Displaying 1 result from an estimated 1 matches for "strongphieilimin".
2009 Aug 20
0
[LLVMdev] A question about StrongPhiElimination
...live range of r2, r3, and r5 do not interference,
StrongPhiElimination decides, before InsertCopies(), to rename both r2
and r3 to r5 based onthe algorithm in [1]
During InsertCopies(), because 'r3' is live after Block 3 and this is
the typical case where 'lost-copy' could happen, StrongPhiEilimination
inserts a copy from r3 to a temp register r99 based on the algorithm
in [2]. Block 3 then becomes
Block 3
r3 = phi(r1, r4)
r99 = r3
r4 = ...
r3 = r4
if (...) goto Block 3
else (...) goto Block 4
The Insert-copy algorithm in [2] would normally rename r3 in Block 4
to r99. Bu...