Diego Novillo wrote:
On 2/29/08 7:04 PM, Steven Bosscher wrote:
I am not sure what would happen if GCC would start using FUD chains.
Is it like in SSA that every register is assigned only once?
But this would only affect the UD chains built by the DF code.
Yes, that's what I meant by "no subscripts" (see also my other message
re. birthpoints). Instead of subscripting variables you have multiple
defs for each variable. End each def is obviously assigned only once,
and each use in the IL stream except for phis has only one reaching def.
You do not necessarily need to think of subscripts, though they are a
clean notation for singleton UD chains.
Paolo
