Commit Graph

93 Commits

Author SHA1 Message Date
Owen Anderson
f1a0090073 Enhance the FixedLengthDecoder to be able to generate plausible-looking decoders for ARM.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135524 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-19 21:06:00 +00:00
Benjamin Kramer
5196c12e9f Add a new field to MCOperandInfo that contains information about the type of the Operand.
- The actual values are from the MCOI::OperandType enum.
- Teach tblgen to read it from the instruction definition.
- This is a better implementation of the hacks in edis.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135197 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-14 21:47:18 +00:00
Owen Anderson
16884415db Add a target-indepedent entry to MCInstrDesc to describe the encoded size of an opcode. Switch ARM over to using that rather than its own special MCInstrDesc bits.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135106 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-13 23:22:26 +00:00
Jim Grosbach
86f9adb8be TableGen'erated MC lowering for simple pseudo-instructions.
This allows the (many) pseudo-instructions we have that map onto a single
real instruction to have their expansion during MC lowering handled
automatically instead of the current cumbersome manual expansion required.
These sorts of pseudos are common when an instruction is used in situations
that require different MachineInstr flags (isTerminator, isBranch, et. al.)
than the generic instruction description has. For example, using a move
to the PC to implement a branch.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@134704 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-08 17:36:35 +00:00
Evan Cheng
ebdeeab812 Eliminate asm parser's dependency on TargetMachine:
- Each target asm parser now creates its own MCSubtatgetInfo (if needed).
- Changed AssemblerPredicate to take subtarget features which tablegen uses
  to generate asm matcher subtarget feature queries. e.g.
  "ModeThumb,FeatureThumb2" is translated to
  "(Bits & ModeThumb) != 0 && (Bits & FeatureThumb2) != 0".


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@134678 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-08 01:53:10 +00:00
Jim Grosbach
806fcc040e Don't require pseudo-instructions to carry encoding information.
For now this is distinct from isCodeGenOnly, as code-gen-only
instructions can (and often do) still have encoding information
associated with them. Once we've migrated all of them over to true
pseudo-instructions that are lowered to real instructions prior to
the printer/emitter, we can remove isCodeGenOnly and just use isPseudo.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@134539 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-06 21:33:38 +00:00
Owen Anderson
bea6f615ee Add support for alternative register names, useful for instructions whose operands are logically equivalent to existing registers, but happen to be printed specially. For example, an instruciton that prints d0[0] instead of s0.
Patch by Jim Grosbach.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133940 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-27 21:06:21 +00:00
Jakob Stoklund Olesen
4ce25d5d69 Add a RegisterTuples class to Target.td and TableGen.
A RegisterTuples instance is used to synthesize super-registers by
zipping together lists of sub-registers. This is useful for generating
pseudo-registers representing register sequence constraints like 'two
consecutive GPRs', or 'an even-odd pair of floating point registers'.

The RegisterTuples def can be used in register set operations when
building register classes. That is the only way of accessing the
synthesized super-registers.

For example, the ARM QQ register class of pseudo-registers could have
been formed like this:

  // Form pairs Q0_Q1, Q2_Q3, ...
  def QQPairs : RegisterTuples<[qsub_0, qsub_1],
                               [(decimate QPR, 2),
                                (decimate (shl QPR, 1), 2)]>;

  def QQ : RegisterClass<..., (add QQPairs)>;

Similarly, pseudo-registers representing '3 consecutive D-regs with
wraparound' look like:

  // Form D0_D1_D2, D1_D2_D3, ..., D30_D31_D0, D31_D0_D1.
  def DSeqTriples : RegisterTuples<[dsub_0, dsub_1, dsub_2],
                                   [(rotl DPR, 0),
                                    (rotl DPR, 1),
                                    (rotl DPR, 2)]>;

TableGen automatically computes aliasing information for the synthesized
registers.

Register tuples are still somewhat experimental. We still need to see
how they interact with MC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133407 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-20 02:50:54 +00:00
Jakob Stoklund Olesen
54c47c1ce9 Remove MethodProtos/MethodBodies and allocation_order_begin/end.
Targets that need to change the default allocation order should use the
AltOrders mechanism instead. See the X86 and ARM targets for examples.

The allocation_order_begin() and allocation_order_end() methods have been
replaced with getRawAllocationOrder(), and there is further support
functions in RegisterClassInfo.

It is no longer possible to insert arbitrary code into generated
register classes. This is a feature.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133332 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-18 03:08:20 +00:00
Jakob Stoklund Olesen
b4c704877d Provide AltOrders for specifying alternative allocation orders.
A register class can define AltOrders and AltOrderSelect instead of
defining method protos and bodies. The AltOrders lists can be defined
with set operations, and TableGen can verify that the alternative
allocation orders only contain valid registers.

This is currently an opt-in feature, and it is still possible to
override allocation_order_begin/end. That will not be true for long.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133320 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-18 00:50:49 +00:00
Jakob Stoklund Olesen
f28987b76e Use set operations instead of plain lists to enumerate register classes.
This simplifies many of the target description files since it is common
for register classes to be related or contain sequences of numbered
registers.

I have verified that this doesn't change the files generated by TableGen
for ARM and X86. It alters the allocation order of MBlaze GPR and Mips
FGR32 registers, but I believe the change is benign.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133105 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-15 23:28:14 +00:00
Jakob Stoklund Olesen
f462e3fac7 Make it possible to have unallocatable register classes.
Some register classes are only used for instruction operand constraints.
They should never be used for virtual registers. Previously, those
register classes were given an empty allocation order, but now you can
say 'let isAllocatable=0' in the register class definition.

TableGen calculates if a register is part of any allocatable register
class, and makes that information available in TargetRegisterDesc::inAllocatableClass.

The goal here is to eliminate use cases for overriding allocation_order_*
methods.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132508 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-02 23:07:20 +00:00
Rafael Espindola
7a067cc6e0 Introduce the DwarfRegAlias class for declaring that two registers have the
same dwarf number. This will be used for creating a dwarf number to register
mapping.

The only case that needs this so far is the XMM/YMM registers that unfortunately
do have the same numbers.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132314 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-30 17:49:59 +00:00
Jakob Stoklund Olesen
69ba413057 Don't allow per-register spill size and alignment.
These values were not used for anything. Spill size and alignment is a property
of the register class, not the register.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129906 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-21 03:43:21 +00:00
Jakob Stoklund Olesen
6bfba2e5af Prefer cheap registers for busy live ranges.
On the x86-64 and thumb2 targets, some registers are more expensive to encode
than others in the same register class.

Add a CostPerUse field to the TableGen register description, and make it
available from TRI->getCostPerUse. This represents the cost of a REX prefix or a
32-bit instruction encoding required by choosing a high register.

Teach the greedy register allocator to prefer cheap registers for busy live
ranges (as indicated by spill weight).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129864 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-20 18:19:48 +00:00
Bill Wendling
eef965f04b Add an option to not print the alias of an instruction. It defaults to "print
the alias".


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129485 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-13 23:36:21 +00:00
Evan Cheng
0f040a258f - Add "Bitcast" target instruction property for instructions which perform
nothing more than a bitcast.
- Teach tablegen to automatically infer "Bitcast" property.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127667 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-15 05:09:26 +00:00
Owen Anderson
d8c87888a7 Add FixedLenDecoderEmitter, the skeleton of a new disassembler emitter for fixed-length instruction encodings.
A major part of its (eventual) goal is to support a much cleaner separation between disassembly callbacks
provided by the target and the disassembler emitter itself, i.e. not requiring hardcoding of knowledge in tblgen
like the existing disassembly emitters do.

The hope is that some day this will allow us to replace the existing non-Thumb ARM disassembler and remove
some of the hacks the old one introduced to tblgen.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125966 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-18 21:51:29 +00:00
Owen Anderson
e02db88816 Clean trailing whitespace.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125304 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-10 19:56:23 +00:00
Bruno Cardoso Lopes
e7a54520b3 Implement support for custom target specific asm parsing of operands.
Motivation: Improve the parsing of not usual (different from registers or
immediates) operand forms.

This commit implements only the generic support. The ARM specific modifications
will come next.

A table like the one below is autogenerated for every instruction
containing a 'ParserMethod' in its AsmOperandClass

static const OperandMatchEntry OperandMatchTable[20] = {
 /* Mnemonic, Operand List Mask, Operand Class, Features */
 { "cdp", 29 /* 0, 2, 3, 4 */, MCK_Coproc, Feature_IsThumb|Feature_HasV6 },
 { "cdp", 58 /* 1, 3, 4, 5 */, MCK_Coproc, Feature_IsARM },

A matcher function very similar (but lot more naive) to
MatchInstructionImpl scans the table. After the mnemonic match, the
features are checked and if the "to be parsed" operand index is
present in the mask, there's a real match. Then, a switch like the one
below dispatch the parsing to the custom method provided in
'ParseMethod':

 case MCK_Coproc:
   return TryParseCoprocessorOperandName(Operands);




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125030 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-07 19:38:32 +00:00
Daniel Dunbar
cf12067ae0 MC/AsmMatcher: Add support for custom conversion functions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124870 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-04 17:12:15 +00:00
Evan Cheng
c36b7069b4 Do not model all INLINEASM instructions as having unmodelled side effects.
Instead encode llvm IR level property "HasSideEffects" in an operand (shared
with IsAlignStack). Added MachineInstrs::hasUnmodeledSideEffects() to check
the operand when the instruction is an INLINEASM.

This allows memory instructions to be moved around INLINEASM instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123044 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-07 23:50:32 +00:00
Evan Cheng
30a343aeed DBG_VALUE does not have any side effects; it also makes no sense to mark it cheap as a copy.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123031 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-07 21:08:26 +00:00
Evan Cheng
c4af4638df Remove ARM isel hacks that fold large immediates into a pair of add, sub, and,
and xor. The 32-bit move immediates can be hoisted out of loops by machine
LICM but the isel hacks were preventing them.

Instead, let peephole optimization pass recognize registers that are defined by
immediates and the ARM target hook will fold the immediates in.

Other changes include 1) do not fold and / xor into cmp to isel TST / TEQ
instructions if there are multiple uses. This happens when the 'and' is live
out, machine sink would have sinked the computation and that ends up pessimizing
code. The peephole pass would recognize situations where the 'and' can be
toggled to define CPSR and eliminate the comparison anyway.

2) Move peephole pass to after machine LICM, sink, and CSE to avoid blocking
important optimizations.

rdar://8663787, rdar://8241368


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119548 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-17 20:13:28 +00:00
Chris Lattner
2ac190238e add fields to the .td files unconditionally, simplifying tblgen a bit.
Switch the ARM backend to use 'let' instead of 'set' with this change.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119120 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-15 05:19:05 +00:00
Chris Lattner
662e5a30e8 Reimplement BuildResultOperands to be in terms of the result instruction's
operand list instead of the operand list redundantly declared on the alias
or instruction.

With this change, we finally remove the ins/outs list on the alias.  Before:
  def : InstAlias<(outs GR16:$dst), (ins GR8 :$src),
                  "movsx $src, $dst",
                  (MOVSX16rr8W GR16:$dst, GR8:$src)>;
After:
  def : InstAlias<"movsx $src, $dst",
                  (MOVSX16rr8W GR16:$dst, GR8:$src)>;

This also makes the alias mechanism more general and powerful, which will
be exploited in subsequent patches.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118329 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-06 07:14:44 +00:00
Jim Grosbach
9a376a8003 Tweak to fix spelling and grammar in comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117985 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-02 00:13:15 +00:00
Chris Lattner
f780811456 eliminate the old InstFormatName which is always "AsmString",
simplify CodeGenInstruction. No functionality change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117891 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-01 02:15:23 +00:00
Chris Lattner
a33b93f7f1 sketch out the planned instruction alias mechanism, add some comments about
how the push/pop mnemonic aliases are wrong.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117857 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-31 18:43:46 +00:00
Chris Lattner
0f899c78e1 Resolve a terrible hack in tblgen: instead of hardcoding
"In32BitMode" and "In64BitMode" into tblgen, allow any
predicate that inherits from AssemblerPredicate.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117831 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-30 19:38:20 +00:00
Chris Lattner
693173feef Implement (and document!) support for MnemonicAlias's to have Requires
directives, allowing things like this:

def : MnemonicAlias<"pop", "popl">, Requires<[In32BitMode]>;
def : MnemonicAlias<"pop", "popq">, Requires<[In64BitMode]>;

Move the rest of the X86 MnemonicAliases over to the .td file.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117830 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-30 19:23:13 +00:00
Chris Lattner
674c1dcca2 implement (and document!) the first kind of MC assembler alias, which
just remaps one mnemonic to another.  Convert a few of the X86 aliases
from .cpp to .td code.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117815 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-30 17:36:36 +00:00
Jim Grosbach
cf000c130f 80 columns.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117784 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-30 13:46:39 +00:00
Jim Grosbach
ca96a86165 Let a target specify whether it wants an assembly printer to be the MC version
or not. TableGen needs to generate the printInstruction() function as taking
an MCInstr* or a MachineInstr*, depending. Default to the old non-MC
version so that everything not yet using MC continues to just work without
fidding.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115126 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-30 01:29:54 +00:00
Owen Anderson
f523e476c2 Revert r114703 and r114702, removing the isConditionalMove flag from instructions. After further
reflection, this isn't going to achieve the purpose I intended it for.  Back to the drawing board!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114710 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-23 23:45:25 +00:00
Owen Anderson
5716180b1a Add an TargetInstrDesc bit to indicate that a given instruction is a conditional move.
Not intended functionality change, as nothing uses this yet.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114702 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-23 22:44:10 +00:00
Daniel Dunbar
4f98f83459 tblgen/AsmMatcher: Always emit the match function as 'MatchInstructionImpl',
target specific parsers can adapt the TargetAsmParser to this.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110888 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-12 00:55:32 +00:00
Bill Wendling
73739d0bf1 Add back in r109901, which adds a Compare flag to the target instructions. It's
useful after all.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110531 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-08 01:49:35 +00:00
Bill Wendling
5b55ff0c15 Revert r109901. The implementation of <rdar://problem/7405933> (r110423) doesn't
need the Compare flag after all.

--- Reverse-merging r109901 into '.':
U    include/llvm/Target/TargetInstrDesc.h
U    include/llvm/Target/Target.td
U    utils/TableGen/InstrInfoEmitter.cpp
U    utils/TableGen/CodeGenInstruction.cpp
U    utils/TableGen/CodeGenInstruction.h



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110424 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-06 01:36:09 +00:00
Bill Wendling
1844b1a5a4 Add a "Compare" flag to the target instruction descriptor. This will be used
later to identify and possibly remove superfluous compare instructions -- those
that are testing for and setting a status flag that should already be set.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@109901 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-30 22:48:39 +00:00
Bill Wendling
7431beaba2 Rename DBG_LABEL PROLOG_LABEL, because it's only used during prolog emission and
thus is a much more meaningful name.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108563 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-16 22:20:36 +00:00
Jakob Stoklund Olesen
a4e1ba53dd Add a new target independent COPY instruction and code to lower it.
The COPY instruction is intended to replace the target specific copy
instructions for virtual registers as well as the EXTRACT_SUBREG and
INSERT_SUBREG instructions in MachineFunctions. It won't we used in a selection
DAG.

COPY is lowered to native register copies by LowerSubregs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107529 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-02 22:29:50 +00:00
Jakob Stoklund Olesen
65766ce7df Clean up TargetOpcodes.h a bit, and limit the number of places where the full
list of predefined instructions appear. Add some consistency checks.

Ideally, TargetOpcodes.h should be produced by TableGen from Target.td, but it
is hardly worth the effort.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107520 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-02 21:44:22 +00:00
Eric Christopher
1f4a1493fb Remove isTwoAddress from llvm.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106470 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-21 20:35:09 +00:00
Bruno Cardoso Lopes
99405df044 Reapply r105521, this time appending "LLU" to 64 bit
immediates to avoid breaking the build.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@105652 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-08 22:51:23 +00:00
Chris Lattner
1087f54ddb revert r105521, which is breaking the buildbots with stuff like this:
In file included from X86InstrInfo.cpp:16:
X86GenInstrInfo.inc:2789: error: integer constant is too large for 'long' type
X86GenInstrInfo.inc:2790: error: integer constant is too large for 'long' type
X86GenInstrInfo.inc:2792: error: integer constant is too large for 'long' type
X86GenInstrInfo.inc:2793: error: integer constant is too large for 'long' type
X86GenInstrInfo.inc:2808: error: integer constant is too large for 'long' type
X86GenInstrInfo.inc:2809: error: integer constant is too large for 'long' type
X86GenInstrInfo.inc:2816: error: integer constant is too large for 'long' type
X86GenInstrInfo.inc:2817: error: integer constant is too large for 'long' type



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@105524 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-05 04:17:30 +00:00
Bruno Cardoso Lopes
3eca98bb3a Initial AVX support for some instructions. No patterns matched
yet, only assembly encoding support.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@105521 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-05 03:53:24 +00:00
Jakob Stoklund Olesen
ca561ffcf3 Replace the SubRegSet tablegen class with a less error-prone mechanism.
A Register with subregisters must also provide SubRegIndices for adressing the
subregisters. TableGen automatically inherits indices for sub-subregisters to
minimize typing.

CompositeIndices may be specified for the weirder cases such as the XMM sub_sd
index that returns the same register, and ARM NEON Q registers where both D
subregs have ssub_0 and ssub_1 sub-subregs.

It is now required that all subregisters are named by an index, and a future
patch will also require inherited subregisters to be named. This is necessary to
allow composite subregister indices to be reduced to a single index.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104704 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-26 17:27:12 +00:00
Jakob Stoklund Olesen
b555609e73 Revert "Replace the SubRegSet tablegen class with a less error-prone mechanism."
This reverts commit 104654.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104660 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-26 01:21:14 +00:00
Jakob Stoklund Olesen
6a45d681e5 Replace the SubRegSet tablegen class with a less error-prone mechanism.
A Register with subregisters must also provide SubRegIndices for adressing the
subregisters. TableGen automatically inherits indices for sub-subregisters to
minimize typing.

CompositeIndices may be specified for the weirder cases such as the XMM sub_sd
index that returns the same register, and ARM NEON Q registers where both D
subregs have ssub_0 and ssub_1 sub-subregs.

It is now required that all subregisters are named by an index, and a future
patch will also require inherited subregisters to be named. This is necessary to
allow composite subregister indices to be reduced to a single index.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104654 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-26 00:28:19 +00:00