diff options
| -rw-r--r-- | include/llvm/Target/TargetRegisterInfo.h | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/include/llvm/Target/TargetRegisterInfo.h b/include/llvm/Target/TargetRegisterInfo.h index 81dec3e5b7..c97f172a1e 100644 --- a/include/llvm/Target/TargetRegisterInfo.h +++ b/include/llvm/Target/TargetRegisterInfo.h @@ -227,9 +227,12 @@ public: /// cheaper to allocate caller saved registers. /// /// These methods take a MachineFunction argument, which can be used to tune - /// the allocatable registers based on the characteristics of the function. - /// One simple example is that the frame pointer register can be used if - /// frame-pointer-elimination is performed. + /// the allocatable registers based on the characteristics of the function, + /// subtarget, or other criteria. + /// + /// Register allocators should account for the fact that an allocation + /// order iterator may return a reserved register and always check + /// if the register is allocatable (getAllocatableSet()) before using it. /// /// By default, these methods return all registers in the class. /// |