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

llvm-svn: 86085

llvm-svn: 85947

llvm-svn: 85827

the loop preheader. Add instructions which are already in the preheader block that
may be common expressions of those that are hoisted out. These does get a few more
instructions CSE'ed.

llvm-svn: 85799

unfolding loads for hoisting.  getOpcodeAfterMemoryUnfold returns the
opcode of the original operation without the load, not the load
itself, MachineLICM needs to know the operand index in order to get
the correct register class. Extend getOpcodeAfterMemoryUnfold to
return this information.

llvm-svn: 85622

llvm-svn: 85515

the new instructions and leave the old one in place.

llvm-svn: 85393

otherwise unhoistable instructions in order to allow the loads
to be hoisted.

llvm-svn: 85364

VISIBILITY_HIDDEN removal.

llvm-svn: 85043

Chris claims we should never have visibility_hidden inside any .cpp file but
that's still not true even after this commit.

llvm-svn: 85042

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

TargetInstrDesc::isRematerializable flag, so it isn't necessary to do
this check in its callers.

llvm-svn: 83671

llvm-svn: 83624

llvm-svn: 83622

implementations with a new MachineInstr::isInvariantLoad, which uses
MachineMemOperands and is target-independent. This brings MachineLICM
and other functionality to targets which previously lacked an
isInvariantLoad implementation.

llvm-svn: 83475

allocatable. Even if it doesn't appear to have any defs, it may latter
on after register allocation.

llvm-svn: 82834

llvm-svn: 82825

llvm-svn: 79754

llvm-svn: 78677

 - Some clients which used DOUT have moved to DEBUG. We are deprecating the
   "magic" DOUT behavior which avoided calling printing functions when the
   statement was disabled. In addition to being unnecessary magic, it had the
   downside of leaving code in -Asserts builds, and of hiding potentially
   unnecessary computations.

llvm-svn: 77019

llvm-svn: 65592

Machine LICM increases register pressure and it almost always increase code size. For now, disable it for optimizing for size.

llvm-svn: 63856

llvm-svn: 63854

llvm-svn: 63729

Don't bother hoisting out a "cheap" instruction if all of its uses are PHIs. LICM "cheap" instructions are not particularly beneficial to start with. This will just end up making the copies harder to coalesce.

llvm-svn: 63728

For now, only hoist re-materilizable instructions. LICM will increase register pressure. We want to avoid spilling more instructions if it's possible.

llvm-svn: 63725

loops, hoisting instructions all the way out in one step rather
than hoisting them one nest level at a time. Also, make a few
other code simplifications. This speeds up MachineLICM
by several fold.

llvm-svn: 62283

llvm-svn: 61715

several places. isTerminator() returns true for a superset
of cases, and includes things like FP_REG_KILL, which are
nither return or branch but aren't safe to move/remat/etc.

llvm-svn: 61373

llvm-svn: 61184

isReg, etc., from isRegister, etc.

llvm-svn: 57006

llvm-svn: 55779

llvm-svn: 55578

llvm-svn: 55074

hoisting out some "test" and "cmp" instructions. This was obvious badness.

llvm-svn: 54908

llvm-svn: 53166

several things that were neither in an anonymous namespace nor static
but not intended to be global.

llvm-svn: 51017

llvm-svn: 50990

possible for it to produce worse code than before.

The rest of this patch is code cleanup.

llvm-svn: 50987