Chris Bieneman [Tue, 11 Jun 2019 00:25:57 +0000 (00:25 +0000)]
Setup testing target dependencies for default runtimes
Summary: The default runtimes targets aren't getting their dependencies configured correctly which results in check-runtimes failing when built from a clean build.
Puyan Lotfi [Tue, 11 Jun 2019 00:00:25 +0000 (00:00 +0000)]
[MIR-Canon] Fixing non-determinism that was breaking bots (NFC).
An earlier fix of a subtle iterator invalidation bug had uncovered a
nondeterminism that was present in the MultiUsers bag. Problem was that
MultiUsers was being looked up using pointers.
This patch is an NFC change that numbers each multiuser and processes each in
numbered order. This fixes the test failure on netbsd and will likely fix the
green-dragon bot too.
Previous detection relied upon an arbitrary hard coded limit of 21
response files, which some code bases were running up against.
The new detection maintains a stack of processing response files and
explicitly checks if a newly encountered file is in the current stack.
Some bookkeeping data is necessary in order to detect when to pop the
stack.
Philip Reames [Mon, 10 Jun 2019 23:17:10 +0000 (23:17 +0000)]
[Tests] Adjust LFTR dead-iv tests to bypass undef cases
As pointed out by Nikita in review, undef and poison need to be handled separately. Since we're no longer expecting any test improvements - just fixes for miscompiles - update the tests to bypass the existing undef check.
Rong Xu [Mon, 10 Jun 2019 22:36:27 +0000 (22:36 +0000)]
[PGO] Handle cases of non-instrument BBs
As shown in PR41279, some basic blocks (such as catchswitch) cannot be
instrumented. This patch filters out these BBs in PGO instrumentation.
It also sets the profile count to the fail-to-instrument edge, so that we
can propagate the counts in the CFG.
Philip Reames [Mon, 10 Jun 2019 22:33:20 +0000 (22:33 +0000)]
[Tests] Split an LFTR dead-iv case
There are two interesting sub-cases here. 1) Switching IVs is legal, but only in pre-increment form. and 2) Switching IVs is legal, and so is post-increment form.
Tom Stellard [Mon, 10 Jun 2019 22:12:56 +0000 (22:12 +0000)]
CMake: Make most target symbols hidden by default
Summary:
For builds with LLVM_BUILD_LLVM_DYLIB=ON and BUILD_SHARED_LIBS=OFF
this change makes all symbols in the target specific libraries hidden
by default.
A new macro called LLVM_EXTERNAL_VISIBILITY has been added to mark symbols in these
libraries public, which is mainly needed for the definitions of the
LLVMInitialize* functions.
This patch reduces the number of public symbols in libLLVM.so by about
25%. This should improve load times for the dynamic library and also
make abi checker tools, like abidiff require less memory when analyzing
libLLVM.so
One side-effect of this change is that for builds with
LLVM_BUILD_LLVM_DYLIB=ON and LLVM_LINK_LLVM_DYLIB=ON some unittests that
access symbols that are no longer public will need to be statically linked.
Before and after public symbol counts (using gcc 8.2.1, ld.bfd 2.31.1):
nm before/libLLVM-9svn.so | grep ' [A-Zuvw] ' | wc -l
36221
nm after/libLLVM-9svn.so | grep ' [A-Zuvw] ' | wc -l
26278
Philip Reames [Mon, 10 Jun 2019 19:45:59 +0000 (19:45 +0000)]
[Tests] Add tests for D62939 (miscompiles around dead pointer IVs)
Flesh out a collection of tests for switching to a dead IV within LFTR, both for the current miscompile, and for some cases which we should be able to handle via simple reasoning.
Philip Reames [Mon, 10 Jun 2019 19:18:53 +0000 (19:18 +0000)]
[LFTR] Use recomputed BE count
This was discussed as part of D62880. The basic thought is that computing BE taken count after widening should produce (on average) an equally good backedge taken count as the one before widening. Since there's only one test in the suite which is impacted by this change, and it's essentially equivelent codegen, that seems to be a reasonable assertion. This change was separated from r362971 so that if this turns out to be problematic, the triggering piece is obvious and easily revertable.
For the nestedIV example from elim-extend.ll, we end up with the following BE counts:
BEFORE: (-2 + (-1 * %innercount) + %limit)
AFTER: (-1 + (sext i32 (-1 + %limit) to i64) + (-1 * (sext i32 %innercount to i64))<nsw>)
Note that before is an i32 type, and the after is an i64. Truncating the i64 produces the i32.
Jordan Rupprecht [Mon, 10 Jun 2019 18:35:01 +0000 (18:35 +0000)]
[llvm-objcopy] Fix SHT_GROUP ordering.
Summary:
When llvm-objcopy sorts sections during finalization, it only sorts based on the offset, which can cause the group section to come after the sections it contains. This causes link failures when using gold to link objects created by llvm-objcopy.
Fix this for now by copying GNU objcopy's behavior of placing SHT_GROUP sections first. In the future, we may want to remove this sorting entirely to more closely preserve the input file layout.
This fixes https://bugs.llvm.org/show_bug.cgi?id=42052.
Philip Reames [Mon, 10 Jun 2019 17:51:13 +0000 (17:51 +0000)]
Prepare for multi-exit LFTR [NFC]
This change does the plumbing to wire an ExitingBB parameter through the LFTR implementation, and reorganizes the code to work in terms of a set of individual loop exits. Most of it is fairly obvious, but there's one key complexity which makes it worthy of consideration. The actual multi-exit LFTR patch is in D62625 for context.
Specifically, it turns out the existing code uses the backedge taken count from before a IV is widened. Oddly, we can end up with a different (more expensive, but semantically equivelent) BE count for the loop when requerying after widening. For the nestedIV example from elim-extend, we end up with the following BE counts:
BEFORE: (-2 + (-1 * %innercount) + %limit)
AFTER: (-1 + (sext i32 (-1 + %limit) to i64) + (-1 * (sext i32 %innercount to i64))<nsw>)
This is the only test in tree which seems sensitive to this difference. The actual result of using the wider BETC on this example is that we actually produce slightly better code. :)
In review, we decided to accept that test change. This patch is structured to preserve the old behavior, but a separate change will immediate follow with the behavior change. (I wanted it separate for problem attribution purposes.)
Andrea Di Biagio [Mon, 10 Jun 2019 16:56:25 +0000 (16:56 +0000)]
[llvm-mca] Enable bottleneck analysis when flag -all-views is specified.
Bottleneck Analysis is one of the many views available in llvm-mca. Therefore,
it should be enabled when flag -all-views is passed in input to the tool.
[FastISel] Skip creating unnecessary vregs for arguments
This behavior was added in r130928 for both FastISel and SD, and then
disabled in r131156 for FastISel.
This re-enables it for FastISel with the corresponding fix.
This is triggered only when FastISel can't lower the arguments and falls
back to SelectionDAG for it.
FastISel contains a map of "register fixups" where at the end of the
selection phase it replaces all uses of a register with another
register that FastISel sometimes pre-assigned. Code at the end of
SelectionDAGISel::runOnMachineFunction is doing the replacement at the
very end of the function, while other pieces that come in before that
look through the MachineFunction and assume everything is done. In this
case, the real issue is that the code emitting COPY instructions for the
liveins (physreg to vreg) (EmitLiveInCopies) is checking if the vreg
assigned to the physreg is used, and if it's not, it will skip the COPY.
If a register wasn't replaced with its assigned fixup yet, the copy will
be skipped and we'll end up with uses of undefined registers.
This fix moves the replacement of registers before the emission of
copies for the live-ins.
The initial motivation for this fix is to enable tail calls for
swiftself functions, which were blocked because we couldn't prove that
the swiftself argument (which is callee-save) comes from a function
argument (live-in), because there was an extra copy (vreg to vreg).
A few tests are affected by this:
* llvm/test/CodeGen/AArch64/swifterror.ll: we used to spill x21
(callee-save) but never reload it because it's attached to the return.
We now don't even spill it anymore.
* llvm/test/CodeGen/*/swiftself.ll: we tail-call now.
* llvm/test/CodeGen/AMDGPU/mubuf-legalize-operands.ll: I believe this
test was not really testing the right thing, but it worked because the
same registers were re-used.
* llvm/test/CodeGen/ARM/cmpxchg-O0.ll: regalloc changes
* llvm/test/CodeGen/ARM/swifterror.ll: get rid of a copy
* llvm/test/CodeGen/Mips/*: get rid of spills and copies
* llvm/test/CodeGen/SystemZ/swift-return.ll: smaller stack
* llvm/test/CodeGen/X86/atomic-unordered.ll: smaller stack
* llvm/test/CodeGen/X86/swifterror.ll: same as AArch64
* llvm/test/DebugInfo/X86/dbg-declare-arg.ll: stack size changed
Simon Tatham [Mon, 10 Jun 2019 15:36:34 +0000 (15:36 +0000)]
[ARM] Add the non-MVE instructions in Arm v8.1-M.
This adds support for the new family of conditional selection /
increment / negation instructions; the low-overhead branch
instructions (e.g. BF, WLS, DLS); the CLRM instruction to zero a whole
list of registers at once; the new VMRS/VMSR and VLDR/VSTR
instructions to get data in and out of 8.1-M system registers,
particularly including the new VPR register used by MVE vector
predication.
To support this, we also add a register name 'zr' (used by the CSEL
family to force one of the inputs to the constant 0), and operand
types for lists of registers that are also allowed to include APSR or
VPR (used by CLRM). The VLDR/VSTR instructions also need some new
addressing modes.
The low-overhead branch instructions exist in their own separate
architecture extension, which we treat as enabled by default, but you
can say -mattr=-lob or equivalent to turn it off.
Whitney Tsang [Mon, 10 Jun 2019 15:29:07 +0000 (15:29 +0000)]
[DA] Add an option to control delinearization validity checks
Summary: Dependence Analysis performs static checks to confirm validity
of delinearization. These checks often fail for 64-bit targets due to
type conversions and integer wrapping that prevent simplification of the
SCEV expressions. These checks would also fail at compile-time if the
lower bound of the loops are compile-time unknown.
Author: bmahjour
Reviewer: Meinersbur, jdoerfert, kbarton, dmgreen, fhahn
Reviewed By: Meinersbur, jdoerfert, dmgreen
Subscribers: fhahn, hiraditya, javed.absar, llvm-commits, Whitney,
etiotto
Tag: LLVM
Differential Revision: https://reviews.llvm.org/D62610
Jeremy Morse [Mon, 10 Jun 2019 15:23:46 +0000 (15:23 +0000)]
[DebugInfo] Terminate all location-lists at end of block
This commit reapplies r359426 (which was reverted in r360301 due to
performance problems) and rolls in D61940 to address the performance problem.
I've combined the two to avoid creating a span of slow-performance, and to
ease reverting if more problems crop up.
The summary of D61940: This patch removes the "ChangingRegs" facility in
DbgEntityHistoryCalculator, as its overapproximate nature can produce incorrect
variable locations. An unchanging register doesn't mean a variable doesn't
change its location.
The patch kills off everything that calculates the ChangingRegs vector.
Previously ChangingRegs spotted epilogues and marked registers as unchanging if
they weren't modified outside the epilogue, increasing the chance that we can
emit a single-location variable record. Without this feature,
debug-loc-offset.mir and pr19307.mir become temporarily XFAIL. They'll be
re-enabled by D62314, using the FrameDestroy flag to identify epilogues, I've
split this into two steps as FrameDestroy isn't necessarily supported by all
backends.
The logic for terminating variable locations at the end of a basic block now
becomes much more enjoyably simple: we just terminate them all.
Other test changes: inlined-argument.ll becomes XFAIL, but for a longer term.
The current algorithm for detecting that a variable has a single-location
doesn't work in this scenario (inlined function in multiple blocks), only other
bugs were making this test work. fission-ranges.ll gets slightly refreshed too,
as the location of "p" is now correctly determined to be a single location.
Sanjay Patel [Mon, 10 Jun 2019 14:46:36 +0000 (14:46 +0000)]
[InstCombine] change canonicalization to fabs() to use FMF on fsub
Similar to rL362909:
This isn't the ideal fix (use FMF on the select), but it's still an
improvement until we have better FMF propagation to selects and other
FP math operators.
I don't think there's much risk of regression from this change by
not including the FMF on the fcmp any more. The nsz/nnan FMF
should be the same on the fcmp and the fsub because they have the
same operand.
Simon Tatham [Mon, 10 Jun 2019 14:43:55 +0000 (14:43 +0000)]
[ARM] Disallow PC, and optionally SP, in VMOVRH and VMOVHR.
Arm v8.1-M supports the VMOV instructions that move a half-precision
value to and from a GPR, but not if the GPR is SP or PC.
To fix this, I've changed those instructions to use the rGPR register
class instead of GPR. rGPR always excludes PC, and it excludes SP
except in the presence of the HasV8Ops target feature (i.e. Arm v8-A).
So the effect is that VMOV.F16 to and from PC is now illegal
everywhere, but VMOV.F16 to and from SP is illegal only on non-v8-A
cores (which I believe is all as it should be).
George Rimar [Mon, 10 Jun 2019 12:43:18 +0000 (12:43 +0000)]
[yaml2obj/obj2yaml] - Make RawContentSection::Content and RawContentSection::Size optional
This is a follow-up for D62809.
Content and Size fields should be optional as was discussed in comments
of the D62809's thread. With that, we can describe a specific string table and
symbol table sections in a more correct way and also show appropriate errors.
The patch adds lots of test cases where the behavior is described in details.
George Rimar [Mon, 10 Jun 2019 11:38:06 +0000 (11:38 +0000)]
[yaml2obj] - Do not assert when .dynsym is specified explicitly, but .dynstr is not present.
We have a code in buildSectionIndex() that adds implicit sections:
// Add special sections after input sections, if necessary.
for (StringRef Name : implicitSectionNames())
if (SN2I.addName(Name, SecNo)) {
// Account for this section, since it wasn't in the Doc
++SecNo;
DotShStrtab.add(Name);
}
The problem arises when .dynsym is specified explicitly and no
DynamicSymbols is used. In that case, we do not add
.dynstr implicitly and will assert later when will try to set Link
for .dynsym.
Seems, in this case, reasonable behavior is to allow Link field to be zero.
This is what this patch does.
David Green [Mon, 10 Jun 2019 10:22:14 +0000 (10:22 +0000)]
[ARM] Enable Unroll UpperBound
This option allows loops with small max trip counts to be fully unrolled. This
can help with code like the remainder loops from manually unrolled loops like
those that appear in the cmsis dsp library. We would apparently previously
runtime unroll them with the default unroll count (4).
Nikola Prica [Mon, 10 Jun 2019 08:41:06 +0000 (08:41 +0000)]
[DebugInfo] More strict debug range for stack variables
Variable's stack location can stretch longer than it should. If a
variable is placed at the stack in a some nested basic block its range
can be calculated to be up to the next occurrence of the variable's
DBG_VALUE, or up to the end of the function, thus covering a basic
blocks that should not be included in the variable’s location range.
This happens because the DbgEntityHistoryCalculator ends register
locations at the end of a basic block only if the variable’s location
register has been changed throughout the function, which is not the
case for the register used to reference stack objects.
This patch also tries to produce a single value location if the location
list builder managed to merge all the locations into one.
QingShan Zhang [Mon, 10 Jun 2019 05:40:21 +0000 (05:40 +0000)]
[DAGCombine] Match a pattern where a wide type scalar value is stored by several narrow stores
This opportunity is found from spec 2017 557.xz_r. And it is used by the sha encrypt/decrypt. See sha-2/sha512.c
static u64 load64(const unsigned char* y)
{
u64 res = 0;
for(int i = 0; i != 8; ++i)
res |= (u64)(y[i]) << ((7-i) * 8);
return res;
}
The load64 has been implemented by https://reviews.llvm.org/D26149
This patch is trying to implement the store pattern.
Match a pattern where a wide type scalar value is stored by several narrow
stores. Fold it into a single store or a BSWAP and a store if the targets
supports it.
Craig Topper [Mon, 10 Jun 2019 04:50:12 +0000 (04:50 +0000)]
[X86] When promoting i16 compare with immediate to i32, try to use sign_extend for eq/ne if the input is truncated from a type with enough sign its.
Summary:
Our default behavior is to use sign_extend for signed comparisons and zero_extend for everything else. But for equality we have the freedom to use either extension. If we can prove the input has been truncated from something with enough sign bits, we can use sign_extend instead and let DAG combine optimize it out. A similar rule is used by type legalization in LegalizeIntegerTypes.
This gets rid of the movzx in PR42189. The immediate will still take 4 bytes instead of the 2 bytes plus 0x66 prefix a cmp di, 32767 would get, but it avoids a length changing prefix.
Craig Topper [Mon, 10 Jun 2019 04:37:16 +0000 (04:37 +0000)]
[X86] Disable f32->f64 extload when sse2 is enabled
Summary:
We can only use the memory form of cvtss2sd under optsize due to a partial register update. So previously we were emitting 2 instructions for extload when optimizing for speed. Also due to a late optimization in preprocessiseldag we had to handle (fpextend (loadf32)) under optsize.
This patch forces extload to expand so that it will always be in the (fpextend (loadf32)) form during isel. And when optimizing for speed we can just let each of those pieces select an instruction independently.
Craig Topper [Mon, 10 Jun 2019 00:41:07 +0000 (00:41 +0000)]
[X86] Convert f32/f64 FANDN/FAND/FOR/FXOR to vector logic ops and scalar_to_vector/extract_vector_elts to reduce isel patterns.
Previously we did the equivalent operation in isel patterns with
COPY_TO_REGCLASS operations to transition. By inserting
scalar_to_vetors and extract_vector_elts before isel we can
allow each piece to be selected individually and accomplish the
same final result.
I ideally we'd use vector operations earlier in lowering/combine,
but that looks to be more difficult.
The scalar-fp-to-i64.ll changes are because we have a pattern for
using movlpd for store+extract_vector_elt. While an f64 store
uses movsd. The encoding sizes are the same.
Roman Lebedev [Sun, 9 Jun 2019 16:30:14 +0000 (16:30 +0000)]
[NFC][InstCombine] Revisit canonicalize-constant-low-bit-mask-and-icmp-s* tests in preparatio for PR42198.
The `icmp sgt`/`icmp sle` variants are, too, miscompiles:
https://rise4fun.com/Alive/JFNP
https://rise4fun.com/Alive/jHvL
A precondition 'x != 0' was forgotten by me.
While ensuring test coverage for `-1`, also add test coverage
for `0` mask. Mask `0` is allowed for all the folds,
mask `-1` is allowed for all the folds with unsigned `icmp` pred.
Constant mask `0` is missed though.
Sanjay Patel [Sun, 9 Jun 2019 16:22:01 +0000 (16:22 +0000)]
[InstCombine] change canonicalization to fabs() to use FMF on fneg
This isn't the ideal fix (use FMF on the select), but it's still an
improvement until we have better FMF propagation to selects and other
FP math operators.
I don't think there's much risk of regression from this change by
not including the FMF on the fcmp any more. The nsz/nnan FMF
should be the same on the fcmp and the fneg (fsub) because they
have the same operand.
This works around the most glaring FMF logical inconsistency cited
in PR38086:
https://bugs.llvm.org/show_bug.cgi?id=38086
Sanjay Patel [Sun, 9 Jun 2019 13:48:59 +0000 (13:48 +0000)]
[InstSimplify] enhance fcmp fold with never-nan operand
This is another step towards correcting our usage of fast-math-flags when applied on an fcmp.
In this case, we are checking for 'nnan' on the fcmp itself rather than the operand of
the fcmp. But I'm leaving that clause in until we're more confident that we can stop
relying on fcmp's FMF.
By using the more general "isKnownNeverNaN()", we gain a simplification shown on the
tests with 'uitofp' regardless of the FMF on the fcmp (uitofp never produces a NaN).
On the tests with 'fabs', we are now relying on the FMF for the call fabs instruction
in addition to the FMF on the fcmp.
Anton Afanasyev [Sun, 9 Jun 2019 12:15:47 +0000 (12:15 +0000)]
[MIR] Add simple PRE pass to MachineCSE
This is the second part of the commit fixing PR38917 (hoisting
partitially redundant machine instruction). Most of PRE (partitial
redundancy elimination) and CSE work is done on LLVM IR, but some of
redundancy arises during DAG legalization. Machine CSE is not enough
to deal with it. This simple PRE implementation works a little bit
intricately: it passes before CSE, looking for partitial redundancy
and transforming it to fully redundancy, anticipating that the next
CSE step will eliminate this created redundancy. If CSE doesn't
eliminate this, than created instruction will remain dead and eliminated
later by Remove Dead Machine Instructions pass.
The third part of the commit is supposed to refactor MachineCSE,
to make it more clear and to merge MachinePRE with MachineCSE,
so one need no rely on further Remove Dead pass to clear instrs
not eliminated by CSE.
First step: https://reviews.llvm.org/D54839
Fixes llvm.org/PR38917
This is fixed recommit of r361356 after PowerPC64 multistage build failure.
[CaptureTracking] Don't let comparisons against null escape inbounds pointers
Pointers that are in-bounds (either through dereferenceable_or_null or
thorough a getelementptr inbounds) cannot be captured with a comparison
against null. There is no way to construct a pointer that is still in
bounds but also NULL.
This helps safe languages that insert null checks before load/store
instructions. Without this patch, almost all pointers would be
considered captured even for simple loads. With this patch, an icmp with
null will not be seen as escaping as long as certain conditions are met.
There was a lot of discussion about this patch. See the Phabricator
thread for detals.
Sanjay Patel [Sat, 8 Jun 2019 15:12:33 +0000 (15:12 +0000)]
[InstSimplify] enhance fcmp fold with never-nan operand
This is 1 step towards correcting our usage of fast-math-flags when applied on an fcmp.
In this case, we are checking for 'nnan' on the fcmp itself rather than the operand of
the fcmp. But I'm leaving that clause in until we're more confident that we can stop
relying on fcmp's FMF.
By using the more general "isKnownNeverNaN()", we gain a simplification shown on the
tests with 'uitofp' regardless of the FMF on the fcmp (uitofp never produces a NaN).
On the tests with 'fabs', we are now relying on the FMF for the call fabs instruction
in addition to the FMF on the fcmp.
I'll update the 'ult' case below here as a follow-up assuming no problems here.
David Green [Sat, 8 Jun 2019 10:32:53 +0000 (10:32 +0000)]
[ARM] Adjust isLegalT1AddressImmediate for non-legal types
Types such as float and i64's do not have legal loads in Thumb1, but will still
be loaded with a LDR (or potentially multiple LDR's). As such we can treat the
cost of addressing mode calculations the same as an i32 and get some optimisation
benefits.
David Green [Sat, 8 Jun 2019 10:18:23 +0000 (10:18 +0000)]
[ARM] Add MVE addressing to isLegalT2AddressImmediate
Now with MVE being added, we can add the vector addressing mode costs for it.
These are generally imm7 multiplied by the size of the type being loaded /
stored.
David Green [Sat, 8 Jun 2019 10:09:02 +0000 (10:09 +0000)]
[ARM] Add fp16 addressing to isLegalT2AddressImmediate
The fp16 version of VLDR takes a imm8 multiplied by 2. This updates the costs
to account for those, and adds extra testing. It is dependant upon hasFPRegs16
as this is what the load/store instructions require.