llvm dev - Jun 2011 - [LLVMdev] Doubt on phi nodes

Hi all,
I have a doubt on the usage of phi nodes in LLVM: if I define a value in 
a bb, are phi nodes needed in the blocks that are dominated by the bb 
where the value is defined?
As an example consider the following trivial example:
// BB0
A = 5;
if (condition) { // BB1
   B = 2;
} else { // BB2
   B = 1;
}
// BB3
is a phi node required for A in BB3?

b.r.,
Carlo Alberto Ferraris
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Hi Carlo,
> I have a doubt on the usage of phi nodes in LLVM: if I define a value in a
bb,
> are phi nodes needed in the blocks that are dominated by the bb where the
value
> is defined?
> As an example consider the following trivial example:
> // BB0
> A = 5;
> if (condition) { // BB1
> B = 2;
> } else { // BB2
> B = 1;
> }
> // BB3
> is a phi node required for A in BB3?
no, it is not required AFAIK.

Ciao, Duncan.