This patch implements the following BookII and Book III instructions:
- copy copy_first cp_abort paste paste. paste_last
- msgsync
- slbieg slbsync
- stop
Total 10 instructions
Reviewers: nemanjai hfinkel tjablin amehsan kbarton
llvm-svn: 265504
While preserving the return value for @llvm.experimental.deoptimize at
the IR level is useful during mid-level optimization, doing so at the
machine instruction level requires generating some extra code and a
return that is non-ideal. This change has LLVM lower
```
%val = call @llvm.experimental.deoptimize
ret %val
```
to effectively
```
call @__llvm_deoptimize()
unreachable
```
instead.
llvm-svn: 265502
Don't emit a gc.result for a statepoint lowered from
@llvm.experimental.deoptimize since the call into __llvm_deoptimize is
effectively noreturn. Instead follow the corresponding gc.statepoint
with an "unreachable".
llvm-svn: 265485
Bionic has a defined thread-local location for the stack protector
cookie. Emit a direct load instead of going through __stack_chk_guard.
llvm-svn: 265481
Prior to this patch, CFLAA wouldn't tag arguments/globals properly if
it didn't find any "interesting" edges on them. This means that, if all
you do is store constants to a global or argument, we would never
actually treat it as a global/argument.
Test case:
define void @foo(i32* %A, i32* %B) #0 {
entry:
store i32 0, i32* %A, align 4
store i32 0, i32* %B, align 4
ret void
}
CFLAA would say that %A can't alias %B, because neither pointer was
used in an interesting way. This patch makes us note whether something
is an argument, global, ... regardless of how interesting CFLAA thinks
its uses are.
(For the record, using a value in an interesting way means loading
from it, using it in a GEP, ...)
llvm-svn: 265474
To start with, handle DW_FORM_string names. Follow up commit will handle
the interesting quirk with type units I was originally aiming for here.
llvm-svn: 265452
We only generate LOCKed versions of add/sub when the result is unused.
It often happens that the result is used, but only by a comparison. We
can optimize those out by reusing EFLAGS, which lets us use the proper
instructions, instead of having to fallback to LXADD.
Instead of doing this as an MI peephole (as we do for the other
non-LOCKed (really, non-MR) forms), do it in ISel. It becomes quite
tricky later.
This also makes it eventually possible to stop expanding and/or/xor
if the only user is an icmp (also see D18141).
This uses the LOCK ISD opcodes added by r262244.
Differential Revision: http://reviews.llvm.org/D17633
llvm-svn: 265450
utils/update_test_checks.py was improved with:
http://reviews.llvm.org/rL265414
to CHECK-NEXT the first line of the IR function. This ensures that nothing bad
has happened before that.
llvm-svn: 265417
utils/update_test_checks.py was improved with:
http://reviews.llvm.org/rL265414
to include the first line of the function (expected to be
a comment line). This ensures that nothing bad has happened
before the first actual line of checked asm. It also matches
the existing behavior of the old script.
llvm-svn: 265416
Summary: LanaiSetflagAluCombiner could previously combine instructions across basic building blocks even when not legal. Make the LanaiSetflagAluCombiner more conservative to avoid this.
Reviewers: eliben
Subscribers: joker.eph, llvm-commits
Differential Revision: http://reviews.llvm.org/D18746
llvm-svn: 265411
Presently, CodeGenPrepare deletes all nearly empty (only phi and branch)
basic blocks. This pass can delete loop preheaders which frequently creates
critical edges. A preheader can be a convenient place to spill registers to
the stack. If the entrance to a loop body is a critical edge, then spills
may occur in the loop body rather than immediately before it. This patch
protects loop preheaders from deletion in CodeGenPrepare even if they are
nearly empty.
Since the patch alters the CFG, it affects a large number of test cases.
In most cases, the changes are merely cosmetic (basic blocks have different
names or instruction orders change slightly). I am somewhat concerned about
the test/CodeGen/Mips/brdelayslot.ll test case. If the loop preheader is not
deleted, then the MIPS backend does not take advantage of a branch delay
slot. Consequently, I would like some close review by a MIPS expert.
The patch also partially subsumes D16893 from George Burgess IV. George
correctly notes that CodeGenPrepare does not actually preserve the dominator
tree. I think the dominator tree was usually not valid when CodeGenPrepare
ran, but I am using LoopInfo to mark preheaders, so the dominator tree is
now always valid before CodeGenPrepare.
Author: Tom Jablin (tjablin)
Reviewers: hfinkel george.burgess.iv vkalintiris dsanders kbarton cycheng
http://reviews.llvm.org/D16984
llvm-svn: 265397
This patch adds support for compact jumps similiar to the previous compact
branch support for MIPSR6. Unlike compact branches, compact jumps do not
have a forbidden slot.
As MipsInstrInfo::getEquivalentCompactForm can determine the correct
expansion for jumps and branches for both microMIPS and MIPSR6, remove the
unnecessary distinction in the delay slot filler.
Reviewers: vkalintiris
Subscribers: llvm-commits, dsanders
llvm-svn: 265390
Summary:
I encountered this issue when constant folding during inlining tried to
fold away a bitcast of a double to an x86_mmx, which is not an integral
type. The test case exposes the same issue with a smaller code snippet
during early CSE.
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D18528
llvm-svn: 265367
We missed a handful of .mir tests that existed outside the
test/CodeGen/MIR directory.
Also fix the three powerpc .mir tests that nobody noticed were broken.
llvm-svn: 265350
The original commit miscompiled things on 32-bit Windows, e.g. a Clang
boostrap. It turns out that mergeSPUpdates() was a bit too generous in
what it interpreted as a stack adjustment, causing the following code:
addl $12, %esp
leal -4(%ebp), %esp
To be "optimized" into simply:
addl $8, %esp
This commit tightens up mergeSPUpdates() and includes a new test
(test14 in movtopush.ll) for this situation.
llvm-svn: 265345
Adds some dllexport tests to verify that:
- Variables in bss are exported appropriately
- Non-dllexport symbols aliased to dllexport symbols are not exported
- Symbols declared as dllexport but are not defined are not exported
We plan to enable dllimport/dllexport support for the PS4, and these
additional tests are for points we noticed in our internal testing.
Patch by Warren Ristow!
Differential Revision: http://reviews.llvm.org/D18682
llvm-svn: 265333
Direct callees' that are cast to other function prototypes,
show up in the Call/Invoke instructions as ConstantExpr's.
Currently llvm::CallSite's getCalledFunction() fails
to return the callees in such expressions as direct calls.
Value profiling should avoid instrumenting such cases. Mostly NFC.
llvm-svn: 265330
We can only perform a tail call to a callee that preserves all the
registers that the caller needs to preserve.
This situation happens with calling conventions like preserver_mostcc or
cxx_fast_tls. It was explicitely handled for fast_tls and failing for
preserve_most. This patch generalizes the check to any calling
convention.
Related to rdar://24207743
Differential Revision: http://reviews.llvm.org/D18680
llvm-svn: 265329
Summary:
Useful for debugging since we lose this correlation after the permodule
summary/VST is read and until we later materialize source modules in the
function importer.
Reviewers: joker.eph
Subscribers: llvm-commits, joker.eph
Differential Revision: http://reviews.llvm.org/D18555
llvm-svn: 265327
A seg-fault occurs due to a reference of a null pointer, which is
the value returned by getConstantPart. This function returns
null if the constant part is not found. The code that calls this
function needs to check for the null return value.
Differential Revision: http://reviews.llvm.org/D18718
llvm-svn: 265319
Summary:
This adds the same checks that were added in r264593 to all
target-specific passes that run after register allocation.
Reviewers: qcolombet
Subscribers: jyknight, dsanders, llvm-commits
Differential Revision: http://reviews.llvm.org/D18525
llvm-svn: 265313
time issue. The patch is to solve PR17409 and its duplicates.
analyzeSiblingValues is a N x N complexity algorithm where N is
the number of siblings generated by reg splitting. Although it
causes siginificant compile time issue when N is large, it is also
important for performance since it removes redundent spills and
enables rematerialization.
To solve the compile time issue, the patch removes analyzeSiblingValues
and replaces it with lower cost alternatives containing two parts. The
first part creates a new spill hoisting method in postOptimization of
register allocation. It does spill hoisting at once after all the spills
are generated instead of inside every instance of selectOrSplit. The
second part queries the define expr of the original register for
rematerializaiton and keep it always available during register allocation
even if it is already dead. It deletes those dead instructions only in
postOptimization. With the two parts in the patch, it can remove
analyzeSiblingValues without sacrificing performance.
Differential Revision: http://reviews.llvm.org/D15302
llvm-svn: 265309
Summary:
At this point we should be able to enable IAS by default for O32 without
breaking check-all, or recursion.
Reviewers: vkalintiris
Subscribers: dsanders, llvm-commits
Differential Revision: http://reviews.llvm.org/D18439
llvm-svn: 265302
This adds MC support for fused compare + indirect branch instructions,
ie. CRB, CGRB, CLRB, CLGRB, CIB, CGIB, CLIB, CLGIB. They aren't actually
generated yet -- this is preparation for their use for conditional
returns in the next iteration of D17339.
Author: koriakin
Differential Revision: http://reviews.llvm.org/D18742
llvm-svn: 265296
A cross-thread sequentially consistent fence should be lowered into
z/Architecture's BCR serialization instruction, instead of causing a
fatal error in the back-end.
Author: bryanpkc
Differential Revision: http://reviews.llvm.org/D18644
llvm-svn: 265292
Enable the SystemZ back-end to lower FRAMEADDR and RETURNADDR, which
previously would cause the back-end to crash. Currently, only a
frame count of zero is supported.
Author: bryanpkc
Differential Revision: http://reviews.llvm.org/D18514
llvm-svn: 265291
Implemented truncstore for KNL and skylake-avx512.
Covered vectors from v2i1 to v64i1. We save the value in bits (not in bytes) - v32i1 is saved in 4 bytes.
Differential Revision: http://reviews.llvm.org/D18740
llvm-svn: 265283
Sinking comparisons in CGP can undo the job of hoisting them done
earlier by LICM, and soft-FP makes this an expensive mistake.
A common pattern that produces floating point comparisons uniform
over a loop is an explicit check for division by zero. If the divisor
is hoisted out of the loop, the comparison can also be, but hoisting
the function that unwinds is never legal, since it may cause side
effects in the loop body prior to the unwinding to not be executed.
Differential Revision: http://reviews.llvm.org/D18744
llvm-svn: 265264
Floating point intrinsics in LLVM are generally not speculatively
executed, since most of them are defined to behave the same as libm
functions, which set errno.
However, the only error that can happen when executing ceil, floor,
nearbyint, rint and round libm functions per POSIX.1-2001 is -ERANGE,
and that requires the maximum value of the exponent to be smaller
than the number of mantissa bits, which is not the case with any of
the floating point types supported by LLVM.
The trunc and copysign functions never set errno per per POSIX.1-2001.
Differential Revision: http://reviews.llvm.org/D18643
llvm-svn: 265262
Add support for the AArch64 .cpu directive. This is a slightly involved
directive since the parameter is actually a variable encoded string. The
general structure is:
<cpu>[[+-]<feature>]*
We now map some of the supported string names for features for internal
representation of feature flags. If we encounter one which we do not support,
bail out as we cannot validate the assembly any longer.
Resolves PR27010.
llvm-svn: 265240
Whenever metadata is only referenced by a single function, emit the
metadata just in that function block. This should improve lazy-loading
by reducing the amount of metadata in the global block.
For now, this should catch all DILocations, and anything else that
happens to be referenced only by a single function.
It's also a first step toward a couple of possible future directions
(which this commit does *not* implement):
1. Some debug info metadata is only referenced from compile units and
individual functions. If we can drop the link from the compile
unit, this optimization will get more powerful.
2. Any uniqued metadata that isn't referenced globally can in theory be
emitted in every function block that references it (trading off
bitcode size and full-parse time vs. lazy-load time).
Note: this assumes the new BitcodeReader error checking from r265223.
The metadata stored in function blocks gets purged after parsing each
function, which means unresolved forward references will get lost.
Since all the global metadata should have already been resolved by the
time we get to the function metadata blocks we just need to check for
that case. (If for some reason we need to handle bitcode that fails the
checks in r265223, the fix is to store about-to-be-dropped unresolved
nodes in MetadataList::shrinkTo until they can be handled succesfully by
a future call to MetadataList::tryToResolveCycles.)
llvm-svn: 265226
These function can be dropped by the compiler if they are no longer
referenced in the current module. However there is a change that
another module is still referencing them because of the import.
Multiple solutions can be used:
- Always import LinkOnce when a caller is imported. This ensure that
every module with a call to a LinkOnce has the definition and will
be able to emit it if it emits the call.
- Turn the LinkOnce into Weak, so that it is always emitted.
- Turn all LinkOnce into available_externally and come back after all
modules are codegen'ed to emit only one copy of the linkonce, when
there is still a reference to it.
This patch implement the second option, with am optimization that
only *one* module will turn the LinkOnce into Weak, while the others
will turn it into available_externally, so that there is exactly one
copy emitted for the whole compilation.
http://reviews.llvm.org/D18346
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 265190
A ``swifterror`` attribute can be applied to a function parameter or an
AllocaInst.
This commit does not include any target-specific change. The target-specific
optimization will come as a follow-up patch.
Differential Revision: http://reviews.llvm.org/D18092
llvm-svn: 265189
Was there really no other way to splat a byte in SSE2?
punpcklbw {{.*#+}} xmm0 = xmm0[0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7]
pshuflw {{.*#+}} xmm0 = xmm0[0,0,0,0,4,5,6,7]
pshufd {{.*#+}} xmm0 = xmm0[0,0,1,1]
llvm-svn: 265172
Summary:
Implement BUFFER_ATOMIC_CMPSWAP{,_X2} instructions on all GCN targets, and FLAT_ATOMIC_CMPSWAP{,_X2} on CI+.
32-bit instruction variants tested manually on Kabini and Bonaire. Tests and parts of code provided by Jan Veselý.
Patch by: Vedran Miletić
Reviewers: arsenm, tstellarAMD, nhaehnle
Subscribers: jvesely, scchan, kanarayan, arsenm
Differential Revision: http://reviews.llvm.org/D17280
llvm-svn: 265170
Note however that this is identical to the existing SSE2 run.
What we really want is yet another run for an SSE2 machine that
also has fast unaligned 16-byte accesses.
llvm-svn: 265167
Follow-up to http://reviews.llvm.org/D18566 and http://reviews.llvm.org/D18676 -
where we noticed that an intermediate splat was being generated for memsets of
non-zero chars.
That was because we told getMemsetStores() to use a 32-bit vector element type,
and it happily obliged by producing that constant using an integer multiply.
The 16-byte test that was added in D18566 is now equivalent for AVX1 and AVX2
(no splats, just a vector load), but we have PR27141 to track that splat difference.
Note that the SSE1 path is not changed in this patch. That can be a follow-up.
This patch should resolve PR27100.
llvm-svn: 265161
A catchswitch cannot be preceded by another instruction in the same
basic block (other than a PHI node).
Instead, insert the extract element right after the materialization of
the vectorized value. This isn't optimal but is a reasonable compromise
given the constraints of WinEH.
This fixes PR27163.
llvm-svn: 265157
Follow-up to D18566 - where we noticed that an intermediate splat was being
generated for memsets of non-zero chars.
That was because we told getMemsetStores() to use a 32-bit vector element type,
and it happily obliged by producing that constant using an integer multiply.
The tests that were added in the last patch are now equivalent for AVX1 and AVX2
(no splats, just a vector load), but we have PR27141 to track that splat difference.
In the new tests, the splat via shuffling looks ok to me, but there might be some
room for improvement depending on uarch there.
Note that the SSE1/2 paths are not changed in this patch. That can be a follow-up.
This patch should resolve PR27100.
Differential Revision: http://reviews.llvm.org/D18676
llvm-svn: 265148
Summary: The assembler was picking the wrong JR variant because the pre-R6 one was still enabled at R6.
Author: nitesh.jain
Reviewers: vkalintiris, dsanders
Subscribers: dsanders, llvm-commits, mohit.bhakkad, sagar, bhushan, jaydeep
Differential: D18387
llvm-svn: 265134
Some ARM instructions encode 32-bit immediates as a 8-bit integer (0-255)
and a 4-bit rotation (0-30, even) in its least significant 12 bits. The
original fixup, FK_Data_4, patches the instruction by the value bit-to-bit,
regardless of the encoding. For example, assuming the label L1 and L2 are
0x0 and 0x104 respectively, the following instruction:
add r0, r0, #(L2 - L1) ; expects 0x104, i.e., 260
would be assembled to the following, which adds 1 to r0, instead of 260:
e2800104 add r0, r0, #4, 2 ; equivalently 1
The new fixup kind fixup_arm_mod_imm takes care of the encoding:
e2800f41 add r0, r0, #260
Patch by Ting-Yuan Huang!
llvm-svn: 265122
When a fixup that can be resolved by the assembler is out of range, we should
report an error in the source, rather than crashing.
Differential Revision: http://reviews.llvm.org/D18402
llvm-svn: 265120
Expose LLVMCreateTargetMachineData as data_layout.
As r263530 did for go. From that commit: "LLVMGetTargetDataLayout was
removed from the C API, and then TargetMachine.TargetData was removed.
Later, LLVMCreateTargetMachineData was added to the C API"
Differential Revision: http://reviews.llvm.org/D18677
llvm-svn: 265115
This is intended to be used for ThinLTO incremental build.
Differential Revision: http://reviews.llvm.org/D18213
This is a recommit of r265095 after fixing the Windows issues.
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 265111
This changes some dllexport tests, to verify that some symbols that
should not be exported are not, in a way that improves the robustness
of CHECK-SAME interaction with CHECK-NOT.
We plan to enable dllimport/dllexport support for the PS4, and these
changes are for points we noticed in our internal testing.
Patch by Warren Ristow!
llvm-svn: 265106
This reverts commit r265096, r265095, and r265094.
Windows build is broken, and the validation does not pass.
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 265102
They're not necessary (since the stack pointer is trivially restored on
return), and the way LLVM inserts the stackrestore calls breaks the
IR (we get a stackrestore between the deoptimize call and the return).
llvm-svn: 265101
They're not necessary (since the lifetime of the alloca is trivially
over due to the return), and the way LLVM inserts the lifetime.end
markers breaks the IR (we get a lifetime end marker between the
deoptimize call and the return).
llvm-svn: 265100
Re-enable an assertion enabled by Justin Lebar in rL265092. rL265092
was breaking test/CodeGen/X86/deopt-intrinsic.ll because webkit_jscc
does not like non-i64 return types. Change the test case to not do
that.
llvm-svn: 265099
Previously, HandleLastUse would delete RegRef information for sub-registers
if they were dead even if their corresponding super-register were still live.
If the super-register were later renamed, then the definitions of the
sub-register would not be updated appropriately. This patch alters the
behavior so that RegInfo information for sub-registers is only deleted when
the sub-register and super-register are both dead.
This resolves PR26775. This is the mirror image of Hal's r227311 commit.
Author: Tom Jablin (tjablin)
Reviewers: kbarton uweigand nemanjai hfinkel
http://reviews.llvm.org/D18448
llvm-svn: 265097
This is intended to be used for ThinLTO incremental build.
Differential Revision: http://reviews.llvm.org/D18213
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 265095
Summary:
Previously the NVVMReflect pass would read its configuration from
command-line flags or a static configuration given to the pass at
instantiation time.
This doesn't quite work for clang's use-case. It needs to pass a value
for __CUDA_FTZ down on a per-module basis. We use a module flag for
this, so the NVVMReflect pass needs to be updated to read said flag.
Reviewers: tra, rnk
Subscribers: cfe-commits, jholewinski
Differential Revision: http://reviews.llvm.org/D18672
llvm-svn: 265090
when compiling with LTO.
r244523 a new class DiagnosticInfoOptimizationRemarkAnalysisAliasing for
optimization analysis remarks related to pointer aliasing without
guarding it in isDiagnosticEnabled in LLVMContext.cpp. This caused the
diagnostic message to be printed unconditionally when compiling with
LTO.
This commit cleans up isDiagnosticEnabled and makes sure all the
vectorization optimization remarks are guarded.
rdar://problem/25382153
llvm-svn: 265084
This mostly cosmetic patch moves the DebugEmissionKind enum from DIBuilder
into DICompileUnit. DIBuilder is not the right place for this enum to live
in — a metadata consumer should not have to include DIBuilder.h.
I also added a Verifier check that checks that the emission kind of a
DICompileUnit is actually legal.
http://reviews.llvm.org/D18612
<rdar://problem/25427165>
llvm-svn: 265077
Print aliases in topological order, that is, for any alias a = b,
b must be printed before a. This is because on some targets (e.g. PowerPC)
linker expects aliases in such an order to generate correct TOC information.
GCC also prints aliases in topological order.
llvm-svn: 265064
"blockaddress" can not apply to an external function. All
blockaddress constant uses must belong to the same module as the
definition of the target function.
llvm-svn: 265061
This patch simply mirrors the attributes we give to @llvm.nvvm.reflect
to the __nvvm_reflect libdevice call. This shaves about 30% of the code
in libdevice away because of CSE opportunities. It's also helps us
figure out that libdevice implementations of transcendental functions
don't have side-effects.
llvm-svn: 265060
Summary:
This change will allow loads with imp-def to be clustered in machine-scheduler pass.
areMemAccessesTriviallyDisjoint() can also handle loads with imp-def.
Reviewers: mcrosier, jmolloy, t.p.northover
Subscribers: aemerson, rengolin, mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D18665
llvm-svn: 265051
Chapter 3 of the QPX manual states that, "Scalar floating-point load
instructions, defined in the Power ISA, cause a replication of the source data
across all elements of the target register." Thus, if we have a load followed
by a QPX splat (from the first lane), the splat is redundant. This adds a late
MI-level pass to remove the redundant splats in some of these cases
(specifically when both occur in the same basic block).
This optimization is scheduled just prior to post-RA scheduling. It can't happen
before anything that might replace the load with some already-computed quantity
(i.e. store-to-load forwarding).
llvm-svn: 265047
We don't really support non-constant shuffle masks, but these tests are for cases where BUILD_VECTOR is made up from vector extracts (as well as undef/zero scalars).
llvm-svn: 265045
isBrImm should accept any non-constant immediate. Previously it was only accepting LanaiMCExpr ones which was wrong.
Differential Revision: http://reviews.llvm.org/D18571
llvm-svn: 265032
The test case added in r265023 is failing on ninja-x64-msvc-RA-centos6.
Update the test to make less specific assumptions on code generation.
llvm-svn: 265026
PPCSimplifyAddress contains this code:
IntegerType *OffsetTy = ((VT == MVT::i32) ? Type::getInt32Ty(*Context)
: Type::getInt64Ty(*Context));
to determine the type to be used for an index register, if one needs
to be created. However, the "VT" here is the type of the data being
loaded or stored, *not* the type of an address. This means that if
a data element of type i32 is accessed using an index that does not
not fit into 32 bits, a wrong address is computed here.
Note that PPCFastISel is only ever used on 64-bit currently, so the type
of an address is actually *always* MVT::i64. Other parts of the code,
even in this same PPCSimplifyAddress routine, already rely on that fact.
Thus, this patch changes the code to simply unconditionally use
Type::getInt64Ty(*Context) as OffsetTy.
llvm-svn: 265023
This patch corresponds to review:
http://reviews.llvm.org/D18032
This patch provides asm implementation for the following instructions:
lwat, ldat, stwat, stdat, ldmx, mcrxrx
llvm-svn: 265022
Summary:
This change will handle missing store pair opportunity where the first store
instruction stores zero followed by the non-zero store. For example, this change
will convert :
str wzr, [x8]
str w1, [x8, #4]
into:
stp wzr, w1, [x8]
Reviewers: jmolloy, t.p.northover, mcrosier
Subscribers: flyingforyou, aemerson, rengolin, mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D18570
llvm-svn: 265021
The fast isel pass currently emits a COPY_TO_REGCLASS node to convert
from a F4RC to a F8RC register class during conversion of a
floating-point number to integer. There is actually no support in the
common code instruction printers to emit COPY_TO_REGCLASS nodes, so the
PowerPC back-end has special code there to simply ignore
COPY_TO_REGCLASS.
This is correct *if and only if* the source and destination registers of
COPY_TO_REGCLASS are the same (except for the different register class).
But nothing guarantees this to be the case, and if the register
allocator does end up allocating source and destination to different
registers after all, the back-end simply generates incorrect code. I've
included a test case that shows such incorrect code generation.
However, it seems that COPY_TO_REGCLASS is actually not intended to be
used at the MI layer at all. It is used during SelectionDAG, but always
lowered to a plain COPY before emitting MI. Other back-end's fast isel
passes never emit COPY_TO_REGCLASS at all. I suspect it is simply wrong
for the PowerPC back-end to emit it here.
This patch changes the PowerPC back-end to directly emit COPY instead of
COPY_TO_REGCLASS and removes the special handling in the instruction
printers.
Differential Revision: http://reviews.llvm.org/D18605
llvm-svn: 265020
Summary:
There are too many instructions to exhaustively test so addiu and lwc2 are
used as representative examples.
It should be noted that many memory instructions that should have simm16
range checking do not because it is also necessary to support the macro
of the same name which accepts simm32. The range checks for these occur in
the macro expansion.
Reviewers: vkalintiris
Subscribers: dsanders, llvm-commits
Differential Revision: http://reviews.llvm.org/D18437
llvm-svn: 265019
Summary:
ldc2/sdc2 now emit slightly worse diagnostics for MIPS-I. The problem
is that they don't trigger the custom parser because all the candidates
are disabled by feature bits. On all other subtargets, the diagnostics are
accurate but are subject to the usual issues of needing to report multiple
ways to correct the code (e.g. smaller offset, enable a CPU feature) but
only being able to report one error.
Reviewers: vkalintiris
Subscribers: dsanders, llvm-commits
Differential Revision: http://reviews.llvm.org/D18436
llvm-svn: 265018
Summary:
Also, made test_mi10.s formatting consistent with the majority of the
MC tests.
Reviewers: vkalintiris
Subscribers: dsanders, llvm-commits
Differential Revision: http://reviews.llvm.org/D18435
llvm-svn: 265014
Summary:
The bug was that microMIPS's [ls]w[lr]e instructions claimed to support a
12-bit offset when it is only 9-bit.
Reviewers: vkalintiris
Subscribers: llvm-commits, dsanders
Differential Revision: http://reviews.llvm.org/D18434
llvm-svn: 265010
PPC has a vector popcount, this lets the vectorizer use the correct cost
for it. Tweak X86 test to use an intrinsic that's actually scalarized (we
have a somewhat efficient lowering for vector popcount using SSE, the
cost model finds that now).
llvm-svn: 265005
* LLVMDisposeMessage lives in llvm-c/Core.h, include this file where necessary
* LLVMAddTargetData has been removed, follow suit in the bindings
Differential Revision: http://reviews.llvm.org/D18633
llvm-svn: 265001
When dealing with complex<float>, and similar structures with two
single-precision floating-point numbers, especially when such things are being
passed around by value, we'll sometimes end up loading both float values by
extracting them from one 64-bit integer load. It looks like this:
t13: i64,ch = load<LD8[%ref.tmp]> t0, t6, undef:i64
t16: i64 = srl t13, Constant:i32<32>
t17: i32 = truncate t16
t18: f32 = bitcast t17
t19: i32 = truncate t13
t20: f32 = bitcast t19
The problem, especially before the P8 where those bitcasts aren't legal (and
get expanded via the stack), is that it would have been better to use two
floating-point loads directly. Here we add a target-specific DAGCombine to do
just that. In short, we turn:
ld 3, 0(5)
stw 3, -8(1)
rldicl 3, 3, 32, 32
stw 3, -4(1)
lfs 3, -4(1)
lfs 0, -8(1)
into:
lfs 3, 4(5)
lfs 0, 0(5)
llvm-svn: 264988
The test case was defining and using a function 'notExported()', but
the FileCheck checks were checking for the name 'not_exported'. This
changes the test to use 'notExported' across the board. Also, the test
defined a function 'not_defined()', but doesn't have any checks related
to it. For consistency, this name is changed to 'notDefined'. A later
commit will add checks for 'notDefined'.
Patch by Warren Ristow!
llvm-svn: 264984
Summary:
As discussed on llvm-dev[1].
This change adds the basic boilerplate code around having this intrinsic
in LLVM:
- Changes in Intrinsics.td, and the IR Verifier
- A lowering pass to lower @llvm.experimental.guard to normal
control flow
- Inliner support
[1]: http://lists.llvm.org/pipermail/llvm-dev/2016-February/095523.html
Reviewers: reames, atrick, chandlerc, rnk, JosephTremoulet, echristo
Subscribers: mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D18527
llvm-svn: 264976
The size savings are significant, and from what I can tell, both ICC and GCC do this.
Differential Revision: http://reviews.llvm.org/D18573
llvm-svn: 264966
r264884 introduced a helper to escape the backslashes in the source file
path, but I since discovered an existing mechanism to escape strings.
llvm-svn: 264936
Widening a PHI requires us to insert a trunc.
The logical place for this trunc is in the same BB as the PHI.
This is not possible if the BB is terminated by a catchswitch.
This fixes PR27133.
llvm-svn: 264926
Fix for issue introduced D17297, where we were breaking early from the loop detecting consecutive loads which could leave us thinking a consecutive load with zeros was possible.
llvm-svn: 264922
The TailDup transform was removed in r138841 in 2011, along with most
of the tests for it. This test, however, was missed. Probably because
it had already been XFAIL'd for 3 years at that point (since r52243!)
and continued to fail when the opt flag for -tailduplicate stopped
being valid.
llvm-svn: 264916
This change prevents the loop vectorizer from vectorizing when all of the vector
types it generates will be scalarized. I've run into this problem on the PPC's QPX
vector ISA, which only holds floating-point vector types. The loop vectorizer
will, however, happily vectorize loops with purely integer computation. Here's
an example:
LV: The Smallest and Widest types: 32 / 32 bits.
LV: The Widest register is: 256 bits.
LV: Found an estimated cost of 0 for VF 1 For instruction: %indvars.iv25 = phi i64 [ 0, %entry ], [ %indvars.iv.next26, %for.body ]
LV: Found an estimated cost of 0 for VF 1 For instruction: %arrayidx = getelementptr inbounds [1600 x i32], [1600 x i32]* %a, i64 0, i64 %indvars.iv25
LV: Found an estimated cost of 0 for VF 1 For instruction: %2 = trunc i64 %indvars.iv25 to i32
LV: Found an estimated cost of 1 for VF 1 For instruction: store i32 %2, i32* %arrayidx, align 4
LV: Found an estimated cost of 1 for VF 1 For instruction: %indvars.iv.next26 = add nuw nsw i64 %indvars.iv25, 1
LV: Found an estimated cost of 1 for VF 1 For instruction: %exitcond27 = icmp eq i64 %indvars.iv.next26, 1600
LV: Found an estimated cost of 0 for VF 1 For instruction: br i1 %exitcond27, label %for.cond.cleanup, label %for.body
LV: Scalar loop costs: 3.
LV: Found an estimated cost of 0 for VF 2 For instruction: %indvars.iv25 = phi i64 [ 0, %entry ], [ %indvars.iv.next26, %for.body ]
LV: Found an estimated cost of 0 for VF 2 For instruction: %arrayidx = getelementptr inbounds [1600 x i32], [1600 x i32]* %a, i64 0, i64 %indvars.iv25
LV: Found an estimated cost of 0 for VF 2 For instruction: %2 = trunc i64 %indvars.iv25 to i32
LV: Found an estimated cost of 2 for VF 2 For instruction: store i32 %2, i32* %arrayidx, align 4
LV: Found an estimated cost of 1 for VF 2 For instruction: %indvars.iv.next26 = add nuw nsw i64 %indvars.iv25, 1
LV: Found an estimated cost of 1 for VF 2 For instruction: %exitcond27 = icmp eq i64 %indvars.iv.next26, 1600
LV: Found an estimated cost of 0 for VF 2 For instruction: br i1 %exitcond27, label %for.cond.cleanup, label %for.body
LV: Vector loop of width 2 costs: 2.
LV: Found an estimated cost of 0 for VF 4 For instruction: %indvars.iv25 = phi i64 [ 0, %entry ], [ %indvars.iv.next26, %for.body ]
LV: Found an estimated cost of 0 for VF 4 For instruction: %arrayidx = getelementptr inbounds [1600 x i32], [1600 x i32]* %a, i64 0, i64 %indvars.iv25
LV: Found an estimated cost of 0 for VF 4 For instruction: %2 = trunc i64 %indvars.iv25 to i32
LV: Found an estimated cost of 4 for VF 4 For instruction: store i32 %2, i32* %arrayidx, align 4
LV: Found an estimated cost of 1 for VF 4 For instruction: %indvars.iv.next26 = add nuw nsw i64 %indvars.iv25, 1
LV: Found an estimated cost of 1 for VF 4 For instruction: %exitcond27 = icmp eq i64 %indvars.iv.next26, 1600
LV: Found an estimated cost of 0 for VF 4 For instruction: br i1 %exitcond27, label %for.cond.cleanup, label %for.body
LV: Vector loop of width 4 costs: 1.
...
LV: Selecting VF: 8.
LV: The target has 32 registers
LV(REG): Calculating max register usage:
LV(REG): At #0 Interval # 0
LV(REG): At #1 Interval # 1
LV(REG): At #2 Interval # 2
LV(REG): At #4 Interval # 1
LV(REG): At #5 Interval # 1
LV(REG): VF = 8
The problem is that the cost model here is not wrong, exactly. Since all of
these operations are scalarized, their cost (aside from the uniform ones) are
indeed VF*(scalar cost), just as the model suggests. In fact, the larger the VF
picked, the lower the relative overhead from the loop itself (and the
induction-variable update and check), and so in a sense, picking the largest VF
here is the right thing to do.
The problem is that vectorizing like this, where all of the vectors will be
scalarized in the backend, isn't really vectorizing, but rather interleaving.
By itself, this would be okay, but then the vectorizer itself also interleaves,
and that's where the problem manifests itself. There's aren't actually enough
scalar registers to support the normal interleave factor multiplied by a factor
of VF (8 in this example). In other words, the problem with this is that our
register-pressure heuristic does not account for scalarization.
While we might want to improve our register-pressure heuristic, I don't think
this is the right motivating case for that work. Here we have a more-basic
problem: The job of the vectorizer is to vectorize things (interleaving aside),
and if the IR it generates won't generate any actual vector code, then
something is wrong. Thus, if every type looks like it will be scalarized (i.e.
will be split into VF or more parts), then don't consider that VF.
This is not a problem specific to PPC/QPX, however. The problem comes up under
SSE on x86 too, and as such, this change fixes PR26837 too. I've added Sanjay's
reduced test case from PR26837 to this commit.
Differential Revision: http://reviews.llvm.org/D18537
llvm-svn: 264904
Summary:
This results in higher register usage, but should make it easier for
the compiler to hide latency.
This pass is a prerequisite for some more scheduler improvements, and I
think the increase register usage with this patch is acceptable, because
when combined with the scheduler improvements, the total register usage
will decrease.
shader-db stats:
2382 shaders in 478 tests
Totals:
SGPRS: 48672 -> 49088 (0.85 %)
VGPRS: 34148 -> 34847 (2.05 %)
Code Size: 1285816 -> 1289128 (0.26 %) bytes
LDS: 28 -> 28 (0.00 %) blocks
Scratch: 492544 -> 573440 (16.42 %) bytes per wave
Max Waves: 6856 -> 6846 (-0.15 %)
Wait states: 0 -> 0 (0.00 %)
Depends on D18451
Reviewers: nhaehnle, arsenm
Subscribers: arsenm, llvm-commits
Differential Revision: http://reviews.llvm.org/D18452
llvm-svn: 264876
For compatability with GAS, nop and nopr are recognized as alises for
bc and bcr, respectively. A mask of 0 turns these instructions
effectively into no-operations.
Reviewed by Ulrich Weigand.
llvm-svn: 264875
This reverts commit r264869. I am seeing Windows bot failures due to the
"\" in the path being mishandled at some point (seems to be interpreted
wrongly at some point and llvm-as | llvm-dis is yielding some junk
characters). Need to investigate.
llvm-svn: 264871
XOP's VPPERM has some great 'permute operations' that it can do as well as part of shuffling the bytes of a 128-bit vector - in this case we use it to perform BITREVERSE in a single instruction.
llvm-svn: 264870
Summary:
This change serializes out and in the SourceFileName to LLVM assembly
so that it is preserved through "llvm-dis | llvm-as". This is
necessary to ensure that the global identifiers created for local values
in the module summary index are the same even if the bitcode is
streamed out and read back from LLVM assembly.
Serializing the summary itself to LLVM assembly is in progress.
Reviewers: joker.eph
Subscribers: llvm-commits, joker.eph
Differential Revision: http://reviews.llvm.org/D18588
llvm-svn: 264869
We are currently doing a REALLY bad job of packing results of vector comparisons into the legalized <X x i1> result equivalents - a mixture of PACKSS/PMOVMSKB would be much better here.
llvm-svn: 264867
We already try not to truncate PHIs in computeMinimalBitwidths. LoopVectorize can't handle it and we really don't need to, because both induction and reduction PHIs are truncated by other means.
However, we weren't bailing out in all the places we should have, and we ended up by returning a PHI to be truncated, which has caused PR27018.
This fixes PR17018.
llvm-svn: 264852
operations.
Specifically, we had code that tried to badly approximate reconstructing
all of the possible variations on addressing modes in two x86
instructions based on those in one pseudo instruction. This is not the
first bug uncovered with doing this, so stop doing it altogether.
Instead generically and pedantically copy every operand from the address
over to both new instructions, and strip kill flags from any register
operands.
This fixes a subtle bug seen in the wild where we would mysteriously
drop parts of the addressing mode, causing for example the index
argument in the added test case to just be completely ignored.
Hypothetically, this was an extremely bad miscompile because it actually
caused a predictable and leveragable write of a 64bit quantity to an
unintended offset (the first element of the array intead of whatever
other element was intended). As a consequence, in theory this could even
have introduced security vulnerabilities.
However, this was only something that could happen with an atomic
floating point add. No other operation could trigger this bug, so it
seems extremely unlikely to have occured widely in the wild.
But it did in fact occur, and frequently in scientific applications
which were using relaxed atomic updates of a floating point value after
adding a delta. Those would end up being quite badly miscompiled by
LLVM, which is how we found this. Of course, this often looks like
a race condition in the code, but it was actually a miscompile.
I suspect that this whole RELEASE_FADD thing was a complete mistake.
There is no such operation, and I worry that anything other than add
will get remarkably worse codegeneration. But that's not for this
change....
llvm-svn: 264845
Prior to this patch, the MemorySSA caching visitor would cache all
calls that it visited. When paired with phi optimization, this can be
problematic. Consider:
define void @foo() {
; 1 = MemoryDef(liveOnEntry)
call void @clobberFunction()
br i1 undef, label %if.end, label %if.then
if.then:
; MemoryUse(??)
call void @readOnlyFunction()
; 2 = MemoryDef(1)
call void @clobberFunction()
br label %if.end
if.end:
; 3 = MemoryPhi(...)
; MemoryUse(?)
call void @readOnlyFunction()
ret void
}
When optimizing MemoryUse(?), we visit defs 1 and 2, so we note to
cache them later. We ultimately end up not being able to optimize
passed the Phi, so we set MemoryUse(?) to point to the Phi. We then
cache the clobbering call for def 1 to be the Phi.
This commit changes this behavior so that we wipe out any calls
added to VisistedCalls while visiting the defs of a phi we couldn't
optimize.
Aside: With this patch, we now can bootstrap clang/LLVM without a
single MemorySSA verifier failure. Woohoo. :)
llvm-svn: 264820
This patch teaches the caching MemorySSA walker a few things:
1. Not to walk Phis we've walked before. It seems that we tried to do
this before, but it didn't work so well in cases like:
define void @foo() {
%1 = alloca i8
%2 = alloca i8
br label %begin
begin:
; 3 = MemoryPhi({%0,liveOnEntry},{%end,2})
; 1 = MemoryDef(3)
store i8 0, i8* %2
br label %end
end:
; MemoryUse(?)
load i8, i8* %1
; 2 = MemoryDef(1)
store i8 0, i8* %2
br label %begin
}
Because we wouldn't put Phis in Q.Visited until we tried to visit them.
So, when trying to optimize MemoryUse(?):
- We would visit 3 above
- ...Which would make us put {%0,liveOnEntry} in Q.Visited
- ...Which would make us visit {%0,liveOnEntry}
- ...Which would make us put {%end,2} in Q.Visited
- ...Which would make us visit {%end,2}
- ...Which would make us visit 3
- ...Which would realize we've already visited everything in 3
- ...Which would make us conservatively return 3.
In the added test-case, (@looped_visitedonlyonce) this behavior would
cause us to give incorrect results. Specifically, we'd visit 4 twice
in the same query, but on the second visit, we'd skip while.cond because
it had been visited, visit if.then/if.then2, and cache "1" as the
clobbering def on the way back.
2. If we try to walk the defs of a {Phi,MemLoc} and see it has been
visited before, just hand back the Phi we're trying to optimize.
I promise this isn't as terrible as it seems. :)
We now insert {Phi,MemLoc} pairs just before walking the Phi's upward
defs. So, we check the cache for the {Phi,MemLoc} pair before checking
if we've already walked the Phi.
The {Phi,MemLoc} pair is (almost?) always guaranteed to have a cache
entry if we've already fully walked it, because we cache as we go.
So, if the {Phi,MemLoc} pair isn't in cache, either:
(a) we must be in the process of visiting it (in which case, we can't
give a better answer in a cache-as-we-go DFS walker)
(b) we visited it, but didn't cache it on the way back (...which seems
to require `ModifyingAccess` to not dominate `StartingAccess`,
so I'm 99% sure that would be an error. If it's not an error, I
haven't been able to get it to happen locally, so I suspect it's
rare.)
- - - - -
As a consequence of this change, we no longer skip upward defs of phis,
so we can kill the `VisitedOnlyOne` check. This gives us better accuracy
than we had before, at the cost of potentially doing a bit more work
when we have a loop.
llvm-svn: 264814
This is effectively NFC, minus the renaming of the options
(-cyclone-prefetch-distance -> -prefetch-distance).
The change was requested by Tim in D17943.
llvm-svn: 264806
We have known races on profile counters, which can be reproduced by enabling
-fsanitize=thread and -fprofile-instr-generate simultaneously on a
multi-threaded program. This patch avoids reporting those races by not
instrumenting the reads and writes coming from the instruction profiler.
llvm-svn: 264805
During ADCE, track which debug info scopes still have live references
from the code, and delete debug info intrinsics for the dead ones.
These intrinsics describe the locations of variables (in registers or
stack slots). If there's no code left corresponding to a variable's
scope, then there's no way to reference the variable in the debugger and
it doesn't matter what its value is.
I add a DEBUG printout when the described location in an SSA register,
in case it helps some trying to track down why locations get lost.
However, we still delete these; the scope itself isn't attached to any
real code, so the ship has already sailed.
llvm-svn: 264800
1. Removed the run line for mingw32 and made the Darwin triples unknown.
This is a test of 32-bit vs. 64-bit platform and the underlying hardware.
We have other tests for checking behavioral differences of the OS platform.
2. Changed the CPU specifiers to the attributes they were meant to represent.
Any CPU that doesn't have SSE4.2 is assumed to have slow unaligned 16-byte accesses,
so it won't use those here.
3. Although the stores really could all be CHECK-DAG, I left them as CHECK-NEXT to
show the strange behavior of the instruction scheduler in the SLOW_32 case.
4. The odd-looking instructions are due to the use of a null pointer in the IR, so
we have integer immediate store addresses. Cute.
llvm-svn: 264796
http://pubs.opengroup.org/onlinepubs/9699919799/utilities/nm.html .
1) For Mach-O files the code was not printing the values in hex as is the default.
2) The values printed had leading zeros which they should not have.
3) The address for undefined symbols was printed as spaces instead of 0.
4) With the -A option with posix output for an archive did not use square
brackets around the archive member name.
rdar://25311883 and rdar://25299678
llvm-svn: 264778
Add function soft attribute to the generation of Jump Tables in CodeGen
as initial step towards clang support of gcc's no-jump-table support
Reviewers: hans, echristo
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D18321
llvm-svn: 264756
Fixed fp_to_uint instruction selection on KNL.
One pattern was missing for <4 x double> to <4 x i32>
Differential Revision: http://reviews.llvm.org/D18512
llvm-svn: 264701
When eliminating or merging almost empty basic blocks, the existence of non-trivial PHI nodes
is currently used to recognize potential loops of which the block is the header and keep the block.
However, the current algorithm fails if the loops' exit condition is evaluated only with volatile
values hence no PHI nodes in the header. Especially when such a loop is an outer loop of a nested
loop, the loop is collapsed into a single loop which prevent later optimizations from being
applied (e.g., transforming nested loops into simplified forms and loop vectorization).
The patch augments the existing PHI node-based check by adding a pre-test if the BB actually
belongs to a set of loop headers and not eliminating it if yes.
llvm-svn: 264697
Instead of using two feature bits, one to indicate the availability of the
popcnt[dw] instructions, and another to indicate whether or not they're fast,
use a single enum. This allows more consistent control via target attribute
strings, and via Clang's command line.
llvm-svn: 264690
Minimum density for both optsize and non optsize are now options
-sparse-jump-table-density (default 10) for non optsize functions
-dense-jump-table-density (default 40) for optsize functions, which
matches the current default. This improves several benchmarks at google
at the cost of a small codesize increase. For code compiled with -Os,
the old behavior continues
llvm-svn: 264689
Personality is copied as part of copyFunctionAttributes, but it is
invalid on a declaration. Remove the personality attribute it the
function body is not cloned.
Also add a verifier run over output modules in the llvm-split tool.
llvm-svn: 264667
If all a BUILD_VECTOR's source elements are the same bit (AND/XOR/OR) operation type and each has one constant operand, lower to a pair of BUILD_VECTOR and just apply the bit operation to the vectors.
The constant operands will form a constant vector meaning that we still only have a single BUILD_VECTOR to lower and we will have replaced all the scalarized operations with a single SSE equivalent.
Its not in our interest to start make a general purpose vectorizer from this, but I'm seeing enough of these scalar bit operations from the later legalization/scalarization stages to support them at least.
Differential Revision: http://reviews.llvm.org/D18492
llvm-svn: 264666
Function names in ObjC can have spaces in them. This interacts poorly
with name compression, which uses spaces to separate PGO names. Fix the
issue by using a different separator and update a test.
I chose "\01" as the separator because 1) it's non-printable, 2) we
strip it from PGO names, and 3) it's the next natural choice once "\00"
is discarded (that one's overloaded).
What's changed since the original commit?
- I fixed up the covmap-V2 binary format tests using a linux VM.
- I weakened the CHECK lines in instrprof-comdat.h to account for the
fact that there have been bugfixes to clang coverage. These will be
fixed up in a follow-up.
- I added an assert to make sure we don't get bitten by this again.
- I constructed the c-general.profraw file without name compression
enabled to appease some bots.
Differential Revision: http://reviews.llvm.org/D18516
llvm-svn: 264658
A DICompileUnit that is not listed in llvm.dbg.cu will cause assertion
failures and/or crashes in the backend. The Verifier should reject this.
rdar://problem/25369499
llvm-svn: 264657
This is a fix for PR26941.
When there is both a section and a global definition with the same
name, the global wins.
Section symbols are not added to the symbol table; section references
are left undefined and fixed up in the object writer unless they've
been satisfied by some other definition.
llvm-svn: 264649
On OS X El Capitan and iOS 9, the linker supports a new section
attribute, live_support, which allows dead stripping to remove dead
globals along with the ASAN metadata about them.
With this change __asan_global structures are emitted in a new
__DATA,__asan_globals section on Darwin.
Additionally, there is a __DATA,__asan_liveness section with the
live_support attribute. Each entry in this section is simply a tuple
that binds together the liveness of a global variable and its ASAN
metadata structure. Thus the metadata structure will be alive if and
only if the global it references is also alive.
Review: http://reviews.llvm.org/D16737
llvm-svn: 264645
Function names in ObjC can have spaces in them. This interacts poorly
with name compression, which uses spaces to separate PGO names. Fix the
issue by using a different separator and update a test.
I chose "\01" as the separator because 1) it's non-printable, 2) we
strip it from PGO names, and 3) it's the next natural choice once "\00"
is discarded (that one's overloaded).
This reverts the revert commit beaf3d18. What's changed?
- I fixed up the covmap-V2 binary format tests using a linux VM.
- I updated the expected counts in instrprof-comdat.h to account for
the fact that there have been bugfixes to clang coverage.
- I added an assert to make sure we don't get bitten by this again.
Differential Revision: http://reviews.llvm.org/D18516
llvm-svn: 264641
They do have a def machine operand.
Fixing the definition is necessary for an upcoming patch.
Differential Revision: http://reviews.llvm.org/D18384
llvm-svn: 264607