Limit the search space in RAGreedy::tryEvict().
When tryEvict() is looking for a cheaper register in the allocation
order, skip the tail of too expensive registers when possible.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172281 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/AllocationOrder.h b/lib/CodeGen/AllocationOrder.h
index a5293f6..aed461a 100644
--- a/lib/CodeGen/AllocationOrder.h
+++ b/lib/CodeGen/AllocationOrder.h
@@ -39,6 +39,9 @@
const VirtRegMap &VRM,
const RegisterClassInfo &RegClassInfo);
+ /// Get the allocation order without reordered hints.
+ ArrayRef<MCPhysReg> getOrder() const { return Order; }
+
/// Return the next physical register in the allocation order, or 0.
/// It is safe to call next() again after it returned 0, it will keep
/// returning 0 until rewind() is called.
@@ -53,6 +56,18 @@
return 0;
}
+ /// As next(), but allow duplicates to be returned, and stop before the
+ /// Limit'th register in the RegisterClassInfo allocation order.
+ ///
+ /// This can produce more than Limit registers if there are hints.
+ unsigned nextWithDups(unsigned Limit) {
+ if (Pos < 0)
+ return Hints.end()[Pos++];
+ if (Pos < int(Limit))
+ return Order[Pos++];
+ return 0;
+ }
+
/// Start over from the beginning.
void rewind() { Pos = -int(Hints.size()); }