Commit Graph

29 Commits

Author SHA1 Message Date
Nico Weber cc2d4dc3e0 Reland "Try to unbreak Win build differently after 973519826edb76""
Build should be fixed by
https://github.com/llvm/llvm-project/commit/9d22754389

This reverts commit df052e1732.

Differential Revision: https://reviews.llvm.org/D109181
2021-09-02 16:19:58 -07:00
Geoffrey Martin-Noble df052e1732 Revert "Try to unbreak Win build differently after 973519826edb76"
Breaks the build and failed pre-merge checks:
https://buildkite.com/llvm-project/premerge-checks/builds/54930#07373971-3d37-49cf-9def-22c0d724ee23

> llvm-project/lld/wasm/Writer.cpp:521:16: error: non-const lvalue reference to
>  type 'llvm::StringRef' cannot bind to a temporary of type 'llvm::StringRef'
>    for (auto &feature : used.keys()) {

This reverts commit 5881dcff7e.
2021-09-02 12:05:33 -07:00
Nico Weber 5881dcff7e Try to unbreak Win build differently after 973519826e
Looks like the MS STL wants StringMapKeyIterator::operator*() to be const.
Return the result by copy instead of reference to do that.
Assigning to a hash map key iterator doesn't make sense anyways.

Also reverts 123f811fe5 which is now hopefully no longer needed.

Differential Revision: https://reviews.llvm.org/D109167
2021-09-02 14:45:56 -04:00
Nico Weber 123f811fe5 Try to unbreak Win build after 973519826e
Apparently some versions of the MS STL don't like constructing a
vector from a StringMapKeyIterator<>: http://45.33.8.238/win/44999/step_4.txt
It builds fine with the MS STL on my Windows box, so just sidestep the issue.

Full error for posterity:

    VC\Tools\MSVC\14.14.26428\include\xmemory(218,75):
      error: indirection requires pointer operand ('const llvm::StringMapKeyIterator<llvm::StringRef>' invalid)
          _Uses_default_construct_t<_Alloc, decltype(_Unfancy(_UDest)), decltype(*_UFirst)>())));
    VC\Tools\MSVC\14.14.26428\include\vector(1922,11):
      note: in instantiation of function template specialization 'std::_Uninitialized_copy<...>' requested here
                    return (_Uninitialized_copy(_First, _Last, _Dest, this->_Getal()));
    VC\Tools\MSVC\14.14.26428\include\vector(757,22):
      note: in instantiation of function template specialization
            'std::vector<llvm::StringRef>::_Ucopy<llvm::StringMapKeyIterator<llvm::StringRef>>' requested here
                            this->_Mylast() = _Ucopy(_First, _Last, this->_Myfirst());
    VC\Tools\MSVC\14.14.26428\include\vector(772,3):
      note: in instantiation of function template specialization
            'std::vector<llvm::StringRef>::_Range_construct_or_tidy<llvm::StringMapKeyIterator<llvm::StringRef>>' requested here
                    _Range_construct_or_tidy(_Unchecked(_First), _Unchecked(_Last), _Iter_cat_t<_Iter>{});
    ../../clang/lib/Driver/ToolChains/Arch/X86.cpp(62,30):
      note: in instantiation of function template specialization
            'std::vector<llvm::StringRef>::vector<llvm::StringMapKeyIterator<llvm::StringRef>, void>' requested here
          std::vector<StringRef> ValidArchs{ArchMap.keys().begin(),
2021-09-02 12:06:53 -04:00
Nico Weber 973519826e [clang-cl] Emit nicer warning on unknown /arch: arguments
Now prints the list of known archs. This requires plumbing a Driver
arg through a few functions.

Also add two more convenience insert() overlods to StringMap.

Differential Revision: https://reviews.llvm.org/D109105
2021-09-02 10:37:32 -04:00
Tianqing Wang d8faf03807 [X86] Add -mgeneral-regs-only support.
Reviewed By: pengfei

Differential Revision: https://reviews.llvm.org/D103943
2021-06-29 16:02:51 +08:00
Brad Smith cd5ab56bc4 Change the default target CPU for OpenBSD/i386 to i586 2020-08-08 13:49:45 -04:00
Craig Topper 4df38a5589 [X86] Optimize out a few extra strlen calls in getX86TargetCPU. NFCI
We had a conversion from const char * to StringRef and const char *
to std::string conversion. These both do their own
strlen call if the compiler doens't figure out how to share them.
By adding the temporary StringRef we can convert it to std::string
instead.

The other case is to use a StringSwitch<StringRef> instead of
StringSwitch<const char *> since the output values of the switch
are string literals. This allows the length to be computed at
compile time. Otherwise we have to convert from const char *
to std::string after the StringSwitch.
2020-08-06 13:18:15 -07:00
Craig Topper e1cad4234c [X86] Make getX86TargetCPU return std::string instead of const char *. Remove call to MakeArgString. NFCI
I believe this function used to be called directly from X86
specific code and was used to immediately create -target-cpu
command line. A later refactoring changed it to to be called from
a generic getCPU function that returns std::string. So on some
paths we created a string using MakeArgString converted that to
std::string then called MakeArgString again from that.

Instead just return std::string directly like the other targets.
2020-08-06 13:18:15 -07:00
Dimitry Andric 02cfa7530d Bump the default target CPU for i386-freebsd to i686
Summary:
Similar to what we have done downstream, some time ago:
https://svnweb.freebsd.org/changeset/base/353936

This followed some discussions on the freebsd-arch mailing lists, and
most people agreed that it was a better default, and also it worked
around several issues where clang generated libcalls to 64 bit atomic
primitives, instead of using cmpxchg8b.

Reviewers: emaste, brooks, rsmith

Reviewed By: emaste

Subscribers: arichardson, krytarowski, jfb, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D83645
2020-07-12 23:45:22 +02:00
Zola Bridges 9d9e499840 [x86][seses] Add clang flag; Use lvi-cfi with seses
This patch creates a clang flag to enable SESES. This flag also ensures that
lvi-cfi is on when using seses via clang.

SESES should use lvi-cfi to mitigate returns and indirect branches.

The flag to enable the SESES functionality only without lvi-cfi is now
-x86-seses-enable-without-lvi-cfi to warn users part of the mitigation is not
enabled if they use this flag. This is useful in case folks want to see the
cost of SESES separate from the LVI-CFI.

Reviewed By: sconstab

Differential Revision: https://reviews.llvm.org/D79910
2020-07-07 13:20:13 -07:00
Scott Constable e97a3e5d9d [X86] Add a Pass that builds a Condensed CFG for Load Value Injection (LVI) Gadgets
Adds a new data structure, ImmutableGraph, and uses RDF to find LVI gadgets and add them to a MachineGadgetGraph.

More specifically, a new X86 machine pass finds Load Value Injection (LVI) gadgets consisting of a load from memory (i.e., SOURCE), and any operation that may transmit the value loaded from memory over a covert channel, or use the value loaded from memory to determine a branch/call target (i.e., SINK).

Also adds a new target feature to X86: +lvi-load-hardening

The feature can be added via the clang CLI using -mlvi-hardening.

Differential Revision: https://reviews.llvm.org/D75936
2020-05-11 13:08:35 -07:00
Craig Topper 1d42c0db9a Revert "[X86] Add a Pass that builds a Condensed CFG for Load Value Injection (LVI) Gadgets"
This reverts commit c74dd640fd.

Reverting to address coding standard issues raised in post-commit
review.
2020-04-03 16:56:08 -07:00
Scott Constable c74dd640fd [X86] Add a Pass that builds a Condensed CFG for Load Value Injection (LVI) Gadgets
Adds a new data structure, ImmutableGraph, and uses RDF to find LVI gadgets and add them to a MachineGadgetGraph.

More specifically, a new X86 machine pass finds Load Value Injection (LVI) gadgets consisting of a load from memory (i.e., SOURCE), and any operation that may transmit the value loaded from memory over a covert channel, or use the value loaded from memory to determine a branch/call target (i.e., SINK).

Also adds a new target feature to X86: +lvi-load-hardening

The feature can be added via the clang CLI using -mlvi-hardening.

Differential Revision: https://reviews.llvm.org/D75936
2020-04-03 13:02:04 -07:00
Scott Constable 5b519cf1fc [X86] Add Indirect Thunk Support to X86 to mitigate Load Value Injection (LVI)
This pass replaces each indirect call/jump with a direct call to a thunk that looks like:

lfence
jmpq *%r11

This ensures that if the value in register %r11 was loaded from memory, then
the value in %r11 is (architecturally) correct prior to the jump.
Also adds a new target feature to X86: +lvi-cfi
("cfi" meaning control-flow integrity)
The feature can be added via clang CLI using -mlvi-cfi.

This is an alternate implementation to https://reviews.llvm.org/D75934 That merges the thunk insertion functionality with the existing X86 retpoline code.

Differential Revision: https://reviews.llvm.org/D76812
2020-04-03 00:34:39 -07:00
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
Jim Lin ab1bcda851 [NFC] Use isX86() instead of getArch()
Summary: This is a clean up for https://reviews.llvm.org/D72247.

Reviewers: MaskRay, craig.topper, jhenderson

Reviewed By: MaskRay

Subscribers: hiraditya, rupprecht, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D72320
2020-01-07 17:35:44 +08:00
Reid Kleckner 90c64a3456 Move endian constant from Host.h to SwapByteOrder.h, prune include
Works on this dependency chain:
  ArrayRef.h ->
  Hashing.h -> --CUT--
  Host.h ->
  StringMap.h / StringRef.h

ArrayRef is very popular, but Host.h is rarely needed. Move the
IsBigEndianHost constant to SwapByteOrder.h. Clients of that header are
more likely to need it.

llvm-svn: 375316
2019-10-19 00:48:11 +00:00
George Burgess IV fdeed837ed Fix a typo in target features
There was a slight typo in r364352 that ended up causing our backend to
complain on some x86 Android builds. This CL fixes that.

Differential Revision: https://reviews.llvm.org/D64781

llvm-svn: 366276
2019-07-16 22:32:17 +00:00
Saleem Abdulrasool c32d307a49 android: enable double-word CAS on x64
The android target assumes that for the x86_64 target, the CPU supports SSE4.2
and popcnt. This implies that the CPU is Nehalem or newer. This should be
sufficiently new to provide the double word compare and exchange instruction.
This allows us to directly lower `__sync_val_compare_and_swap_16` to a `cmpxchg16b`.
It appears that the libatomic in android's NDK does not provide the
implementation for lowering calls to the library function.

llvm-svn: 364352
2019-06-25 21:43:34 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
Francis Visoiu Mistrih d18f17e587 [Driver] Don't override '-march' when using '-arch x86_64h'
On Darwin, using '-arch x86_64h' would always override the option passed
through '-march'.

This patch allows users to use '-march' with x86_64h, while keeping the
default to 'core-avx2'

Differential Revision: https://reviews.llvm.org/D55775

llvm-svn: 349381
2018-12-17 19:29:27 +00:00
Chandler Carruth 664aa868f5 [x86/SLH] Add a real Clang flag and LLVM IR attribute for Speculative
Load Hardening.

Wires up the existing pass to work with a proper IR attribute rather
than just a hidden/internal flag. The internal flag continues to work
for now, but I'll likely remove it soon.

Most of the churn here is adding the IR attribute. I talked about this
Kristof Beyls and he seemed at least initially OK with this direction.
The idea of using a full attribute here is that we *do* expect at least
some forms of this for other architectures. There isn't anything
*inherently* x86-specific about this technique, just that we only have
an implementation for x86 at the moment.

While we could potentially expose this as a Clang-level attribute as
well, that seems like a good question to defer for the moment as it
isn't 100% clear whether that or some other programmer interface (or
both?) would be best. We'll defer the programmer interface side of this
for now, but at least get to the point where the feature can be enabled
without relying on implementation details.

This also allows us to do something that was really hard before: we can
enable *just* the indirect call retpolines when using SLH. For x86, we
don't have any other way to mitigate indirect calls. Other architectures
may take a different approach of course, and none of this is surfaced to
user-level flags.

Differential Revision: https://reviews.llvm.org/D51157

llvm-svn: 341363
2018-09-04 12:38:00 +00:00
Chandler Carruth ae0cafece8 [x86/retpoline] Split the LLVM concept of retpolines into separate
subtarget features for indirect calls and indirect branches.

This is in preparation for enabling *only* the call retpolines when
using speculative load hardening.

I've continued to use subtarget features for now as they continue to
seem the best fit given the lack of other retpoline like constructs so
far.

The LLVM side is pretty simple. I'd like to eventually get rid of the
old feature, but not sure what backwards compatibility issues that will
cause.

This does remove the "implies" from requesting an external thunk. This
always seemed somewhat questionable and is now clearly not desirable --
you specify a thunk the same way no matter which set of things are
getting retpolines.

I really want to keep this nicely isolated from end users and just an
LLVM implementation detail, so I've moved the `-mretpoline` flag in
Clang to no longer rely on a specific subtarget feature by that name and
instead to be directly handled. In some ways this is simpler, but in
order to preserve existing behavior I've had to add some fallback code
so that users who relied on merely passing -mretpoline-external-thunk
continue to get the same behavior. We should eventually remove this
I suspect (we have never tested that it works!) but I've not done that
in this patch.

Differential Revision: https://reviews.llvm.org/D51150

llvm-svn: 340515
2018-08-23 06:06:38 +00:00
Nico Weber 75ae75cd17 [clang-cl] Add support for /arch:AVX512F and /arch:AVX512
For /arch:AVX512F:
clang-cl and cl.exe both defines __AVX512F__ __AVX512CD__.
clang-cl also defines __AVX512ER__ __AVX512PF__.
64-bit cl.exe also defines (according to /Bz) _NO_PREFETCHW.

For /arch:AVX512:
clang-cl and cl.exe both define
__AVX512F__ __AVX512CD__ __AVX512BW__ __AVX512DQ__ __AVX512VL__.
64-bit cl.exe also defines _NO_PREFETCHW.

So not 100% identical, but pretty close.

Also refactor the existing AVX / AVX2 code to not repeat itself in both the
32-bit and 64-bit cases.

https://reviews.llvm.org/D42538

llvm-svn: 323433
2018-01-25 15:24:43 +00:00
Nico Weber 691300c945 clang-cl: Simplify handling of /arch: flag.
r213083 initially implemented /arch: support by mapping it to CPU features.
Then r241077 additionally mapped it to CPU, which made the feature flags
redundant (if harmless). This change here removes the redundant mapping to
feature flags, and rewrites test/Driver/cl-x86-flags.c to be a bit more of an
integration test that checks for preprocessor defines like AVX (like documented
on MSDN) instead of for driver flags.

To keep emitting warn_drv_unused_argument, use getLastArgNoClaim() followed by an explicit claim() if needed.

This is in preparation for adding support for /arch:AVX512(F).

No intended behavior change.

https://reviews.llvm.org/D42497

llvm-svn: 323426
2018-01-25 14:38:29 +00:00
Erich Keane 2b9657b570 Remove Bitrig: Clang Changes
Bitrig code has been merged back to OpenBSD, thus the OS has been abandoned.

Differential Revision: https://reviews.llvm.org/D35708

llvm-svn: 308797
2017-07-21 22:46:31 +00:00
Craig Topper 451eedd3b6 [X86] Remove some code that tries to disable HLE feature. This feature flag was removed from the backend.
llvm-svn: 299416
2017-04-04 06:38:44 +00:00
David L. Jones f561abab56 [Driver] Consolidate tools and toolchains by target platform. (NFC)
Summary:
(This is a move-only refactoring patch. There are no functionality changes.)

This patch splits apart the Clang driver's tool and toolchain implementation
files. Each target platform toolchain is moved to its own file, along with the
closest-related tools. Each target platform toolchain has separate headers and
implementation files, so the hierarchy of classes is unchanged.

There are some remaining shared free functions, mostly from Tools.cpp. Several
of these move to their own architecture-specific files, similar to r296056. Some
of them are only used by a single target platform; since the tools and
toolchains are now together, some helpers now live in a platform-specific file.
The balance are helpers related to manipulating argument lists, so they are now
in a new file pair, CommonArgs.h and .cpp.

I've tried to cluster the code logically, which is fairly straightforward for
most of the target platforms and shared architectures. I think I've made
reasonable choices for these, as well as the various shared helpers; but of
course, I'm happy to hear feedback in the review.

There are some particular things I don't like about this patch, but haven't been
able to find a better overall solution. The first is the proliferation of files:
there are several files that are tiny because the toolchain is not very
different from its base (usually the Gnu tools/toolchain). I think this is
mostly a reflection of the true complexity, though, so it may not be "fixable"
in any reasonable sense. The second thing I don't like are the includes like
"../Something.h". I've avoided this largely by clustering into the current file
structure. However, a few of these includes remain, and in those cases it
doesn't make sense to me to sink an existing file any deeper.

Reviewers: rsmith, mehdi_amini, compnerd, rnk, javed.absar

Subscribers: emaste, jfb, danalbert, srhines, dschuff, jyknight, nemanjai, nhaehnle, mgorny, cfe-commits

Differential Revision: https://reviews.llvm.org/D30372

llvm-svn: 297250
2017-03-08 01:02:16 +00:00