Craig Topper [Fri, 11 Oct 2019 00:38:41 +0000 (00:38 +0000)]
[X86] Update trunc_packus_v32i32_v32i8 test in min-legal-vector-width.ll to use a load for the large type and add the min-legal-vector-width attribute.
The attribute is needed to avoid zmm registers. Using memory
avoids argument splitting for large vectors.
Alina Sbirlea [Thu, 10 Oct 2019 23:27:21 +0000 (23:27 +0000)]
[MemorySSA] Update Phi simplification.
When simplifying a Phi to the unique value found incoming, check that
there wasn't a Phi already created to break a cycle. If so, remove it.
Resolves PR43541.
Craig Topper [Thu, 10 Oct 2019 21:46:52 +0000 (21:46 +0000)]
[X86] Guard against leaving a dangling node in combineTruncateWithSat.
When handling the packus pattern for i32->i8 we do a two step
process using a packss to i16 followed by a packus to i8. If the
final i8 step is a type with less than 64-bits the packus step
will return SDValue(), but the i32->i16 step might have succeeded.
This leaves the nodes from the middle step dangling.
Guard against this by pre-checking that the number of elements is
at least 8 before doing the middle step.
With that check in place this should mean the only other
case the middle step itself can fail is when SSE2 is disabled. So
add an early SSE2 check then just assert that neither the middle
or final step ever fail.
[GISel] Allow getConstantVRegVal() to return G_FCONSTANT values.
In GISel we have both G_CONSTANT and G_FCONSTANT, but because
in GISel we don't really have a concept of Float vs Int value
the only difference between the two is where the data originates
from.
What both G_CONSTANT and G_FCONSTANT return is just a bag of bits
with the constant representation in it.
By making getConstantVRegVal() return G_FCONSTANTs bit representation
as well we allow ConstantFold and other things to operate with
G_FCONSTANT.
Adding tests that show ConstantFolding to work on mixed G_CONSTANT
and G_FCONSTANT sources.
Rong Xu [Thu, 10 Oct 2019 21:30:43 +0000 (21:30 +0000)]
[ValueTracking] Improve pointer offset computation for cases of same base
This patch improves the handling of pointer offset in GEP expressions where
one argument is the base pointer. isPointerOffset() is being used by memcpyopt
where current code synthesizes consecutive 32 bytes stores to one store and
two memset intrinsic calls. With this patch, we convert the stores to one
memset intrinsic.
Alina Sbirlea [Thu, 10 Oct 2019 20:43:06 +0000 (20:43 +0000)]
[MemorySSA] Additional handling of unreachable blocks.
Summary:
Whenever we get the previous definition, the assumption is that the
recursion starts ina reachable block.
If the recursion starts in an unreachable block, we may recurse
indefinitely. Handle this case by returning LoE if the block is
unreachable.
Move the default implementations of cache and prefetch queries to
TargetTransformInfoImplBase and delete them from NoTIIImpl. This brings these
interfaces in line with how other TTI interfaces work.
Zachary Turner [Thu, 10 Oct 2019 20:25:51 +0000 (20:25 +0000)]
[PDB] Fix bug when using multiple PCH header objects with the same name.
A common pattern in Windows is to have all your precompiled headers
use an object named stdafx.obj. If you've got a project with many
different static libs, you might use a separate PCH for each one of
these.
During the final link step, a file from A might reference the PCH
object from A, but it will have the same name (stdafx.obj) as any
other PCH from another project. The only difference will be the
path. For example, A might be A/stdafx.obj while B is B/stdafx.obj.
The existing algorithm checks only the filename that was passed on
the command line (or stored in archive), but this is insufficient in
the case where relative paths are used, because depending on the
command line object file / library order, it might find the wrong
PCH object first resulting in a signature mismatch.
The fix here is to simply check whether the absolute path of the
PCH object (which is stored in the input obj file for the file that
references the PCH) *ends with* the full relative path of whatever
is specified on the command line (or is in the archive).
Jordan Rose [Thu, 10 Oct 2019 20:22:53 +0000 (20:22 +0000)]
ADT: Save a word in every StringSet entry
Add a specialization to StringMap (actually StringMapEntry) for a
value type of NoneType (the type of llvm::None), and use it for
StringSet. This'll save us a word from every entry in a StringSet,
used for alignment with the size_t that stores the string length.
I could have gone all the way to some kind of empty base class
optimization, but that seemed like overkill. Someone can consider
adding that in the future, though.
Julian Lettner [Thu, 10 Oct 2019 19:43:57 +0000 (19:43 +0000)]
[lit] Bring back `--threads` option alias
Bring back `--threads` option which was lost in the move of the
command line argument parsing code to cl_arguments.py. Update docs
since `--workers` is preferred.
Craig Topper [Thu, 10 Oct 2019 19:40:44 +0000 (19:40 +0000)]
[X86] Use packusdw+vpmovuswb to implement v16i32->V16i8 that clamps signed inputs to be between 0 and 255 when zmm registers are disabled on SKX.
If we've disable zmm registers, the v16i32 will need to be split. This split will propagate through min/max the truncate. This creates two sequences that need to be concatenated back to v16i8. We can instead use packusdw to do part of the clamping, truncating, and concatenating all at once. Then we can use a vpmovuswb to finish off the clamp.
Jinsong Ji [Thu, 10 Oct 2019 19:25:30 +0000 (19:25 +0000)]
[PowerPC][docs] Update IBM official docs in Compiler Writers Info page
Summary:
Just realized that most of the links in this page are deprecated.
So update some important reference here:
* adding PowerISA 3.0B/2.7B
* adding P8/P9 User Manual
* ELFv2 ABI and errata
Nico Weber [Thu, 10 Oct 2019 18:57:23 +0000 (18:57 +0000)]
win: Move Parallel.h off concrt to cross-platform code
r179397 added Parallel.h and implemented it terms of concrt in 2013.
In 2015, a cross-platform implementation of the functions has appeared
and is in use everywhere but on Windows (r232419). r246219 hints that
<thread> had issues in MSVC2013, but r296906 suggests they've been fixed
now that we require 2015+.
So remove the concrt code. It's less code, and it sounds like concrt has
conceptual and performance issues, see PR41198.
I built blink_core.dll in a debug component build with full symbols and
in a release component build without any symbols. I couldn't measure a
performance difference for linking blink_core.dll before and after this
patch.
Reid Kleckner [Thu, 10 Oct 2019 18:31:57 +0000 (18:31 +0000)]
Print quoted backslashes in LLVM IR as \\ instead of \5C
This improves readability of Windows path string literals in LLVM IR.
The LLVM assembler has supported \\ in IR strings for a long time, but
the lexer doesn't tolerate escaped quotes, so they have to be printed as
\22 for now.
x86 already tries to fold this pattern, but it isn't done
uniformly, so we still see a diff. AArch64 probably should
enable the TLI hook to benefit too, but that's a follow-on.
Joel E. Denny [Thu, 10 Oct 2019 17:40:12 +0000 (17:40 +0000)]
[lit] Extend internal diff to support -U
When using lit's internal shell, RUN lines like the following
accidentally execute an external `diff` instead of lit's internal
`diff`:
```
# RUN: program | diff -U1 file -
```
Such cases exist now, in `clang/test/Analysis` for example. We are
preparing patches to ensure lit's internal `diff` is called in such
cases, which will then fail because lit's internal `diff` doesn't
recognize `-U` as a command-line option. This patch adds `-U`
support.
Joel E. Denny [Thu, 10 Oct 2019 17:39:57 +0000 (17:39 +0000)]
[lit] Extend internal diff to support `-` argument
When using lit's internal shell, RUN lines like the following
accidentally execute an external `diff` instead of lit's internal
`diff`:
```
# RUN: program | diff file -
```
Such cases exist now, in `clang/test/Analysis` for example. We are
preparing patches to ensure lit's internal `diff` is called in such
cases, which will then fail because lit's internal `diff` doesn't
recognize `-` as a command-line option. This patch adds support for
`-` to mean stdin.
Joel E. Denny [Thu, 10 Oct 2019 17:39:41 +0000 (17:39 +0000)]
[lit] Clean up internal diff's encoding handling
As suggested by rnk at D67643#1673043, instead of reading files
multiple times until an appropriate encoding is found, read them once
as binary, and then try to decode what was read.
For python >= 3.5, don't fail when attempting to decode the
`diff_bytes` output in order to print it.
Joel E. Denny [Thu, 10 Oct 2019 17:39:24 +0000 (17:39 +0000)]
[lit] Make internal diff work in pipelines
When using lit's internal shell, RUN lines like the following
accidentally execute an external `diff` instead of lit's internal
`diff`:
```
# RUN: program | diff file -
# RUN: not diff file1 file2 | FileCheck %s
```
Such cases exist now, in `clang/test/Analysis` for example. We are
preparing patches to ensure lit's internal `diff` is called in such
cases, which will then fail because lit's internal `diff` cannot
currently be used in pipelines and doesn't recognize `-` as a
command-line option.
To enable pipelines, this patch moves lit's `diff` implementation into
an out-of-process script, similar to lit's `cat` implementation. A
follow-up patch will implement `-` to mean stdin.
Greg Clayton [Thu, 10 Oct 2019 17:10:11 +0000 (17:10 +0000)]
Add GsymCreator and GsymReader.
This patch adds the ability to create GSYM files with GsymCreator, and read them with GsymReader. Full testing has been added for both new classes.
This patch differs from the original patch https://reviews.llvm.org/D53379 in that is uses a StringTableBuilder class from llvm instead of a custom version. Support for big and little endian files has been added. If the endianness matches the current host, we use efficient extraction for the header, address table and address info offset tables.
David Green [Thu, 10 Oct 2019 16:04:49 +0000 (16:04 +0000)]
[Codegen] Alter the default promotion for saturating adds and subs
The default promotion for the add_sat/sub_sat nodes currently does:
1. ANY_EXTEND iN to iM
2. SHL by M-N
3. [US][ADD|SUB]SAT
4. L/ASHR by M-N
If the promoted add_sat or sub_sat node is not legal, this can produce code
that effectively does a lot of shifting (and requiring large constants to be
materialised) just to use the overflow flag. It is simpler to just do the
saturation manually, using the higher bitwidth addition and a min/max against
the saturating bounds. That is what this patch attempts to do.
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790
Yonghong Song [Thu, 10 Oct 2019 15:33:09 +0000 (15:33 +0000)]
[BPF] Remove relocation for patchable externs
Previously, patchable extern relocations are introduced to patch
external variables used for multi versioning in
compile once, run everywhere use case. The load instruction
will be converted into a move with an patchable immediate
which can be changed by bpf loader on the host.
The kernel verifier has evolved and is able to load
and propagate constant values, so compiler relocation
becomes unnecessary. This patch removed codes related to this.
Roman Lebedev [Thu, 10 Oct 2019 14:46:21 +0000 (14:46 +0000)]
[MCA] Show aggregate over Average Wait times for the whole snippet (PR43219)
Summary:
As disscused in https://bugs.llvm.org/show_bug.cgi?id=43219,
i believe it may be somewhat useful to show //some// aggregates
over all the sea of statistics provided.
Example:
```
Average Wait times (based on the timeline view):
[0]: Executions
[1]: Average time spent waiting in a scheduler's queue
[2]: Average time spent waiting in a scheduler's queue while ready
[3]: Average time elapsed from WB until retire stage
Kai Nacke [Thu, 10 Oct 2019 13:24:00 +0000 (13:24 +0000)]
[Tests] Output of od can be lower or upper case (llvm-objcopy/yaml2obj).
The command `od -t x` is used to dump data in hex format.
The LIT tests assumes that the hex characters are in lowercase.
However, there are also platforms which use uppercase letter.
To solve this issue the tests are updated to use the new
`--ignore-case` option of FileCheck.
Kai Nacke [Thu, 10 Oct 2019 13:15:41 +0000 (13:15 +0000)]
[FileCheck] Implement --ignore-case option.
The FileCheck utility is enhanced to support a `--ignore-case`
option. This is useful in cases where the output of Unix tools
differs in case (e.g. case not specified by Posix).
Florian Hahn [Thu, 10 Oct 2019 13:07:01 +0000 (13:07 +0000)]
[LV][NFC] Factor out calculation of "best" estimated trip count.
This is just small refactoring to minimize changes in upcoming patch.
In the next path I'm going to introduce changes into heuristic for vectorization of "tiny trip count" loops.
Patch by Evgeniy Brevnov <evgueni.brevnov@gmail.com>
Pavel Labath [Thu, 10 Oct 2019 13:05:46 +0000 (13:05 +0000)]
MinidumpYAML: Add support for the memory info list stream
Summary:
The implementation is fairly straight-forward and uses the same patterns
as the existing streams. The yaml form does not attempt to preserve the
data in the "gaps" that can be created by setting a larger-than-required
header or entry size in the stream header, because the existing consumer
(lldb) does not make use of the information in the gap in any way, and
attempting to preserve that would make the implementation more
complicated.
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790
Roman Lebedev [Thu, 10 Oct 2019 12:22:33 +0000 (12:22 +0000)]
[ADR] ArrayRefTest: disable SizeTSizedOperations test - it's UB.
This test is not defined.
FAIL: LLVM-Unit :: ADT/./ADTTests/ArrayRefTest.SizeTSizedOperations (178 of 33926)
******************** TEST 'LLVM-Unit :: ADT/./ADTTests/ArrayRefTest.SizeTSizedOperations' FAILED ********************
Note: Google Test filter = ArrayRefTest.SizeTSizedOperations
[==========] Running 1 test from 1 test case.
[----------] Global test environment set-up.
[----------] 1 test from ArrayRefTest
[ RUN ] ArrayRefTest.SizeTSizedOperations
/b/sanitizer-x86_64-linux-bootstrap-ubsan/build/llvm-project/llvm/include/llvm/ADT/ArrayRef.h:180:32: runtime error: applying non-zero offset 9223372036854775806 to null pointer
#0 0x5ae8dc in llvm::ArrayRef<char>::slice(unsigned long, unsigned long) const /b/sanitizer-x86_64-linux-bootstrap-ubsan/build/llvm-project/llvm/include/llvm/ADT/ArrayRef.h:180:32
#1 0x5ae44c in (anonymous namespace)::ArrayRefTest_SizeTSizedOperations_Test::TestBody() /b/sanitizer-x86_64-linux-bootstrap-ubsan/build/llvm-project/llvm/unittests/ADT/ArrayRefTest.cpp:85:3
#2 0x928a96 in testing::Test::Run() /b/sanitizer-x86_64-linux-bootstrap-ubsan/build/llvm-project/llvm/utils/unittest/googletest/src/gtest.cc:2474:5
#3 0x929793 in testing::TestInfo::Run() /b/sanitizer-x86_64-linux-bootstrap-ubsan/build/llvm-project/llvm/utils/unittest/googletest/src/gtest.cc:2656:11
#4 0x92a152 in testing::TestCase::Run() /b/sanitizer-x86_64-linux-bootstrap-ubsan/build/llvm-project/llvm/utils/unittest/googletest/src/gtest.cc:2774:28
#5 0x9319d2 in testing::internal::UnitTestImpl::RunAllTests() /b/sanitizer-x86_64-linux-bootstrap-ubsan/build/llvm-project/llvm/utils/unittest/googletest/src/gtest.cc:4649:43
#6 0x931416 in testing::UnitTest::Run() /b/sanitizer-x86_64-linux-bootstrap-ubsan/build/llvm-project/llvm/utils/unittest/googletest/src/gtest.cc:4257:10
#7 0x920ac3 in RUN_ALL_TESTS /b/sanitizer-x86_64-linux-bootstrap-ubsan/build/llvm-project/llvm/utils/unittest/googletest/include/gtest/gtest.h:2233:46
#8 0x920ac3 in main /b/sanitizer-x86_64-linux-bootstrap-ubsan/build/llvm-project/llvm/utils/unittest/UnitTestMain/TestMain.cpp:50:10
#9 0x7f66135b72e0 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x202e0)
#10 0x472c19 in _start (/b/sanitizer-x86_64-linux-bootstrap-ubsan/build/llvm_build_ubsan/unittests/ADT/ADTTests+0x472c19)
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior /b/sanitizer-x86_64-linux-bootstrap-ubsan/build/llvm-project/llvm/include/llvm/ADT/ArrayRef.h:180:32 in
Mirko Brkusanin [Thu, 10 Oct 2019 12:02:14 +0000 (12:02 +0000)]
[Mips] Fix 374055
EXPENSIVE_CHECKS build was failing on new test.
This is fixed by marking $ra register as undef.
Test now has -verify-machineinstrs to check for operand flags.
Summary:
llvm-ar's mri-utf8.test test relies on the en_US.UTF-8 locale to be
installed for its last RUN line to work. If not installed, the unicode
string gets encoded (interpreted) as ascii which fails since the most
significant byte is non zero. This commit changes the test to only rely
on the system being able to encode the pound sign in its default
encoding (e.g. UTF-16 for Microsoft Windows) by always opening the file
via input/output redirection. This avoids forcing a given locale to be
present and supported. A Byte Order Mark is also added to help
recognizing the encoding of the file and its endianness.
Oliver Stannard [Thu, 10 Oct 2019 09:58:28 +0000 (09:58 +0000)]
[IfCvt][ARM] Optimise diamond if-conversion for code size
Currently, the heuristics the if-conversion pass uses for diamond if-conversion
are based on execution time, with no consideration for code size. This adds a
new set of heuristics to be used when optimising for code size.
This is mostly target-independent, because the if-conversion pass can
see the code size of the instructions which it is removing. For thumb,
there are a few passes (insertion of IT instructions, selection of
narrow branches, and selection of CBZ instructions) which are run after
if conversion and affect these heuristics, so I've added target hooks to
better predict the code-size effect of a proposed if-conversion.
Roman Lebedev [Thu, 10 Oct 2019 09:25:02 +0000 (09:25 +0000)]
[UBSan][clang][compiler-rt] Applying non-zero offset to nullptr is undefined behaviour
Summary:
Quote from http://eel.is/c++draft/expr.add#4:
```
4 When an expression J that has integral type is added to or subtracted
from an expression P of pointer type, the result has the type of P.
(4.1) If P evaluates to a null pointer value and J evaluates to 0,
the result is a null pointer value.
(4.2) Otherwise, if P points to an array element i of an array object x with n
elements ([dcl.array]), the expressions P + J and J + P
(where J has the value j) point to the (possibly-hypothetical) array
element i+j of x if 0≤i+j≤n and the expression P - J points to the
(possibly-hypothetical) array element i−j of x if 0≤i−j≤n.
(4.3) Otherwise, the behavior is undefined.
```
Therefore, as per the standard, applying non-zero offset to `nullptr`
(or making non-`nullptr` a `nullptr`, by subtracting pointer's integral value
from the pointer itself) is undefined behavior. (*if* `nullptr` is not defined,
i.e. e.g. `-fno-delete-null-pointer-checks` was *not* specified.)
To make things more fun, in C (6.5.6p8), applying *any* offset to null pointer
is undefined, although Clang front-end pessimizes the code by not lowering
that info, so this UB is "harmless".
Since rL369789 (D66608 `[InstCombine] icmp eq/ne (gep inbounds P, Idx..), null -> icmp eq/ne P, null`)
LLVM middle-end uses those guarantees for transformations.
If the source contains such UB's, said code may now be miscompiled.
Such miscompilations were already observed:
* https://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20190826/687838.html
* https://github.com/google/filament/pull/1566
Surprisingly, UBSan does not catch those issues
... until now. This diff teaches UBSan about these UB's.
`getelementpointer inbounds` is a pretty frequent instruction,
so this does have a measurable impact on performance;
I've addressed most of the obvious missing folds (and thus decreased the performance impact by ~5%),
and then re-performed some performance measurements using my [[ https://github.com/darktable-org/rawspeed | RawSpeed ]] benchmark:
(all measurements done with LLVM ToT, the sanitizer never fired.)
* no sanitization vs. existing check: average `+21.62%` slowdown
* existing check vs. check after this patch: average `22.04%` slowdown
* no sanitization vs. this patch: average `48.42%` slowdown
to make the expected test output depend on as few optimization phases
as possible, for stability. But when you write a RUN line of this
form, you lose the ability to use update_cc_test_checks.py to
automatically generate the expected output, because it only supports
two-stage pipelines consisting of '%clang | FileCheck' (or %clang_cc1).
This change extends the set of supported RUN lines so that pipelines
with an invocation of `opt` in the middle can still be automatically
handled.
To implement it, I've adjusted `get_function_body()` so that it can
cope with an arbitrary sequence of intermediate pipeline commands. But
the code that decides which RUN lines to consider is more
conservative: it only adds clang | opt | FileCheck to the set of
supported lines, because I didn't want to accidentally include some
other kind of line that doesn't output IR at all.
(Also in this commit is the minimal change to make this script work at
all, after r373912 added an extra parameter to `add_ir_checks`.)
Matt Arsenault [Thu, 10 Oct 2019 07:11:33 +0000 (07:11 +0000)]
AMDGPU: Use SGPR_128 instead of SReg_128 for vregs
SGPR_128 only includes the real allocatable SGPRs, and SReg_128 adds
the additional non-allocatable TTMP registers. There's no point in
allocating SReg_128 vregs. This shrinks the size of the classes
regalloc needs to consider, which is usually good.
[Attributor] Handle `null` differently in capture and alias logic
Summary:
`null` in the default address space (=AS 0) cannot be captured nor can
it alias anything. We make this clear now as it can be important for
callbacks and other cases later on. In addition, this patch improves the
debug output for noalias deduction.
Reid Kleckner [Thu, 10 Oct 2019 01:06:01 +0000 (01:06 +0000)]
[codeview] Try to avoid emitting .cv_loc with line zero
Summary:
Visual Studio doesn't like it while stepping. It kicks you out of the
source view of the file being stepped through and tries to fall back to
the disassembly view.
Fixes PR43530
The fix is incomplete, because it's possible to have a basic block with
no source locations at all. In this case, we don't emit a .cv_loc, but
that will result in wrong stepping behavior in the debugger if the
layout predecessor of the location-less BB has an unrelated source
location. We could try harder to find a valid location that dominates or
post-dominates the current BB, but in general it's a dataflow problem,
and one still might not exist. I left a FIXME about this.
As an alternative, we might want to consider having the middle-end check
if its emitting codeview and get it to stop using line zero.
Philip Reames [Wed, 9 Oct 2019 23:43:33 +0000 (23:43 +0000)]
Conservatively add volatility and atomic checks in a few places
As background, starting in D66309, I'm working on support unordered atomics analogous to volatile flags on normal LoadSDNode/StoreSDNodes for X86.
As part of that, I spent some time going through usages of LoadSDNode and StoreSDNode looking for cases where we might have missed a volatility check or need an atomic check. I couldn't find any cases that clearly miscompile - i.e. no test cases - but a couple of pieces in code loop suspicious though I can't figure out how to exercise them.
This patch adds defensive checks and asserts in the places my manual audit found. If anyone has any ideas on how to either a) disprove any of the checks, or b) hit the bug they might be fixing, I welcome suggestions.