Commit Graph

1341 Commits

Author SHA1 Message Date
Reid Kleckner 91a6bfed61 [COFF] Assign unique identifiers to ObjFiles from LTO
Use the unique filenames that are used when /lldsavetemps is passed.
After this change, module names for LTO blobs in PDBs will be unique.
Visual Studio and probably other debuggers expect module names to be
unique.

Revert some changes from 1e0b158db (2017) that are no longer necessary
after removing MSVC LTO support.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D78221
2020-04-17 17:15:12 -07:00
Martin Storsjö 12c9e2f111 [LLD] [COFF] Fix alignment of thunks for ARM/ARM64
The alignment of ARM64 range extension thunks was fixed in
7c81649219, but ARM range extension thunks, and import
and delay import thunks also need aligning (like all code on ARM
platforms).

I'm adding a test for alignment of ARM64 import thunks - not
specifically adding tests for misalignment of all of them though.

Differential Revision: https://reviews.llvm.org/D77796
2020-04-13 23:27:15 +03:00
Eric Astor a39b14f0b4 [ms] Add new /PDBSTREAM option to lld-link allowing injection of streams into PDB files.
Summary:
/PDBSTREAM:<name>=<file> adds the contents of <file> to stream <name> in the resulting PDB.

This allows native uses with workflows that (for example) add srcsrv streams to PDB files to provide a location for the build's source files.

Results should be equivalent to linking with lld-link, then running Microsoft's pdbstr tool with the command line:
pdbstr.exe -w -p:<PDB LOCATION> -s:<name> -i:<file>
except in cases where the named stream overlaps with a default named stream, such as "/names". In those cases, the added stream will be overridden, making the /pdbstream option a no-op.

Reviewers: thakis, rnk

Reviewed By: thakis

Differential Revision: https://reviews.llvm.org/D77310
2020-04-07 16:19:38 -04:00
Benjamin Kramer 02cb21df3f Make helpers static. NFC. 2020-04-03 12:48:25 +02:00
Fangrui Song eb4663d8c6 [lld][COFF][ELF][WebAssembly] Replace --[no-]threads /threads[:no] with --threads={1,2,...} /threads:{1,2,...}
--no-threads is a name copied from gold.
gold has --no-thread, --thread-count and several other --thread-count-*.

There are needs to customize the number of threads (running several lld
processes concurrently or customizing the number of LTO threads).
Having a single --threads=N is a straightforward replacement of gold's
--no-threads + --thread-count.

--no-threads is used rarely. So just delete --no-threads instead of
keeping it for compatibility for a while.

If --threads= is specified (ELF,wasm; COFF /threads: is similar),
--thinlto-jobs= defaults to --threads=,
otherwise all available hardware threads are used.

There is currently no way to override a --threads={1,2,...}. It is still
a debate whether we should use --threads=all.

Reviewed By: rnk, aganea

Differential Revision: https://reviews.llvm.org/D76885
2020-03-31 08:46:12 -07:00
Nico Weber 20eb719f99 lld: Reduce number of references to undefined printed from 10 to 3.
As of a while ago, lld groups all undefined references to a single
symbol in a single diagnostic. Back then, I made it so that we
print up to 10 references to each undefined symbol.

Having used this for a while, I never wished there were more
references, but I sometimes found that this can print a lot of
output. lld prints up to 10 diagnostics by default, and if
each has 10 references (which I've seen in practice), and each
undefined symbol produces 2 (possibly very long) lines of output,
that's over 200 lines of error output.

Let's try it with just 3 references for a while and see how
that feels in practice.

Differential Revision: https://reviews.llvm.org/D77017
2020-03-30 14:31:32 -04:00
Benjamin Kramer b578f130a7 [COFF] Stabilize sort
Found by llvm::sort's expensive checks.
2020-03-28 21:38:50 +01:00
Reid Kleckner c579a5b1d9 [COFF] Don't treat DWARF sections as GC roots
DWARF sections are typically live and not COMDAT, so they would be
treated as GC roots. Enabling DWARF would essentially keep all code with
debug info alive, preventing any section GC.

Fixes PR45273

Reviewed By: mstorsjo, MaskRay

Differential Revision: https://reviews.llvm.org/D76935
2020-03-27 12:37:43 -07:00
Alexandre Ganea 09158252f7 [ThinLTO] Allow usage of all hardware threads in the system
Before this patch, it wasn't possible to extend the ThinLTO threads to all SMT/CMT threads in the system. Only one thread per core was allowed, instructed by usage of llvm::heavyweight_hardware_concurrency() in the ThinLTO code. Any number passed to the LLD flag /opt:lldltojobs=..., or any other ThinLTO-specific flag, was previously interpreted in the context of llvm::heavyweight_hardware_concurrency(), which means SMT disabled.

One can now say in LLD:
/opt:lldltojobs=0 -- Use one std::thread / hardware core in the system (no SMT). Default value if flag not specified.
/opt:lldltojobs=N -- Limit usage to N threads, regardless of usage of heavyweight_hardware_concurrency().
/opt:lldltojobs=all -- Use all hardware threads in the system. Equivalent to /opt:lldltojobs=$(nproc) on Linux and /opt:lldltojobs=%NUMBER_OF_PROCESSORS% on Windows. When an affinity mask is set for the process, threads will be created only for the cores selected by the mask.

When N > number-of-hardware-threads-in-the-system, the threads in the thread pool will be dispatched equally on all CPU sockets (tested only on Windows).
When N <= number-of-hardware-threads-on-a-CPU-socket, the threads will remain on the CPU socket where the process started (only on Windows).

Differential Revision: https://reviews.llvm.org/D75153
2020-03-27 10:20:58 -04:00
Sylvain Audi b91905a263 [lld-link] Support /map option, matching link.exe 's /map output format
Added support for /map and /map:[filepath].
The output was derived from Microsoft's Link.exe output when using that same option.
Note that /MAPINFO support was not added.

The previous implementation of MapFile.cpp/.h was meant for /lldmap, and was renamed to LLDMapFile.cpp/.h
MapFile.cpp/.h is now for /MAP
However, a small fix was added to lldmap, replacing a std::sort with std::stable_sort to enforce reproducibility.

Differential Revision: https://reviews.llvm.org/D70557
2020-03-24 09:48:00 -04:00
Vitaly Buka 8620bb9534 [lld] Fix "loop variable creates a copy" warning 2020-03-16 22:52:49 -07:00
Rui Ueyama a2923b2a1e Implement CET Shadow Stack (Intel Controlflow Enforcement Technology) support on Windows
Patch by Petr Penzin.

Windows support for CET is limited to shadow stack, which is enabled
by setting a PE bit in the linker.

Docs:

MSVC linker flag:
https://docs.microsoft.com/en-us/cpp/build/reference/cetcompat?view=vs-2019

IMAGE_DLLCHARACTERISTICS_EX_CET_COMPAT PE bit:
https://docs.microsoft.com/en-us/windows/win32/debug/pe-format#extended-dll-characteristics

Differential Revision: https://reviews.llvm.org/D70606
2020-03-16 17:51:32 +09:00
evgeny 497c110e87 [lld][ELF][COFF] Fix archived bitcode files naming
Differential revision: https://reviews.llvm.org/D75422
2020-03-04 12:46:31 +03:00
Reid Kleckner 8a310f40d0 Remove namespace lld { namespace coff { from COFF LLD cpp files
Instead, use `using namespace lld(::coff)`, and fully qualify the names
of free functions where they are defined in cpp files.

This effectively reverts d79c3be618 to follow the new style guide added
in 236fcbc21a.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D74882
2020-02-25 17:30:53 -08:00
Jonas Devlieghere 3e24242a7d [lld] Replace SmallStr.str().str() with std::string conversion operator.
Use the std::string conversion operator introduced in
d7049213d0.
2020-01-29 21:30:21 -08:00
Benjamin Kramer adcd026838 Make llvm::StringRef to std::string conversions explicit.
This is how it should've been and brings it more in line with
std::string_view. There should be no functional change here.

This is mostly mechanical from a custom clang-tidy check, with a lot of
manual fixups. It uncovers a lot of minor inefficiencies.

This doesn't actually modify StringRef yet, I'll do that in a follow-up.
2020-01-28 23:25:25 +01:00
Reid Kleckner e5caa156b4 [PDB] Simplify API for making section map, NFC
Prevents API misuse described in PR44495
2020-01-23 12:15:21 -08:00
Martin Storsjö e6b0ce70bd [LLD] [COFF] Silence a GCC warning about an unused variable. NFC. 2020-01-23 13:23:56 +02:00
Markus Böck 9dbc1ab232 [LLD][COFF] Enable linking of __declspec(selectany) symbols from Clang and GCC
When annotating a symbol with __declspec(selectany), Clang assigns it
comdat 2 while GCC assigns it comdat 3. This patch enables two object
files that contain a __declspec(selectany) symbol, one created by gcc
and the other by clang, to be linked together instead of issuing a
duplicate symbol error.

Differential Revision: https://reviews.llvm.org/D73139
2020-01-23 10:55:27 +02:00
Reid Kleckner 8045a8a7f1 [COFF] Warn that LLD does not support /PDBSTRIPPED:
Doesn't really fix PR44491, but it avoids treating it as an input.
2020-01-15 15:11:19 -08:00
Tom Tan 7c81649219 [COFF] Align ARM64 range extension thunks at instruction boundary
RangeExtensionThunkARM64 is created for out-of-range branches on Windows ARM64
because branch instructions has limited bits to encode target address.
Currently, RangeExtensionThunkARM64 is appended to its referencing COFF section
from object file at link time without any alignment requirement, so if size of
the preceding COFF section is not aligned to instruction boundary (4 bytes),
RangeExtensionThunkARM64 will emit thunk instructions at unaligned address
which is never a valid branch target on ARM64, and usually triggers invalid
instruction exception when branching to it.

This PR fixes it by requiring such thunks to align at 4 bytes.

Differential revision: https://reviews.llvm.org/D72473
2020-01-10 19:03:17 -08:00
Wei Mi 21a4710c67 [ThinLTO] Pass CodeGenOpts like UnrollLoops/VectorizeLoop/VectorizeSLP
down to pass builder in ltobackend.

Currently CodeGenOpts like UnrollLoops/VectorizeLoop/VectorizeSLP in clang
are not passed down to pass builder in ltobackend when new pass manager is
used. This is inconsistent with the behavior when new pass manager is used
and thinlto is not used. Such inconsistency causes slp vectorization pass
not being enabled in ltobackend for O3 + thinlto right now. This patch
fixes that.

Differential Revision: https://reviews.llvm.org/D72386
2020-01-09 21:13:11 -08:00
Martin Storsjö 78ce19b7e1 [LLD] [COFF] Fix post-commit suggestions for absolute symbol equality
Differential Revision: https://reviews.llvm.org/D72252
2020-01-08 22:10:05 +02:00
Martin Storsjö 1737cc750c [LLD] [COFF] Don't error out on duplicate absolute symbols with the same value
Both MS link.exe and GNU ld.bfd handle it this way; one can have
multiple object files defining the same absolute symbols, as long
as it defines it to the same value. But if there are multiple absolute
symbols with differing values, it is treated as an error.

Differential Revision: https://reviews.llvm.org/D71981
2020-01-04 12:29:33 +02:00
Reid Kleckner 783db78835 [PDB] Print the most redundant type record indices with /summary
Summary:
I used this information to motivate splitting up the Intrinsic::ID enum
(5d986953c8) and adding a key method to
clang::Sema (586f65d31f) which saved a
fair amount of object file size.

Example output for clang.pdb:

  Top 10 types responsible for the most TPI input bytes:
         index     total bytes   count     size
        0x3890:      8,671,220 = 1,805 *  4,804
       0xE13BE:      5,634,720 =   252 * 22,360
       0x6874C:      5,181,600 =   408 * 12,700
        0x2A1F:      4,520,528 = 1,574 *  2,872
       0x64BFF:      4,024,020 =   469 *  8,580
        0x1123:      4,012,020 = 2,157 *  1,860
        0x6952:      3,753,792 =   912 *  4,116
        0xC16F:      3,630,888 =   633 *  5,736
        0x69DD:      3,601,160 =   985 *  3,656
        0x678D:      3,577,904 =   319 * 11,216

In this case, we can see that record 0x3890 is responsible for ~8MB of
total object file size for objects in clang.

The user can then use llvm-pdbutil to find out what the record is:

  $ llvm-pdbutil dump -types -type-index 0x3890
                       Types (TPI Stream)
  ============================================================
    Showing 1 records.
       0x3890 | LF_FIELDLIST [size = 4804]
                - LF_STMEMBER [name = `WORDTYPE_MAX`, type = 0x1001, attrs = public]
                - LF_MEMBER [name = `U`, Type = 0x37F0, offset = 0, attrs = private]
                - LF_MEMBER [name = `BitWidth`, Type = 0x0075 (unsigned), offset = 8, attrs = private]
                - LF_METHOD [name = `APInt`, # overloads = 8, overload list = 0x3805]
  ...

In this case, we can see that these are members of the APInt class,
which is emitted in 1805 object files.

The next largest type is ASTContext:

  $ llvm-pdbutil dump -types -type-index 0xE13BE bin/clang.pdb
      0xE13BE | LF_FIELDLIST [size = 22360]
                - LF_BCLASS
                  type = 0x653EA, offset = 0, attrs = public
                - LF_MEMBER [name = `Types`, Type = 0x653EB, offset = 8, attrs = private]
                - LF_MEMBER [name = `ExtQualNodes`, Type = 0x653EC, offset = 24, attrs = private]
                - LF_MEMBER [name = `ComplexTypes`, Type = 0x653ED, offset = 48, attrs = private]
                - LF_MEMBER [name = `PointerTypes`, Type = 0x653EE, offset = 72, attrs = private]
  ...

ASTContext only appears 252 times, but the list of members is long, and
must be repeated everywhere it is used.

This was the output before I split Intrinsic::ID:

  Top 10 types responsible for the most TPI input:
        0x686C:     69,823,920 = 1,070 * 65,256
        0x686D:     69,819,640 = 1,070 * 65,252
        0x686E:     69,819,640 = 1,070 * 65,252
        0x686B:     16,371,000 = 1,070 * 15,300
        ...

These records were all lists of intrinsic enums.

Reviewers: MaskRay, ruiu

Subscribers: mgrang, zturner, thakis, hans, akhuang, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71437
2020-01-02 16:10:36 -08:00
Fangrui Song 681b1be774 [lld] Fix -Wrange-loop-analysis warnings
One instance looks like a false positive:

lld/ELF/Relocations.cpp:1622:14: note: use reference type 'const std::pair<ThunkSection *, uint32_t> &' (aka 'cons
t pair<lld:🧝:ThunkSection *, unsigned int> &') to prevent copying
        for (const std::pair<ThunkSection *, uint32_t> ts : isd->thunkSections)

It is not changed in this commit.
2020-01-01 15:41:20 -08:00
David Blaikie 22f34c7f34 lld: Remove explicit copy ops from AssociatedIterator, relying on implicit operators 2019-12-27 17:27:20 -08:00
Martin Storsjö 29d8c27c65 [LLD] [COFF] Fix reporting duplicate errors for absolute symbols
Previously this caused crashes in the reportDuplicate method.

A DefinedAbsolute doesn't have any InputFile attached to it, so we
can't report the file for the original symbol.

We could add an InputFile argument to SymbolTable::addAbsolute
only for the sake of error reporting, but even then it'd be assymetrical,
only pointing out the file containing the new conflicting definition,
not the original one.

Differential Revision: https://reviews.llvm.org/D71679
2019-12-19 12:14:08 +02:00
Nemanja Ivanovic 4d5c8caf9b [LLD] Add a default copy constructor to avoid warnings
This should fix the failure on the PPC64LE LLD bot.
2019-11-25 14:09:16 -06:00
James Y Knight d3fec7fb45 LLD: Don't use the stderrOS stream in link before it's reassigned.
Remove the lld::enableColors function, as it just obscures which
stream it's affecting, and replace with explicit calls to the stream's
enable_colors.

Also, assign the stderrOS and stdoutOS globals first in link function,
just to ensure nothing might use them.

(Either change individually fixes the issue of using the old
stream, but both together seems best.)

Follow-up to b11386f9be.

Differential Revision: https://reviews.llvm.org/D70492
2019-11-21 10:55:03 -05:00
Rui Ueyama 47feae5dd6 Use lld::make<T> to make TpiSource objects
In lld we rarely use std::unique_ptr but instead allocate new instances
using lld::make<T>() so that they are deallocated at the end of linking.
This patch changes existing code so that that follows the convention.

Differential Revision: https://reviews.llvm.org/D70420
2019-11-20 13:14:44 +09:00
Rui Ueyama b11386f9be Make it possible to redirect not only errs() but also outs()
This change is for those who use lld as a library. Context:
https://reviews.llvm.org/D70287

This patch adds a new parmeter to lld::*::link() so that we can pass
an raw_ostream object representing stdout. Previously, lld::*::link()
took only an stderr object.

Justification for making stdoutOS and stderrOS mandatory: I wanted to
make link() functions to take stdout and stderr in that order.
However, if we change the function signature from

  bool link(ArrayRef<const char *> args, bool canExitEarly,
            raw_ostream &stderrOS = llvm::errs());

to

  bool link(ArrayRef<const char *> args, bool canExitEarly,
            raw_ostream &stdoutOS = llvm::outs(),
            raw_ostream &stderrOS = llvm::errs());

, then the meaning of existing code that passes stderrOS silently
changes (stderrOS would be interpreted as stdoutOS). So, I chose to
make existing code not to compile, so that developers can fix their
code.

Differential Revision: https://reviews.llvm.org/D70292
2019-11-18 11:18:06 +09:00
Reid Kleckner ce0f3ee5e4 [COFF] Don't error if the only inputs are from /wholearchive:
Fixes PR43744

Differential Revision: https://reviews.llvm.org/D69968
2019-11-15 16:09:07 -08:00
Reid Kleckner 4c1a1d3cf9 Add missing includes needed to prune LLVMContext.h include, NFC
These are a pre-requisite to removing #include "llvm/Support/Options.h"
from LLVMContext.h: https://reviews.llvm.org/D70280
2019-11-14 15:23:15 -08:00
Reid Kleckner de3fb1ec05 [COFF] Avoid CodeView include in header
Most LLD/COFF files don't care about CodeView. Avoid using CodeView
types in InputFiles.h.
2019-11-14 14:27:48 -08:00
Reid Kleckner adfad4d7c8 Forward declare the DWARFCache to avoid including LLVM DWARF details
LLD's DWARF.h header leaks a lot of LLVM DWARF includes that LLD doesn't
need. For Chunks.cpp, I see a compile time decrease of 3.1s to 2.7s.
2019-11-14 14:17:49 -08:00
Reid Kleckner f24c3352c9 [COFF] Don't include llvm/LTO/LTO.h in a header
LLVM's LTO header includes all of llvm/IR, which most of the COFF linker
doesn't need.
2019-11-14 13:47:18 -08:00
Rui Ueyama 000ff301e7 Warn on /align if used without /driver
/align is not supposed to be used without /driver, so it makes sense
to warn if only /align is passed. MSVC link.exe warns on this too.

Differential Revision: https://reviews.llvm.org/D70163
2019-11-14 13:13:07 +09:00
Rui Ueyama f95ed69641 Implement /driver, /driver:wdm and /driver:uponly
This patch implements /driver, /driver:wdm and /driver:uponly as
described in
https://docs.microsoft.com/en-us/cpp/build/reference/driver-windows-nt-kernel-mode-driver?view=vs-2019.

Differential Revision: https://reviews.llvm.org/D70162
2019-11-14 13:07:56 +09:00
Martin Storsjö 38bc9559ba [LLD] [COFF] Fix automatically importing data symbols from DLLs with LTO
This broke in 51dcb292cc, "[lld-link] diagnose undefined symbols
before LTO when possible" (very soon after the 9.0 branch, so
luckily the 9.0 release is unaffected).

The code for loading objects we believe might be needed for autoimport
(loadMinGWAutomaticImports()) does run before the new
reportUnresolvable() function, but it had a condition to only operate
on symbols from regular object files. This condition came from
resolveRemainingUndefines(), but as loadMinGWAutomaticImports() now
has to operate before the LTO, it has to operate on undefineds from
LTO objects as well.

Differential Revision: https://reviews.llvm.org/D70166
2019-11-13 22:48:36 +02:00
Reid Kleckner deaf121b65 Warn when an output section name is longer than 8 characters
Recent versions of Microsoft's dumpbin tool cannot handle such PE files.
LLVM tools and GNU tools can, and use this to encode long section names
like ".debug_info", which is commonly used for DWARF. Don't do this in
mingw mode or when -debug:dwarf is passed, since the user probably wants
long section names for DWARF sections.

PR43754

Reviewers: ruiu, mstorsjo

Differential Revision: https://reviews.llvm.org/D69594
2019-11-01 12:59:13 -07:00
Nico Weber b911d2db5d lld/COFF: Simplify getOutputPath() using sys::path functions.
Also mention "basename" and "dirname" in Path.h since I tried
to find these functions by looking for these strings. It might
help others find them faster if the comments contain these strings.

No behavior change.

Differential Revision: https://reviews.llvm.org/D69458
2019-10-28 10:38:32 -04:00
Martin Storsjo 150a9ad3ff [LLD] [COFF] Fix use of uninitialized memory since SVN r375390
llvm-svn: 375400
2019-10-21 09:35:34 +00:00
Martin Storsjo 65b1c497d2 [LLD] [COFF] Use the local dwarf code instead of Symbolizer for resolving code locations. NFC.
As we now have code that parses the dwarf info for variable locations,
we can use that instead of relying on the higher level Symbolizer library,
reducing the previous two different dwarf codepaths into one.

Differential Revision: https://reviews.llvm.org/D69198

llvm-svn: 375391
2019-10-21 08:01:59 +00:00
Martin Storsjo 908b780952 [LLD] Move duplicated dwarf parsing code to the Common library. NFC.
Differential Revision: https://reviews.llvm.org/D69197

llvm-svn: 375390
2019-10-21 08:01:52 +00:00
Michael Liao 92fea8bb8d [lld][coff] Add missing dependency to fix build.
llvm-svn: 375238
2019-10-18 14:31:58 +00:00
Martin Storsjo b38f577c01 [LLD] [COFF] Try to report source locations for duplicate symbols
This fixes the second part of PR42407.

For files with dwarf debug info, it manually loads and iterates
.debug_info to find the declared location of variables, to allow
reporting them. (This matches the corresponding code in the ELF
linker.)

For functions, it uses the existing getFileLineDwarf which uses
LLVMSymbolizer for translating addresses to file lines.

In object files with codeview debug info, only the source location
of duplicate functions is printed. (And even there, only for the
first input file. The getFileLineCodeView function requires the
object file to be fully loaded and initialized to properly resolve
source locations, but duplicate symbols are reported at a stage when
the second object file isn't fully loaded yet.)

Differential Revision: https://reviews.llvm.org/D68975

llvm-svn: 375218
2019-10-18 10:43:15 +00:00
Martin Storsjo e0916f4fbe [LLD] [COFF] Update a leftover comment after SVN r374869. NFC.
llvm-svn: 374874
2019-10-15 09:46:33 +00:00
Martin Storsjo cd8759c3c2 [LLD] [COFF] Fix -Wmissing-field-initializers warnings. NFC.
llvm-svn: 374873
2019-10-15 09:33:14 +00:00
Martin Storsjo 9318c94ebb [LLD] [COFF] Wrap file location pair<StringRef,int> in Optional<>. NFC.
This makes use of it slightly clearer, and makes it match the
same construct in the lld ELF linker.

Differential Revision: https://reviews.llvm.org/D68935

llvm-svn: 374869
2019-10-15 09:18:18 +00:00