Commit Graph

11846 Commits

Author SHA1 Message Date
Rui Ueyama 4af8d47d05 Fix -emit-reloc against local symbols.
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
2019-04-08 06:45:07 +00:00
Peter Collingbourne 883ab235ee ELF: De-template ELFFileBase. NFCI.
Differential Revision: https://reviews.llvm.org/D60304

llvm-svn: 357806
2019-04-05 20:16:26 +00:00
Peter Collingbourne ad4376e8af ELF: Simplify. NFCI.
Differential Revision: https://reviews.llvm.org/D60299

llvm-svn: 357739
2019-04-05 01:31:40 +00:00
Rui Ueyama 7c28937baf Remove redundant parameters. NFC.
llvm-svn: 357738
2019-04-05 01:30:09 +00:00
Sam Clegg a116d91ba2 [WebAssembly] Include function in wasm table when used in R_WASM_TABLE_INDEX_REL_SLEB
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
2019-04-05 00:35:12 +00:00
Sam Clegg 09137be7f8 [WebAssembly] Apply data relocations at runtime in shared objects
See: https://github.com/WebAssembly/tool-conventions/blob/master/DynamicLinking.md

Data section relocations in wasm shared libraries are applied by the
library itself at static constructor time.  This change adds a new
synthetic function that applies relocations to relevant memory locations
on startup.

Differential Revision: https://reviews.llvm.org/D59278

llvm-svn: 357715
2019-04-04 18:40:51 +00:00
Sam Clegg 2a7cac932b [WebAssembly] Add new explicit relocation types for PIC relocations
See https://github.com/WebAssembly/tool-conventions/pull/106

Differential Revision: https://reviews.llvm.org/D59907

llvm-svn: 357710
2019-04-04 17:43:50 +00:00
Joseph Tremoulet 9f598ac706 [COFF] Fix delay import directory iterator
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
2019-04-04 14:13:28 +00:00
Peter Collingbourne 8238604259 ELF: Move SymtabSHNDX and getSectionIndex() to ObjFile. NFCI.
Differential Revision: https://reviews.llvm.org/D60244

llvm-svn: 357670
2019-04-04 03:13:51 +00:00
Reid Kleckner e10d00419a [codeview] Remove Type member from CVRecord
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
2019-04-04 00:28:48 +00:00
George Rimar ff3397247f [LLD] - Update the test cases after yaml2obj change.
https://reviews.llvm.org/D60122 (r357595) changed the
symbols description format.

This change updates the LLD tests.

llvm-svn: 357596
2019-04-03 14:54:22 +00:00
Reid Kleckner cc525c97b7 [COFF] Reduce the size of Chunk and SectionChunk, NFC
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
2019-04-02 22:11:58 +00:00
Alexandre Ganea 19775a4c67 [LLD][COFF] Move type merging structures out of PDB.cpp. NFC
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
2019-04-02 20:43:19 +00:00
Matthew Voss 3c023420d1 [NFC][LLD] Specify namespaces explicity to fix build failure on GCC 5 after r357383
llvm-svn: 357421
2019-04-01 19:23:56 +00:00
Peter Collingbourne a9e847238e ELF: Perform per-section .ARM.exidx processing during combineEhFrameSections(). NFCI.
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
2019-04-01 18:01:18 +00:00
Alexandre Ganea 30c2f20e55 Fix builder.
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-fuzzer/builds/24702/steps/check-fuzzer/logs/stdio

llvm-svn: 357391
2019-04-01 14:37:36 +00:00
Alexandre Ganea bf55c4e3e3 [LLD][COFF] Early dependency detection
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
2019-04-01 13:36:59 +00:00
Fangrui Song d83fb24533 [ELF] Rename SyntheticSection::empty to more appropriate isNeeded() with opposite meaning
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
2019-04-01 08:16:08 +00:00
Rui Ueyama a77ea59c4d Simplify. NFC.
llvm-svn: 357373
2019-04-01 00:25:17 +00:00
Rui Ueyama 68b9f45fee Replace `typedef A B` with `using B = A`. NFC.
I did this using Perl.

Differential Revision: https://reviews.llvm.org/D60003

llvm-svn: 357372
2019-04-01 00:11:24 +00:00
Sam Clegg e3a845e25e Re-land "[WebAssembly] Improve invalid relocation error message""
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
2019-03-29 22:56:39 +00:00
Alexandre Ganea b13f064b5d Fix build following r357308 : Ensure only live thunks are considered when creating import modules
llvm-svn: 357316
2019-03-29 21:24:19 +00:00
Reid Kleckner ba708619ad Don't copy the .drective section with std::string
Both COFF and bitcode input files expose these as stable strings.

llvm-svn: 357314
2019-03-29 21:00:22 +00:00
Thomas Lively 06391f34bd [WebAssembly] "atomics" feature requires shared memory
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
2019-03-29 20:43:49 +00:00
Alexandre Ganea 09cca5b243 [LLD][COFF] Generate import modules & COFF groups in PDB
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
2019-03-29 20:25:34 +00:00
Alexandre Ganea 347a45ccd5 [LLD][COFF] Improve checkFailIfMismatch()
As suggested by ruiu here (https://reviews.llvm.org/D58910#1425484), defer a call to toString(File) until it's really needed (if there's an error)

Differential Revision: https://reviews.llvm.org/D59411

llvm-svn: 357305
2019-03-29 19:58:58 +00:00
Fangrui Song 8048fe2b8c [ELF][MachO][wasm] Simplify range-style std::find{,_if} with STLExtras.h utilities. NFC
llvm-svn: 357269
2019-03-29 16:21:16 +00:00
Derek Schuff 0c9ea10530 Revert "[WebAssembly] Improve invalid relocation error message"
This reverts commit 0805ec5f7b.

llvm-svn: 357225
2019-03-29 00:05:00 +00:00
Derek Schuff ac727e8647 Revert "[WebAssembly] Improve invalid relocation error message"
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
2019-03-29 00:04:58 +00:00
Rui Ueyama 6528f2eac9 Remove a duplicate assignment. NFC.
llvm-svn: 357223
2019-03-28 23:53:38 +00:00
Rumeet Dhindsa 45bd9b2567 Fixed the lld test using ld-lld command to use ld.lld instead.
Differential Revision: https://reviews.llvm.org/D59962

llvm-svn: 357216
2019-03-28 22:14:46 +00:00
Reid Kleckner 1600490af1 [COFF] Optimize range extension thunk insertion memory usage
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
2019-03-28 18:30:03 +00:00
Rui Ueyama f28825bc06 Create an instance of Target after reading all input files. NFC.
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
2019-03-28 17:38:53 +00:00
Rui Ueyama 8521ba37d7 Make a member function a non-member function.
Since this member function doesn't use anything in the class,
it doesn't have to be a member of the class.

llvm-svn: 357193
2019-03-28 17:35:00 +00:00
Rui Ueyama 676d25ab94 De-template X86_64TargetInfo. NFC.
llvm-svn: 357191
2019-03-28 17:31:12 +00:00
Benjamin Kramer ba2ea93ad1 Make helper functions static. NFC.
llvm-svn: 357187
2019-03-28 17:18:42 +00:00
Rui Ueyama c694633a12 Make TargetInfo const. NFC.
We do not mutate a TargetInfo instance after creating it. This change
makes it explicit.

llvm-svn: 357185
2019-03-28 17:05:09 +00:00
Peter Smith 3ce9af9370 [ELF][ARM] Recommit Redesign of .ARM.exidx handling to use a SyntheticSection
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
2019-03-28 11:10:20 +00:00
Sam Clegg a9958fc30d [WebAssembly] Fix typo from rL357143
llvm-svn: 357144
2019-03-28 02:04:31 +00:00
Sam Clegg 0805ec5f7b [WebAssembly] Improve invalid relocation error message
This message now matches the equivalent message in the ELF linker.

Differential Revision: https://reviews.llvm.org/D59860

llvm-svn: 357143
2019-03-28 02:02:07 +00:00
Rui Ueyama a0a50a7a5b Inline a trivial function. NFC.
I found that hiding this particular actual expression doesn't help
readers understand the code. So I remove and inline that function.

llvm-svn: 357140
2019-03-28 01:37:48 +00:00
Rui Ueyama 432030e843 [ELF] Dump symbols ordered by profiled guided section layout to file.
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
2019-03-27 23:52:22 +00:00
Andrew Ng e6b6ab2c66 [LLD] Restore tests that use "-" as output
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
2019-03-27 15:30:52 +00:00
Ali Tamur cea9548028 Revert "[lld] Reapply "Prevent duplicate files in debug line header in dwarf 5.""
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
2019-03-26 19:57:13 +00:00
Sam Clegg 492f752969 [WebAssembly] Initial implementation of PIC code generation
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
2019-03-26 19:46:15 +00:00
Ali Tamur 5c2f176ccc [lld] Reapply "Prevent duplicate files in debug line header in dwarf 5."
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
2019-03-26 18:59:52 +00:00
Thomas Lively 82de51a3ae Reland "[WebAssembly] Add linker options to control feature checking"
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
2019-03-26 04:11:05 +00:00
Fangrui Song 210949a221 [ELF] Change GOT*_FROM_END (relative to end(.got)) to GOTPLT* (start(.got.plt))
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
2019-03-25 23:46:19 +00:00
Rui Ueyama e6c24299d2 Use a class instead of lambda-based callbacks to organize garbage collector.
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
2019-03-25 23:28:47 +00:00
Ali Tamur 800fe977d0 Revert "[lld] Prevent duplicate files in debug line header in dwarf 5."
This reverts commit 5aa7478a55.

Some things are broken; I will fix and try to commit again.

llvm-svn: 356949
2019-03-25 21:06:02 +00:00