviews.llvm.org/D47325
llvm-svn: 333420
Recently an LLD test change was made that introduced the use of
llvm-bcanalyzer. This change adds the tool to the list of LLD test
dependencies.
Reviewed by: rdhindsa, ruiu
Patch by Owen Reynolds.
llvm-svn: 333277
PPC64 maintains a compiler managed got in the .toc section. When accessing a
global variable through got-indirect access, a .toc entry is created for the
variable. The relocation for the got-indirect access will refer to the .toc
section rather than the symbol that is actually accessed. The .toc entry
contains the address of the global variable. We evaluate the offset from
r2 (which is the TOC base) to the address of the toc entry for the global
variable. Currently, the .toc is not near the .got. This causes errors because
the offset from r2 to the toc section is too large. The linker needs to add
all the .toc input sections to the .got output section, merging the compiler
managed got with the linker got. This ensures that the offsets from the TOC
base to the toc entries are not too large.
This patch puts the .toc section right after the .got section.
Differential Revision: https://reviews.llvm.org/D45833
llvm-svn: 333199
A user program may enumerate sections named with a C identifier using
__start_* and __stop_* symbols. We cannot ICF any such sections because
that could change program semantics.
Differential Revision: https://reviews.llvm.org/D47242
llvm-svn: 333054
Note that this doesn't do the right thing in the case where there is
a linker script. We probably need to move output section assignment
before ICF to get the correct behaviour here.
Differential Revision: https://reviews.llvm.org/D47241
llvm-svn: 333052
When a symbol is GC'd it can still be references by relocations
in the debug sections, but such symbols are not assigned virtual
addresses.
This change adds a new global data symbol which gets GC'd but
should still appears in the output debug info, albeit with a 0
address.
Fixes 37555
Differential Revision: https://reviews.llvm.org/D47238
llvm-svn: 333047
Previously, we had a loop to iterate over options starting with
`--plugin-opt=` and parse them by hand. But we can make OptTable
do that job for us.
Differential Revision: https://reviews.llvm.org/D47167
llvm-svn: 332935
This change adds the ability for lld to remove LEB padding from
code section. This effectively shrinks the size of the resulting
binary in proportion to the number of code relocations.
Since there will be a performance cost this is currently only active for
-O1 and above. Some toolchains may instead want to perform this
compression as a post linker step (for example running a binary through
binaryen will automatically compress these values).
I imagine we might want to make this the default in the future.
Differential Revision: https://reviews.llvm.org/D46416
llvm-svn: 332783
_init_array_start/end are placed at 0 if no ".init_array" presents,
this causes .text relocation against them become more prone to overflow.
This CL sets ".init_array" address to that of ".text" to mitigate the situation.
Review: https://reviews.llvm.org/D46200
llvm-svn: 332688
Previously we emitted 20-byte SHA1 hashes. This is overkill
for identifying debug info records, and has the negative side
effect of making object files bigger and links slower. By
using only the last 8 bytes of a SHA1, we get smaller object
files and ~10% faster links.
This modifies the format of the .debug$H section by adding a new
value for the hash algorithm field, so that the linker will still
work when its object files have an old format.
Differential Revision: https://reviews.llvm.org/D46855
llvm-svn: 332669
The prefix includes type kind, which is important to preserve. Two
different type leafs can easily have the same interior record contents
as another type.
We ran into this issue in PR37492 where a bitfield type record collided
with a const modifier record. Their contents were bitwise identical, but
their kinds were different.
llvm-svn: 332664
Patch by Mark Kettenis.
Make ALIGN work in linker scripts used with the -r option. This works in
GNU ld (ld.bfd) and is used to generate the "random gap" object for
linking the OpenBSD kernel.
Differential Revision: https://reviews.llvm.org/D46839
llvm-svn: 332656
Previously we would always write a hash of the binary into the
PE file, for reproducible builds. This breaks AppCompat, which
is a feature of Windows that relies on the timestamp in the PE
header being set to a real value (or at the very least, a value
that satisfies certain properties).
To address this, we put the old behavior of writing the hash
behind the /Brepro flag, which mimics MSVC linker behavior. We
also match MSVC default behavior, which is to write an actual
timestamp to the PE header. Finally, we add the /TIMESTAMP
option (an lld extension) so that the user can specify the exact
value to be used in case he/she manually constructs a value which
is both reproducible and satisfies AppCompat.
Differential Revision: https://reviews.llvm.org/D46966
llvm-svn: 332613
Currently, LLD marks all non-allocatable sections except SHF_REL[A] as Live
when doing GC.
This can be a reason of the crash when SHF_LINK_ORDER sections
are involved, because their parents can be dead.
We should do GC for them correctly. The patch implements it.
Differential revision: https://reviews.llvm.org/D46880
llvm-svn: 332589
This CL places .dynsym and .dynstr at the beginning of SHF_ALLOC
sections. We do this to mitigate the possibility that huge .dynsym and
.dynstr sections placed between ro-data and text sections cause
relocation overflow.
Differential Revision: https://reviews.llvm.org/D45788
llvm-svn: 332374
The --keep-unique <symbol> option is taken from gold. The intention is that
<symbol> will be prevented from being folded by ICF. Although not
specifically mentioned in the documentation <symbol> only matches
global symbols, with a warning if the symbol is not found.
The implementation finds the Section defining <symbol> and removes it from
the set of sections considered for ICF.
Differential Revision: https://reviews.llvm.org/D46755
llvm-svn: 332332
This allows producing pdb debug info. This is an LLD specific option
since GCC and GNU binutils doesn't support the PDB file format.
Differential Revision: https://reviews.llvm.org/D46796
llvm-svn: 332327
Since we a no longer using this function for the wasm start
section we don't actually care what its signature is.
Differential Revision: https://reviews.llvm.org/D46594
llvm-svn: 332308
The relocation R_PPC64_REL64 should return R_PC for getRelExpr since it
computes S + A - P.
Differential Revision: https://reviews.llvm.org/D46766
llvm-svn: 332259
The relocation R_PPC64_REL32 should return R_PC for getRelExpr since it
computes S + A - P.
Differential Revision: https://reviews.llvm.org/D46586
llvm-svn: 332252
If a symbol with an undefined version in a DSO is not going to be
exported into the dynamic symbol table then do not give an error message
for the missing version. This can happen with the --exclude-libs option
which implicitly gives all symbols in a static library the local version.
This matches the behavior of ld.gold and is exploited by the Bionic
dynamic linker on Arm.
Differential Revision: https://reviews.llvm.org/D43126
llvm-svn: 332224
This is needed to avoid merging two functions with identical
instructions but different xdata. It also reduces binary size by
deduplicating identical pdata sections.
Fixes PR35337.
Differential Revision: https://reviews.llvm.org/D46672
llvm-svn: 332169
We discovered (crbug.com/838449#c24) that string tail merging can
negatively affect compressed binary size, so provide a flag to turn
it off for users who care more about compressed size than uncompressed
size.
Differential Revision: https://reviews.llvm.org/D46780
llvm-svn: 332149
Both R_PPC_CALL and R_PPC_CALL_PLT Exprs map to the R_PPC64_REL24 relocation
which has the form Sym + addend - P.
Differential Revision: https://reviews.llvm.org/D46654
llvm-svn: 332127
Summary:
Suppose we visit symbols in this order:
1. weak definition of foo in a lazy object
2. reference of foo
3 (optional). definition of foo
bfd/gold allows 123 but not 12.
Current --warn-backrefs implementation will report both cases as a backward reference. With this change, both 123 (intended) and 12 (unintended) are allowed. The usage of weak definitions usually imply there are also global definitions, so the trade-off is justified.
Reviewers: ruiu, espindola
Subscribers: emaste, arichardson, llvm-commits
Differential Revision: https://reviews.llvm.org/D46624
llvm-svn: 332061
The previous CL changes the order of output sections, which causes address changes in test cases.
Review: https://reviews.llvm.org/D46730
llvm-svn: 332054
This CL is to mitigate R_X86_64_PC32 relocation overflow problems for huge binaries that has near 4G allocated sections.
By examining those binaries, there're 2 issues contributes to the problem:
1). huge ".dynsym" and ".dynstr" stands in the way between .rodata and .text
2). _init_array_start/end are placed at 0 if no ".init_array" presents, this causes .text relocation against them become more prone to overflow.
This CL addresses 1st problem (the 2nd will be addressed in another CL.) by assigning a smaller sortrank to .dynsym and .dynstr thus they no longer stand in between.
llvm-svn: 332038
Merging data segments produces smaller code sizes because each segment
has some boilerplate. Therefore, merging data segments is generally the
right approach, especially with wasm where binaries are typically
delivered over the network.
However, when analyzing wasm binaries, it can be helpful to get a
conservative picture of which functions are using which data
segments[0]. Perhaps there is a large data segment that you didn't
expect to be included in the wasm, introduced by some library you're
using, and you'd like to know which library it was. In this scenario,
merging data segments only makes the analysis worse.
Alternatively, perhaps you will remove some dead functions by-hand[1]
that can't be statically proven dead by the compiler or lld, and
removing these functions might make some data garbage collect-able, and
you'd like to run `--gc-sections` again so that this now-unused data can
be collected. If the segments were originally merged, then a single use
of the merged data segment will entrench all of the data.
[0] https://github.com/rustwasm/twiggy
[1] https://github.com/fitzgen/wasm-snip
Patch by Nick Fitzgerald!
Differential Revision: https://reviews.llvm.org/D46417
llvm-svn: 332013
A non-alloc note section should not have a PT_NOTE program header.
Found while linking ghc (Haskell compiler) with lld on FreeBSD.
ghc emits a .debug-ghc-link-info note section (as the name suggests, it
contains link information) as a SHT_NOTE section without SHF_ALLOC set.
For this case ld.bfd does not emit a PT_NOTE segment for the
.debug-ghc-link-info section. lld previously emitted a PT_NOTE with
p_vaddr = 0 and FreeBSD's rtld segfaulted when trying to parse a note at
address 0.
llvm.org/pr37361
Differential Revision: https://reviews.llvm.org/D46623
llvm-svn: 331973
Reviewed by: ruiu, grimar, espindola
Differential Revision: https://reviews.llvm.org/D44562
Summary:
r331971 changes the debug line parser interface to report LLVM errors in an
interface that different executables can use, rather than always being printed
directly as warnings to stderr. This change allows LLD to make use of the new
interface and call its own warning methods to report problems.
llvm-svn: 331972
Previously this was only supported when specified on the command line
or in directives.
Differential Revision: https://reviews.llvm.org/D46244
llvm-svn: 331900
Adds support for .glink resolver stubs from the example implementation in the V2
ABI (Section 4.2.5.3. Procedure Linkage Table). The stubs are written to the
PltSection, and the sections are renamed to match the PPC64 ABI:
.got.plt --> .plt Type = SHT_NOBITS
.plt --> .glink
And adds the DT_PPC64_GLINK dynamic tag to the dynamic section when the plt is
not empty.
Differential Revision: https://reviews.llvm.org/D45642
llvm-svn: 331840
Separate output sections for selected text section prefixes to enable TLB optimizations and for readablilty.
Differential Revision: https://reviews.llvm.org/D45841
llvm-svn: 331823
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
Some MIPS relocations depend on "gp" value. By default, this value has
0x7ff0 offset from a .got section. But relocatable files produced by a
compiler or a linker might redefine this default value and we have to
use it for a calculation of the relocation result. When we generate EXE
or DSO it's trivial. Generating a relocatable output is more difficult
case because the linker does calculate relocations in this case and
cannot store individual "gp" values used by each input object file.
As a workaround we add the "gp" value to the relocation addend.
This fixes https://llvm.org/pr31149
Differential revision: https://reviews.llvm.org/D45972
llvm-svn: 331772
In the recognise test convert some ST1 multiple structure to ST1 single
structure to test the isST1SingleOpcode() function.
Differential Revision: https://reviews.llvm.org/D46263
llvm-svn: 331752
Add two test cases to improve the code coverage of ThunkSection creation
when there are no existing ThunkSections in range. There are two test
cases, one where a new section can be created and another to trigger the
"InputSection too large for range extension thunk" error message. A recent
code coverage report showed that this section of code wasn't covered by a
test case.
Differential Revision: https://reviews.llvm.org/D46261
llvm-svn: 331751
Summary: This is not technically required, but glibc unwind-dw2-fde.c classify_object_over_fdes expects there is a CIE record length 0 as a terminator.
Reviewers: ruiu, espindola
Subscribers: emaste, arichardson, llvm-commits
Differential Revision: https://reviews.llvm.org/D46566
llvm-svn: 331708
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
On PowerPC calls to functions through the plt must be done through a call stub
that is responsible for:
1) Saving the toc pointer to the stack.
2) Loading the target functions address from the plt into both r12 and the
count register.
3) Indirectly branching to the target function.
Previously we have been emitting these call stubs to the .plt section, however
the .plt section should be reserved for the lazy symbol resolution stubs. This
patch moves the call stubs to the text section by moving the implementation from
writePlt to the thunk framework.
Differential Revision: https://reviews.llvm.org/D46204
llvm-svn: 331607
Specifically add support for custom sections that contain
relocations, and for the two new relocation types needed
by DWARF sections.
See: https://reviews.llvm.org/D44184
Patch by Yury Delendik!
Differential Revision: https://reviews.llvm.org/D44184
llvm-svn: 331566
The current support for V1 ABI in LLD is incomplete.
This patch removes V1 ABI support and changes the default behavior to V2 ABI,
issuing an error when using the V1 ABI. It also updates the testcases to V2
and removes any V1 specific tests.
Differential Revision: https://reviews.llvm.org/D46316
llvm-svn: 331529
Android AOSP has started specifying -m aarch64_elf64_le_vec as supported
by gold and BFD. This is a simple change to add the emulation so that LLD
doesn't immediately error when used as a linker in an AOSP build.
Differential Revision: https://reviews.llvm.org/D46429
llvm-svn: 331521
Implement the following relocations for AArch64:
R_AARCH64_TLSLE_LDST8_TPREL_LO12_NC
R_AARCH64_TLSLE_LDST16_TPREL_LO12_NC
R_AARCH64_TLSLE_LDST32_TPREL_LO12_NC
R_AARCH64_TLSLE_LDST64_TPREL_LO12_NC
R_AARCH64_TLSLE_LDST128_TPREL_LO12_NC
These are specified in ELF for the 64-bit Arm Architecture.
Fixes pr36727
Differential Revision: https://reviews.llvm.org/D46255
llvm-svn: 331511
Now only IMAGE_REL_ARM64_ABSOLUTE and IMAGE_REL_ARM64_TOKEN
are unhandled.
Also add range checks for the existing BRANCH26 relocation.
Differential Revision: https://reviews.llvm.org/D46354
llvm-svn: 331505
PPC64 V2 ABI describes two entry points to a function. The global entry point
sets up the TOC base pointer. When calling a local function, the call should
branch to the local entry point rather than the global entry point.
Section 3.4.1 describes using the 3 most significant bits of the st_other
field to find out how many instructions there are between the local and global
entry point. This patch adds the correct offset required to branch to the local
entry point of a function.
Differential Revision: https://reviews.llvm.org/D45729
llvm-svn: 331046
This is slightly simpler to read IMHO. Now if a symbol has a position
in the file, it is Defined.
The main motivation is that with this a SharedSymbol doesn't need a
section, which reduces the size of SymbolUnion.
With this the peak allocation when linking chromium goes from 568.1 to
564.2 MB.
llvm-svn: 330966
It returns a different Expr only in the case of creating a function
symbol pointing to its plt entry. We can just add a call to
addPltEntry to avoid that and return void.
With this patch further simplifications of how we handle copy
relocations are possible.
llvm-svn: 330960
Currently, LLD supports ASSERT as a separate command.
We support two forms now.
Assign expression-form: . = ASSERT(0x100)
(old GNU ld required it and some scripts in the wild are still using
something like . = ASSERT((_end - _text <= (512 * 1024 * 1024)), "kernel image bigger than KERNEL_IMAGE_SIZE");
Nowadays above is not a mandatory form and command-like form is commonly used:
ASSERT(<expr>, "text);
The return value of the ASSERT is Dot. That was implemented in D30171.
It looks like (2) is just a short version of (1) then.
GNU ld does *not* list ASSERT as a SECTIONS command:
https://sourceware.org/binutils/docs/ld/SECTIONS.html#SECTIONS
Given above we probably can change ASSERT to be an assignment to Dot.
That makes the rest of the code much simpler. Patch do that.
Differential revision: https://reviews.llvm.org/D45434
llvm-svn: 330814
The fix is to copy Used when replacing the symbol.
Original message:
Do not keep shared symbols created from garbage-collected eliminated DSOs.
If all references to a DSO happen to be weak, and if the DSO is
specified with --as-needed, the DSO is not added to DT_NEEDED.
If that happens, we also need to eliminate shared symbols created
from the DSO. Otherwise, they become dangling references that point
to non-exsitent DSO.
Fixes https://bugs.llvm.org/show_bug.cgi?id=36991
Differential Revision: https://reviews.llvm.org/D45536
llvm-svn: 330788
The PPC64 V2 ABI restores the toc base by loading from an offset of 24 from r1.
This patch fixes the offset and updates the testcases from V1 to V2. It also
issues an error when a nop is missing after a call to an external function.
Differential Revision: https://reviews.llvm.org/D45892
llvm-svn: 330600
Sam Clegg