1 //===-- llvm/CallingConvLower.cpp - Calling Conventions -------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by Chris Lattner and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements the CCState class, used for lowering and implementing
11 // calling conventions.
13 //===----------------------------------------------------------------------===//
15 #include "llvm/CodeGen/CallingConvLower.h"
16 #include "llvm/Target/MRegisterInfo.h"
19 CCState::CCState(const MRegisterInfo &mri) : MRI(mri) {
23 UsedRegs.resize(MRI.getNumRegs());
27 /// MarkAllocated - Mark a register and all of its aliases as allocated.
28 void CCState::MarkAllocated(unsigned Reg) {
29 UsedRegs[Reg/32] |= 1 << (Reg&31);
31 if (const unsigned *RegAliases = MRI.getAliasSet(Reg))
32 for (; (Reg = *RegAliases); ++RegAliases)
33 UsedRegs[Reg/32] |= 1 << (Reg&31);