llvm-svn: 30890

llvm-svn: 30889

llvm-svn: 30888

of Regression/TableGen/MultiClass.td.

llvm-svn: 30887

llvm-svn: 30886

llvm-svn: 30885

llvm-svn: 30884

llvm-svn: 30883

llvm-svn: 30882

llvm-svn: 30881

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llvm-svn: 30878

llvm-svn: 30877

llvm-svn: 30876

when the dag combiner simplifies an and mask, notice this and allow those bits
to be missing from the zap mask.

This compiles Alpha/zapnot4.ll into:

        sll $16,3,$0
        zapnot $0,3,$0
        ret $31,($26),1

instead of:

        ldah $0,1($31)
        lda $0,-8($0)
        sll $16,3,$1
        and $1,$0,$0
        ret $31,($26),1

It would be *really* nice to replace the hunk of code in the
AlphaISelDAGToDAG.cpp file that matches (and (srl (x, C), c2) into
(SRL (ZAPNOTi)) with a similar pattern, but I've spent enough time poking
at alpha.  Make andrew will do this.

llvm-svn: 30875

llvm-svn: 30874

As a bonus, use the GOT node instead of the AlphaISD::GOT for internal stuff.

llvm-svn: 30873

llvm-svn: 30872

The dag/inst combiners often 'simplify' the masked value based on whether
or not the bits are live or known zero/one.  This is good and dandy, but
often causes special case patterns to fail, such as alpha's CMPBGE pattern,
which looks like "(set GPRC:$RC, (setuge (and GPRC:$RA, 255), (and GPRC:$RB, 255)))".
Here the pattern for (and X, 255) should match actual dags like (and X, 254) if
the dag combiner proved that the missing bits are already zero (one for 'or').

For CodeGen/Alpha/cmpbge.ll:test2 for example, this results in:

        sll $16,1,$0
        cmpbge $0,$17,$0
        ret $31,($26),1

instead of:

        sll $16,1,$0
        and $0,254,$0
        and $17,255,$1
        cmpule $1,$0,$0
        ret $31,($26),1

... and requires no target-specific code.

llvm-svn: 30871

the second has an and of 254 not 255.

llvm-svn: 30870

llvm-svn: 30869

identical, this is just a refactoring.

llvm-svn: 30868

llvm-svn: 30867

llvm-svn: 30866

llvm-svn: 30865

llvm-svn: 30864

Domagoj Babic, thanks!

llvm-svn: 30863

llvm-svn: 30862

llvm-svn: 30861

llvm-svn: 30860

llvm-svn: 30859

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llvm-svn: 30853

llvm-svn: 30852

See comment in CanBeFoldedBy() for detailed explanation.

llvm-svn: 30851