[LLVMdev] Generating unusual instruction
Dongrui She
sarevokcc at gmail.com
Mon Jan 7 06:29:44 PST 2013
Hi,
Have you try to directly describe such patterns in tblgen file? Like this:
(brcond (i32 (cond_op RC:$rs, RC:$rt)), bb:$offset)
MIPS backend does that. I also do this in my own backend, and seem to be
working fine.
On Mon, Jan 7, 2013 at 11:55 AM, Vikram Singh <vsp1729 at gmail.com> wrote:
> I have seen that most of the targets do comparison and branching
> in two separate instructions e.g. 'cmpl' followed by 'br' in x86 or the
> like.
> LLVM IR is also in same manner.
>
> I want to implement comparison+branching in one instruction like
>
> beq r1, r2, .label #if r1==r2 then jump to .label
>
> How to merge two instruction into one.
>
> Regards
> Vikram Singh
>
>
>
> --
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--
Regards,
Dongrui
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