Commit Graph

115425 Commits

Author SHA1 Message Date
Sanjay Patel
62dd074fe9 use update_llc_test_checks.py to tighten checking in these tests
1. There were no CHECK-LABELs, so we could match instructions from the wrong function.
2. The use of zero operands meant multiple xor instructions could match some CHECKs.
3. The test was over-specified to need a Sandybridge CPU and Darwin triple.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233198 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-25 17:34:11 +00:00
Benjamin Kramer
2ebb9f08ab llvm-jitlistener: Add missing include.
This code is only compiled when LLVM_USE_INTEL_JITEVENTS, but at least we have
one buildbot where that's the case :)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233197 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-25 17:12:36 +00:00
Benjamin Kramer
eaf3cbd897 [APInt] Add an isSplat helper and use it in some places.
To complement getSplat. This is more general than the binary
decomposition method as it also handles non-pow2 splat sizes.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233195 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-25 16:49:59 +00:00
Benjamin Kramer
17a29a4847 [Hexagon] Pattern match a CTZ loop into a call to countTrailingZeros.
No functional change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233192 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-25 15:36:57 +00:00
Benjamin Kramer
4d09974cf3 [ARM] Rewrite .save/.vsave emission with bit math
Hopefully makes it a bit easier to understand what's going on.
No functional change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233191 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-25 15:27:58 +00:00
Daniel Jasper
a427f12c6d Make exit-code test use same mechanism as existing one.
The other version doesn't properly work with our internal test runner,
which sets pipefail.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233188 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-25 14:35:40 +00:00
Rafael Espindola
d033c4b576 Fix fixup evaluation when deciding what to relocate with.
The previous logic was to first try without relocations at all
and failing that stop on the first defined symbol.

That was inefficient and incorrect in the case part of the
expression could be simplified and another part could not
(see included test).

We now stop the evaluation when we get to a variable whose value
can change (i.e. is weak).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233187 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-25 13:16:53 +00:00
Lang Hames
34676181c9 [Orc] Remove another unnecessary typedef.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233184 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-25 12:32:36 +00:00
Andrea Di Biagio
962dcdfdda [optnone] Skip pass Float2Int on optnone functions.
Added test Float2Int/float2int-optnone.ll to verify that pass Float2Int
is not run on optnone functions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233183 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-25 12:22:37 +00:00
Lang Hames
47fd5639bc [Orc][lli] Add a very simple Orc-based lazy JIT to lli.
This ensures that we're building and testing the CompileOnDemand layer, at least
in a basic way.

Currently x86-64 only, and with limited to no library calls enabled (depending
on host platform). Patches welcome. ;)

To enable access to the lazy JIT, this patch replaces the '-use-orcmcjit' lli
option with a new option:
'-jit-kind={ mcjit | orc-mcjit | orc-lazy }'.

All regression tests are updated to use the new option, and one trivial test of
the new lazy JIT is added.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233182 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-25 12:11:48 +00:00
Andrea Di Biagio
3132115738 [X86] Simplify check lines in tests. No functional change.
Also, removed unused check lines from test atomic6432.ll.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233181 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-25 11:44:19 +00:00
James Molloy
09f1b672cb Reapply r233062: "float2int": Add a new pass to demote from float to int where possible.
Now with a fix for PR23008 and extra regression test.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233175 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-25 10:03:42 +00:00
Justin Bogner
c0ffe0f061 test: Fix the dependencies for the check-llvm-* targets
In r233009 we gained specific check-llvm-* build targets for invoking
specific parts of the test suite, but they were copying the
dependencies for check-all, rather than just listing the dependencies
for check-llvm.

This moves the creation of these targets next to the check-llvm
target, and uses that target's configuration rather than the check-all
config.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233174 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-25 08:07:47 +00:00
Rafael Espindola
544763dcba Fix build.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233171 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-25 04:36:20 +00:00
Craig Topper
5238b7f47a [X86] Remove GetCpuIDAndInfo, GetCpuIDAndInfoEx and DetectFamilyModel functions from X86 MC layer. They haven't been used since CPU autodetection was removed from X86Subtarget.cpp.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233170 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-25 04:16:50 +00:00
Lang Hames
afb57c0251 [Orc] Remove extraneous 'typename'. This should cheer the bots up.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233168 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-25 04:00:34 +00:00
Lang Hames
339fa95661 [Orc] Refactor JITCompileCallbackManagerBase and CompileOnDemandLayer to support
target-independent callback management.

This is a prerequisite for adding orc-based lazy-jitting to lli.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233166 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-25 02:45:50 +00:00
Duncan P. N. Exon Smith
2186876e87 Linker: Temporarily disable dwarfdump checks from r233164
At least one Linux bot [1] doesn't like my dwarfdump checks, so I've
disable those until I can investigate what's going on there.  I'll
continue to track this in PR22792.

[1]: http://bb.pgr.jp/builders/cmake-llvm-x86_64-linux/builds/22863

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233165 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-25 02:43:04 +00:00
Duncan P. N. Exon Smith
c89369a941 Linker: Drop function pointers for overridden subprograms
Instead of dropping subprograms that have been overridden, just set
their function pointers to `nullptr`.  This is a minor adjustment to the
stop-gap fix for PR21910 committed in r224487, and fixes the crasher
from PR22792.

The problem that r224487 put a band-aid on: how do we find the canonical
subprogram for a `Function`?  Since the backend currently relies on
`DebugInfoFinder` (which does a naive in-order traversal of compile
units and picks the first subprogram) for this, r224487 tried dropping
non-canonical subprograms.

Dropping subprograms fails because the backend *also* builds up a map
from subprogram to compile unit (`DwarfDebug::SPMap`) based on the
subprogram lists.  A missing subprogram causes segfaults later when an
inlined reference (such as in this testcase) is created.

Instead, just drop the `Function` pointer to `nullptr`, which nicely
mirrors what happens when an already-inlined `Function` is optimized
out.  We can't really be sure that it's the same definition anyway, as
the testcase demonstrates.

This still isn't completely satisfactory.  Two flaws at least that I can
think of:

  - I still haven't found a straightforward way to make this symmetric
    in the IR.  (Interestingly, the DWARF output is already symmetric,
    and I've tested for that to be sure we don't regress.)
  - Using `DebugInfoFinder` to find the canonical subprogram for a
    function is kind of crazy.  We should just attach metadata to the
    function, like this:

        define weak i32 @foo(i32, i32) !dbg !MDSubprogram(...) {

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233164 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-25 02:26:32 +00:00
Chandler Carruth
ef81f7c255 [ADT] Teach MapVector to support a swap member. Will be used in
a subsequent commit in Clang.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233159 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-25 00:50:21 +00:00
Rafael Espindola
41509f4261 Fix warning on non-assert build.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233158 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-25 00:45:41 +00:00
Rafael Espindola
49dba99a89 Produce an error instead of asserting on invalid .sleb128/.uleb128.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233155 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-25 00:25:37 +00:00
Paul Robinson
759015d80f 'optnone' should not disable DAG combiner.
Reverts the code change from r221168 and the relevant test.
It was a mistake to disable the combiner, and based on the ultimate
definition of 'optnone' we shouldn't have considered the test case
as failing in the first place.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233153 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-25 00:10:24 +00:00
Philip Reames
c50bf46a22 !invariant.load semantics with potentially clobbering calls
A load from an invariant location is assumed to not alias any otherwise potentially aliasing stores. Our implementation only applied this rule to store instructions themselves whereas they it should apply for any memory accessing instruction. This results in both FRE and PRE becoming more effective at eliminating invariant loads.

Note that as a follow on change I will likely move this into AliasAnalysis itself. That's where the TBAA constant flag is handled and the semantics are essentially the same. I'd like to separate the semantic change from the refactoring and thus have extended the hack that's already in MemoryDependenceAnalysis for this change.

Differential Revision: http://reviews.llvm.org/D8591



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233140 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 23:54:54 +00:00
Rafael Espindola
4e86f54fdb Don't be over eager in evaluating a subtraction with a weak symbol.
In a subtraction of the form A - B, if B is weak, there is no way to represent
that on ELF since all relocations add the value of a symbol.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233139 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 23:48:44 +00:00
Reid Kleckner
d639e1975d X86: Fix frameescape when not using an FP
We can't use TargetFrameLowering::getFrameIndexOffset directly, because
Win64 really wants the offset from the stack pointer at the end of the
prologue. Instead, use X86FrameLowering::getFrameIndexOffsetFromSP(),
which is a pretty close approximiation of that. It fails to handle cases
with interestingly large stack alignments, which is pretty uncommon on
Win64 and is TODO.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233137 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 23:46:01 +00:00
Justin Bogner
fa71fb34ad Update a test I missed in r233132
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233134 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 23:44:03 +00:00
Andrew Kaylor
1e4e27a7a6 Disabling warnings for MSVC build to enable /W4 use.
Differential Revision: http://reviews.llvm.org/D8572



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233133 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 23:37:10 +00:00
Justin Bogner
b9e97c799e llvm-cov: Require a subcommand when invoked as llvm-cov
A while ago llvm-cov gained support for clang's instrumentation based
profiling in addition to its gcov support, and subcommands were added
to choose which behaviour to use. When no subcommand was specified, we
fell back to gcov compatibility with a warning that a subcommand would
be required in the future. Now, we require the subcommand.

Note that if the basename of llvm-cov is gcov (via symlink or
hardlink, for example), we still use the gcov compatible behaviour
with no subcommand required.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233132 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 23:34:36 +00:00
David Blaikie
4e933df738 Opaque Pointer Types: GEP API migrations to specify the gep type explicitly
The changes to InstCombine (& SCEV) do seem a bit silly - it doesn't make
anything obviously better to have the caller access the pointers element
type (the thing I'm trying to remove) than the GEP itself, but it's a
helpful migration step. This will allow me to more obviously lock down
GEP (& Load, etc) API usage, then fix all the code that accesses pointer
element types except the places that need to be removed (most of the
InstCombines) anyway - at which point I'll need to just remove all that
code because it won't be meaningful anymore (there will be no pointer
types, so no bitcasts to combine)

SCEV looks like it'll need some restructuring - we'll have to do a bit
more work for GEP canonicalization, since it'll depend on how it's used
if we can even manage to canonicalize it to a non-ugly GEP. I guess we
can do some fun stuff like voting (do 2 out of 3 load from the GEP with
a certain type that gives a pretty GEP? Does every typed use of the GEP
use either a specific type or a generic type (i8*, etc)?)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233131 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 23:34:31 +00:00
Frederic Riss
28b71b1917 [dsymutil] Temporarily disable some tests on windows.
It seems one windows bot fails since I added ilne table linking to
llvm-dsymutil (see r232333 commit thread).
Disable the affected tests until I can figure out what's happening.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233130 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 23:11:07 +00:00
Sanjay Patel
14c1d068a3 optimize the AVX2 (integer) version of vperm2 into a shuffle
...because this is what happens when an instruction
set puts its underwear on after its pants.

This is an extension of r232852, r233100, and 233110:
http://llvm.org/viewvc/llvm-project?view=revision&revision=232852
http://llvm.org/viewvc/llvm-project?view=revision&revision=233100
http://llvm.org/viewvc/llvm-project?view=revision&revision=233110



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233127 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 22:39:29 +00:00
David Blaikie
dad4e9cde6 Opaque Pointer Types: GEP API migrations to specify the gep type explicitly
The changes to InstCombine do seem a bit silly - it doesn't make
anything obviously better to have the caller access the pointers element
type (the thing I'm trying to remove) than the GEP itself, but it's a
helpful migration step. This will allow me to more obviously lock down
GEP (& Load, etc) API usage, then fix all the code that accesses pointer
element types except the places that need to be removed (most of the
InstCombines) anyway - at which point I'll need to just remove all that
code because it won't be meaningful anymore (there will be no pointer
types, so no bitcasts to combine)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233126 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 22:38:16 +00:00
Philip Reames
6bde9f6994 Merge empty landing pads in SimplifyCFG
This patch tries to merge duplicate landing pads when they branch to a common shared target.

Given IR that looks like this:
lpad1:
  %exn = landingpad {i8*, i32} personality i32 (...)* @__gxx_personality_v0
         cleanup
  br label %shared_resume
lpad2:
  %exn2 = landingpad {i8*, i32} personality i32 (...)* @__gxx_personality_v0
          cleanup
  br label %shared_resume
shared_resume:
  call void @fn()
  ret void
}

We can rewrite the users of both landing pad blocks to use one of them. This will generally allow the shared_resume block to be merged with the common landing pad as well.

Without this change, tail duplication would likely kick in - creating N (2 in this case) copies of the shared_resume basic block.

Differential Revision: http://reviews.llvm.org/D8297



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233125 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 22:28:45 +00:00
Rafael Espindola
54ce82e497 Add -m -m elf_x86_64 to gold invocations.
Otherwise the tests would fail if the default was not elf_x86_64.

This fixes PR22966.

Patch by H.J. Lu!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233124 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 22:20:19 +00:00
David Blaikie
ef9962d9bb Revert "Remove an InstCombine that seems to have become redundant."
Assertion fires in compiler-rt. Guess it does fire..

This reverts commit r233116.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233121 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 21:50:35 +00:00
Rafael Espindola
45eaa023df Reset the CFA offset at the start of every FDE.
This fixes PR21515.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233120 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 21:47:31 +00:00
Peter Collingbourne
4b8dfba3a1 AArch64: use a different means to determine whether to byte swap relocations.
This code depended on a bug in the FindAssociatedSection function that would
cause it to return the wrong result for certain absolute expressions. Instead,
use EvaluateAsRelocatable.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233119 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 21:47:03 +00:00
Peter Collingbourne
f99b7d0538 MC: Add more stringent symbol checking to test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233118 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 21:47:00 +00:00
David Blaikie
80da8623a4 Remove an InstCombine that seems to have become redundant.
Assert that this doesn't fire - I'll remove all of this later, but just
leaving it in for a while in case this is firing & we just don't have
test coverage.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233116 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 21:31:31 +00:00
Sanjay Patel
5e0ce9d13a [X86, AVX] instcombine vperm2 intrinsics with zero inputs into shuffles
This is the IR optimizer follow-on patch for D8563: the x86 backend patch
that converts this kind of shuffle back into a vperm2.

This is also a continuation of the transform that started in D8486. 
In that patch, Andrea suggested that we could convert vperm2 intrinsics that
use zero masks into a single shuffle. 

This is an implementation of that suggestion.

Differential Revision: http://reviews.llvm.org/D8567



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233110 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 20:36:42 +00:00
Rafael Espindola
71be19dff2 [llvm-readobj] add support for macho universal binary.
Patch by Keyue Hu (Chilledheart)!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233107 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 20:26:55 +00:00
Hans Wennborg
f61cd8b368 Revert r233062 ""float2int": Add a new pass to demote from float to int where possible."
This caused PR23008, compiles failing with: "Use still stuck around after Def is
destroyed: %.sroa.speculated"

Also reverting follow-up r233064.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233105 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 20:07:08 +00:00
Sanjoy Das
fe1187ead7 [IRCE] Fix how IRCE checks for no-sign-overflow.
IRCE requires the induction variables it handles to not sign-overflow.
The current scheme of checking if sext({X,+,S}) == {sext(X),+,sext(S)}
fails when SCEV simplifies sext(X) too.  After this change we //also//
check no-signed-wrap by looking at the flags set on the SCEVAddRecExpr.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233102 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 19:29:22 +00:00
Sanjoy Das
33a864aae2 [IRCE] Fix a regression introduced in r232444.
IRCE should not try to eliminate range checks that check an induction
variable against a loop-varying length.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233101 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 19:29:18 +00:00
Sanjay Patel
fe76881930 [X86, AVX] recognize shufflevector with zero input as a vperm2 (PR22984)
vperm2x128 instructions have the special ability (aka free hardware capability)
to shuffle zero values into a vector.

This patch recognizes that type of shuffle and generates the appropriate
control byte.

https://llvm.org/bugs/show_bug.cgi?id=22984

Differential Revision: http://reviews.llvm.org/D8563



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233100 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 19:19:07 +00:00
Duncan P. N. Exon Smith
1329ecfc78 DebugInfo: Reorder definitions of MDLocation and MDFile, NFC
Move definition of `MDLocation` after `MDLocalScope` so that the latter
is available for casts in the former.  Similarly, move the definition of
`MDFile` as early as possible so that other classes can cast to it in
their definitions.  (Follow-up commits will take advantage of this.)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233096 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 17:34:33 +00:00
Duncan P. N. Exon Smith
15a873a6e2 Verifier: Start recursing into !dbg attachments
The main verifier already recurses through the other entry points, so we
might as well descend here too.

This temporarily duplicates some work already done in
`verifyDebugInfo()`, but eventually I'll be removing the other side.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233095 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 17:32:19 +00:00
Duncan P. N. Exon Smith
eeb2ba6d46 Verifier: !llvm.dbg.cu must point at compile units
Duplicate this check from `verifyDebugInfo()`.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233094 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 17:18:03 +00:00
Duncan P. N. Exon Smith
ab10069039 DebugInfo: Add MDLocalScope, a legal scope for locals
Add a subclass of `MDScope` to explicitly categorize the legal scopes
for locals -- in particular, scopes that are legal for `MDLocation`,
`MDLexicalBlockBase`, and `MDLocalVariable`.  This provides a convenient
`isa<>` target for the verifier, and eventually I'll be changing the
above classes' `getScope()` to specifically return it.  Currently, its
subclasses are `MDSubprogram`, `MDLexicalBlock`, and
`MDLexicalBlockFile`.

I've gone with `MDLocalScope` for now -- a little ambiguous since it's a
scope *for* locals, not a scope that's local -- but I'm open to more
descriptive names if someone can think of something better.  Regardless,
the code docs should make it clear enough.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233092 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 16:44:29 +00:00