Commit Graph

446 Commits

Author SHA1 Message Date
Rui Ueyama 11ca38f421 COFF: Add support for /force:multiple option
Patch by Thomas Roughton.

This patch adds support for linking with multiple definitions to LLD's
COFF driver, in line with link.exe's /force:multiple option.

Differential Revision: https://reviews.llvm.org/D50598

llvm-svn: 342191
2018-09-13 22:05:10 +00:00
Nico Weber f1828e3240 lld-link: For nonexisting inputs, omit follow-on diagnostics
For lld-link missing.obj, lld-link currently prints:

  lld-link: error: could not open foo.obj: No such file or directory
  lld-link: warning: /machine is not specified. x64 is assumed
  lld-link: error: subsystem must be defined

The 2nd and 3rd diagnostics are consequences of the input not existing and are
not interesting. If input files are missing, the best thing we can do is point
that out and then return.

Differential Revision: https://reviews.llvm.org/D51981

llvm-svn: 342158
2018-09-13 18:13:21 +00:00
Martin Storsjo a47957ab13 [COFF] Allow exporting all symbols from system libraries specfied with -wholearchive:
When building a shared libc++.dll, it pulls in libc++abi.a statically
with the --wholearchive flag. If such a build is done with
--export-all-symbols, it's reasonable to assume that everything
from that library also should be exported with the same rules as normal
local object files, even though we normally avoid autoexporting things
from libc++abi.a in other cases when linking a DLL (user code).

Differential Revision: https://reviews.llvm.org/D51529

llvm-svn: 341403
2018-09-04 20:56:56 +00:00
Martin Storsjo cfbbb707f5 [COFF] Merge the .ctors, .dtors and .CRT sections into .rdata for MinGW
There's no point in keeping them as separate sections.

This differs from GNU ld, which places .ctors and .dtors content in
.text (implemented by a built-in linker script). But since the content
only is pointers, there's no need to have it executable.

GNU ld also leaves .CRT separate as its own standalone section.

MSVC merges .CRT into .rdata similarly, with a directive embedded in
an object file in msvcrt.lib or libcmt.lib.

Differential Revision: https://reviews.llvm.org/D51414

llvm-svn: 340940
2018-08-29 17:24:10 +00:00
Martin Storsjo eac1b05f1d [COFF] Support MinGW automatic dllimport of data
Normally, in order to reference exported data symbols from a different
DLL, the declarations need to have the dllimport attribute, in order to
use the __imp_<var> symbol (which contains an address to the actual
variable) instead of the variable itself directly. This isn't an issue
in the same way for functions, since any reference to the function without
the dllimport attribute will end up as a reference to a thunk which loads
the actual target function from the import address table (IAT).

GNU ld, in MinGW environments, supports automatically importing data
symbols from DLLs, even if the references didn't have the appropriate
dllimport attribute. Since the PE/COFF format doesn't support the kind
of relocations that this would require, the MinGW's CRT startup code
has an custom framework of their own for manually fixing the missing
relocations once module is loaded and the target addresses in the IAT
are known.

For this to work, the linker (originall in GNU ld) creates a list of
remaining references needing fixup, which the runtime processes on
startup before handing over control to user code.

While this feature is rather controversial, it's one of the main features
allowing unix style libraries to be used on windows without any extra
porting effort.

Some sort of automatic fixing of data imports is also necessary for the
itanium C++ ABI on windows (as clang implements it right now) for importing
vtable pointers in certain cases, see D43184 for some discussion on that.

The runtime pseudo relocation handler supports 8/16/32/64 bit addresses,
either PC relative references (like IMAGE_REL_*_REL32*) or absolute
references (IMAGE_REL_AMD64_ADDR32, IMAGE_REL_AMD64_ADDR32,
IMAGE_REL_I386_DIR32). On linking, the relocation is handled as a
relocation against the corresponding IAT slot. For the absolute references,
a normal base relocation is created, to update the embedded address
in case the image is loaded at a different address.

The list of runtime pseudo relocations contains the RVA of the
imported symbol (the IAT slot), the RVA of the location the relocation
should be applied to, and a size of the memory location. When the
relocations are fixed at runtime, the difference between the actual
IAT slot value and the IAT slot address is added to the reference,
doing the right thing for both absolute and relative references.

With this patch alone, things work fine for i386 binaries, and mostly
for x86_64 binaries, with feature parity with GNU ld. Despite this,
there are a few gotchas:
- References to data from within code works fine on both x86 architectures,
  since their relocations consist of plain 32 or 64 bit absolute/relative
  references. On ARM and AArch64, references to data doesn't consist of
  a plain 32 or 64 bit embedded address or offset in the code. On ARMNT,
  it's usually a MOVW+MOVT instruction pair represented by a
  IMAGE_REL_ARM_MOV32T relocation, each instruction containing 16 bit of
  the target address), on AArch64, it's usually an ADRP+ADD/LDR/STR
  instruction pair with an even more complex encoding, storing a PC
  relative address (with a range of +/- 4 GB). This could theoretically
  be remedied by extending the runtime pseudo relocation handler with new
  relocation types, to support these instruction encodings. This isn't an
  issue for GCC/GNU ld since they don't support windows on ARMNT/AArch64.
- For x86_64, if references in code are encoded as 32 bit PC relative
  offsets, the runtime relocation will fail if the target turns out to be
  out of range for a 32 bit offset.
- Fixing up the relocations at runtime requires making sections writable
  if necessary, with the VirtualProtect function. In Windows Store/UWP apps,
  this function is forbidden.

These limitations are addressed by a few later patches in lld and
llvm.

Differential Revision: https://reviews.llvm.org/D50917

llvm-svn: 340726
2018-08-27 08:43:31 +00:00
Rui Ueyama 41831204c7 Rename a function to follow the LLVM coding style.
llvm-svn: 340716
2018-08-27 06:18:10 +00:00
Peter Collingbourne ab038025a5 COFF: Implement safe ICF on rodata using address-significance tables.
Differential Revision: https://reviews.llvm.org/D51050

llvm-svn: 340555
2018-08-23 17:44:42 +00:00
Nico Weber 386bf1216e win: Omit ".exe" from lld warning and error messages.
This is a minor follow-up to https://reviews.llvm.org/D49189. On Windows, lld
used to print "lld-link.exe: error: ...". Now it just prints "lld-link: error:
...". This matches what link.exe does (it prints "LINK : ...") and makes lld's
output less dependent on the host system.

https://reviews.llvm.org/D51133

llvm-svn: 340487
2018-08-22 23:52:13 +00:00
Nico Weber ebc27c4873 lld-link: Emit warning if one each of {main,wmain} and {WinMain,wWinMain} exist and no /subsystem: flag is passed.
Similar to link.exe's LNK4031.
https://reviews.llvm.org/D51076

llvm-svn: 340420
2018-08-22 16:47:16 +00:00
Nico Weber f4f5b7eea3 lld-link: Take /SUBSYSTEM into account for automatic /ENTRY detection.
If /subsystem:windows is passed, link.exe only looks for WinMain and wWinMain,
and if /subsystem:console is passed it only looks for main and wmain. lld-link
used to look for all 4 in both cases. This patch makes lld-link match
link.exe's behavior.

This requires that the subsystem is known by the time findDefaultEntry() gets
called. findDefaultEntry() is called before the main link loop, so that the
loop can mark the entry point as undefined. That means inferSubsystem() has to
be called above the main loop as well. This in turn means /subsystem: from
.drectve sections only has an effect on entry point inference for obj files
passed to lld-link directly (and not in obj files found later in .lib files).
link.exe seems to ignore /subsystem: for obj files from lib files completely
(while in lld it's ignored only for entry point detection but it still
overrides /subsystem: flags passed on the command line for the value that gets
written in the output file).

Also, if the subsytem isn't needed (e.g. when only writing a /def: lib file and
not writing a coff file), link.exe doesn't complain if the subsystem isn't
known, so both subsystem and entry point handling should be below the early
return lld has for that case.

Fixes PR36523.
https://reviews.llvm.org/D50316

llvm-svn: 339165
2018-08-07 19:10:28 +00:00
Martin Storsjo 214d69975c [COFF] Remove a superfluous warning about aligncomm for non-common symbols
It's not an error if a common symbol (uninitialized data, with alignment
specified via the aligncomm directive) is replaced with a regular
one with initialized data (with alignment specified via the section
chunk).

Differential Revision: https://reviews.llvm.org/D50268

llvm-svn: 339049
2018-08-06 19:49:18 +00:00
Nico Weber 397985db51 lld-link: Simplify LinkerDriver::findDefaultEntry()
No intended behavior change. Not repeating the CRTStartup names makes fixing
PR36523 simpler.

https://reviews.llvm.org/D50253

llvm-svn: 338911
2018-08-03 18:32:44 +00:00
Nico Weber d48d5f086f lld-link: Fix subsystem inference for non-console apps on 32-bit, and fix entry point inference on 32-bit with /nodefaultlib
LinkerDriver::inferSubsystem() used to do Symtab->findUnderscore("WinMain"),
but WinMain is stdcall in 32-bit and is hence is called _WinMain@16. Instead,
Symtab->findMangle(mangle("WinMain")) needs to be called.

But since LinkerDriver::inferSubsystem() and LinkerDriver::findDefaultEntry()
both need to call this, introduce a common helper function for this and call it
from both places. (Also call it for "main" for consistency, even though
findUnderscore() is enough for main since that's __cdecl on 32-bit).

This also exposed a bug for /nodefaultlib entrypoint inference: The code here
called findMangle(Sym) instead of findMangle(mangle(Sym)), again doing the
wrong thing on 32-bit. Fix that too.

While here, make Driver::mangle() a static free function.

https://reviews.llvm.org/D50184

llvm-svn: 338877
2018-08-03 12:00:12 +00:00
Nico Weber 11f14904d3 lld-link: Remove /msvclto option
This was useful for LTO bringup in lld-link while lld couldn't write PDBs. Now
that it can, this should no longer be needed. Hopefully the flag is obscure
enough and recent enough, that nobody uses it – but if somebody should use it,
they should be able to just stop passing it and things should continue to work.

https://reviews.llvm.org/D50139

llvm-svn: 338615
2018-08-01 19:00:49 +00:00
Rui Ueyama 279621fbf0 [COFF] clean up global resources after completion
Patch by Andrew Kelley.

Previously, running lld::coff::link() twice in the same process would
access stale pointers because of these global variables not being reset.
After this patch, lld::coff::link() can be called any number of times,
just like its ELF and MACH-O counterparts.

Differential Revision: https://reviews.llvm.org/D49856

llvm-svn: 338042
2018-07-26 17:11:24 +00:00
Nico Weber bbfe0b79e2 Omit path to lld binary from lld's error, warning, and log output.
lld currently prepends the absolute path to itself to every diagnostic it
emits. This path can be longer than the diagnostic, and makes the actual error
message hard to read.

There isn't a good reason for printing this path: if you want to know which lld
you're running, pass -v to clang – chances are that if you're unsure of this,
you're not only unsure when it errors out. Some people want an indication that
the diagnostic is from the linker though, so instead print just the basename of
the linker's path.

Before:

```
$ out/bin/clang -target x86_64-unknown-linux -x c++ /dev/null -fuse-ld=lld 
/Users/thakis/src/llvm-mono/out/bin/ld.lld: error: cannot open crt1.o: No such file or directory
/Users/thakis/src/llvm-mono/out/bin/ld.lld: error: cannot open crti.o: No such file or directory
/Users/thakis/src/llvm-mono/out/bin/ld.lld: error: cannot open crtbegin.o: No such file or directory
/Users/thakis/src/llvm-mono/out/bin/ld.lld: error: unable to find library -lgcc
/Users/thakis/src/llvm-mono/out/bin/ld.lld: error: unable to find library -lgcc_s
/Users/thakis/src/llvm-mono/out/bin/ld.lld: error: unable to find library -lc
/Users/thakis/src/llvm-mono/out/bin/ld.lld: error: unable to find library -lgcc
/Users/thakis/src/llvm-mono/out/bin/ld.lld: error: unable to find library -lgcc_s
/Users/thakis/src/llvm-mono/out/bin/ld.lld: error: cannot open crtend.o: No such file or directory
/Users/thakis/src/llvm-mono/out/bin/ld.lld: error: cannot open crtn.o: No such file or directory
clang: error: linker command failed with exit code 1 (use -v to see invocation)
```

After:

```
$ out/bin/clang -target x86_64-unknown-linux -x c++ /dev/null -fuse-ld=lld 
ld.lld: error: cannot open crt1.o: No such file or directory
ld.lld: error: cannot open crti.o: No such file or directory
ld.lld: error: cannot open crtbegin.o: No such file or directory
ld.lld: error: unable to find library -lgcc
ld.lld: error: unable to find library -lgcc_s
ld.lld: error: unable to find library -lc
ld.lld: error: unable to find library -lgcc
ld.lld: error: unable to find library -lgcc_s
ld.lld: error: cannot open crtend.o: No such file or directory
ld.lld: error: cannot open crtn.o: No such file or directory
clang: error: linker command failed with exit code 1 (use -v to see invocation)
```

https://reviews.llvm.org/D49189

llvm-svn: 337634
2018-07-20 23:09:12 +00:00
Reid Kleckner 276d7167d0 [PDB] Write the command line after response file expansion
Summary: Fixes PR38085

Reviewers: ruiu, zturner

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D49566

llvm-svn: 337628
2018-07-20 22:34:20 +00:00
Takuto Ikuta d855928ec3 [PDB] Add PDBSourcePath flag to support absolutize source file path
This patch changes relative path for source files in obj files to
absolute path in PDB when linking with added flag.

I will make obj file generated by clang-cl independent from build
directory for chromium build. But I don't want to confuse visual studio
debugger or require additional configuration. To attain this goal, I
added flag to convert relative source file path in obj to absolute path
when emitting PDB.

By removing absolute path from obj files, we can share build cache
between chromium developers even when they are doing debug build.
That will make build time faster.

More context:
https://bugs.chromium.org/p/chromium/issues/detail?id=712796
https://groups.google.com/a/chromium.org/forum/#!topic/chromium-dev/5HXSVX-7fPc

llvm-svn: 337439
2018-07-19 04:56:22 +00:00
Rui Ueyama c93530d873 Look for an entry point function if /nodefaultlib is given.
Summary: Fixes https://bugs.llvm.org/show_bug.cgi?id=38018

Reviewers: thakis

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D48990

llvm-svn: 337407
2018-07-18 17:48:14 +00:00
Zachary Turner e2ce2a5c86 [coff] remove_dots from /PDBPATH but not /PDBALTPATH.
This more closely matches the behavior of link.exe, and also
simplifies the code slightly.

llvm-svn: 336882
2018-07-12 03:22:39 +00:00
Martin Storsjo 3a7905b2aa [COFF] Add an LLD specific option -debug:symbtab
With this set, we retain the symbol table, but skip the actual debug
information.

This is meant to be used by the MinGW frontend.

Differential Revision: https://reviews.llvm.org/D48745

llvm-svn: 335946
2018-06-29 06:08:25 +00:00
Reid Kleckner 3408568392 [COFF] Fix /wholearchive: to do libpath search again
Fixes https://crbug.com/852882

llvm-svn: 334761
2018-06-14 19:56:03 +00:00
Rui Ueyama 4eed6cc433 Fix /WholeArchive bug.
`lld-link foo.lib /wholearchive:foo.lib` should work the same way as
`lld-link /wholearchive:foo.lib foo.lib`. Previously, /wholearchive in
the former case was ignored.

Differential Revision: https://reviews.llvm.org/D47565

llvm-svn: 334552
2018-06-12 21:47:31 +00:00
Nico Weber d657c25649 lld-link: Implement /INTEGRITYCHECK flag
/INTEGRITYCHECK has the effect of setting
IMAGE_DLLCHARACTERISTICS_FORCE_INTEGRITY. Fixes PR31066.
https://reviews.llvm.org/D47472

llvm-svn: 333652
2018-05-31 13:43:02 +00:00
Sam Clegg 3ad27e92bc Code cleanup in preparation for adding LTO for wasm. NFC.
- Move some common code into Common/rrorHandler.cpp and
  Common/Strings.h.
- Don't use `fatal` when incompatible bitcode files are
  encountered.
- Rename NameRef variable to just Name

See D47162

Differential Revision: https://reviews.llvm.org/D47206

llvm-svn: 333021
2018-05-22 20:20:25 +00:00
Zachary Turner c8dd6ccc8a [COFF] Add /Brepro and /TIMESTAMP options.
Previously we would always write a hash of the binary into the
PE file, for reproducible builds.  This breaks AppCompat, which
is a feature of Windows that relies on the timestamp in the PE
header being set to a real value (or at the very least, a value
that satisfies certain properties).

To address this, we put the old behavior of writing the hash
behind the /Brepro flag, which mimics MSVC linker behavior.  We
also match MSVC default behavior, which is to write an actual
timestamp to the PE header.  Finally, we add the /TIMESTAMP
option (an lld extension) so that the user can specify the exact
value to be used in case he/she manually constructs a value which
is both reproducible and satisfies AppCompat.

Differential Revision: https://reviews.llvm.org/D46966

llvm-svn: 332613
2018-05-17 15:11:01 +00:00
Peter Collingbourne d25dfe9bda COFF: Add a flag for disabling string tail merging.
We discovered (crbug.com/838449#c24) that string tail merging can
negatively affect compressed binary size, so provide a flag to turn
it off for users who care more about compressed size than uncompressed
size.

Differential Revision: https://reviews.llvm.org/D46780

llvm-svn: 332149
2018-05-11 22:21:36 +00:00
Martin Storsjo 5c84d442f5 [COFF] Fix dangling StringRefs from SVN 331900
llvm-svn: 331912
2018-05-09 19:07:10 +00:00
Martin Storsjo 0ca06f7950 [COFF] Allow specifying export forwarding in a def file
Previously this was only supported when specified on the command line
or in directives.

Differential Revision: https://reviews.llvm.org/D46244

llvm-svn: 331900
2018-05-09 18:19:41 +00:00
Martin Storsjo 97379ff6b2 [COFF] Improve correctness of def parsing for GNU features
The operator == used for exporting a function with a different
name in the DLL compared to the name in the import library
(which is useful for adding linker level aliases for function
in the import library) is a feature distinct and different from
the operator = used for exporting a function with a different
name (both in import library and DLL) than in the implementation
producing the DLL.

When creating an import library using dlltool, from a def file that
contains forwards (Func = OtherDll.Func), this shouldn't affect the
produced import library, which should still behave just as if it
was a normal exported function.

This clears a lot of confusion and subtle misunderstandings, and
avoids a parameter that was used to avoid creating weak aliases
when invoked from lld. (This parameter was added previously due to
the existing conflation of the two features.)

Differential Revision: https://reviews.llvm.org/D46245

llvm-svn: 331860
2018-05-09 09:22:03 +00:00
Hans Wennborg 03ca8f4fd0 [COFF] Don't set the tsaware bit on DLLs
It doesn't apply to DLLs, and link.exe doesn't set it.

Differential Revision: https://reviews.llvm.org/D46077

llvm-svn: 330868
2018-04-25 20:32:00 +00:00
Bob Haarman 8832f88996 [COFF] create MemoryBuffers without requiring NUL terminators
Summary:
In a number of places in the COFF linker, we were calling
MemoryBuffer::getFile() with default parameters. This causes LLVM to
NUL-terminate the buffers, which can prevent them from being memory
mapped. Since we operate on binary and do not use NUL as an indicator
of the end of the file content, this change causes us to not require
the NUL terminator anymore.

Reviewers: ruiu, pcc

Reviewed By: ruiu

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45909

llvm-svn: 330786
2018-04-24 23:16:39 +00:00
Peter Collingbourne 3d636edc56 COFF: Merge .xdata into .rdata by default.
Differential Revision: https://reviews.llvm.org/D45804

llvm-svn: 330484
2018-04-20 21:32:37 +00:00
Peter Collingbourne 326f419335 COFF: Merge .bss into .data by default.
Differential Revision: https://reviews.llvm.org/D45803

llvm-svn: 330483
2018-04-20 21:30:36 +00:00
Peter Collingbourne fa322abee9 COFF: Rename Chunk::getPermissions to getOutputCharacteristics.
In an upcoming change I will need to make a distinction between section
type (code, data, bss) and permissions. The term that I use for both
of these things is "output characteristics".

Differential Revision: https://reviews.llvm.org/D45799

llvm-svn: 330361
2018-04-19 20:03:24 +00:00
Peter Collingbourne 66f1c9a858 Reland r330223, "COFF: Merge .idata, .didat and .edata into .rdata by default.", which was reverted in r330228.
In this reland I removed an unnecessary use of /debug in the test
delayimports32.test and used the /pdbaltpath flag in the test
pdb-publics-import.test, both of which avoid embedding absolute PDB
paths in executables which could affect later RVAs.

Original commit message:
> COFF: Merge .idata, .didat and .edata into .rdata by default.
>
> This saves a little space and matches what link.exe does.
>
> Tested using the chromium Windows trybots:
> https://chromium-review.googlesource.com/c/chromium/src/+/1014784

Differential Revision: https://reviews.llvm.org/D45737

llvm-svn: 330233
2018-04-17 23:28:52 +00:00
Peter Collingbourne 94aa62e48a COFF: Implement /pdbaltpath flag.
I needed to revert r330223 because we were embedding an absolute PDB
path in the .rdata section, which ended up being laid out before the
.idata section and affecting its RVAs. This flag will let us control
the embedded path.

Differential Revision: https://reviews.llvm.org/D45747

llvm-svn: 330232
2018-04-17 23:28:38 +00:00
Peter Collingbourne 1254f3e77c Revert r330223, "COFF: Merge .idata, .didat and .edata into .rdata by default."
Seems to have uncovered some sort of non-determinism on the bots.

llvm-svn: 330228
2018-04-17 22:16:39 +00:00
Peter Collingbourne 09e0e2e656 COFF: Merge .idata, .didat and .edata into .rdata by default.
This saves a little space and matches what link.exe does.

Tested using the chromium Windows trybots:
https://chromium-review.googlesource.com/c/chromium/src/+/1014784

Differential Revision: https://reviews.llvm.org/D45737

llvm-svn: 330223
2018-04-17 21:44:31 +00:00
Nico Weber fb64730005 s/LLVM_ON_WIN32/_WIN32/, lld
LLVM_ON_WIN32 is set exactly with MSVC and MinGW (but not Cygwin) in             
HandleLLVMOptions.cmake, which is where _WIN32 defined too.  Just use the        
default macro instead of a reinvented one.                                       
                                                                                 
See thread "Replacing LLVM_ON_WIN32 with just _WIN32" on llvm-dev and cfe-dev.   
No intended behavior change. 

llvm-svn: 329696
2018-04-10 13:15:21 +00:00
Nico Weber a764379458 [lld-link] Add comment explaining that /FIXED behavior is correct despite contradicting MSDN.
Also add a test for /FIXED.
https://reviews.llvm.org/D45087

llvm-svn: 328879
2018-03-30 17:17:04 +00:00
Nico Weber 0945ad6643 [lld-link] Let /PROFILE imply /OPT:REF /OPT:NOICF /INCREMENTAL:NO /FIXED:NO
/FIXED:NO is always the default, so that part needs no work.

Also test the interaction of /ORDER: with /INCREMENTAL.

https://reviews.llvm.org/D45091

llvm-svn: 328877
2018-03-30 17:14:50 +00:00
Zachary Turner f228276262 [PDB] Resubmit "Support embedding natvis files in PDBs."
This was reverted several times due to what ultimately turned out
to be incompatibilities in our serialized hash table format.

Several changes went in prior to this to fix those issues since
they were more fundamental and independent of supporting injected
sources, so now that those are fixed this change should hopefully
pass.

llvm-svn: 328363
2018-03-23 19:57:25 +00:00
Zachary Turner fced530650 Revert "Resubmit "Support embedding natvis files in PDBs.""
This is still failing on a different bot this time due to some
issue related to hashing absolute paths.  Reverting until I can
figure it out.

llvm-svn: 328014
2018-03-20 18:37:03 +00:00
Zachary Turner 132d7a134f Resubmit "Support embedding natvis files in PDBs."
The issue causing this to fail in certain configurations
should be fixed.

It was due to the fact that DIA apparently expects there to be
a null string at ID 1 in the string table.  I'm not sure why this
is important but it seems to make a difference, so set it.

llvm-svn: 328002
2018-03-20 17:06:39 +00:00
Zachary Turner a21558897b Revert "Support embedding natvis files in PDBs."
This is causing a test failure on a certain bot, so I'm removing
this temporarily until we can figure out the source of the error.

llvm-svn: 327903
2018-03-19 20:41:59 +00:00
Zachary Turner de53aaf132 Support embedding natvis files in PDBs.
Natvis is a debug language supported by Visual Studio for
specifying custom visualizers.  The /NATVIS option is an
undocumented link.exe flag which will take a .natvis file
and "inject" it into the PDB.  This way, you can ship the
debug visualizers for a program along with the PDB, which
is very useful for postmortem debugging.

This is implemented by adding a new "named stream" to the
PDB with a special name of /src/files/<natvis file name>
and simply copying the contents of the xml into this file.

Additionally, we need to emit a single stream named
/src/headerblock which contains a hash table of embedded
files to records describing them.

This patch adds this functionality, including the /NATVIS
option to lld-link.

Differential Revision: https://reviews.llvm.org/D44328

llvm-svn: 327895
2018-03-19 19:53:51 +00:00
Martin Storsjo 5351891b55 [COFF] Add support for the GNU ld flag --kill-at
GNU ld has got a number of different flags for adjusting how to
behave around stdcall functions. The --kill-at flag strips the
trailing sdcall suffix from exported functions (which otherwise
is included by default in MinGW setups).

This also strips it from the corresponding import library though.
That makes it hard to link to such an import library from code
that calls the functions - but this matches what GNU ld does with
this flag. Therefore, this flag is probably not sensibly used
together with import libraries, but probably mostly when creating
some sort of plugin, or if creating the import library separately
with dlltool.

Differential Revision: https://reviews.llvm.org/D44292

llvm-svn: 327561
2018-03-14 20:17:16 +00:00
Nico Weber f06ae4f3b4 Make lld-link shout at me less.
This makes the output of some flag names in warning messages consistent with
the output of /? and the output of flags in most other diagnostics.

https://reviews.llvm.org/D44307

llvm-svn: 327261
2018-03-12 12:45:40 +00:00
Nico Weber 11a6db3027 [lld-link] For suppressible warnings, print the warning number.
The warning can be suppressed by passing the number to /ignore:.
https://reviews.llvm.org/D44297

llvm-svn: 327257
2018-03-12 12:04:17 +00:00
Nico Weber 0771c604c9 [lld-link] Add support for /ignore:4037.
Fixes PR36657.
https://reviews.llvm.org/D44286

llvm-svn: 327124
2018-03-09 12:41:04 +00:00
Rui Ueyama cdd5fb5087 Report an error if you try to link against .dll instead of .lib.
It is a usage error to feed a .dll file instead of a .dll to COFF linker.
Previously, lld failed with a mysterious error message. Now we reject
it at the driver.

Fixes https://bugs.llvm.org/show_bug.cgi?id=36440

Differential Revision: https://reviews.llvm.org/D43964

llvm-svn: 326507
2018-03-01 23:11:30 +00:00
Sam Clegg f187c4d2e5 Consistent use of header file for ICF and MarkLive
Previously wasm used a separate header to declare markLive
and ELF used to declare ICF.  This change makes each backend
consistently declare these in their own headers.

Differential Revision: https://reviews.llvm.org/D43529

llvm-svn: 325631
2018-02-20 22:09:59 +00:00
Sam Clegg 3141ddc58d Consistent (non) use of empty lines in include blocks
The profailing style in lld seem to be to not include such empty lines.
Clang-tidy/clang-format seem to handle this just fine.

Differential Revision: https://reviews.llvm.org/D43528

llvm-svn: 325629
2018-02-20 21:53:18 +00:00
Benjamin Kramer 6400a97418 [COFF] LTO does not require a disassembler.
llvm-svn: 324355
2018-02-06 15:42:41 +00:00
Reid Kleckner af2f7da74c [COFF] Add minimal support for /guard:cf
Summary:
This patch adds some initial support for Windows control flow guard. At
the end of the day, the linker needs to synthesize a table of RVAs very
similar to the structured exception handler table (/safeseh).

Both /safeseh and /guard:cf take sections of symbol table indices
(.sxdata and .gfids$y) and turn them into RVA tables referenced by the
load config struct in the CRT through special symbols.

Reviewers: ruiu, amccarth

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D42592

llvm-svn: 324306
2018-02-06 01:58:26 +00:00
Bob Haarman 5ec448516d [COFF] make /incremental control overwriting unchanged import libraries
Summary:
r323164 made lld-link not overwrite import libraries when their
contents haven't changed. MSVC's link.exe does this only when
performing incremental linking. This change makes lld-link's import
library overwriting similarly dependent on whether or not incremental
linking is being performed. This is controlled by the /incremental or
/incremental:no options. In addition, /opt:icf, /opt:ref, and /order
turn off /incremental and issue a warning if /incremental was
specified on the command line.

Reviewers: rnk, ruiu, zturner

Reviewed By: ruiu

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D42716

llvm-svn: 323930
2018-01-31 23:44:00 +00:00
Martin Storsjo cf47b046f9 [COFF] Remove the temporary file if not updating the import library
Differential Revision: https://reviews.llvm.org/D42621

llvm-svn: 323725
2018-01-30 07:26:01 +00:00
Rui Ueyama b6d3a93594 Warn on nonexistent comdat sections in an /order file.
I didn't implement the feature in the original patch because I didn't
come up with an idea to do that easily and efficiently. Turned out that
that is actually easy to implement.

In this patch, we collect comdat sections before gc is run and warn on
nonexistent symbols in an order file.

Differential Revision: https://reviews.llvm.org/D42658

llvm-svn: 323699
2018-01-29 21:50:53 +00:00
Rui Ueyama d73479ba12 Remove trailing space.
llvm-svn: 323682
2018-01-29 19:55:55 +00:00
Rui Ueyama 57175aa1e9 Add the /order option.
With the /order option, you can give an order file. An order file
contains symbol names, one per line, and the linker places comdat
sections in that given order. The option is used often to optimize
an output binary for (in particular, startup) speed by improving
locality.

Differential Revision: https://reviews.llvm.org/D42598

llvm-svn: 323579
2018-01-27 00:34:46 +00:00
Bob Haarman 4ce341ffb6 [COFF] don't replace import library if contents are unchanged
Summary:
This detects when an import library is about to be overwritten with a
newly built one with the same contents, and keeps the old library
instead. The use case for this is to avoid needlessly rebuilding
targets that depend on the import library in build systems that rely
on timestamps to determine whether a target requires rebuilding.

This feature was requested in PR35917.

Reviewers: rnk, ruiu, zturner, pcc

Reviewed By: ruiu

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D42326

llvm-svn: 323164
2018-01-23 00:36:42 +00:00
Martin Storsjo 3b611fa93f [COFF] Keep the underscore on exported decorated stdcall functions in MSVC mode
This fixes PR35733.

Differential Revision: https://reviews.llvm.org/D41632

llvm-svn: 323036
2018-01-20 11:44:42 +00:00
Zachary Turner 727f153b6f [coff] Print detailed timing information with /TIME.
The classes used to print and update time information are in
common, so other linkers could use this as well if desired.

Differential Revision: https://reviews.llvm.org/D41915

llvm-svn: 322736
2018-01-17 19:16:26 +00:00
Rui Ueyama 5fa0d6e4a2 [COFF] Process /EXPORT option in fastpath
Patch by Takuto Ikuta.

This patch reduces lld link time of chromium's blink_core.dll in
component build.

Total size of input argument in .directives become nearly 300MB in the
build and almost all its content are /EXPORT.

To reduce time of parsing too many /EXPORT option in the build, I
introduce fastpath for /EXPORT in ArgParser::parseDirectives.

On my desktop machine, 4 times stats of the link time are like below.
Improved around 20%.

This patch
TotalSeconds : 8.6217627
TotalSeconds : 8.5402175
TotalSeconds : 8.6855853
TotalSeconds : 8.3624441
Ave : 8.5525024

master
TotalSeconds : 10.9975031
TotalSeconds : 11.3409428
TotalSeconds : 10.6332897
TotalSeconds : 10.7650687
Ave : 10.934201075

llvm-svn: 322117
2018-01-09 20:36:42 +00:00
Shoaib Meenai 7e3e28f968 [COFF] Delete CanExitEarly
It was being set but never used, and its value is only ever needed
locally in lld::coff::link.

Differential Revision: https://reviews.llvm.org/D41814

llvm-svn: 322026
2018-01-08 21:14:51 +00:00
Shoaib Meenai fd3e4b0ea1 [COFF] Initalize ErrorHandler with CanExitEarly value
Previously, the COFF driver would call exit(1) from the
ErrorHandler in the case of a link error, even if
CanExitEarly=false was specified. Now it initializes
the ErrorHandler in the same way that the ELF driver does.

Patch by Andrew Kelley.

Differential Revision: https://reviews.llvm.org/D41803

llvm-svn: 321983
2018-01-08 05:58:36 +00:00
Rui Ueyama a63eed0f80 Do not parse the same /export string more than once.
Differential Revision: https://reviews.llvm.org/D41607

llvm-svn: 321513
2017-12-28 07:41:19 +00:00
Bob Haarman e90ac016e7 [COFF] support /ignore:4217
Summary:
lld-link accepts link.exe's /ignore option, but used to ignore
it. This can lead to semantic differences when warnings are treated as
fatal errors. One such case is when we resolve an __imp_ symbol to a
local definition. We emit a warning in that case, which /wx turns into
a fatal. This change makes lld-link accept /ignore:4217 to suppress
that warning, so that code that links with link.exe /wx /ignore:4217
links with lld-link, too.

Fixes PR35762.

Reviewers: rnk, ruiu

Reviewed By: ruiu

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D41606

llvm-svn: 321512
2017-12-28 07:02:13 +00:00
Rui Ueyama 130eb04689 [COFF] Do not parse args twice if no rsp files exists
Patch by Takuto Ikuta.

This patch reduces link time of chromium's blink_core.dll in component
build. Total size of input argument in .directives become nearly 300MB
in the build and no rsp file is used. Speedup link by skipping duplicate
parsing.

On my desktop machine, 4 times stats are like below. Improved around 15%.

This patch
TotalSeconds : 18.408538
TotalSeconds : 17.2996744
TotalSeconds : 17.1053862
TotalSeconds : 17.809777
avg: 17.6558439

master
TotalSeconds : 20.9290504
TotalSeconds : 19.9158213
TotalSeconds : 21.0643515
TotalSeconds : 20.8775831
avg: 20.696701575

Differential Revision: https://reviews.llvm.org/D41581

llvm-svn: 321470
2017-12-27 06:08:10 +00:00
Shoaib Meenai a1f6fba4d1 [COFF] Clean up debug option handling
/debug and /debug:dwarf are orthogonal. An object file can contain both
CodeView and DWARF debug info, so the combination of /debug:dwarf and
/debug should generate both DWARF and a PDB, rather than /debug:dwarf
always suppressing PDB creation.

/nopdb is now redundant and can be removed. /debug /nopdb was previously
used to support DWARF, but specifying /debug:dwarf is entirely
equivalent to that combination now.

Differential Revision: https://reviews.llvm.org/D41310

llvm-svn: 320896
2017-12-16 00:23:24 +00:00
Shoaib Meenai c4fdbca604 [COFF] Update an outdated comment. NFC
This comment dates from when LLD didn't produce actual PDBs, and is very
outdated now.

llvm-svn: 320894
2017-12-15 23:52:46 +00:00
Shoaib Meenai 111db7945d [COFF] Simplify hasArgs calls. NFC
We can just pass multiple options to hasArgs (which will check for any
of those options being present) instead of calling it multiple times.

llvm-svn: 320892
2017-12-15 23:51:14 +00:00
Zachary Turner 0d07a8e948 [COFF] Teach LLD to use the COFF .debug$H section.
This adds the /DEBUG:GHASH option to LLD which will look for
the existence of .debug$H sections in linker inputs and use them
to accelerate type merging.  The clang-cl side has already been
added, so this completes the work necessary to begin experimenting
with this feature.

Differential Revision: https://reviews.llvm.org/D40980

llvm-svn: 320719
2017-12-14 18:07:04 +00:00
Martin Storsjo 6ea167cc43 [COFF] Disallow -dynamicbase:no for arm and arm64
This matches what MSVC link.exe does.

Differential Revision: https://reviews.llvm.org/D41051

llvm-svn: 320517
2017-12-12 19:39:13 +00:00
Martin Storsjo 2b964108a0 [COFF] Don't error out on undefined references to __enclave_config
This is required for linking the CRT from MSVC 2017 15.5.

Differential Revision: https://reviews.llvm.org/D41089

llvm-svn: 320462
2017-12-12 08:22:29 +00:00
Rui Ueyama b59ceb1068 Do not read the same .lib file more than once.
In the following command line,

  lld-link foo/bar.lib /defaultlib:bar.lib

"/defaultlib:bar.lib" should be a nop even if a file with the same
name exists in other library search path.

Fixes https://bugs.llvm.org/show_bug.cgi?id=35476

Differential Revision: https://reviews.llvm.org/D41094

llvm-svn: 320434
2017-12-11 23:09:18 +00:00
Rui Ueyama bdc5150984 Always evaluate the second argument for CHECK() lazily.
This patch is to rename check CHECK and make it a C macro, so that
we can evaluate the second argument lazily.

Differential Revision: https://reviews.llvm.org/D40915

llvm-svn: 319974
2017-12-06 22:08:17 +00:00
Sam Clegg 7e7566323d toString function take a const refs where possible
Differential Revision: https://reviews.llvm.org/D40824

llvm-svn: 319787
2017-12-05 16:50:46 +00:00
Reid Kleckner 3e89b08303 Revert "Merge .xdata into .rdata by default"
This reverts commit r318699, it is breaking 32-bit SEH handlers in
Chromium.

llvm-svn: 319508
2017-12-01 01:04:31 +00:00
Rui Ueyama 215286f2a4 [LLD] [COFF] Support ENTRY and SUBSYSTEM in .drectve sections
Adds support for "/ENTRY" and "/SUBSYSTEM" linker options in .drectve
sections. Some Mozilla binaries were using these directives and MSVC
link.exe appears to allow them. No attempt is made to reconcile these
with the options on the command line.

Patch by David Major!

Differential Revision: https://reviews.llvm.org/D39972

llvm-svn: 319356
2017-11-29 20:46:13 +00:00
Rui Ueyama 2017d52b54 Move Memory.{h,cpp} to Common.
Differential Revision: https://reviews.llvm.org/D40571

llvm-svn: 319221
2017-11-28 20:39:17 +00:00
Peter Collingbourne f874bd67d8 COFF: Emit a COFF symbol table if /debug:dwarf is specified.
This effectively reverts r318548 and r318635 while keeping the
functionality behind the flag and preserving the bug fix from r318548.

Differential Revision: https://reviews.llvm.org/D40264

llvm-svn: 318721
2017-11-21 01:14:14 +00:00
Reid Kleckner 95cc796cf1 Merge .xdata into .rdata by default
Summary: MSVC does this. The user can override it with their own /merge: flag.

Reviewers: ruiu, pcc

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D40197

llvm-svn: 318699
2017-11-20 21:49:35 +00:00
Peter Collingbourne 5e80bdebd2 COFF: Stop emitting a non-standard COFF symbol table into PEs.
Now that our support for PDB emission is reasonably good, there is
no longer a need to emit a COFF symbol table.

Also fix a bug where we would fail to emit a string table for long
section names if /debug was not specified.

Differential Revision: https://reviews.llvm.org/D40189

llvm-svn: 318548
2017-11-17 19:51:20 +00:00
Reid Kleckner 5883989e51 Remove a std::map and std::set that show up in LLD profiles
For GC roots, add a bit to SymbolBody to ensure that we don't add the
same root twice, and switch to a vector. In addition to being faster,
this may also fix some latent non-determinism. We iterate the GCRoot
list later and it the order should be deterministic.

For fixupExports, we can just use DenseMap. This is a simple string
uniquing task, and we don't iterate the map.

Reviewers: ruiu

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D39609

llvm-svn: 318072
2017-11-13 18:38:53 +00:00
Reid Kleckner c2dcdd852b Disable GC and ICF when /debug is present
ICF and GC impair debugging, so MSVC disables these optimizations when
/debug is passed. They are still on by default when no PDB is produced.

This change also makes /opt:ref enable ICF, which is consistent with
MSVC: https://msdn.microsoft.com/en-us/library/bxwfs976.aspx

We should consider making /opt:icf fold readonly data in the near
future. LLD used to do this, but we disabled it because it breaks too
many programs. MSVC only does this if the user explicitly passes
/opt:icf.

Reviewers: ruiu, pcc

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D39885

llvm-svn: 318071
2017-11-13 18:38:25 +00:00
Martin Storsjo 068512dfb9 [MinGW] Output debug info by default, unless the -s parameter is passed
Differential Revision: https://reviews.llvm.org/D39541

llvm-svn: 317376
2017-11-03 22:10:37 +00:00
Rui Ueyama f52496e1e0 Rename SymbolBody -> Symbol
Now that we have only SymbolBody as the symbol class. So, "SymbolBody"
is a bit strange name now. This is a mechanical change generated by

  perl -i -pe s/SymbolBody/Symbol/g $(git grep -l SymbolBody lld/ELF lld/COFF)

nd clang-format-diff.

Differential Revision: https://reviews.llvm.org/D39459

llvm-svn: 317370
2017-11-03 21:21:47 +00:00
Martin Storsjo dc95dbfcab [COFF] Autoexport symbols as data if they don't point to an executable section
This was already taken care of for the output def file.

Differential Revision: https://reviews.llvm.org/D39573

llvm-svn: 317367
2017-11-03 20:58:20 +00:00
Rui Ueyama 616cd99194 [COFF] Merge Symbol and SymbolBody.
llvm-svn: 317007
2017-10-31 16:10:24 +00:00
Bob Haarman b8a59c8aa5 [lld] unified COFF and ELF error handling on new Common/ErrorHandler
Summary:
The COFF linker and the ELF linker have long had similar but separate
Error.h and Error.cpp files to implement error handling. This change
introduces new error handling code in Common/ErrorHandler.h, changes the
COFF and ELF linkers to use it, and removes the old, separate
implementations.

Reviewers: ruiu

Reviewed By: ruiu

Subscribers: smeenai, jyknight, emaste, sdardis, nemanjai, nhaehnle, mgorny, javed.absar, kbarton, fedor.sergeev, llvm-commits

Differential Revision: https://reviews.llvm.org/D39259

llvm-svn: 316624
2017-10-25 22:28:38 +00:00
Peter Collingbourne acc3baaea1 COFF: Don't add /manifest* flags to the response file.
If /manifest:embed is enabled we're already creating a resource file
out of these flags and adding it to the linkrepro, and it doesn't
seem worth being able to repro side-by-side manifests.

Includes a test that covers this commit as well as r315948.

Differential Revision: https://reviews.llvm.org/D38975

llvm-svn: 316547
2017-10-25 05:00:54 +00:00
Shoaib Meenai 59bf362974 [COFF] Clean up boolean flag handling
LLD's handling of boolean flags is suboptimal:
* All boolean flags have a corresponding `:no` flag to turn the flag
  off, and the linker should scan for both the non-suffixed and suffixed
  flags (and the last one should win), but right now it only scans for
  either the suffixed or non-suffixed flag (depending on the default
  flag value).
* The `B` multiclass only allows specifying help text for the suffixed
  (`:no`) flag, but for some flags (e.g. `/appcontainer`) the help text
  should be associated with the non-suffixed flag instead.

Extend the `B` multiclass to have help text for both non-suffixed and
suffixed flag variants, and alter the existing help text accordingly in
some cases. Scan for both the non-suffixed and suffixed variants in the
driver and set config values accordingly.

This should mostly have no behavior change, apart from the added help
text and the modified argument scanning. Some flags are handled slightly
differently now, however; for example, LLD would previously always treat
64-bit images as large address aware, whereas `/largeaddressaware:no` is
now respected for 64-bit images (which is also how link.exe behaves).

Differential Revision: https://reviews.llvm.org/D39216

llvm-svn: 316501
2017-10-24 21:17:16 +00:00
Rui Ueyama 6f4e255219 lld::COFF: better behavior when using as a library
Previously, the COFF driver would call exit(0) when called
as a library.  Now it takes `ExitEarly` option, and if it
is false, it doesn't exit.  So it is now more library-friendly.

Furthermore, link() calls freeArena() before returning, to
clean up resources.

Based on an Andrew Kelley's patch.

Differential Revision: https://reviews.llvm.org/D39202

llvm-svn: 316370
2017-10-23 20:03:32 +00:00
Rui Ueyama a4cf97bc9c Add the --version option.
Differential Revision: https://reviews.llvm.org/D38972

llvm-svn: 316329
2017-10-23 14:57:53 +00:00
Martin Storsjo ddb094ad36 [COFF] Fix exporting of functions starting with underscores, etc
This fixes exporting functions in the following cases:
- functions starting with an underscore in def files
- functions starting with an underscore, via dllexport attributes, for mingw
- fastcall and vectorcall functions when declared undecorated in def files
- vectorcall functions when declared decorated in def files
- stdcall functions when declared decorated in def files for mingw

This still exports the stdcall functions with the wrong name
in the normal msvc/link.exe mode, if declared with decoration in
the def file though (this is not a regression though). Exporting
functions via def files including decoration is not something I
believe is routinely done though, but is tested to try to match
link.exe's behaviour as far as easily possible.

Differential Revision: https://reviews.llvm.org/D39170

llvm-svn: 316317
2017-10-23 09:08:24 +00:00
Martin Storsjo e1f894d59e [COFF] Move MinGW specific functions/classes to a separate file. NFC.
Differential Revision: https://reviews.llvm.org/D39067

llvm-svn: 316178
2017-10-19 19:49:38 +00:00
Martin Storsjo b40ccc1c58 [COFF] Exclude certain static libraries and object files when exporting all symbols
This more or less matches what GNU ld does.

Differential Revision: https://reviews.llvm.org/D38937

llvm-svn: 316148
2017-10-19 06:56:04 +00:00
Peter Collingbourne 9362ac60bc COFF: Add resource files to linkrepro instead of the cvtres object file.
Now that we have our own implementation of cvtres, we can add resource
files directly to the linkrepro.

Differential Revision: https://reviews.llvm.org/D38974

llvm-svn: 315954
2017-10-16 23:15:04 +00:00
Martin Storsjo 6e8acc25d0 [COFF] Fix indentation. NFC.
llvm-svn: 315879
2017-10-15 21:09:46 +00:00
Martin Storsjo e401aa93c8 [COFF] Fix the description of the data type in a comment. NFC.
This was missed when changing data types back and forth during
review.

llvm-svn: 315878
2017-10-15 21:09:43 +00:00
Martin Storsjo 7f71acdcd7 [COFF] Add support for automatically exporting all symbols
GNU ld automatically exports all symbols if no symbols have
been chosen to export via either def files or dllexport attributes.
The same behaviour can also be enabled via the GNU ld option
--export-all-symbols, in case some symbols are marked for export
via a def file or dllexport attribute.

The list of excluded symbols is from GNU ld, minus the
cygwin specific symbols.

Also add support for outputting the actual list of exported
symbols in a def file, as in the GNU ld option --output-def.

These options in GNU ld are documented in
https://sourceware.org/binutils/docs/ld/WIN32.html.

This currently exports all symbols from object files pulled in
from libmingw32 and libmingwex and other static libraries
that are linked in.

Differential Revision: https://reviews.llvm.org/D38760

llvm-svn: 315562
2017-10-12 05:37:13 +00:00
Rui Ueyama cc6738a439 Use error() instead of warn() to report undefined symbols.
I believe the reason why we used warn() instead of error() to report
undefined symbols is because the older implementation of error() exitted
immediately. Here, we want to find as many undefined symbols as we can,
so I chose to use warn() instead of error().

Now error() does not exit immediately, so it doesn't make sense to keep
them as warnings.

Differential Revision: https://reviews.llvm.org/D38652

llvm-svn: 315131
2017-10-06 23:43:54 +00:00
Rui Ueyama 3f851704c1 Move new lld's code to Common subdirectory.
New lld's files are spread under lib subdirectory, and it isn't easy
to find which files are actually maintained. This patch moves maintained
files to Common subdirectory.

Differential Revision: https://reviews.llvm.org/D37645

llvm-svn: 314719
2017-10-02 21:00:41 +00:00
Rafael Espindola 474f2bdabe Update for llvm change.
llvm-svn: 313938
2017-09-21 23:13:40 +00:00
Shoaib Meenai 4aa7f8a30f [COFF] Check for sections larger than 4 GiB
Sections are limited to 4 GiB. Error out early if a section exceeds this
size, rather than overflowing the section size and getting confusing
assertion failures/segfaults later.

Differential Revision: https://reviews.llvm.org/D38005

llvm-svn: 313699
2017-09-19 23:58:05 +00:00
Rui Ueyama eef6b2a5c9 Revert r303378: Set IMAGE_DLL_CHARACTERISTICS_NO_BIND.
r303378 was submitted because r303374 (Merge IAT and ILT) made lld's
output incompatible with the Binding feature. Now that r303374 was
reverted, we do not need to keep this change.

Pointed out by pcc.

llvm-svn: 313414
2017-09-15 22:49:13 +00:00
Rui Ueyama cfc2f80df6 Remove {get,set}Align accessor functions and use Alignment member variable instead.
llvm-svn: 313204
2017-09-13 21:54:55 +00:00
Rui Ueyama a835babef9 Do not use hasArgNoClaim().
Arg instances can be claimed. After claimed, its `isClaimed` function
returns true. We do not use that notion in lld, so using NoClaim
versions of functions is just confusing. This patch is to just use
hasArg instead of hasArgNoClaim.

llvm-svn: 313187
2017-09-13 20:30:59 +00:00
Martin Storsjo 31fe4cd25d [MinGW] Support dllexport on i386
In MinGW configurations (GCC, or clang with a *-windows-gnu target),
the -export directives in the object file contains the undecorated
symbol name, while it is decorated in MSVC configurations. (On the
command line, link.exe takes an undecorated symbol name for the
-export argument though.)

Differential Revision: https://reviews.llvm.org/D37772

llvm-svn: 313174
2017-09-13 19:29:39 +00:00
Martin Storsjo 8278ba51d3 [COFF] Add support for the -wholearchive option
This fixes PR31824.

Differential Revision: https://reviews.llvm.org/D37709

llvm-svn: 313123
2017-09-13 07:28:03 +00:00
Rui Ueyama 9d9bdabee3 Ignore /natvis option for now.
/natvis is a new command line option introduced by MSVC 2017.
We eventually have to support it, but for now, let's ignore it so that
we can at least link stuff instead of printing out an error.

Patch by Michael Rickert.

llvm-svn: 312966
2017-09-11 22:24:13 +00:00
Peter Collingbourne 052e855e2b COFF: Implement ThinLTO cache and cache pruning support.
Differential Revision: https://reviews.llvm.org/D37607

llvm-svn: 312770
2017-09-08 00:50:50 +00:00
Peter Collingbourne cef809938d COFF: Remove unnecessary casts. NFCI.
llvm-svn: 312762
2017-09-07 23:49:09 +00:00
Nico Weber a05cbb8b95 lld-link: Add --rsp-quoting= flag.
This ports https://reviews.llvm.org/D19425 from clang /
https://reviews.llvm.org/D22015 from the ELF port to COFF lld. This can be
useful when linking COFF files on a posix host.

https://reviews.llvm.org/D37452

llvm-svn: 312594
2017-09-05 23:46:45 +00:00
Rui Ueyama 01d0265106 Simplify writeArchive return type.
writeArchive returned a pair, but the first element of the pair is always
its first argument on failure, so it doesn't make sense to return it from
the function. This patch change the return type so that it does't return it.

Differential Revision: https://reviews.llvm.org/D37313

llvm-svn: 312177
2017-08-30 22:11:03 +00:00
Rui Ueyama f59b709ae4 Move a function from Driver.cpp to InputFile.cpp.
This patch doesn't improve code per se, but it should make the following
patch's diff easier to read.

llvm-svn: 312170
2017-08-30 20:55:18 +00:00
Rui Ueyama cbf969eb20 Remove Symtab aliases.
Various classes have `Symtab` member variables even though we have
lld::coff::Symtab variable because previous attempts to make COFF lld's
internal structure resemble to ELF's was incomplete. This patch finishes
that job by removing member variables.

llvm-svn: 311938
2017-08-28 21:51:07 +00:00
Rui Ueyama affb40e9d2 Keep an instance of COFFOptTable alive as long as InputArgList is alive.
Summary:
ArgParser created an instance of COFFOptTable on stack to use it to
parser command line arguments. Parsed arguments were then returned from
the function as InputArgList. This was safe because InputArgList referred
only statically-allocated InfoTable.

That is not a safe assumption after https://reviews.llvm.org/D36782,
which changes the type of its internal table from ArrayRef to std::vector.
To make lld work with that patch, we need to keep an instance of
COFFOptTable at least as long as an InputArgList is alive. This patch
does that.

Reviewers: yamaguchi

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D37217

llvm-svn: 311930
2017-08-28 20:46:30 +00:00
Rui Ueyama 8bee41e423 Simplify. NFC.
llvm-svn: 311700
2017-08-24 20:32:58 +00:00
Rui Ueyama 9f7032aaf0 Minor refactoring. NFC.
llvm-svn: 311696
2017-08-24 20:26:54 +00:00
Martin Storsjo 92f32d0c53 [COFF] Don't produce weak aliases in import libraries
When creating an import library from lld, the cases with
Name != ExtName shouldn't end up as a weak alias, but as a real
export of the new name, which is what actually is exported from
the DLL.

This restores the behaviour of renamed exports to what it was in
4.0.

Differential Revision: https://reviews.llvm.org/D36634

llvm-svn: 310992
2017-08-16 05:23:00 +00:00
Martin Storsjo a50275cfe5 [COFF] Fix the name type for stdcall functions in import libraries
Since SVN r303491 and r304573, LLD used the COFFImportLibrary
functions from LLVM. These only had two names, Name and ExtName,
which wasn't enough to convey all the details of stdcall functions.

Stdcall functions got the wrong symbol name in the import library
itself in r303491, which is why it was reverted in r304561. When
re-landed and fixed in r304573 (after adding a test in r304572),
the symbol name itself in the import library ended up right, but the
name type of the import library entry was wrong.

This had the effect that linking to the import library succeeded
(contrary to in r303491, where linking to such an import library
failed), but at runtime, the symbol wouldn't be found in the DLL
(since the caller linked to the stdcall decorated name).

Differential Revision: https://reviews.llvm.org/D36545

llvm-svn: 310989
2017-08-16 05:13:25 +00:00
Martin Storsjo d2752aa9ec [COFF] Add support for aligncomm directives
These are emitted for comm symbols in object files, when targeting
a GNU environment.

Alternatively, just ignore them since we already align CommonChunk
to the natural size of the content (up to 32 bytes). That would only
trade away the possibility to overalign small symbols, which doesn't
sound like something that might not need to be handled?

Differential Revision: https://reviews.llvm.org/D36304

llvm-svn: 310871
2017-08-14 19:07:27 +00:00
Rui Ueyama acd632d338 Add {Obj,Import,Bitcode}File::Instances to COFF input files.
We did the same thing for ELF in r309152, and I want to maintain
COFF and ELF as close as possible.

llvm-svn: 309239
2017-07-27 00:45:26 +00:00
Rui Ueyama e1b48e099c Rename ObjectFile ObjFile for COFF as well.
llvm-svn: 309228
2017-07-26 23:05:24 +00:00
Nico Weber a7a2c44e70 lld: only write .manifest files if /manifest is passed, PR33925
Also emit an error if /manifestinput: is used without /manifest:embed.
Increases compatibility with link.exe

https://reviews.llvm.org/D35842

llvm-svn: 308998
2017-07-25 18:08:03 +00:00
Rui Ueyama 12234f8093 Use StringRef::contains().
llvm-svn: 308526
2017-07-19 21:40:26 +00:00
Rui Ueyama 38b0f4a1f2 Handle option aliases in a better way.
In this way, we don't need to know which options have aliases.

llvm-svn: 308519
2017-07-19 20:30:04 +00:00
Saleem Abdulrasool ace2fa7da4 COFF: improve link conformance for import names
Improve the link conformance for the import name embedded into the
import library.  This requires the associated change to the LLVM portion
for the DEF file parser.  The import file generation embeds a different
name based on whether the driver is invoked as "link" or "lib".
Furthermore, the LIBRARY keyword in the DEF file influences the import
name.  The behaviour can be summarised according to the following table:

      | LIBRARY w/ ext |   LIBRARY w/o ext   | no LIBRARY
 -----+----------------+---------------------+------------------
 LINK | {value}        | {value}.{.dll/.exe} | {output name}
  LIB | {value}        | {value}.dll         | {output name}.dll

llvm-svn: 308407
2017-07-19 02:01:27 +00:00
Zachary Turner 6708e0b45e [lld/pdb] Add some basic linker module symbols.
Differential Revision: https://reviews.llvm.org/D35152

llvm-svn: 307590
2017-07-10 21:01:37 +00:00
Reid Kleckner 502d4ce2e4 [COFF] Improve synthetic symbol handling
Summary:
The main change is that we can have SECREL and SECTION relocations
against ___safe_se_handler_table, which is important for handling the
debug info in the MSVCRT.

Previously we were using DefinedRelative for __safe_se_handler_table and
__ImageBase, and after we implement CFGuard, we plan to extend it to
handle __guard_fids_table, __guard_longjmp_table, and more.  However,
DefinedRelative is really only suitable for implementing __ImageBase,
because it lacks a Chunk, which you need in order to figure out the
output section index and output section offset when resolving SECREl and
SECTION relocations.

This change renames DefinedRelative to DefinedSynthetic and gives it a
Chunk. One wart is that __ImageBase doesn't have a chunk. It points to
the PE header, effectively. We could split DefinedRelative and
DefinedSynthetic if we think that's cleaner and creates fewer special
cases.

I also added safeseh.s, which checks that we don't emit a safe seh table
entries pointing to garbage collected handlers and that we don't emit a
table at all when there are no handlers.

Reviewers: ruiu

Reviewed By: ruiu

Subscribers: inglorion, pcc, llvm-commits, aprantl

Differential Revision: https://reviews.llvm.org/D34577

llvm-svn: 306293
2017-06-26 15:39:52 +00:00
Rui Ueyama 2f740f74bb Define __guard_{iat,longjmp}_{count,table} symbols.
VC2017 contains these new symbols as undefined symobls. They are used
for /guard:cf. Since we do not support the control flow guard, but we
want to at least ignore these symbols so that we can link against VS2017
libraries.

Fixes https://bugs.chromium.org/p/chromium/issues/detail?id=727193.

llvm-svn: 305876
2017-06-21 02:26:19 +00:00
Eric Beckmann 9e19d790a6 Update documentation to reflection disuse of external cvtres.
Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D34316

llvm-svn: 305631
2017-06-17 02:26:27 +00:00
Zachary Turner 7ba50b7151 Remove /dumppdb option from LLD.
This option is no longer needed.

Differential Revision: https://reviews.llvm.org/D34302

llvm-svn: 305610
2017-06-16 23:41:44 +00:00
Saleem Abdulrasool bc7ff7027e COFF: add support for lib mode usage
When link is invoked with `/def:` and no input files, it behaves as if
`lib.exe` was invoked.  Emulate this behaviour, generating the import
library from the def file that was passed.  Because there is no input to
actually generate the dll, we simply process the def file early and exit
once we have created the import library.

llvm-svn: 305502
2017-06-15 20:39:58 +00:00
Rui Ueyama 2aecdde512 Inline a small function. NFC.
llvm-svn: 305428
2017-06-14 23:37:37 +00:00
Rui Ueyama 67aea737f3 Use check() to report an error.
llvm-svn: 305033
2017-06-08 23:43:44 +00:00
Zachary Turner 264b5d9e88 Move Object format code to lib/BinaryFormat.
This creates a new library called BinaryFormat that has all of
the headers from llvm/Support containing structure and layout
definitions for various types of binary formats like dwarf, coff,
elf, etc as well as the code for identifying a file from its
magic.

Differential Revision: https://reviews.llvm.org/D33843

llvm-svn: 304864
2017-06-07 03:48:56 +00:00
Reid Kleckner 146eb7a65f Re-land "COFF: migrate def parser from LLD to LLVM"
This reverts commit r304561 and re-lands r303490 & co.

The fix was to use "SymbolName" when translating LLD's internal export
list to lib/Object's short export struct. The SymbolName reflects the
actual symbol name, which may include fastcall and stdcall mangling bits
not included in the /EXPORT or .def file EXPORTS name:

@@ -434,8 +434,7 @@ std::vector<COFFShortExport> createCOFFShortExportFromConfig() {
   std::vector<COFFShortExport> Exports;
   for (Export &E1 : Config->Exports) {
     COFFShortExport E2;
-    E2.Name = E1.Name;
+    // Use SymbolName, which will have any stdcall or fastcall qualifiers.
+    E2.Name = E1.SymbolName;
     E2.ExtName = E1.ExtName;
     E2.Ordinal = E1.Ordinal;
     E2.Noname = E1.Noname;

llvm-svn: 304573
2017-06-02 17:53:06 +00:00
Reid Kleckner d249e4a188 Revert "COFF: migrate def parser from LLD to LLVM"
This reverts commits r303490, r303491, r303493, and r303494.

This caused http://crbug.com/728726. Essentially, exporting stdcall
functions doesn't appear to work after this change. Reduced test case
soon.

llvm-svn: 304561
2017-06-02 16:26:24 +00:00
Martell Malone 1e39e5e964 COFF: migrate def parser from LLD to LLVM [2/2]
This is split up into two commits.
This commit removes the DEF parser from LLD
See the previous commit for the creation in LLVM.

Reviewers: ruiu

Differential Revision: https://reviews.llvm.org/D32689

llvm-svn: 303491
2017-05-20 19:56:44 +00:00
Rui Ueyama a674943211 Set IMAGE_DLL_CHARACTERISTICS_NO_BIND.
Our output is not compatible with the Binding feature, so make it
explicit that.

Differential Revision: https://reviews.llvm.org/D33336

llvm-svn: 303378
2017-05-18 20:26:58 +00:00
Rui Ueyama 01f93335a0 Use make<> everywhere in COFF to make it consistent with ELF.
We've been using make<> to allocate new objects in ELF. We have
the same function in COFF, but we didn't use it widely due to
negligence. This patch uses the function in COFF to close the gap
between ELF and COFF.

llvm-svn: 303357
2017-05-18 17:03:49 +00:00
Zachary Turner 8a7508970a [COFF] Fix interaction between /DEBUG and /PDB
When /DEBUG is not specified, /PDB should be ignored.  When
/DEBUG is specified, a PDB should be output regardless of
whether or not /PDB is specified.  /PDB just overrides the
default name.

This patch implements this behavior, and adds some tests, while
also removing a dead option /DEBUGPDB which was unused in any
code.

Differential Revision: https://reviews.llvm.org/D33302

llvm-svn: 303352
2017-05-18 15:15:10 +00:00
Peter Collingbourne c6f07c423d Move lib/LibDriver -> lib/ToolDrivers/llvm-lib. NFCI.
This reorganisation prevents us from cluttering up the top-level lib directory
with more driver libraries such as llvm-dlltool (see D29892).

llvm-svn: 302995
2017-05-13 22:06:46 +00:00
Bob Haarman 4110816253 [coff] for /msvclto, pass archive members with prevailing symbols first
Summary: When using /msvclto, lld and MSVC's linker both do their own symbol resolution. This can cause them to select different archive members, which can result in undefined references. This change avoids that situation by extracting archive members that are selected by lld and passing those to link.exe before any archives, so that MSVC's uses those objects for symbol resolution instead of different archive members.

Reviewers: pcc, rnk, ruiu

Reviewed By: pcc

Subscribers: llvm-commits, mehdi_amini

Differential Revision: https://reviews.llvm.org/D32317

llvm-svn: 301045
2017-04-21 21:38:01 +00:00
Bob Haarman 630d0c0f44 [coff] use newlines instead of spaces as separators in msvclto response file
Summary:
Fixes PR32689: /msvclto creates response files with lines
that are too long for msvc's linker (LNK1170).

Reviewers: hans, rnk, ruiu

Subscribers: llvm-commits, mehdi_amini

Differential Revision: https://reviews.llvm.org/D32185

llvm-svn: 300612
2017-04-18 22:00:29 +00:00
Richard Smith a13714ea5f Update to match LLVM r300135.
llvm-svn: 300141
2017-04-12 23:51:20 +00:00