Commit Graph

13541 Commits

Author SHA1 Message Date
Sam Clegg a38ed62ea8 [lld][WebAssembly] Feedback from D92038. NFC
Differential Revision: https://reviews.llvm.org/D92429
2020-12-01 14:53:59 -08:00
Jez Ng 6b3eecd22a [lld-macho] Extend PIE option handling
* Enable PIE by default if targeting 10.6 or above on x86-64. (The
  manpage says 10.7, but that actually applies only to i386, and in
  general varies based on the target platform. I didn't update the
  manpage because listing all the different behaviors would make for a
  pretty long description.)
* Add support for `-no_pie`
* Remove `HelpHidden` from `-pie`

Reviewed By: thakis

Differential Revision: https://reviews.llvm.org/D92362
2020-12-01 14:35:51 -08:00
David Blaikie 615f63e149 Revert "[FastISel] Flush local value map on ever instruction" and dependent patches
This reverts commit cf1c774d6a.

This change caused several regressions in the gdb test suite - at least
a sample of which was due to line zero instructions making breakpoints
un-lined. I think they're worth investigating/understanding more (&
possibly addressing) before moving forward with this change.

Revert "[FastISel] NFC: Clean up unnecessary bookkeeping"
This reverts commit 3fd39d3694.

Revert "[FastISel] NFC: Remove obsolete -fast-isel-sink-local-values option"
This reverts commit a474657e30.

Revert "Remove static function unused after cf1c774."
This reverts commit dc35368ccf.

Revert "[lldb] Fix TestThreadStepOut.py after "Flush local value map on every instruction""
This reverts commit 53a14a47ee.
2020-12-01 14:26:23 -08:00
Arthur Eubanks 99d82412f8 [LLD][ELF][NewPM] Add option to force legacy PM
In preparation for the NPM switch.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D92417
2020-12-01 13:41:17 -08:00
Arthur Eubanks 1314a4938f [LTO][wasm][NewPM] Allow using new pass manager for wasm LTO
Reviewed By: sbc100

Differential Revision: https://reviews.llvm.org/D92150
2020-12-01 12:22:40 -08:00
Fangrui Song bb993b1d9d [ELF][test] Fix lto/version-script2.ll 2020-12-01 10:22:33 -08:00
Arthur Eubanks 26d3aaeb3a [LTO][NewPM] Run verifier when doing LTO
This matches the legacy PM.

Reviewed By: ychen

Differential Revision: https://reviews.llvm.org/D92138
2020-12-01 10:14:53 -08:00
Fangrui Song 843c2b2303 [ELF] Error for undefined foo@v1
If an object file has an undefined foo@v1, we emit a dynamic symbol foo.
This is incorrect if at runtime a shared object provides the non-default version foo@v1
(the undefined foo may bind to foo@@v2, for example).

GNU ld issues an error for this case, even if foo@v1 is undefined weak
(https://sourceware.org/bugzilla/show_bug.cgi?id=3351). This behavior makes
sense because to represent an undefined foo@v1, we have to construct a Verneed
entry. However, without knowing the defining filename, we cannot construct a
Verneed entry (Verneed::vn_file is unavailable).

This patch implements the error.

Depends on D92258

Reviewed By: grimar

Differential Revision: https://reviews.llvm.org/D92260
2020-12-01 08:59:54 -08:00
Fangrui Song 941e9336d0 [ELF] Make foo@@v1 resolve undefined foo@v1
The symbol resolution rules for versioned symbols are:

* foo@@v1 (default version) resolves both undefined foo and foo@v1
* foo@v1 (non-default version) resolves undefined foo@v1

Note, foo@@v1 must be defined (the assembler errors if attempting to
create an undefined foo@@v1).

For defined foo@@v1 in a shared object, we call `SymbolTable::addSymbol` twice,
one for foo and the other for foo@v1. We don't do the same for object files, so
foo@@v1 defined in one object file incorrectly does not resolve a foo@v1
reference in another object file.

This patch fixes the issue by reusing the --wrap code to redirect symbols in
object files. This has to be done after processing input files because
foo and foo@v1 are two separate symbols if we haven't seen foo@@v1.

Add a helper `Symbol::getVersionSuffix` to retrieve the optional trailing
`@...` or `@@...` from the possibly truncated symbol name.

Depends on D92258

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D92259
2020-12-01 08:54:01 -08:00
Fangrui Song a5f95887d0 [ELF][test] Add some tests for versioned symbols in object files
Test the symbol resolution related to

* defined foo@@v1 and foo@v1 in object files/shared objects
* undefined foo@v1
* weak foo@@v1 and foo@v1
* visibility
* interaction with --wrap.

Reviewed By: grimar

Differential Revision: https://reviews.llvm.org/D92258
2020-12-01 08:49:14 -08:00
Nico Weber 4431c212a0 lld/ELF: Make three rarely-used flags work with --reproduce
All three use readFile() for their argument so their argument file is
already copied to the tar, but we weren't rewriting the argument to
point to the path used in the tar file.

No test because the change is trivial (several other flags in
createResponseFile() also aren't tested, likely for the same reason.)

Differential Revision: https://reviews.llvm.org/D92356
2020-12-01 09:20:29 -05:00
Wei Wang 3acda91742 [Remarks][1/2] Expand remarks hotness threshold option support in more tools
This is the #1 of 2 changes that make remarks hotness threshold option
available in more tools. The changes also allow the threshold to sync with
hotness threshold from profile summary with special value 'auto'.

This change modifies the interface of lto::setupLLVMOptimizationRemarks() to
accept remarks hotness threshold. Update all the tools that use it with remarks
hotness threshold options:

* lld: '--opt-remarks-hotness-threshold='
* llvm-lto2: '--pass-remarks-hotness-threshold='
* llvm-lto: '--lto-pass-remarks-hotness-threshold='
* gold plugin: '-plugin-opt=opt-remarks-hotness-threshold='

Differential Revision: https://reviews.llvm.org/D85809
2020-11-30 21:55:49 -08:00
Amy Huang efd1ec0dec Recommit "[llvm-symbolizer] Switch to using native symbolizer by default on Windows"
This reverts commit 1b63177a56.
2020-11-30 17:36:12 -08:00
Amy Huang 8cdf4920c4 [llvm-symbolizer] Fix typo in llvm-symbolizer test from a previous commit.
(Commit was 00bbef2bb2)
2020-11-30 15:08:11 -08:00
Amy Huang 00bbef2bb2 [llvm-symbolizer] Fix native symbolization on windows for inline sites.
The existing code handles this correctly and I checked that the code
in NativeInlineSiteSymbol also handles this correctly, but it was
wrong in the NativeFunctionSymbol code.

Differential Revision: https://reviews.llvm.org/D92134
2020-11-30 14:27:35 -08:00
Nico Weber 78c04fe99e [lld/mac] Don't warn on -bundle and -execute flags
They've been implemented since D87856 but since they still were
HelpHidden, the driver still warned claiming they were implemented.
Remove HelpHidden.

Use -fatal_warnings to test that the flags now don't warn. The
test depends on D91894 and D91891 to pass.

Differential Revision: https://reviews.llvm.org/D91971
2020-11-30 16:07:58 -05:00
Nico Weber ebac710009 [lld-macho] Don't warn on non-existent system libraries
Now, new mach-o lld no longer warns if the isysroot has just
usr/lib and System/Library/Frameworks but is missing usr/local/lib
and System/Frameworks.

This matches ld64 and old mach-o lld and fixes a regression from D85992.

It also fixes the only test failure in `check-lld` when running it
on an M1 Mac.

Differential Revision: https://reviews.llvm.org/D91891
2020-11-30 16:07:20 -05:00
Fangrui Song 589e10f858 [ELF] Don't relax R_X86_64_GOTPCRELX if addend != -4
clang may produce `movl x@GOTPCREL+4(%rip), %eax` when loading the high 32 bits
of the address of a global variable in -fpic/-fpie mode.

If assembled by GNU as, the fixup emits an R_X86_64_GOTPCRELX with an
addend != -4. The instruction loads from the GOT entry with an offset
and thus it is incorrect to relax the instruction.

If assembled by the integrated assembler, we emit R_X86_64_GOTPCREL for
relocations that definitely cannot be relaxed (D92114), so this patch is not
needed.

This patch disables the relaxation, which is compatible with the implementation in GNU ld
("Add R_X86_64_[REX_]GOTPCRELX support to gas and ld").

Reviewed By: grimar, jhenderson

Differential Revision: https://reviews.llvm.org/D91993
2020-11-30 08:30:19 -08:00
Nico Weber c0e4020c92 [lld-macho] Implement -fatal_warnings
Differential Revision: https://reviews.llvm.org/D91894
2020-11-30 09:29:21 -05:00
Nico Weber 83e60f5a55 [lld/mac] Add --reproduce option
This adds support for ld.lld's --reproduce / lld-link's /reproduce:
flag to the MachO port. This flag can be added to a link command
to make the link write a tar file containing all inputs to the link
and a response file containing the link command. This can be used
to reproduce the link on another machine, which is useful for sharing
bug report inputs or performance test loads.

Since the linker is usually called through the clang driver and
adding linker flags can be a bit cumbersome, setting the env var
`LLD_REPRODUCE=foo.tar` triggers the feature as well.

The file response.txt in the archive can be used with
`ld64.lld.darwinnew $(cat response.txt)` as long as the contents are
smaller than the command-line limit, or with `ld64.lld.darwinnew
@response.txt` once D92149 is in.

The support in this patch is sufficient to create a tar file for
Chromium's base_unittests that can link after unpacking on a different
machine.

Differential Revision: https://reviews.llvm.org/D92274
2020-11-30 08:40:21 -05:00
Nico Weber d20abb1ec3 [mac/lld] Add support for response files
ld64 learned about them in Xcode 12, so we should too.

Differential Revision: https://reviews.llvm.org/D92149
2020-11-30 08:23:58 -05:00
Fangrui Song dfcf1acf13 [ELF] Improve 2 SmallVector<*, N> usage
For --gc-sections, SmallVector<InputSection *, 256> -> SmallVector<InputSection *, 0> because the code bloat (1296 bytes) is not worthwhile (the saved reallocation is negligible).
For OutputSection::compressedData, N=1 is useless (for a compressed .debug_*, the size is always larger than 1).
2020-11-29 14:01:32 -08:00
Fangrui Song 048b16f7fb [ELF] Check --orphan-handling=place (default value) early
The function took 1% (161MiB clang) to 1.7% (an 4.9GiB executable) time.
2020-11-29 12:36:27 -08:00
Nico Weber a0994cbe27 lld-link: Let LLD_REPRODUCE control /reproduce:, like in ld.lld
Also sync help texts for the option between elf and coff ports.

Decisions:
- Do this even if /lldignoreenv is passed. /reproduce: does not affect
  the main output, and this makes the env var more convenient to use.
  (On the other hand, it's now possible to set this env var and forget
  about it, and all future builds in the same shell will be much slower.
  That's true for ld.lld, but posix shells have an easy way to set an
  env var for a single command; in cmd.exe this is not possible without
  contortions. Then again, lld-link runs in posix shells too.)

Original patch rebased across D68378 and D68381.

Differential Revision: https://reviews.llvm.org/D67707
2020-11-27 13:33:55 -05:00
Sam Clegg 48ddf5e182 [lld][WebAssembly] Ensure stub symbols always get address 0
Without this extra flag we can't distingish between stub functions and
functions that happen to have address 0 (relative to __table_base).

Adding this flag bit the base symbol class actually avoids growing the
SymbolUnion struct which would not be true if we added it to the
FunctionSymbol subclass (due to bitbacking).

The previous approach of setting it's table index to zero worked for
normal static relocations but not for `-fPIC` code.

See https://github.com/emscripten-core/emscripten/issues/12819

Differential Revision: https://reviews.llvm.org/D92038
2020-11-25 18:26:34 -08:00
Nico Weber da0aaedcd0 [gn build] (manually) port b534beabee 2020-11-25 20:19:46 -05:00
Amy Huang 1363dfaf31 [CodeView] Avoid emitting empty debug globals subsection.
In https://reviews.llvm.org/D89072 I added static const data members
to the debug subsection for globals. It skipped emitting an S_CONSTANT if it
didn't have a value, which meant the subsection could be empty.

This patch fixes the empty subsection issue.

Differential Revision: https://reviews.llvm.org/D92049
2020-11-25 16:13:32 -08:00
Paul Robinson cf1c774d6a [FastISel] Flush local value map on ever instruction
Local values are constants or addresses that can't be folded into
the instruction that uses them. FastISel materializes these in a
"local value" area that always dominates the current insertion
point, to try to avoid materializing these values more than once
(per block).

https://reviews.llvm.org/D43093 added code to sink these local
value instructions to their first use, which has two beneficial
effects. One, it is likely to avoid some unnecessary spills and
reloads; two, it allows us to attach the debug location of the
user to the local value instruction. The latter effect can
improve the debugging experience for debuggers with a "set next
statement" feature, such as the Visual Studio debugger and PS4
debugger, because instructions to set up constants for a given
statement will be associated with the appropriate source line.

There are also some constants (primarily addresses) that could be
produced by no-op casts or GEP instructions; the main difference
from "local value" instructions is that these are values from
separate IR instructions, and therefore could have multiple users
across multiple basic blocks. D43093 avoided sinking these, even
though they were emitted to the same "local value" area as the
other instructions. The patch comment for D43093 states:

  Local values may also be used by no-op casts, which adds the
  register to the RegFixups table. Without reversing the RegFixups
  map direction, we don't have enough information to sink these
  instructions.

This patch undoes most of D43093, and instead flushes the local
value map after(*) every IR instruction, using that instruction's
debug location. This avoids sometimes incorrect locations used
previously, and emits instructions in a more natural order.

This does mean materialized values are not re-used across IR
instruction boundaries; however, only about 5% of those values
were reused in an experimental self-build of clang.

(*) Actually, just prior to the next instruction. It seems like
it would be cleaner the other way, but I was having trouble
getting that to work.

Differential Revision: https://reviews.llvm.org/D91734
2020-11-25 13:05:00 -05:00
Fangrui Song 50564ca075 [ELF] Rename adjustRelaxExpr to adjustTlsExpr and delete the unused `data` parameter. NFC
Reviewed By: psmith

Differential Revision: https://reviews.llvm.org/D91995
2020-11-25 09:00:55 -08:00
Fangrui Song 572d18397c [ELF] Add TargetInfo::adjustGotPcExpr for `R_GOT_PC` relaxations. NFC
With this change, `TargetInfo::adjustRelaxExpr` is only related to TLS
relaxations and a subsequent clean-up can delete the `data` parameter.

Differential Revision: https://reviews.llvm.org/D92079
2020-11-25 08:43:26 -08:00
Andy Wingo 1933c9d41a [WebAssembly] Factor out WasmTableType in binary format
This commit factors out a WasmTableType definition from WasmTable, as is
the case for WasmGlobal and other data types.  Also add support for
extracting the SymbolName for a table from the linking section's symbol
table.

Differential Revision: https://reviews.llvm.org/D91849
2020-11-25 08:00:08 -08:00
Teresa Johnson 07f234be1c [lld] Add --no-lto-whole-program-visibility
Enables overriding earlier --lto-whole-program-visibility.

Variant of D91583 while discussing alternate ways to identify and
handle the --export-dynamic case.

Differential Revision: https://reviews.llvm.org/D92060
2020-11-24 16:46:08 -08:00
Nico Weber 11b7625833 [lld/mac] Implement basic typo correction for flags
Also use "unknown flag 'flag'" instead of "unknown flag: flag" for
consistency with the other ports.

Differential Revision: https://reviews.llvm.org/D91970
2020-11-24 11:33:39 -05:00
Nico Weber c8414fa941 lld: Fix darwinnew symlink name added in e16c0a9a68 2020-11-24 11:06:51 -05:00
Nico Weber e16c0a9a68 clang+lld: Improve clang+ld.darwinnew.lld interaction, pass -demangle
This patch:
- adds an ld64.lld.darwinnew symlink for lld, to go with f2710d4b57,
  so that `clang -fuse-ld=lld.darwinnew` can be used to test new
  Mach-O lld while it's in bring-up. (The expectation is that we'll
  remove this again once new Mach-O lld is the defauld and only Mach-O
  lld.)
- lets the clang driver know if the linker is lld (currently
  only triggered if `-fuse-ld=lld` or `-fuse-ld=lld.darwinnew` is
  passed). Currently only used for the next point, but could be used
  to implement other features that need close coordination between
  compiler and linker, e.g. having a diag for calling `clang++` instead
  of `clang` when link errors are caused by a missing C++ stdlib.
- lets the clang driver pass `-demangle` to Mach-O lld (both old and
  new), in addition to ld64
- implements -demangle for new Mach-O lld
- changes demangleItanium() to accept _Z, __Z, ___Z, ____Z prefixes
  (and updates one test added in D68014). Mach-O has an extra
  underscore for symbols, and the three (or, on Mach-O, four)
  underscores are used for block names.

Differential Revision: https://reviews.llvm.org/D91884
2020-11-24 08:51:58 -05:00
Martin Storsjö 0b2d84fba8 [LLD] [COFF] Allow wrapping dllimported functions
GNU ld doesn't seem to do this though, but it looks like a reasonable
use case, is easy to implement, and was requested in
https://bugs.llvm.org/show_bug.cgi?id=47384.

Differential Revision: https://reviews.llvm.org/D91689
2020-11-24 10:15:20 +02:00
Amy Huang 1b63177a56 Revert "[llvm-symbolizer] Switch to using native symbolizer by default on Windows"
Breaks some asan tests on the buildbot.

This reverts commit c74b427cb2.
2020-11-23 16:29:45 -08:00
Amy Huang c74b427cb2 [llvm-symbolizer] Switch to using native symbolizer by default on Windows
llvm-symbolizer used to use the DIA SDK for symbolization on
Windows; this patch switches to using native symbolization, which was
implemented recently.

Users can still make the symbolizer use DIA by adding the `-dia` flag
in the LLVM_SYMBOLIZER_OPTS environment variable.

Differential Revision: https://reviews.llvm.org/D91814
2020-11-23 15:57:08 -08:00
Georgii Rymar 9a99d23a1b [lib/Object] - Generalize the RelocationResolver API.
This allows to reuse the RelocationResolver from the code
that doesn't want to deal with `RelocationRef` class.

I am going to use it in llvm-readobj. See the description
of D91530 for more details.

Differential revision: https://reviews.llvm.org/D91533
2020-11-20 10:32:49 +03:00
Sam Clegg f7f0fe6184 [lld][WebAssembly] Convert more tests to asm format. NFC.
Differential Revision: https://reviews.llvm.org/D91681
2020-11-19 16:57:00 -08:00
Gabriel Hjort Åkerlund 2d1f471e45 [Mach0] Fix unused-variable warnings
Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D91519
2020-11-19 10:51:15 +01:00
Sam Clegg 1827005cfc [WebAssembly] Add support for named globals in the object format.
Differential Revision: https://reviews.llvm.org/D91769
2020-11-19 00:17:22 -08:00
Nico Weber c519bc7e16 lld/MachO: Move MachOOptTable to DriverUtils.cpp, remove DriverUtils.h
This makes lld/MachO look more like lld/COFF and lld/ELF, as discussed
in D91640.
2020-11-18 12:33:15 -05:00
Nico Weber 27e73816d6 lld: Make tests depend on llvm-symbolizer after bc98034040
Fixes test failures when building just `check-lld` in a clean build dir.
2020-11-18 11:43:44 -05:00
Georgii Rymar 9aa7898200 Reland "[lib/Support/YAMLTraits] - Don't print leading zeroes when dumping Hex8/Hex16/Hex32 types." (https://reviews.llvm.org/D90930).
This reverts reverting commit fc40a03323
and fixes LLD (MachO/wasm) tests that failed previously.
2020-11-18 13:08:46 +03:00
Andrew Paverd 0139c8af8d [CFGuard] Add address-taken IAT tables and delay-load support
This patch adds support for creating Guard Address-Taken IAT Entry Tables (.giats$y sections) in object files, matching the behavior of MSVC. These contain lists of address-taken imported functions, which are used by the linker to create the final GIATS table.
Additionally, if any DLLs are delay-loaded, the linker must look through the .giats tables and add the respective load thunks of address-taken imports to the GFIDS table, as these are also valid call targets.

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D87544
2020-11-17 18:24:45 -08:00
Sam Clegg 206884bf90 [lld][WebAssembly] Implement --unresolved-symbols
This is a more full featured version of ``--allow-undefined``.
The semantics of the different methods are as follows:

report-all:

   Report all unresolved symbols.  This is the default.  Normally the
   linker will generate an error message for each reported unresolved
   symbol but the option ``--warn-unresolved-symbols`` can change this
   to a warning.

ignore-all:

   Resolve all undefined symbols to zero.  For data and function
   addresses this is trivial.  For direct function calls, the linker
   will generate a trapping stub function in place of the undefined
   function.

import-functions:

   Generate WebAssembly imports for any undefined functions.  Undefined
   data symbols are resolved to zero as in `ignore-all`.  This
   corresponds to the legacy ``--allow-undefined`` flag.

The plan is to followup with a new mode called `import-dynamic` which
allows for statically linked binaries to refer to both data and
functions symbols from the embedder.

Differential Revision: https://reviews.llvm.org/D79248
2020-11-17 16:27:06 -08:00
Amy Huang bc98034040 [llvm-symbolizer] Add inline stack traces for Windows.
This adds inline stack frames for symbolizing on Windows.

Differential Revision: https://reviews.llvm.org/D88988
2020-11-17 13:19:13 -08:00
Fangrui Song 55d310adc0 [ELF] Fix interaction between --unresolved-symbols= and --[no-]allow-shlib-undefined
As mentioned in https://reviews.llvm.org/D67479#1667256 ,

* `--[no-]allow-shlib-undefined` control the diagnostic for an unresolved symbol in a shared object
* `-z defs/-z undefs` control the diagnostic for an unresolved symbol in a regular object file
* `--unresolved-symbols=` controls both bits.

In addition, make --warn-unresolved-symbols affect --no-allow-shlib-undefined.

This patch makes the behavior match GNU ld.

Reviewed By: psmith

Differential Revision: https://reviews.llvm.org/D91510
2020-11-17 12:20:57 -08:00
Nico Weber baa2aa28f5 lld: Add --color-diagnostic to MachO port, harmonize others
This adds `--[no-]color-diagnostics[=auto,never,always]` to
the MachO port and harmonizes the flag in the other ports:
- Consistently use MetaVarName
- Consistently document the non-eq version as alias of the eq version
- Use B<> in the ports that have it (no-op, shorter)
- Fix oversight in COFF port that made the --no flag have the wrong
  prefix

Differential Revision: https://reviews.llvm.org/D91640
2020-11-17 12:58:30 -05:00