instruction defines subregisters.

Any existing subreg indices on the original instruction are preserved or
composed with the new subreg index.

Also substitute multiple operands mentioning the original register by using the
new MachineInstr::substituteRegister() function. This is necessary because there
will soon be <imp-def> operands added to non read-modify-write partial
definitions. This instruction:

  %reg1234:foo = FLAP %reg1234<imp-def>

will reMaterialize(%reg3333, bar) like this:

  %reg3333:bar-foo = FLAP %reg333:bar<imp-def>

Finally, replace the TargetRegisterInfo pointer argument with a reference to
indicate that it cannot be NULL.

llvm-svn: 105358

llvm-svn: 100709

- Change MachineInstr::isIdenticalTo to take a new option that determines whether it should skip checking defs or at least virtual register defs. This subsumes part of the TargetInstrInfo::isIdentical functionality.
- Eliminate TargetInstrInfo::isIdentical and replace it with produceSameValue. In the default case, produceSameValue just checks whether two machine instructions are identical (except for virtual register defs). But targets may override it to check for unusual cases (e.g. ARM pic loads from constant pools).

llvm-svn: 97628

Some instructions refer to unique labels, and so cannot be trivially cloned
with CloneMachineInstr.

llvm-svn: 92873

Patch by Howard Hinnant!

llvm-svn: 90365

llvm-svn: 88899

- If destination is a physical register and it has a subreg index, use the
  sub-register instead.
This fixes PR5423.

llvm-svn: 88745

  except it doesn't care if the definitions' virtual registers differ. This is
  used by machine LICM and other MI passes to perform CSE.
- Teach Thumb2InstrInfo::isIdentical() to check two t2LDRpci_pic are identical.
  Since pc relative constantpool entries are always different, this requires it
  it check if the values can actually the same.

llvm-svn: 86328

stack slots and giving them different PseudoSourceValue's did not fix the
problem of post-alloc scheduling miscompiling llvm itself.
- Apply Dan's conservative workaround by assuming any non fixed stack slots can
alias other memory locations. This means a load from spill slot #1 cannot 
move above a store of spill slot #2. 
- Enable post-alloc scheduling for x86 at optimization leverl Default and above.

llvm-svn: 84424

llvm-svn: 84411

llvm-svn: 84321

necessarily fixed. Only those will negative frame indices are "fixed."

llvm-svn: 84315

bootstrap of FSF-style PPC, so there is some
reason to believe the original bug (which was
never analyzed) has been fixed, probably by
82266.

llvm-svn: 83871

is trivially rematerializable and integrate it into
TargetInstrInfo::isTriviallyReMaterializable. This way, all places that
need to know whether an instruction is rematerializable will get the
same answer.

This enables the useful parts of the aggressive-remat option by
default -- using AliasAnalysis to determine whether a memory location
is invariant, and removes the questionable parts -- rematting operations
with virtual register inputs that may not be live everywhere.

llvm-svn: 83687

 - Allocate MachineMemOperands and MachineMemOperand lists in MachineFunctions.
   This eliminates MachineInstr's std::list member and allows the data to be
   created by isel and live for the remainder of codegen, avoiding a lot of
   copying and unnecessary translation. This also shrinks MemSDNode.
 - Delete MemOperandSDNode. Introduce MachineSDNode which has dedicated
   fields for MachineMemOperands.
 - Change MemSDNode to have a MachineMemOperand member instead of its own
   fields with the same information. This introduces some redundancy, but
   it's more consistent with what MachineInstr will eventually want.
 - Ignore alignment when searching for redundant loads for CSE, but remember
   the greatest alignment.

Target-specific code which previously used MemOperandSDNodes with generic
SDNodes now use MemIntrinsicSDNodes, with opcodes in a designated range
so that the SelectionDAG framework knows that MachineMemOperand information
is available.

llvm-svn: 82794

the base pointer, without the offset. This matches MemSDNode's
new alignment behavior, and holds more interesting information.

llvm-svn: 82473

Let each target determines whether a machine instruction is dead. If true, that allows late codeine passes to delete it.

This is considered a workaround. The problem is some targets are not modeling side effects correctly. PPC is apparently one of those. This patch allows ppc llvm-gcc to bootstrap on Darwin. Once we find out which instruction definitions are wrong, we can remove the PPCInstrInfo workaround.

llvm-svn: 76703

Avoid remat'ing instructions whose def have sub-register indices for now. It's just really really hard to get all the cases right.

llvm-svn: 75900

llvm-svn: 75312

Remove TargetInstrInfo::CommuteChangesDestination and added findCommutedOpIndices which returns the operand indices which are swapped (when applicable). This allows for some code clean up and future enhancements.

llvm-svn: 75264

CommuteChangesDestination() should check if to-be-commuted instruction defines any register. Also teaches the default commuteInstruction() to commute instruction without definitions (e.g. X86::test / ARM::tsp).

llvm-svn: 74602

booleans. This gives a better indication of what the "addReg()" is
doing. Remembering what all of those booleans mean isn't easy, especially if you
aren't spending all of your time in that code.

I took Jakob's suggestion and made it illegal to pass in "true" for the
flag. This should hopefully prevent any unintended misuse of this (by reverting
to the old way of using addReg()).

llvm-svn: 71722

llvm-svn: 63599

parts, and add target-independent code to add/preserve
MachineMemOperands.

llvm-svn: 60488

isReg, etc., from isRegister, etc.

llvm-svn: 57006

isImmediate(), isRegister(), and friends, to avoid confusion
about having two different names with the same meaning. I'm
not attached to the longer names, and would be ok with
changing to the shorter names if others prefer it.

llvm-svn: 56189

llvm-svn: 56097

Convert uses of std::vector in TargetInstrInfo to SmallVector.  This change had to be propoagated down into all the targets and up into all clients of this API.

llvm-svn: 54802

MachineMemOperands. The pools are owned by MachineFunctions.

This drastically reduces the number of calls to malloc/free made
during the "Emit" phase of scheduling, as well as later phases
in CodeGen. Combined with other changes, this speeds up the
"instruction selection" phase of CodeGen by 10% in some cases.

llvm-svn: 53212

llvm-svn: 52308

Infrastructure for getting the machine code size of a function and an instruction. X86, PowerPC and ARM are implemented

llvm-svn: 49809

llvm-svn: 48995

machine instr will change its definition register.

llvm-svn: 47166

llvm-svn: 47058

llvm-svn: 47043

Make MachineInstr::getDesc return a reference instead
of a pointer, since it can never be null.

llvm-svn: 45695

over to using them, instead of diddling Flags directly.  Change the
various flags from const variables to enums.

llvm-svn: 45677

that it is cheap and efficient to get.

Move a variety of predicates from TargetInstrInfo into 
TargetInstrDescriptor, which makes it much easier to query a predicate
when you don't have TII around.  Now you can use MI->getDesc()->isBranch()
instead of going through TII, and this is much more efficient anyway. Not
all of the predicates have been moved over yet.

Update old code that used MI->getInstrDescriptor()->Flags to use the
new predicates in many places.

llvm-svn: 45674

a header file from libcodegen.  This violates a layering order: codegen
depends on target, not the other way around.  The fix to this is to 
split TII into two classes, TII and TargetInstrInfoImpl, which defines
stuff that depends on libcodegen.  It is defined in libcodegen, where 
the base is not.

llvm-svn: 45475

e.g. MO.isMBB() instead of MO.isMachineBasicBlock().  I don't plan on 
switching everything over, so new clients should just start using the 
shorter names.

Remove old long accessors, switching everything over to use the short
accessor: getMachineBasicBlock() -> getMBB(), 
getConstantPoolIndex() -> getIndex(), setMachineBasicBlock -> setMBB(), etc.

llvm-svn: 45464