Commit Graph

102 Commits

Author SHA1 Message Date
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
Ulrich Weigand 380bece7af [SystemZ] "Generic" vector assembler instructions shoud clobber CC
There are several vector instructions which may or may not set the
condition code register, depending on the value of an argument.

For codegen, we use two versions of the instruction, one that sets
CC and one that doesn't, which hard-code appropriate values of that
argument.  But we also have a "generic" version of the instruction
that is used for the assembler/disassembler.  These generic versions
should always be considered to clobber CC just to be safe.

llvm-svn: 349761
2018-12-20 14:24:17 +00:00
Jonas Paulsson ebb1605bf3 [SystemZ] Bugfix for MVCLoop CC clobbering.
MVCLoop clobbers CC (since it emits a compare/branch), but this was not
modelled.

Review: Ulrich Weigand
llvm-svn: 331627
2018-05-07 10:48:43 +00:00
Ulrich Weigand b32f3656d2 [SystemZ] Do not use glue to represent condition code dependencies
Currently, an instruction setting the condition code is linked to
the instruction using the condition code via a "glue" link in the
SelectionDAG.  This has a number of drawbacks; in particular, it
means the same CC cannot be used by multiple users.  It also makes
it more difficult to efficiently implement SADDO et. al.

This patch changes the back-end to represent CC dependencies as
normal values during SelectionDAG matching, along the lines of
how this is handled in the X86 back-end already.

In addition to the core mechanics of updating all relevant patterns,
this requires a number of additional changes:

- We now need to be able to spill/restore a CC value into a GPR
  if necessary.  This means providing a copyPhysReg implementation
  for moves involving CC, and defining getCrossCopyRegClass.

- Since we still prefer to avoid such spills, we provide an override
  for IsProfitableToFold to avoid creating a merged LOAD / ICMP if
  this would result in multiple users of the CC.

- combineCCMask no longer requires a single CC user, and no longer
  need to be careful about preventing invalid glue/chain cycles.

- emitSelect needs to be more careful in marking CC live-in to
  the basic block it generates.  Also, we can now optimize the
  case of multiple subsequent selects with the same condition
  just like X86 does.

llvm-svn: 331202
2018-04-30 17:52:32 +00:00
Ulrich Weigand 79e5cd2fc5 [SystemZ] Refactor some VT casts in DAG match patterns
In patterns where we need to specify a result VT, prefer

  [(set (tr.vt tr.op:$V1), (operator ...))]

over

  [(set tr.op:$V1, (tr.vt (operator ...)))]

This is NFC now, but simplifies some future changes.

llvm-svn: 331192
2018-04-30 15:52:28 +00:00
Ulrich Weigand fb56686cd3 [SystemZ] Improve handling of Select pseudo-instructions
If we have LOCR instructions, select them directly from SelectionDAG
instead of first going through a pseudo instruction and then using
the custom inserter to emit the LOCR.

Provide Select pseudo-instructions for VR32/VR64 if we have vector
instructions, to avoid having to go through the first 16 FPRs
unnecessarily.

If we do not have LOCFHR, prefer using LOCR followed by a move
over a conditional branch.

llvm-svn: 331191
2018-04-30 15:49:27 +00:00
Jonas Paulsson 9a485985cd [SystemZ] Remove scheduling info from some Pseudo instructions (NFC).
If the MachineInstr uses a custom inserter and is then erased after
instruction selection, there is no use for mapping it to a sched class.

Review: Ulrich Weigand
llvm-svn: 331040
2018-04-27 14:09:03 +00:00
Jonas Paulsson b5b91cd402 [SystemZ] set 'guessInstructionProperties = 0' and set flags as needed.
This has proven a healthy exercise, as many cases of incorrect instruction
flags were corrected in the process. As part of this, IntrWriteMem was added
to several SystemZ instrinsics.

Furthermore, a bug was exposed in TwoAddress with this change (as incorrect
hasSideEffects flags were removed and instructions could now be sunk), and
the test case for that bugfix (r319646) is included here as
test/CodeGen/SystemZ/twoaddr-sink.ll.

One temporary test regression (one extra copy) which will hopefully go away
in upcoming patches for similar cases:
test/CodeGen/SystemZ/vec-trunc-to-i1.ll

Review: Ulrich Weigand.
https://reviews.llvm.org/D40437

llvm-svn: 319756
2017-12-05 11:24:39 +00:00
Ulrich Weigand f2968d58cb [SystemZ] Add support for IBM z14 processor (3/3)
This adds support for the new 128-bit vector float instructions of z14.
Note that these instructions actually only operate on the f128 type,
since only each 128-bit vector register can hold only one 128-bit
float value.  However, this is still preferable to the legacy 128-bit
float instructions, since those operate on pairs of floating-point
registers (so we can hold at most 8 values in registers), while the
new instructions use single vector registers (so we hold up to 32
value in registers).

Adding support includes:
- Enabling the instructions for the assembler/disassembler.
- CodeGen for the instructions.  This includes allocating the f128
  type now to the VR128BitRegClass instead of FP128BitRegClass.
- Scheduler description support for the instructions.

Note that for a small number of operations, we have no new vector
instructions (like integer <-> 128-bit float conversions), and so
we use the legacy instruction and then reformat the operand
(i.e. copy between a pair of floating-point registers and a
vector register).

llvm-svn: 308196
2017-07-17 17:44:20 +00:00
Ulrich Weigand 2b3482fe85 [SystemZ] Add support for IBM z14 processor (1/3)
This patch series adds support for the IBM z14 processor.  This part includes:
- Basic support for the new processor and its features.
- Support for new instructions (except vector 32-bit float and 128-bit float).
- CodeGen for new instructions, including new LLVM intrinsics.
- Scheduler description for the new processor.
- Detection of z14 as host processor.

Support for the new 32-bit vector float and 128-bit vector float
instructions is provided by separate patches.

llvm-svn: 308194
2017-07-17 17:41:11 +00:00
Ulrich Weigand 03ab2e2b1c [SystemZ] Add all remaining instructions
This adds all remaining instructions that were still missing, mostly
privileged and semi-privileged system-level instructions.  These are
provided for use with the assembler and disassembler only.

This brings the LLVM assembler / disassembler to parity with the
GNU binutils tools.

llvm-svn: 306876
2017-06-30 20:43:40 +00:00
Ulrich Weigand 3f484e68cc [SystemZ] Add decimal floating-point instructions
This adds assembler / disassembler support for the decimal
floating-point instructions.  Since LLVM does not yet have
support for decimal float types, these cannot be used for
codegen at this point.

llvm-svn: 304203
2017-05-30 10:15:16 +00:00
Ulrich Weigand f32adf6944 [SystemZ] Add hexadecimal floating-point instructions
This adds assembler / disassembler support for the hexadecimal
floating-point instructions.  Since the Linux ABI does not use
any hex float data types, these are not useful for codegen.

llvm-svn: 304202
2017-05-30 10:13:23 +00:00
Ulrich Weigand 93b369ed11 [SystemZ] Add miscellaneous instructions
This adds a few missing instructions for the assembler and
disassembler.  Those should be the last missing general-
purpose (Chapter 7) instructions for the z10 ISA.

llvm-svn: 302667
2017-05-10 14:20:15 +00:00
Ulrich Weigand d3604dc72c [SystemZ] Add missing arithmetic instructions
This adds the remaining general arithmetic instructions
for assembler / disassembler use.  Most of these are not
useful for codegen; a few might be, and those are listed
in the README.txt for future improvements.

llvm-svn: 302665
2017-05-10 14:18:47 +00:00
Ulrich Weigand c7eb5a95b2 [SystemZ] Add decimal integer instructions
This adds the set of decimal integer (BCD) instructions for
assembler / disassembler use.

llvm-svn: 302646
2017-05-10 12:42:45 +00:00
Ulrich Weigand 33a441adf9 [SystemZ] Add crypto instructions
This adds the set of message-security assist instructions for
assembler / disassembler use.

llvm-svn: 302645
2017-05-10 12:42:00 +00:00
Ulrich Weigand 435cd1a3e4 [SystemZ] Add translate/convert instructions
This adds the set of character-set translate and convert instructions
for assembler / disassembler use.

llvm-svn: 302644
2017-05-10 12:41:12 +00:00
Ulrich Weigand eb17909536 [SystemZ] Add missing memory/string instructions
This adds a number of missing memory and string instructions
for assembler / disassembler use.

llvm-svn: 302643
2017-05-10 12:40:15 +00:00
Ulrich Weigand 612d24badf [SystemZ] Support remaining atomic instructions
Add assembler support for all atomic instructions that weren't already
supported.  Some of those could be used to implement codegen for 128-bit
atomic operations, but this isn't done here yet.

llvm-svn: 288526
2016-12-02 18:24:16 +00:00
Ulrich Weigand 1c5a5c42de [SystemZ] Support floating-point control register instructions
Add assembler support for instructions manipulating the FPC.

Also add codegen support via the GCC compatibility builtins:
  __builtin_s390_sfpc
  __builtin_s390_efpc

llvm-svn: 288525
2016-12-02 18:21:53 +00:00
Ulrich Weigand da951d3bdc [SystemZ] Refactor hasSideEffects setting
Move setting of hasSideEffects out of SystemZInstrFormats.td,
to allow use of the format classes for instructions where this
flag shouldn't be set.  NFC.

llvm-svn: 288524
2016-12-02 18:19:22 +00:00
Ulrich Weigand 84404f30b3 [SystemZ] Support execution hint instructions
This adds assembler support for the instructions provided by the
execution-hint facility (NIAI and BP(R)P).  This required adding
support for the new relocation types for 12-bit and 24-bit PC-
relative offsets used by the BP(R)P instructions.

llvm-svn: 288031
2016-11-28 14:01:51 +00:00
Ulrich Weigand 758399131a [SystemZ] Add remaining branch instructions
This patch adds assembler support for the remaining branch instructions:
the non-relative branch on count variants, and all variants of branch
on index.

The only one of those that can be readily exploited for code generation
is BRCTH (branch on count using a high 32-bit register as count).  Do
use it, however, it is necessary to also introduce a hew CHIMux pseudo
to allow comparisons of a 32-bit value agains a short immediate to go
into a high register as well (implemented via CHI/CIH).

This causes a bit of codegen changes overall, but those have proven to
be neutral (or even beneficial) in performance measurements.

llvm-svn: 288029
2016-11-28 13:40:08 +00:00
Ulrich Weigand 524f276c74 [SystemZ] Improve use of conditional instructions
This patch moves formation of LOC-type instructions from (late)
IfConversion to the early if-conversion pass, and in some cases
additionally creates them directly from select instructions
during DAG instruction selection.

To make early if-conversion work, the patch implements the
canInsertSelect / insertSelect callbacks.  It also implements
the commuteInstructionImpl and FoldImmediate callbacks to
enable generation of the full range of LOC instructions.

Finally, the patch adds support for all instructions of the
load-store-on-condition-2 facility, which allows using LOC
instructions also for high registers.

Due to the use of the GRX32 register class to enable high registers,
we now also have to handle the cases where there are still no single
hardware instructions (conditional move from a low register to a high
register or vice versa).  These are converted back to a branch sequence
after register allocation.  Since the expandRAPseudos callback is not
allowed to create new basic blocks, this requires a simple new pass,
modelled after the ARM/AArch64 ExpandPseudos pass.

Overall, this patch causes significantly more LOC-type instructions
to be used, and results in a measurable performance improvement.

llvm-svn: 288028
2016-11-28 13:34:08 +00:00
Ulrich Weigand a0e7325023 [SystemZ] Support CL(G)T instructions
This adds support for the compare logical and trap (memory)
instructions that were added as part of the miscellaneous
instruction extensions feature with zEC12.

llvm-svn: 286587
2016-11-11 12:48:26 +00:00
Ulrich Weigand 4006e09d1d [SystemZ] Add program mask and addressing mode instructions
Add several instructions that operate on the program mask
or the addressing mode.  These are not really needed for
code generation under Linux, but are provided for completeness
for the assembler/disassembler.

llvm-svn: 286284
2016-11-08 20:17:02 +00:00
Ulrich Weigand 3d07d45089 [SystemZ] Always use semantic instruction classes
Define a couple of additional semantic classes and use them
throughout the .td files to make them more consistent and
more easily readable.

No functional change.

llvm-svn: 286268
2016-11-08 18:37:48 +00:00
Ulrich Weigand bfcfa0e207 [SystemZ] Refactor InstRR* instruction format patterns
This changes the InstRR (and related) patterns to no longer
automatically add an "r" at the end of the mnemonic.  This
makes the .td files more obviously understandable, and also
allows using the patterns for those few instructions that
do not follow the *r scheme.

Also add some more sub-formats of the RRF format class, to
match operand names and sequence from the PoP better.

No functional change.

llvm-svn: 286267
2016-11-08 18:36:31 +00:00
Ulrich Weigand 37bd451a55 [SystemZ] Rename some Inst* instruction format classes
Now that we've added instruction format subclasses like
InstRIb, it makes sense to rename the old InstRI to InstRIa.

Similar for InstRX, InstRXY, InstRS, InstRSY, and InstSS.

No functional change.

llvm-svn: 286266
2016-11-08 18:32:50 +00:00
Ulrich Weigand d2148caffc [SystemZ] Refactor branch and conditional instruction patterns
Rework patterns for branches, call & return instructions,
compare-and-branch, compare-and-trap, and conditional move
instructions.

In particular, simplify creation of patterns for the extended
opcodes of instructions that take a CC mask.

Also, use semantical instruction classes for all the instructions
instead of open-coding them in SystemZInstrInfo.td.

Adds a couple of the basic branch instructions (that are unused
for codegen) for the assembler/disassembler.

llvm-svn: 286263
2016-11-08 18:30:50 +00:00
Ulrich Weigand ec5d779eb8 [SystemZ] Fix encoding of MVCK and .insn ss
LLVM currently treats the first operand of MVCK as if it were a
regular base+index+displacement address.  However, it is in fact
a base+displacement combined with a length register field.

While the two might look syntactically similar, there are two
semantic differences:
- %r0 is a valid length register, even though it cannot be used
  as an index register.
- In an expression with just a single register like 0(%rX), the
  register is treated as base with normal addresses, while it is
  treated as the length register (with an empty base) for MVCK.

Fixed by adding a new operand parser class BDRAddr and reworking
the assembler parser to distinguish between address + length
register operands and regular addresses.

llvm-svn: 285574
2016-10-31 14:21:36 +00:00
Ulrich Weigand 7bdb485e18 [SystemZ] Do not use LOC(G) for volatile loads
It is not safe to use LOAD ON CONDITION to implement access to a memory
location marked "volatile", since the architecture leaves it unspecified
whether or not an access happens if the condition is false.

The current code already appears to care about that:
  def LOC  : CondUnaryRSY<"loc",  0xEBF2, nonvolatile_load, GR32, 4>;

Unfortunately, that "nonvolatile_load" operator is simply ignored
by the CondUnaryRSY class, and there was no test to catch it.

llvm-svn: 285077
2016-10-25 15:39:15 +00:00
Jonas Paulsson 8010b631d5 [SystemZ] Post-RA scheduler implementation
Post-RA sched strategy and scheduling instruction annotations for z196, zEC12
and z13.

This scheduler optimizes decoder grouping and balances processor resources
(including side steering the FPd unit instructions).

The SystemZHazardRecognizer keeps track of the scheduling state, which can
be dumped with -debug-only=misched.

Reviers: Ulrich Weigand, Andrew Trick.
https://reviews.llvm.org/D17260

llvm-svn: 284704
2016-10-20 08:27:16 +00:00
Ulrich Weigand 6e31ab388a [SystemZ] Add missing vector instructions for the assembler
Most z13 vector instructions have a base form where the data type of
the operation (whether to consider the vector to be 16 bytes, 8
halfwords, 4 words, or 2 doublewords) is encoded into a mask field,
and then a set of extended mnemonics where the mask field is not
present but the data type is encoded into the mnemonic name.

Currently, LLVM only supports the type-specific forms (since those
are really the ones needed for code generation), but not the base
type-generic forms.

To complete the assembler support and make it fully compatible with
the GNU assembler, this commit adds assembler aliases for all the
base forms of the various vector instructions.

It also adds two more alias forms that are documented in the PoP:
VFPSO/VFPSODB/WFPSODB -- generic form of VFLCDB etc.
VNOT -- special variant of VNO

llvm-svn: 284586
2016-10-19 13:03:18 +00:00
Ulrich Weigand 556a90c00c [SystemZ] Add optional argument to some vector string instructions
The vfee[bhf], vfene[bhf], and vistr[bhf] assembler mnemonics are
documented in the Principles of Operation to have an optional last
operand to encode arbitrary values in a mask field.

This commit adds support for those optional operands, and cleans up
the patterns to generate vector string instruction as bit.  No change
to code generation intended.

llvm-svn: 284585
2016-10-19 12:57:46 +00:00
Zhan Jun Liau 4fbc3f4a37 [SystemZ] Add support for the .insn directive
Summary:
Add support for the .insn directive.

.insn is an s390 specific directive that allows encoding of an instruction
instead of using a mnemonic. The motivating case is some code in node.js that
requires support for the .insn directive.

Reviewers: koriakin, uweigand

Subscribers: koriakin, llvm-commits

Differential Revision: https://reviews.llvm.org/D21809

llvm-svn: 278012
2016-08-08 15:13:08 +00:00
Zhan Jun Liau 8d3f29759f [SystemZ] Add missing classes and instructions
Summary:
Add instruction formats E, RSI, SSd, SSE, and SSF.

Added BRXH, BRXLE, PR, MVCK, STRAG, and ECTG instructions to test out
those formats.

Reviewers: uweigand

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D23179

llvm-svn: 277822
2016-08-05 15:14:34 +00:00
Zhan Jun Liau def708a0f9 [SystemZ] Recognize Load On Condition Immediate (LOCHI/LOGHI) opportunities
Summary: Add support for the z13 instructions LOCHI and LOCGHI which
conditionally load immediate values.  Add target instruction info hooks so
that if conversion will allow predication of LHI/LGHI.

Author: RolandF

Reviewers: uweigand

Subscribers: zhanjunl

Commiting on behalf of Roland.

Differential Revision: http://reviews.llvm.org/D22117

llvm-svn: 275086
2016-07-11 18:45:03 +00:00
Zhan Jun Liau 3b4c3f4d51 [SystemZ] Add support for missing instructions
Summary:
Add support to allow clang integrated assembler to recognize some
missing instructions, for openssl.

Instructions are:
LM, LMH, LMY, STM, STMH, STMY, ICM, ICMH, ICMY, SLA, SLAK, TML, TMH, EX, EXRL.

Reviewers: uweigand

Subscribers: koriakin, llvm-commits

Differential Revision: http://reviews.llvm.org/D22050

llvm-svn: 274869
2016-07-08 16:18:40 +00:00
Marcin Koscielnicki 518cbc7cc3 [SystemZ] Add floating-point test data class instructions.
These are not used by CodeGen yet - ISD combiners creating the new node
will come in subsequent patches.

llvm-svn: 274108
2016-06-29 07:29:07 +00:00
Zhan Jun Liau ab42cbce98 [SystemZ] Support Compare and Traps
Support and generate Compare and Traps like CRT, CIT, etc.

Support Trap as legal DAG opcodes and generate "j .+2" for them by default.
Add support for Conditional Traps and use the If Converter to convert them into
the corresponding compare and trap opcodes.

Differential Revision: http://reviews.llvm.org/D21155

llvm-svn: 272419
2016-06-10 19:58:10 +00:00
Bryan Chan e656f61d1e [SystemZ] Fix register ordering for BinaryRRF instructions
Summary:
The ordering of registers in BinaryRRF instructions are wrong, and
affects the copysign instruction (CPSDR). This results in the wrong
magnitude and sign being set.

Author: zhanjunl

Reviewers: kbarton, uweigand

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D20308

llvm-svn: 269922
2016-05-18 13:24:57 +00:00
Ulrich Weigand 1bac911c58 [SystemZ] Add SVC instruction
This is going to be useful for inline assembly only.

Author: koriakin
Differential Revision: http://reviews.llvm.org/D18952

llvm-svn: 265943
2016-04-11 14:35:39 +00:00
Ulrich Weigand 99ac5045ab [SystemZ] Add compare-and-branch instructions to MC
This adds MC support for fused compare + indirect branch instructions,
ie. CRB, CGRB, CLRB, CLGRB, CIB, CGIB, CLIB, CLGIB. They aren't actually
generated yet -- this is preparation for their use for conditional
returns in the next iteration of D17339.

Author: koriakin
Differential Revision: http://reviews.llvm.org/D18742

llvm-svn: 265296
2016-04-04 14:26:43 +00:00
Jonas Paulsson 45d5c673ec [SystemZ] Make the CCRegs regclass non-allocatable.
This was discovered to be necessary while running memchr-01.ll with
-verify-machinstrs, because it is not allowed to have a phys reg live
accross block boundaries while on SSA form, if the register is
allocatable (expect in entry block and landing pads).

In this test case, stringRRE pseudos are expanded after isel by adding
a loop block which produces a live out CC register. To make the test
pass, it was also necessary to not say that StringRRELoop pseudo uses
R0L, this is only true for the StringRRE opcode.

-verify-machineinstrs added to memchr-01.ll test.

New test case int-cmp-51.ll to test that MachineCSE can eliminate
an identical compare (which it couldn't do before).

Reviewed by Ulrich Weigand

llvm-svn: 251634
2015-10-29 16:13:55 +00:00
Ulrich Weigand 49506d78e7 [SystemZ] Add CodeGen support for scalar f64 ops in vector registers
The z13 vector facility includes some instructions that operate only on the
high f64 in a v2f64, effectively extending the FP register set from 16
to 32 registers.  It's still better to use the old instructions if the
operands happen to fit though, since the older instructions have a shorter
encoding.

Based on a patch by Richard Sandiford.

llvm-svn: 236524
2015-05-05 19:28:34 +00:00
Ulrich Weigand 80b3af7ab3 [SystemZ] Add CodeGen support for v4f32
The architecture doesn't really have any native v4f32 operations except
v4f32->v2f64 and v2f64->v4f32 conversions, with only half of the v4f32
elements being used.  Even so, using vector registers for <4 x float>
and scalarising individual operations is much better than generating
completely scalar code, since there's much less register pressure.
It's also more efficient to do v4f32 comparisons by extending to 2
v2f64s, comparing those, then packing the result.

This particularly helps with llvmpipe.

Based on a patch by Richard Sandiford.

llvm-svn: 236523
2015-05-05 19:27:45 +00:00
Ulrich Weigand ce4c109585 [SystemZ] Add CodeGen support for integer vector types
This the first of a series of patches to add CodeGen support exploiting
the instructions of the z13 vector facility.  This patch adds support
for the native integer vector types (v16i8, v8i16, v4i32, v2i64).

When the vector facility is present, we default to the new vector ABI.
This is characterized by two major differences:
- Vector types are passed/returned in vector registers
  (except for unnamed arguments of a variable-argument list function).
- Vector types are at most 8-byte aligned.

The reason for the choice of 8-byte vector alignment is that the hardware
is able to efficiently load vectors at 8-byte alignment, and the ABI only
guarantees 8-byte alignment of the stack pointer, so requiring any higher
alignment for vectors would require dynamic stack re-alignment code.

However, for compatibility with old code that may use vector types, when
*not* using the vector facility, the old alignment rules (vector types
are naturally aligned) remain in use.

These alignment rules are not only implemented at the C language level
(implemented in clang), but also at the LLVM IR level.  This is done
by selecting a different DataLayout string depending on whether the
vector ABI is in effect or not.

Based on a patch by Richard Sandiford.

llvm-svn: 236521
2015-05-05 19:25:42 +00:00
Ulrich Weigand a8b04e1cbc [SystemZ] Add z13 vector facility and MC support
This patch adds support for the z13 processor type and its vector facility,
and adds MC support for all new instructions provided by that facilily.

Apart from defining the new instructions, the main changes are:

- Adding VR128, VR64 and VR32 register classes.
- Making FP64 a subclass of VR64 and FP32 a subclass of VR32.
- Adding a D(V,B) addressing mode for scatter/gather operations
- Adding 1-, 2-, and 3-bit immediate operands for some 4-bit fields.
  Until now all immediate operands have been the same width as the
  underlying field (hence the assert->return change in decode[SU]ImmOperand).

In addition, sys::getHostCPUName is extended to detect running natively
on a z13 machine.

Based on a patch by Richard Sandiford.

llvm-svn: 236520
2015-05-05 19:23:40 +00:00