Mask out reserved registers when constructing the set of allocatable regs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112828 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/TargetRegisterInfo.cpp b/lib/Target/TargetRegisterInfo.cpp
index 49bfad54136d3a039e1526e24a93edbbc1581a8a..cdbe51fbdd92d748f751a9e1944e1e520a87e7d5 100644 (file)
--- a/lib/Target/TargetRegisterInfo.cpp
+++ b/lib/Target/TargetRegisterInfo.cpp
@@ -80,6 +80,11 @@ BitVector TargetRegisterInfo::getAllocatableSet(const MachineFunction &MF,
   for (TargetRegisterInfo::regclass_iterator I = regclass_begin(),
          E = regclass_end(); I != E; ++I)
     getAllocatableSetForRC(MF, *I, Allocatable);
+
+  // Mask out the reserved registers
+  BitVector Reserved = getReservedRegs(MF);
+  Allocatable ^= Reserved & Allocatable;
+
   return Allocatable;
 }