This case occurs many times in various benchmarks, especially when combined
with the previous patch.  This allows it to get stuff like:
  if (X == 4 || X == 3)
    if (X == 5 || X == 8)

and

switch (X) {
case 4: case 5: case 6:
  if (X == 4 || X == 5)

llvm-svn: 11797

merged.

llvm-svn: 11796

register mapping or a stack slot mapping.

llvm-svn: 11795

llvm-svn: 11794

llvm-svn: 11793

This turns code like this:
  if (X == 4 | X == 7)
and
  if (X != 4 & X != 7)
into switch instructions.

llvm-svn: 11792

  if (X == 4 || X == 7)
and
  if (X != 4 && X != 7)

into switch instructions.

llvm-svn: 11791

llvm-svn: 11790

llvm-svn: 11789

llvm-svn: 11788

llvm-svn: 11787

llvm-svn: 11786

remove our dependency on boost!  Thanks to Reid Spencer for making this possible!

llvm-svn: 11785

template.  Thanks go out to Reid Spencer for skillfully extracting this
from boost!

llvm-svn: 11784

llvm-svn: 11783

llvm-svn: 11782

llvm-svn: 11781

251 (providing a generic machine code rewriter/spiller).

llvm-svn: 11780

llvm-svn: 11779

llvm-svn: 11778

llvm-svn: 11777

llvm-svn: 11776

llvm-svn: 11775

llvm-svn: 11774

llvm-svn: 11773

llvm-svn: 11772

llvm-svn: 11771

llvm-svn: 11770

llvm-svn: 11769

Also, turn 'shr int %X, 1234' into 'shr int %X, 31'

llvm-svn: 11768

llvm-svn: 11767

llvm-svn: 11766

llvm-svn: 11765

llvm-svn: 11764

llvm-svn: 11763

llvm-svn: 11762

llvm-svn: 11761

llvm-svn: 11760

llvm-svn: 11759

llvm-svn: 11758