Commit Graph

308125 Commits

Author SHA1 Message Date
Alexey Bataev 897129dc3f [DEBUGINFO, NVPTX] Enable support for the debug info on NVPTX target.
Enable full support for the debug info.

Differential revision: https://reviews.llvm.org/D46189

llvm-svn: 351974
2019-01-23 18:59:54 +00:00
Alexey Bataev 25624e2e5b Revert "[DEBUGINFO, NVPTX] Enable support for the debug info on NVPTX target."
This reverts commit r351972. Some pieces of the patch was not applied
correctly.

llvm-svn: 351973
2019-01-23 18:48:36 +00:00
Alexey Bataev fe0b356063 [DEBUGINFO, NVPTX] Enable support for the debug info on NVPTX target.
Enable full support for the debug info. Recommit to fix the emission of
the not required closing brace.

Differential revision: https://reviews.llvm.org/D46189

llvm-svn: 351972
2019-01-23 18:28:59 +00:00
Marshall Clow 8681a3bc85 Commit D11348: 'Win32 support: wcsnrtombs and mbsnrtowcs don't handle null output buffers correctly' which has been hanging around for a long time
llvm-svn: 351971
2019-01-23 18:27:22 +00:00
Craig Topper aa0e74c1fc [X86] Autogenerate complete checks. NFC
llvm-svn: 351970
2019-01-23 18:25:49 +00:00
Aaron Ballman b0d74bfe81 Merge similar target diagnostics for interrupt attribute into one; NFC
Patch by Kristina Bessonova!

llvm-svn: 351969
2019-01-23 18:02:17 +00:00
James Henderson 25ce596cd1 [llvm-symbolizer] Improve compatibility of --functions with GNU addr2line
This fixes https://bugs.llvm.org/show_bug.cgi?id=40072.

GNU addr2line's --functions switch is off by default, has a short alias
of -f, and does not take an argument. This patch changes llvm-symbolizer
to allow the second and third point (changing the default behaviour may
have negative impacts on users). If the option is missing a value, it
now treats it as "linkage".

This change does cause one previously valid command-line to behave
differently. Before --functions <value> was accepted, but now only
--functions=<value> is allowed (as well as --functions). The old
behaviour will result in the value being treated as a positional
argument.

The previous testing for --functions=short has been pulled out into a
new test that also tests the other accepted values and option formats.

Reviewed by: ruiu

Differential Revision: https://reviews.llvm.org/D57049

llvm-svn: 351968
2019-01-23 17:27:48 +00:00
Haojian Wu 15a77418a9 Revert "[DEBUGINFO, NVPTX] Enable support for the debug info on NVPTX target."
This reverts commit r351846.

This patch may generate illegal assembly code, see

```
$ ./bin/clang -cc1 -triple nvptx64-nvidia-cuda -aux-triple x86_64-grtev4-linux-gnu -S -disable-free -disable-llvm-verifier -discard-value-names -main-file-name new.cc -mrelocation-model pic -pic-level 2 -mthread-model posix -fmerge-all-constants -mdisable-fp-elim -relaxed-aliasing -no-integrated-as -mpie-copy-relocations -munwind-tables -fcuda-is-device -target-feature +ptx60 -target-cpu sm_35 -dwarf-column-info -debug-info-kind=line-directives-only -dwarf-version=2 -debugger-tuning=gdb -o empty.s -x cuda empty.cc
$  cat empty.s
//
// Generated by LLVM NVPTX Back-End
//

.version 6.0
.target sm_35
.address_size 64

	}
```

llvm-svn: 351966
2019-01-23 16:39:57 +00:00
Andrea Di Biagio d768d35515 [MC][X86] Correctly model additional operand latency caused by transfer delays from the integer to the floating point unit.
This patch adds a new ReadAdvance definition named ReadInt2Fpu.
ReadInt2Fpu allows x86 scheduling models to accurately describe delays caused by
data transfers from the integer unit to the floating point unit.
ReadInt2Fpu currently defaults to a delay of zero cycles (i.e. no delay) for all
x86 models excluding BtVer2. That means, this patch is only a functional change
for the Jaguar cpu model only.

Tablegen definitions for instructions (V)PINSR* have been updated to account for
the new ReadInt2Fpu. That read is mapped to the the GPR input operand.
On Jaguar, int-to-fpu transfers are modeled as a +6cy delay. Before this patch,
that extra delay was added to the opcode latency. In practice, the insert opcode
only executes for 1cy. Most of the actual latency is actually contributed by the
so-called operand-latency. According to the AMD SOG for family 16h, (V)PINSR*
latency is defined by expression f+1, where f is defined as a forwarding delay
from the integer unit to the fpu.

When printing instruction latency from MCA (see InstructionInfoView.cpp) and LLC
(only when flag -print-schedule is speified), we now need to account for any
extra forwarding delays. We do this by checking if scheduling classes declare
any negative ReadAdvance entries. Quoting a code comment in TargetSchedule.td:
"A negative advance effectively increases latency, which may be used for
cross-domain stalls". When computing the instruction latency for the purpose of
our scheduling tests, we now add any extra delay to the formula. This avoids
regressing existing codegen and mca schedule tests. It comes with the cost of an
extra (but very simple) hook in MCSchedModel.

Differential Revision: https://reviews.llvm.org/D57056

llvm-svn: 351965
2019-01-23 16:35:07 +00:00
James Henderson 21ed868390 [llvm-readelf] Don't suppress static symbol table with --dyn-symbols + --symbols
In r287786, a bug was introduced into llvm-readelf where it didn't print
the static symbol table if both --symbols and --dyn-symbols were
specified, even if there was no dynamic symbol table. This is obviously
incorrect.

This patch fixes this issue, by delegating the decision of which symbol
tables should be printed to the final dumper, rather than trying to
decide in the command-line option handling layer. The decision was made
to follow the approach taken in this patch because the LLVM style dumper
uses a different order to the original GNU style behaviour (and GNU
readelf) for ELF output. Other approaches resulted in behaviour changes
for other dumpers which felt wrong. In particular, I wanted to avoid
changing the order of the output for --symbols --dyn-symbols for LLVM
style, keep what is emitted by --symbols unchanged for all dumpers, and
avoid having different orders of .dynsym and .symtab dumping for GNU
"--symbols" and "--symbols --dyn-symbols".

Reviewed by: grimar, rupprecht

Differential Revision: https://reviews.llvm.org/D57016

llvm-svn: 351960
2019-01-23 16:15:39 +00:00
Simon Pilgrim ac5b775522 Fix indentation. NFCI.
llvm-svn: 351958
2019-01-23 16:01:19 +00:00
Simon Pilgrim f87226eb70 [IR] Match intrinsic parameter by scalar/vectorwidth
This patch replaces the existing LLVMVectorSameWidth matcher with LLVMScalarOrSameVectorWidth.

The matching args must be either scalars or vectors with the same number of elements, but in either case the scalar/element type can differ, specified by LLVMScalarOrSameVectorWidth.

I've updated the _overflow intrinsics to demonstrate this - allowing it to return a i1 or <N x i1> overflow result, matching the scalar/vectorwidth of the other (add/sub/mul) result type.

The masked load/store/gather/scatter intrinsics have also been updated to use this, although as we specify the reference type to be llvm_anyvector_ty we guarantee the mask will be <N x i1> so no change in behaviour

Differential Revision: https://reviews.llvm.org/D57090

llvm-svn: 351957
2019-01-23 16:00:22 +00:00
Krzysztof Parzyszek 036715408a [Hexagon] Remove incorrect bit negation
llvm-svn: 351956
2019-01-23 15:36:33 +00:00
Benjamin Kramer 4ebed81fc4 [AArch64] Fix out of bounds strlen
CFIInst is not zero-terminated. This is one of more annoying functional
differences between StringRef and ArrayRef.

Found by asan.

llvm-svn: 351955
2019-01-23 14:51:21 +00:00
Clement Courbet c7956346da Re-land rL322538 "Add a value_type to ArrayRef."
llvm-svn: 351954
2019-01-23 14:20:59 +00:00
Simon Pilgrim 0e08b6f017 Move saturated arithmetic intrinsics to other integer intrinsics. NFCI.
They were in the floating point group.

llvm-svn: 351953
2019-01-23 13:49:10 +00:00
Nico Weber 8874aef822 Disable test better.
llvm-svn: 351952
2019-01-23 13:43:42 +00:00
George Rimar 617adef933 [llvm-objdump] - Move common code to a new printRelocation() helper. NFC.
This extracts the common code for printing relocations into a new helper function.

llvm-svn: 351951
2019-01-23 13:39:12 +00:00
Tim Renouf f64f8efe13 [AMDGPU] With XNACK, cannot clause a load with result coalesced with operand
Summary:
With XNACK, an smem load whose result is coalesced with an operand (thus
it overwrites its own operand) cannot appear in a clause, because some
other instruction might XNACK and restart the whole clause.

The clause breaker already realized that an smem that overwrites an
operand cannot appear in a clause, and broke the clause. The problem
that this commit fixes is that the SIFormMemoryClauses optimization
formed a bundle with early clobber, which caused the earlier code that
set up the coalesced operand to be removed as dead.

Differential Revision: https://reviews.llvm.org/D57008

Change-Id: I703c4d5b0bf7d6060222bec491f45c18bb3c0016
llvm-svn: 351950
2019-01-23 13:38:06 +00:00
Nico Weber 53c3c2c61c Disable test added in r351916.
It doesn't pass on Windows:
http://lab.llvm.org:8011/builders/clang-x64-windows-msvc/builds/3627

FAIL: lld :: ELF/stdout.s (1521 of 1966)
******************** TEST 'lld :: ELF/stdout.s' FAILED ********************
Script:
--
: 'RUN: at line 3';   C:\b\slave\clang-x64-windows-msvc\build\build\stage1\bin\llvm-mc.EXE -filetype=obj -triple=x86_64-unknown-linux C:\b\slave\clang-x64-windows-msvc\build\llvm.src\tools\lld\test\ELF\stdout.s -o C:\b\slave\clang-x64-windows-msvc\build\build\stage1\tools\lld\test\ELF\Output\stdout.s.tmp.o
: 'RUN: at line 4';   c:\b\slave\clang-x64-windows-msvc\build\build\stage1\bin\ld.lld.EXE C:\b\slave\clang-x64-windows-msvc\build\build\stage1\tools\lld\test\ELF\Output\stdout.s.tmp.o -o - > C:\b\slave\clang-x64-windows-msvc\build\build\stage1\tools\lld\test\ELF\Output\stdout.s.tmp1
: 'RUN: at line 5';   C:\b\slave\clang-x64-windows-msvc\build\build\stage1\bin\llvm-objdump.EXE -d C:\b\slave\clang-x64-windows-msvc\build\build\stage1\tools\lld\test\ELF\Output\stdout.s.tmp1 | C:\b\slave\clang-x64-windows-msvc\build\build\stage1\bin\FileCheck.EXE C:\b\slave\clang-x64-windows-msvc\build\llvm.src\tools\lld\test\ELF\stdout.s
: 'RUN: at line 10';   c:\b\slave\clang-x64-windows-msvc\build\build\stage1\bin\ld.lld.EXE C:\b\slave\clang-x64-windows-msvc\build\build\stage1\tools\lld\test\ELF\Output\stdout.s.tmp.o -o C:\b\slave\clang-x64-windows-msvc\build\build\stage1\tools\lld\test\ELF\Output\stdout.s.tmp2
: 'RUN: at line 11';   diff C:\b\slave\clang-x64-windows-msvc\build\build\stage1\tools\lld\test\ELF\Output\stdout.s.tmp1 C:\b\slave\clang-x64-windows-msvc\build\build\stage1\tools\lld\test\ELF\Output\stdout.s.tmp2
--
Exit Code: 1

Command Output (stdout):
--
$ ":" "RUN: at line 3"
$ "C:\b\slave\clang-x64-windows-msvc\build\build\stage1\bin\llvm-mc.EXE" "-filetype=obj" "-triple=x86_64-unknown-linux" "C:\b\slave\clang-x64-windows-msvc\build\llvm.src\tools\lld\test\ELF\stdout.s" "-o" "C:\b\slave\clang-x64-windows-msvc\build\build\stage1\tools\lld\test\ELF\Output\stdout.s.tmp.o"
$ ":" "RUN: at line 4"
$ "c:\b\slave\clang-x64-windows-msvc\build\build\stage1\bin\ld.lld.EXE" "C:\b\slave\clang-x64-windows-msvc\build\build\stage1\tools\lld\test\ELF\Output\stdout.s.tmp.o" "-o" "-"
$ ":" "RUN: at line 5"
$ "C:\b\slave\clang-x64-windows-msvc\build\build\stage1\bin\llvm-objdump.EXE" "-d" "C:\b\slave\clang-x64-windows-msvc\build\build\stage1\tools\lld\test\ELF\Output\stdout.s.tmp1"
$ "C:\b\slave\clang-x64-windows-msvc\build\build\stage1\bin\FileCheck.EXE" "C:\b\slave\clang-x64-windows-msvc\build\llvm.src\tools\lld\test\ELF\stdout.s"
$ ":" "RUN: at line 10"
$ "c:\b\slave\clang-x64-windows-msvc\build\build\stage1\bin\ld.lld.EXE" "C:\b\slave\clang-x64-windows-msvc\build\build\stage1\tools\lld\test\ELF\Output\stdout.s.tmp.o" "-o" "C:\b\slave\clang-x64-windows-msvc\build\build\stage1\tools\lld\test\ELF\Output\stdout.s.tmp2"
$ ":" "RUN: at line 11"
$ "diff" "C:\b\slave\clang-x64-windows-msvc\build\build\stage1\tools\lld\test\ELF\Output\stdout.s.tmp1" "C:\b\slave\clang-x64-windows-msvc\build\build\stage1\tools\lld\test\ELF\Output\stdout.s.tmp2"
# command output:
*** C:\b\slave\clang-x64-windows-msvc\build\build\stage1\tools\lld\test\ELF\Output\stdout.s.tmp1
--- C:\b\slave\clang-x64-windows-msvc\build\build\stage1\tools\lld\test\ELF\Output\stdout.s.tmp2
***************
*** 1 ****

llvm-svn: 351949
2019-01-23 12:35:08 +00:00
Martin Storsjo 0d19a399a3 [llvm-objcopy] [COFF] Error out on use of unhandled options
Prefer erroring out than silently not doing what was requested.

Differential Revision: https://reviews.llvm.org/D57045

llvm-svn: 351948
2019-01-23 11:54:55 +00:00
Martin Storsjo 1be91958b3 [llvm-objcopy] [COFF] Fix handling of aux symbols for big objects
The aux symbols were stored in an opaque std::vector<uint8_t>,
with contents interpreted according to the rest of the symbol.

All aux symbol types but one fit in 18 bytes (sizeof(coff_symbol16)),
and if written to a bigobj, two extra padding bytes are written (as
sizeof(coff_symbol32) is 20). In the storage agnostic intermediate
representation, store the aux symbols as a series of coff_symbol16
sized opaque blobs. (In practice, all such aux symbols only consist
of one aux symbol, so this is more flexible than what reality needs.)

The special case is the file aux symbols, which are written in
potentially more than one aux symbol slot, without any padding,
as one single long string. This can't be stored in the same opaque
vector of fixed sized aux symbol entries. The file aux symbols will
occupy a different number of aux symbol slots depending on the type
of output object file. As nothing in the intermediate process needs
to have accurate raw symbol indices, updating that is moved into the
writer class.

Differential Revision: https://reviews.llvm.org/D57009

llvm-svn: 351947
2019-01-23 11:54:51 +00:00
Martin Storsjo 481334056f [llvm-objcopy] [COFF] Remove testcase debugging lines. NFC.
These are no longer necessary as the testcase now seems to run fine
on the buildbots that previously failed on this case, after SVN r351934.

llvm-svn: 351946
2019-01-23 11:54:36 +00:00
Florian Hahn 68cea130df [HotColdSplitting] Remove unused SSAUpdater.h include (NFC).
llvm-svn: 351945
2019-01-23 11:51:38 +00:00
Kamil Rytarowski 776cf71d4f Mark more tests flaky
Reported on the NetBSD 8 buildbot

llvm-svn: 351944
2019-01-23 11:36:19 +00:00
Ilya Biryukov 88d7d296f4 [clangd] Workaround a test failure after r351941
This should fix failing buildbots.

llvm-svn: 351943
2019-01-23 11:32:07 +00:00
George Rimar fd383e7e22 [llvm-objdump] - Move variable. NFC.
It was too far from the place where it is used.

llvm-svn: 351942
2019-01-23 10:52:38 +00:00
Ilya Biryukov 4e0c400a47 [clangd] Fix crash due to ObjCPropertyDecl
With ObjCPropertyDecl, ASTNode.OrigD can be a ObjCPropertyImplDecl
which is not a NamedDecl, leading to a crash since the code
incorrectly assumes ASTNode.OrigD will always be a NamedDecl.

Change by dgoldman (David Goldman)!

Differential Revision: https://reviews.llvm.org/D56916

llvm-svn: 351941
2019-01-23 10:35:12 +00:00
George Rimar bcbe98bcb9 [llvm-objdump] - Split disassembleObject() into two methods. NFCI.
Currently, disassembleObject() is a ~550 lines length function.

This patch splits it into two, where first do all helper objects initializations
and calls the second which does all the rest job.
This is a straightforward split.

Differential revision: https://reviews.llvm.org/D57020

llvm-svn: 351940
2019-01-23 10:33:26 +00:00
Jonas Paulsson 6046d087c5 [SystemZ] Fix test case for buildbot.
llvm-clang-x86_64-expensive-checks-win triggered this assert:

"llvm.dbg.value intrinsic requires a !dbg attachment"

Hopefully, adding reasonable !dbg operands solves this.

llvm-svn: 351939
2019-01-23 10:29:12 +00:00
David Green 6a858a9425 [ARM] Alter the register allocation order for minsize on Thumb2
Currently in Arm code, we allocate LR first, under the assumption that
it needs to be saved anyway. Unfortunately this has the disadvantage
that it will require any instructions using it to be the longer thumb2
instructions, not the shorter thumb1 ones.

This switches the order when we are optimising for minsize, returning to
the default order so that more lower registers can be used. It can end
up requiring more pushed registers, but on average produces smaller code.

Differential Revision: https://reviews.llvm.org/D56008

llvm-svn: 351938
2019-01-23 10:18:30 +00:00
Kamil Rytarowski fe1991b55e Mark thread.condition.condvarany/wait_for.pass.cpp as flaky
Reported on the NetBSD 8 buildbot.

llvm-svn: 351937
2019-01-23 10:11:41 +00:00
Dmitry Venikov cce66874a8 [llvm-symbolizer] Allow single letter command flags grouping.
Summary: Currently llvm-symbolizer doesn't allow flags combining. This patch allows such grouping behavior just like addr2line. Motivation: https://bugs.llvm.org/show_bug.cgi?id=40304

Reviewers: jhenderson, ruiu

Reviewed By: jhenderson

Subscribers: rupprecht, llvm-commits

Differential Revision: https://reviews.llvm.org/D57046

llvm-svn: 351936
2019-01-23 09:49:37 +00:00
Sam Parker 31bef63bb4 [ARM][CGP] Check trunc type before replacing
In the last stage of type promotion, we replace any zext that uses a
new trunc with the operand of the trunc. This is okay when we only
allowed one type to be optimised, but now its the case that the trunc
maybe needed to produce a more narrow type than the one we were
optimising for. So we need to check this before doing the replacement.

Differential Revision: https://reviews.llvm.org/D57041

llvm-svn: 351935
2019-01-23 09:18:44 +00:00
Martin Storsjo 8f52c0376b [llvm-objcopy] [COFF] Clear the unwritten tail of coff_section::Header::Name
This should fix the add-gnu-debuglink test on all buildbots.

llvm-svn: 351934
2019-01-23 09:12:53 +00:00
Sam Parker 9a2a89d58f [DAGCombine] Enable more pre-indexed stores
The current check in CombineToPreIndexedLoadStore is too
conversative, preventing a pre-indexed store when the base pointer
is a predecessor of the value being stored. Instead, we should check
the pointer operand of the store.

Differential Revision: https://reviews.llvm.org/D56719

llvm-svn: 351933
2019-01-23 09:11:49 +00:00
Kristof Beyls e70ba0a1bc [SLH][AArch64] Remove accidentally retained -debug-only line from test.
llvm-svn: 351932
2019-01-23 09:10:12 +00:00
Martin Storsjo 12b6b80208 Reapply: [llvm-objcopy] [COFF] Implement --add-gnu-debuglink
This was reverted since it broke a couple buildbots. The reason
for the breakage is not yet known, but this time, the test has
got more diagnostics added, to hopefully allow figuring out
what goes wrong.

Differential Revision: https://reviews.llvm.org/D57007

llvm-svn: 351931
2019-01-23 08:25:28 +00:00
Kristof Beyls 3ff5dfd735 [SLH] AArch64: correctly pick temporary register to mask SP
As part of speculation hardening, the stack pointer gets masked with the
taint register (X16) before a function call or before a function return.
Since there are no instructions that can directly mask writing to the
stack pointer, the stack pointer must first be transferred to another
register, where it can be masked, before that value is transferred back
to the stack pointer.
Before, that temporary register was always picked to be x17, since the
ABI allows clobbering x17 on any function call, resulting in the
following instruction pattern being inserted before function calls and
returns/tail calls:

mov x17, sp
and x17, x17, x16
mov sp, x17
However, x17 can be live in those locations, for example when the call
is an indirect call, using x17 as the target address (blr x17).

To fix this, this patch looks for an available register just before the
call or terminator instruction and uses that.

In the rare case when no register turns out to be available (this
situation is only encountered twice across the whole test-suite), just
insert a full speculation barrier at the start of the basic block where
this occurs.

Differential Revision: https://reviews.llvm.org/D56717

llvm-svn: 351930
2019-01-23 08:18:39 +00:00
Haojian Wu 87b0e3fda9 [clangd] Link clangTidy into clangd tests
Patch by Nathan Ridge!

Differential Revision: https://reviews.llvm.org/D57077

llvm-svn: 351929
2019-01-23 08:04:17 +00:00
Jonas Paulsson 961c47ec98 [SystemZ] Handle DBG_VALUE instructions in two places in backend.
Two backend optimizations failed to handle cases when compiled with -g, due
to failing to consider DBG_VALUE instructions. This was in
SystemZTargetLowering::emitSelect() and
SystemZElimCompare::getRegReferences().

This patch makes sure that DBG_VALUEs are recognized so that they do not
affect these optimizations.

Tests for branch-on-count, load-and-trap and consecutive selects.

Review: Ulrich Weigand
https://reviews.llvm.org/D57048

llvm-svn: 351928
2019-01-23 07:42:26 +00:00
Martin Storsjo b5a5055704 Fix building sanitizers for MinGW
The /EHsc flag is MSVC specific, not generic to the windows target.

llvm-svn: 351927
2019-01-23 07:23:16 +00:00
Max Kazantsev d9aee3c0d1 [IRCE] Support narrow latch condition for wide range checks
This patch relaxes restrictions on types of latch condition and range check.
In current implementation, they should match. This patch allows to handle
wide range checks against narrow condition. The motivating example is the
following:

  int N = ...
  for (long i = 0; (int) i < N; i++) {
    if (i >= length) deopt;
  }

In this patch, the option that enables this support is turned off by
default. We'll wait until it is switched to true.

Differential Revision: https://reviews.llvm.org/D56837
Reviewed By: reames

llvm-svn: 351926
2019-01-23 07:20:56 +00:00
Zinovy Nis 79639e9737 [doc] Fix svn property for bugprone-parent-virtual-call.rst
llvm-svn: 351925
2019-01-23 06:46:27 +00:00
Richard Smith cfa79b27b5 [ubsan] Check the correct size when sanitizing array new.
We previously forgot to multiply the element size by the array bound.

llvm-svn: 351924
2019-01-23 03:37:29 +00:00
Brendon Cahoon 59d9973146 [Pipeliner] Add two pragmas to control software pipelining optimization
#pragma clang loop pipeline(disable)
  
    Disable SWP optimization for the next loop.
    “disable” is the only possible value.
  
#pragma clang loop pipeline_initiation_interval(number)
  
    Set value of initiation interval for SWP
    optimization to specified number value for
    the next loop. Number is the positive value
    greater than 0.
  
These pragmas could be used for debugging or reducing
compile time purposes. It is possible to disable SWP for
concrete loops to save compilation time or to find bugs
by not doing SWP to certain loops. It is possible to set
value of initiation interval to concrete number to save
compilation time by not doing extra pipeliner passes or
to check created schedule for specific initiation interval.

That is llvm part of the fix

Clang part of fix: https://reviews.llvm.org/D55710

Patch by Alexey Lapshin!

Differential Revision: https://reviews.llvm.org/D56403

llvm-svn: 351923
2019-01-23 03:26:10 +00:00
Stephane Moore 05a449b481 Revert rCTE351921 to fix documentation geneeration.
Original review: https://reviews.llvm.org/D56945

llvm-svn: 351922
2019-01-23 02:58:59 +00:00
Stephane Moore be9eca442e [clang-tidy] Delete obsolete objc-property-declaration options ✂️
Summary:
The `Acronyms` and `IncludeDefaultAcronyms` options were deprecated in
https://reviews.llvm.org/D51832. These options can be removed.

Tested by running the clang-tidy tests.

Reviewers: benhamilton, aaron.ballman

Reviewed By: aaron.ballman

Subscribers: Eugene.Zelenko, xazax.hun, cfe-commits

Tags: #clang-tools-extra

Differential Revision: https://reviews.llvm.org/D56945

llvm-svn: 351921
2019-01-23 02:34:21 +00:00
Peter Collingbourne 73078ecd38 hwasan: Move memory access checks into small outlined functions on aarch64.
Each hwasan check requires emitting a small piece of code like this:
https://clang.llvm.org/docs/HardwareAssistedAddressSanitizerDesign.html#memory-accesses

The problem with this is that these code blocks typically bloat code
size significantly.

An obvious solution is to outline these blocks of code. In fact, this
has already been implemented under the -hwasan-instrument-with-calls
flag. However, as currently implemented this has a number of problems:
- The functions use the same calling convention as regular C functions.
  This means that the backend must spill all temporary registers as
  required by the platform's C calling convention, even though the
  check only needs two registers on the hot path.
- The functions take the address to be checked in a fixed register,
  which increases register pressure.
Both of these factors can diminish the code size effect and increase
the performance hit of -hwasan-instrument-with-calls.

The solution that this patch implements is to involve the aarch64
backend in outlining the checks. An intrinsic and pseudo-instruction
are created to represent a hwasan check. The pseudo-instruction
is register allocated like any other instruction, and we allow the
register allocator to select almost any register for the address to
check. A particular combination of (register selection, type of check)
triggers the creation in the backend of a function to handle the check
for specifically that pair. The resulting functions are deduplicated by
the linker. The pseudo-instruction (really the function) is specified
to preserve all registers except for the registers that the AAPCS
specifies may be clobbered by a call.

To measure the code size and performance effect of this change, I
took a number of measurements using Chromium for Android on aarch64,
comparing a browser with inlined checks (the baseline) against a
browser with outlined checks.

Code size: Size of .text decreases from 243897420 to 171619972 bytes,
or a 30% decrease.

Performance: Using Chromium's blink_perf.layout microbenchmarks I
measured a median performance regression of 6.24%.

The fact that a perf/size tradeoff is evident here suggests that
we might want to make the new behaviour conditional on -Os/-Oz.
But for now I've enabled it unconditionally, my reasoning being that
hwasan users typically expect a relatively large perf hit, and ~6%
isn't really adding much. We may want to revisit this decision in
the future, though.

I also tried experimenting with varying the number of registers
selectable by the hwasan check pseudo-instruction (which would result
in fewer variants being created), on the hypothesis that creating
fewer variants of the function would expose another perf/size tradeoff
by reducing icache pressure from the check functions at the cost of
register pressure. Although I did observe a code size increase with
fewer registers, I did not observe a strong correlation between the
number of registers and the performance of the resulting browser on the
microbenchmarks, so I conclude that we might as well use ~all registers
to get the maximum code size improvement. My results are below:

Regs | .text size | Perf hit
-----+------------+---------
~all | 171619972  | 6.24%
  16 | 171765192  | 7.03%
   8 | 172917788  | 5.82%
   4 | 177054016  | 6.89%

Differential Revision: https://reviews.llvm.org/D56954

llvm-svn: 351920
2019-01-23 02:20:10 +00:00
Peter Collingbourne 7cf27205df gn build: Merge r351820.
llvm-svn: 351919
2019-01-23 02:19:56 +00:00