There is currently an EPERM error when a regular user executes `llvm-objcopy a.o /dev/null`.
Worse, root can even change the mode bits of /dev/null.
Fix it by checking if the output file is special.
A new overload of llvm::sys::fs::setPermissions with FD as the parameter
is added. Users should provide `perm & ~umask` as the parameter if they
intend to respect umask.
The existing overload of llvm::sys::fs::setPermissions may be deleted if
we can find an implementation of fchmod() on Windows. fchmod() is
usually better than chmod() because it saves syscalls and can avoid race
condition.
Reviewed By: jakehehrlich, jhenderson
Differential Revision: https://reviews.llvm.org/D64236
llvm-svn: 365753
Summary:
As of binutils 2.32, ld has a bogus TLS relaxation error when the GD/LD
code sequence using R_X86_64_GOTPCREL (instead of R_X86_64_GOTPCRELX) is
attempted to be relaxed to IE/LE (binutils PR24784). gold and lld are good.
In gcc/config/i386/i386.md, there is a configure-time check of as/ld
support and the GOT relaxation will not be used if as/ld doesn't support
it:
if (flag_plt || !HAVE_AS_IX86_TLS_GET_ADDR_GOT)
return "call\t%P2";
return "call\t{*%p2@GOT(%1)|[DWORD PTR %p2@GOT[%1]]}";
In clang, -DENABLE_X86_RELAX_RELOCATIONS=OFF is the default. The ld.bfd
bogus error can be reproduced with:
thread_local int a;
int main() { return a; }
clang -fno-plt -fpic a.cc -fuse-ld=bfd
GOTPCRELX gained relative good support in 2016, which is considered
relatively new. It is even difficult to conditionally default to
-DENABLE_X86_RELAX_RELOCATIONS=ON due to cross compilation reasons. So
work around the ld.bfd bug by only using GOT when GOTPCRELX is enabled.
Reviewers: dalias, hjl.tools, nikic, rnk
Reviewed By: nikic
Subscribers: llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64304
llvm-svn: 365752
Currently invalid bitcode files can cause a crash, when OpNum exceeds
the number of elements in Record, like in the attached bitcode file.
The test case was generated by clusterfuzz: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=15698
Reviewers: t.p.northover, thegameg, jfb
Reviewed By: jfb
Differential Revision: https://reviews.llvm.org/D64507
llvm-svn: 365750
This patch addresses a couple of problems:
1) The maximum supported offset of LE is -4094.
2) The offset of WLS also needs to be checked, this uses a
maximum positive offset of 4094.
The use of BasicBlockUtils has been changed because the block offsets
weren't being initialised, but the isBBInRange checks both positive
and negative offsets.
ARMISelLowering has been tweaked because the test case presented
another pattern that we weren't supporting.
llvm-svn: 365749
The VQDMLAH.U8, VQDMLAH.U16 and VQDMLAH.U32 instructions don't
actually exist: the Armv8.1-M architecture spec only lists signed
forms of that instruction. The unsigned ones were added in error: they
existed in an early draft of the spec, but they were removed before
the public version, and we missed that particular spec change.
Also affects the variant forms VQDMLASH, VQRDMLAH and VQRDMLASH.
Reviewers: miyuki
Subscribers: javed.absar, kristof.beyls, hiraditya, dmgreen, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64502
llvm-svn: 365747
Skip copies between virtual registers during search for UseDefs
and DefUses.
Since each operand has one def search for UseDefs is straightforward.
But since operand can have many uses, we have to check all uses of
each copy we traverse during search for DefUses.
Differential Revision: https://reviews.llvm.org/D64486
llvm-svn: 365744
When one of the uses/defs of ambiguous instruction is also ambiguous
visit it recursively and search its uses/defs for instruction with
only one mapping available.
When all instruction in a chain are ambiguous arbitrary mapping can
be selected. For s64 operands in ambiguous chain fprb is selected since
it results in less instructions then having to narrow scalar s64 to s32.
For s32 both gprb and fprb result in same number of instructions and
gprb is selected like a general purpose option.
At the moment we always avoid cross register bank copies.
TODO: Implement a model for costs calculations of different mappings
on same instruction and cross bank copies. Allow cross bank copies
when appropriate according to cost model.
Differential Revision: https://reviews.llvm.org/D64485
llvm-svn: 365743
This reverts r365675 (git commit 43d75f977853c3ec891a440c362b2df183a211b5)
The patch causes a crash in SupportTests (CommandLineTest.AliasesWithArguments).
llvm-svn: 365742
Two functional changes have been made here:
- Now search up from any add instruction to find the chains of
operations that we may turn into a smlad. This allows the
generation of a smlad which doesn't accumulate into a phi.
- The search function has been corrected to stop it falsely searching
up through an invalid path.
The bulk of the changes have been making the Reduction struct a class
and making it more C++y with getters and setters.
Differential Revision: https://reviews.llvm.org/D61780
llvm-svn: 365740
Without this gcc 7.4.0 complains with
../unittests/Analysis/ValueTrackingTest.cpp:937:66: error: ISO C++11 requires at least one argument for the "..." in a variadic macro [-Werror]
::testing::ValuesIn(IsBytewiseValueTests));
^
llvm-svn: 365738
Summary:
Wasm does not currently support `llvm.clear_cache` intrinsic, and this
prints a proper error message instead of segfault.
Reviewers: dschuff, sbc100, sunfish
Subscribers: jgravelle-google, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64322
llvm-svn: 365731
This patch replaces the three almost identical "strip & accumulate"
implementations for constant pointer offsets with a single one,
combining the respective functionalities. The old interfaces are kept
for now.
Differential Revision: https://reviews.llvm.org/D64468
llvm-svn: 365723
We are about to add enum attributes with AttrKind numbers >= 63. This
means we cannot use AttrKind #63 to test for an invalid attribute number
in the RAW format anymore. This patch changes the number of an invalid
attribute to #255. There is no change to the character of the tests.
Differential Revision: https://reviews.llvm.org/D64531
llvm-svn: 365722
We use the functions that convert to three address to do the
conversion, but changing an 8 or 16 bit will cause it to create
a virtual register. This can't be done after register allocation
where this pass runs.
I've switched the pass completely to a white list of instructions
that can be converted to LEA instead of a blacklist that was
incorrect. This will avoid surprises if we enhance the three
address conversion function to include additional instructions
in the future.
Fixes PR42565.
llvm-svn: 365720
This reverts r365193 (git commit 194f16b3548bcb23a7f0fd638778ed72edd18d37)
This patch doesn't work with binaries built w/ `--emit-relocs`, e.g.
```
$ echo 'int main() { return 0; }' | clang -Wl,--emit-relocs -x c - -o foo && llvm-objcopy --strip-unneeded foo
llvm-objcopy: error: 'foo': not stripping symbol '__gmon_start__' because it is named in a relocation
```
llvm-svn: 365712
If we have:
R = sub X, Y
P = cmp Y, X
...then flipping the operands in the compare instruction can allow using a subtract that sets compare flags.
Motivated by diffs in D58875 - not sure if this changes anything there,
but this seems like a good thing independent of that.
There's a more involved version of this transform already in IR (in instcombine
although that seems misplaced to me) - see "swapMayExposeCSEOpportunities()".
Differential Revision: https://reviews.llvm.org/D63958
llvm-svn: 365711
Summary:
We will need to handle IntToPtr which I will submit in a separate patch as it's
not going to be NFC.
Reviewers: eugenis, pcc
Reviewed By: eugenis
Subscribers: hiraditya, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D63940
llvm-svn: 365709
Unfortunately subo formation in CGP prevents obvious ways of
testing this.
But we already have BLSI in here and the flag behavior is
well understood.
Might become more useful if we improve PR42571.
llvm-svn: 365702
Summary: llvm/IR/GlobalValue.h can't be included in MC, that creates a circular dependency between MC and IR libraries. This circular dependency is causing an issue for build system that enforce layering.
Author: Xiangling_L
Reviewers: sfertile, jasonliu, hubert.reinterpretcast, gribozavr
Reviewed By: gribozavr
Subscribers: wuzish, nemanjai, hiraditya, kbarton, MaskRay, jsji, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64445
llvm-svn: 365701
Since we have distinct types for pointers and scalars, G_INTTOPTRs can sometimes
obstruct attempts to find constant source values. These usually come about when
try to do some kind of null pointer check. Teaching getConstantVRegValWithLookThrough
about this operation allows the CBZ/CBNZ optimization to catch more cases.
This change also improves the case where we can't find a constant source at all.
Previously we would emit a cmp, cset and tbnz for that. Now we try to just emit
a cmp and conditional branch, saving an instruction.
The cumulative code size improvement of this change plus D64354 is 5.5% geomean
on arm64 CTMark -O0.
Differential Revision: https://reviews.llvm.org/D64377
llvm-svn: 365690
Some minor cleanup.
This function in Utils does the same thing as `findMIFromReg`. It also looks
through copies, which `findMIFromReg` didn't.
Delete `findMIFromReg` and use `getOpcodeDef` instead. This only happens in
`tryOptVectorDup` right now.
Update opt-shuffle-splat to show that we can look through the copies now, too.
Differential Revision: https://reviews.llvm.org/D64520
llvm-svn: 365684
There are a few places where we walk over copies throughout
AArch64InstructionSelector.cpp. In Utils, there's a function that does exactly
this which we can use instead.
Note that the utility function works with the case where we run into a COPY
from a physical register. We've run into bugs with this a couple times, so using
it should defend us from similar future bugs.
Also update opt-fold-compare.mir to show that we still handle physical registers
properly.
Differential Revision: https://reviews.llvm.org/D64513
llvm-svn: 365683
Summary: Unsafe does not map well alone for each of these three cases as it is missing NoNan context when accessed directly with clang. I have migrated the fold guards to reflect the expectations of handing nan and zero contexts directly (NoNan, NSZ) and some tests with it. Unsafe does include NSZ, however there is already precedent for using the target option directly to reflect that context.
Reviewers: spatel, wristow, hfinkel, craig.topper, arsenm
Reviewed By: arsenm
Subscribers: michele.scandale, wdng, javed.absar
Differential Revision: https://reviews.llvm.org/D64450
llvm-svn: 365679
Rework the TTI cache and software prefetching APIs to prepare for the
introduction of a general system model. Changes include:
- Marking existing interfaces const and/or override as appropriate
- Adding comments
- Adding BasicTTIImpl interfaces that delegate to a subtarget
implementation
- Adding a default "no information" subtarget implementation
Only a handful of targets use these interfaces currently: AArch64,
Hexagon, PPC and SystemZ. AArch64 already has a custom subtarget
implementation, so its custom TTI implementation is migrated to use
the new facilities in BasicTTIImpl to invoke its custom subtarget
implementation. The custom TTI implementations continue to exist for
the other targets with this change. They are not moved over to
subtarget-based implementations.
The end goal is to have the default subtarget implementation defer to
the system model defined by the target. With this change, the default
subtarget implementation essentially returns "no information" for
these interfaces. None of the existing users of TTI will hit that
implementation because they define their own custom TTI
implementations and won't use the BasicTTIImpl implementations.
Once system models are in place for the targets that use these
interfaces, their custom TTI implementations can be removed.
Differential Revision: https://reviews.llvm.org/D63614
llvm-svn: 365676
Previously reverted in 364141 due to buildbot breakage, and fixed here
by making GeneralCategory global a ManagedStatic.
Summary:
This change processes `OptionCategory`s and `SubCommand`s as they
are seen instead of caching them in the Option class and processing
them later. Doing so simplifies the work needed to be done by the Global
parser and significantly reduces the size of the Option class to a mere 64
bytes.
Removing the `OptionCategory` cache saved 24 bytes, and removing
the `SubCommand` cache saved an additional 48 bytes, for a total of a
72 byte reduction.
Reviewed By: serge-sans-paille
Tags: #llvm, #clang
Differential Revision: https://reviews.llvm.org/D62105
llvm-svn: 365675
Summary:
The map kept in loop rotate is used for instruction remapping, in order
to simplify the clones of instructions. Thus, if an instruction can be
simplified, its simplified value is placed in the map, even when the
clone is added to the IR. MemorySSA in contrast needs to know about that
clone, so it can add an access for it.
To resolve this: keep a different map for MemorySSA.
Reviewers: george.burgess.iv
Subscribers: jlebar, Prazek, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D63680
llvm-svn: 365672
LLJITBuilder now has a setCompileFunctionCreator method which can be used to
construct a CompileFunction for the LLJIT instance being created. The motivating
use-case for this is supporting ObjectCaches, which can now be set up at
compile-function construction time. To demonstrate this an example project,
LLJITWithObjectCache, is included.
llvm-svn: 365671
