If we do not initialize Prefix here, Prefix.data() returns a nullptr.
Later, it is passed to memcpy. memcpy's behavior is undefined if src (or
dst) is a nullptr even if a given size is 0. That's why this code
triggered UBsan.
This patch produces a crash and hexagon_vector_loop_carried_reuse_constant.ll test fails on Windows (llvm-clang-x86_64-expensive-checks-win build bot).
Revert r314017 '[InstCombine] Simplify check for RHS being a splat constant in foldICmpUsingKnownBits by just checking Op1Min==Op1Max rather than going through m_APInt.'
This reverts r314017 and similar code added in later commits. It seems to not work for pointer compares and is causing a bot failure for the last several days.
The tar format originally supported up to 99 byte filename. The two
extensions are proposed later: Ustar or PAX.
In the UStar extension, a pathanme is split at a '/' and its "prefix"
and "suffix" are stored in different locations in the tar header. Since
"prefix" can be up to 155 byte, it can represent up to 254 byte
filename (but exact limit depends on the location of '/' character in
a pathname.)
Our TarWriter first attempt to use UStar extension and then fallback to
PAX extension.
But there's a bug in UStar header creation. "Suffix" part must be a NUL-
terminated string, but we didn't handle it correctly. As a result, if
your filename just 100 characters long, the last character was droppped.
Brian Gesiak [Wed, 27 Sep 2017 21:37:33 +0000 (21:37 +0000)]
[CMake] Fix typo: "in-tree" -> "in-source" (NFC)
Summary:
*In-source builds* of LLVM, in which a user invokes `cmake` from within the
LLVM source directory, or invokes `cmake -B/path/to/source/dir/of/llvm`,
are explicitly checked for and disallowed by LLVM's `CMakeLists.txt`.
*In-tree builds*, on the other hand, refer to when the source directories
of projects such as Clang are nested within the `llvm/tools` source
directory. These are not disallowed, and are in fact a common way of
building LLVM and Clang.
Revise the comment to match the logic underneath it: it checks for an
"in-source build", not an "in-tree build".
Do not remove a target file in FileOutputBuffer::create().
FileOutputBuffer::create() attempts to remove a target file if the file
is a regular one, which results in an unexpected result in a failure
scenario.
If something goes wrong and the user of FileOutputBuffer decides to not
call commit(), it leaves nothing. An existing file is removed, and no
new file is created.
What we should do is to atomically replace an existing file with a new
file using rename(), so that it wouldn't remove an existing file without
creating a new one.
[MachineOutliner] AArch64: Avoid saving + restoring LR if possible
This commit allows the outliner to avoid saving and restoring the link register
on AArch64 when it is dead within an entire class of candidates.
This introduces changes to the way the outliner interfaces with the target.
For example, the target now interfaces with the outliner using a
MachineOutlinerInfo struct rather than by using getOutliningCallOverhead and
getOutliningFrameOverhead.
This also improves several comments on the outliner's cost model.
Than McIntosh [Wed, 27 Sep 2017 19:34:00 +0000 (19:34 +0000)]
[CodeGen] Emit necessary .note sections for -fsplit-stack
Summary:
According to https://gcc.gnu.org/wiki/SplitStacks, the linker expects a zero-sized .note.GNU-split-stack section if split-stack is used (and also .note.GNU-no-split-stack section if it also contains non-split-stack functions), so it can handle the cases where a split-stack function calls non-split-stack function.
[X86] In combineLoopSADPattern, pad result with zeros and use full size add instead of using a smaller add and inserting.
In some cases the result psadbw is smaller than the type of the add that started the match. Currently in these cases we are using a smaller add and inserting the result.
If we instead combine the psadbw with zeros and use the full size add we can take advantage of implicit zeroing we get if we emit a narrower move before the add.
In a future patch, I want to make isel aware that the psadbw itself already zeroed the upper bits and remove the move entirely.
[SLP] Fix crash on propagate IR flags for undef operands of min/max
reductions.
If both operands of the newly created SelectInst are Undefs the
resulting operation is also Undef, not SelectInst. It may cause crashes
when trying to propagate IR flags because function expects exactly
SelectInst instruction, nothing else.
These changes faciliate positive behavior for arithmetic based select
expressions that match its translation criteria, keeping code size gated to
neutral or improved scenarios.
Roman Lebedev [Wed, 27 Sep 2017 15:59:16 +0000 (15:59 +0000)]
[Support] mapped_file_region: store size as size_t
Summary:
Found when testing stage-2 build with D38101.
```
In file included from /build/llvm/lib/Support/Path.cpp:1045:
/build/llvm/lib/Support/Unix/Path.inc:648:14: error: comparison 'uint64_t' (aka 'unsigned long') > 18446744073709551615 is always false [-Werror,-Wtautological-constant-compare]
if (length > std::numeric_limits<size_t>::max()) {
~~~~~~ ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
```
`size_t` is `uint64_t` here, apparently, thus any `uint64_t` value
always fits into `size_t`.
Initial patch was to use some preprocessor logic to
not check if the size is known to fit at compile time.
But Zachary Turner suggested using this approach.
Sean Eveson [Wed, 27 Sep 2017 15:37:40 +0000 (15:37 +0000)]
[llvm-cov] Create directory structure when filtering using -name*= options
Before this change using any of the -name*= command line options with an output
directory would result in a single file (functions.txt/functions.html)
containing the coverage for those specific functions. Now you get the same
directory structure as when not using any -name*= options.
[SimplifyCFG] add a struct to house optional folds (PR34603)
This was intended to be no-functional-change, but it's not - there's a test diff.
So I thought I should stop here and post it as-is to see if this looks like what was expected
based on the discussion in PR34603:
https://bugs.llvm.org/show_bug.cgi?id=34603
Notes:
1. The test improvement occurs because the existing 'LateSimplifyCFG' marker is not carried
through the recursive calls to 'SimplifyCFG()->SimplifyCFGOpt().run()->SimplifyCFG()'.
The parameter isn't passed down, so we pick up the default value from the function signature
after the first level. I assumed that was a bug, so I've passed 'Options' down in all of the
'SimplifyCFG' calls.
2. I split 'LateSimplifyCFG' into 2 bits: ConvertSwitchToLookupTable and KeepCanonicalLoops.
This would theoretically allow us to differentiate the transforms controlled by those params
independently.
3. We could stash the optional AssumptionCache pointer and 'LoopHeaders' pointer in the struct too.
I just stopped here to minimize the diffs.
4. Similarly, I stopped short of messing with the pass manager layer. I have another question that
could wait for the follow-up: why is the new pass manager creating the pass with LateSimplifyCFG
set to true no matter where in the pipeline it's creating SimplifyCFG passes?
// Create an early function pass manager to cleanup the output of the
// frontend.
EarlyFPM.addPass(SimplifyCFGPass());
-->
/// \brief Construct a pass with the default thresholds
/// and switch optimizations.
SimplifyCFGPass::SimplifyCFGPass()
: BonusInstThreshold(UserBonusInstThreshold),
LateSimplifyCFG(true) {} <-- switches get converted to lookup tables and loops may not be in canonical form
If this is unintended, then it's possible that the current behavior of dropping the 'LateSimplifyCFG'
setting via recursion was masking this bug.
InlineCost can understand Select IR now. This patch finds free Select IRs and
continue the propagation of SimplifiedValues, ConstantOffsetPtrs, and
SROAArgValues.
Gadi Haber [Wed, 27 Sep 2017 14:44:15 +0000 (14:44 +0000)]
[X86][SKX][KNL] Updated regression tests to use -mattr instead of -mcpu flag.NFC.
NFC.
Updated 8 regression tests to use -mattr instead of -mcpu flag as follows:
-mcpu=knl --> -mattr=+avx512f
-mcpu=skx --> -mattr=+avx512f,+avx512bw,+avx512vl,+avx512dq
The updates are as part of the preparation of a large commit to add all instruction scheduling for the SKX target.
[PowerPC] eliminate unconditional branch to the next instruction
This patch makes analyzeBranch eliminate unconditional branch to the next instruction.
After basic blocks are re-organized by optimizers, such as machine block placement, a BB may end with an unconditional branch to the next (fallthrough) BB. This patch removes such redundant branch instruction.
Sam Parker [Wed, 27 Sep 2017 08:30:45 +0000 (08:30 +0000)]
[ARM] isTruncateFree fix
I implemented isTruncateFree in rL313533, this patch fixes the logic
to match my comment, as the previous logic was too general. Now the
only truncates that are free are i64 -> i32.
Martin Storsjo [Wed, 27 Sep 2017 06:08:16 +0000 (06:08 +0000)]
[X86] Remove erroneous callsite offsetting in SJLJ landing pads
The callsite value is already stored indexed from 0 in
the _Unwind_Context struct. When accessed via the functions
_Unwind_GetIP and _Unwind_SetIP, the value is indexed from 1,
but those functions handle the offseting. When reading directly
from the struct here, we shouldn't subtract 1.
This matches the code generated by the ARM target, where SJLJ
exception handling is used by default on iOS.
This makes clang-built object files for 32 bit x86 mingw work when
linked with libgcc/libstdc++.
Martin Pelikan [Wed, 27 Sep 2017 04:48:03 +0000 (04:48 +0000)]
[XRay] convert FDR arg1 log entries
Summary:
A new FDR metadata record will support logging a function call argument;
appending multiple metadata records will represent a sequence of arguments
meaning that "holes" are not representable by the buffer format. Each
call argument is currently a 64-bit value (useful for "this" pointers and
synchronization objects).
If present, we put this argument to the function call "entry" record it
belongs to, and alter its type to notify the user of its presence.
Sanjoy Das [Tue, 26 Sep 2017 21:54:27 +0000 (21:54 +0000)]
[BypassSlowDivision] Improve our handling of divisions by constants
Summary:
Don't bail out on constant divisors for divisions that can be narrowed without
introducing control flow . This gives us a 32 bit multiply instead of an
emulated 64 bit multiply in the generated PTX assembly.
[AArch64][Falkor] Fix bug in falkor prefetcher fix pass.
Summary:
In rare cases, loads that don't get prefetched that were marked as
strided loads could cause a crash if they occurred in a loop with other
colliding loads.
[AArch64][Falkor] Fix correctness bug in falkor prefetcher fix pass and correct some opcode tag computations.
Summary:
This addresses a correctness bug for LD[1234]*_POST opcodes that have
the prefetcher fix applied to them: the base register was not being
written back from the temp after being incremented, so it would appear
to never be incremented.
Also, fix some opcode tag computations based on some updated HW details
to get better tag avoidance and thus better prefetcher performance.
[X86] Don't emit X86::MOV8rr_NOREX from X86InstrInfo::copyPhysReg.
This hook is called after register allocation with two physical registers. We don't need a separate instruction at that time to force register class constraints. I left in the assert though. We also have a fatal error in X86MCCodeEmitter if we ever encode an H-reg and a REX prefix.
Sam Clegg [Tue, 26 Sep 2017 21:10:09 +0000 (21:10 +0000)]
[WebAssembly] Model weakly defined symbols as wasm exports
Previously these were being included as both imports and
exports, with the import being satisfied by the export
(or some strong symbol) at runtime. However proved
unnecessary and actually complicated linking as it meant
there was not a 1-to-1 mapping between a wasm function
/global index and a linker symbol.
[PowerPC] Reverting sequence of patches for elimination of comparison instructions
In the past while, I've committed a number of patches in the PowerPC back end
aimed at eliminating comparison instructions. However, this causes some failures
in proprietary source and these issues are not observed in SPEC or any open
source packages I've been able to run.
As a result, I'm pulling the entire series and will refactor it to:
- Have a single entry point for easy control
- Have fine-grained control over which patterns we transform
A side-effect of this is that test cases for these patches (and modified by
them) are XFAIL-ed. This is a temporary measure as it is counter-productive
to remove/modify these test cases and then have to modify them again when
the refactored patch is recommitted.
The failure will be investigated in parallel to the refactoring effort and
the recommit will either have a fix for it or will leave this transformation
off by default until the problem is resolved.
[X86][LLVM]Expanding Supports lowerInterleavedStore() in X86InterleavedAccess (VF{8|16|32} stride 3)
This patch expands the support of lowerInterleavedStore to {8|16|32}x8i stride 3.
LLVM creates suboptimal shuffle code-gen for AVX2. In overall, this patch is a specific fix for the pattern (Strid=3 VF={8|16|32}) .
This patch is part two of two patches and it covers the store (interlevaed) side.
The patch goal is to optimize the following sequence:
a0 a1 a2 a3 a4 a5 a6 a7
b0 b1 b2 b3 b4 b5 b6 b7
c0 c1 c2 c3 c4 c5 c6 c7
[InstCombine] Remove one use restriction on the shift for calls to foldICmpAndShift.
If this transformation succeeds, we're going to remove our dependency on the shift by rewriting the and. So it doesn't matter how many uses the shift has.
This distributes the one use check to other transforms in foldICmpAndConstConst that do need it.
Sam Clegg [Tue, 26 Sep 2017 18:21:12 +0000 (18:21 +0000)]
[WebAssembly] Use function/global index space in WasmSymbol
It is useful for the symbol to contain the index of the
function of global it represents in the function/global
index space.
For imports we also store the import index so that the
linker can find, for example, the signature of the
corresponding function, which is defined by the import
In the long run we need to decide whether this API
surface should be closer to binary (where imported
functions are seperate) or the wasm spec (where the
function index space is unified).
When dsymutil generates the companion file, its strips all unnecessary
sections by omitting their body and setting the offset in their
corresponding load command to zero.
One such section is the .eh_frame section, as it contains runtime
information rather than debug information and is part of the __TEXT
segment. When reading this section, we would just read the number of
bytes specified in the load command, starting from offset 0 (i.e. the
beginning of the file).
Rather than trying to parse this obviously invalid section, dwarfdump
now skips this.
Simon Pilgrim [Tue, 26 Sep 2017 14:12:50 +0000 (14:12 +0000)]
[X86][XOP] Merge rotation opcodes with AVX512 equivalents. NFCI.
The XOP rotations act as ROTL with +ve values and ROTR with -ve values, which means that we can treat them all as ROTL with unsigned modulo. We already check that we're only trying to lower as ROTL for XOP rotations.
[DSE] Merge stores when the later store only writes to memory locations the early store also wrote to (2nd try)
This is a 2nd attempt at:
https://reviews.llvm.org/rL310055
...which was reverted at rL310123 because of PR34074:
https://bugs.llvm.org/show_bug.cgi?id=34074
In this version, we break out of the inner loop after we successfully merge and kill a pair of stores. In the
earlier rev, we were continuing instead, which meant we could process the invalid info from a now dead store.
Original commit message (authored by Filipe Cabecinhas):
This fixes PR31777.
If both stores' values are ConstantInt, we merge the two stores
(shifting the smaller store appropriately) and replace the earlier (and
larger) store with an updated constant.
In the future we should also support vectors of integers. And maybe
float/double if we can.
This patch adds logic to follow a symbol's aliases when the symbol name
cannot be found in the current object file. It checks the main binary
for the symbol's address and queries the current object for its aliases
(symbols with the same address) before printing out a warning.
[X86] Finishing broadcastf32x2 and broadcasti32x2 intrinsics lowering to IR. llvm side.
Removing X86 broadcast(f/i)32x2 intrinsics from llvm.
Adding autoUpgrade support.
Moving matching tests from avx512dq-intrinsics.ll to avx512dq-intrinsics-upgrade.ll and from avx512dqvl-intrinsics.ll to avx512dqvl-intrinsics-upgrade.ll.
Usually the frontend communicates the size of wchar_t via metadata and
we can optimize wcslen (and possibly other calls in the future). In
cases without the wchar_size metadata we would previously try to guess
the correct size based on the target triple; however this is fragile to
keep up to date and may miss users manually changing the size via flags.
Better be safe and stop guessing and optimizing if the frontend didn't
communicate the size.
[llvm-cov] Warn if -show-functions is used without query files
llvm-cov's report mode does not print any output when -show-functions is
specified and no source files are specified. This can be surprising, so
the tool should at least print out an error message when this happens.