This REALLY should be lowered by the legalizer!

llvm-svn: 22941

llvm-svn: 22935

llvm-svn: 22889

llvm-svn: 22884

llvm-svn: 22877

llvm-svn: 22869

llvm-svn: 22866

Now for int foo() { return -1; } we generate:
_foo:
        li r3, -1
        blr

instead of
_foo:
        lis r2, -1
        ori r3, r2, 65535
        blr

llvm-svn: 22864

llvm-svn: 22857

llvm-svn: 22855

llvm-svn: 22854

llvm-svn: 22851

llvm-svn: 22850

llvm-svn: 22849

several of the PowerPC opcodes that come in both negated and non-negated
forms.

llvm-svn: 22845

incomplete, but it is a start.  It handles basic argument/retval stuff, immediates,
add and sub.

llvm-svn: 22836