Commit Graph

11821 Commits

Author SHA1 Message Date
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
Ali Tamur
5aa7478a55 [lld] Prevent duplicate files in debug line header in dwarf 5.
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
2019-03-25 20:18:27 +00:00
Thomas Lively
84c8652fc3 Revert "[WebAssembly] Add linker options to control feature checking"
This reverts commit 5991328c96.

llvm-svn: 356932
2019-03-25 18:10:26 +00:00
Alexandre Ganea
74d5b33222 [LLD][COFF] Separate module descriptors creation from type/symbol merging
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
2019-03-22 22:07:27 +00:00
Rui Ueyama
d2e0ed7755 Simplify PltSection.
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
2019-03-22 21:17:25 +00:00
Thomas Lively
5991328c96 [WebAssembly] Add linker options to control feature checking
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
2019-03-22 20:43:06 +00:00
Fangrui Song
dc6c0cf94d [DWARF] Refactor RelocVisitor and fix computation of SHT_RELA-typed relocation entries
Summary: This is the lld-side change of D57939

Reviewers: echristo, dblaikie, ruiu, espindola

Reviewed By: echristo, ruiu

Subscribers: jdoerfert, emaste, arichardson, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D57940

llvm-svn: 356730
2019-03-22 02:43:17 +00:00
Reid Kleckner
05ea3a6be3 Fix lld wasm tests after r356610
Apparently stdout is not opened in binary mode, so the executable gets
corrupted when piping to obj2yaml.

llvm-svn: 356694
2019-03-21 18:24:05 +00:00
Peter Smith
54dab70bb7 [ELF][ARM] Revert Redesign of .ARM.exidx handling to use a SyntheticSection
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
2019-03-21 17:17:54 +00:00
Peter Smith
d3511a214e [ELF][ARM] Redesign of .ARM.exidx handling to use a SyntheticSection
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
2019-03-21 14:06:40 +00:00
Thomas Lively
f6f4f84378 [WebAssembly] Target features section
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
2019-03-20 20:26:45 +00:00
Robert Lougher
364cb6b5d7 [TailCallElim] Update tests for LTO pipeline change
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
2019-03-20 19:05:05 +00:00
Serge Guelton
a1aa7a4054 Python 2/3 compatibility
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
2019-03-20 07:42:13 +00:00
Fangrui Song
1092fc9057 [ELF] Allow sh_entsize to be unrelated to sh_addralign and not a power of 2
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
2019-03-18 23:49:18 +00:00
Alexandre Ganea
4aeea4cc42 [DebugInfo][PDB] Don't write empty debug streams
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
2019-03-18 19:13:23 +00:00
Nico Weber
2b1dca79f2 lld-link: Run conflict-mangled.test on all systems
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
2019-03-18 16:51:23 +00:00
Siva Chandra
1915e2be93 [ELF] Emit weak-undef symbols in .dynsym of a PIE binary only if linked against shared libs.
Reviewers: espindola

Subscribers: emaste, arichardson, MaskRay, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D59275

llvm-svn: 356374
2019-03-18 15:32:57 +00:00
George Rimar
738146ab33 [LLD][ELF] - Replace one of the tests with a YAML version.
This removes one more binary from the inputs.

Differential revision: https://reviews.llvm.org/D59085

llvm-svn: 356334
2019-03-17 15:46:03 +00:00
Fangrui Song
6778b53e95 [ELF] De-virtualize findOrphanPos, excludeLibs and handleARMTlsRelocation
llvm-svn: 356331
2019-03-17 13:53:42 +00:00
Sam Clegg
632c217921 [WebAssembly] Error on R_WASM_MEMORY_ADDR relocations against undefined data symbols.
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
2019-03-16 01:18:12 +00:00
Fangrui Song
4ac6d7e4b8 [COFF] Delete unused declarations and add a missing forward declaration. NFC
llvm-svn: 356241
2019-03-15 09:40:03 +00:00
Fangrui Song
f9695e166b [ELF] Delete unused forward declarations and unused DynamicReloc::getInputSec(). NFC
llvm-svn: 356239
2019-03-15 07:16:39 +00:00
Fangrui Song
76a7ecb3ae [ELF] De-template wrapSymbols, isReserved and addGotEntry. NFC
llvm-svn: 356237
2019-03-15 06:58:23 +00:00
Fangrui Song
639058d7c9 [ELF] Add a test for large .bss.rel.ro
Reviewers: ruiu, pcc, espindola

Reviewed By: pcc

Subscribers: emaste, arichardson, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D59404

llvm-svn: 356230
2019-03-15 03:37:42 +00:00
Fangrui Song
f4646a0bb1 [ELF] Fix 3 tests after D56828
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
2019-03-15 03:20:13 +00:00
Fangrui Song
e8710ef1fb [ELF] Split RW PT_LOAD on the PT_GNU_RELRO boundary
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
2019-03-15 01:29:57 +00:00