As of rL215127, FileCheck has an -allow-empty flag,
so this could be used instead of writing a dummy line.
But it looks like the log is never empty now, so not
even that is needed.
llvm-svn: 328862
I tried a few different designs to find a way to implement it without
too much hassle and settled down with this. Unlike before, object files
given as arguments for --just-symbols are handled as object files, with
an exception that their section tables are handled as if they were all
null.
Differential Revision: https://reviews.llvm.org/D42025
llvm-svn: 328852
A short thunk uses a direct branch (b or b.w) instruction, and is used
when the target has the same thumbness as the thunk and is within
direct branch range (32MB for ARM, 16MB for Thumb-2). Reduces the
size of Chromium for Android's .text section by around 160KB.
Differential Revision: https://reviews.llvm.org/D44963
llvm-svn: 328846
There are two FPMs in an MSF file, the idea being that for
incremental updates you can write to the alternate one and then
atomically swap them on commit. LLVM defaulted to using FPM1
on the first commit, but this differs from Microsoft's behavior
which is to default to using FPM2 on the first commit. To
eliminate some byte-level file differences, this patch changes
LLVM's default to also be FPM2.
Additionally, LLVM was trying to be "smart" about marking FPM
pages allocated. In addition to marking every page belonging
to the alternate FPM as unallocated, LLVM also marked pages at
the end of the main FPM which were not needed as unallocated.
In order to match the behavior of Microsoft-generated PDBs, we
now always mark every FPM block as allocated, regardless of
whether it is in the main FPM or the alt FPM, and regardless of
whether or not it describes blocks which are actually in the file.
This has the side benefit of simplifying our code.
llvm-svn: 328812
This patch fixes an issue introduced in r328810 which made the algorithm
to always run the loop O(n^2) times, though we can break early. The
output remains the same.
llvm-svn: 328811
The PLT retpoline support for X86 and X86_64 did not include the padding
when writing the header and entries. This issue was revealed when linker
scripts were used, as this disables the built-in behaviour of filling
the last page of executable segments with trap instructions. This
particular behaviour was hiding the missing padding.
Added retpoline tests with linker scripts.
Differential Revision: https://reviews.llvm.org/D44682
llvm-svn: 328777
NonLocal is technically more accurate, but we already use the term
"Global" to specify the non-local part of the symbol table, and
Local <-> Global is easier to digest.
llvm-svn: 328740
This fixes pr36623.
The problem is that we have to parse versions out of names before LTO
so that LTO can use that information.
When we get the LTO produced .o files, we replace the previous symbols
with the LTO produced ones, but they still have @ in their names.
We could just trim the name directly, but calling parseSymbolVersion
to do it is simpler.
llvm-svn: 328738
Also make certain Thunk methods non-const as this will be required for
an upcoming change.
Differential Revision: https://reviews.llvm.org/D44961
llvm-svn: 328732
This enables callback-style programming where the JavaScript environment
can call back into the Wasm environment using a function pointer
received from the module.
Differential Revision: https://reviews.llvm.org/D44427
llvm-svn: 328643
Some tools (dwarfdump for example) get confused by the current -O0 -r
output since it has multiple copies of .debug_str.
We cannot just merge sections with the same name as they can have
different sh_entsize.
We could have duplicated logic for merging sections based on name and
sh_entsize, but it seems better to just use the existing logic by
enabling optimizations.
llvm-svn: 328640
The Data member of synthetic section's is not valid and empty. The Data
member is required to be valid by ICF as it is used by ICF to determine
the equality of section contents. Therefore, exclude synthetic sections
from ICF.
Fixes bug PR36910.
Differential Revision: https://reviews.llvm.org/D44923
llvm-svn: 328624
SharedFile::parseRest function grew organically and got a bit hard to
understand. This patch refactor it. This patch also adds comments.
Differential Revision: https://reviews.llvm.org/D44860
llvm-svn: 328579
When the target saves ElfSym::GlobalOffsetTable in the .got rather than
.got.plt, Target->GotHeaderEntriesNum states the number of extra entries
required in the .got. Rather than having to add Target->GotHeaderEntriesNum to
NumEntries in every function which refers to NumEntries, this patch changes the
initial value of NumEntries in the constructor.
Differential Revision: https://reviews.llvm.org/D44744
llvm-svn: 328559
Currently, we might have a bug with scripts like below:
.foo : ALIGN(8)
{
*(.foo)
} > ram
because do not expand the memory region when doing ALIGN.
This might result in file range overlaps. The patch fixes the issue.
Differential revision: https://reviews.llvm.org/D44730
llvm-svn: 328479
Currently when we build input sections list in linker script
we ignore all rel[a] sections. That was done to support
scripts like .rela.dyn : { *(.rela.data) } for emit relocs.
Though as a result following scripts were also silently ignored:
/DISCARD/ : { *(.rela.plt)
/DISCARD/ : { *(.rela.dyn)
and we produced output with this sections. That is not ideal.
The solution this patch suggests is simple: do not ignore synthetic
rel[a] sections. That way we can enable common discarding logic
for them and report a proper error.
Differential revision: https://reviews.llvm.org/D41640
llvm-svn: 328419
Previously, we used 0 as an alias for VER_NDX_GLOBAL and had a dummy
entry in SharedFile::Verdefs so that the access to the array is within
its boundary. But that's not straightforwad. We can just stop doing both.
llvm-svn: 328401
Since SectionBase::getOutputSection handles ICF replaces and
SectionBase::getOffset was handling it in some cases, it is more
consistent to have getOffset always handle it.
llvm-svn: 328391
This was reverted several times due to what ultimately turned out
to be incompatibilities in our serialized hash table format.
Several changes went in prior to this to fix those issues since
they were more fundamental and independent of supporting injected
sources, so now that those are fixed this change should hopefully
pass.
llvm-svn: 328363
When investigating bugs in PDB generation, the first step is
often to do the same link with link.exe and then compare PDBs.
But comparing PDBs is hard because two completely different byte
sequences can both be correct, so it hampers the investigation when
you also have to spend time figuring out not just which bytes are
different, but also if the difference is meaningful.
This patch fixes a couple of cases related to string table emission,
hash table emission, and the order in which we emit strings that
makes more of our bytes the same as the bytes generated by MS PDBs.
Differential Revision: https://reviews.llvm.org/D44810
llvm-svn: 328348
When looking for the output section and the output offset the
expectation was that the caller had looked at Repl. That works fine
for InputSections, but in the case of MergeInputSections the caller
doesn't have the section that is actually replaced.
The original testcase was failing because getOutputSection was
returning null. The slightly extended testcase also checks that
getOffset also checks Repl.
I will send a refactoring separetelly.
llvm-svn: 328332
This fixes PR36367 which is about segfault when --emit-relocs is
used together with .eh_frame sections which happens because
of reordering of regular and .rel[a] sections.
Path changes loop that iterates over input sections to create
relocation target sections first.
Differential revision: https://reviews.llvm.org/D44679
llvm-svn: 328299
Currently lld just parses the .debug_line section assuming that there
is only one compile unit. That assumption is false (PR36793).
I have a patch that changes lld to iterate over the compile units and
parse the portions of the .debug_line they point to (which fixes
PR36793).
A problem is that we will then need a compiler unit pointing to
.debug_line for lld to see it.
It seems like bfd has the same restriction.
This patch updates existing tests to add a minimal compile unit so
that they still work with PR36793 fixed.
llvm-svn: 328215
The relocations R_PPC64_REL16_LO and R_PPC64_REL16_HA should return R_PC
for getRelExpr since they compute #lo(S + A – P) and #ha(S + A – P).
Differential Revision: https://reviews.llvm.org/D44648
llvm-svn: 328103
Patch teaches LLD to hint user about -fdebug-types-section flag
if relocation overflow happens in debug section.
Differential revision: https://reviews.llvm.org/D40954
llvm-svn: 328081
This is still failing on a different bot this time due to some
issue related to hashing absolute paths. Reverting until I can
figure it out.
llvm-svn: 328014
The issue causing this to fail in certain configurations
should be fixed.
It was due to the fact that DIA apparently expects there to be
a null string at ID 1 in the string table. I'm not sure why this
is important but it seems to make a difference, so set it.
llvm-svn: 328002
There are no reasons for them to be STV_DEFAULT,
recently bfd did the same change.
Differential revision: https://reviews.llvm.org/D44566
llvm-svn: 327983
It seems @LLVM_LIBXML2_ENABLED@ doesn't always get set to 0 when not available,
but to nothing, which broke parsing of lit.site.cfg.py.
> @LLVM_LIBXML2_ENABLED@ will be replaced with 0 or 1. Putting quotes
> around that is unnecessary and just makes it harder to use the value.
> This matches what have_zlib does below.
>
> This also puts the flag together with the feature-related ones instead
> of the path-related flags.
llvm-svn: 327966
@LLVM_LIBXML2_ENABLED@ will be replaced with 0 or 1. Putting quotes
around that is unnecessary and just makes it harder to use the value.
This matches what have_zlib does below.
This also puts the flag together with the feature-related ones instead
of the path-related flags.
llvm-svn: 327964
We do not have test showing we explicitly reject objects
where relocation section goes before the target, i.e
.rel[a].text is listed before .text, for example.
The patch adds it.
llvm-svn: 327963
Choosing a Shift2 value based on wordsize is cargo-culted from gold.
Assuming that djb hash is a good hash function, choosing bits [4,9]
shouldn't be any worse or better than choosing bits [5,10]. We shouldn't
have copied that behavior that we can't justify in the first place.
Differential Revision: https://reviews.llvm.org/D44547
llvm-svn: 327921
We found that when you pass --allow-multiple-definitions or `-z muldefs`
to GNU linkers, they don't complain about duplicate symbols at all. They
don't even print out warnings on it. We emit warnings in that case.
If you pass --fatal-warnings, that difference results in a link failure.
Differential Revision: https://reviews.llvm.org/D44549
llvm-svn: 327920
Natvis is a debug language supported by Visual Studio for
specifying custom visualizers. The /NATVIS option is an
undocumented link.exe flag which will take a .natvis file
and "inject" it into the PDB. This way, you can ship the
debug visualizers for a program along with the PDB, which
is very useful for postmortem debugging.
This is implemented by adding a new "named stream" to the
PDB with a special name of /src/files/<natvis file name>
and simply copying the contents of the xml into this file.
Additionally, we need to emit a single stream named
/src/headerblock which contains a hash table of embedded
files to records describing them.
This patch adds this functionality, including the /NATVIS
option to lld-link.
Differential Revision: https://reviews.llvm.org/D44328
llvm-svn: 327895
This patch adds changes to start supporting the Power 64-Bit ELF V2 ABI.
This includes:
- Changing the ElfSym::GlobalOffsetTable to be named .TOC.
- Creating a GotHeader so the first entry in the .got is .TOC.
- Setting the e_flags to be 1 for ELF V1 and 2 for ELF V2
Differential Revision: https://reviews.llvm.org/D44483
llvm-svn: 327871
This is the same as 327248 except Arm defining _GLOBAL_OFFSET_TABLE_ to
be the base of the .got section as some existing code is relying upon it.
For most Targets the _GLOBAL_OFFSET_TABLE_ symbol is expected to be at
the start of the .got.plt section so that _GLOBAL_OFFSET_TABLE_[0] =
reserved value that is by convention the address of the dynamic section.
Previously we had defined _GLOBAL_OFFSET_TABLE_ as either the start or end
of the .got section with the intention that the .got.plt section would
follow the .got. However this does not always hold with the current
default section ordering so _GLOBAL_OFFSET_TABLE_[0] may not be consistent
with the reserved first entry of the .got.plt.
X86, X86_64 and AArch64 will use the .got.plt. Arm, Mips and Power use .got
Fixes PR36555
Differential Revision: https://reviews.llvm.org/D44259
llvm-svn: 327823
Reid pointed out the string table for supporting long section names is a
BFD extension and the comments should reflect that. Explicitly spell out
link.exe's and binutil's behavior around section names and the rationale
for LLD's behavior.
Differential Revision: https://reviews.llvm.org/D42659
llvm-svn: 327736
This change broke ARM code that expects to be able to add
_GLOBAL_OFFSET_TABLE_ to the result of an R_ARM_REL32.
I will provide a reproducer on llvm-commits.
llvm-svn: 327688
In COFF, duplicate string literals are merged by placing them in a
comdat whose leader symbol name contains a specific prefix followed
by the hash and partial contents of the string literal. This gives
us an easy way to identify sections containing string literals in
the linker: check for leader symbol names with the given prefix.
Any sections that are identified in this way as containing string
literals may be tail merged. We do so using the StringTableBuilder
class, which is also used to tail merge string literals in the ELF
linker. Tail merging is enabled only if ICF is enabled, as this
provides a signal as to whether the user cares about binary size.
Differential Revision: https://reviews.llvm.org/D44504
llvm-svn: 327668
This makes the design a little more similar to the ELF linker and
should allow for features such as ARM range extension thunks to be
implemented more easily.
Differential Revision: https://reviews.llvm.org/D44501
llvm-svn: 327667
Patch teaches LLD to print BYTE/SHORT/LONG/QUAD and
location move commands to the map file.
Differential revision: https://reviews.llvm.org/D44004
llvm-svn: 327612
I definitely didn't run the tests before committing :(
Most of these tests failed because the LLD map file output changed,
moving the functions from the main text section to a new per-function
section.
ICF also started to fire in a few cases, leading to new layouts.
llvm-svn: 327571
This is an option to print out a table of symbols and filenames.
The output format of this option is the same as GNU, so that it can be
processed by the same scripts as before after migrating from GNU to lld.
This option is mildly useful; we can live without it. But it is pretty
convenient sometimes, and it can be implemented in 50 lines of code, so
I think lld should support this option.
Differential Revision: https://reviews.llvm.org/D44336
llvm-svn: 327565
GNU ld has got a number of different flags for adjusting how to
behave around stdcall functions. The --kill-at flag strips the
trailing sdcall suffix from exported functions (which otherwise
is included by default in MinGW setups).
This also strips it from the corresponding import library though.
That makes it hard to link to such an import library from code
that calls the functions - but this matches what GNU ld does with
this flag. Therefore, this flag is probably not sensibly used
together with import libraries, but probably mostly when creating
some sort of plugin, or if creating the import library separately
with dlltool.
Differential Revision: https://reviews.llvm.org/D44292
llvm-svn: 327561
This tests that LLVM emits the relocations that /guard:cf needs to
identify address taken.
This was PR36624, which was fixed in r327557.
llvm-svn: 327559
This "fixes" PR36678 by just producing an error when we find a case
where we would produce an plt entry that used ebx but ebx would not be
set.
llvm-svn: 327542
This reduces the number of lookups to one per COMDAT group, rather than
one per symbol in a COMDAT group.
Differential Revision: https://reviews.llvm.org/D44344
llvm-svn: 327523
Previously, Config->InitialMemory/MaxMemory were hooked up to some
commandline args but had no effect at all.
Differential Revision: https://reviews.llvm.org/D44393
llvm-svn: 327508
Currently, we can end up with NBuckets==0 and android loader
does not like it (PR36537).
Seems we can go with a minimal amount of changes here for simplicity
and be consistent with gold and so just always use >= 1 value for NBuckets.
Differential revision: https://reviews.llvm.org/D44422
llvm-svn: 327481
Patch do the following changes:
* Test case was converted from MIPS to x86.
* Removed part of the test checking we are able to produce a valid output.
Since we do that already in other tests, this one's intention should be
only to check we are still able to report overlaps and/or produce
broken output with overlaps.
Differential revision: https://reviews.llvm.org/D44438
llvm-svn: 327480
This fixes issues found on the wasm waterfall related to relocations
with addends. Undefined symbols, even those with addends should
always have a provisional value of zero. At least this is what llvm
emits (and I believe this is true for ELF too).
Differential Revision: https://reviews.llvm.org/D44451
llvm-svn: 327468
This follows recently started direction and sometimes
allows to fully get rid from `echo` calls.
I'll rename changed files to *.test in a follow-up.
llvm-svn: 327410
Previously, Config->Demangle was uninitialised (not hooked up to
commandline handling)
Differential Revision: https://reviews.llvm.org/D44301
llvm-svn: 327390
This finishes PR35877.
INSERT BEFORE used similar to INSERT AFTER,
it inserts sections before the given target section.
Differential revision: https://reviews.llvm.org/D44380
llvm-svn: 327378
This is part of PR36515.
With some linkerscripts it is possible to get file offset overlaps
and overflows. Currently LLD checks overlaps in checkNoOverlappingSections().
And also we allow broken output with --no-inhibit-exec.
Problem is that sometimes final offset of sections is completely broken
and we calculate output file size wrong and might crash.
Patch implements check to verify that there is no output section
which offset exceeds file size.
Differential revision: https://reviews.llvm.org/D43819
llvm-svn: 327376
This fixes PR36598.
LLD currently crashes when we have empty output section
with SHF_LINK_ORDER flag. This might happen if we place an
empty synthetic section in the linker script, but keep output
section alive with the use of additional symbol, for example.
The patch fixes the issue by dropping all special flags
for empty sections.
Differential revision: https://reviews.llvm.org/D44376
llvm-svn: 327374
Currently lld creates plain plt entries when a R_386_PC32 resolves to
a symbol in a shared library. That is a bug (PR36678). Don't depend on
that behavior on this test.
llvm-svn: 327357
Verify that the location where a relocation is about the be
applied contains the expected existing value.
This is essentially a sanity check to catch bugs in the compiler
and the linker.
Differential Revision: https://reviews.llvm.org/D44349
llvm-svn: 327325
This bug was found by accident while trying to expand out testcases
for imported symbols, and is covered by the additional test case.
Differential Revision: https://reviews.llvm.org/D44331
llvm-svn: 327290
This matches the existing ordering that's been there for globals
for a while (__stack_pointer coming first).
Differential Revision: https://reviews.llvm.org/D44333
llvm-svn: 327286
This makes the output of some flag names in warning messages consistent with
the output of /? and the output of flags in most other diagnostics.
https://reviews.llvm.org/D44307
llvm-svn: 327261
AFTER keyword is mandatory and consume() was
used by mistake here. We accepted broken script before
this patch, testcase shows the issue.
llvm-svn: 327260
the start of the .got.plt section so that _GLOBAL_OFFSET_TABLE_[0] =
reserved value that is by convention the address of the dynamic section.
Previously we had defined _GLOBAL_OFFSET_TABLE_ as either the start or end
of the .got section with the intention that the .got.plt section would
follow the .got. However this does not always hold with the current
default section ordering so _GLOBAL_OFFSET_TABLE_[0] may not be consistent
with the reserved first entry of the .got.plt.
X86, X86_64, Arm and AArch64 will use the .got.plt. Mips and Power use .got
Fixes PR36555
Differential Revision: https://reviews.llvm.org/D44259
llvm-svn: 327248
toString(T) is a stringize function for an object of type T. Each type
that has that function defined should know how to stringize itself, and
there should be one string representation of an object. Passing a
"supplemental" argument to toString() breaks that princple. We shouldn't
add a second parameter to that function.
Differential Revision: https://reviews.llvm.org/D44323
llvm-svn: 327182
This avoids creating multiple thunks for symbols with aliases or which
belong to ICF'd sections. This patch reduces the size of Chromium for
Android by 260KB (0.8% of .text).
Differential Revision: https://reviews.llvm.org/D44284
llvm-svn: 327154
This error case is described in Linking.md. The operand for call requires
generation of a synthetic stub.
Differential Revision: https://reviews.llvm.org/D44028
llvm-svn: 327151
Previously we created __wasm_call_ctors with null InputFunction, and
added the InputFunction later. Now we create the SyntheticFunction with
null body, and set the body later.
Differential Revision: https://reviews.llvm.org/D44206
llvm-svn: 327149
In what appears to be a copy-and-paste error, lld currently only
installs libraries if the lld tools are configured to build.
Instead, lld should allow the libraries to be installed even if the lld
tools are not being built. Additionally, if users want to only install
the tools and not the libraries, the LLVM way of doing that is by
checking for LLVM_INSTALL_TOOLCHAIN_ONLY.
This fixes PR35960.
llvm-svn: 327126
This fixes the broken tests that were causing failures. The tests
before were verifying that the time stamp was 0, but now that we
are actually writing a timestamp, I just removed the match against
the timestamp value.
llvm-svn: 327049
Our code assumes all input sections in an output SHF_LINK_ORDER
section has SHF_LINK_ORDER flag. We do not check that and that can cause a crash.
That happens because we call
std::stable_sort(Sections.begin(), Sections.end(), compareByFilePosition);,
where compareByFilePosition predicate does not expect to see
null when calls getLinkOrderDep.
The same might happen when sections refer to non-regular sections.
Test cases demonstrate the issues, patch fixes them.
Differential revision: https://reviews.llvm.org/D44193
llvm-svn: 327006
This implements INSERT AFTER in a following way:
During reading scripts it collects all insert statements.
After we done and read all files it inserts statements into script commands list.
With that:
* Rest of code does know nothing about INSERT.
* Approach is straightforward and have no visible limitations.
* It is also easy to support INSERT BEFORE (was seen in clang code once).
* Should work for PR35877 and similar cases.
Cons:
* It assumes we have "main" scripts that describes sections.
Differential revision: https://reviews.llvm.org/D43468
llvm-svn: 327003
We don't need to handle an object file having more than one symbol table,
so as soon as we find the first one, we can process it and then return
from the function.
llvm-svn: 326977
When a symbol is exported via --export=foo but --allow-undefined
is also specified, the symbol is now allowed to be undefined.
Previously we were special casing such symbols.
This combinations of behavior is exactly what emescripten
requires. Although we are trying hard not to allow emscripten
specific features in lld, this one makes sense.
Enforce this behavior by added this case to test/wasm/undefined.ll.
Differential Revision: https://reviews.llvm.org/D44237
llvm-svn: 326976
addElfSymbols and readJustSymbolsFile still has duplicate code, but
I didn't come up with a good idea to eliminate them. Since this patch
is an improvement, I'm sending this for review.
Differential Revision: https://reviews.llvm.org/D44187
llvm-svn: 326972
Rui Ueyama