[LLVMdev] LLVM commit 410f38e01597120b41e406ec1cea69127463f9e5

[deadal nix]

OK from what I understand, the DAG.getSExtOrTrunc(SetCC, DL, SelectVT) is
unecessary and the SelectVT is nto the right type (as it is called with
incorrect parameter).

Here is a patch so it won't generate a loop. I ran make check and it
doesn't look like anything is broken.


2014-07-07 11:36 GMT-07:00 Matt Arsenault <arsenm2 at gmail.com>:

>
> On Jul 5, 2014, at 7:14 PM, deadal nix <deadalnix at gmail.com> wrote:
>
> > OK, so in you case, you want DAG.getSExtOrTrunc(SetCC, DL, SelectVT) to
> tunc the result from i64 to i32 on 64 bits targets, if I understand
> correctly.
> >
> > 2 questions:
> >  - Why not generating a selectcc node directly ? It avoid having to mess
> up with intermediate values.
> Well first, that's what it did originally and wasn't what I was changing.
> selectcc might not be legal, and I'm not sure why it even exists.  I don't
> see how it's any harder to match select + setcc vs. selectcc, and selectcc
> just gives you another case to worry about.
>
>
> >  - Why calling getSetCCResultType(VT) ? VT is not the type of a
> parameter of setcc, and this looks incorrect to me.
> That's what it did originally, and what I fixed. It now checks
> getSetCCResultType of the operand's operand's value type, the setcc's
> operand
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