[LLVMdev] Mandatory duplicated incoming nodes on phis
clattner at apple.com
Wed Aug 27 20:26:45 PDT 2008
On Aug 27, 2008, at 3:37 AM, Gary Benson wrote:
> I noticed that if you create a switch with multiple cases going to
> the same destination, then if that destination contains phis you
> need to add the incoming value an equivalent number of times. The
> attached code seems wrong, but it compiles as correct, and removing
> the duplicated incoming node causes an error. Is this expected?
I agree that this is somewhat annoying, but it is required to maintain
the invariant that a phi node in a block has the same number of
entries as the block has predecessors.
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