502 Commits

Author SHA1 Message Date
Duncan P. N. Exon Smith
83902832de Revert "Revert "DI: Fold constant arguments into a single MDString""
This reverts commit r218918, effectively reapplying r218914 after fixing
an Ocaml bindings test and an Asan crash.  The root cause of the latter
was a tightened-up check in `DILexicalBlock::Verify()`, so I'll file a
PR to investigate who requires the loose check (and why).

Original commit message follows.

--

This patch addresses the first stage of PR17891 by folding constant
arguments together into a single MDString.  Integers are stringified and
a `\0` character is used as a separator.

Part of PR17891.

Note: I've attached my testcases upgrade scripts to the PR.  If I've
just broken your out-of-tree testcases, they might help.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219010 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-03 20:01:09 +00:00
Duncan P. N. Exon Smith
32e192aeb3 Revert "DI: Fold constant arguments into a single MDString"
This reverts commit r218914 while I investigate some bots.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218918 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-02 22:15:31 +00:00
Duncan P. N. Exon Smith
0917b70630 DI: Fold constant arguments into a single MDString
This patch addresses the first stage of PR17891 by folding constant
arguments together into a single MDString.  Integers are stringified and
a `\0` character is used as a separator.

Part of PR17891.

Note: I've attached my testcases upgrade scripts to the PR.  If I've
just broken your out-of-tree testcases, they might help.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218914 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-02 21:56:57 +00:00
Adrian Prantl
02474a32eb Move the complex address expression out of DIVariable and into an extra
argument of the llvm.dbg.declare/llvm.dbg.value intrinsics.

Previously, DIVariable was a variable-length field that has an optional
reference to a Metadata array consisting of a variable number of
complex address expressions. In the case of OpPiece expressions this is
wasting a lot of storage in IR, because when an aggregate type is, e.g.,
SROA'd into all of its n individual members, the IR will contain n copies
of the DIVariable, all alike, only differing in the complex address
reference at the end.

By making the complex address into an extra argument of the
dbg.value/dbg.declare intrinsics, all of the pieces can reference the
same variable and the complex address expressions can be uniqued across
the CU, too.
Down the road, this will allow us to move other flags, such as
"indirection" out of the DIVariable, too.

The new intrinsics look like this:
declare void @llvm.dbg.declare(metadata %storage, metadata %var, metadata %expr)
declare void @llvm.dbg.value(metadata %storage, i64 %offset, metadata %var, metadata %expr)

This patch adds a new LLVM-local tag to DIExpressions, so we can detect
and pretty-print DIExpression metadata nodes.

What this patch doesn't do:

This patch does not touch the "Indirect" field in DIVariable; but moving
that into the expression would be a natural next step.

http://reviews.llvm.org/D4919
rdar://problem/17994491

Thanks to dblaikie and dexonsmith for reviewing this patch!

Note: I accidentally committed a bogus older version of this patch previously.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218787 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-01 18:55:02 +00:00
Adrian Prantl
10c4265675 Revert r218778 while investigating buldbot breakage.
"Move the complex address expression out of DIVariable and into an extra"

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218782 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-01 18:10:54 +00:00
Adrian Prantl
076fd5dfc1 Move the complex address expression out of DIVariable and into an extra
argument of the llvm.dbg.declare/llvm.dbg.value intrinsics.

Previously, DIVariable was a variable-length field that has an optional
reference to a Metadata array consisting of a variable number of
complex address expressions. In the case of OpPiece expressions this is
wasting a lot of storage in IR, because when an aggregate type is, e.g.,
SROA'd into all of its n individual members, the IR will contain n copies
of the DIVariable, all alike, only differing in the complex address
reference at the end.

By making the complex address into an extra argument of the
dbg.value/dbg.declare intrinsics, all of the pieces can reference the
same variable and the complex address expressions can be uniqued across
the CU, too.
Down the road, this will allow us to move other flags, such as
"indirection" out of the DIVariable, too.

The new intrinsics look like this:
declare void @llvm.dbg.declare(metadata %storage, metadata %var, metadata %expr)
declare void @llvm.dbg.value(metadata %storage, i64 %offset, metadata %var, metadata %expr)

This patch adds a new LLVM-local tag to DIExpressions, so we can detect
and pretty-print DIExpression metadata nodes.

What this patch doesn't do:

This patch does not touch the "Indirect" field in DIVariable; but moving
that into the expression would be a natural next step.

http://reviews.llvm.org/D4919
rdar://problem/17994491

Thanks to dblaikie and dexonsmith for reviewing this patch!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218778 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-01 17:55:39 +00:00
Jingyue Wu
ccd995ab0c Revert r216862 due to a performance regression
Reported by Alexey Volkov in PR21115


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218771 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-01 15:22:13 +00:00
Asiri Rathnayake
e9bbacd0a8 Add missing natual vector cast.
Summary: The natual vector cast node (similar to bitcast) AArch64ISD::NVCAST
was introduced in r217159 and r217138. This patch adds a missing cast from
v2f32 to v1i64 which is causing some compilation failures. Also added test
cases to cover various modimm types and BUILD_VECTORs with i64 elements.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218751 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-01 09:59:45 +00:00
Juergen Ributzka
9952c922c2 Recommit r218010 [FastISel][AArch64] Fold bit test and branch into TBZ and TBNZ.
Note: This version fixed an issue with the TBZ/TBNZ instructions that were
generated in FastISel. The issue was that the 64bit version of TBZ (TBZX)
automagically sets the upper bit of the immediate field that is used to specify
the bit we want to test. To test for any of the lower 32bits we have to first
extract the subregister and use the 32bit version of the TBZ instruction (TBZW).

Original commit message:
Teach selectBranch to fold bit test and branch into a single instruction (TBZ or
TBNZ).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218693 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-30 19:59:35 +00:00
Juergen Ributzka
a0af4b0271 [FastISel][AArch64] Fold sign-/zero-extends into the load instruction.
The sign-/zero-extension of the loaded value can be performed by the memory
instruction for free. If the result of the load has only one use and the use is
a sign-/zero-extend, then we emit the proper load instruction. The extend is
only a register copy and will be optimized away later on.

Other instructions that consume the sign-/zero-extended value are also made
aware of this fact, so they don't fold the extend too.

This fixes rdar://problem/18495928.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218653 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-30 00:49:58 +00:00
James Molloy
aada52189e [AArch64] Redundant store instructions should be removed as dead code
If there is a store followed by a store with the same value to the same location, then the store is dead/noop. It can be removed.

This problem is found in spec2006-197.parser.

For example,
  stur    w10, [x11, #-4]
  stur    w10, [x11, #-4]
Then one of the two stur instructions can be removed.

Patch by David Xu!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218569 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-27 17:02:54 +00:00
David Xu
abf5bf221f Revert patch of r218493, delete the test case
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218495 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 02:40:54 +00:00
David Xu
c41ae2a5c4 Redundant store instructions should be removed as dead code
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218493 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 02:02:09 +00:00
Juergen Ributzka
af989653e0 [FastISel][AArch64] Also allow folding of sign-/zero-extend and shift-left for booleans (i1).
Shift-left immediate with sign-/zero-extensions also works for boolean values.
Update the assert and the test cases to reflect that fact.

This should fix a bug found by Chad.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218275 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-22 21:08:53 +00:00
Juergen Ributzka
faf93a6e0c [FastIsel][AArch64] Fix a think-o in address computation.
When looking through sign/zero-extensions the code would always assume there is
such an extension instruction and use the wrong operand for the address.

There was also a minor issue in the handling of 'AND' instructions. I
accidentially used a 'cast' instead of a 'dyn_cast'.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218161 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-19 22:23:46 +00:00
Jiangning Liu
61519cd699 Optimize sext/zext insertion algorithm in back-end.
With this optimization, we will not always insert zext for values crossing
basic blocks, but insert sext if the users of a value crossing basic block
has preference of sign predicate.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218101 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-19 05:30:35 +00:00
Juergen Ributzka
f789dac2dd Revert "[FastISel][AArch64] Fold bit test and branch into TBZ and TBNZ."
Reverting it until I have time to investigate a regression.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218035 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-18 08:07:40 +00:00
Juergen Ributzka
ef48b51126 Fix previous commit: [FastISel][AArch64] Simplify XALU multiplies.
When folding the intrinsic flag into the branch or select we also have to
consider the fact if the intrinsic got simplified, because it changes the
flag we have to check for.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218034 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-18 07:26:26 +00:00
Juergen Ributzka
e7fba004ce [FastISel][AArch64] Simplify XALU multiplies.
Simplify {s|u}mul.with.overflow to {s|u}add.with.overflow when possible.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218033 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-18 07:04:54 +00:00
Juergen Ributzka
4b6f00ad18 [FastISel][AArch64] Followup commit for 218031 to handle negative offsets too.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218032 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-18 07:04:49 +00:00
Juergen Ributzka
22b557d942 [FastISel][AArch64] Try to fold the offset into the add instruction when simplifying a memory address.
Small optimization in 'simplifyAddress'. When the offset cannot be encoded in
the load/store instruction, then we need to materialize the address manually.
The add instruction can encode a wider range of immediates than the load/store
instructions. This change tries to fold the offset into the add instruction
first before materializing the offset in a register.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218031 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-18 05:40:47 +00:00
Juergen Ributzka
ffbd4879eb [FastISel][AArch64] Fold 'AND' instruction during the address computation.
The 'AND' instruction could be used to mask out the lower 32 bits of a register.
If this is done inside an address computation we might be able to fold the
instruction into the memory instruction itself.

and  x1, x1, #0xffffffff   ---> ldrb x0, [x0, w1, uxtw]
ldrb x0, [x0, x1]

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218030 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-18 05:40:41 +00:00
Juergen Ributzka
710fc316fb [FastISel][AArch64] Fold bit test and branch into TBZ and TBNZ.
Teach selectBranch to fold bit test and branch into a single instruction (TBZ or
TBNZ).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218010 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-18 02:44:13 +00:00
Juergen Ributzka
7516444a26 [FastISel][AArch64] Custom lower sdiv by power-of-2.
Emit an optimized instruction sequence for sdiv by power-of-2 depending on the
exact flag.

This fixes rdar://problem/18224511.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217986 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-17 21:55:55 +00:00
Juergen Ributzka
580875d39d [FastISel][AArch64] Simplify mul to shift when possible.
This is related to rdar://problem/18369687.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217980 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-17 20:35:41 +00:00
Juergen Ributzka
46d6fd2908 [FastISel][AArch64] Fold mul into add/sub and logical operations.
Try to fold the multiply into the add/sub or logical operations (when
possible).

This is related to rdar://problem/18369687.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217978 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-17 19:51:38 +00:00
Juergen Ributzka
5461af97bc [FastISel][AArch64] Fold mul into the address computation of memory operations.
Teach 'computeAddress' to also fold multiplies into the address computation
(when possible).

This fixes rdar://problem/18369443.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217977 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-17 19:19:31 +00:00
Juergen Ributzka
07c9ae576c [FastISel][AArch64] Fold compare with zero and branch into CBZ and CBNZ.
This takes advanatage of the CBZ and CBNZ instruction to further optimize the
common null check pattern into a single instruction.

This is related to rdar://problem/18358882.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217972 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-17 18:05:34 +00:00
Juergen Ributzka
17e0ee5078 [FastISel][AArch64] Improve branch selection to support all FP conditions.
This adds the last two missing floating-point condition codes (FCMP_UEQ and
FCMP_ONE) also to the branch selection. In these two cases an additonal branch
instruction is required.

This also adds unit tests to checks all the different condition codes.

This is related o rdar://problem/18358882.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217966 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-17 17:46:47 +00:00
Juergen Ributzka
c9bc145e31 [FastISel][AArch64] Add vector support to argument lowering.
Lower the first 8 vector arguments too.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217850 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-16 00:25:30 +00:00
Juergen Ributzka
c0f00e90d2 [FastISel][AArch64] Add missing test case for previous commit.
This adds the missing test case for the previous commit:
Allow handling of vectors during return lowering for little endian machines.

Sorry for the noise.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217847 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-15 23:47:57 +00:00
Juergen Ributzka
df445d7af2 [FastISel][AArch64] Lower sin/cos/pow to runtime lib calls.
Also lower sin/cos/pow to runtime lib calls.

This fixes rdar://problem/18343468.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217839 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-15 22:33:06 +00:00
Juergen Ributzka
323445f706 [FastISel][AArch64] Add lowering support for frem.
This lowers frem to a runtime libcall inside fast-isel.

The test case also checks the CallLoweringInfo bug that was exposed by this
change.

This fixes rdar://problem/18342783.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217833 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-15 22:07:49 +00:00
Juergen Ributzka
86bdc1efbe [FastISel][AArch64] Improve floating-point compare support.
Add support for the last two missing fcmp condition codes: UEQ and ONE.

This fixes rdar://problem/18341575.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217823 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-15 20:47:16 +00:00
Juergen Ributzka
5bf1f01c15 [FastISel][AArch64] Add support for non-native types for logical ops.
Extend the logical ops selection to also support non-native types such as i1,
i8, and i16.

Fixes rdar://problem/18330589.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217732 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-13 23:46:28 +00:00
Chad Rosier
4fb3a966d0 [AArch64] Enable post-RA MI scheduler.
Phabricator Revision: http://reviews.llvm.org/D5278
Patch by Sanjin Sijaric!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217693 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-12 17:40:39 +00:00
Matt Arsenault
31b1bdbd95 Add DAG combine for shl + add of constants.
Do
 (shl (add x, c1), c2) -> (add (shl x, c2), c1 << c2)

This is already done for multiplies, but since multiplies
by powers of two are turned into shifts, we also need
to handle it here.

This might want checks for isLegalAddImmediate to avoid
transforming an add of a legal immediate with one that isn't.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217610 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-11 17:34:19 +00:00
Arnaud A. de Grandmaison
d1c83953b9 [AArch64] Reenable the PBQP test now that the leak issue has been fixed.
David Blaikie's commits r217563 & r217564, which added shared_ptr to the
CostPool have fixed some memory leak issues exposed by the PBQP with
coalescing constraints.

The sanitizer bot was failing because of those leaks. Now that the leaks
are gone, we can reenable the aarch64/pbqp test.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217580 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-11 10:39:52 +00:00
David Xu
65aac0f8e3 Build correct vector filled with undef nodes
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217570 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-11 05:10:28 +00:00
Arnaud A. de Grandmaison
50196a89d1 [AArch64] Temporarily desactivate the PBQP test, while I investigate some leaks in the allocator
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217531 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-10 18:40:18 +00:00
Arnaud A. de Grandmaison
438669ca81 [AArch64] Add experimental PBQP support
This adds target specific support for using the PBQP register allocator on the
AArch64, for the A57 cpu.

By default, the PBQP allocator is not used, unless explicitely required
on the command line with "-aarch64-pbqp".

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217504 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-10 14:06:10 +00:00
Asiri Rathnayake
3babc141b2 [AArch 64] Use a constant pool load for weak symbol references when
using static relocation model and small code model.

Summary: currently we generate GOT based relocations for weak symbol
references regardless of the underlying relocation model. This should
be change so that in static relocation model we use a constant pool
load instead.

Patch from: Keith Walker

Reviewers: Renato Golin, Tim Northover

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217503 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-10 13:54:38 +00:00
Chad Rosier
b30d031de4 [AArch64] Improve AA to remove unneeded edges in the AA MI scheduling graph.
Patch by Sanjin Sijaric <ssijaric@codeaurora.org>!
Phabricator Review: http://reviews.llvm.org/D5103

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217371 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-08 14:43:48 +00:00
Jiangning Liu
b20b9bf9fd [AArch64] Add pass to enable additional comparison optimizations by CSE.
Patched by Sergey Dmitrouk.

This pass tries to make consecutive compares of values use same operands to
allow CSE pass to remove duplicated instructions. For this it analyzes
branches and adjusts comparisons with immediate values by converting:

GE -> GT
GT -> GE
LT -> LE
LE -> LT

and adjusting immediate values appropriately. It basically corrects two
immediate values towards each other to make them equal.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217220 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-05 02:55:24 +00:00
Tim Northover
8dcac5d77a AArch64: fix vector-immediate BIC/ORR on big-endian devices.
Follow up to r217138, extending the logic to other NEON-immediate instructions.
As before, the instruction already performs the correct operation and we're
just using a different type for convenience, so we want a true nop-cast.

Patch by Asiri Rathnayake.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217159 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-04 15:05:24 +00:00
Tim Northover
dfe4e3e706 AArch64: fix big-endian immediate materialisation
We were materialising big-endian constants using DAG nodes with types different
from what was requested, followed by a bitcast. This is fine on little-endian
machines where bitcasting is a nop, but we need a slightly different
representation for big-endian. This adds a new set of NVCAST (natural-vector
cast) operations which are always nops.

Patch by Asiri Rathnayake.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217138 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-04 09:46:14 +00:00
Juergen Ributzka
cd72c216cd Revert r216803 "[MachineSinking] Clear kill flag of all operands at all their uses."
This reverts commit r216803, because it might have broken the buildbot.
The issue is tracked in PR20842.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217120 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-04 02:07:36 +00:00
Juergen Ributzka
68a4ab08b3 [FastISel][AArch64] Add target-specific lowering for logical operations.
This change adds support for immediate and shift-left folding into logical
operations.

This fixes rdar://problem/18223183.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217118 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-04 01:29:18 +00:00
Juergen Ributzka
847547086d Reapply r216805 "[MachineCombiner][AArch64] Use the correct register class for MADD, SUB, and OR.""
This reapplies r216805 with a fix to a copy-past error, which resulted in an
incorrect register class.

Original commit message:
Select the correct register class for the various instructions that are
generated when combining instructions and constrain the registers to the
appropriate register class.

This fixes rdar://problem/18183707.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217019 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-03 07:07:10 +00:00
Juergen Ributzka
dd7a7107c1 [FastISel][AArch64] Add target-dependent instruction selection for Add/Sub.
There is already target-dependent instruction selection support for Adds/Subs to
support compares and the intrinsics with overflow check. This takes advantage of
the existing infrastructure to also support Add/Sub, which allows the folding of
immediates, sign-/zero-extends, and shifts.

This fixes rdar://problem/18207316.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217007 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-03 01:38:36 +00:00