[turbofan] Try to allocate preferred register after splitting range.

src/compiler/register-allocator.cc

Index: src/compiler/register-allocator.cc
diff --git a/src/compiler/register-allocator.cc b/src/compiler/register-allocator.cc
index 403c344aee09209934a6581f0d5695aee71aeffd..684b9764a9a4cb240f065395a7500920f37d8e45 100644
--- a/src/compiler/register-allocator.cc
+++ b/src/compiler/register-allocator.cc
@@ -3152,6 +3152,9 @@ bool LinearScanAllocator::TryAllocateFreeReg(
     AddToUnhandledSorted(tail);
   }
 
+  // Try to allocate preferred register once more.
+  if (TryAllocatePreferredReg(current, free_until_pos)) return true;

[Jarin, 2017/03/16 06:24:28]

Could this go into the then-branch above? (before line 3153)

[georgia.kouveli, 2017/03/16 14:07:32]

Done.

+
   // Register reg is available at the range start and is free until the range
   // end.
   DCHECK(pos >= current->End());