Commit Graph

911 Commits

Author SHA1 Message Date
Simon Pilgrim 06ea4be281 [DAGCombiner] Fix PR25763 - vector comparison constant folding + sign-extension
PR25763 demonstrated an issue with D14683 - vector comparison constant folding only works for i1 results, so we need to split off the sign-extension of the result to the required type. Luckily this can be done with the existing type legalization code.

llvm-svn: 255289
2015-12-10 19:47:06 +00:00
Pirama Arumuga Nainar 1317d5f311 Fix fptosi, fptoui from f16 vectors to i8, i16 vectors
Summary:
Convert f16 vectors to corresponding f32 vectors before doing the
conversion to int.

Add tests for v4f16, v8f16.

Reviewers: ab, jmolloy

Subscribers: llvm-commits, srhines

Differential Revision: http://reviews.llvm.org/D14936

llvm-svn: 255263
2015-12-10 17:16:49 +00:00
Ahmed Bougacha 97564c3a1b [AArch64][ARM] Don't base interleaved op legality on type alloc size.
Otherwise, we think that most types that look like they'd fit in a
legal vector type are legal (so, basically, *any* vector type with a
size between 33 and 128 bits, I think, since we use pow2 alignment;
e.g., v2i25, v3f32, ...).

DataLayout::getTypeAllocSize rounds up based on alignment.
When checking for target intrinsic legality, that's not what we want:
if rounding makes a difference, the type isn't legal, and the
target intrinsics shouldn't be used, as they are always assumed legal.

One could make the argument that alloc size is ultimately the most
relevant here, since we're dealing with LD/ST intrinsics. That's only
true if we did legalize them though; that's a problem for another day.

Use DataLayout::getTypeSizeInBits instead of getTypeAllocSizeInBits.
Type::getSizeInBits can't be used because that'd gratuitously break
pointer vector support.

Some of these uses are currently fine, because we only hit them when
the type is already known legal (e.g., r114454). Update them for
consistency. It's faster to avoid the rounding anyway!

llvm-svn: 255089
2015-12-09 01:19:50 +00:00
Pirama Arumuga Nainar e6ccd7b66a Define selection for v4f16, v8f16 scalar_to_vector
Summary:
This fixes failure when trying to select
    insertelement <4 x half> undef, half %a, i64 0
which gets transformed to a scalar_to_vector node.

The accompanying v4 and v8 tests fail instruction selection without this
patch.

Reviewers: ab, jmolloy

Subscribers: srhines, llvm-commits

Differential Revision: http://reviews.llvm.org/D15322

llvm-svn: 255072
2015-12-08 23:07:06 +00:00
Manman Ren cb8470b4b5 [CXX TLS calling convention] Add support for AArch64.
rdar://9001553

llvm-svn: 254978
2015-12-08 00:14:38 +00:00
Chad Rosier f3491496dc [AArch64] Expand vector SDIVREM/UDIVREM operations.
http://reviews.llvm.org/D15214
Patch by Ana Pazos <apazos@codeaurora.org>!

llvm-svn: 254773
2015-12-04 21:38:44 +00:00
Matthias Braun 0d4505c067 AArch64FastISel: Use cbz/cbnz to branch on i1
In the case of a conditional branch without a preceding cmp we used to emit
a "and; cmp; b.eq/b.ne" sequence, use tbz/tbnz instead.

Differential Revision: http://reviews.llvm.org/D15122

llvm-svn: 254621
2015-12-03 17:19:58 +00:00
Tim Northover f520eff782 AArch64: use ldxp/stxp pair to implement 128-bit atomic loads.
The ARM ARM is clear that 128-bit loads are only guaranteed to have been atomic
if there has been a corresponding successful stxp. It's less clear for AArch32, so
I'm leaving that alone for now.

llvm-svn: 254524
2015-12-02 18:12:57 +00:00
Christof Douma 8b5dc2c94e [AArch64]: Add support for Cortex-A35
Adds support for the new Cortex-A35 ARMv8-A core.

llvm-svn: 254503
2015-12-02 11:53:44 +00:00
Tim Northover f3be9d5c0b AArch64: fix 128-bit shifts
We mustn't introduce a shift of exactly 64-bits for any inputs, since that's an
UNDEF value (and worse, it's not what you want with the natural Arch64
implementation).

The generated code is pretty horrific, but I couldn't come up with an obviously
better alternative (if the amount is constant EXTR could help). Turns out
128-bit shifts are just nasty.

rdar://22491037

llvm-svn: 254475
2015-12-02 00:33:54 +00:00
Weiming Zhao 56ab51870c [AArch64] Fix a corner case in BitFeild select
Summary:
When not useful bits, BitWidth becomes 0 and APInt will not be happy.

See https://llvm.org/bugs/show_bug.cgi?id=25571

We can just mark the operand as IMPLICIT_DEF is none bits of it is used.

Reviewers: t.p.northover, jmolloy

Subscribers: gberry, jmolloy, mgrang, aemerson, llvm-commits, rengolin

Differential Revision: http://reviews.llvm.org/D14803

llvm-svn: 254440
2015-12-01 19:17:49 +00:00
Geoff Berry 5256fcada0 [CodeGenPrepare] Create more extloads and fewer ands
Summary:
Add and instructions immediately after loads that only have their low
bits used, assuming that the (and (load x) c) will be matched as a
extload and the ands/truncs fed by the extload will be removed by isel.

Reviewers: mcrosier, qcolombet, ab

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D14584

llvm-svn: 253722
2015-11-20 22:34:39 +00:00
Arnaud A. de Grandmaison 4e89e9f846 [ShrinkWrap] Teach ShrinkWrap to handle targets requiring a register scavenger.
The included test only checks for a compiler crash for now. Several people are
facing this issue, so we first resolve the crash, and will increase shrinkwrap's
coverage later in a follow-up patch.

llvm-svn: 253718
2015-11-20 21:54:27 +00:00
Jun Bum Lim 80ec0d3f5a [AArch64]Merge narrow zero stores to a wider store
This change merges adjacent zero stores into a wider single store.
For example :
  strh wzr, [x0]
  strh wzr, [x0, #2]
becomes
  str wzr, [x0]

This will fix PR25410.

llvm-svn: 253711
2015-11-20 21:14:07 +00:00
Jun Bum Lim 4c35ccac91 [AArch64]Extend merging narrow loads into a wider load
This change extends r251438 to handle more narrow load promotions
including byte type, unscaled, and signed. For example, this change will
convert :
  ldursh w1, [x0, #-2]
  ldurh  w2, [x0, #-4]
into
  ldur  w2, [x0, #-4]
  asr   w1, w2, #16
  and   w2, w2, #0xffff

llvm-svn: 253577
2015-11-19 17:21:41 +00:00
Pete Cooper 67cf9a723b Revert "Change memcpy/memset/memmove to have dest and source alignments."
This reverts commit r253511.

This likely broke the bots in
http://lab.llvm.org:8011/builders/clang-ppc64-elf-linux2/builds/20202
http://bb.pgr.jp/builders/clang-3stage-i686-linux/builds/3787

llvm-svn: 253543
2015-11-19 05:56:52 +00:00
Quentin Colombet f6645cce91 [AArch64] Enable shrink-wrapping by default.
Differential Revision: http://reviews.llvm.org/D14360

rdar://problem/20820748

llvm-svn: 253520
2015-11-18 23:12:20 +00:00
Pete Cooper 72bc23ef02 Change memcpy/memset/memmove to have dest and source alignments.
Note, this was reviewed (and more details are in) http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html

These intrinsics currently have an explicit alignment argument which is
required to be a constant integer.  It represents the alignment of the
source and dest, and so must be the minimum of those.

This change allows source and dest to each have their own alignments
by using the alignment attribute on their arguments.  The alignment
argument itself is removed.

There are a few places in the code for which the code needs to be
checked by an expert as to whether using only src/dest alignment is
safe.  For those places, they currently take the minimum of src/dest
alignments which matches the current behaviour.

For example, code which used to read:
  call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %src, i32 500, i32 8, i1 false)
will now read:
  call void @llvm.memcpy.p0i8.p0i8.i32(i8* align 8 %dest, i8* align 8 %src, i32 500, i1 false)

For out of tree owners, I was able to strip alignment from calls using sed by replacing:
  (call.*llvm\.memset.*)i32\ [0-9]*\,\ i1 false\)
with:
  $1i1 false)

and similarly for memmove and memcpy.

I then added back in alignment to test cases which needed it.

A similar commit will be made to clang which actually has many differences in alignment as now
IRBuilder can generate different source/dest alignments on calls.

In IRBuilder itself, a new argument was added.  Instead of calling:
  CreateMemCpy(Dst, Src, getInt64(Size), DstAlign, /* isVolatile */ false)
you now call
  CreateMemCpy(Dst, Src, getInt64(Size), DstAlign, SrcAlign, /* isVolatile */ false)

There is a temporary class (IntegerAlignment) which takes the source alignment and rejects
implicit conversion from bool.  This is to prevent isVolatile here from passing its default
parameter to the source alignment.

Note, changes in future can now be made to codegen.  I didn't change anything here, but this
change should enable better memcpy code sequences.

Reviewed by Hal Finkel.

llvm-svn: 253511
2015-11-18 22:17:24 +00:00
Rafael Espindola 449711cb36 Stop producing .data.rel sections.
If a section is rw, it is irrelevant if the dynamic linker will write to
it or not.

It looks like llvm implemented this because gcc was doing it. It looks
like gcc implemented this in the hope that it would put all the
relocated items close together and speed up the dynamic linker.

There are two problem with this:
* It doesn't work. Both bfd and gold will map .data.rel to .data and
  concatenate the input sections in the order they are seen.
* If we want a feature like that, it can be implemented directly in the
  linker since it knowns where the dynamic relocations are.

llvm-svn: 253436
2015-11-18 06:02:15 +00:00
Ahmed Bougacha 88ddeae8bd [AArch64] Promote f16 SELECT_CC CC operands when op is legal.
SELECT_CC has the nasty property of having operands with unrelated
types. So if you do something like:

  f32 = select_cc f16, f16, f32, f32, cc

You'd only look for the action for <select_cc, f32>, but never f16.
If the types are all legal, but the op isn't (as for f16 on AArch64,
or for f128 on x86_64/AArch64?), then you get into trouble.
For f128, we have softenSetCCOperands to handle this case.

Similarly, for f16, we can directly promote the CC operands.

llvm-svn: 253344
2015-11-17 16:45:40 +00:00
Rafael Espindola 65e4902156 Drop prelink support.
The way prelink used to work was

* The compiler decides if a given section only has relocations that
are know to point to the same DSO. If so, it names it
.data.rel.ro.local<something>.
* The static linker puts all of these together.
* The prelinker program assigns addresses to each library and resolves
the local relocations.

There are many problems with this:
* It is incompatible with address space randomization.
* The information passed by the compiler is redundant. The linker
knows if a given relocation is in the same DSO or not. If could sort
by that if so desired.
* There are newer ways of speeding up DSO (gnu hash for example).
* Even if we want to implement this again in the compiler, the previous
  implementation is pretty broken. It talks about relocations that are
  "resolved by the static linker". If they are resolved, there are none
  left for the prelinker. What one needs to track is if an expression
  will require only dynamic relocations that point to the same DSO.

At this point it looks like the prelinker is an historical curiosity.
For example, fedora has retired it because it failed to build for two
releases
(http://pkgs.fedoraproject.org/cgit/prelink.git/commit/?id=eb43100a8331d91c801ee3dcdb0a0bb9babfdc1f)

This patch removes support for it. That is, it stops printing the
".local" sections.

llvm-svn: 253280
2015-11-17 00:51:23 +00:00
James Molloy 67ca6edbb1 [AArch64] Check the expansion of BITREVERSE in regression test
Something I missed from Hal's review, rightly pointed out by Ben Kramer - we should make sure the expansion is properly checked as it can be easy for bugs to creep in.

I've checked the scalar i8 expansion here and the vector i8 expansion in a previous commit.

llvm-svn: 253024
2015-11-13 10:05:31 +00:00
James Molloy bb1dbf530a [SDAG] Fix expansion of BITREVERSE
Richard Trieu noted that UBSan detected an overflowing shift, and the obvious fix caused a crash.

What was happening was that the shiftee (1U) was indeed too small for the possible range of shifts it had to handle, but also we were using "VT.getSizeInBits()" to get the maximum type bitwidth, but we wanted "VT.getScalarSizeInBits()" to get the vector lane size instead of the entire vector size.

Use an APInt for the shift and VT.getScalarSizeInBits().

llvm-svn: 253023
2015-11-13 10:02:36 +00:00
James Molloy 90111f79f9 [SDAG] Introduce a new BITREVERSE node along with a corresponding LLVM intrinsic
Several backends have instructions to reverse the order of bits in an integer. Conceptually matching such patterns is similar to @llvm.bswap, and it was mentioned in http://reviews.llvm.org/D14234 that it would be best if these patterns were matched in InstCombine instead of reimplemented in every different target.

This patch introduces an intrinsic @llvm.bitreverse.i* that operates similarly to @llvm.bswap. For plumbing purposes there is also a new ISD node ISD::BITREVERSE, with simple expansion and promotion support.

The intention is that InstCombine's BSWAP detection logic will be extended to support BITREVERSE too, and @llvm.bitreverse intrinsics emitted (if the backend supports lowering it efficiently).

llvm-svn: 252878
2015-11-12 12:29:09 +00:00
Geoff Berry 2ddfc5e60f [DAGCombiner] Improve zextload optimization.
Summary:
Don't fold
  (zext (and (load x), cst)) -> (and (zextload x), (zext cst))
if
  (and (load x) cst)
will match as a zextload already and has additional users.

For example, the following IR:

  %load = load i32, i32* %ptr, align 8
  %load16 = and i32 %load, 65535
  %load64 = zext i32 %load16 to i64
  store i32 %load16, i32* %dst1, align 4
  store i64 %load64, i64* %dst2, align 8

used to produce the following aarch64 code:

	ldr		w8, [x0]
	and	w9, w8, #0xffff
	and	x8, x8, #0xffff
	str		w9, [x1]
	str		x8, [x2]

but with this change produces the following aarch64 code:

	ldrh		w8, [x0]
	str		w8, [x1]
	str		x8, [x2]

Reviewers: resistor, mcrosier

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D14340

llvm-svn: 252789
2015-11-11 19:42:52 +00:00
Oliver Stannard 21aa762226 Update test to use explicit triple
This is needed for targets which do not support big-endian with the default
triple.

llvm-svn: 252603
2015-11-10 14:09:08 +00:00
Oliver Stannard d414c99b9c [AArch64] Fix halfword load merging for big-endian targets
For big-endian targets, when we merge two halfword loads into a word load, the
order of the halfwords in the loaded value is reversed compared to
little-endian, so the load-store optimiser needs to swap the destination
registers.

This does not affect merging of two word loads, as we use ldp, which treats the
memory as two separate 32-bit words.

llvm-svn: 252597
2015-11-10 11:04:18 +00:00
Tim Northover 339c83e27f AArch64: add experimental support for address tagging.
AArch64 has the ability to use the top 8-bits of an "address" for extra
information, with the memory subsystem automatically masking them off for loads
and stores. When that's happening, we can sometimes skip masks on memory
operations in the compiler.

However, this requires the host OS and support stack to preserve those bits so
it can't be enabled everywhere. In principle iOS 8.0 and above do take the
required precautions and but we'll put it under a flag for now.

llvm-svn: 252573
2015-11-10 00:44:23 +00:00
Charlie Turner 90dafb1b6d [AArch64] Add UABDL patterns for log2 shuffle.
Summary:
This matches the sum-of-absdiff patterns emitted by the vectoriser using log2 shuffles.

Relies on D14207 to be able to match the `extract_subvector(..., 0)`

Reviewers: t.p.northover, jmolloy

Subscribers: aemerson, llvm-commits, rengolin

Differential Revision: http://reviews.llvm.org/D14208

llvm-svn: 252465
2015-11-09 13:10:52 +00:00
Ahmed Bougacha cf49b523a0 [AArch64][FastISel] Don't even try to select vector icmps.
We used to try to constant-fold them to i32 immediates.
Given that fast-isel doesn't otherwise support vNi1, when selecting
the result users, we'd fallback to SDAG anyway.
However, if the users were in another block, we'd insert broken
cross-class copies (GPR32 to FPR64).

Give up, let SDAG agree with itself on a vNi1 legalization strategy.

llvm-svn: 252364
2015-11-06 23:16:53 +00:00
Jun Bum Lim 22fe15ee86 [AArch64]Enable the narrow ld promotion only on profitable microarchitectures
The benefit from converting narrow loads into a wider load (r251438) could be
micro-architecturally dependent, as it assumes that a single load with two bitfield
extracts is cheaper than two narrow loads. Currently, this conversion is
enabled only in cortex-a57 on which performance benefits were verified.

llvm-svn: 252316
2015-11-06 16:27:47 +00:00
Peter Collingbourne d4bff30370 DI: Reverse direction of subprogram -> function edge.
Previously, subprograms contained a metadata reference to the function they
described. Because most clients need to get or set a subprogram for a given
function rather than the other way around, this created unneeded inefficiency.

For example, many passes needed to call the function llvm::makeSubprogramMap()
to build a mapping from functions to subprograms, and the IR linker needed to
fix up function references in a way that caused quadratic complexity in the IR
linking phase of LTO.

This change reverses the direction of the edge by storing the subprogram as
function-level metadata and removing DISubprogram's function field.

Since this is an IR change, a bitcode upgrade has been provided.

Fixes PR23367. An upgrade script for textual IR for out-of-tree clients is
attached to the PR.

Differential Revision: http://reviews.llvm.org/D14265

llvm-svn: 252219
2015-11-05 22:03:56 +00:00
Jun Bum Lim c9879ecfbc [AArch64]Merge halfword loads into a 32-bit load
This recommits r250719, which caused a failure in SPEC2000.gcc
because of the incorrect insert point for the new wider load.

Convert two halfword loads into a single 32-bit word load with bitfield extract
instructions. For example :
  ldrh w0, [x2]
  ldrh w1, [x2, #2]
becomes
  ldr w0, [x2]
  ubfx w1, w0, #16, #16
  and  w0, w0, #ffff

llvm-svn: 251438
2015-10-27 19:16:03 +00:00
Charlie Turner 458e79b814 [ARM] Expand ROTL and ROTR of vector value types
Summary: After D13851 landed, we saw backend crashes when compiling the reduced test case included in this patch. The right fix seems to be to allow these vector types for expansion in instruction selection.

Reviewers: rengolin, t.p.northover

Subscribers: RKSimon, t.p.northover, aemerson, llvm-commits, rengolin

Differential Revision: http://reviews.llvm.org/D14082

llvm-svn: 251401
2015-10-27 10:25:20 +00:00
James Molloy 5b18b4ce96 Revert "[AArch64]Merge halfword loads into a 32-bit load"
This reverts commit r250719. This introduced a codegen fault in SPEC2000.gcc, when compiled for Cortex-A53.

llvm-svn: 251108
2015-10-23 10:41:38 +00:00
Jun Bum Lim d3548303ec [AArch64]Merge halfword loads into a 32-bit load
Convert two halfword loads into a single 32-bit word load with bitfield extract
instructions. For example :
  ldrh w0, [x2]
  ldrh w1, [x2, #2]
becomes
  ldr w0, [x2]
  ubfx w1, w0, #16, #16
  and  w0, w0, #ffff

llvm-svn: 250719
2015-10-19 18:34:53 +00:00
Charlie Turner 434d4599d4 [AArch64] Implement vector splitting on UADDV.
Summary: Fixes PR25056.

Reviewers: mcrosier, junbuml, jmolloy

Subscribers: aemerson, rengolin, llvm-commits

Differential Revision: http://reviews.llvm.org/D13466

llvm-svn: 250520
2015-10-16 15:38:25 +00:00
Matt Arsenault 61dc235f20 DAGCombiner: Combine extract_vector_elt from build_vector
This basic combine was surprisingly missing.
AMDGPU legalizes many operations in terms of 32-bit vector components,
so not doing this results in many extra copies and subregister extracts
that need to be cleaned up later.

InstCombine already does this for the hasOneUse case. The target hook
is to fix a handful of tests which break (e.g. ARM/vmov.ll) which turn
from a vector materialize repeated immediate instruction to a constant
vector load with more scalar copies from it.

llvm-svn: 250129
2015-10-12 23:59:50 +00:00
Jun Bum Lim 54f3ddfbe2 [AArch64]Fix bug in function names in test case
Functions in this test case need to be renamed as its names are the same
as the instructions we are comparing with.

llvm-svn: 250052
2015-10-12 15:34:52 +00:00
Jun Bum Lim 0aace13d18 Improve ISel across lane float min/max reduction
In vectorized float min/max reduction code, the final "reduce" step
is sub-optimal. In AArch64, this change wll combine :

  svn0 = vector_shuffle t0, undef<2,3,u,u>
  fmin = fminnum t0,svn0
  svn1 = vector_shuffle fmin, undef<1,u,u,u>
  cc = setcc fmin, svn1, ole
  n0 = extract_vector_elt cc, #0
  n1 = extract_vector_elt fmin, #0
  n2 = extract_vector_elt fmin, #1
  result = select n0, n1,n2
into :
  result = llvm.aarch64.neon.fminnmv t0

This change extends r247575.

llvm-svn: 249834
2015-10-09 14:11:25 +00:00
Chad Rosier 7c6ac2b8f9 [AArch64] Fold a floating-point divide by power of two into fp conversion.
Part of http://reviews.llvm.org/D13442

llvm-svn: 249579
2015-10-07 17:51:37 +00:00
Chad Rosier fa30c9b436 [AArch64] Fold a floating-point multiply by power of two into fp conversion.
Part of http://reviews.llvm.org/D13442

llvm-svn: 249576
2015-10-07 17:39:18 +00:00
Jeroen Ketema aebca09543 [ARM][AArch64] Only lower to interleaved load/store if the target has NEON
Without an additional check for NEON, the compiler crashes during
legalization of NEON ldN/stN.

Differential Revision: http://reviews.llvm.org/D13508

llvm-svn: 249550
2015-10-07 14:53:29 +00:00
Chad Rosier 4c5a4646bf [AArch64] Remove an unnecessary run line and other cleanup. NFC.
Unscaled load/store combining has been enabled since the initial ARM64 port.  No
need for a redundance run.  Also, add CHECK-LABEL directives.

llvm-svn: 248945
2015-09-30 21:10:02 +00:00
Chad Rosier 11c825f7db [AArch64] Remove an unnecessary restriction on pre-index instructions.
Previously, the index was constrained to the size of the memory operation for
no apparent reason.  This change removes that constraint so that we can form
pre-index instructions with any valid offset.

llvm-svn: 248931
2015-09-30 19:44:40 +00:00
Chad Rosier 1769d8505f Fix test from r248825.
llvm-svn: 248827
2015-09-29 20:50:15 +00:00
Chad Rosier 4315012769 [AArch64] Add support for pre- and post-index LDPSWs.
llvm-svn: 248825
2015-09-29 20:39:55 +00:00
Chad Rosier dabe2534ed [AArch64] Add integer pre- and post-index halfword/byte loads and stores.
llvm-svn: 248817
2015-09-29 18:26:15 +00:00
Cong Hou 15ea016346 Use fixed-point representation for BranchProbability.
BranchProbability now is represented by its numerator and denominator in uint32_t type. This patch changes this representation into a fixed point that is represented by the numerator in uint32_t type and a constant denominator 1<<31. This is quite similar to the representation of BlockMass in BlockFrequencyInfoImpl.h. There are several pros and cons of this change:

Pros:

1. It uses only a half space of the current one.
2. Some operations are much faster like plus, subtraction, comparison, and scaling by an integer.

Cons:

1. Constructing a probability using arbitrary numerator and denominator needs additional calculations.
2. It is a little less precise than before as we use a fixed denominator. For example, 1 - 1/3 may not be exactly identical to 1 / 3 (this will lead to many BranchProbability unit test failures). This should not matter when we only use it for branch probability. If we use it like a rational value for some precise calculations we may need another construct like ValueRatio.

One important reason for this change is that we propose to store branch probabilities instead of edge weights in MachineBasicBlock. We also want clients to use probability instead of weight when adding successors to a MBB. The current BranchProbability has more space which may be a concern.

Differential revision: http://reviews.llvm.org/D12603

llvm-svn: 248633
2015-09-25 23:09:59 +00:00
Sanjay Patel bbbf9a1a34 merge vector stores into wider vector stores and fix AArch64 misaligned access TLI hook (PR21711)
This is a redo of D7208 ( r227242 - http://llvm.org/viewvc/llvm-project?view=revision&revision=227242 ).

The patch was reverted because an AArch64 target could infinite loop after the change in DAGCombiner 
to merge vector stores. That happened because AArch64's allowsMisalignedMemoryAccesses() wasn't telling
the truth. It reported all unaligned memory accesses as fast, but then split some 128-bit unaligned
accesses up in performSTORECombine() because they are slow.

This patch attempts to fix the problem in AArch's allowsMisalignedMemoryAccesses() while preserving
existing (perhaps questionable) lowering behavior.

The x86 test shows that store merging is working as intended for a target with fast 32-byte unaligned
stores.

Differential Revision: http://reviews.llvm.org/D12635
 

llvm-svn: 248622
2015-09-25 21:49:48 +00:00
Chad Rosier 1bbd7fb38e [AArch64] Add support for generating pre- and post-index load/store pairs.
llvm-svn: 248593
2015-09-25 17:48:17 +00:00
Lawrence Hu cac0b89289 Swap loop invariant GEP with loop variant GEP to allow more LICM.
This patch changes the order of GEPs generated by Splitting GEPs
    pass, specially when one of the GEPs has constant and the base is
    loop invariant, then we will generate the GEP with constant first
    when beneficial, to expose more cases for LICM.

    If originally Splitting GEP generate the following:
      do.body.i:
        %idxprom.i = sext i32 %shr.i to i64
        %2 = bitcast %typeD* %s to i8*
        %3 = shl i64 %idxprom.i, 2
        %uglygep = getelementptr i8, i8* %2, i64 %3
        %uglygep7 = getelementptr i8, i8* %uglygep, i64 1032
      ...
    Now it genereates:
      do.body.i:
        %idxprom.i = sext i32 %shr.i to i64
        %2 = bitcast %typeD* %s to i8*
        %3 = shl i64 %idxprom.i, 2
        %uglygep = getelementptr i8, i8* %2, i64 1032
        %uglygep7 = getelementptr i8, i8* %uglygep, i64 %3
      ...

    For no-loop cases, the original way of generating GEPs seems to
    expose more CSE cases, so we don't change the logic for no-loop
    cases, and only limit our change to the specific case we are
    interested in.

llvm-svn: 248420
2015-09-23 19:25:30 +00:00
Ahmed Bougacha 07a844d758 [AArch64] Emit clrex in the expanded cmpxchg fail block.
In the comparison failure block of a cmpxchg expansion, the initial
ldrex/ldxr will not be followed by a matching strex/stxr.
On ARM/AArch64, this unnecessarily ties up the execution monitor,
which might have a negative performance impact on some uarchs.

Instead, release the monitor in the failure block.
The clrex instruction was designed for this: use it.

Also see ARMARM v8-A B2.10.2:
"Exclusive access instructions and Shareable memory locations".

Differential Revision: http://reviews.llvm.org/D13033

llvm-svn: 248291
2015-09-22 17:21:44 +00:00
Stephen Canon 8216d88511 Don't raise inexact when lowering ceil, floor, round, trunc.
The C standard has historically not specified whether or not these functions should raise the inexact flag. Traditionally on Darwin, these functions *did* raise inexact, and the llvm lowerings followed that conventions. n1778 (C bindings for IEEE-754 (2008)) clarifies that these functions should not set inexact. This patch brings the lowerings for arm64 and x86 in line with the newly specified behavior.  This also lets us fold some logic into TD patterns, which is nice.

Differential Revision: http://reviews.llvm.org/D12969

llvm-svn: 248266
2015-09-22 11:43:17 +00:00
Geoff Berry 43ec15e57e [AArch64] Improved bitfield instruction selection.
Summary:
For bitfield insert OR matching, check both operands for larger pattern
first before checking for smaller pattern.

Add pattern for unsigned bitfield insert-in-zero done with SHL+AND.

Resolves PR21631.

Reviewers: jmolloy, t.p.northover

Subscribers: aemerson, rengolin, llvm-commits, mcrosier

Differential Revision: http://reviews.llvm.org/D12908

llvm-svn: 248006
2015-09-18 17:11:53 +00:00
Quentin Colombet b4c6886215 [ShrinkWrap] Refactor the handling of infinite loop in the analysis.
- Strenghten the logic to be sure we hoist the restore point out of the current
  loop. (The fixes a bug with infinite loop, added as part of the patch.)
- Walk over the exit blocks of the current loop to conver to the desired restore
  point in one iteration of the update loop.

llvm-svn: 247958
2015-09-17 23:21:34 +00:00
Jun Bum Lim 34b9bd0435 Improve ISel using across lane min/max reduction
In vectorized integer min/max reduction code, the final "reduce" step
is sub-optimal. In AArch64, this change wll combine :
  %svn0 = vector_shuffle %0, undef<2,3,u,u>
  %smax0 = smax %0, svn0
  %svn3 = vector_shuffle %smax0, undef<1,u,u,u>
  %sc = setcc %smax0, %svn3, gt
  %n0 = extract_vector_elt %sc, #0
  %n1 = extract_vector_elt %smax0, #0
  %n2 = extract_vector_elt $smax0, #1
  %result = select %n0, %n1, n2
becomes :
  %1 = smaxv %0
  %result = extract_vector_elt %1, 0

This change extends r246790.

llvm-svn: 247575
2015-09-14 16:19:52 +00:00
David Blaikie 2f40830dde [opaque pointer type] Add textual IR support for explicit type parameter for global aliases
update.py:
import fileinput
import sys
import re

alias_match_prefix = r"(.*(?:=|:|^)\s*(?:external |)(?:(?:private|internal|linkonce|linkonce_odr|weak|weak_odr|common|appending|extern_weak|available_externally) )?(?:default |hidden |protected )?(?:dllimport |dllexport )?(?:unnamed_addr |)(?:thread_local(?:\([a-z]*\))? )?alias"
plain = re.compile(alias_match_prefix + r" (.*?))(| addrspace\(\d+\) *)\*($| *(?:%|@|null|undef|blockaddress|addrspacecast|\[\[[a-zA-Z]|\{\{).*$)")
cast  = re.compile(alias_match_prefix + r") ((?:bitcast|inttoptr|addrspacecast)\s*\(.* to (.*?)(| addrspace\(\d+\) *)\*\)\s*(?:;.*)?$)")
gep   = re.compile(alias_match_prefix + r") ((?:getelementptr)\s*(?:inbounds)?\s*\((?P<type>.*), (?P=type)(?:\s*addrspace\(\d+\)\s*)?\* .*\)\s*(?:;.*)?$)")

def conv(line):
  m = re.match(cast, line)
  if m:
    return m.group(1) + " " + m.group(3) + ", " + m.group(2)
  m = re.match(gep, line)
  if m:
    return m.group(1) + " " + m.group(3) + ", " + m.group(2)
  m = re.match(plain, line)
  if m:
    return m.group(1) + ", " + m.group(2) + m.group(3) + "*" + m.group(4) + "\n"
  return line

for line in sys.stdin:
  sys.stdout.write(conv(line))

apply.sh:
for name in "$@"
do
  python3 `dirname "$0"`/update.py < "$name" > "$name.tmp" && mv "$name.tmp" "$name"
  rm -f "$name.tmp"
done

The actual commands:
From llvm/src:
find test/ -name *.ll | xargs ./apply.sh
From llvm/src/tools/clang:
find test/ -name *.mm -o -name *.m -o -name *.cpp -o -name *.c | xargs -I '{}' ../../apply.sh "{}"
From llvm/src/tools/polly:
find test/ -name *.ll | xargs ./apply.sh

llvm-svn: 247378
2015-09-11 03:22:04 +00:00
Silviu Baranga df9ce8408a [DAGCombine] Truncate BUILD_VECTOR operators if necessary when constant folding vectors
Summary:
The BUILD_VECTOR node will truncate its operators to match the
type. We need to take this into account when constant folding -
we need to perform a truncation before constant folding the elements.
This is because the upper bits can change the result, depending on
the operation type (for example this is the case for min/max).

This change also adds a regression test.

Reviewers: jmolloy

Subscribers: jmolloy, llvm-commits

Differential Revision: http://reviews.llvm.org/D12697

llvm-svn: 247265
2015-09-10 10:34:34 +00:00
Ahmed Bougacha 05541459fa [AArch64] Match FI+offset in STNP addressing mode.
First, we need to teach isFrameOffsetLegal about STNP.
It already knew about the STP/LDP variants, but those were probably
never exercised, because it's only the load/store optimizer that
generates STP/LDP, and the only user of the method is frame lowering,
which runs earlier.
The STP/LDP cases were wrong: they didn't take into account the fact
that they return two results, not one, so the immediate offset will be
the 4th operand, not the 3rd.

Follow-up to r247234.

llvm-svn: 247236
2015-09-10 01:54:43 +00:00
Ahmed Bougacha c0ac38d584 [AArch64] Match base+offset in STNP addressing mode.
Followup to r247231.

llvm-svn: 247234
2015-09-10 01:48:29 +00:00
Ahmed Bougacha b8886b517d [AArch64] Support selecting STNP.
We could go through the load/store optimizer and match STNP where
we would have matched a nontemporal-annotated STP, but that's not
reliable enough, as an opportunistic optimization.
Insetad, we can guarantee emitting STNP, by matching them at ISel.
Since there are no single-input nontemporal stores, we have to
resort to some high-bits-extracting trickery to generate an STNP
from a plain store.

Also, we need to support another, LDP/STP-specific addressing mode,
base + signed scaled 7-bit immediate offset.
For now, only match the base. Let's make it smart separately.

Part of PR24086.

llvm-svn: 247231
2015-09-10 01:42:28 +00:00
Steven Wu 332eeca1e4 Fix the testcase in r246790
Using generic neon syntax to avoid test failure on apple platforms.

llvm-svn: 246833
2015-09-04 01:39:24 +00:00
Chad Rosier 6c36eff1d6 [AArch64] Improve ISel using across lane addition reduction.
In vectorized add reduction code, the final "reduce" step is sub-optimal.
This change wll combine :

ext  v1.16b, v0.16b, v0.16b, #8
add  v0.4s, v1.4s, v0.4s
dup  v1.4s, v0.s[1]
add  v0.4s, v1.4s, v0.4s

into

addv s0, v0.4s

PR21371
http://reviews.llvm.org/D12325
Patch by Jun Bum Lim <junbuml@codeaurora.org>!

llvm-svn: 246790
2015-09-03 18:13:57 +00:00
Chad Rosier 08ef462d15 Revert "[AArch64] Improve load/store optimizer to handle LDUR + LDR."
This reverts commit r246769.

This appears to have broken Multisource/Benchmarks/tramp3d-v4.

llvm-svn: 246782
2015-09-03 16:41:28 +00:00
Chad Rosier 491a1bd998 [AArch64] Improve load/store optimizer to handle LDUR + LDR.
This patch allows the mixing of scaled and unscaled load/stores to form
load/store pairs.

PR24465
http://reviews.llvm.org/D12116
Many thanks to Ahmed and Michael for fixes and code review.

llvm-svn: 246769
2015-09-03 14:41:37 +00:00
Sanjay Patel 42574203e5 use "unpredictable" metadata in fast-isel when splitting compares
This patch uses the metadata defined in D12341 to avoid creating an unpredictable branch.

Differential Revision: http://reviews.llvm.org/D12342

llvm-svn: 246692
2015-09-02 19:23:23 +00:00
Ahmed Bougacha b0ff6437cb [AArch64] Lower READCYCLECOUNTER using MRS PMCCTNR_EL0.
This matches the ARM behavior. In both cases, the register is part
of the optional Performance Monitors extension, so, add the feature,
and enable it for the A-class processors we support.

Differential Revision: http://reviews.llvm.org/D12425

llvm-svn: 246555
2015-09-01 16:23:45 +00:00
Cong Hou 511298b919 Distribute the weight on the edge from switch to default statement to edges generated in lowering switch.
Currently, when edge weights are assigned to edges that are created when lowering switch statement, the weight on the edge to default statement (let's call it "default weight" here) is not considered. We need to distribute this weight properly. However, without value profiling, we have no idea how to distribute it. In this patch, I applied the heuristic that this weight is evenly distributed to successors.

For example, given a switch statement with cases 1,2,3,5,10,11,20, and every edge from switch to each successor has weight 10. If there is a binary search tree built to test if n < 10, then its two out-edges will have weight 4x10+10/2 = 45 and 3x10 + 10/2 = 35 respectively (currently they are 40 and 30 without considering the default weight). Each distribution (which is 5 here) will be stored in each SwitchWorkListItem for further distribution.

There are some exceptions:

For a jump table header which doesn't have any edge to default statement, we don't distribute the default weight to it.
For a bit test header which covers a contiguous range and hence has no edges to default statement, we don't distribute the default weight to it.
When the branch checks a single value or a contiguous range with no edge to default statement, we don't distribute the default weight to it.
In other cases, the default weight is evenly distributed to successors.

Differential Revision: http://reviews.llvm.org/D12418

llvm-svn: 246522
2015-09-01 01:42:16 +00:00
Hans Wennborg 4a61370b8f Fix CHECK directives that weren't checking.
llvm-svn: 246485
2015-08-31 21:10:35 +00:00
Quentin Colombet a80b9c824e [AArch64][CollectLOH] Remove an invalid assertion and add a test case exposing it.
rdar://problem/22491525

llvm-svn: 246472
2015-08-31 19:02:00 +00:00
Matthias Braun 0acbd08f3c AArch64: Fix loads to lower NEON vector lanes using GPR registers
The ISelLowering code turned insertion turned the element for the
lowest lane of a BUILD_VECTOR into an INSERT_SUBREG, this prohibited
the patterns for SCALAR_TO_VECTOR(Load) to match later. Restrict this
to cases without a load argument.

Reported in rdar://22223823

Differential Revision: http://reviews.llvm.org/D12467

llvm-svn: 246462
2015-08-31 18:25:15 +00:00
Duncan P. N. Exon Smith 814b8e91c7 DI: Require subprogram definitions to be distinct
As a follow-up to r246098, require `DISubprogram` definitions
(`isDefinition: true`) to be 'distinct'.  Specifically, add an assembler
check, a verifier check, and bitcode upgrading logic to combat testcase
bitrot after the `DIBuilder` change.

While working on the testcases, I realized that
test/Linker/subprogram-linkonce-weak-odr.ll isn't relevant anymore.  Its
purpose was to check for a corner case in PR22792 where two subprogram
definitions match exactly and share the same metadata node.  The new
verifier check, requiring that subprogram definitions are 'distinct',
precludes that possibility.

I updated almost all the IR with the following script:

    git grep -l -E -e '= !DISubprogram\(.* isDefinition: true' |
    grep -v test/Bitcode |
    xargs sed -i '' -e 's/= \(!DISubprogram(.*, isDefinition: true\)/= distinct \1/'

Likely some variant of would work for out-of-tree testcases.

llvm-svn: 246327
2015-08-28 20:26:49 +00:00
Quentin Colombet fa4ecb4b9a [AArch64][CollectLOH] Fix a regression that prevented us to detect chains of
more than 2 instructions.

I introduced this regression a while back and did not noticed it because I
somehow forgot to push the initial test cases for the pass!

Fix that as well!

llvm-svn: 246239
2015-08-27 23:47:10 +00:00
Jonathan Roelofs 054026dba2 Fix a case of `CHECK[^:]*$`.
http://reviews.llvm.org/D11917

llvm-svn: 246163
2015-08-27 17:03:14 +00:00
Sanjay Patel 1015661edf fix CHECK-LABEL and wrong label
llvm-svn: 245958
2015-08-25 18:12:40 +00:00
Matthias Braun 25fd09a756 AArch64: Fix testcase of r245640
llvm-svn: 245647
2015-08-21 00:23:19 +00:00
Matthias Braun 46e5639806 AArch64: Fix cmp;ccmp ordering
When producing conditional compare sequences for or operations we need
to negate the operands and the finally tested flags. The thing is if we negate
the finally tested flags this equals a logical negation of all previously
emitted expressions. There was a case missing where we have to order OR
expressions so they get emitted first.

This fixes http://llvm.org/PR24459

llvm-svn: 245641
2015-08-20 23:33:34 +00:00
Matthias Braun 266204b7dc AArch64: Do not create CCMP on multiple users.
Create CMP;CCMP sequences from and/or trees does not gain us anything if
the and/or tree is materialized to a GP register anyway. While most of
the code already checked for hasOneUse() there was one important case
missing.

llvm-svn: 245640
2015-08-20 23:33:31 +00:00
Juergen Ributzka b12248e9cd [AArch64][FastISel] Don't fold shifts with UB.
We are already falling back to SelectionDAG when encountering an shift with UB.
This adds the same checks for shifts with UB that get folded into arithmetic or
logical operations.

This fixes rdar://problem/22345295.

llvm-svn: 245499
2015-08-19 20:52:55 +00:00
Chih-Hung Hsieh fdcf541871 Split ARM and AArch64 emutls.ll test
Differential Revision: http://reviews.llvm.org/D12127

llvm-svn: 245399
2015-08-19 01:44:51 +00:00
Matthias Braun fa3b248a66 DAGCombiner: Improve DAGCombiner select normalization
The current code normalizes select(C0, x, select(C1, x, y)) towards
select(C0|C1, x, y) if the targets prefers that form. This patch adds an
additional rule that if the select(C1, x, y) part already exists in the
function then we want to normalize into the other direction because the
effects of reusing the existing value are bigger than transforming into
the target preferred form.

This addresses regressions following r238793, see also:
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20150727/290272.html

Differential Revision: http://reviews.llvm.org/D11616

llvm-svn: 245350
2015-08-18 20:48:36 +00:00
Matthias Braun 2e920bd04f DAGCombiner: Optimize SELECTs first before turning them into SELECT_CC
This is part of http://reviews.llvm.org/D11616 - I just decided to split
this up into a separate commit.

llvm-svn: 245349
2015-08-18 20:48:29 +00:00
James Molloy ef183397b1 Generate FMINNAN/FMINNUM/FMAXNAN/FMAXNUM from SDAGBuilder.
These only get generated if the target supports them. If one of the variants is not legal and the other is, and it is safe to do so, the other variant will be emitted.

For example on AArch32 (V8), we have scalar fminnm but not fmin.

Fix up a couple of tests while we're here - one now produces better code, and the other was just plain wrong to start with.

llvm-svn: 245196
2015-08-17 07:13:10 +00:00
Simon Pilgrim 0750c84623 [DAGCombiner] Attempt to mask vectors before zero extension instead of after.
For cases where we TRUNCATE and then ZERO_EXTEND to a larger size (often from vector legalization), see if we can mask the source data and then ZERO_EXTEND (instead of after a ANY_EXTEND). This can help avoid having to generate a larger mask, and possibly applying it to several sub-vectors.

(zext (truncate x)) -> (zext (and(x, m))

Includes a minor patch to SystemZ to better recognise 8/16-bit zero extension patterns from RISBG bit-extraction code.

This is the first of a number of minor patches to help improve the conversion of byte masks to clear mask shuffles.

Differential Revision: http://reviews.llvm.org/D11764

llvm-svn: 245160
2015-08-15 13:27:30 +00:00
Ahmed Bougacha cd35787217 [AArch64] Fix FMLS scalar-indexed-from-2s-after-neg patterns.
We canonicalize V64 vectors to V128 through insert_subvector: the other
FMLA/FMLS/FMUL/FMULX patterns match that already, but this one doesn't,
so we'd fail to match fmls and generate fneg+fmla instead.
The vector equivalents are already tested and functional.

llvm-svn: 245107
2015-08-14 22:06:05 +00:00
James Molloy 63be198712 [AArch64] FMINNAN/FMAXNAN on f16 is not legal.
Spotted by Ahmed - in r244594 I inadvertently marked f16 min/max as legal.

I've reverted it here, and marked min/max on scalar f16's as promote. I've also added a testcase. The test just checks that the compiler doesn't fall over - it doesn't create fmin nodes for f16 yet.

llvm-svn: 245035
2015-08-14 09:08:50 +00:00
James Molloy e7695bca0f [AArch64] Small rejig of fmax tests, NFCI.
These tests relied on -enable-no-nans-fp-math, whereas soon they'll take their no-nans hint
from the FCMP instruction itself, so split the no-nans stuff out into its own test.

Also do a slight rejig of instruction order. The old FMIN/MAX backend matching had to deal with looking through casts, which it never did particularly well. Now, instcombine will recognize such patterns and canonicalize the cast outside the select. So modify the test inputs to assume that instcombine has already run.

llvm-svn: 244913
2015-08-13 17:28:10 +00:00
Ahmed Bougacha a196661bb0 [CodeGen] Mark the promoted FCOPYSIGN result FP_ROUND as TRUNCating.
Now that we can properly promote mismatched FCOPYSIGNs (r244858), we
can mark the FP_ROUND on the result as truncating, to expose folding.

FCOPYSIGN doesn't change anything but the sign bit, so
  (fp_round (fcopysign (fpext a), b))
is equivalent to (modulo the sign bit):
  (fp_round (fpext a))
which is a no-op.

llvm-svn: 244862
2015-08-13 01:32:30 +00:00
Ahmed Bougacha b2a9ed910e [AArch64] Cleanup vector-fcopysign.ll test. NFC.
llvm-svn: 244861
2015-08-13 01:20:38 +00:00
Ahmed Bougacha 2a97b1bcf8 [AArch64] Also custom-lowering mismatched vector/f16 FCOPYSIGN.
We can lower them using our cool tricks if we fpext/fptrunc the second
input, like we do for f32/f64.

Follow-up to r243924, r243926, and r244858.

llvm-svn: 244860
2015-08-13 01:13:56 +00:00
Ahmed Bougacha 40ded502ff [CodeGen] When Promoting, don't extend the 2nd FCOPYSIGN operand.
We don't care about its type, and there's even a combine that'll fold
away the FP_EXTEND if we let it run. However, until it does, we'll have
something broken like:
  (f32 (fp_extend (f64 v)))

Scalar f16 follow-up to r243924.

llvm-svn: 244858
2015-08-13 01:09:43 +00:00
John Brawn 75fc09ddba Redo "Make global aliases have symbol size equal to their type"
r242520 was reverted in r244313 as the expected behaviour of the alias
attribute in C is that the alias has the same size as the aliasee. However
we can re-introduce adding the size on the alias when the aliasee does not,
from a source code or object perspective, exist as a discrete entity. This
happens when the aliasee is not a symbol, or when that symbol is private.

Differential Revision: http://reviews.llvm.org/D11943

llvm-svn: 244752
2015-08-12 15:05:39 +00:00
John Brawn 0bef27d836 [GlobalMerge] Only emit aliases for internal linkage variables for non-Mach-O
On Mach-O emitting aliases for the variables that make up a MergedGlobals
variable can cause problems when linking with dead stripping enabled so don't
do that, except for external variables where we must emit an alias.

llvm-svn: 244748
2015-08-12 13:36:48 +00:00
John Brawn 863bfdbfb4 [GlobalMerge] Use private linkage for MergedGlobals variables
Other objects can never reference the MergedGlobals symbol so external linkage
is never needed. Using private instead of internal linkage means the object is
more similar to what it looks like when global merging is not enabled, with
the only difference being that the merged variables are addressed indirectly
relative to the start of the section they are in.

Also add aliases for merged variables with internal linkage, as this also makes
the object be more like what it is when they are not merged.

Differential Revision: http://reviews.llvm.org/D11942

llvm-svn: 244615
2015-08-11 15:48:04 +00:00
Sanjay Patel c454f07eb1 delete FIXME comment; it's fixed
llvm-svn: 244605
2015-08-11 14:35:29 +00:00
Sanjay Patel 74ca312666 fix minsize detection: minsize attribute implies optimizing for size
llvm-svn: 244604
2015-08-11 14:31:14 +00:00
Sanjay Patel 52c2691829 add missing test for machine combiner when optimizing for size
The minsize test will be fixed in the next commit.

llvm-svn: 244603
2015-08-11 14:29:45 +00:00
James Molloy b7b2a1e9b4 [AArch64] Match fminnum/fmaxnum for vector fminnm/fmaxnm instead of an intrinsic.
Lower Intrinsic::aarch64_neon_fmin/fmax to fminnum/fmannum and match that instead. Minimal functional change:

  - Extra tests added because coverage of scalar fminnm/fmaxnm instructions was nonexistant.
  - f16 test updated because now we actually generate scalar fminnm/fmaxnm we no longer need to bail out to a libcall!

llvm-svn: 244595
2015-08-11 12:06:37 +00:00
Alex Lorenz 2f43dd5a12 StackMap: FastISel: Add an appropriate number of immediate operands to the
frame setup instruction.

This commit ensures that the stack map lowering code in FastISel adds an
appropriate number of immediate operands to the frame setup instruction.

The previous code added just one immediate operand, which was fine for a target
like AArch64, but on X86 the ADJCALLSTACKDOWN64 instruction needs two explicit
operands. This caused the machine verifier to report an error when the old code
added just one.

Reviewers: Juergen Ributzka

Differential Revision: http://reviews.llvm.org/D11853

llvm-svn: 244508
2015-08-10 21:27:03 +00:00