def CRRC : RegisterClass<"PPC", [i32], 32, (add CR0, CR1, CR5, CR6,
CR7, CR2, CR3, CR4)>;
-def CTRRC : RegisterClass<"PPC", [i32], 32, (add CTR)>;
-def CTRRC8 : RegisterClass<"PPC", [i64], 64, (add CTR8)>;
+// The CTR registers are not allocatable because they're used by the
+// decrement-and-branch instructions, and thus need to stay live across
+// multiple basic blocks.
+def CTRRC : RegisterClass<"PPC", [i32], 32, (add CTR)> {
+ let isAllocatable = 0;
+}
+def CTRRC8 : RegisterClass<"PPC", [i64], 64, (add CTR8)> {
+ let isAllocatable = 0;
+}
+
def VRSAVERC : RegisterClass<"PPC", [i32], 32, (add VRSAVE)>;
def CARRYRC : RegisterClass<"PPC", [i32], 32, (add CARRY)> {
let CopyCost = -1;