This matches gcc -static-pie. The intention is to prevent dynamic
relocations in read-only segments.
In ld.bfd and gold, -z notext is the default. If text relocations are needed:
* -z notext: allow and emit DF_TEXTREL.
DF_TEXTREL is not emitted if there is no text relocation.
* -z text: error
In lld, -z text is the default (this change is a no-op).
* -z text: error on text relocations
* -z notext: allow text relocations, and emit DF_TEXTREL no matter whether
text relocations exist.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D62606
llvm-svn: 362050
Summary:
After https://github.com/emscripten-core/emscripten/pull/8651, Emscripten
supports the full UBSan runtime. This includes the VPtr sanitizer.
This diff allows clang to generate code that uses the VPtr sanitizer for
Emscripten.
Patch by Guanzhong Chen
Reviewers: tlively, aheejin
Reviewed By: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, sunfish, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D62559
llvm-svn: 362004
This is useful when looking for directories or files relative to the
toolchain root, e.g. include/c++/v1. This change also adds a test
to make sure this functionality doesn't regress in the future.
Differential Revision: https://reviews.llvm.org/D62558
llvm-svn: 361903
Currently the `-working-directory` option does not actually impact the working
directory for all of the clang driver, it only impacts how files are looked up
to make sure they exist. This means that that clang passes the wrong paths
to -fdebug-compilation-dir and -coverage-notes-file.
This patch fixes that by changing all the places in the driver where we convert
to absolute paths to use the VFS, and then calling setCurrentWorkingDirectory on
the VFS. This also changes the default VFS for `Driver` to use a virtualized
working directory, instead of changing the process's working directory.
Differential Revision: https://reviews.llvm.org/D62271
llvm-svn: 361885
This is a follow up to r361432, changing the layout of per-target
runtimes to more closely resemble multiarch. While before, we used
the following layout:
[RESOURCE_DIR]/<target>/lib/libclang_rt.<runtime>.<ext>
Now we use the following layout:
[RESOURCE_DIR]/lib/<target>/libclang_rt.<runtime>.<ext>
This also more closely resembles the existing "non-per-target" layout:
[RESOURCE_DIR]/lib/<os>/libclang_rt.<runtime>-<arch>.<ext>
This change will enable further simplification of the driver logic
in follow up changes.
Differential Revision: https://reviews.llvm.org/D62469
llvm-svn: 361784
This is a follow up to r361432 and r361504 which addresses issues
introduced by those changes. Specifically, it avoids duplicating
file and runtime paths in case when the effective triple is the
same as the cannonical one. Furthermore, it fixes the broken multilib
setup in the Fuchsia driver and deduplicates some of the code.
Differential Revision: https://reviews.llvm.org/D62442
llvm-svn: 361709
This is in line with other platforms.
Also, move the single statement methods into the header (also
in line with other platform).
Differential Revision: https://reviews.llvm.org/D62406
llvm-svn: 361651
New -cc1 arguments, such as -faddrsig, have started appearing after the
input name. I personally find it convenient for the input to be the last
argument to the compile command line, since I often need to edit it when
running crash reproduction scripts.
Differential Revision: https://reviews.llvm.org/D62270
llvm-svn: 361530
OptTable treats arguments starting with / that aren't a known option
as filenames. This means lld-link's and clang-cl's typo correction for
unknown flags didn't do spell checking for misspelled options that start
with /.
I first tried changing OptTable, but that got pretty messy, see PR41787
comments 2 and 3.
Instead, let lld-link's and clang's (including clang-cl's) "file not
found" diagnostic check if a non-existent file looks like it could be a
mis-spelled option, and if so add a "did you mean" suggestion to the
"file not found" diagnostic.
While here, make formatting of a few diagnostics a bit more
self-consistent.
Fixes PR41787.
Differential Revision: https://reviews.llvm.org/D62276
llvm-svn: 361518
This addresses the issue introduced in r361432 where we would only
try effective triple but not the normalized one as we do for other
runtimes.
Differential Revision: https://reviews.llvm.org/D62286
llvm-svn: 361504
This change is a consequence of the discussion in "RFC: Place libs in
Clang-dedicated directories", specifically the suggestion that
libunwind, libc++abi and libc++ shouldn't be using Clang resource
directory. Tools like clangd make this assumption, but this is
currently not true for the LLVM_ENABLE_PER_TARGET_RUNTIME_DIR build.
This change addresses that by moving the output of these libraries to
lib/$target/c++ and include/c++ directories, leaving resource directory
only for compiler-rt runtimes and Clang builtin headers.
Differential Revision: https://reviews.llvm.org/D59168
llvm-svn: 361432
Before e97b5f5cf3 ([clang][Darwin] Refactor header search path logic
into the driver), both --sysroot and -isysroot worked to specify where
to look for system and C++ headers on Darwin. However, that change
caused clang to start ignoring --sysroot.
This fixes the regression, and adds tests.
(I also note that on all other platforms, clang seems to almost
completely ignore -isysroot, but that's another issue...)
Differential Revision: https://reviews.llvm.org/D62268
llvm-svn: 361429
Summary:
Values returned by GCCInstallation.getParentLibPath() and
GCCInstallation.getTriple() are not valid unless
GCCInstallation.isValid() returns true. This has previously been
ignored, and the former two values were used without checking whether
GCCInstallation is valid. This led to the bad path "/../bin" being added
to the list of program paths.
author: danielmentz "Daniel Mentz <danielmentz@google.com>"
Reviewers: #clang, tstellar, srhines
Reviewed By: srhines
Subscribers: danielmentz, ormris, nickdesaulniers, srhines, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D57930
llvm-svn: 361314
Summary:
This commit moves the logic for determining system, resource and C++
header search paths from CC1 to the driver. This refactor has already
been made for several platforms, but Darwin had been left behind.
This refactor tries to implement the previous search path logic with
perfect accuracy. In particular, the order of all include paths inside
CC1 and all paths that were skipped because nonexistent are conserved
after the refactor. This change was also tested against a code base
of significant size and revealed no problems.
Reviewers: jfb, arphaman
Subscribers: nemanjai, javed.absar, kbarton, christof, jkorous, dexonsmith, jsji, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D61963
llvm-svn: 361278
Defines macro ARM_FEATURE_CMSE to 1 for v8-M targets and introduces
-mcmse option which for v8-M targets sets ARM_FEATURE_CMSE to 3.
A diagnostic is produced when the option is given on architectures
without support for Security Extensions.
Reviewed By: dmgreen, snidertm
Differential Revision: https://reviews.llvm.org/D59879
llvm-svn: 361261
Summary:
This patch modifies the AVR toolchain so that if avr-gcc and avr-libc
are detected during compilation, the CRT, libgcc, libm, and libc anre
linked.
This matches avr-gcc's default behaviour, and the expected behaviour of
all C compilers - including the C runtime.
avr-gcc also needs a -mmcu specified in order to link runtime libraries.
The difference betwen this patch and avr-gcc is that this patch will
warn users whenever they compile without a runtime, as opposed to GCC,
which silently trims the runtime libs from the linker arguments when no
-mmcu is specified.
Reviewers: aaron.ballman, kparzysz, asb, hfinkel, brucehoult, TimNN
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D54334
llvm-svn: 361116
This is needed so lld-link can find clang_rt.profile when self hosting
on Windows with PGO. Using clang-cl as a linker knows to add the library
but self hosting, using -DCMAKE_LINKER=<...>/lld-link.exe doesn't.
Differential Revision: https://reviews.llvm.org/D61742
llvm-svn: 360674
Summary: This patches fixes an issue in which the __clang_cuda_cmath.h header is being included even when cmath or math.h headers are not included.
Reviewers: jdoerfert, ABataev, hfinkel, caomhin, tra
Reviewed By: tra
Subscribers: tra, mgorny, guansong, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D61765
llvm-svn: 360626
This driver flag is useful when users want to link against the compiler's
builtins, but nothing else, and so use flags like -nostdlib.
Darwin can't use -nolibc & nostdlib++ like other platforms on because we
disable all runtime lib linking with -static, which we still want to have
an option to link with the builtins.
Differential Revision: https://reviews.llvm.org/D58320
llvm-svn: 360483
Summary:
When using `clang -mcpu=CPUNAME+FEATURELIST`,
the implied features defined by CPUNAME are
not obtained, as the entire string is passed.
This fixes that by spiting the cpuname
string in the first `+`, if any.
For example, when using
```clang -### --target=arm-arm-none-eabi -march=armv7-a -mcpu=cortex-a8+nocrc```
the intrinsic
```"target-feature" "+dsp"```
implied by `cortex-a8` is missing.
Reviewers: keith.walker.arm, DavidSpickett, carwil
Reviewed By: DavidSpickett
Subscribers: javed.absar, kristof.beyls, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D61668
llvm-svn: 360324
Summary:
In this patch we propose a temporary solution to resolving math functions for the NVPTX toolchain, temporary until OpenMP variant is supported by Clang.
We intercept the inclusion of math.h and cmath headers and if we are in the OpenMP-NVPTX case, we re-use CUDA's math function resolution mechanism.
Authors:
@gtbercea
@jdoerfert
Reviewers: hfinkel, caomhin, ABataev, tra
Reviewed By: hfinkel, ABataev, tra
Subscribers: JDevlieghere, mgorny, guansong, cfe-commits, jdoerfert
Tags: #clang
Differential Revision: https://reviews.llvm.org/D61399
llvm-svn: 360265
This commit appears to be breaking stage-2 builds on GreenDragon. The
OpenMP wrappers for cmath and math.h are copied into the root of the
resource directory and cause a cyclic dependency in module 'Darwin':
Darwin -> std -> Darwin. This blows up when CMake is testing for modules
support and breaks all stage 2 module builds, including the ThinLTO bot
and all LLDB bots.
CMake Error at cmake/modules/HandleLLVMOptions.cmake:497 (message):
LLVM_ENABLE_MODULES is not supported by this compiler
llvm-svn: 360192
Summary:
In this patch we propose a temporary solution to resolving math functions for the NVPTX toolchain, temporary until OpenMP variant is supported by Clang.
We intercept the inclusion of math.h and cmath headers and if we are in the OpenMP-NVPTX case, we re-use CUDA's math function resolution mechanism.
Authors:
@gtbercea
@jdoerfert
Reviewers: hfinkel, caomhin, ABataev, tra
Reviewed By: hfinkel, ABataev, tra
Subscribers: mgorny, guansong, cfe-commits, jdoerfert
Tags: #clang
Differential Revision: https://reviews.llvm.org/D61399
llvm-svn: 360063
When user specifies non-existent directory to -fcrash-diagnostics-dir,
create it rather than failing with an error as would be the case before.
Differential Revision: https://reviews.llvm.org/D61542
llvm-svn: 359954
Summary:
The bug was reported on the OpenMP-dev list:
.../obj-release/lib/clang/9.0.0/include/__clang_cuda_intrinsics.h:173:35: error: '__nvvm_shfl_sync_idx_i32' needs target feature ptx60|ptx61|ptx63|ptx64
__MAKE_SYNC_SHUFFLES(__shfl_sync, __nvvm_shfl_sync_idx_i32,
This problem occurs when trying to compile a .cu file that requires a newer ptx version (>ptx60 in this case) than ptx42.
Reviewers: tra, ABataev, caomhin
Reviewed By: tra
Subscribers: jdoerfert, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D61474
llvm-svn: 359910
CUDA 10.1 tools deprecated some command line options.
fatbinary no longer needs --cuda.
Differential Revision: https://reviews.llvm.org/D61470
llvm-svn: 359838
When compiler-rt is selected as the runtime library for Linux targets
use its crtbegin.o/crtend.o implemenetation rather than platform one
if available.
Differential Revision: https://reviews.llvm.org/D59264
llvm-svn: 359603
This introduces a support for multilibs to Fuchsia driver. Unlike the
existing multilibs that are used primarily for handling different
architecture variants, we use multilibs to handle different variants
of Clang runtime libraries: -fsanitize=address and -fno-exceptions
are the two we support initially. This replaces the existing support
for sanitized runtimes libraries that was only used by Fuchsia driver
and it also refactors some of the logic to allow sharing between GNU
and Fuchsia drivers.
Differential Revision: https://reviews.llvm.org/D61040
llvm-svn: 359360
When more than one multilib flag matches, try to select the best
possible match based on priority. When two different multilibs with
the same same priority match, we still throw an error matching the
existing behavior.
Differential Revision: https://reviews.llvm.org/D60990
llvm-svn: 359359
is running in a toolchain outside of xcode
'libarclite' usually lives in the same toolchain as 'clang'. However, the
Swift open source toolchains for macOS distribute Clang without 'libarclite'.
In that case, to allow the linker to find 'libarclite', we point to the
'libarclite' that should be in the XcodeDefault toolchain instead. The
path to the toolchain is inferred from the SDK path if it's specified.
https://bugs.swift.org/browse/SR-9972
rdar://49947573
llvm-svn: 359353
These builtins provide access to the new integer and
sub-integer variants of MMA (matrix multiply-accumulate) instructions
provided by CUDA-10.x on sm_75 (AKA Turing) GPUs.
Also added a feature for PTX 6.4. While Clang/LLVM does not generate
any PTX instructions that need it, we still need to pass it through to
ptxas in order to be able to compile code that uses the new 'mma'
instruction as inline assembly (e.g used by NVIDIA's CUTLASS library
https://github.com/NVIDIA/cutlass/blob/master/cutlass/arch/mma.h#L101)
Differential Revision: https://reviews.llvm.org/D60279
llvm-svn: 359248
Path lists on windows should always be separated by semicolons, not
colons. Reuse llvm::sys::EnvPathSeparator for this purpose (as that's
also a path list that is separated in the same way).
Alternatively, this could just be a local ifdef _WIN32 in this function,
or generalizing the existing EnvPathSeparator to e.g. a
llvm::sys::path::PathListSeparator?
Differential Revision: https://reviews.llvm.org/D61121
llvm-svn: 359233
The behaviour of not quoting spaces appears to have been introduced by
mistake in r190620.
Patch by Brad Moody!
Differential revision: https://reviews.llvm.org/D60997
llvm-svn: 359077
Port mmintrin.h which include x86 MMX intrinsics implementation to PowerPC platform (using Altivec).
To make the include process correct, PowerPC's toolchain class is overrided to insert new headers directory (named ppc_wrappers) into the path. Basic test cases for several intrinsic functions are added.
The header is mainly developed by Steven Munroe, with contributions from Paul Clarke, Bill Schmidt, Jinsong Ji and Zixuan Wu.
Reviewed By: Jinsong Ji
Differential Revision: https://reviews.llvm.org/D59924
llvm-svn: 358949
Previously, if the MSVC installation isn't detected properly, clang
will later just fail to execute link.exe.
This improves using clang in msvc mode on linux, where one intentionally
might not want to point clang to the MSVC installation itself (which
isn't executable as such), but where a link.exe named wine wrapper is
available in the path next to a cl.exe named wine wrapper.
Differential Revision: https://reviews.llvm.org/D60094
llvm-svn: 358778
Gold and ld on Linux already support saving stats, but the
infrastructure is missing on Darwin. Unfortunately it seems like the
configuration from lib/LTO/LTO.cpp is not used.
This patch adds a new LTOStatsFile option and adds plumbing in Clang to
use it on Darwin, similar to the way remarks are handled.
Currnetly the handling of LTO flags seems quite spread out, with a bunch
of duplication. But I am not sure if there is an easy way to improve
that?
Reviewers: anemet, tejohnson, thegameg, steven_wu
Reviewed By: steven_wu
Differential Revision: https://reviews.llvm.org/D60516
llvm-svn: 358753
If accessing the MSVC installation root directly on a case sensitive
filesystem, these details matter.
Differential Revision: https://reviews.llvm.org/D60627
llvm-svn: 358662
Summary:
When -gsplit-dwarf is used together with other -g options, in most cases
the computed debug info level is decided by the last -g option, with one
special case (see below). This patch drops that special case and thus
makes it easy to reason about:
// If a lower debug level -g comes after -gsplit-dwarf, in some cases
// -gsplit-dwarf is cancelled.
-gsplit-dwarf -g0 => 0
-gsplit-dwarf -gline-directives-only => DebugDirectivesOnly
-gsplit-dwarf -gmlt -fsplit-dwarf-inlining => 1
-gsplit-dwarf -gmlt -fno-split-dwarf-inlining => 1 + split
// If -gsplit-dwarf comes after -g options, with this patch, the net
// effect is 2 + split for all combinations
-g0 -gsplit-dwarf => 2 + split
-gline-directives-only -gsplit-dwarf => 2 + split
-gmlt -gsplit-dwarf -fsplit-dwarf-inlining => 2 + split
-gmlt -gsplit-dwarf -fno-split-dwarf-inlining => 1 + split (before) 2 + split (after)
The last case has been changed. In general, if the user intends to lower
debug info level, place that -g option after -gsplit-dwarf.
Some context:
In gcc, the last of -gsplit-dwarf -g0 -g1 -g2 -g3 -ggdb[0-3] -gdwarf-*
... decides the debug info level (-gsplit-dwarf -gdwarf-* have level 2).
It is a bit unfortunate that -gsplit-dwarf -gdwarf-* ... participate in
the level computation but that is the status quo.
Reviewers: dblaikie, echristo, probinson
Reviewed By: dblaikie, probinson
Subscribers: probinson, aprantl, jdoerfert, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D59923
llvm-svn: 358544
LLDB can't currently handle Clang's default (limit/no-standalone) DWARF,
so platforms that default to LLDB (Darwin) or anyone else manually
requesting LLDB tuning, should also get standalone DWARF.
That doesn't mean a user can't explicitly enable (because they have
other reasons to prefer standalone DWARF (such as that they're only
building half their application with debug info enabled, and half
without - or because they're tuning for GDB, but want to be able to use
it under LLDB too (this is the default on FreeBSD))) or disable (testing
LLDB fixes/improvements that handle no-standalone mode, building C code,
perhaps, which wouldn't have the LLDB<>no-standalone conflict, etc) the
feature regardless of the tuning.
llvm-svn: 358464
Use -mlink-builtin-bitcode instead of llvm-link to link
device library so that device library bitcode and user
device code can be compiled in a consistent way.
This is the same approach used by CUDA and OpenMP.
Differential Revision: https://reviews.llvm.org/D60513
llvm-svn: 358290
Disabled by default as this is still an experimental feature.
Reviewed By: thakis
Differential Revision: https://reviews.llvm.org/D59221
llvm-svn: 358285
Summary:
The current llvm/clang et al. project can be built with the latest developer toolset (devtoolset-8) on RHEL, which provides GCC 8.2.1.
However, the result compiler will not identify this toolset itself when compiling programs, which is of course not desirable.
After the patch - which simply adds the name of the developer toolset to the existing list - it gets identified and selected, as shown below:
[bamboo@bamboo llvm-project]$ clang -v
clang version 9.0.0 (https://github.com/llvm/llvm-project.gite5ac385fb1)
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir: /home/bamboo/llvm/bin
Found candidate GCC installation: /opt/rh/devtoolset-4/root/usr/lib/gcc/x86_64-redhat-linux/5.2.1
Found candidate GCC installation: /opt/rh/devtoolset-7/root/usr/lib/gcc/x86_64-redhat-linux/7
Found candidate GCC installation: /opt/rh/devtoolset-8/root/usr/lib/gcc/x86_64-redhat-linux/8
Found candidate GCC installation: /usr/lib/gcc/x86_64-redhat-linux/4.8.2
Found candidate GCC installation: /usr/lib/gcc/x86_64-redhat-linux/4.8.5
Selected GCC installation: /opt/rh/devtoolset-8/root/usr/lib/gcc/x86_64-redhat-linux/8
Candidate multilib: .;@m64
Candidate multilib: 32;@m32
Selected multilib: .;@m64
Patch By: Radu-Adrian Popescu
Reviewers: tstellar, fedor.sergeev
Reviewed By: tstellar
Subscribers: jdoerfert, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D59987
llvm-svn: 358002
When setting up library and tools paths when detecting an accompanying GCC
installation only riscv32 was handled. As a consequence when targetting
riscv64 neither the linker nor libraries would be found. This adds handling
and tests for riscv64.
Differential Revision: https://reviews.llvm.org/D53392
Patch by Edward Jones.
llvm-svn: 357699
In case of N64 ABI toolchain paths migth have `mips-linux-gnuabi64`
or `mips-linux-gnu` directory regardless of selected environment.
Check both variants while detecting a multiarch triple.
Fix for the bug https://bugs.llvm.org/show_bug.cgi?id=41204
llvm-svn: 357506
This change adds hierarchical "time trace" profiling blocks that can be visualized in Chrome, in a "flame chart" style. Each profiling block can have a "detail" string that for example indicates the file being processed, template name being instantiated, function being optimized etc.
This is taken from GitHub PR: https://github.com/aras-p/llvm-project-20170507/pull/2
Patch by Aras Pranckevičius.
Differential Revision: https://reviews.llvm.org/D58675
llvm-svn: 357340
Android does not allow shared text relocations. Enable the linker
warning to detect them by default.
Reviewers: srhines, pirama
Reviewed By: srhines
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D53344
llvm-svn: 357296
Effectively reverts r337612. The issues that cropped up with the last
attempt appear to have gone away.
Differential Revision: https://reviews.llvm.org/D59008
llvm-svn: 357285
Add an -mtp=el[0-3] option to select which of the AArch64 thread ID registers
will be used for the TLS base pointer.
This is a followup to rL356657 which added subtarget features to enable
accesses to the privileged thread ID registers.
Patch by Philip Derrin!
Differential revision: https://reviews.llvm.org/D59631
llvm-svn: 357250
In gcc, -gsplit-dwarf is handled in gcc/gcc.c as a spec
(ASM_FINAL_SPEC): objcopy --extract-dwo + objcopy --strip-dwo. In
gcc/opts.c, -gsplit_dwarf has the same semantic of a -g. Except for the
availability of the external command 'objcopy', nothing precludes the
feature working on other ELF OSes. llvm doesn't use objcopy, so it doesn't
have to exclude other OSes.
llvm-svn: 357150
Since AArch64 has default outlining behaviour, we need to make sure that
-mno-outline is actually passed along to the linker in this case. Otherwise,
it will run by default on minsize functions even when -mno-outline is specified.
Also fix the darwin-ld test for this, which wasn't actually doing anything.
llvm-svn: 357031
The RISC-V assembler needs the target ABI because it defines a flag of the ELF
file, as described in [1].
Make clang (the driver) to pass the target ABI to -cc1as in exactly the same
way it does for -cc1.
Currently -cc1as knows about -target-abi but is not handling it. Handle it and
pass it to the MC layer via MCTargetOptions.
[1] https://github.com/riscv/riscv-elf-psabi-doc/blob/master/riscv-elf.md#file-header
Differential Revision: https://reviews.llvm.org/D59298
llvm-svn: 356981
We can't (don't want to) honor the same set of "-fuse-ld" flags with
WebAssembly since the ELF linkers (ld.lld, ld.gnu, etc) don't work with
wasm object files.
Instead we implement our own linker finding logic, similar or other
non-ELF platforms like MSVC.
We've had a few issues with CLANG_DEFAULT_LINKER overriding the
WebAssembly linker which doesn't make sense since there is no generic
linker that can handle WebAssembly today.
Differential Revision: https://reviews.llvm.org/D59743
llvm-svn: 356953
Summary:
This eliminates a linker error the user might otherwise see about how
using the 'atomics' feature requires --shared-memory.
Reviewers: sbc100, aheejin
Subscribers: dschuff, jgravelle-google, sunfish, jfb, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D59721
llvm-svn: 356817
-malign-double is currently only implemented in the -cc1 interface. But its declared in Options.td so it is a driver option too. But you try to use it with the driver you'll get a message about the option being unused.
This patch teaches the driver to pass the option through to cc1 so it won't be unused. The Options.td says the option is x86 only but I didn't see any x86 specific code in its impementation in cc1 so not sure if the documentation is wrong or if I should only pass this option through the driver on x86 targets.
Differential Revision: https://reviews.llvm.org/D59624
llvm-svn: 356706
"clang++ hello.cc --rtlib=compiler-rt"
now can works without specifying additional unwind or exception
handling libraries.
This reworked version of the feature no longer modifies today's default
unwind library for compiler-rt: which is nothing. Rather, a user
can specify -DCLANG_DEFAULT_UNWINDLIB=libunwind when configuring
the compiler.
This should address the issues from the previous version.
Update tests for new --unwindlib semantics.
Differential Revision: https://reviews.llvm.org/D59109
llvm-svn: 356508
Change the HIP Toolchain to pass the OPT_mllvm options into OPT and LLC stages. Added a lit test to verify the command args.
Reviewers: yaxunl
Differential Revision: https://reviews.llvm.org/D59316
llvm-svn: 356277
The above commit breaks the usage of PGO and LTO when -fprofile-use is
supplied without a path. This patch changes the usage of this argument
to be inline with its use in addPGOAndCoverageFlags().
Differential revision: https://reviews.llvm.org/D59304
llvm-svn: 356111
Currently we have -Rpass for filtering the remarks that are displayed as
diagnostics, but when using -fsave-optimization-record, there is no way
to filter the remarks while generating them.
This adds support for filtering remarks by passes using a regex.
Ex: `clang -fsave-optimization-record -foptimization-record-passes=inline`
will only emit the remarks coming from the pass `inline`.
This adds:
* `-fsave-optimization-record` to the driver
* `-opt-record-passes` to cc1
* `-lto-pass-remarks-filter` to the LTOCodeGenerator
* `--opt-remarks-passes` to lld
* `-pass-remarks-filter` to llc, opt, llvm-lto, llvm-lto2
* `-opt-remarks-passes` to gold-plugin
Differential Revision: https://reviews.llvm.org/D59268
Original llvm-svn: 355964
llvm-svn: 355984
Currently we have -Rpass for filtering the remarks that are displayed as
diagnostics, but when using -fsave-optimization-record, there is no way
to filter the remarks while generating them.
This adds support for filtering remarks by passes using a regex.
Ex: `clang -fsave-optimization-record -foptimization-record-passes=inline`
will only emit the remarks coming from the pass `inline`.
This adds:
* `-fsave-optimization-record` to the driver
* `-opt-record-passes` to cc1
* `-lto-pass-remarks-filter` to the LTOCodeGenerator
* `--opt-remarks-passes` to lld
* `-pass-remarks-filter` to llc, opt, llvm-lto, llvm-lto2
* `-opt-remarks-passes` to gold-plugin
Differential Revision: https://reviews.llvm.org/D59268
llvm-svn: 355964
This change introduces support for object files in addition to static
and shared libraries which were already supported which requires
changing the type of the argument from boolean to an enum.
Differential Revision: https://reviews.llvm.org/D56044
llvm-svn: 355891
It hasn't seen active development in years, and it hasn't reached a
state where it was useful.
Remove the code until someone is interested in working on it again.
Differential Revision: https://reviews.llvm.org/D59133
llvm-svn: 355862
This change is a consequence of the discussion in "RFC: Place libs in
Clang-dedicated directories", specifically the suggestion that
libunwind, libc++abi and libc++ shouldn't be using Clang resource
directory. Tools like clangd make this assumption, but this is
currently not true for the LLVM_ENABLE_PER_TARGET_RUNTIME_DIR build.
This change addresses that by moving the output of these libraries to
lib/<target> and include/ directories, leaving resource directory only
for compiler-rt runtimes and Clang builtin headers.
Differential Revision: https://reviews.llvm.org/D59013
llvm-svn: 355665
When -fno-gpu-rdc is set, device code is compiled, linked, and assembled into fat binary
and embedded as string in object files. The object files are normal object files which
can be linked by host linker. In the linking stage, the object files should not be unbundled
when -fno-gpu-rdc is set since they are normal object files, not bundles. The object files
only need to be unbundled when -fgpu-rdc is set.
Currently clang always unbundles object files, disregarding -fgpu-rdc option.
This patch fixes that.
Differential Revision: https://reviews.llvm.org/D58917
llvm-svn: 355410
When -forder-file-instrumentation is on, we pass llvm flag to enable the order file instrumentation pass.
https://reviews.llvm.org/D58751
llvm-svn: 355333
Part 1 of CSPGO change in Clang. This includes changes in clang options
and calls to llvm PassManager. Tests will be committed in part2.
This change needs the PassManager change in llvm.
Differential Revision: https://reviews.llvm.org/D54176
llvm-svn: 355331
Support locating the libc++ header files relatively to the clang
executable, in addition to the default system path. This is meant
to cover two use cases: running just-built clang from the install
directory, and running installed clang from non-standard location
(e.g. /usr/local).
This is the first step towards ensuring that tests of more LLVM projects
can work out-of-the-box within the build tree, and use the correct set
of headers (rather than e.g. mixing just-built clang+libcxx with system
install of libcxx). It avoids requiring the user to hack around missing
include paths, or LLVM build system to replicate system-specific C++
library defaults in order to append appropriate paths implicitly.
Differential Revision: https://reviews.llvm.org/D58592
llvm-svn: 355282
Summary:
To prevent the instability of bulk-memory in the wasm backend from
blocking separate pthread testing, temporarily remove the logic that
adds -mbulk-memory in the presence of -pthread. Since browsers will
ship bulk memory before or alongside threads, this change will be
reverted as soon as bulk memory has stabilized in the backend.
Reviewers: sbc100
Subscribers: dschuff, jgravelle-google, aheejin, sunfish, jfb, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D58854
llvm-svn: 355248
enum SanitizerOrdinal has reached maximum capacity, this change extends the capacity to 128 sanitizer checks.
This can eventually allow us to add gcc 8's options "-fsanitize=pointer-substract" and "-fsanitize=pointer-compare".
This is a recommit of r354873 but with a fix for unqualified lookup error in lldb cmake build bot.
Fixes: https://llvm.org/PR39425
Differential Revision: https://reviews.llvm.org/D57914
llvm-svn: 355190
Summary:
In the clang UI, replaces -mthread-model posix with -matomics as the
source of truth on threading. In the backend, replaces
-thread-model=posix with the atomics target feature, which is now
collected on the WebAssemblyTargetMachine along with all other used
features. These collected features will also be used to emit the
target features section in the future.
The default configuration for the backend is thread-model=posix and no
atomics, which was previously an invalid configuration. This change
makes the default valid because the thread model is ignored.
A side effect of this change is that objects are never emitted with
passive segments. It will instead be up to the linker to decide
whether sections should be active or passive based on whether atomics
are used in the final link.
Reviewers: aheejin, sbc100, dschuff
Subscribers: mehdi_amini, jgravelle-google, hiraditya, sunfish, steven_wu, dexonsmith, rupprecht, jfb, jdoerfert, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D58742
llvm-svn: 355112
Remove comments and tests about passing -mcode-object-v3 to driver since it does
not work. Other -m options are OK.
Also put back -mattr=-code-object-v3 since HIP is still not ready for code object
v3.
Differential Revision: https://reviews.llvm.org/D57977
llvm-svn: 355106
enum SanitizerOrdinal has reached maximum capacity, this change extends the capacity to 128 sanitizer checks.
This can eventually allow us to add gcc 8's options "-fsanitize=pointer-substract" and "-fsanitize=pointer-compare".
Fixes: https://llvm.org/PR39425
Differential Revision: https://reviews.llvm.org/D57914
llvm-svn: 354873
Summary: This change mimics GCC's support for the "-static-pie" argument.
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D58307
llvm-svn: 354502
A faster way to reduce the values in teams reductions was found, the
codegen is updated to use this faster algorithm and new runtime functions.
llvm-svn: 354479
This adds ACLE-defined macros to test for code being compiled in the ROPI and
RWPI position-independence modes.
Differential revision: https://reviews.llvm.org/D23610
llvm-svn: 354265
This can be used to disable libc linking. This flag is supported by
GCC since version 9 as well as some Clang target toolchains.
Differential Revision: https://reviews.llvm.org/D58326
llvm-svn: 354210
This can be used to disable libc linking. This flag is supported by
GCC since version 9 as well as some Clang target toolchains. This
change also includes tests for all -no* flags which previously weren't
covered.
Differential Revision: https://reviews.llvm.org/D58325
llvm-svn: 354208
Summary:
There are an insignificant number of ARM Android devices that don't
support NEON. Default to using NEON since that will improve
performance on the majority of devices. Users that need to target
non-NEON devices can still explicitly disable NEON.
Reviewers: srhines, pirama, kristof.beyls
Reviewed By: pirama
Subscribers: efriedma, javed.absar, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D58153
llvm-svn: 354166
Summary:
instrprof-darwin-exports.c test fails on Darwin due to r354064.
Updated clang list of exported symbols to fix the issue.
Reviewers: vsk
Reviewed By: vsk
Subscribers: davidxl, efriedma
Differential Revision: https://reviews.llvm.org/D58259
llvm-svn: 354089
Instead of letting a program fail at runtime, emit an error during
compilation.
rdar://problem/12206955
Reviewers: dexonsmith, bob.wilson, steven_wu
Reviewed By: steven_wu
Subscribers: jkorous, cfe-commits
Differential Revision: https://reviews.llvm.org/D57991
llvm-svn: 354084
This is a follow up to D48580 and D48581 which allows reserving
arbitrary general purpose registers with the exception of registers
with special purpose (X8, X16-X18, X29, X30) and registers used by LLVM
(X0, X19). This change also generalizes some of the existing logic to
rely entirely on values generated from tablegen.
Differential Revision: https://reviews.llvm.org/D56305
llvm-svn: 353957
Allow the compile options for -m such as -mxnack/-mno-xnack, -msram-ecc/-mno-sram-ecc, -mcode-object-v3/-mno-code-object-v3 to propagate into LLC args. Fix an issue where -mattr was pushed even when it was empty.
Also add lit tests to verify features are properly passed.
Differential Revision: https://reviews.llvm.org/D57977
Reviewers: yaxunl, kzhuravl
llvm-svn: 353952
Profiling still doesn't seem to work properly, but this at least
hooks up the library and eases completing whatever is missing.
Differential Revision: https://reviews.llvm.org/D58107
llvm-svn: 353917
Allow the compile options for -m such as -mxnack/-mno-xnack, -msram-ecc/-mno-sram-ecc, -mcode-object-v3/-mno-code-object-v3 to propagate into LLC args.
Also add lit tests to verify features are properly passed.
Differential Revision: https://reviews.llvm.org/D57977
Reviewers: yaxunl, kzhuravl
llvm-svn: 353880
Relocatable code generation is meaningless on MSP430, as the platform is too small to use shared libraries.
Patch by Dmitry Mikushev!
Differential Revision: https://reviews.llvm.org/D56927
llvm-svn: 353877
Summary:
There have been three options related to threads and users had to set
all three of them separately to get the correct compilation results.
This makes sure the relationship between the options makes sense and
sets necessary options for users if only part of the necessary options
are specified. This does:
- Remove `-matomics`; this option alone does not enable anything, so
removed it to not confuse users.
- `-mthread-model posix` sets `-target-feature +atomics`
- `-pthread` sets both `-target-feature +atomics` and
`-mthread-model posix`
Also errors out when explicitly given options don't match, such as
`-pthread` is given with `-mthread-model single`.
Reviewers: dschuff, sbc100, tlively, sunfish
Subscribers: jgravelle-google, jfb, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D57874
llvm-svn: 353761
This is suggested by 3.3.9 of MSP430 EABI document.
We do allow user to manually enable frame pointer. GCC toolchain uses the same behavior.
Patch by Dmitry Mikushev!
Differential Revision: https://reviews.llvm.org/D56925
llvm-svn: 353212
Summary:
This adds support for new-PM plugin loading to clang. The option
`-fpass-plugin=` may be used to specify a dynamic shared object file
that adheres to the PassPlugin API.
Tested: created simple plugin that registers an EP callback; with optimization level > 0, the pass is run as expected.
Committed on behalf of Marco Elver
Differential Revision: https://reviews.llvm.org/D56935
llvm-svn: 352972
- fixes the test on macOS with LLVM_ENABLE_PIC=OFF
- together with D57343, gets the test to pass on Windows
- makes it run everywhere (it seems to just pass on Linux)
The main change is to pull out the resource directory computation into a
function shared by all 3 places that do it. In CIndexer.cpp, this now works no
matter if libclang is in lib/ or bin/ or statically linked to a binary in bin/.
Differential Revision: https://reviews.llvm.org/D57345
llvm-svn: 352803
..and use it to control that parts of CUDA compilation
that depend on the specific version of CUDA SDK.
This patch has a placeholder for a 'new launch API' support
which is in a separate patch. The list will be further
extended in the upcoming patch to support CUDA-10.1.
Differential Revision: https://reviews.llvm.org/D57487
llvm-svn: 352798
Append appropriate -rpath when using shared compiler-rt runtimes,
e.g. '-fsanitize=address -shared-libasan'. There's already a similar
logic in CommonArgs.cpp but it uses non-standard arch-suffixed
installation directory while we want our driver to work with standard
installation paths.
Differential Revision: https://reviews.llvm.org/D57303
llvm-svn: 352610
Introduce an option to request global visibility settings be applied to
declarations without a definition or an explicit visibility, rather than
the existing behavior of giving these default visibility. When the
visibility of all or most extern definitions are known this allows for
the same optimisations -fvisibility permits without updating source code
to annotate all declarations.
Differential Revision: https://reviews.llvm.org/D56868
llvm-svn: 352391
Relocatable code generation is meaningless on MSP430, as the platform is too small to use shared libraries.
Patch by Dmitry Mikushev!
Differential Revision: https://reviews.llvm.org/D56927
llvm-svn: 352181
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
These two options enable/disable emission of R_{MICRO}MIPS_JALR fixups along
with PIC calls. The linker may then try to turn PIC calls into direct jumps.
By default, these fixups do get emitted by the backend, use
'-mno-relax-pic-calls' to omit them.
Differential revision: https://reviews.llvm.org/D56878
llvm-svn: 351579
This is an initial implementation for msp430 toolchain including
-mmcu option support
-mhwmult options support
-integrated-as by default
The toolchain uses msp430-elf-as as a linker and supports msp430-gcc toolchain tree.
Patch by Kristina Bessonova!
Differential Revision: https://reviews.llvm.org/D56658
llvm-svn: 351228
This adds support for multilib paths for wasm32 targets, following
[Debian's Multiarch conventions], and also adds an experimental OS name in
order to test it.
[Debian's Multiarch conventions]: https://wiki.debian.org/Multiarch/
Differential Revision: https://reviews.llvm.org/D56553
llvm-svn: 351164
Summary:
After r327851, Driver::GetTemporaryPath will create the file rather than
just create a potientially unqine filename. If clang driver pass the
file as parameter as -object_path_lto, ld64 will pass it back to libLTO
as GeneratedObjectsDirectory, which is going to cause a LLVM ERROR if it
is not a directory.
Now during thinLTO, pass a temp directory path to linker instread.
rdar://problem/47194182
Reviewers: arphaman, dexonsmith
Reviewed By: arphaman
Subscribers: mehdi_amini, inglorion, jkorous, cfe-commits
Differential Revision: https://reviews.llvm.org/D56608
llvm-svn: 350970
Summary:
Adds a new -f[no]split-lto-unit flag that is disabled by default to
control module splitting during ThinLTO. It is automatically enabled
for -fsanitize=cfi and -fwhole-program-vtables.
The new EnableSplitLTOUnit codegen flag is passed down to llvm
via a new module flag of the same name.
Depends on D53890.
Reviewers: pcc
Subscribers: ormris, mehdi_amini, inglorion, eraman, steven_wu, dexonsmith, cfe-commits, llvm-commits
Differential Revision: https://reviews.llvm.org/D53891
llvm-svn: 350949
When clang is running on windows, /dev/null is not available. Use nul as empty input file instead.
Differential Revision: https://reviews.llvm.org/D56225
llvm-svn: 350885
Summary: Introduce a compiler flag for cases when the user knows that the collapsed loop counter can be safely represented using at most 32 bits. This will prevent the emission of expensive mathematical operations (such as the div operation) on the iteration variable using 64 bits where 32 bit operations are sufficient.
Reviewers: ABataev, caomhin
Reviewed By: ABataev
Subscribers: hfinkel, kkwli0, guansong, cfe-commits
Differential Revision: https://reviews.llvm.org/D55928
llvm-svn: 350758
Summary:
By using '..' instead of fs::parent_path.
The intention of the code was to go from 'path/to/clang/bin' to
'path/to/clang/include'. In most cases parent_path works, however it
would fail when clang is run as './clang'.
This was noticed in Chromium's bug tracker, see
https://bugs.chromium.org/p/chromium/issues/detail?id=919761
Reviewers: arphaman, thakis, EricWF
Reviewed By: arphaman, thakis
Subscribers: christof, cfe-commits
Differential Revision: https://reviews.llvm.org/D56446
llvm-svn: 350714
The problem is similar to D55986 but for threads: a process with the
interceptor hwasan library loaded might have some threads started by
instrumented libraries and some by uninstrumented libraries, and we
need to be able to run instrumented code on the latter.
The solution is to perform per-thread initialization lazily. If a
function needs to access shadow memory or add itself to the per-thread
ring buffer its prologue checks to see whether the value in the
sanitizer TLS slot is null, and if so it calls __hwasan_thread_enter
and reloads from the TLS slot. The runtime does the same thing if it
needs to access this data structure.
This change means that the code generator needs to know whether we
are targeting the interceptor runtime, since we don't want to pay
the cost of lazy initialization when targeting a platform with native
hwasan support. A flag -fsanitize-hwaddress-abi={interceptor,platform}
has been introduced for selecting the runtime ABI to target. The
default ABI is set to interceptor since it's assumed that it will
be more common that users will be compiling application code than
platform code.
Because we can no longer assume that the TLS slot is initialized,
the pthread_create interceptor is no longer necessary, so it has
been removed.
Ideally, lazy initialization should only cost one instruction in the
hot path, but at present the call may cause us to spill arguments
to the stack, which means more instructions in the hot path (or
theoretically in the cold path if the spills are moved with shrink
wrapping). With an appropriately chosen calling convention for
the per-thread initialization function (TODO) the hot path should
always need just one instruction and the cold path should need two
instructions with no spilling required.
Differential Revision: https://reviews.llvm.org/D56038
llvm-svn: 350429
The offload bundler action should not unbundle the input file types that does not match the action type. This fixes an issue where .so files are unbundled when the action type is object files.
llvm-svn: 350425
midl invokes the compiler on .idl files with /E. Before this change, we
would treat unrecognized inputs as object files. Now we pre-process to
stdout as expected. I checked that MSVC defines __cplusplus when invoked
this way, so treating the input as C++ seems like the right thing to do.
After this change, I was able to run midl like this with clang-cl:
$ midl -cpp_cmd clang-cl.exe foo.idl
Things worked for the example IDL file in the Microsoft documentation,
but beyond that, I don't know if this will work well.
Fixes PR40140
llvm-svn: 350072
Gentoo supports combining clang toolchain with GNU binutils, and many
users actually do that. As -faddrsig is not supported by GNU strip,
this results in a lot of warnings. Disable it by default and let users
enable it explicitly if they want it; with the intent of reevaluating
when the underlying feature becomes standarized.
See also: https://bugs.gentoo.org/667854
Differential Revision: https://reviews.llvm.org/D56047
llvm-svn: 350028
Add support for distinguishing plain Gentoo distribution, and a unit
test for it. This is going to be used to introduce distro-specific
customizations in the driver code; most notably, it is going to be used
to disable -faddrsig.
Differential Revision: https://reviews.llvm.org/D56024
llvm-svn: 350027
If an -analyzer-config is passed through -Xanalyzer, it is not found while
looking for -Xclang.
Additionally, don't emit -analyzer-config-compatibility-mode for *every*
-analyzer-config flag we encounter; one is enough.
https://reviews.llvm.org/D55823
rdar://problem/46504165
llvm-svn: 349866
Since r348038 we emit an error every time an -analyzer-config option is not
found. The driver, however, suppresses this error with another flag,
-analyzer-config-compatibility-mode, so backwards compatibility is maintained,
while analyzer developers still enjoy the new typo-free experience.
The backwards compatibility turns out to be still broken when the -analyze
action is not specified; it is still possible to specify -analyzer-config
in that case. This should be fixed now.
Patch by Kristóf Umann!
Differential Revision: https://reviews.llvm.org/D55823
rdar://problem/46504165
llvm-svn: 349824
Replace multiple comparisons of getOS() value with FreeBSD, NetBSD,
OpenBSD and DragonFly with matching isOS*BSD() methods. This should
improve the consistency of coding style without changing the behavior.
Direct getOS() comparisons were left whenever used in switch or switch-
like context.
Differential Revision: https://reviews.llvm.org/D55916
llvm-svn: 349752
NetBSD intends to support only reentrant interfaces in interceptors.
When -lpthread is used without _REENTRANT defined, things are
not guaranteed to work.
This is especially important for <stdio.h> and sanitization of
interfaces around FILE. Some APIs have alternative modes depending
on the _REENTRANT definition, and NetBSD intends to support sanitization
of the _REENTRANT ones.
Differential Revision: https://reviews.llvm.org/D55654
llvm-svn: 349650
Avoid passing -faddrsig by default on NetBSD. This platform is still
using old GNU binutils that crashes on executables containing those
sections.
Differential Revision: https://reviews.llvm.org/D55828
llvm-svn: 349647
NFC for targets other than PS4.
Respect -nostdlib and -nodefaultlibs when enabling asan or ubsan.
Differential Revision: https://reviews.llvm.org/D55712
llvm-svn: 349508
For targets where SEH exceptions are used by default (on MinGW,
only x86_64 so far), -munwind-tables are added automatically. If
-fseh-exeptions is enabled on a target where SEH exeptions are
availble but not enabled by default yet (aarch64), we need to
pass -munwind-tables if -fseh-exceptions was specified.
Differential Revision: https://reviews.llvm.org/D55749
llvm-svn: 349452
Summary:
Add an option to initialize automatic variables with either a pattern or with
zeroes. The default is still that automatic variables are uninitialized. Also
add attributes to request uninitialized on a per-variable basis, mainly to disable
initialization of large stack arrays when deemed too expensive.
This isn't meant to change the semantics of C and C++. Rather, it's meant to be
a last-resort when programmers inadvertently have some undefined behavior in
their code. This patch aims to make undefined behavior hurt less, which
security-minded people will be very happy about. Notably, this means that
there's no inadvertent information leak when:
- The compiler re-uses stack slots, and a value is used uninitialized.
- The compiler re-uses a register, and a value is used uninitialized.
- Stack structs / arrays / unions with padding are copied.
This patch only addresses stack and register information leaks. There's many
more infoleaks that we could address, and much more undefined behavior that
could be tamed. Let's keep this patch focused, and I'm happy to address related
issues elsewhere.
To keep the patch simple, only some `undef` is removed for now, see
`replaceUndef`. The padding-related infoleaks are therefore not all gone yet.
This will be addressed in a follow-up, mainly because addressing padding-related
leaks should be a stand-alone option which is implied by variable
initialization.
There are three options when it comes to automatic variable initialization:
0. Uninitialized
This is C and C++'s default. It's not changing. Depending on code
generation, a programmer who runs into undefined behavior by using an
uninialized automatic variable may observe any previous value (including
program secrets), or any value which the compiler saw fit to materialize on
the stack or in a register (this could be to synthesize an immediate, to
refer to code or data locations, to generate cookies, etc).
1. Pattern initialization
This is the recommended initialization approach. Pattern initialization's
goal is to initialize automatic variables with values which will likely
transform logic bugs into crashes down the line, are easily recognizable in
a crash dump, without being values which programmers can rely on for useful
program semantics. At the same time, pattern initialization tries to
generate code which will optimize well. You'll find the following details in
`patternFor`:
- Integers are initialized with repeated 0xAA bytes (infinite scream).
- Vectors of integers are also initialized with infinite scream.
- Pointers are initialized with infinite scream on 64-bit platforms because
it's an unmappable pointer value on architectures I'm aware of. Pointers
are initialize to 0x000000AA (small scream) on 32-bit platforms because
32-bit platforms don't consistently offer unmappable pages. When they do
it's usually the zero page. As people try this out, I expect that we'll
want to allow different platforms to customize this, let's do so later.
- Vectors of pointers are initialized the same way pointers are.
- Floating point values and vectors are initialized with a negative quiet
NaN with repeated 0xFF payload (e.g. 0xffffffff and 0xffffffffffffffff).
NaNs are nice (here, anways) because they propagate on arithmetic, making
it more likely that entire computations become NaN when a single
uninitialized value sneaks in.
- Arrays are initialized to their homogeneous elements' initialization
value, repeated. Stack-based Variable-Length Arrays (VLAs) are
runtime-initialized to the allocated size (no effort is made for negative
size, but zero-sized VLAs are untouched even if technically undefined).
- Structs are initialized to their heterogeneous element's initialization
values. Zero-size structs are initialized as 0xAA since they're allocated
a single byte.
- Unions are initialized using the initialization for the largest member of
the union.
Expect the values used for pattern initialization to change over time, as we
refine heuristics (both for performance and security). The goal is truly to
avoid injecting semantics into undefined behavior, and we should be
comfortable changing these values when there's a worthwhile point in doing
so.
Why so much infinite scream? Repeated byte patterns tend to be easy to
synthesize on most architectures, and otherwise memset is usually very
efficient. For values which aren't entirely repeated byte patterns, LLVM
will often generate code which does memset + a few stores.
2. Zero initialization
Zero initialize all values. This has the unfortunate side-effect of
providing semantics to otherwise undefined behavior, programs therefore
might start to rely on this behavior, and that's sad. However, some
programmers believe that pattern initialization is too expensive for them,
and data might show that they're right. The only way to make these
programmers wrong is to offer zero-initialization as an option, figure out
where they are right, and optimize the compiler into submission. Until the
compiler provides acceptable performance for all security-minded code, zero
initialization is a useful (if blunt) tool.
I've been asked for a fourth initialization option: user-provided byte value.
This might be useful, and can easily be added later.
Why is an out-of band initialization mecanism desired? We could instead use
-Wuninitialized! Indeed we could, but then we're forcing the programmer to
provide semantics for something which doesn't actually have any (it's
uninitialized!). It's then unclear whether `int derp = 0;` lends meaning to `0`,
or whether it's just there to shut that warning up. It's also way easier to use
a compiler flag than it is to manually and intelligently initialize all values
in a program.
Why not just rely on static analysis? Because it cannot reason about all dynamic
code paths effectively, and it has false positives. It's a great tool, could get
even better, but it's simply incapable of catching all uses of uninitialized
values.
Why not just rely on memory sanitizer? Because it's not universally available,
has a 3x performance cost, and shouldn't be deployed in production. Again, it's
a great tool, it'll find the dynamic uses of uninitialized variables that your
test coverage hits, but it won't find the ones that you encounter in production.
What's the performance like? Not too bad! Previous publications [0] have cited
2.7 to 4.5% averages. We've commmitted a few patches over the last few months to
address specific regressions, both in code size and performance. In all cases,
the optimizations are generally useful, but variable initialization benefits
from them a lot more than regular code does. We've got a handful of other
optimizations in mind, but the code is in good enough shape and has found enough
latent issues that it's a good time to get the change reviewed, checked in, and
have others kick the tires. We'll continue reducing overheads as we try this out
on diverse codebases.
Is it a good idea? Security-minded folks think so, and apparently so does the
Microsoft Visual Studio team [1] who say "Between 2017 and mid 2018, this
feature would have killed 49 MSRC cases that involved uninitialized struct data
leaking across a trust boundary. It would have also mitigated a number of bugs
involving uninitialized struct data being used directly.". They seem to use pure
zero initialization, and claim to have taken the overheads down to within noise.
Don't just trust Microsoft though, here's another relevant person asking for
this [2]. It's been proposed for GCC [3] and LLVM [4] before.
What are the caveats? A few!
- Variables declared in unreachable code, and used later, aren't initialized.
This goto, Duff's device, other objectionable uses of switch. This should
instead be a hard-error in any serious codebase.
- Volatile stack variables are still weird. That's pre-existing, it's really
the language's fault and this patch keeps it weird. We should deprecate
volatile [5].
- As noted above, padding isn't fully handled yet.
I don't think these caveats make the patch untenable because they can be
addressed separately.
Should this be on by default? Maybe, in some circumstances. It's a conversation
we can have when we've tried it out sufficiently, and we're confident that we've
eliminated enough of the overheads that most codebases would want to opt-in.
Let's keep our precious undefined behavior until that point in time.
How do I use it:
1. On the command-line:
-ftrivial-auto-var-init=uninitialized (the default)
-ftrivial-auto-var-init=pattern
-ftrivial-auto-var-init=zero -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
2. Using an attribute:
int dont_initialize_me __attribute((uninitialized));
[0]: https://users.elis.ugent.be/~jsartor/researchDocs/OOPSLA2011Zero-submit.pdf
[1]: https://twitter.com/JosephBialek/status/1062774315098112001
[2]: https://outflux.net/slides/2018/lss/danger.pdf
[3]: https://gcc.gnu.org/ml/gcc-patches/2014-06/msg00615.html
[4]: 776a0955ef
[5]: http://wg21.link/p1152
I've also posted an RFC to cfe-dev: http://lists.llvm.org/pipermail/cfe-dev/2018-November/060172.html
<rdar://problem/39131435>
Reviewers: pcc, kcc, rsmith
Subscribers: JDevlieghere, jkorous, dexonsmith, cfe-commits
Differential Revision: https://reviews.llvm.org/D54604
llvm-svn: 349442
Summary:
The msvc exception specifier for noexcept function types has changed
from the prior default of "Z" to "_E" if the function cannot throw when
compiling with /std:C++17.
Patch by Zachary Henkel!
Reviewers: zturner, rnk
Reviewed By: rnk
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D55685
llvm-svn: 349414
is not specified
The -target option allows the user to specify the build target using LLVM
triple. The triple includes the arch, and so the -arch option is redundant.
This should work just as well without the -arch. However, the driver has a bug
in which it doesn't target the "Cyclone" CPU for darwin if -target is used
without -arch. This commit fixes this issue.
rdar://46743182
Differential Revision: https://reviews.llvm.org/D55731
llvm-svn: 349382
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
pass in the -target-sdk-version to the compiler and backend
This commit adds support for reading the SDKSettings.json file in the Darwin
driver. This file is used by the driver to determine the SDK's version, and it
uses that information to pass it down to the compiler using the new
-target-sdk-version= option. This option is then used to set the appropriate
SDK Version module metadata introduced in r349119.
Note: I had to adjust the two ast tests as the SDKROOT environment variable
on macOS caused SDK version to be picked up for the compilation of source file
but not the AST.
rdar://45774000
Differential Revision: https://reviews.llvm.org/D55673
llvm-svn: 349380
Implement options in clang to enable recording the driver command-line
in an ELF section.
Implement a new special named metadata, llvm.commandline, to support
frontends embedding their command-line options in IR/ASM/ELF.
This differs from the GCC implementation in some key ways:
* In GCC there is only one command-line possible per compilation-unit,
in LLVM it mirrors llvm.ident and multiple are allowed.
* In GCC individual options are separated by NULL bytes, in LLVM entire
command-lines are separated by NULL bytes. The advantage of the GCC
approach is to clearly delineate options in the face of embedded
spaces. The advantage of the LLVM approach is to support merging
multiple command-lines unambiguously, while handling embedded spaces
with escaping.
Differential Revision: https://reviews.llvm.org/D54487
Clang Differential Revision: https://reviews.llvm.org/D54489
llvm-svn: 349155
Summary:
Added support for the -gline-directives-only option + fixed logic of the
debug info for CUDA devices. If optimization level is O0, then options
--[no-]cuda-noopt-device-debug do not affect the debug info level. If
the optimization level is >O0, debug info options are used +
--no-cuda-noopt-device-debug is used or no --cuda-noopt-device-debug is
used, the optimization level for the device code is kept and the
emission of the debug directives is used.
If the opt level is > O0, debug info is requested +
--cuda-noopt-device-debug option is used, the optimization is disabled
for the device code + required debug info is emitted.
Reviewers: tra, echristo
Subscribers: aprantl, guansong, JDevlieghere, cfe-commits
Differential Revision: https://reviews.llvm.org/D51554
llvm-svn: 348930
It is faster to directly call the ObjC runtime for methods such as alloc/allocWithZone instead of sending a message to those functions.
This patch adds support for converting messages to alloc/allocWithZone to their equivalent runtime calls.
Tests included for the positive case of applying this transformation, negative tests that we ensure we only convert "alloc" to objc_alloc, not "alloc2", and also a driver test to ensure we enable this only for supported runtime versions.
Reviewed By: rjmccall
https://reviews.llvm.org/D55349
llvm-svn: 348687
The flag -fdebug-compilation-dir is useful to make generated .o files
independent of the path of the build directory, without making the compile
command-line dependent on the path of the build directory, like
-fdebug-prefix-map requires. This change makes it so that the driver can
forward the flag to -cc1as, like it already can for -cc1. We might want to
consider making -fdebug-compilation-dir a driver flag in a follow-up.
(Since -fdebug-compilation-dir defaults to PWD, it's already possible to get
this effect by setting PWD, but explicit compiler flags are better than env
vars, because e.g. ninja tracks command lines and reruns commands that change.)
Somewhat related to PR14625.
Differential Revision: https://reviews.llvm.org/D55377
llvm-svn: 348515
Summary:
The intention is to make the tools replaying compilations from 'compile_commands.json'
(clang-tidy, clangd, etc.) find the same standard library as the original compiler
specified in 'compile_commands.json'.
Previously, the library detection logic was in the frontend (InitHeaderSearch.cpp) and relied
on the value of resource dir as an approximation of the compiler install dir. The new logic
uses the actual compiler install dir and is performed in the driver. This is consistent with
the C++ standard library detection on other platforms and allows to override the resource dir
in the tools using the compile_commands.json without altering the
standard library detection mechanism. The tools have to override the resource dir to make sure
they use a consistent version of the builtin headers.
There is still logic in InitHeaderSearch that attemps to add the absolute includes for the
the C++ standard library, so we keep passing the -stdlib=libc++ from the driver to the frontend
via cc1 args to avoid breaking that. In the long run, we should move this logic to the driver too,
but it could potentially break the library detection on other systems, so we don't tackle it in this
patch to keep its scope manageable.
This is a second attempt to fix the issue, first one was commited in r346652 and reverted in r346675.
The original fix relied on an ad-hoc propagation (bypassing the cc1 flags) of the install dir from the
driver to the frontend's HeaderSearchOptions. Unsurpisingly, the propagation was incomplete, it broke
the libc++ detection in clang itself, which caused LLDB tests to break.
The LLDB tests pass with new fix.
Reviewers: JDevlieghere, arphaman, EricWF
Reviewed By: arphaman
Subscribers: mclow.lists, ldionne, dexonsmith, ioeric, christof, kadircet, cfe-commits
Differential Revision: https://reviews.llvm.org/D54630
llvm-svn: 348365
This is an updated version of the D54576, which was reverted.
Problem was that SplitDebugName calls the InputInfo::getFilename
which asserts if InputInfo given is not of type Filename:
const char *getFilename() const {
assert(isFilename() && "Invalid accessor.");
return Data.Filename;
}
At the same time at that point, it can be of type Nothing and
we need to use getBaseInput(), like original code did.
Differential revision: https://reviews.llvm.org/D55006
llvm-svn: 348352
When debugging a boost build with a modified
version of Clang, I discovered that the PTH implementation
stores TokenKind in 8 bits. However, we currently have 368
TokenKinds.
The result is that the value gets truncated and the wrong token
gets picked up when including PTH files. It seems that this will
go wrong every time someone uses a token that uses the 9th bit.
Upon asking on IRC, it was brought up that this was a highly
experimental features that was considered a failure. I discovered
via googling that BoostBuild (mostly Boost.Math) is the only user of
this
feature, using the CC1 flag directly. I believe that this can be
transferred over to normal PCH with minimal effort:
https://github.com/boostorg/build/issues/367
Based on advice on IRC and research showing that this is a nearly
completely unused feature, this patch removes it entirely.
Note: I considered leaving the build-flags in place and making them
emit an error/warning, however since I've basically identified and
warned the only user, it seemed better to just remove them.
Differential Revision: https://reviews.llvm.org/D54547
Change-Id: If32744275ef1f585357bd6c1c813d96973c4d8d9
llvm-svn: 348266
When the global new and delete operators aren't declared, Clang
provides and implicit declaration, but this declaration currently
always uses the default visibility. This is a problem when the
C++ library itself is being built with non-default visibility because
the implicit declaration will force the new and delete operators to
have the default visibility unlike the rest of the library.
The existing workaround is to use assembly to enforce the visiblity:
https://fuchsia.googlesource.com/zircon/+/master/system/ulib/zxcpp/new.cpp#108
but that solution is not always available, e.g. in the case of of
libFuzzer which is using an internal version of libc++ that's also built
with -fvisibility=hidden where the existing behavior is causing issues.
This change introduces a new option -fvisibility-global-new-delete-hidden
which makes the implicit declaration of the global new and delete
operators hidden.
Differential Revision: https://reviews.llvm.org/D53787
llvm-svn: 348234
Make sure that symbols needed to implement runtime support for gcov are
exported when using an export list on Darwin.
Without the clang driver exporting these symbols, the linker hides them,
resulting in tapi verification failures.
rdar://45944768
Differential Revision: https://reviews.llvm.org/D55151
llvm-svn: 348187
Summary:
This patch passes an option '-z max-page-size=4096' to lld through clang driver.
This is for Android on Aarch64 target.
The lld default page size is too large for Aarch64, which produces larger .so files and images for arm64 device targets.
In this patch we set default page size to 4KB for Android Aarch64 targets instead.
Reviewers: srhines, danalbert, ruiu, chh, peter.smith
Reviewed By: srhines
Subscribers: javed.absar, kristof.beyls, cfe-commits, george.burgess.iv, llozano
Differential Revision: https://reviews.llvm.org/D55029
llvm-svn: 347897
This adds Hurd toolchain support to Clang's driver in addition
to handling translating the triple from Hurd-compatible form to
the actual triple registered in LLVM.
(Phabricator was stripping the empty files from the patch so I
manually created them)
Patch by sthibaul (Samuel Thibault)
Differential Revision: https://reviews.llvm.org/D54379
llvm-svn: 347833
Summary:
Linux toolchain accidentally added "-u__llvm_runtime_variable" when "-fprofile-arcs -ftest-coverage", this is not added when "--coverage" option is used.
Using "-u__llvm_runtime_variable" generates an empty default.profraw file while an application built with "-fprofile-arcs -ftest-coverage" is running.
Reviewers: calixte, marco-c, sylvestre.ledru
Reviewed By: marco-c
Subscribers: vsk, cfe-commits
Differential Revision: https://reviews.llvm.org/D54195
llvm-svn: 347677
This reverts commit r347035 as it introduced assertion failures under
certain conditions. More information can be found here:
https://reviews.llvm.org/rL347035
llvm-svn: 347676
Summary:
-mno-speculative-load-hardening isn't a cc1 option, therefore,
before this change:
clang -mno-speculative-load-hardening hello.cpp
would have the following error:
error: unknown argument: '-mno-speculative-load-hardening'
This change will only ever forward -mspeculative-load-hardening
which is a CC1 option based on which flag was passed to clang.
Also added a test that uses this option that fails if an error like the
above is ever thrown.
Thank you ericwf for help debugging and fixing this error.
Reviewers: chandlerc, EricWF
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D54763
llvm-svn: 347582
This reverts commit r347413: older versions of ld.gold that are used
by Android don't support --push/pop-state which broke sanitizer bots.
llvm-svn: 347430
Sanitizer runtime link deps handling passes --no-as-needed because of
PR15823, but it never undoes it and this flag may affect other libraries
that come later on the link line. To avoid this, wrap Sanitizer link
deps in --push/pop-state.
Differential Revision: https://reviews.llvm.org/D54805
llvm-svn: 347413
Even though these deps weren't needed, this makes Fuchsia driver
better match other drivers, and it may be necessary when trying to
use different C libraries on Fuchsia.
Differential Revision: https://reviews.llvm.org/D54741
llvm-svn: 347378
Because SCS relies on system-provided runtime support, we can use it
together with any other sanitizer simply by linking the runtime for
the other sanitizer.
Differential Revision: https://reviews.llvm.org/D54735
llvm-svn: 347282
Fangrui Song