I think we assume poison, not undef, for certain transforms we
currently do. In any case, we should clarify the language here.
(This sort of conversion is undefined behavior according to the C
and C++ standards. And in practice, hardware implementations handle
overflow inconsistently, so it would be difficult to define the
result here.)
Differential Revision: https://reviews.llvm.org/D47851
llvm-svn: 334326
We need to clarify the language here. I think poison makes more sense
than undef, since it's an undefined operation rather than uninitialized
memory. I don't think anything depends on the difference at the moment,
though.
Differential Revision: https://reviews.llvm.org/D47859
llvm-svn: 334325
It looks like this got left in by accident in r289794; I can't think of
any reason this check would be necessary. (Maybe it was meant to be a
check that the AND has one use? But we check that a few lines earlier.)
Differential Revision: https://reviews.llvm.org/D47921
llvm-svn: 334322
An expression like
(zext i2 {(trunc i32 (1 + %B) to i2),+,1}<%while.body> to i32)
will become zero exactly when the nested value becomes zero in its type.
Strip injective operations from the input value in howFarToZero to make
the value simpler.
Differential Revision: https://reviews.llvm.org/D47951
llvm-svn: 334318
Summary:
Move the corresponding tests to the common folder (as all of the
sanitizer allocators will support this feature soon) and add the checks
specific to aligned_alloc to ASan and LSan allocators.
Reviewers: vitalybuka
Subscribers: srhines, kubamracek, delcypher, #sanitizers, llvm-commits
Differential Revision: https://reviews.llvm.org/D47924
llvm-svn: 334316
Summary:
If we can use comdats, then we can make it so that the global metadata
is thrown away if the prevailing definition of the global was
uninstrumented. I have only tested this on COFF targets, but in theory,
there is no reason that we cannot also do this for ELF.
This will allow us to re-enable string merging with ASan on Windows,
reducing the binary size cost of ASan on Windows.
Reviewers: eugenis, vitalybuka
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D47841
llvm-svn: 334313
These builtins are all handled by CGBuiltin.cpp so it doesn't much matter what the immediate type is, but int matches the intrinsic spec.
llvm-svn: 334310
Extension to D46954 (PR37426), this patch adds support for v8i16/v16i16 rotations in a similar manner - the conversion of the shift/rotate amount to a multiplication factor and the use of PMULLW to shift left and PMULHUW (ISD::MULHU) to shift the wrapped bits back around to be ORd together.
Differential Revision: https://reviews.llvm.org/D47822
llvm-svn: 334309
Summary: This patch originated from D46562 and is a proper subset, with some issues addressed for fsub.
Reviewers: spatel, hfinkel, wristow, arsenm
Reviewed By: spatel
Subscribers: wdng
Differential Revision: https://reviews.llvm.org/D47910
llvm-svn: 334306
This patch moves the recipe-creation functions out of
LoopVectorizationPlanner, which should do the high-level
orchestration of the transformations.
Reviewers: dcaballe, rengolin, hsaito, Ayal
Reviewed By: dcaballe
Differential Revision: https://reviews.llvm.org/D47595
llvm-svn: 334305
As detailed on Agner's Microarchitecture doc (21.8 AMD Bobcat and Jaguar pipeline - Dependency-breaking instructions), these instructions are dependency breaking and fast-path zero the destination register (and appropriate EFLAGS bits).
llvm-svn: 334303
Same fix as rL334110: I noticed while working on zero-idiom + dependency-breaking support (PR36671) that most of our binary instruction schedule tests were reusing the same src registers, which would cause the tests to fail once we enable scalar zero-idiom support on btver2.
llvm-svn: 334302
AMDGPU inline assembler support i16, half and i128 typed variables in constraints, but they were reported as error.
Needed to fix https://github.com/RadeonOpenCompute/ROCm/issues/341,
e.g. to be able to load with global_load_dwordx4 to a 128bit integer variable
Differential Revision: https://reviews.llvm.org/D44920
llvm-svn: 334301
Summary:
`%ret = add nuw i8 %x, C`
From [[ https://llvm.org/docs/LangRef.html#add-instruction | langref ]]:
nuw and nsw stand for “No Unsigned Wrap” and “No Signed Wrap”,
respectively. If the nuw and/or nsw keywords are present,
the result value of the add is a poison value if unsigned
and/or signed overflow, respectively, occurs.
So if `C` is `-1`, `%x` can only be `0`, and the result is always `-1`.
I'm not sure we want to use `KnownBits`/`LVI` here, because there is
exactly one possible value (all bits set, `-1`), so some other pass
should take care of replacing the known-all-ones with constant `-1`.
The `test/Transforms/InstCombine/set-lowbits-mask-canonicalize.ll` change *is* confusing.
What happening is, before this: (omitting `nuw` for simplicity)
1. First, InstCombine D47428/rL334127 folds `shl i32 1, %NBits`) to `shl nuw i32 -1, %NBits`
2. Then, InstSimplify D47883/rL334222 folds `shl nuw i32 -1, %NBits` to `-1`,
3. `-1` is inverted to `0`.
But now:
1. *This* InstSimplify fold `%ret = add nuw i32 %setbit, -1` -> `-1` happens first,
before InstCombine D47428/rL334127 fold could happen.
Thus we now end up with the opposite constant,
and it is all good: https://rise4fun.com/Alive/OA9https://rise4fun.com/Alive/sldC
Was mentioned in D47428 review.
Follow-up for D47883.
Reviewers: spatel, craig.topper
Reviewed By: spatel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D47908
llvm-svn: 334298
Summary:
The function `llvm::sys::commandLineFitsWithinSystemLimits` appears to be overestimating the system limits. This issue was discovered while attempting to enable response files in the Swift compiler. When the compiler submits its frontend jobs, those jobs are subjected to the system limits on command line length. `commandLineFitsWithinSystemLimits` is used to determine if the job's arguments need to be wrapped in a response file. There are some cases where the argument size for the job passes `commandLineFitsWithinSystemLimits`, but actually exceeds the real system limit, and the job fails.
`clang` also uses this function to decide whether or not to wrap it's job arguments in response files. See: https://github.com/llvm-mirror/clang/blob/master/lib/Driver/Driver.cpp#L1341. Clang will also fail for response files who's size falls within a certain range. I wrote a script that should find a failure point for `clang++`. All that is needed to run it is Python 2.7, and a simple "hello world" program for `test.cc`. It should run on Linux and on macOS. The script is available here: https://gist.github.com/dabelknap/71bd083cd06b91c5b3cef6a7f4d3d427. When it hits a failure point, you should see a `clang: error: unable to execute command: posix_spawn failed: Argument list too long`.
The proposed solution is to mirror the behavior of `xargs` in `commandLinefitsWithinSystemLimits`. `xargs` defaults to 128k for the command line length size (See: https://fossies.org/dox/findutils-4.6.0/buildcmd_8c_source.html#l00551). It adjusts this depending on the value of `ARG_MAX`.
Reviewers: alexfh
Reviewed By: alexfh
Subscribers: llvm-commits
Tags: #clang
Patch by Austin Belknap!
Differential Revision: https://reviews.llvm.org/D47795
llvm-svn: 334295
NFC here, this just raises some platform specific ifdef hackery
out of a class and creates proper platform-independent typedefs
for the relevant things. This allows these typedefs to be
reused in other places without having to reinvent this preprocessor
logic.
llvm-svn: 334294
O_CLOEXEC is the right default, but occasionally you don't
want this. This is especially true for tools like debuggers
where you might need to spawn the child process with specific
files already open, but it's occasionally useful in other
scenarios as well, like when you want to do some IPC between
parent and child.
llvm-svn: 334293
Simplify combineVectorTruncationWithPACKUS to mask the upper bits followed by calling truncateVectorWithPACK instead of duplicating with similar code.
This results in the codegen using (V)PACKUSDW on SSE41+ targets for vXi64/vXi32 inputs where before it always used PACKUSWB (along with a lot more bitcasting).
I've raised PR37749 as until we avoid unnecessary concats back to 256-bit for bitwise ops, we can't avoid splitting the input value into 128-bit subvectors for masking.
llvm-svn: 334289
Summary: Macros are terribly spammy at the moment and this offers some relief.
Reviewers: ioeric
Subscribers: ilya-biryukov, MaskRay, jkorous, cfe-commits
Differential Revision: https://reviews.llvm.org/D47936
llvm-svn: 334287
Currently the loop branch heuristic is applied before the invoke heuristic which makes us overestimate the probability of the unwind destination of invokes inside loops. This in turn makes us grossly underestimate the frequencies of loops with invokes.
Reviewed By: skatkov, vsk
Differential Revision: https://reviews.llvm.org/D47371
llvm-svn: 334285
This first step separates VPInstruction-based and VPRecipe-based
VPlan creation, which should make it easier to migrate to VPInstruction
based code-gen step by step.
Reviewers: Ayal, rengolin, dcaballe, hsaito, mkuper, mzolotukhin
Reviewed By: dcaballe
Subscribers: bollu, tschuett, rkruppe, llvm-commits
Differential Revision: https://reviews.llvm.org/D47477
llvm-svn: 334284
Summary: Add `StringRef::rsplit(StringRef Separator)` to achieve the function of getting the tail substring according to the separator. A typical usage is to get `data` in `std::basic_string::data`.
Reviewers: mehdi_amini, zturner, beanz, xbolva00, vsk
Reviewed By: zturner, xbolva00, vsk
Subscribers: vsk, xbolva00, llvm-commits, MTC
Differential Revision: https://reviews.llvm.org/D47406
llvm-svn: 334283
Summary:
Default copy/move constructors and assignment operators leave wrong m_sets[i].registers pointers.
Made the class movable and non-copyable (it's difficult to imagine when it needs to be copied).
Reviewers: clayborg
Reviewed By: clayborg
Differential Revision: https://reviews.llvm.org/D47728
llvm-svn: 334282
CGM.GetAddrOfConstantCString() sets the adress of the created GlobalValue
to unnamed. When emitting the object file LLVM will mark the surrounding
section as SHF_MERGE iff the string is nul-terminated and contains no
other nuls (see IsNullTerminatedString). This results in problems when
saving temporaries because LLVM doesn't set an EntrySize, so reading in
the serialized assembly file fails.
This never happened for the GPU binaries because they usually contain
a nul-character somewhere. Instead this only affected the module ID
when compiling relocatable device code.
However, this points to a potentially larger problem: If we put a
constant string into a named section, we really want the data to end
up in that section in the object file. To avoid LLVM merging sections
this patch unmarks the GlobalVariable's address as unnamed which also
fixes the problem of invalid serialized assembly files when saving
temporaries.
Differential Revision: https://reviews.llvm.org/D47902
llvm-svn: 334281
r334215 changed the error message the tool prints for invalid thread
arguments to -exec-next command. This adjust the test to match that.
llvm-svn: 334279
The instruction makes use of a previously ignored field in the fence
instruction. It is introduced in the version 2.3 draft of the RISC-V
specification after much work by the Memory Model Task Group.
As clarified here <https://github.com/riscv/riscv-isa-manual/issues/186>,
the fence.tso assembler mnemonic does not have operands.
llvm-svn: 334278
This also fixes a bug where SymbolFileDWARF was returning the same
function multiple times - this can happen if both mangled and demangled
names match the regex. Other lookup lookup functions had code to handle
this case, but it was forgotten here.
llvm-svn: 334277
Krzysztof Parzyszek