Improve search for available spill slots in RA

Previously we always searched for two adjacent spill slots, even if
we only needed one. This small change fixes that.

Test: m test-art-host

Change-Id: I021d355e6602ffee687c8537a959232b1504dcf1

1 files changed, 9 insertions, 3 deletions

diff --git a/compiler/optimizing/register_allocator.cc b/compiler/optimizing/register_allocator.cc
index 9d99668484..1b33408b7e 100644
--- a/compiler/optimizing/register_allocator.cc
+++ b/compiler/optimizing/register_allocator.cc
@@ -1346,9 +1346,15 @@ void RegisterAllocator::AllocateSpillSlotFor(LiveInterval* interval) {
   // Find an available spill slot.
   size_t slot = 0;
   for (size_t e = spill_slots->size(); slot < e; ++slot) {
-    if ((*spill_slots)[slot] <= parent->GetStart()
-        && (slot == (e - 1) || (*spill_slots)[slot + 1] <= parent->GetStart())) {
-      break;
+    if ((*spill_slots)[slot] <= parent->GetStart()) {
+      if (!parent->NeedsTwoSpillSlots()) {
+        // One spill slot is sufficient.
+        break;
+      }
+      if (slot == e - 1 || (*spill_slots)[slot + 1] <= parent->GetStart()) {
+        // Two spill slots are available.
+        break;
+      }
     }
   }