xorl + setcc is generally the preferred sequence due to the partial register
stall setcc + movzbl suffers from. As a bonus, it also encodes one byte smaller.
This fixes PR28146.
The original commit tried inserting an 8bit-subreg into a GR32 (not GR32_ABCD)
which was not appreciated by fast regalloc on 32-bit.
GCOVProfiler::emitProfileArcs() can create many variables with names
starting with "__llvm_gcov_ctr", so llvm appends a numeric suffix to
most of them. Teach tsan about this.
ThinLTO: Do not take into account whether a definition has multiple copies when promoting.
We currently do not touch a symbol's linkage in the case where a definition
has a single copy. However, this code is effectively unnecessary: either
the definition is not exported, in which case the internalize phase sets
its linkage to internal, or it is exported, in which case we need to promote
linkage to weak. Those two cases are already handled by existing code.
I believe that the only real functional change here is in the case where we
have a single definition which does not prevail (e.g. because the definition
in a native object file prevails). In that case we now lower linkage to
available_externally following the existing code path for that case.
As a result we can remove the isExported function parameter from the
thinLTOResolveWeakForLinkerInIndex function.
Dan Liew [Thu, 7 Jul 2016 18:14:11 +0000 (18:14 +0000)]
[LibFuzzer] Unbreak the build on macOS which was broken by r272858.
``afl_driver.cpp`` currently relies on weak symbols which doesn't
work properly under macOS. For now fix the build by providing a
dummy implementation of ``LLVMFuzzerInitialize(...)``. This is just
a temporary measure until we fix ``afl_driver.cpp`` for macOS.
- Rename the ptx.read.* intrinsics to nvvm.read.ptx.sreg.* - some but
not all of these registers were already accessible via the nvvm
name.
- Rename ptx.bar.sync nvvm.bar.sync, to match nvvm.bar0.
There's a fair amount of code motion here, but it's all very
mechanical.
[SystemZ] Fix regression when handling conditional calls
Summary:
A regression showed up in node.js when handling conditional calls.
Fix the regression by recognizing external symbols as a possible
operand type in CallJG.
Code size optimisation: don't rewrite fputs to fwrite when optimising for size
because fwrite requires more arguments and thus extra MOVs are required.
[ARM] Do not test for CPUs, use SubtargetFeatures. Also remove 1 flag
This is a follow-up for r273544.
The end goal is to get rid of the isSwift / isCortexXY / isWhatever methods.
This commit also removes a command line flag that isn't used in any of the tests:
check-vmlx-hazards. It can be replaced easily with the mattr mechanism, since
this is now a subtarget feature.
There is still some work left regarding FeatureExpandMLx. In the past MLx
expansion was enabled for subtargets with hasVFP2(), until r129775 [1] switched
from that to isCortexA9, without too much justification.
In spite of that, the code performing MLx expansion still contains calls to
isSwift/isLikeA9, although the results of those are pretty clear given that
we're only enabling it for the A9.
We should try to enable it for all targets that have FeatureHasVMLxHazards, as
it seems to be closely related to that behaviour, and if that is possible try to
clean up the MLx expansion pass from all calls to isWhatever. This will require
some performance testing, so it will be done in another patch.
[LCG] Hoist the definitions of the stream operator friends to be inline
friend definitions.
Based on the experiments Sean Silva and Reid did, this seems the safest
course of action and also will work around a questionable warning
provided by GCC6 on the old form of the code. Thanks for Davide pointing
out the issue and other suggesting ways to fix.
[AVX512] Zero extend the result of vpcmpeq/vpcmpgt and similar intrinsics in the autoupgrade code. This currently results in worse codegen but is needed for correctness.
ThinLTO: Remove check for multiple modules before applying weak resolutions.
This check is not only unnecessary, it can produce the wrong result. If we
are linking a single module and it has an exported linkonce symbol, we need
to promote to weak in order to avoid PR19901-style problems.
xorl + setcc is generally the preferred sequence due to the partial register
stall setcc + movzbl suffers from. As a bonus, it also encodes one byte smaller.
On CPUs with the zero cycle zeroing feature enabled "movi v.2d" should
be used to zero a vector register. This was previously done at
instruction selection time, however the register coalescer sometimes
widened multiple vregs to the Q width because of that leading to extra
spills. This patch leaves the decision on how to zero a register to the
AsmPrinter phase where it doesn't affect register allocation anymore.
This patch also sets isAsCheapAsAMove=1 on FMOVS0, FMOVD0.
This fixes http://llvm.org/PR27454, rdar://25866262
AArch64: Replace a RegScavenger instance with LivePhysRegs
findScratchNonCalleeSaveRegister() just needs a simple liveness
analysis, use LivePhysRegs for that as it is simpler and does not depend
on the kill flags.
This commit adds a convenience function available() to LivePhysRegs:
This function returns true if the given register is not reserved and
neither the register nor any of its aliases are alive.
[InstCombine] use more specific pattern matchers; NFCI
Follow-up from r274465: we don't need to capture the value in these cases,
so just match the constant that we're looking for. m_One/m_Zero work with
vector splats as well as scalars.
Piotr Padlewski [Wed, 6 Jul 2016 20:26:25 +0000 (20:26 +0000)]
Add 'thinlto_src_module' metadata to imported function
Added metadata to be able to make statistics on how many functions
that have been imported have been removed. Also module name might
be helpfull when debugging.
Chad Rosier [Wed, 6 Jul 2016 19:48:52 +0000 (19:48 +0000)]
[DSE] Avoid iterator invalidation bugs.
The dse_with_dbg_value.ll test committed with r273141 is removed because this
we no longer performs any type of back tracking, which is what was causing the
codegen differences with and without debug information.
Paul Robinson [Wed, 6 Jul 2016 19:32:41 +0000 (19:32 +0000)]
[Conduct] Refine what "rare cases" means wrt violations outside our spaces.
Text suggested by Daniel Berlin. While it is likely to be exactly what
the advisory committee would do anyway, codifying it does no harm and
helps reassure people that rare does not mean arbitrary.
[x86] fix cost of SINT_TO_FP for i32 --> float (PR21356, PR28434)
This is "cvtdq2ps" which does not appear to be particularly slow on any CPU
according to Agner's tables. Choosing "5" as a cost here as suggested in:
https://llvm.org/bugs/show_bug.cgi?id=21356
...but it seems very conservative given that the instruction is fully pipelined,
and I think these costs are supposed to model throughput.
Note that related costs are also most likely too high, but this fixes PR21356
and partly fixes PR28434.
This logic was introduced in r157663 and does not make any sense to me.
The motivating example in rdar://11538365 looks like this:
This is the tail:
BB#16: derived from LLVM BB %if.end68
Live Ins: %R0 %R4 %R5
Predecessors according to CFG: BB#15 BB#5
tBLXi pred:14, pred:%noreg, <ga:@CFRelease>, %R0<kill>, <regmask>, %LR<imp-def,dead>, %SP<imp-use>, %SP<imp-def>
t2B <BB#20>, pred:14, pred:%noreg
Successors according to CFG: BB#20
This is the predBB:
BB#5:
Live Ins: %R5
Predecessors according to CFG: BB#4
%R4<def> = t2MOVi 0, pred:14, pred:%noreg, opt:%noreg
t2B <BB#16>, pred:14, pred:%noreg
Successors according to CFG: BB#16
However this is invalid machine code to begin with, if %R0 is live-in to
BB#16 then it must be live-in to BB#5 as well if BB#5 does not define
it. We should not need logic to retroactively fix broken machine code
and in fact the example from r157663 passes cleanly with the code
removed and I do not see any (newly) failing tests with the machine
verifier enabled.
[SystemZ] Remove AND mask of bottom 6 bits when result is used for shift/rotate
On SystemZ, shift and rotate instructions only use the bottom 6 bits of the shift/rotate amount.
Therefore, if the amount is ANDed with an immediate mask that has all of the bottom 6 bits set, we
can remove the AND operation entirely.
Simon Pilgrim [Wed, 6 Jul 2016 18:09:08 +0000 (18:09 +0000)]
[X86][SSE] Fixed typo in insertps lowering.
We were checking for 2 insertions (which is caught earlier in the pattern matching loop) instead of the case where we have no insertions.
Turns out this code never fires as we always try to lower to insertps after trying to lower to blendps, which would catch these cases - I'm about to make some changes to support combining to insertps which could cause this to fire so I don't want to remove it.
Ensure all uses of permute instructions feed vector stores
There is a problem in VSXSwapRemoval where it is incorrectly removing permute instructions.
In this case, the permute is feeding both a vector store and also a non-store instruction. In this case, the permute cannot be removed.
The fix is to simply look at all the uses of the vector register defined by the permute and ensure that all the uses are vector store instructions.
This problem was reported in PR 27735 (https://llvm.org/bugs/show_bug.cgi?id=27735).
Tim Shen [Wed, 6 Jul 2016 17:44:03 +0000 (17:44 +0000)]
[DAGCombiner] Fix visitSTORE to continue processing current SDNode, if findBetterNeighborChains doesn't actually CombineTo it.
Summary:
findBetterNeighborChains may or may not find a better chain for each node it finds, which include the node ("St") that visitSTORE is currently processing. If no better chain is found for St, visitSTORE should continue instead of return SDValue(St, 0), as if it's CombinedTo'ed.
This fixes bug 28130. There might be other ways to make the test pass (see D21409). I think both of the patches are fixing actual bugs revealed by the same testcase.
[TTI] The cost model should not assume vector casts get completely scalarized
The cost model should not assume vector casts get completely scalarized, since
on targets that have vector support, the common case is a partial split up to
the legal vector size. So, when a vector cast gets split, the resulting casts
end up legal and cheap.
Instead of pessimistically assuming scalarization, base TTI can use the costs
the concrete TTI provides for the split vector, plus a fudge factor to account
for the cost of the split itself. This fudge factor is currently 1 by default,
except on AMDGPU where inserts and extracts are considered free.
Matthew Simpson [Wed, 6 Jul 2016 14:26:59 +0000 (14:26 +0000)]
[LV] Don't widen trivial induction variables
We currently always vectorize induction variables. However, if an induction
variable is only used for counting loop iterations or computing addresses with
getelementptr instructions, we don't need to do this. Vectorizing these trivial
induction variables can create vector code that is difficult to simplify later
on. This is especially true when the unroll factor is greater than one, and we
create vector arithmetic when computing step vectors. With this patch, we check
if an induction variable is only used for counting iterations or computing
addresses, and if so, scalarize the arithmetic when computing step vectors
instead. This allows for greater simplification.
This patch addresses the suboptimal pointer arithmetic sequence seen in
PR27881.
[ARM] Do not test for CPUs, use SubtargetFeatures. Also remove 2 flags.
This is a follow-up for r273544.
The end goal is to get rid of the isSwift / isCortexXY / isWhatever methods.
This commit also removes two command-line flags that weren't used in any of the
tests: widen-vmovs and swift-partial-update-clearance. The former may be easily
replaced with the mattr mechanism, but the latter may not (as it is a subtarget
property, and not a proper feature).
AVX-512: Optimization for patterns with i1 scalar type
The patch removes redundant kmov instructions (not all, we still have a lot of work here) and redundant "and" instructions after "setcc".
I use "AssertZero" marker between X86ISD::SETCC node and "truncate" to eliminate extra "and $1" instruction.
I also changed zext, aext and trunc patterns in the .td file. It allows to remove extra "kmov" instruictions.
This patch fixes https://llvm.org/bugs/show_bug.cgi?id=28173.
Fast ISEL mode is not supported correctly for AVX-512. ICMP/FCMP scalar instruction should return result in k-reg. It will be fixed in one of the next patches. I redirected handling of "cmp" to the DAG builder mode. (The code looks worse in one specific test case, but without this fix the new patch fails).
Summary:
Since "AMDGPU: Fix verifier errors in SILowerControlFlow", the logic that
ensures that a non-void-returning shader falls off the end of the last
basic block was effectively disabled, since SI_RETURN is now used.