Commit Graph

116331 Commits

Author SHA1 Message Date
Vladimir Sukharev
d1e387b9e6 [AArch64] LORID_EL1 register must be treated as read-only
Patch by: John Brawn

Reviewers: jmolloy

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D9105


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235314 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-20 16:54:37 +00:00
Akira Hatanaka
ca9313e65e [InlineFunction] Don't add lifetime markers for zero-sized allocas.
This commit fixes the code which adds lifetime markers in InlineFunction to skip
zero-sized allocas instead of asserting on them.

rdar://problem/20531155


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235312 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-20 16:11:05 +00:00
Brendon Cahoon
d9b36e1007 Recognize n/1 in the SCEV divide function
n/1 generates a quotient equal to n and a remainder of 0.
If this case is not recognized, then the SCEV divide() function
can return a remainder that is greater than or equal to the
denominator, which means the delinearized subscripts for the
test case will be incorrect.

Differential Revision: http://reviews.llvm.org/D9003


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235311 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-20 16:03:28 +00:00
Bill Schmidt
70273be423 [PowerPC] Flow oversized lines for r235309
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235310 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-20 15:58:46 +00:00
Bill Schmidt
54f902e367 [PowerPC] Add future work for vector insert/extract to README_ALTIVEC.txt
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235309 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-20 15:54:26 +00:00
Jozef Kolek
fc4915076f [mips][microMIPSr6] Implement disassembler support
Implement disassembler support for microMIPS32r6.

Differential Revision: http://reviews.llvm.org/D8490


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235307 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-20 14:40:38 +00:00
Rafael Espindola
f30ac8f5ec Don't allow pwrite to resize a stream.
The current implementations could exhibit some behavior differences:

raw_fd_ostream: Whatever the underlying fd does with seek+write. In a normal
file, the write position would be back to the old offset.

raw_svector_ostream: The write position is always the end of the stream, so
after pwrite the write position would be the new end. This matches what OS_X
(all BSD?) do with a pwrite in a O_APPEND fd.

Given that we don't need that feature and don't use O_APPEND a lot in LLVM,
just disallow it.

I am open to suggestions on renaming pwrite to something else, but this fixes
the issue for now.

Thanks to Yaron Keren for reporting it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235303 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-20 13:04:30 +00:00
Jozef Kolek
dbef0175c3 [mips][microMIPSr6] Implement BALC and BC instructions
This patch implements BALC and BC instructions using mapping.

Differential Revision: http://reviews.llvm.org/D8388


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235302 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-20 13:04:14 +00:00
Rafael Espindola
ca3837369f Look past locals in comdats.
We have to avoid converting a reference to a global into a reference to a local,
but it is fine to look past a local.

Patch by Vasileios Kalintiris.

I just moved the comment and added thet test.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235300 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-20 12:44:06 +00:00
Jozef Kolek
7ab9941632 [mips][microMIPSr6] Implement initial mapping support
Differential Revision: http://reviews.llvm.org/D8387


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235298 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-20 12:42:08 +00:00
Jozef Kolek
ec47ed84d2 [mips][microMIPSr6] Implement initial subtarget support
Differential Revision: http://reviews.llvm.org/D8386


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235296 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-20 12:23:06 +00:00
Andrea Di Biagio
14fc08301c [X86][FastIsel] Fix assertion failure when selecting int-to-double conversion (PR23273).
This fixes a regression introduced at revision 231243.
The target-independent selection algorithm in FastISel knows how to select
a SINT_TO_FP if the target is SSE but not AVX. That is because on X86, the
tablegen'd 'fastEmit' functions know how to select CVTSI2SSrr and CVTSI2SDrr.

Method X86FastISel::X86SelectSIToFP was therefore working under the
wrong assumption that the target was AVX. That assumption was incorrect since
we can have a target that is neither AVX nor SSE.

So, rather than asserting for the presence of AVX, we should have had an
early exit from 'X86SelectSIToFP' if the target was not AVX.
This patch fixes the issue replacing the invalid assertion with an early exit.

Thanks to Dimitry Andric for reporting this problem and for providing a small
reproducible testcase. Added test pr23273.ll.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235295 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-20 11:56:59 +00:00
Karthik Bhat
07bfae5ff7 Fix buildbot failure on darwin from r235284.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235287 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-20 07:07:10 +00:00
Simon Atanasyan
23d47d346d [Mips] Support DT_MIPS_OPTIONS dynamic section tag in the llvm-readobj
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235285 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-20 05:34:48 +00:00
Karthik Bhat
b2fd516ed9 [NFC] Refactor identification of reductions as common utility function.
This patch refactors reduction identification code out of LoopVectorizer and
exposes them as common utilities.
No functional change.
Review: http://reviews.llvm.org/D9046



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235284 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-20 04:38:33 +00:00
Hal Finkel
6809724935 [InlineAsm] Remove EarlyClobber on registers that are also inputs
When an inline asm call has an output register marked as early-clobber, but
that same register is also an input operand, what should we do? GCC accepts
this, and is documented to accept this for read/write operands saying,
"Furthermore, if the earlyclobber operand is also a read/write operand, then
that operand is written only after it's used." For write-only operands, the
situation seems less clear, but I have at least one existing codebase that
assumes this will work, in part because it has syscall macros like this:

({                                                                         \
  register uint64_t r0 __asm__ ("r0") = (__NR_ ## name);                   \
  register uint64_t r3 __asm__ ("r3") = ((uint64_t) (arg0));               \
  register uint64_t r4 __asm__ ("r4") = ((uint64_t) (arg1));               \
  register uint64_t r5 __asm__ ("r5") = ((uint64_t) (arg2));               \
  __asm__ __volatile__                                                     \
  ("sc"                                                                    \
   : "=&r"(r0),"=&r"(r3),"=&r"(r4),"=&r"(r5)                               \
   :   "0"(r0),  "1"(r3),  "2"(r4),  "3"(r5)                               \
   : "r6","r7","r8","r9","r10","r11","r12","cr0","memory");                \
  r3;                                                                      \
})

Furthermore, with register aliases and subregister relationships that only the
backend knows about, rejecting this in the frontend seems like a difficult
proposition (if we wanted to do so). However, keeping the early-clobber flag on
the INLINEASM MI does not work for us, because it will cause the register's
live interval to end to soon (so it will not appear defined to be used as an
input).

Fortunately, fixing this does not seem hard: When forming the INLINEASM MI,
check to see if any of the early-clobber outputs are also inputs, and if so,
remove the early-clobber flag.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235283 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-20 00:01:30 +00:00
Simon Pilgrim
ca3e6fafc8 [X86][SSE] Fix for getScalarValueForVectorElement to detect scalar sources requiring truncation.
The fix ensures that scalar sources inserted into a vector are the correct bit size.

Integer scalar sources from BUILD_VECTOR and SCALAR_TO_VECTOR nodes may require truncation that this function doesn't currently support.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235281 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-19 22:16:49 +00:00
Simon Pilgrim
e398eb753a [X86][SSE] Extended copysign tests to include llvm intrinsic implementation and constant folding.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235279 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-19 21:34:57 +00:00
Simon Atanasyan
a039f1779d [mips] Update MIPS relocations list
No functional changes.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235278 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-19 20:51:55 +00:00
Eric Christopher
7db13c42c3 Remove the FCFI option from TargetOptions as it is currently unused.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235269 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-19 03:21:08 +00:00
Eric Christopher
46e3c5a0f7 Remove CFIFuncName from TargetOptions as it is currently unused.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235268 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-19 03:21:04 +00:00
Eric Christopher
b9765d2fa0 Remove the CFIEnforcing flag from TargetOptions as it is unused.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235267 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-19 03:20:59 +00:00
Eric Christopher
1b1dbcda43 Remove the CFIType TargetOption as it is unused.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235266 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-19 03:20:55 +00:00
Eric Christopher
03f27348a2 Remove the JITEmitDebugInfo TargetOptions as they're only set and
not used anywhere in llvm.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235265 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-19 03:20:51 +00:00
Craig Topper
6fa7febee4 Remove unnecessary include and probably a layering violation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235262 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-19 00:57:33 +00:00
Ahmed Bougacha
3a65b111b5 [MemCpyOpt] Don't force i64 when promoting memset/memcpy sizes.
Harden r235258 to support any integer bitwidth.  The quick glance at
the reference made me think only i32 and i64 were valid types, but
they're not special, so any overload is legal.

Thanks to David Majnemer for noticing!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235261 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-18 23:06:04 +00:00
Simon Pilgrim
4ac6a63687 [X86][AVX2] Force execution domain on broadcast folding tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235260 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-18 21:24:16 +00:00
Simon Pilgrim
48ef68c206 [X86][SSE] Force execution domain on float/double unpack shuffle tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235259 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-18 18:50:55 +00:00
Ahmed Bougacha
ebb4371478 [MemCpyOpt] Promote both memset/memcpy sizes if differently typed.
Followup to r235232, which caused PR23278.

We can't assume the memset and memcpy sizes have the same type, as
nothing in the language reference prevents that.
Instead, zext both to i64 if they disagree.

While there, robustify tests by using i8 %c rather than i8 0 for the
memset character.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235258 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-18 17:57:41 +00:00
Benjamin Kramer
339bc7faf0 [InstCombine] Create zero constants on demand.
No functional change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235257 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-18 16:52:08 +00:00
David Majnemer
c5edbea4e7 [InstCombine] (mul nsw 1, INT_MIN) != (shl nsw 1, 31)
Multiplying INT_MIN by 1 doesn't trigger nsw.  However, shifting 1 into
the sign bit *does* trigger nsw.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235250 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-18 04:41:30 +00:00
Ahmed Bougacha
35e8055393 [GlobalMerge] Look at uses to create smaller global sets.
Instead of merging everything together, look at the users of
GlobalVariables, and try to group them by function, to create
sets of globals used "together".

Using that information, a less-aggressive alternative is to keep merging
everything together *except* globals that are only ever used alone, that
is, those for which it's clearly non-profitable to merge with others.

In my testing, grouping by Function is too aggressive, but grouping by
BasicBlock is too conservative.  Anything in-between isn't trivially
available, so stick with Function grouping for now.

cl::opts are added for testing; both enabled by default.

A few of the testcases aren't testing the merging proper, but just
various edge cases when merging does occur.  Update them to use the
previous grouping behavior. Also, one of the tests is unrelated to
GlobalMerge; change it accordingly.
While there, switch to r234666' flags rather than the brutal -O3.

Differential Revision: http://reviews.llvm.org/D8070


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235249 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-18 01:21:58 +00:00
Duncan P. N. Exon Smith
20b39c653c DebugInfo: Delete DIDescriptor (but not its subclasses)
Delete `DIDescriptor` and update the remaining users.  I'll follow-up by
deleting subclasses in manageable groups (top-down).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235248 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-18 00:35:36 +00:00
Duncan P. N. Exon Smith
603fc8c265 docs: Update Kaleidoscope for recent DI changes
This has been bit-rotting, so fix it up.  I'll have to edit this again
once the MD* classes have been renamed to DI* -- I'll try to remember to
do that with the commit that renames them.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235244 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-18 00:01:35 +00:00
Ahmed Bougacha
6b96a388ed [AArch64] Don't force MVT::Untyped when selecting LD1LANEpost.
The result is either an Untyped reg sequence, on ldN with N > 1, or
just the type of the input vector, on ld1.  Don't force Untyped.
Instead, just use the type of the reg sequence.

This mirrors the behavior of createTuple, which feeds the LD1*_POST.

The narrow code path wasn't actually covered by tests, because V64
insert_vector_elt are widened to V128 before the LD1LANEpost combine
has the chance to run, usually.

The only case where it does run on V64 vectors is if the vector ops
legalizer ran.  So, tickle the code with a ctpop.

Fixes PR23265.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235243 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-17 23:43:33 +00:00
Ahmed Bougacha
ab017cbc27 Fix another typo in r235224 testcase. NFC.
Third time's the charm!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235242 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-17 23:38:46 +00:00
Andrew Kaylor
fe98bed792 Fix build wanrings and line endings
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235241 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-17 23:20:24 +00:00
Duncan P. N. Exon Smith
5d801364e2 DebugInfo: Remove DIDescriptor from the DebugInfo API
Stop using `DIDescriptor` and its subclasses in the `DebugInfoFinder`
API, as well as the rest of the API hanging around in `DebugInfo.h`.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235240 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-17 23:20:10 +00:00
Andrew Kaylor
166679ef06 [WinEH] Fixes for a few cppeh failures.
Differential Review: http://reviews.llvm.org/D9065



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235239 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-17 23:05:43 +00:00
Adam Nemet
ee5f9c6278 [LoopAccesses] Improve debug output
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235238 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-17 22:43:10 +00:00
Zachary Turner
9d74bda3e3 [PDB] Support executables and source/line info.
Previously DebugInfoPDB could only load data for a PDB given a
path to the PDB.  It could not open an EXE and find the matching
PDB and verify it matched, etc.  This patch adds support for that
so that we can simply load debug information for a PDB directly.

Additionally, this patch extends DebugInfoPDB to support getting
source and line information for symbols.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235237 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-17 22:40:36 +00:00
David Blaikie
4ba5d91a08 [opaque pointer type] Access the pointee of the result type from the GEP rather than pulling it out of the pointer result type
The implementation of this GEP::getResultElementType will be refactored
to either rely on a member variable, or recompute the value from the
indicies (any preferences?).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235236 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-17 22:32:20 +00:00
David Blaikie
1b44f585f9 [opaque pointer type] Query the GEP for its source element type directly rather than finding it through the pointer type of the first operand in the Verifier
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235235 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-17 22:32:17 +00:00
David Blaikie
40294c3e49 [opaque pointer type] Avoid creating (and then unwrapping) a pointer type to compute the result type of a GEP
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235234 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-17 22:32:16 +00:00
David Blaikie
72981cdce3 [opaque pointer type] Use the parsed explicit pointee type when error-checking geps during LL parsing
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235233 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-17 22:32:13 +00:00
Ahmed Bougacha
7349765ddb [MemCpyOpt] Optimize double-storing by memset+memcpy.
A common idiom in some code is to do the following:

  memset(dst, 0, dst_size);
  memcpy(dst, src, src_size);

Some of the memset is redundant; instead, we can do:

  memcpy(dst, src, src_size);
  memset(dst + src_size, 0,
         dst_size <= src_size ? 0 : dst_size - src_size);

Original patch by: Joel Jones
Differential Revision: http://reviews.llvm.org/D498


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235232 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-17 22:20:57 +00:00
Sean Silva
586a785efc [LangRef] Remove redundant and inconsistent condition.
Just above, 'op2' is stated to be unsigned, so 'negative' doesn't make
sense (and is handled by "larger than" anyway). The descriptions for
lshr and ashr don't say 'negative or' either.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235230 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-17 21:58:55 +00:00
Duncan P. N. Exon Smith
1186e7ae9e AsmPrinter: Create a unified .debug_loc stream
This commit removes `DebugLocList` and replaces it with
`DebugLocStream`.

  - `DebugLocEntry` no longer contains its byte/comment streams.
  - The `DebugLocEntry` list for a variable/inlined-at pair is allocated
    on the stack, and released right after `DebugLocEntry::finalize()`
    (possible because of the refactoring in r231023).  Now, only one
    list is in memory at a time now.
  - There's a single unified stream for the `.debug_loc` section that
    persists, stored in the new `DebugLocStream` data structure.

The last point is important: this collapses the nested `SmallVector<>`s
from `DebugLocList` into unified streams.  We previously had something
like the following:

    vec<tuple<Label, CU,
              vec<tuple<BeginSym, EndSym,
                        vec<Value>,
                        vec<char>,
                        vec<string>>>>>

A `SmallVector` can avoid allocations, but is statically fairly large
for a vector: three pointers plus the size of the small storage, which
is the number of elements in small mode times the element size).
Nesting these is expensive, since an inner vector's size contributes to
the element size of an outer one.  (Nesting any vector is expensive...)

In the old data structure, the outer vector's *element* size was 632B,
excluding allocation costs for when the middle and inner vectors
exceeded their small sizes.  312B of this was for the "three" pointers
in the vector-tree beneath it.  If you assume 1M functions with an
average of 10 variable/inlined-at pairs each (in an LTO scenario),
that's almost 6GB (besides inner allocations), with almost 3GB for the
"three" pointers.

This came up in a heap profile a little while ago of a `clang -flto -g`
bootstrap, with `DwarfDebug::collectVariableInfo()` using something like
10-15% of the total memory.

With this commit, we have:

    tuple<vec<tuple<Label, CU, Offset>>,
          vec<tuple<BeginSym, EndSym, Offset, Offset>>,
          vec<char>,
          vec<string>>

The offsets are used to create `ArrayRef` slices of adjacent
`SmallVector`s.  This reduces the number of vectors to four (unrelated
to the number of variable/inlined-at pairs), and caps the number of
allocations at the same number.

Besides saving memory and limiting allocations, this is NFC.

I don't know my way around this code very well yet, but I wonder if we
could go further: why stream to a side-table, instead of directly to the
output stream?

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235229 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-17 21:34:47 +00:00
Pete Cooper
12a57fe1d3 AArch64: Add test for returning [2 x i64] in registers. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235228 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-17 21:31:25 +00:00
Rafael Espindola
fb118bd226 Compute A-B when A or B is weak.
Similar to r235222, but for the weak symbol case.

In an "ideal" assembler/object format an expression would always refer to the
final value and A-B would only be computed from a section in the same
comdat as A and B with A and B strong.

Unfortunately that is not the case with debug info on ELF, so we need an
heuristic.  Since we need an heuristic, we may as well use the same one as
gas:

* call weak_sym : produces a relocation, even if in the same section.
* A - weak_sym and weak_sym -A: don't produce a relocation if we can
  compute it.

This fixes pr23272 and changes the fix of pr22815 to match what gas does.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235227 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-17 21:15:17 +00:00