Commit Graph

12625 Commits

Author SHA1 Message Date
Michael Kuperstein
8f260e3084 Fixes a bug in vector load legalization that confused bits and bytes.
Differential Revision: http://reviews.llvm.org/D7400

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228168 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-04 18:54:01 +00:00
Colin LeMahieu
47d6e4d009 [Hexagon] Adding encoding information for absolute-reg mode stores. Xfailing a test until constant extenders are correctly put in the same packet.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228158 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-04 17:52:06 +00:00
Zoran Jovanovic
8dc0ae6606 [mips][microMIPS] Implement CodeGen support for SW16 and LW16 instructions
Differential Revision: http://reviews.llvm.org/D6581


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228149 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-04 15:43:17 +00:00
Daniel Sanders
712010f655 [mips] Remove unused check prefix from tests. NFC.
Reviewers: vmedic

Reviewed By: vmedic

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D7376

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228145 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-04 14:48:39 +00:00
Renato Golin
0966a4e370 Adding support to LLVM for targeting Cortex-A72
Currently, Cortex-A72 is modelled as an Cortex-A57 except the fp
load balancing pass isn't enabled for Cortex-A72 as it's not
profitable to have it enabled for this core.

Patch by Ranjeet Singh.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228140 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-04 13:31:29 +00:00
Chandler Carruth
b0589710cc [x86] Give movss and movsd execution domains in the x86 backend.
This associates movss and movsd with the packed single and packed double
execution domains (resp.). While this is largely cosmetic, as we now
don't have weird ping-pong-ing between single and double precision, it
is also useful because it avoids the domain fixing algorithm from seeing
domain breaks that don't actually exist. It will also be much more
important if we have an execution domain default other than packed
single, as that would cause us to mix movss and movsd with integer
vector code on a regular basis, a very bad mixture.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228135 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-04 10:58:53 +00:00
Chandler Carruth
886bbe2d76 [x86] Remove a low-value test that was just checking how we cleared
a register. We have lots of tests covering this.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228133 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-04 10:47:34 +00:00
Chandler Carruth
424a198c30 [x86] Mechanically update a bunch of tests' check lines using the latest
version of the script.

Changes include:
- Using the VEX prefix
- Skipping more detail when we have useful shuffle comments to match
- Matching more shuffle comments that have been added to the printer
  (yay!)
- Matching the destination registers of some AVX instructions
- Stripping trailing whitespace that crept in
- Fixing indentation issues

Nothing interesting going on here. I'm just trying really hard to ensure
these changes don't show up in the diffs with actual changes to the
backend.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228132 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-04 10:46:53 +00:00
Renato Golin
ff01f89466 Reverting VLD1/VST1 base-updating/post-incrementing combining
This reverts patches 223862, 224198, 224203, and 224754, which were all
related to the vector load/store combining and were reverted/reaplied
a few times due to the same alignment problems we're seeing now.

Further tests, mainly self-hosting Clang, will be needed to reapply this
patch in the future.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228129 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-04 10:11:59 +00:00
Chandler Carruth
d16b9cd3d4 [x86] Include the destination register in the check-lines for AVX
instructions.

No actual change here.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228127 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-04 09:18:27 +00:00
Chandler Carruth
82b686e611 [x86] Add some tests I missed in the prior commit to cover blends with
zero for v8i16 as well.

These exhibit the same domain badness, but also exhibit other weaknesses
in our blend lowering. More fixes to come.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228126 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-04 09:15:46 +00:00
Chandler Carruth
da681cc578 [x86] Start to introduce bit-masking based blend lowering.
This is the simplest form of bit-math based blending which only fires
when we are blending with zero and is relatively profitable. I've only
enabled this path on very specific lowering strategies. I'm planning to
widen its applicability in subsequent patches, but so far you'll notice
that even though we get fewer shufps instructions, we *still* do the bit
math in the FP execution port. I'm looking into why this is still
happening.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228124 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-04 09:06:05 +00:00
Chandler Carruth
6b1eacb0b5 [x86] Add tests for blends-with-zero on 4-element vectors.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228122 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-04 09:05:58 +00:00
Bill Schmidt
89e8a17b4d [PowerPC] Handle 32-bit targets properly in PPCTLSDynamicCall.cpp
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228116 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-04 05:51:56 +00:00
Chandler Carruth
786f55c1fb [x86] Refresh the checks of a number of tests using
update_llc_test_checks.py.

The exact format of the checks has changed over time. This includes
different indenting rules, new shuffle comments that have been added,
and more operand hiding behind regular expressions.

No functional change to the tests are expected here, but this will make
subsequent patches have a clean diff as they change shuffle lowering.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228097 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-04 00:58:42 +00:00
Chandler Carruth
18ee73e456 [x86] Switch to using the long '--check-prefix' form which the
update_llc_test_checks.py script uses, and refresh the checks in this
test.

No functionality changed here, just bringing this test up to work with
automated updates using the python script.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228096 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-04 00:58:40 +00:00
Chandler Carruth
877ac0a034 [x86] Port this test to use utils/update_llc_test_checks.py.
This will make it easy to update as I change some parts of the X86
backend, makes it more clear what instruction differences are
introduced, and I find it makes it a bit easier to read as well.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228095 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-04 00:58:37 +00:00
Sanjay Patel
f1ac92a3b9 improved CHECK
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228086 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-04 00:24:06 +00:00
Simon Pilgrim
3d04e48cb6 [X86][SSE] psrl(w/d/q) and psll(w/d/q) bit shifts for SSE2
Patch to match cases where shuffle masks can be reduced to bit shifts. Similar to byte shift shuffle matching from D5699.

Differential Revision: http://reviews.llvm.org/D6649

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228047 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 21:58:29 +00:00
Chandler Carruth
2e3524ec17 [x86] Add two truly horrific test cases for the new vector shuffle
lowering. I'm prepping patches to improve these, and this will let the
delta of those patches show the improvement. =]

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228044 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 21:56:28 +00:00
Chandler Carruth
d5a61c2958 [x86] Update the indent and layout of some tests in this file. NFC
This is just to remove voise from using the update_llc_test_checks
script.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228043 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 21:56:24 +00:00
Marek Olsak
90eef42c8e R600/SI: Remove the -CHECK suffix from all FileCheck prefixes in LIT tests
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228040 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 21:53:27 +00:00
Marek Olsak
e1a8ca95be R600/SI: Fix B64 VALU shifts on VI
SI only has standard versions. VI only has REV versions.

Tested-by: Michel Dänzer <michel.daenzer@amd.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228037 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 21:53:01 +00:00
Chandler Carruth
dc5e49a1c4 [x86] Tweak my update script to use test case function names starting
with 'stress' to indicate that the specific output isn't interesting and
relax them to only check the last instruction (a ret).

I've updated the one test case that really uses this to name the one
'stress_test' which was actually producing output we can directly check.
With this, the script doesn't introduce noise when run over the v16 test
file.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228033 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 21:26:45 +00:00
Colin LeMahieu
3c159ed1a0 [Hexagon] Converting XTYPE/SHIFT intrinsics. Cleaning out old intrinsic patterns and updating tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228026 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 20:40:52 +00:00
Simon Pilgrim
646722d55f [X86][SSE] Added general integer shuffle matching for MOVQ instruction
This patch adds general shuffle pattern matching for the MOVQ zero-extend instruction (copy lower 64bits, zero upper) for all 128-bit integer vectors, it is added as a fallback test in lowerVectorShuffleAsZeroOrAnyExtend.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228022 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 20:09:18 +00:00
Colin LeMahieu
861e105e61 [Hexagon] Updating XTYPE/PRED intrinsics.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228019 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 19:43:59 +00:00
Colin LeMahieu
30f48c7dc4 [Hexagon] Updating XTYPE/PERM intrinsics.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228015 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 19:36:59 +00:00
Simon Pilgrim
71a4e9522e [X86][AVX2] Enabled shuffle matching for the AVX2 zero extension (128bit -> 256bit) vpmovzx* instructions.
Differential Revision: http://reviews.llvm.org/D7251

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228014 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 19:34:09 +00:00
Rafael Espindola
f4e2998eda Fix typo in test/CodeGen/X86/sibcall.ll (pr22331).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228011 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 19:20:26 +00:00
Colin LeMahieu
6217146dce [Hexagon] Adding missing vector multiply instruction encodings. Converting multiply intrinsics and updating tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228010 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 19:15:11 +00:00
Sanjay Patel
9b4cc76745 Merge consecutive 16-byte loads into one 32-byte load (PR22329)
This patch detects consecutive vector loads using the existing 
EltsFromConsecutiveLoads() logic. This fixes:
http://llvm.org/bugs/show_bug.cgi?id=22329

This patch effectively reverts the tablegen additions of D6492 / 
http://reviews.llvm.org/rL224344 ...which in hindsight were a horrible hack.

The test cases that were added with that patch are simply modified to load
from varying offsets of a base pointer. These loads did not match the existing
tablegen patterns.

A happy side effect of doing this optimization earlier is that we can now fold
the load into a math op where possible; this is shown in some of the updated
checks in the test file.

Differential Revision: http://reviews.llvm.org/D7303



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228006 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 18:54:00 +00:00
Colin LeMahieu
936986d12d [Hexagon] Converting complex number intrinsics and adding tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227995 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 18:16:28 +00:00
Colin LeMahieu
a3a588d983 [Hexagon] Adding vector intrinsics for alu32/alu and xtype/alu.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227993 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 18:01:45 +00:00
Marek Olsak
a95296a86e R600/SI: Don't generate non-existent LSHL, LSHR, ASHR B32 variants on VI
This can happen when a REV instruction is commuted.

The trick is not to define the _vi versions of instructions, which has these
consequences:
- code generation will always fail if a pseudo cannot be lowered
  (very useful to catch bugs where an unsupported instruction somehow makes
   it to the printer)
- ability to query if a pseudo can be lowered, which is done in commuteOpcode
  to prevent REV from commuting to non-REV on VI

Tested-by: Michel Dänzer <michel.daenzer@amd.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227990 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 17:38:12 +00:00
Marek Olsak
b19dbd9eb3 R600/SI: Fix dependency between instruction writing M0 and S_SENDMSG on VI (v2)
This fixes a hang when using an empty geometry shader.

v2: - don't add s_nop when followed by s_waitcnt
    - comestic changes

Tested-by: Michel Dänzer <michel.daenzer@amd.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227986 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 17:37:52 +00:00
Sanjay Patel
3cf9267d4e Fix program crashes due to alignment exceptions generated for SSE memop instructions (PR22371).
r224330 introduced a bug by misinterpreting the "FeatureVectorUAMem" bit.
The commit log says that change did not affect anything, but that's not correct.
That change allowed SSE instructions to have unaligned mem operands folded into
math ops, and that's not allowed in the default specification for any SSE variant. 

The bug is exposed when compiling for an AVX-capable CPU that had this feature
flag but without enabling AVX codegen. Another mistake in r224330 was not adding
the feature flag to all AVX CPUs; the AMD chips were excluded.

This is part of the fix for PR22371 ( http://llvm.org/bugs/show_bug.cgi?id=22371 ).

This feature bit is SSE-specific, so I've renamed it to "FeatureSSEUnalignedMem".
Changed the existing test case for the feature bit to reflect the new name and
renamed the test file itself to better reflect the feature.
Added runs to fold-vex.ll to check for the failing codegen.

Note that the feature bit is not set by default on any CPU because it may require a
configuration register setting to enable the enhanced unaligned behavior.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227983 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 17:13:04 +00:00
Bill Schmidt
aeba87d6a6 Disable 32-bit tests in tls-pic.ll until they can be repaired
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227981 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 16:57:38 +00:00
Bill Schmidt
b32d6f455f Further revise too-restrictive test CodeGen/PowerPC/tls-pic.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227980 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 16:33:55 +00:00
Bill Schmidt
f336df5f3f Further revise too-restrictive test CodeGen/PowerPC/tls-pic.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227978 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 16:29:52 +00:00
Bill Schmidt
5114e12df0 Revise too-restrictive test CodeGen/PowerPC/tls-pic.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227977 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 16:24:05 +00:00
Bill Schmidt
1123a81009 [PowerPC] Yet another approach to __tls_get_addr
This patch is a third attempt to properly handle the local-dynamic and
global-dynamic TLS models.

In my original implementation, calls to __tls_get_addr were hidden
from view until the asm-printer phase, at which point the underlying
branch-and-link instruction was created with proper relocations.  This
mostly worked well, but I used some repellent techniques to ensure
that the TLS_GET_ADDR nodes at the SD and MI levels correctly received
input from GPR3 and produced output into GPR3.  This proved to work
badly in the presence of multiple TLS variable accesses, with the
copies to and from GPR3 being scheduled incorrectly and generally
creating havoc.

In r221703, I addressed that problem by representing the calls to
__tls_get_addr as true calls during instruction lowering.  This had
the advantage of removing all of the bad hacks and relying on the
existing call machinery to properly glue the copies in place. It
looked like this was going to be the right way to go.

However, as a side effect of the recent discovery of problems with
linker optimizations for TLS, we discovered cases of suboptimal code
generation with this strategy.  The problem comes when tls_get_addr is
called for the same address, and there is a resulting CSE
opportunity.  It turns out that in such cases MachineCSE will common
the addis/addi instructions that set up the input value to
tls_get_addr, but will not common the calls themselves.  MachineCSE
does not have any machinery to common idempotent calls.  This is
perfectly sensible, since presumably this would be done at the IR
level, and introducing calls in the back end isn't commonplace.  In
any case, we end up with two calls to __tls_get_addr when one would
suffice, and that isn't good.

I presumed that the original design would have allowed commoning of
the machine-specific nodes that hid the __tls_get_addr calls, so as
suggested by Ulrich Weigand, I went back to that design and cleaned it
up so that the copies were properly held together by glue
nodes.  However, it turned out that this didn't work either...the
presence of copies to physical registers kept the machine-specific
nodes from being commoned also.

All of which leads to the design presented here.  This is a return to
the original design, except that no attempt is made to introduce
copies to and from GPR3 during instruction lowering.  Virtual registers
are used until prior to register allocation.  At that point, a special
pass is run that identifies the machine-specific nodes that hide the
tls_get_addr calls and introduces the copies to and from GPR3 around
them.  The register allocator then coalesces these copies away.  With
this design, MachineCSE succeeds in commoning tls_get_addr calls where
possible, and we get nice optimal code generation (better than GCC at
the moment, which does not common these calls).

One additional problem must be dealt with:  After introducing the
mentions of the physical register GPR3, the aggressive anti-dependence
breaker sees opportunities to improve scheduling by selecting a
different register instead.  Flags must be used on the instruction
descriptions to tell the anti-dependence breaker to keep its hands in
its pockets.

One thing missing from the original design was recording a definition
of the link register on the GET_TLS_ADDR nodes.  Doing this was found
to be insufficient to force a stack frame to be created, which led to
looping behavior because two different LR values were stored at the
same address.  This appears to have been an oversight in
PPCFrameLowering::determineFrameLayout(), which is repaired here.

Because MustSaveLR() returns true for calls to builtin_return_address,
this changed the expected behavior of
test/CodeGen/PowerPC/retaddr2.ll, which now stacks a frame but
formerly did not.  I've fixed the test case to reflect this.

There are existing TLS tests to catch regressions; the checks in
test/CodeGen/PowerPC/tls-store2.ll proved to be too restrictive in the
face of instruction scheduling with these changes, so I fixed that
up.

I've added a new test case based on the PrettyStackTrace module that
demonstrated the original problem. This checks that we get correct
code generation and that CSE of the calls to __get_tls_addr has taken
place.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227976 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 16:16:01 +00:00
Sanjay Patel
ec60318bf5 Improve test to actually check for a folded load.
This test was checking for lack of a "movaps" (an aligned load)
rather than a "movups" (an unaligned load). It also included
a store which complicated the checking.

Add specific CPU runs to prevent subtarget feature flag overrides
from inhibiting this optimization.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227972 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 15:37:18 +00:00
Bruno Cardoso Lopes
7df357f552 [X86][MMX] Improve transfer from mmx to i32
Improve EXTRACT_VECTOR_ELT DAG combine to catch conversion patterns
between x86mmx and i32 with more layers of indirection.

Before:
  movq2dq %mm0, %xmm0
  movd %xmm0, %eax
After:
  movd %mm0, %eax

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227969 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 14:46:49 +00:00
Alex Rosenberg
cba5c599e8 Revert part of r227437 as it was unnecessary. Thanks to echristo for
pointing this out.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227897 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-02 23:58:54 +00:00
Bruno Cardoso Lopes
d821e0a5cc [X86][MMX] Add tests for MMX extract element
LLVM ToT produces poor MMX code compared to 3.5. However, part of the previous
functionality can be achieved by using -x86-experimental-vector-widening-legalization.
Add tests to be sure we don't regress again.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227869 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-02 22:00:48 +00:00
Bruno Cardoso Lopes
12c944ba10 [X86][MMX] Cleanup shuffle, bitcast and insert element tests
- Merge MMX arg passing test files
- Merge MMX bitcast, insert elt and shuffle tests

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227867 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-02 21:56:11 +00:00
Tom Stellard
d73d1062fe R600/SI: 64-bit and larger memory access must be at least 4-byte aligned
This is true for SI only. CI+ supports unaligned memory accesses,
but this requires driver support, so for now we disallow unaligned
accesses for all GCN targets.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227822 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-02 18:02:28 +00:00
Tom Stellard
80e70ee18e R600/SI: Merge two test files
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227821 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-02 18:02:23 +00:00
Ahmed Bougacha
0f1a21bcb8 [AArch64] Prefer DUP/MOV ("CPY") to INS for vector_extract.
This avoids a partial false dependency on the previous content of
the upper lanes of the destination vector register.

Differential Revision: http://reviews.llvm.org/D7307


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227820 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-02 17:55:57 +00:00