[LLVMdev] Branch-like intrinsic

Bill Wendling isanbard at gmail.com
Mon Apr 14 15:02:29 PDT 2008


On Mon, Apr 14, 2008 at 2:50 PM, Edward Lee <eslee3 at uiuc.edu> wrote:
> On Mon, Apr 14, 2008 at 5:37 PM, Chris Lattner <sabre at nondot.org> wrote:
>  >  The code generator does CFG simplification to handle cases where blocks
>  >  become dead during lowering.
>  Oh... is there a way to prevent that from happening? While %x is
>  always 1 and %T is always taken, %F isn't actually dead. There would
>  be a way (with another intrinsic) for control to flow into %F at the
>  point of..
>  br i1 %x, label %T, label %F
>
>  That's why I wanted the rest of the compiler to still know about the
>  potential flow into %F.
>
Then that flow would be explicit in the CFG, right? Then %F wouldn't
be dead, I'm assuming.

-bw



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