Summary:
Fixes PR35242. A simplified reproduce:
thread_local int i; int f() { return i; }
% {g++,clang++} -fPIC -shared -ftls-model=local-dynamic -fuse-ld=lld a.cc
ld.lld: error: can't create dynamic relocation R_X86_64_DTPOFF32 against symbol: i in readonly segment; recompile object files with -fPIC or pass '-Wl,-z,notext' to allow text relocations in the output
In isStaticLinkTimeConstant(), Syn.IsPreemptible is true, so it is not
seen as a constant. The error is then issued in processRelocAux().
A symbol of the local-dynamic TLS model cannot be preempted but it can
preempt symbols of the global-dynamic TLS model in other DSOs.
So it makes some sense that the variable is not static.
This patch fixes the linking error by changing getRelExpr() on
R_386_TLS_LDO_32 and R_X86_64_DTPOFF{32,64} from R_ABS to R_DTPREL.
R_PPC64_DTPREL_* and R_MIPS_TLS_DTPREL_* need similar fixes, but they are not handled in this patch.
As a bonus, we use `if (Expr == R_ABS && !Config->Shared)` to find
ld-to-le opportunities. R_ABS is overloaded here for such STT_TLS symbols.
A dedicated R_DTPREL is clearer.
Differential Revision: https://reviews.llvm.org/D60945
llvm-svn: 358870
Summary:
This relocation type is used by R_386_TLS_GD. Its formula is the same as
R_GOTPLT (e.g R_X86_64_GOT{32,64} R_386_TLS_GOTIE). Rename it to be clearer.
Differential Revision: https://reviews.llvm.org/D60941
llvm-svn: 358868
Summary:
The DataCount section is necessary for the bulk memory operations
memory.init and data.drop to validate, but it is not recognized by
engines that do not support bulk memory, so emit the section only if
bulk-memory is enabled.
Reviewers: aheejin, dschuff, sbc100
Subscribers: jgravelle-google, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60637
llvm-svn: 358798
Summary:
This assumes all symbols are <4GB long, so we can store them as a 32-bit
integer. This reorders the fields so the length appears first, packing
with the other bitfield data in the base Symbol object.
This saved 70MB / 3.60% of heap allocations when linking
browser_tests.exe with no PDB. It's not much as a percentage, but worth
doing. I didn't do performance measurements, I don't think it will be
measurable in time.
Reviewers: ruiu, inglorion, amccarth, aganea
Subscribers: llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60297
llvm-svn: 358794
Another attempt to land the changes in debug line header to prevent duplicate
files in Dwarf 5. I rolled back my previous commit because of a mistake in
generating the object file in a test. Meanwhile, I addressed some offline
comments and changed the implementation; the largest difference is that
MCDwarfLineTableHeader does not keep DwarfVersion but gets it as a parameter. I
also merged the patch to fix two lld tests that will strt to fail into this
patch.
Original Commit:
https://reviews.llvm.org/D59515
Original Message:
Motivation: In previous dwarf versions, file name indexes started from 1, and
the primary source file was not explicit. Dwarf 5 standard (6.2.4) prescribes
the primary source file to be explicitly given an entry with an index number 0.
The current implementation honors the specification by just duplicating the
main source file, once with index number 0, and later maybe with another
index number. While this is compliant with the letter of the standard, the
duplication causes problems for consumers of this information such as lldb.
(Some files are duplicated, where only some of them have a line table although
all refer to the same file)
With this change, dwarf 5 debug line section files always start from 0, and
the zeroth entry is not duplicated whenever possible. This requires different
handling of dwarf 4 and dwarf 5 during generation (e.g. when a function returns
an index zero for a file name, it signals an error in dwarf 4, but not in dwarf
5) However, I think the minor complication is worth it, because it enables all
consumers (lldb, gdb, dwarfdump, objdump, and so on) to treat all files in the
file name list homogenously.
llvm-svn: 358732
This is https://bugs.llvm.org//show_bug.cgi?id=39857.
I added the comment with much more details to the bug page,
the short version is below.
The following script and code demonstrates the issue:
aliasto__text = __text;
SECTIONS {
.text 0x1000 : { __text = . ; *(.text) }
}
...
call aliasto__text
LLD fails with "cannot refer to absolute symbol: aliasto__text" error.
It happens because at the moment of scanning the relocations
we do not yet assign the correct/final/any section value for the symbol aliasto__text.
I made a change to Relocations.cpp to fix that.
Also, I had to remove the symbol-location.s test case completely, because now it does not
trigger any error. Since now all linker scripts symbols are resolved to constants, no
errors can be triggered at all it seems. I checked that it is consistent with the behavior
of bfd and gold (they do not trigger errors for the case from symbol-location.s), so it should
be OK. I.e. at least it is probably not the best possible, but natural behavior we obtained.
Differential revision: https://reviews.llvm.org/D55423
llvm-svn: 358652
Summary:
If the output section contains only symbol assignments, we copy flags
from the previous sections. Don't set SHF_ALLOC if NonAlloc is true.
We also have to change the type from SHT_NOBITS to SHT_PROGBITS.
In ld.bfd, bfd_elf_get_default_section_type maps non-alloctable sections to SHT_PROGBITS.
Non-alloctable SHT_NOBITS sections do not make sense.
Fixes PR38626
Differential Revision: https://reviews.llvm.org/D59986
llvm-svn: 358650
This generalizes code and also fixes the broken behavior shown in
one of our test cases for some targets, like x86-64.
The issue occurs when the forward declarations are used in the script.
One of the samples is:
SECTIONS {
foo = ADDR(.text) - ABSOLUTE(ADDR(.text));
};
In that case, we have a broken output when output target does
not use thunks. That happens because thunks creating code
(called from maybeAddThunks)
calls Script->assignAddresses() at least one more time,
what fixups the values. As a result final symbols values can
be different on AArch64 and x86, for example.
In this patch, I generalize and rename maybeAddThunks to
finalizeAddressDependentContent and now it is used and called
by all targets.
Differential revision: https://reviews.llvm.org/D55550
llvm-svn: 358646
Summary:
We access Live and OutputOff (which may share the same memory location)
concurrently in 2 parallelForEachN loops. Separating them avoids subtle
data races like D41884/PR35788. This patch places Live and Hash
together.
2 reasons this is appealing:
1) Hash is immutable. Live is almost read-only - only written once in MarkLive.cpp where
Hash is not accessed
2) we already discard low bits of Hash to decide ShardID. It doesn't
matter much if we make 32-bit Hash to 31-bit.
For a huge internal clang -O3 executable (1.6GiB),
`Strings` in StringTableBuilder::finalizeStringTable contains at most 310253 elements.
The expected number of pair-wise collisions 2^(-31) * C(310253,2) ~= 22.41 is too small to have a negative impact on performance.
Actually, my benchmark shows there is actually a minor performance improvement.
Differential Revision: https://reviews.llvm.org/D60765
llvm-svn: 358645
Patch by Gabriel Smith.
The address for a section would be evaluated before the region was
switched to. Because of this, the position within the region would not
be updated. After the region is swapped to the dot would be set to the
out of date position within the region, undoing the section address
evaluation.
To fix this, the region is swapped to before the section's address is
evaluated. As part of the fallout of this, expandMemoryRegions needed
to be gated in setDot on the condition that the evaluated address is
less than the dot. This is for the case where sections are not listed
from lowest address to highest address.
Finally, a test for the case where sections are listed "out of order"
was added.
Differential Revision: https://reviews.llvm.org/D60744
llvm-svn: 358638
Patch by Nicholas Allegra.
The Mach-O writer calculates the size of load commands multiple times.
First, Util::assignAddressesToSections() (in MachONormalizedFileFromAtoms.cpp)
calculates the size using headerAndLoadCommandsSize() (in
MachONormalizedFileBinaryWriter.cpp), which creates a temporary
MachOFileLayout for the NormalizedFile, only to retrieve its
headerAndLoadCommandsSize. Later, writeBinary() (in
MachONormalizedFileBinaryWriter.cpp) creates a new layout and uses the offsets
from that layout to actually write out everything in the NormalizedFile.
But the NormalizedFile changes between the first computation and the second.
When Util::assignAddressesToSections is called, file.functionStarts is always
empty because Util::addFunctionStarts has not yet been called. Yet
MachOFileLayout decides whether to include a LC_FUNCTION_STARTS command based
on whether file.functionStarts is nonempty. Therefore, the initial computation
always omits it.
Because padding for the __TEXT segment (to make its size a multiple of the
page size) is added between the load commands and the first section, LLD still
generates a valid binary as long as the amount of padding happens to be large
enough to fit LC_FUNCTION_STARTS command, which it usually is.
However, it's easy to reproduce the issue by adding a section of a precise
size. Given foo.c:
__attribute__((section("__TEXT,__foo")))
char foo[0xd78] = {0};
Run:
clang -dynamiclib -o foo.dylib foo.c -fuse-ld=lld -install_name
/usr/lib/foo.dylib
otool -lvv foo.dylib
This should produce:
truncated or malformed object (offset field of section 1 in LC_SEGMENT_64
command 0 not past the headers of the file)
This commit:
- Changes MachOFileLayout to always assume LC_FUNCTION_STARTS is present for
the initial computation, as long as generating LC_FUNCTION_STARTS is
enabled. It would be slightly better to check whether there are actually
any functions, since no LC_FUNCTION_STARTS will be generated if not, but it
doesn't cause a problem if the initial computation is too high.
- Adds a test.
- Adds an assert in MachOFileLayout::writeSectionContent() that we are not
writing section content into the load commands region (which would happen
if the offset was calculated too low due to the initial load commands size
calculation being too low). Adds an assert in
MachOFileLayout::writeLoadCommands to validate a similar situation where
two size-of-load-commands computations are expected to be equivalent.
llvm-svn: 358545
With partitions, each partition should have the same build id. This means
that the build id needs to be only computed once, otherwise we will end up
with different build ids in each partition as a result of the file contents
changing. This change moves the computation of the build id into Writer so
that it only happens once.
Differential Revision: https://reviews.llvm.org/D60342
llvm-svn: 358536
Summary:
Archives can contain multiple members with the same name. This would
cause ThinLTO links to fail ("Expected at most one ThinLTO module per
bitcode file"). This change implements the same strategy we use in
the ELF linker: make the offset in the archive part of the module
name so that names are unique.
Reviewers: pcc, mehdi_amini, ruiu
Reviewed By: ruiu
Subscribers: eraman, steven_wu, dexonsmith, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60549
llvm-svn: 358440
When faced with command line options such as "crtbegin.o appmain.o
-lsomelib crtend.o", GNU ld pulls in all necessary object files from
somelib before proceeding to crtend.o.
LLD operates differently, only loading object files from any
referenced static libraries after processing all input object files.
This uses a similar hack as in the ELF linker. Here, it moves crtend.o
to the end of the vector of object files. This makes sure that
terminator chunks for sections such as .eh_frame gets ordered last,
fixing DWARF exception handling for libgcc and gcc's crtend.o.
Differential Revision: https://reviews.llvm.org/D60628
llvm-svn: 358394
The typo was introduced to llvm MC in rL204769 (fixed in rL358247) and then to lld.
Also, for relocatable-many-sections.s, the size of .symtab changed at some point and the formula needs update.
llvm-svn: 358248
Patch by Robert O'Callahan.
Rust projects tend to link in all object files from all dependent
libraries and rely on --gc-sections to strip unused code and data.
Unfortunately --gc-sections doesn't currently strip any debuginfo
associated with GC'ed sections, so lld links in the full debuginfo from
all dependencies even if almost all that code has been discarded. See
https://github.com/rust-lang/rust/issues/56068 for some details.
Properly stripping debuginfo for discarded sections would be difficult,
but a simple approach that helps significantly is to mark debuginfo
sections as live only if their associated object file has at least one
live code/data section. This patch does that. In a (contrived but not
totally artificial) Rust testcase linked above, it reduces the final
binary size from 46MB to 5.1MB.
Differential Revision: https://reviews.llvm.org/D54747
llvm-svn: 358069
Previously the tests in lld for RISC-V were given in yaml format as
LLVM's RISC-V assembler support was incomplete. Now that the
assembler/disassembler has matured we can rewrite all tests to use
LLVM's tools.
Differential Revision: https://reviews.llvm.org/D60415
llvm-svn: 357996
The code previously specified a 32-bit range for R_RISCV_HI20 and
R_RISCV_LO12_[IS], however this is incorrect as the maximum offset on
RV64 that can be formed from the immediate of lui and the displacement
of an I-type or S-type instruction is -0x80000800 to 0x7ffff7ff. There
is also the same issue with a c.lui and LO12 pair, whose actual
addressable range should be -0x20800 to 0x1f7ff.
The tests will be included in the next patch that converts all RISC-V
tests to use llvm-mc instead of yaml2obj, as assembler support has
matured enough to write tests in them.
Differential Revision: https://reviews.llvm.org/D60414
llvm-svn: 357995
For partitions I intend to use the same set of version indexes in
each partition for simplicity. Since each partition will need its own
VersionNeedSection this will require moving the verneed tracking out of
VersionNeedSection. The way I've done this is to move most of the tracking
into SharedFile. What will eventually become the per-partition tracking
still lives in VersionNeedSection.
As a bonus the code gets a little simpler and more consistent with how we
handle verdef.
Differential Revision: https://reviews.llvm.org/D60307
llvm-svn: 357926
Previously, we drop symbols starting with .L from the symbol table, so
if there is a relocation that refers a .L symbol, it ended up
referencing a null -- which happened to be interpreted as an absolute
symbol.
This patch copies all symbols including local ones if -emit-reloc is
given.
Fixes https://bugs.llvm.org/show_bug.cgi?id=41385
Differential Revision: https://reviews.llvm.org/D60306
llvm-svn: 357885
This should have been part of rL357710 but was overlooked because
in our test code the function in question was also used in other
relocations that caused it to be added to the table anyway.
Differential Revision: https://reviews.llvm.org/D60296
llvm-svn: 357737
Summary:
Take the Index into account in `getDelayImportTable`, otherwise we
always return the entry for the first delay DLL reference.
Reviewers: ruiu
Reviewed By: ruiu
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60081
llvm-svn: 357697
Summary:
Now CVType and CVSymbol are effectively type-safe wrappers around
ArrayRef<uint8_t>. Make the kind() accessor load it from the
RecordPrefix, which is the same for types and symbols.
Reviewers: zturner, aganea
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60018
llvm-svn: 357658
Summary:
Reorder the fields in both to use padding more efficiently, and add more
comments on the purpose of the fields.
Replace `std::vector<SectionChunk*> AssociativeChildren` with a
singly-linked list. This avoids the separate vector allocation to list
associative children, and shrinks the 3 pointers used for the typically
empty vector down to 1.
In the end, this reduces the sum of heap allocations used to link
browser_tests.exe with NO PDB by 13.10%, going from 2,248,728 KB to
1,954,071 KB of heap. These numbers exclude memory mapped files, which
are of course a significant factor in LLD's memory usage.
Reviewers: ruiu, mstorsjo, aganea
Subscribers: jdoerfert, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59797
llvm-svn: 357535
Introduce a new TypeMerger class, out of some type-merge-specific structures from PDB.cpp
No changes intended / this is only moving code around.
This patch is step 3. in "Proposed commit strategy" in D59226
Differential Revision: https://reviews.llvm.org/D60070
llvm-svn: 357525
And rename the function to combineEhSections(). This makes the processing
of .ARM.exidx even more similar to .eh_frame and means that we can avoid an
additional loop over InputSections.
Differential Revision: https://reviews.llvm.org/D60026
llvm-svn: 357417
We introduce a new class hierarchy for debug types merging (in DebugTypes.h). The end-goal is to parallelize the type merging - please see the plan in D59226.
Previously, dependency discovery was done on the fly, much later, during the type merging loop. Unfortunately, parallelizing the type merging requires the dependencies to be merged in first, before any dependent ObjFile, thus this early discovery.
The overall intention for this path is to discover debug information dependencies at a much earlier stage, when processing input files. Currently, two types of dependency are supported: PDB type servers (when compiling with MSVC /Zi) and precompiled headers OBJs (when compiling with MSVC /Yc and /Yu). Once discovered, an explicit link is added into the dependent ObjFile, through the new debug types class hierarchy introduced in DebugTypes.h.
Differential Revision: https://reviews.llvm.org/D59053
llvm-svn: 357383
Summary:
Some synthetic sections can be empty while still being needed, thus they
can't be removed by removeUnusedSyntheticSections(). Rename this member
function to more appropriate isNeeded() with the opposite meaning.
No functional change intended.
Reviewers: ruiu, espindola
Reviewed By: ruiu
Subscribers: jhenderson, grimar, emaste, arichardson, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59982
llvm-svn: 357377
See https://reviews.llvm.org/D59860
The initial version of this change effected more than just the
error message. This version is scoped down to only effect the error
itself.
llvm-svn: 357328
Summary:
Makes it a linker error if the "atomics" feature is used but the user
does not opt in to shared memory or if "atomics" is disallowed but the
user does opt in to shared memory. Also check that an appropriate max
memory size is supplied if shared memory is used.
Reviewers: sbc100, aheejin
Subscribers: dschuff, jgravelle-google, sunfish, jfb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59281
llvm-svn: 357310
Generate import modules for each imported DLL, along with its symbol stream.
Also create COFF groups in the * Linker * module, one for each PartialSection (input, unmerged sections)
Currently COFF groups are disabled for MINGW because it significantly increases PDB sizes. We could enable that later with an option.
The overall objective for this change is to support code hot patching tools. Such tools need to know the import libraries used, from the PDB alone.
Differential Revision: https://reviews.llvm.org/D54802
llvm-svn: 357308
Also Revert "[WebAssembly] Fix typo from rL357143"
This reverts commit 0805ec5f7b and
a9958fc30d
(rL357143 and rL357144)
They cause failures with address-taken extern (JS) functions
in emscripten.
llvm-svn: 357224
Summary:
This avoids allocating O(#relocs) of intermediate data for each section
when range extension thunks aren't needed for that section. This also
removes a std::vector from SectionChunk, which further reduces its size.
Instead, this change adds the range extension thunk symbols to the
object files that contain sections that need extension thunks. By adding
them to the symbol table of the parent object, that means they now have
a symbol table index. Then we can then modify the original relocation,
after copying it to read-write memory, to use the new symbol table
index.
This makes linking browser_tests.exe with no PDB 10.46% faster, moving
it from 11.364s to 10.288s averaged over five runs.
Reviewers: mstorsjo, ruiu
Subscribers: aganea, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59902
llvm-svn: 357200
This change itself doesn't mean anything, but it helps D59780 because
in patch, we don't know whether we need to create a CET-aware PLT or
not until we read all input files.
llvm-svn: 357194
Recommit r356666 with fixes for buildbot failure, as well as handling for
--emit-relocs, which we decide not to emit any relocation sections as the
table is already position independent and an offline tool can deduce the
relocations.
Instead of creating extra Synthetic .ARM.exidx sections to account for
gaps in the table, create a single .ARM.exidx SyntheticSection that can
derive the contents of the gaps from a sorted list of the executable
InputSections. This has the benefit of moving the ARM specific code for
SyntheticSections in SHF_LINK_ORDER processing and the table merging code
into the ARM specific SyntheticSection. This also makes it easier to create
EXIDX_CANTUNWIND table entries for executable InputSections that don't
have an associated .ARM.exidx section.
Fixes pr40277
Differential Revision: https://reviews.llvm.org/D59216
llvm-svn: 357160
Patch by Tiancong Wang.
In D36351, Call-Chain Clustering (C3) heuristic is implemented with
option --call-graph-ordering-file <file>.
This patch adds a flag --print-symbol-order=<file> to LLD, and when
specified, it prints out the symbols ordered by the heuristics to the
file. The symbols printout is helpful to those who want to understand
the heuristics and want to reproduce the ordering with
--symbol-ordering-file in later pass.
Differential Revision: https://reviews.llvm.org/D59311
llvm-svn: 357133
No longer require workarounds for output to "-" (stdout) for
Windows. These workarounds were just hiding the actual problem which has
been fixed in r357058.
Differential Revision: https://reviews.llvm.org/D59824
llvm-svn: 357072
This reverts commit rL357020
Reason: rL357018, which this commit depend on breaks the test:
llvm/test/tools/llvm-objdump/embedded-source.test on some architectures.
llvm-svn: 357025
This change implements lowering of references global symbols in PIC
mode.
This change implements lowering of global references in PIC mode using a
new @GOT reference type. @GOT references can be used with function or
data symbol names combined with the get_global instruction. In this case
the linker will insert the wasm global that stores the address of the
symbol (either in memory for data symbols or in the wasm table for
function symbols).
For now I'm continuing to use the R_WASM_GLOBAL_INDEX_LEB relocation
type for this type of reference which means that this relocation type
can refer to either a global or a function or data symbol. We could
choose to introduce specific relocation types for GOT entries in the
future. See the current dynamic linking proposal:
https://github.com/WebAssembly/tool-conventions/blob/master/DynamicLinking.md
Differential Revision: https://reviews.llvm.org/D54647
llvm-svn: 357022
Reapply rL356943; the previous attempt was reverted because the patch rL356941
that this depended on had broken a test.
Original commit message:
[lld] Prevent duplicate files in debug line header in dwarf 5.
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59671
llvm-svn: 357020
Do not pipe binary data between processes in lit tests this time,
since it turns out that can break on Windows.
This reverts commit 84c8652fc3.
llvm-svn: 356975
Summary:
This should address remaining issues discussed in PR36555.
Currently R_GOT*_FROM_END are exclusively used by x86 and x86_64 to
express relocations types relative to the GOT base. We have
_GLOBAL_OFFSET_TABLE_ (GOT base) = start(.got.plt) but end(.got) !=
start(.got.plt)
This can have problems when _GLOBAL_OFFSET_TABLE_ is used as a symbol, e.g.
glibc dl_machine_dynamic assumes _GLOBAL_OFFSET_TABLE_ is start(.got.plt),
which is not true.
extern const ElfW(Addr) _GLOBAL_OFFSET_TABLE_[] attribute_hidden;
return _GLOBAL_OFFSET_TABLE_[0]; // R_X86_64_GOTPC32
In this patch, we
* Change all GOT*_FROM_END to GOTPLT* to fix the problem.
* Add HasGotPltOffRel to denote whether .got.plt should be kept even if
the section is empty.
* Simplify GotSection::empty and GotPltSection::empty by setting
HasGotOffRel and HasGotPltOffRel according to GlobalOffsetTable early.
The change of R_386_GOTPC makes X86::writePltHeader simpler as we don't
have to compute the offset start(.got.plt) - Ebx (it is constant 0).
We still diverge from ld.bfd (at least in most cases) and gold in that
.got.plt and .got are not adjacent, but the advantage doing that is
unclear.
Reviewers: ruiu, sivachandra, espindola
Subscribers: emaste, mehdi_amini, arichardson, dexonsmith, jdoerfert, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59594
llvm-svn: 356968
lld's mark-sweep garbage collector was written in the visitor pattern.
There are functions that traverses a given graph, and the functions calls
callback functions to dispatch according to node type.
The code was originaly pretty simple, and lambdas worked pretty
well. However, as we add more features to the garbage collector, that became
more like a callback hell. We now have a callback function that wraps
another callback function, for example. It is not easy to follow the flow of
the control.
This patch rewrites it as a regular class. What was once a lambda is now a
regular class member function. I think this change fixes the readability
issue.
No functionality change intended.
Differential Revision: https://reviews.llvm.org/D59800
llvm-svn: 356966
Summary:
Changes to a couple of tests that will start failing after https://reviews.llvm.org/D59515 is submitted.
Reviewers: echristo, ruiu, espindola
Reviewed By: echristo, ruiu
Subscribers: emaste, arichardson, MaskRay, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59671
llvm-svn: 356943
Take module DBI creation out of PDBLinker::addObjFile() into its own function.
This is groundwork towards parallelizable type merging, as proposed in D59226.
Differential Revision: https://reviews.llvm.org/D59261
llvm-svn: 356815
Previously, `Entries` contains pairs of symbols and their indices.
The indices are always 0, x, 2x, 3x, ..., where x is the size of
relocation entry. We didn't have to store that values because we can
compute them when we consume them.
llvm-svn: 356812
Summary:
Adds --check-features and --no-check-features. The default for now is
to enable the checking, but this might change in the future.
Also adds --features=foo,bar for precisely controlling the features
used in the output binary.
Depends on D59173.
Reviewers: sbc100, aheejin
Subscribers: dschuff, jgravelle-google, sunfish, jdoerfert, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59274
llvm-svn: 356805
There is a reproducible buildbot failure (segfault) on the 2 stage
clang-cmake-armv8-lld bot. Reverting while I investigate.
Differential Revision: https://reviews.llvm.org/D59216
llvm-svn: 356684
Instead of creating extra Synthetic .ARM.exidx sections to account for
gaps in the table, create a single .ARM.exidx SyntheticSection that can
derive the contents of the gaps from a sorted list of the executable
InputSections. This has the benefit of moving the ARM specific code for
SyntheticSections in SHF_LINK_ORDER processing and the table merging code
into the ARM specific SyntheticSection. This also makes it easier to create
EXIDX_CANTUNWIND table entries for executable InputSections that don't
have an associated .ARM.exidx section.
Fixes pr40277
Differential Revision: https://reviews.llvm.org/D59216
llvm-svn: 356666
Summary:
Implements a new target features section in assembly and object files
that records what features are used, required, and disallowed in
WebAssembly objects. The linker uses this information to ensure that
all objects participating in a link are feature-compatible and records
the set of used features in the output binary for use by optimizers
and other tools later in the toolchain.
The "atomics" feature is always required or disallowed to prevent
linking code with stripped atomics into multithreaded binaries. Other
features are marked used if they are enabled globally or on any
function in a module.
Future CLs will add linker flags for ignoring feature compatibility
checks and for specifying the set of allowed features, implement using
the presence of the "atomics" feature to control the type of memory
and segments in the linked binary, and add front-end flags for
relaxing the linkage policy for atomics.
Reviewers: aheejin, sbc100, dschuff
Subscribers: jgravelle-google, hiraditya, sunfish, mgrang, jfb, jdoerfert, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59173
llvm-svn: 356610
D58391 changed the LTO pipelines to add the tailcall elimination pass.
This caused three LLD tests to fail.
Differential Revision: https://reviews.llvm.org/D59604
llvm-svn: 356593
This should be the only change required to have lld's python code base compatible with both Python 2 and Python 3
Differential Revision: https://reviews.llvm.org/D59538
llvm-svn: 356538
Summary:
This implements Rui Ueyama's idea in PR39044.
I've checked that ld.bfd and gold do not have the power-of-2 requirement
and do not require sh_entsize to be a multiple of sh_align.
Now on the updated test merge-entsize.s, all the 3 linkers happily
create .rodata that is not 3-byte aligned.
This has a use case in Linux arch/x86/crypto/sha512-avx2-asm.S
It uses sh_entsize of 640, which is not a power of 2.
See https://github.com/ClangBuiltLinux/linux/issues/417
Reviewers: ruiu, espindola
Reviewed By: ruiu
Subscribers: nickdesaulniers, E5ten, emaste, arichardson, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59478
llvm-svn: 356428
Before, empty debug streams were written as 8 bytes (4 bytes signature + 4 bytes for the GlobalRefs count).
With this patch, unused empty streams aren't emitted anymore. Modules now encode 65535 as an 'unused stream' value, by convention.
Also fix the * Linker * contrib section which wasn't correctly emitted previously.
Differential Revision: https://reviews.llvm.org/D59502
llvm-svn: 356395
It seems to pass fine on my Mac, and it running it only on Windows made
me miss it in r355959 and required r355959.
When the test was added in r288992 we still used Win-only
UnDecorateSymbolName() for demangling. Now we use LLVM's
microsoftDemangle() which is cross-platform.
Differential Revision: https://reviews.llvm.org/D59497
llvm-svn: 356380
For these types of relocations an absolute memory address is
required which is not possible for undefined data symbols. For symbols
that can be undefined at link time (i.e. external data symbols in
shared libraries) a different type of relocation (i.e. via a GOT) will
be needed.
Differential Revision: https://reviews.llvm.org/D59337
llvm-svn: 356310
arm-plt-reloc.s arm-thumb-plt-reloc.s: update offset calculations
pack-dyn-relocs-loop.s: this test is very sensitive to exact section
offsets and sizes. If we comment out the following two lines in
SyntheticSections.cpp, we should reproduce `ld.lld: error: thunk
creation not converged` caused by oscillation of the section size.
if (RelocData.size() < OldSize)
RelocData.append(OldSize - RelocData.size(), 0);
Use -z norelro to counteract the layout change (to be more specific,
we have to place .dynamic below .foo so that offset(foo) remains 0x10004)
llvm-svn: 356229
Summary:
Based on Peter Collingbourne's suggestion in D56828.
Before D56828: PT_LOAD(.data PT_GNU_RELRO(.data.rel.ro .bss.rel.ro) .bss)
Old: PT_LOAD(PT_GNU_RELRO(.data.rel.ro .bss.rel.ro) .data .bss)
New: PT_LOAD(PT_GNU_RELRO(.data.rel.ro .bss.rel.ro)) PT_LOAD(.data. .bss)
The new layout reflects the runtime memory mappings.
By having two PT_LOAD segments, we can utilize the NOBITS part of the
first PT_LOAD and save bytes for .bss.rel.ro.
.bss.rel.ro is currently small and only used by copy relocations of
symbols in read-only segments, but it can be used for other purposes in
the future, e.g. if a relro section's statically relocated data is all
zeros, we can move it to .bss.rel.ro.
Reviewers: espindola, ruiu, pcc
Reviewed By: ruiu
Subscribers: nemanjai, jvesely, nhaehnle, javed.absar, kbarton, emaste, arichardson, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58892
llvm-svn: 356226
/summary prints information about the data (OBJ/LIB/PDB) processed by LLD. The goal is have an estimate about the inputs and outputs, to better understand where the timings go.
Differential Revision: https://reviews.llvm.org/D58599
llvm-svn: 356188
We allow an archive file without symbol table as a linker input as a
workaround for a very common error in LTO build. But that logic worked
even for an archive file containing non-bitcode files, which is not
expected. This patch limits that workaround to one that contains only
bitcode files.
Differential Revision: https://reviews.llvm.org/D59373
llvm-svn: 356186
Old: PT_LOAD(.data | PT_GNU_RELRO(.data.rel.ro .bss.rel.ro) | .bss)
New: PT_LOAD(PT_GNU_RELRO(.data.rel.ro .bss.rel.ro) | .data .bss)
The placement of | indicates page alignment caused by PT_GNU_RELRO. The
new layout has simpler rules and saves space for many cases.
Old size: roundup(.data) + roundup(.data.rel.ro)
New size: roundup(.data.rel.ro + .bss.rel.ro) + .data
Other advantages:
* At runtime the 3 memory mappings decrease to 2.
* start(PT_TLS) = start(PT_GNU_RELRO) = start(RW PT_LOAD). This
simplifies binary manipulation tools.
GNU strip before 2.31 discards PT_GNU_RELRO if its
address is not equal to the start of its associated PT_LOAD.
This has been fixed by https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=f2731e0c374e5323ce4cdae2bcc7b7fe22da1a6f
But with this change, we will be compatible with GNU strip before 2.31
* Before, .got.plt (non-relro by default) was placed before .got (relro
by default), which made it impossible to have _GLOBAL_OFFSET_TABLE_
(start of .got.plt on x86-64) equal to the end of .got (R_GOT*_FROM_END)
(https://bugs.llvm.org/show_bug.cgi?id=36555). With the new ordering, we
can improve on this regard if we'd like to.
Reviewers: ruiu, espindola, pcc
Subscribers: emaste, arichardson, llvm-commits, joerg, jdoerfert
Differential Revision: https://reviews.llvm.org/D56828
llvm-svn: 356117
When linking shared libraries, we import a mutable wasm global
to represent the address of each undefined data symbol.
This is a step towards supporting dynamic linking and shared
libraries.
Differential Revision: https://reviews.llvm.org/D59270
llvm-svn: 355988
Currently we have -Rpass for filtering the remarks that are displayed as
diagnostics, but when using -fsave-optimization-record, there is no way
to filter the remarks while generating them.
This adds support for filtering remarks by passes using a regex.
Ex: `clang -fsave-optimization-record -foptimization-record-passes=inline`
will only emit the remarks coming from the pass `inline`.
This adds:
* `-fsave-optimization-record` to the driver
* `-opt-record-passes` to cc1
* `-lto-pass-remarks-filter` to the LTOCodeGenerator
* `--opt-remarks-passes` to lld
* `-pass-remarks-filter` to llc, opt, llvm-lto, llvm-lto2
* `-opt-remarks-passes` to gold-plugin
Differential Revision: https://reviews.llvm.org/D59268
Original llvm-svn: 355964
llvm-svn: 355984
This does not appear to be necessary because StringTableSection does not
need to be finalized, which also means that we can remove the call to
finalizeSynthetic on .dynstr.
Differential Revision: https://reviews.llvm.org/D59240
llvm-svn: 355977
This shaves another word off SectionBase and makes it possible to clone a
section using the implicit copy constructor.
This basically reverts r311056, which removed the mutex in order to
make the code easier to understand. On balance I think it's probably more
straightforward to have a mutex here than to have an unusual copy constructor
in SectionBase.
Differential Revision: https://reviews.llvm.org/D59269
llvm-svn: 355966
Currently we have -Rpass for filtering the remarks that are displayed as
diagnostics, but when using -fsave-optimization-record, there is no way
to filter the remarks while generating them.
This adds support for filtering remarks by passes using a regex.
Ex: `clang -fsave-optimization-record -foptimization-record-passes=inline`
will only emit the remarks coming from the pass `inline`.
This adds:
* `-fsave-optimization-record` to the driver
* `-opt-record-passes` to cc1
* `-lto-pass-remarks-filter` to the LTOCodeGenerator
* `--opt-remarks-passes` to lld
* `-pass-remarks-filter` to llc, opt, llvm-lto, llvm-lto2
* `-opt-remarks-passes` to gold-plugin
Differential Revision: https://reviews.llvm.org/D59268
llvm-svn: 355964
We don't need to take a slice of SectionCommands in addOrphanSections()
because it is not modified until the end of the function.
Differential Revision: https://reviews.llvm.org/D59239
llvm-svn: 355954
On Darwin targets, llvm-ar creates a Darwin format archive by default,
which ld.lld can't read, so it was printing an unexpected error.
llvm-svn: 355894
This makes lld-link's output a bit more concise. Since most developers can't
read mangled names, this should make the output a bit easier to understand as
well. It also makes lld-link's output consistent with ld.lld's output.
(link.exe prints both demangled and mangled names; lld-link used to match
link.exe output but now no longer does.)
For people working on toolchains, add a `/demangle:no` flag that makes lld-link
print the mangled name instead of the demangled name. (If desired, people could
pipe that through `demumble -b` to get the old behavior of both demangled and
mangled output.)
Differential Revision: https://reviews.llvm.org/D58132
llvm-svn: 355878
This unit test fails if 'zed' appears in your build path, as lld is
echoing out the path of the source file. Change the unit test to
explicitly only match everything after the 'Symbols [' line of the
output, to make sure that this test doesn't inadvertently fail due to
the build path.
llvm-svn: 355748
This matches the ELF does. Update the comment in ELF/Symbols.h and
duplicate it in wasm/Symbols.h
This a followup on rL355580 and rL355577.
Differential Revision: https://reviews.llvm.org/D59075
llvm-svn: 355737
- The Assigned bit was previously taking a word on its own. Move
it into the bit fields in SectionBase.
- NumRelocations and AreRelocsRela were previously also taking up
a word despite only using half of it. Move them into the alignment gap
after SectionBase's fields.
Differential Revision: https://reviews.llvm.org/D59044
llvm-svn: 355622
When mismatched #pragma detect_mismatch declarations occur, now print the conflicting OBJs.
lld-link: error: /failifmismatch: mismatch detected for 'TEST':
>>> test.obj has value 1
>>> test2.obj has value 2
Fixes PR38579
Differential Revision: https://reviews.llvm.org/D58910
llvm-svn: 355543
We're going to need a separate VersionNeedSection for each partition, and
the partition data structure won't be templated.
With this the VersionTableSection class no longer needs ELFT, so detemplate it.
Differential Revision: https://reviews.llvm.org/D58808
llvm-svn: 355478
Summary:
We disabled MachineBlockPlacement pass in D58953, and this test result
changes as the result of it.
Reviewers: kripken
Subscribers: dschuff, sbc100, jgravelle-google, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58954
llvm-svn: 355438
If the permission does not permit writing and the standard input is a
terminal, rm gives an annoying prompt. chmod u+w to make the output
directory easier to delete.
llvm-svn: 355382
This lets us detect file size overflows when creating a 64-bit binary on
a 32-bit machine.
Differential Revision: https://reviews.llvm.org/D58840
llvm-svn: 355218
r355153 introduced a build failure on a build bot that uses clang natively
on an armv7-a machine. This a temporary fix to use size_t rather than
uint64_t.
llvm-svn: 355195
This lets us remove the special case from Writer::writeSections(), and also
fixes a bug where .eh_frame_hdr isn't necessarily written in the correct
order if a linker script moves .eh_frame and .eh_frame_hdr into the same
output section.
Differential Revision: https://reviews.llvm.org/D58795
llvm-svn: 355153
Summary:
In the clang UI, replaces -mthread-model posix with -matomics as the
source of truth on threading. In the backend, replaces
-thread-model=posix with the atomics target feature, which is now
collected on the WebAssemblyTargetMachine along with all other used
features. These collected features will also be used to emit the
target features section in the future.
The default configuration for the backend is thread-model=posix and no
atomics, which was previously an invalid configuration. This change
makes the default valid because the thread model is ignored.
A side effect of this change is that objects are never emitted with
passive segments. It will instead be up to the linker to decide
whether sections should be active or passive based on whether atomics
are used in the final link.
Reviewers: aheejin, sbc100, dschuff
Subscribers: mehdi_amini, jgravelle-google, hiraditya, sunfish, steven_wu, dexonsmith, rupprecht, jfb, jdoerfert, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D58742
llvm-svn: 355112
That patch is the fix for https://bugs.llvm.org/show_bug.cgi?id=40703
"wrong line number info for obj file compiled with -ffunction-sections"
bug. The problem happened with only .o files. If object file contains
several .text sections then line number information showed incorrectly.
The reason for this is that DwarfLineTable could not detect section which
corresponds to specified address(because address is the local to the
section). And as the result it could not select proper sequence in the
line table. The fix is to pass SectionIndex with the address. So that it
would be possible to differentiate addresses from various sections. With
this fix llvm-objdump shows correct line numbers for disassembled code.
Differential review: https://reviews.llvm.org/D58194
llvm-svn: 354972
This patch removes the precompiled binary from inputs,
replacing it with a YAML. And teaches LLD to report a
section name in case of such error.
Differential revision: https://reviews.llvm.org/D58670
llvm-svn: 354959
Summary:
The gold linker allowed you to output the ELF files after LTO was run. It did
it by using the 'obj-path' option. This replicates that behavior.
Reviewers: espindola, ruiu, MaskRay, pcc
Reviewed By: MaskRay, pcc
Subscribers: grimar, emaste, inglorion, arichardson, steven_wu, dexonsmith, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D56046
llvm-svn: 354917
The linux kernel uses an old flag -p/-no-pipeline-knowledge that is
accepted by bfd and gold but ignored by modern versions of them. The
original option is very old and is pre-ABI, it sometimes comes up in
code-bases that had support for pre ABI toolchains. The Linux kernel uses
it in 3 places in the ARM specific section.
Differential Revision: https://reviews.llvm.org/D58540
llvm-svn: 354769
yaml2obj used to require the Symbol field in relocations, but it hasn't
done so for a couple of years. Another change to yaml2obj will soon land
that will look up the symbol by name or index, if present, and emit an
error if not found. This will mean that an explicit symbol reference
(even to an empty-named symbol) that does not reference a symbol
declared in the yaml will result in an error.
This patch updates tests that would otherwise start emitting errors.
Reviewed by: ruiu, grimar
Differential Revision: https://reviews.llvm.org/D58508
llvm-svn: 354666
RelocationBaseSection is not used in -r links, so Config->Relocatable will
always be false.
Differential Revision: https://reviews.llvm.org/D58489
llvm-svn: 354607
The code for encoding the symbols signature into its name
was not actually being used in the final version of this change.
Differential Revision: https://reviews.llvm.org/D58482
llvm-svn: 354539
Previously we could emit a warning and generate a potentially invalid
wasm module (due to call sites and functions having conflicting
signatures). Now, rather than create invalid binaries we handle such
cases by creating stub functions containing unreachable, effectively
turning these into runtime errors rather than validation failures.
Differential Revision: https://reviews.llvm.org/D57909
llvm-svn: 354528
Three MIPS-specific sections `.reginfo`, `.MIPS.options`, and `.MIPS.abiflags`
are used by loader to read their contents and setup environment for running
a program. Loader looks up these data in the corresponding segments:
`PT_MIPS_REGINFO`, `PT_MIPS_OPTIONS`, and `PT_MIPS_ABIFLAGS` respectively.
This patch put these sections to separate segments like we do already
for ARM `SHT_ARM_EXIDX` section.
Differential Revision: http://reviews.llvm.org/D58381
llvm-svn: 354468
Summary:
We translate @llvm.used to COFF by generating /include directives
in the .drectve section. However, in LTO links, this happens after
directives have already been processed, so the new directives do
not take effect. This change marks @llvm.used symbols as GCRoots
so that they are preserved as intended.
Fixes PR40733.
Reviewers: rnk, pcc, ruiu
Reviewed By: ruiu
Subscribers: mehdi_amini, steven_wu, dexonsmith, dang, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58255
llvm-svn: 354410
Summary:
Rename MemoryIndex to InitFlags and implement logic for determining
data segment layout in ObjectYAML and MC. Also adds a "passive" flag
for the .section assembler directive although this cannot be assembled
yet because the assembler does not support data sections.
Reviewers: sbc100, aardappel, aheejin, dschuff
Subscribers: jgravelle-google, hiraditya, sunfish, rupprecht, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D57938
llvm-svn: 354397
This is a private undocumented option, intended to be used by
the MinGW driver frontend.
Also restructure the condition to put if (Config->MinGW) first.
This changes the behaviour for the tautological combination of
-export-all-symbols without -lldmingw.
Differential Revision: https://reviews.llvm.org/D58380
llvm-svn: 354386
MIPS R6 code uses the `R_MIPS_PC26_S2` relocation for calls which might
cross boundaries of non-PIC-to-PIC code. We need to create a LA25 thunks
for that case.
llvm-svn: 354312
The patch solves two tasks:
1. MIPS ABI allows to mix regular and microMIPS code and perform
cross-mode jumps. Linker needs to detect such cases and replace
jump/branch instructions by their cross-mode equivalents.
2. Other tools like dunamic linkers need to recognize cases when dynamic
table entries, e_entry field of an ELF header etc point to microMIPS
symbol. Linker should provide such information.
The first task is implemented in the `MIPS<ELFT>::relocateOne()` method.
New routine `fixupCrossModeJump` detects ISA mode change, checks and
replaces an instruction.
The main problem is how to recognize that relocation target is microMIPS
symbol. For absolute and section symbols compiler or assembler set the
less-significant bit of the symbol's value or sum of the symbol's value
and addend. And this bit signals to linker about microMIPS code. For
global symbols compiler cannot do the same trick because other tools like,
for example, disassembler wants to know an actual position of the symbol.
So compiler sets STO_MIPS_MICROMIPS flag in the `st_other` field.
In `MIPS<ELFT>::relocateOne()` method we have a symbol's value only and
cannot access any symbol's attributes. To pass type of the symbol
(regular/microMIPS) to that routine as well as other places where we
write a symbol value as-is (.dynamic section, `Elf_Ehdr::e_entry` field
etc) we set when necessary a less-significant bit in the `getSymVA`
function.
Differential revision: https://reviews.llvm.org/D40147
llvm-svn: 354311
On PowerPC64, it is necessary to keep the LocalEntry bits in st_other,
especially when -r is used. Otherwise, when the resulting object is used
in a posterior linking, LocalEntry info will be unavailable and
functions may be called through the wrong entrypoint.
Patch by Leandro Lupori.
Differential Revision: https://reviews.llvm.org/D56782
llvm-svn: 354184
Summary:
So this patch just make sure that the thread is at least stated
before we return from main.
If we just detach then the thread may be actually be stated just after
the process returned from main and it's calling atexit handers. Then the thread may try to create own function static variable and it will
add new at exit handlers confusing libc.
GLIBC before 2.27 had race in that case which corrupted atexit handlers
list. Support for this use-case for other implementation is also unclear,
so we can try just avoid that.
PR40162
Reviewers: ruiu, espindola
Subscribers: emaste, arichardson, jfb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58246
llvm-svn: 354078
Previously, we showed the following message for an unknown relocation:
foo.o: unrecognized reloc 256
This patch improves it so that the error message includes a symbol name:
foo.o: unknown relocation (256) against symbol bar
llvm-svn: 354040
Turns out nobody understands what "conflicting comdat type" is supposed to
mean, so just emit a regular "duplicate symbol" error and move the comdat
selection information into /verbose output.
This also fixes a problem where the error output would depend on the order of
.obj files passed. Before this patch:
- If passed `one_only.obj discard.obj`, lld-link would only err "conflicting
comdat type"
- If passed `discard.obj one_only.obj`, lld-link would err "conflicting comdat
type" and then "duplicate symbol"
Now lld-link only errs "duplicate symbol" in both cases.
I considered adding a "Detail" parameter to reportDuplicate() that's printed in
parens at the end of the "duplicate symbol" diag if present, and then put the
comdat selection mismatch details there, but since users don't know what it's
supposed to mean decided against it. I also considered special-casing the
Detail message for one_only/discard mismatches, which in practice means
"function defined as inline in TU 1 but as out-of-line in TU 2", but I wasn't
sure how useful it is so I omitted that too.
Differential Revision: https://reviews.llvm.org/D58180
llvm-svn: 354006
Non-GOT non-PLT relocations to non-preemptible ifuncs result in the
creation of a canonical PLT, which now takes the identity of the IFUNC
in the symbol table. This (a) ensures address consistency inside and
outside the module, and (b) fixes a bug where some of these relocations
end up pointing to the resolver.
Fixes (at least) PR40474 and PR40501.
Differential Revision: https://reviews.llvm.org/D57371
llvm-svn: 353981
This fixes a 7.0 -> 8.0 regression when parsing
OUTPUT_FORMAT("elf32-powerpc"); or elf32-bigmips directive in ldscripts
as well as an unknown emulation error when lld is invoked by clang due
to missed elf32ppclinux case.
Patch by vit9696
Differential Revision: https://reviews.llvm.org/D58005
llvm-svn: 353968
Previously, we validated -z options after we process --version or --help flags.
So, if one of these flags is given, we wouldn't show an "unknown -z option"
error. This patch fixes that behavior.
Differential Revision: https://reviews.llvm.org/D55446
llvm-svn: 353967
The printing of branch operands for call instructions was changed to properly
handle negative offsets. Updating the tests to reflect that.
llvm-svn: 353866
A follow up to the intial patch that unblocked linking against libgcc.
For lld we don't need to bother tracking which objects have got based small
code model relocations. This is due to the fact that the compilers on
powerpc64 use the .toc section to generate indirections to symbols (rather then
using got relocations) which keeps the got small. This makes overflowing a
small code model got relocation very unlikely.
Differential Revision: https://reviews.llvm.org/D57245
llvm-svn: 353849
gold accepts quoted strings. binutils requires quoted strings for some
kinds of symbols, e.g.:
it accepts quoted symbols with @ in name:
$ echo 'EXTERN("__libc_start_main@@GLIBC_2.2.5")' > a.script
$ g++ a.script
/usr/lib/gcc/x86_64-redhat-linux/4.8.5/../../../../lib64/crt1.o: In function `_start':
(.text+0x20): undefined reference to `main'
collect2: error: ld returned 1 exit status
but rejects them if unquoted:
$ echo 'EXTERN(__libc_start_main@@GLIBC_2.2.5)' > a.script
$ g++ a.script
a.script: file not recognized: File format not recognized
collect2: error: ld returned 1 exit status
To maintain compatibility with existing linker scripts support quoted
strings in lld as well.
Patch by Lucian Adrian Grijincu.
Differential Revision: https://reviews.llvm.org/D57987
llvm-svn: 353756
Summary:
The message "could not get the buffer for the member defining symbol"
now also contains the name of the archive and the name of the archive
member that we tried to open.
Reviewers: ruiu
Subscribers: llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D57974
llvm-svn: 353572
The code producing error messages relating to missing thin archive
members was missing any testing as far as I could see, so this patch
adds a test for it.
Reviewed by: ruiu
Differential Revision: https://reviews.llvm.org/D57899
llvm-svn: 353508
Add a flag to allow symbols to have a wasm import name which differs from the
linker symbol name, allowing the linker to link code using the import_module
attribute.
Differential Revision: https://reviews.llvm.org/D57632
llvm-svn: 353473
R_X86_64_PC{8,16} relocations are sign-extended, so when we check
for relocation overflow, we had to use checkInt instead of checkUInt.
I confirmed that GNU linkers create the same output for the test case.
llvm-svn: 353437
This is the same as D57749, but for x64 target.
"ELF Handling For Thread-Local Storage" p41 says (https://www.akkadia.org/drepper/tls.pdf):
R_X86_64_GOTTPOFF relocation is used for IE TLS models.
Hence if linker sees this relocation we should add DF_STATIC_TLS flag.
Differential revision: https://reviews.llvm.org/D57821
llvm-svn: 353378
With the following changes:
1) Compilation fix:
std::atomic<bool> HasStaticTlsModel = false; ->
std::atomic<bool> HasStaticTlsModel{false};
2) Adjusted the comment in code.
Initial commit message:
DF_STATIC_TLS flag indicates that the shared object or executable
contains code using a static thread-local storage scheme.
Patch checks if IE/LE relocations were used to check if the code uses
a static model. If so it sets the DF_STATIC_TLS flag.
Differential revision: https://reviews.llvm.org/D57749
----
Modified : /lld/trunk/ELF/Arch/X86.cpp
Modified : /lld/trunk/ELF/Config.h
Modified : /lld/trunk/ELF/SyntheticSections.cpp
Added : /lld/trunk/test/ELF/Inputs/i386-static-tls-model1.s
Added : /lld/trunk/test/ELF/Inputs/i386-static-tls-model2.s
Added : /lld/trunk/test/ELF/Inputs/i386-static-tls-model3.s
Added : /lld/trunk/test/ELF/Inputs/i386-static-tls-model4.s
Added : /lld/trunk/test/ELF/i386-static-tls-model.s
Modified : /lld/trunk/test/ELF/i386-tls-ie-shared.s
Modified : /lld/trunk/test/ELF/tls-dynamic-i686.s
Modified : /lld/trunk/test/ELF/tls-opt-iele-i686-nopic.s
llvm-svn: 353299
DF_STATIC_TLS flag indicates that the shared object or executable
contains code using a static thread-local storage scheme.
Patch checks if IE/LE relocations were used to check if the code uses
a static model. If so it sets the DF_STATIC_TLS flag.
Differential revision: https://reviews.llvm.org/D57749
llvm-svn: 353293
When a thunk is created to a PLT entry, the call to the thunk is converted
to a non-plt expression with fromPlt(). If the thunk becomes unusable we
retarget the relocation back to its original target and try again. When we
do this we need to make sure that we restore the PLT form of the expression
with toPlt().
This change adds a test case that will fail if toPlt() is removed. We need
to have a call to a preemptible symbol defined within the link unit. If
toPlt() is removed then the relocation to the thunk to the PLT entry for the
preemptible symbol will be retargeted to the preemptible symbol itself
instead of its PLT entry.
Differential Revision: https://reviews.llvm.org/D57743
llvm-svn: 353285
Summary:
R_PPC64_TLSGD and R_PPC64_TLSLD are used as markers on TLS code sequences. After GD-to-IE or GD-to-LE relaxation, the next relocation R_PPC64_REL24 should be skipped to not create a false dependency on __tls_get_addr. When linking statically, the false dependency may cause an "undefined symbol: __tls_get_addr" error.
R_PPC64_GOT_TLSGD16_HA
R_PPC64_GOT_TLSGD16_LO
R_PPC64_TLSGD R_TLSDESC_CALL
R_PPC64_REL24 __tls_get_addr
Reviewers: ruiu, sfertile, syzaara, espindola
Reviewed By: sfertile
Subscribers: emaste, nemanjai, arichardson, kbarton, jsji, llvm-commits, tamur
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D57673
llvm-svn: 353262
In a previous patch, I made changes so that PDBs which were
generated on non-Windows platforms contained sensical paths
for the host. While this is an esoteric use case, we need
it to be supported for certain cross compilation scenarios
especially with LLDB, which can debug things on non-Windows
platforms.
However, this regressed a case where you specify /PDBSOURCEPATH
and use a windows-style path. Previously, we would still remove
dots and canonicalize slashes to backslashes, but since my
change intentionally tried to support non-backslash paths, this
was broken.
This patch fixes the situation by trying to guess which path
style the user is specifying when /PDBSOURCEPATH is passed.
It is intentionally conservative, erring on the side of a
Windows path style unless absolutely certain. All dots are
removed and slashes canonicalized to whatever the deduced
path style is after appending the file path to the /PDBSOURCEPATH
argument.
Differential Revision: https://reviews.llvm.org/D57769
llvm-svn: 353250
Summary:
The following patch adds the "None" line to the section to segment mapping dump.
That line lists the sections that do not belong to any segment.
I realize that this change differs from GNU readelf which does not display the latter information.
I'd rather not add this "feature" under a command line option. I think that might introduce confusion, since users would have to
make an additional decision as to if they want to see all of the section-to-segment map or just a subset of it.
Another option is to only print the "None" line if the `--section-mapping` option is passed; however,
that might also introduce some confusion, because the section-to-segment map would be different between`--program-headers`
and the `--section-mapping` output. While the difference is just the "None" line, it seems that if we choose to display
the segment-to-section mapping, then we should always display the whole map including the sections
that do not belong to segments.
```
Section to Segment mapping:
Segment Sections...
00
01 .interp
02 .interp .note.ABI-tag .gnu.hash
03 .init_array .fini_array .dynamic
04 .dynamic
05 .note.ABI-tag
06 .eh_frame_hdr
07
08 .init_array .fini_array .dynamic .got
None .comment .symtab .strtab .shstrtab <--- THIS LINE
```
Reviewers: grimar, rupprecht, jhenderson, espindola
Reviewed By: rupprecht
Subscribers: khemant, emaste, arichardson, llvm-commits
Differential Revision: https://reviews.llvm.org/D57700
llvm-svn: 353217
For MinGW, unique partial sections are much more common, e.g.
comdat functions get sections named e.g. text$symbol.
A moderate sized example of this contains over 200K Chunks
which create 174K unique PartialSections. Prior to SVN r352928
(D57574), linking this took around 1,5 seconds for me, while
it afterwards takes around 13 minutes. After this patch, the
linking time is back to what it was before.
The std::find_if in findPartialSection will do a linear scan of
the whole container until a match is found. To use something like
binary_search or the std::set container's own methods, we'd need
to already have a PartialSection*.
Reinstate a proper map instead of having a set with a custom sorting
comparator.
Differential Revision: https://reviews.llvm.org/D57666
llvm-svn: 353146
Summary:
This patch fixes clang-tidy warnings on wasm-only files.
The list of checks used is:
`-*,clang-diagnostic-*,llvm-*,misc-*,-misc-unused-parameters,readability-identifier-naming,modernize-*`
(LLVM's default .clang-tidy list is the same except it does not have
`modernize-*`.)
The list of fixes are:
- Variable names start with an uppercase letter
- Function names start with a lowercase letter
- Use `auto` when you use casts so the type is evident
Reviewers: sbc100
Subscribers: dschuff, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D57499
llvm-svn: 353076
Summary:
This follows the ld.bfd/gold behavior.
The error check is useful as it captures a common type of ld.so undefined symbol errors as link-time errors:
// a.cc => a.so (not linked with -z defs)
void f(); // f is undefined
void g() { f(); }
// b.cc => executable with a DT_NEEDED entry on a.so
void g();
int main() { g(); }
// ld.so errors when g() is executed (lazy binding) or when the program is started (-z now)
// symbol lookup error: ... undefined symbol: f
Reviewers: ruiu, grimar, pcc, espindola
Reviewed By: ruiu
Subscribers: llvm-commits, emaste, arichardson
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D57569
llvm-svn: 352943
On ARM64, this is normally necessary only after a module exceeds
128 MB in size (while the limit for thumb is 16 MB). For conditional
branches, the range limit is only 1 MB though (the same as for thumb),
and for the tbz instruction, the range is only 32 KB, which allows for
a test much smaller than the full 128 MB.
This fixes PR40467.
Differential Revision: https://reviews.llvm.org/D57575
llvm-svn: 352929
When writing a PDB, the OutputSection of all chunks need to be set.
The thunks are added directly to OutputSection after the normal
machinery that sets it for all other chunks.
This fixes part of PR40467.
Differential Revision: https://reviews.llvm.org/D57574
llvm-svn: 352928
Fangrui Song