struct RCInfo {
unsigned Tag;
unsigned NumRegs;
+ bool ProperSubClass;
OwningArrayPtr<unsigned> Order;
- RCInfo() : Tag(0), NumRegs(0) {}
+ RCInfo() : Tag(0), NumRegs(0), ProperSubClass(false) {}
operator ArrayRef<unsigned>() const {
- return ArrayRef<unsigned>(Order.get(), NumRegs);
+ return makeArrayRef(Order.get(), NumRegs);
}
};
return get(RC);
}
+ /// isProperSubClass - Returns true if RC has a legal super-class with more
+ /// allocatable registers.
+ ///
+ /// Register classes like GR32_NOSP are not proper sub-classes because %esp
+ /// is not allocatable. Similarly, tGPR is not a proper sub-class in Thumb
+ /// mode because the GPR super-class is not legal.
+ bool isProperSubClass(const TargetRegisterClass *RC) const {
+ return get(RC).ProperSubClass;
+ }
+
/// getLastCalleeSavedAlias - Returns the last callee saved register that
/// overlaps PhysReg, or 0 if Reg doesn't overlap a CSR.
unsigned getLastCalleeSavedAlias(unsigned PhysReg) const {
return CalleeSaved[N-1];
return 0;
}
+
+ /// isReserved - Returns true when PhysReg is a reserved register.
+ ///
+ /// Reserved registers may belong to an allocatable register class, but the
+ /// target has explicitly requested that they are not used.
+ ///
+ bool isReserved(unsigned PhysReg) const {
+ return Reserved.test(PhysReg);
+ }
+
+ /// isAllocatable - Returns true when PhysReg belongs to an allocatable
+ /// register class and it hasn't been reserved.
+ ///
+ /// Allocatable registers may show up in the allocation order of some virtual
+ /// register, so a register allocator needs to track its liveness and
+ /// availability.
+ bool isAllocatable(unsigned PhysReg) const {
+ return TRI->isInAllocatableClass(PhysReg) && !isReserved(PhysReg);
+ }
};
} // end namespace llvm