On Sat, 2005-12-31 at 02:12 -0500, Andrew Pinski wrote: > I noticed that we add a constraint for each variable that is assigned > to the > return value of a function call even though that information is useless > for > non pointers? > Is there a reason why we do this?
Laziness. > -------------------------------------------------------- > > It seems like we are spending extra time to try to figure out the > constraints Quantify "extra time". > on these variables than what we should be doing. The amount of time processing these constraints is basically nothing. They get processed during build_constraint_graph, and that's it. > > The reason for this processing is the following code in > tree-ssa-structalias.c: > /* Only care about operations with pointers, structures > containing pointers, dereferences, and call expressions. > */ > if (POINTER_TYPE_P (TREE_TYPE (lhsop)) > || AGGREGATE_TYPE_P (TREE_TYPE (lhsop)) > || TREE_CODE (rhsop) == CALL_EXPR) > > Or I am missing that a constraint that can happen? In IPA mode, for example, you still need to process the function call, regardless of what the return value is.
