Commit Graph

168 Commits

Author SHA1 Message Date
Rafael Espindola 82149a1aa9 Use shouldAssumeDSOLocal in classifyGlobalReference.
And teach shouldAssumeDSOLocal that ppc has no copy relocations.

The resulting code handle a few more case than before. For example, it
knows that a weak symbol can be resolved to another .o file, but it
will still be in the main executable.

llvm-svn: 293180
2017-01-26 15:02:31 +00:00
Hal Finkel a9321059b9 [PowerPC] Refactor soft-float support, and enable PPC64 soft float
This change enables soft-float for PowerPC64, and also makes soft-float disable
all vector instruction sets for both 32-bit and 64-bit modes. This latter part
is necessary because the PPC backend canonicalizes many Altivec vector types to
floating-point types, and so soft-float breaks scalarization support for many
operations. Both for embedded targets and for operating-system kernels desiring
soft-float support, it seems reasonable that disabling hardware floating-point
also disables vector instructions (embedded targets without hardware floating
point support are unlikely to have Altivec, etc. and operating system kernels
desiring not to use floating-point registers to lower syscall cost are unlikely
to want to use vector registers either). If someone needs this to work, we'll
need to change the fact that we promote many Altivec operations to act on
v4f32. To make it possible to disable Altivec when soft-float is enabled,
hardware floating-point support needs to be expressed as a positive feature,
like the others, and not a negative feature, because target features cannot
have dependencies on the disabling of some other feature. So +soft-float has
now become -hard-float.

Fixes PR26970.

llvm-svn: 283060
2016-10-02 02:10:20 +00:00
Hal Finkel b074a608ce [PowerPC] Add support for -mlongcall
The "long call" option forces the use of the indirect calling sequence for all
calls (even those that don't really need it). GCC provides this option; This is
helpful, under certain circumstances, for building very-large binaries, and
some other specialized use cases.

Fixes PR19098.

llvm-svn: 280040
2016-08-30 00:59:23 +00:00
Duncan P. N. Exon Smith 632987296f Target: Remove unused arguments from overrideSchedPolicy, NFC
TargetSubtargetInfo::overrideSchedPolicy takes two MachineInstr*
arguments (begin and end) that invite implicit conversions from
MachineInstrBundleIterator.  One option would be to change their type to
an iterator, but since they don't seem to have been used since the API
was added in 2010, I'm deleting the dead code.

llvm-svn: 274304
2016-07-01 00:23:27 +00:00
Rafael Espindola db6bd02185 Delete unused includes. NFC.
llvm-svn: 274225
2016-06-30 12:19:16 +00:00
Rafael Espindola 3beef8d6db Move shouldAssumeDSOLocal to Target.
Should fix the shared library build.

llvm-svn: 273958
2016-06-27 23:15:57 +00:00
Rafael Espindola 65787a9e01 Refactor to use shouldAssumeDSOLocal. NFC.
llvm-svn: 273612
2016-06-23 20:50:42 +00:00
Nemanja Ivanovic 6e29baf7f5 [Power9] Add support for -mcpu=pwr9 in the back end
This patch corresponds to review:
http://reviews.llvm.org/D19683

Simply adds the bits for being able to specify -mcpu=pwr9 to the back end.

llvm-svn: 268950
2016-05-09 18:54:58 +00:00
Nemanja Ivanovic a621a7f9c3 [PowerPC] Basic support for P9 atomic loads and stores
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
2016-03-31 15:26:37 +00:00
Hal Finkel fa7057a415 [PowerPC] Refactor popcnt[dw] target features
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
2016-03-29 01:36:01 +00:00
Hal Finkel 7059d41622 [PowerPC] On the A2, popcnt[dw] are very slow
The A2 cores support the popcntw/popcntd instructions, but they're microcoded,
and slower than our default software emulation. Specifically, popcnt[dw] take
approximately 74 cycles, whereas our software emulation takes only 24-28
cycles.

I've added a new target feature to indicate a slow popcnt[dw], instead of just
removing the existing target feature from the a2/a2q processor models, because:
  1. This allows us to return more accurate information via the TTI interface
     (I recognize that this currently makes no practical difference)
  2. Is hopefully easier to understand (it allows the core's features to match
     its manual while still having the desired effect).

llvm-svn: 264600
2016-03-28 17:52:08 +00:00
Nemanja Ivanovic 1a5706ca1b Fix for PR26180
Corresponds to Phabricator review:
http://reviews.llvm.org/D16592

This fix includes both an update to how we handle the "generic" CPU on LE
systems as well as Anton's fix for the Fast Isel issue.

llvm-svn: 262233
2016-02-29 16:42:27 +00:00
Kit Barton 93612ec5f2 Power9] Implement new vsx instructions: compare and conversion
This change implements the following vsx instructions:

Quad/Double-Precision Compare:
xscmpoqp xscmpuqp
xscmpexpdp xscmpexpqp
xscmpeqdp xscmpgedp xscmpgtdp xscmpnedp
xvcmpnedp(.) xvcmpnesp(.)
Quad-Precision Floating-Point Conversion
xscvqpdp(o) xscvdpqp
xscvqpsdz xscvqpswz xscvqpudz xscvqpuwz xscvsdqp xscvudqp
xscvdphp xscvhpdp xvcvhpsp xvcvsphp
xsrqpi xsrqpix xsrqpxp
28 instructions

Phabricator: http://reviews.llvm.org/D16709
llvm-svn: 262068
2016-02-26 21:11:55 +00:00
Nemanja Ivanovic b033f67df0 Define a feature for __float128 support in the PPC back end
This patch corresponds to review:
http://reviews.llvm.org/D15117

In preparation for supporting IEEE Quad precision floating point,
this patch simply defines a feature to specify the target supports this.
For now, nothing is done with the target feature, we just don't want
warnings from the Clang FE when a user specifies -mfloat128.
Calling convention and other related work will add to this patch in
the near future.

llvm-svn: 255642
2015-12-15 12:19:34 +00:00
Petar Jovanovic 280f7101e8 [Power PC] llvm soft float support for ppc32
This is the second in a set of patches for soft float support for ppc32,
it enables soft float operations.

Patch by Strahinja Petrovic.

Differential Revision: http://reviews.llvm.org/D13700

llvm-svn: 255516
2015-12-14 17:57:33 +00:00
Eric Christopher 25bf4a8617 Power8 and later support fusing addis/addi and addis/ld instruction
pairs that use the same register to execute as a single instruction.
No Functional Change

Patch by Kyle Butt!

llvm-svn: 253724
2015-11-20 22:38:20 +00:00
Eric Christopher c180836722 Weak non-function symbols were being accessed directly, which is
incorrect, as the chosen representative of the weak symbol may not live
with the code in question. Always indirect the access through the TOC
instead.

Patch by Kyle Butt!

llvm-svn: 253708
2015-11-20 20:51:31 +00:00
Daniel Sanders 50f17235dd Revert r247692: Replace Triple with a new TargetTuple in MCTargetDesc/* and related. NFC.
Eric has replied and has demanded the patch be reverted.

llvm-svn: 247702
2015-09-15 16:17:27 +00:00
Daniel Sanders 153010c52d Re-commit r247683: Replace Triple with a new TargetTuple in MCTargetDesc/* and related. NFC.
Summary:
This is the first patch in the series to migrate Triple's (which are ambiguous)
to TargetTuple's (which aren't).

For the moment, TargetTuple simply passes all requests to the Triple object it
holds. Once it has replaced Triple, it will start to implement the interface in
a more suitable way.

This change makes some changes to the public C++ API. In particular,
InitMCSubtargetInfo(), createMCRelocationInfo(), and createMCSymbolizer()
now take TargetTuples instead of Triples. The other public C++ API's have
been left as-is for the moment to reduce patch size.

This commit also contains a trivial patch to clang to account for the C++ API
change. Thanks go to Pavel Labath for fixing LLDB for me.

Reviewers: rengolin

Subscribers: jyknight, dschuff, arsenm, rampitec, danalbert, srhines, javed.absar, dsanders, echristo, emaste, jholewinski, tberghammer, ted, jfb, llvm-commits, rengolin

Differential Revision: http://reviews.llvm.org/D10969

llvm-svn: 247692
2015-09-15 14:08:28 +00:00
Daniel Sanders c40de48041 Revert r247684 - Replace Triple with a new TargetTuple ...
LLDB needs to be updated in the same commit.

llvm-svn: 247686
2015-09-15 13:46:21 +00:00
Daniel Sanders 18d4b0dab7 Replace Triple with a new TargetTuple in MCTargetDesc/* and related. NFC.
Summary:
This is the first patch in the series to migrate Triple's (which are ambiguous)
to TargetTuple's (which aren't).

For the moment, TargetTuple simply passes all requests to the Triple object it
holds. Once it has replaced Triple, it will start to implement the interface in
a more suitable way.

This change makes some changes to the public C++ API. In particular,
InitMCSubtargetInfo(), createMCRelocationInfo(), and createMCSymbolizer()
now take TargetTuples instead of Triples. The other public C++ API's have
been left as-is for the moment to reduce patch size.

This commit also contains a trivial patch to clang to account for the C++ API
change.

Reviewers: rengolin

Subscribers: jyknight, dschuff, arsenm, rampitec, danalbert, srhines, javed.absar, dsanders, echristo, emaste, jholewinski, tberghammer, ted, jfb, llvm-commits, rengolin

Differential Revision: http://reviews.llvm.org/D10969

llvm-svn: 247683
2015-09-15 13:17:40 +00:00
Mehdi Amini 157e5a6d10 Remove getDataLayout() from TargetSelectionDAGInfo (had no users)
Summary:
Remove empty subclass in the process.

This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.

Reviewers: echristo

Subscribers: jholewinski, llvm-commits, rafael, yaron.keren, ted

Differential Revision: http://reviews.llvm.org/D11045

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 241780
2015-07-09 02:10:08 +00:00
Kit Barton 4f79f96fd7 Properly handle the mftb instruction.
The mftb instruction was incorrectly marked as deprecated in the PPC
Backend. Instead, it should not be treated as deprecated, but rather be
implemented using the mfspr instruction. A similar patch was put into GCC last
year. Details can be found at:

https://sourceware.org/ml/binutils/2014-11/msg00383.html.
This change will replace instances of the mftb instruction with the mfspr
instruction for all CPUs except 601 and pwr3. This will also be the default
behaviour.

Additional details can be found in:

https://llvm.org/bugs/show_bug.cgi?id=23680

Phabricator review: http://reviews.llvm.org/D10419

llvm-svn: 239827
2015-06-16 16:01:15 +00:00
Matthias Braun 39a2afc941 Rename TargetSubtargetInfo::enablePostMachineScheduler() to enablePostRAScheduler()
r213101 changed the behaviour of this method to not only affect the
PostMachineScheduler scheduler but also the PostRAScheduler scheduler,
renaming should make this fact clear. Also document that the preferred
way is to specify this in the scheduling model instead of overriding
this method.

Differential Revision: http://reviews.llvm.org/D10427

llvm-svn: 239659
2015-06-13 03:42:16 +00:00
Daniel Sanders a73f1fdb19 Replace string GNU Triples with llvm::Triple in MCSubtargetInfo and create*MCSubtargetInfo(). NFC.
Summary:
This continues the patch series to eliminate StringRef forms of GNU triples
from the internals of LLVM that began in r239036.

Reviewers: rafael

Reviewed By: rafael

Subscribers: rafael, ted, jfb, llvm-commits, rengolin, jholewinski

Differential Revision: http://reviews.llvm.org/D10311

llvm-svn: 239467
2015-06-10 12:11:26 +00:00
Nemanja Ivanovic c38b5311cb Add direct moves to/from VSR and exploit them for FP/INT conversions
This patch corresponds to review:
http://reviews.llvm.org/D8928

It adds direct move instructions to/from VSX registers to GPR's. These are
exploited for FP <-> INT conversions.

llvm-svn: 234682
2015-04-11 10:40:42 +00:00
Nemanja Ivanovic c09047916a Add LLVM support for remaining integer divide and permute instructions from ISA 2.06
This is the patch corresponding to review:
http://reviews.llvm.org/D8406

It adds some missing instructions from ISA 2.06 to the PPC back end.

llvm-svn: 234546
2015-04-09 23:54:37 +00:00
Ulrich Weigand 7aed6890fd [PowerPC] Remove TargetMachine CPU auto-detection
As was done for X86 in r206094.

llvm-svn: 233684
2015-03-31 12:01:06 +00:00
Kit Barton 535e69de34 Add Hardware Transactional Memory (HTM) Support
This patch adds Hardware Transaction Memory (HTM) support supported by ISA 2.07
(POWER8). The intrinsic support is based on GCC one [1], but currently only the
'PowerPC HTM Low Level Built-in Function' are implemented.

The HTM instructions follows the RC ones and the transaction initiation result
is set on RC0 (with exception of tcheck). Currently approach is to create a
register copy from CR0 to GPR and comapring. Although this is suboptimal, since
the branch could be taken directly by comparing the CR0 value, it generates code
correctly on both test and branch and just return value. A possible future
optimization could be elimitate the MFCR instruction to branch directly.

The HTM usage requires a recently newer kernel with PPC HTM enabled. Tested on
powerpc64 and powerpc64le.

This is send along a clang patch to enabled the builtins and option switch.

[1] https://gcc.gnu.org/onlinedocs/gcc/PowerPC-Hardware-Transactional-Memory-Built-in-Functions.html

Phabricator Review: http://reviews.llvm.org/D8247

llvm-svn: 233204
2015-03-25 19:36:23 +00:00
Nemanja Ivanovic 0adf26b9b0 Add support for part-word atomics for PPC
http://reviews.llvm.org/D8090#inline-67337

llvm-svn: 231843
2015-03-10 20:51:07 +00:00
Nemanja Ivanovic e8effe1edb Add LLVM support for PPC cryptography builtins
Review: http://reviews.llvm.org/D7955

llvm-svn: 231285
2015-03-04 20:44:33 +00:00
Hal Finkel c93a9a2cb4 [PowerPC] Add support for the QPX vector instruction set
This adds support for the QPX vector instruction set, which is used by the
enhanced A2 cores on the IBM BG/Q supercomputers. QPX vectors are 256 bytes
wide, holding 4 double-precision floating-point values. Boolean values, modeled
here as <4 x i1> are actually also represented as floating-point values
(essentially  { -1, 1 } for { false, true }). QPX shares many features with
Altivec and VSX, but is distinct from both of them. One major difference is
that, instead of adding completely-separate vector registers, QPX vector
registers are extensions of the scalar floating-point registers (lane 0 is the
corresponding scalar floating-point value). The operations supported on QPX
vectors mirrors that supported on the scalar floating-point values (with some
additional ones for permutations and logical/comparison operations).

I've been maintaining this support out-of-tree, as part of the bgclang project,
for several years. This is not the entire bgclang patch set, but is most of the
subset that can be cleanly integrated into LLVM proper at this time. Adding
this to the LLVM backend is part of my efforts to rebase bgclang to the current
LLVM trunk, but is independently useful (especially for codes that use LLVM as
a JIT in library form).

The assembler/disassembler test coverage is complete. The CodeGen test coverage
is not, but I've included some tests, and more will be added as follow-up work.

llvm-svn: 230413
2015-02-25 01:06:45 +00:00
Eric Christopher 75dc3904a5 Add a FIXME to move IsLittleEndian to the target machine.
llvm-svn: 229472
2015-02-17 06:45:17 +00:00
Eric Christopher fee6aaf683 Move ABI handling and 64-bitness to the PowerPC target machine.
This required changing how the computation of the ABI is handled
and how some of the checks for ABI/target are done.

llvm-svn: 229471
2015-02-17 06:45:15 +00:00
Eric Christopher a10d58dba8 Move the target machine variable so that it's initialized early
enough we can use it to initialize frame lowering.

llvm-svn: 229168
2015-02-13 22:48:51 +00:00
Eric Christopher e8dbfe1cf8 Stash the TargetMachine on the subtarget so we can access it later.
Clean up a subtarget function that has it passed in while we're at it.

llvm-svn: 229164
2015-02-13 22:23:04 +00:00
Bill Schmidt fe88b18990 [PowerPC] Implement the vpopcnt instructions for POWER8
Patch by Kit Barton.

Add the vector population count instructions for byte, halfword, word,
and doubleword sizes.  There are two major changes here:

    PPCISelLowering.cpp: Make CTPOP legal for vector types.
    PPCRegisterInfo.td: Added v2i64 to the VRRC register
      definition. This is needed for the doubleword variations of the
      integer ops that were added in P8. 

Test Plan

Test the instruction vpcnt* encoding/decoding in ppc64-encoding-vmx.s

Test the generation of the vpopcnt instructions for various vector
data types.  When adding the v2i64 type to the Vector Register set, I
also needed to add the appropriate bit conversion patterns between
v2i64 and the existing vector types.  Testing for these conversions
were also added in the test case by passing a different vector type as
a parameter into the test functions.  There is also a run step that
will ensure the vpopcnt instructions are generated when the vsx
feature is disabled.

llvm-svn: 228046
2015-02-03 21:58:23 +00:00
Eric Christopher cccae7951c Use the cached subtargets and remove calls to getSubtarget/getSubtargetImpl
without a Function argument.

llvm-svn: 227622
2015-01-30 22:02:31 +00:00
Bill Schmidt 8cf15ced8c [PowerPC] Complete setting the baseline for ppc64le
Patch by Nemanja Ivanovic.

As was uncovered by the failing test case (when run on non-PPC
platforms), the feature set when compiling with -march=ppc64le was not
being picked up. This change ensures that if the -mcpu option is not
specified, the correct feature set is picked up regardless of whether
we are on PPC or not.

llvm-svn: 227455
2015-01-29 15:59:09 +00:00
Eric Christopher 8b7706517c Move DataLayout back to the TargetMachine from TargetSubtargetInfo
derived classes.

Since global data alignment, layout, and mangling is often based on the
DataLayout, move it to the TargetMachine. This ensures that global
data is going to be layed out and mangled consistently if the subtarget
changes on a per function basis. Prior to this all targets(*) have
had subtarget dependent code moved out and onto the TargetMachine.

*One target hasn't been migrated as part of this change: R600. The
R600 port has, as a subtarget feature, the size of pointers and
this affects global data layout. I've currently hacked in a FIXME
to enable progress, but the port needs to be updated to either pass
the 64-bitness to the TargetMachine, or fix the DataLayout to
avoid subtarget dependent features.

llvm-svn: 227113
2015-01-26 19:03:15 +00:00
Hal Finkel e2ab0f17cf [PowerPC] Loosen ELFv1 PPC64 func descriptor loads for indirect calls
Function pointers under PPC64 ELFv1 (which is used on PPC64/Linux on the
POWER7, A2 and earlier cores) are really pointers to a function descriptor, a
structure with three pointers: the actual pointer to the code to which to jump,
the pointer to the TOC needed by the callee, and an environment pointer. We
used to chain these loads, and make them opaque to the rest of the optimizer,
so that they'd always occur directly before the call. This is not necessary,
and in fact, highly suboptimal on embedded cores. Once the function pointer is
known, the loads can be performed ahead of time; in fact, they can be hoisted
out of loops.

Now these function descriptors are almost always generated by the linker, and
thus the contents of the descriptors are invariant. As a result, by default,
we'll mark the associated loads as invariant (allowing them to be hoisted out
of loops). I've added a target feature to turn this off, however, just in case
someone needs that option (constructing an on-stack descriptor, casting it to a
function pointer, and then calling it cannot be well-defined C/C++ code, but I
can imagine some JIT-compilation system doing so).

Consider this simple test:
  $ cat call.c

  typedef void (*fp)();
  void bar(fp x) {
    for (int i = 0; i < 1600000000; ++i)
      x();
  }

  $ cat main.c

  typedef void (*fp)();
  void bar(fp x);
  void foo() {}
  int main() {
    bar(foo);
  }

On the PPC A2 (the BG/Q supercomputer), marking the function-descriptor loads
as invariant brings the execution time down to ~8 seconds from ~32 seconds with
the loads in the loop.

The difference on the POWER7 is smaller. Compiling with:

  gcc -std=c99 -O3 -mcpu=native call.c main.c : ~6 seconds [this is 4.8.2]

  clang -O3 -mcpu=native call.c main.c : ~5.3 seconds

  clang -O3 -mcpu=native call.c main.c -mno-invariant-function-descriptors : ~4 seconds
  (looks like we'd benefit from additional loop unrolling here, as a first
   guess, because this is faster with the extra loads)

The -mno-invariant-function-descriptors will be added to Clang shortly.

llvm-svn: 226207
2015-01-15 21:17:34 +00:00
Bill Schmidt 082cfc05f1 [PPC64] Add support for the ICBT instruction on POWER8.
Patch by Kit Barton.

Support for the ICBT instruction is currently present, but limited to
embedded processors. This change adds a new FeatureICBT that can be used
to identify whether the ICBT instruction is available on a specific processor.

Two new tests are added:
 * Positive test to ensure the icbt instruction is present when using
-mcpu=pwr8
 * Negative test to ensure the icbt instruction is not generated when
using -mcpu=pwr7

Both test cases use the Prefetch opcode in LLVM. They are based on the
ppc64-prefetch.ll test case.

llvm-svn: 226033
2015-01-14 20:17:10 +00:00
Hal Finkel 5ff00b4350 [PowerPC] Add a flag for experimenting with subreg liveness tracking
This cannot yet be enabled by default, it causes ~50 miscompiles in the test
suite.

llvm-svn: 225497
2015-01-09 02:03:11 +00:00
Hal Finkel 4edc66b8de [PowerPC] Add support for the CMPB instruction
Newer POWER cores, and the A2, support the cmpb instruction. This instruction
compares its operands, treating each of the 8 bytes in the GPRs separately,
returning a 'mask' result of 0 (for false) or -1 (for true) in each byte.

Code generation support is added, in the form of a PPCISelDAGToDAG
DAG-preprocessing routine, that recognizes patterns close to what the
instruction computes (either exactly, or related by a constant masking
operation), and generates the cmpb instruction (along with any necessary
constant masking operation). This can be expanded if use cases arise.

llvm-svn: 225106
2015-01-03 01:16:37 +00:00
Bill Schmidt efe9ce216e [PowerPC 4/4] Enable little-endian support for VSX.
With the foregoing three patches, VSX instructions can be used for
little endian.  This patch removes the restriction that prevented
this, and re-enables the test cases from the first three patches.

llvm-svn: 223792
2014-12-09 16:59:57 +00:00
Rafael Espindola 246c4fb5d9 Remove redundant calls to isMaterializable.
This removes calls to isMaterializable in the following cases:

* It was redundant with a call to isDeclaration now that isDeclaration returns
  the correct answer for materializable functions.
* It was followed by a call to Materialize. Just call Materialize and check EC.

llvm-svn: 221050
2014-11-01 16:46:18 +00:00
Bill Schmidt dcce023549 [PowerPC] Reduce names from Power8Vector to P8Vector
Per Hal Finkel's review, improving typability of some variable names.

llvm-svn: 219514
2014-10-10 17:21:15 +00:00
Bill Schmidt cfc4a54a48 [PowerPC] Add feature for Power8 vector extensions
The current VSX feature for PowerPC specifies availability of the VSX
instructions added with the 2.06 architecture version.  With 2.07, the
architecture adds new instructions to both the Category:Vector and
Category:VSX instruction sets.  Additionally, unaligned vector storage
operations have improved performance.

This patch adds a feature to provide access to the new instructions
and performance capabilities of Power8.  For compatibility with GCC,
the feature is controlled via a new -mpower8-vector switch, and the
feature causes the __POWER8_VECTOR__ builtin define to be generated by
the preprocessor.

There is a companion patch for cfe being committed at the same time.

llvm-svn: 219501
2014-10-10 15:09:28 +00:00
Hal Finkel fe3368cb57 [PowerPC] Modern Book-E cores support sync
Older Book-E cores, such as the PPC 440, support only msync (which has the same
encoding as sync 0), but not any of the other sync forms. Newer Book-E cores,
however, do support sync, and for performance reasons we should allow the use
of the more-general form.

This refactors msync use into its own feature group so that it applies by
default only to older Book-E cores (of the relevant cores, we only have
definitions for the PPC440/450 currently).

llvm-svn: 218923
2014-10-02 22:34:22 +00:00
Eric Christopher f6ed33e7fa constify the TargetMachine argument used in the subtarget and
lowering constructors.

llvm-svn: 218832
2014-10-01 21:36:28 +00:00