MachineRegisterInfo.cpp revision 1eb5cf9c7d0b0b04402eddc007b0de414488baf4
162ed6b9ade63bf01717ce5274fa11e93e873d245Chris Lattner//===-- lib/Codegen/MachineRegisterInfo.cpp -------------------------------===// 284bc5427d6883f73cfeae3da640acd011d35c006Chris Lattner// 384bc5427d6883f73cfeae3da640acd011d35c006Chris Lattner// The LLVM Compiler Infrastructure 484bc5427d6883f73cfeae3da640acd011d35c006Chris Lattner// 584bc5427d6883f73cfeae3da640acd011d35c006Chris Lattner// This file is distributed under the University of Illinois Open Source 684bc5427d6883f73cfeae3da640acd011d35c006Chris Lattner// License. See LICENSE.TXT for details. 784bc5427d6883f73cfeae3da640acd011d35c006Chris Lattner// 884bc5427d6883f73cfeae3da640acd011d35c006Chris Lattner//===----------------------------------------------------------------------===// 984bc5427d6883f73cfeae3da640acd011d35c006Chris Lattner// 1084bc5427d6883f73cfeae3da640acd011d35c006Chris Lattner// Implementation of the MachineRegisterInfo class. 1184bc5427d6883f73cfeae3da640acd011d35c006Chris Lattner// 1284bc5427d6883f73cfeae3da640acd011d35c006Chris Lattner//===----------------------------------------------------------------------===// 1384bc5427d6883f73cfeae3da640acd011d35c006Chris Lattner 1484bc5427d6883f73cfeae3da640acd011d35c006Chris Lattner#include "llvm/CodeGen/MachineRegisterInfo.h" 1584bc5427d6883f73cfeae3da640acd011d35c006Chris Lattnerusing namespace llvm; 1684bc5427d6883f73cfeae3da640acd011d35c006Chris Lattner 176f0d024a534af18d9e60b3ea757376cd8a3a980eDan GohmanMachineRegisterInfo::MachineRegisterInfo(const TargetRegisterInfo &TRI) { 1884bc5427d6883f73cfeae3da640acd011d35c006Chris Lattner VRegInfo.reserve(256); 196f0d024a534af18d9e60b3ea757376cd8a3a980eDan Gohman UsedPhysRegs.resize(TRI.getNumRegs()); 2062ed6b9ade63bf01717ce5274fa11e93e873d245Chris Lattner 2162ed6b9ade63bf01717ce5274fa11e93e873d245Chris Lattner // Create the physreg use/def lists. 226f0d024a534af18d9e60b3ea757376cd8a3a980eDan Gohman PhysRegUseDefLists = new MachineOperand*[TRI.getNumRegs()]; 236f0d024a534af18d9e60b3ea757376cd8a3a980eDan Gohman memset(PhysRegUseDefLists, 0, sizeof(MachineOperand*)*TRI.getNumRegs()); 2462ed6b9ade63bf01717ce5274fa11e93e873d245Chris Lattner} 2562ed6b9ade63bf01717ce5274fa11e93e873d245Chris Lattner 2662ed6b9ade63bf01717ce5274fa11e93e873d245Chris LattnerMachineRegisterInfo::~MachineRegisterInfo() { 2762ed6b9ade63bf01717ce5274fa11e93e873d245Chris Lattner#ifndef NDEBUG 2862ed6b9ade63bf01717ce5274fa11e93e873d245Chris Lattner for (unsigned i = 0, e = VRegInfo.size(); i != e; ++i) 2962ed6b9ade63bf01717ce5274fa11e93e873d245Chris Lattner assert(VRegInfo[i].second == 0 && "Vreg use list non-empty still?"); 3062ed6b9ade63bf01717ce5274fa11e93e873d245Chris Lattner#endif 3162ed6b9ade63bf01717ce5274fa11e93e873d245Chris Lattner delete [] PhysRegUseDefLists; 3262ed6b9ade63bf01717ce5274fa11e93e873d245Chris Lattner} 3362ed6b9ade63bf01717ce5274fa11e93e873d245Chris Lattner 3462ed6b9ade63bf01717ce5274fa11e93e873d245Chris Lattner/// HandleVRegListReallocation - We just added a virtual register to the 3562ed6b9ade63bf01717ce5274fa11e93e873d245Chris Lattner/// VRegInfo info list and it reallocated. Update the use/def lists info 3662ed6b9ade63bf01717ce5274fa11e93e873d245Chris Lattner/// pointers. 3762ed6b9ade63bf01717ce5274fa11e93e873d245Chris Lattnervoid MachineRegisterInfo::HandleVRegListReallocation() { 3862ed6b9ade63bf01717ce5274fa11e93e873d245Chris Lattner // The back pointers for the vreg lists point into the previous vector. 3962ed6b9ade63bf01717ce5274fa11e93e873d245Chris Lattner // Update them to point to their correct slots. 4062ed6b9ade63bf01717ce5274fa11e93e873d245Chris Lattner for (unsigned i = 0, e = VRegInfo.size(); i != e; ++i) { 4162ed6b9ade63bf01717ce5274fa11e93e873d245Chris Lattner MachineOperand *List = VRegInfo[i].second; 4262ed6b9ade63bf01717ce5274fa11e93e873d245Chris Lattner if (!List) continue; 4362ed6b9ade63bf01717ce5274fa11e93e873d245Chris Lattner // Update the back-pointer to be accurate once more. 4462ed6b9ade63bf01717ce5274fa11e93e873d245Chris Lattner List->Contents.Reg.Prev = &VRegInfo[i].second; 4562ed6b9ade63bf01717ce5274fa11e93e873d245Chris Lattner } 4684bc5427d6883f73cfeae3da640acd011d35c006Chris Lattner} 47a91a7d594ff1e1503731ca92f72e627bdfd18f3fChris Lattner 48e138b3dd1ff02d826233482831318708a166ed93Chris Lattner/// replaceRegWith - Replace all instances of FromReg with ToReg in the 49e138b3dd1ff02d826233482831318708a166ed93Chris Lattner/// machine function. This is like llvm-level X->replaceAllUsesWith(Y), 50e138b3dd1ff02d826233482831318708a166ed93Chris Lattner/// except that it also changes any definitions of the register as well. 51e138b3dd1ff02d826233482831318708a166ed93Chris Lattnervoid MachineRegisterInfo::replaceRegWith(unsigned FromReg, unsigned ToReg) { 52e138b3dd1ff02d826233482831318708a166ed93Chris Lattner assert(FromReg != ToReg && "Cannot replace a reg with itself"); 53e138b3dd1ff02d826233482831318708a166ed93Chris Lattner 54e138b3dd1ff02d826233482831318708a166ed93Chris Lattner // TODO: This could be more efficient by bulk changing the operands. 55e138b3dd1ff02d826233482831318708a166ed93Chris Lattner for (reg_iterator I = reg_begin(FromReg), E = reg_end(); I != E; ) { 56e138b3dd1ff02d826233482831318708a166ed93Chris Lattner MachineOperand &O = I.getOperand(); 57e138b3dd1ff02d826233482831318708a166ed93Chris Lattner ++I; 58e138b3dd1ff02d826233482831318708a166ed93Chris Lattner O.setReg(ToReg); 59e138b3dd1ff02d826233482831318708a166ed93Chris Lattner } 60e138b3dd1ff02d826233482831318708a166ed93Chris Lattner} 61e138b3dd1ff02d826233482831318708a166ed93Chris Lattner 62a91a7d594ff1e1503731ca92f72e627bdfd18f3fChris Lattner 63a91a7d594ff1e1503731ca92f72e627bdfd18f3fChris Lattner/// getVRegDef - Return the machine instr that defines the specified virtual 64a91a7d594ff1e1503731ca92f72e627bdfd18f3fChris Lattner/// register or null if none is found. This assumes that the code is in SSA 65a91a7d594ff1e1503731ca92f72e627bdfd18f3fChris Lattner/// form, so there should only be one definition. 66a91a7d594ff1e1503731ca92f72e627bdfd18f3fChris LattnerMachineInstr *MachineRegisterInfo::getVRegDef(unsigned Reg) const { 676f0d024a534af18d9e60b3ea757376cd8a3a980eDan Gohman assert(Reg-TargetRegisterInfo::FirstVirtualRegister < VRegInfo.size() && 68a91a7d594ff1e1503731ca92f72e627bdfd18f3fChris Lattner "Invalid vreg!"); 69a91a7d594ff1e1503731ca92f72e627bdfd18f3fChris Lattner for (reg_iterator I = reg_begin(Reg), E = reg_end(); I != E; ++I) { 70a91a7d594ff1e1503731ca92f72e627bdfd18f3fChris Lattner // Since we are in SSA form, we can stop at the first definition. 71e138b3dd1ff02d826233482831318708a166ed93Chris Lattner if (I.getOperand().isDef()) 72e138b3dd1ff02d826233482831318708a166ed93Chris Lattner return &*I; 73a91a7d594ff1e1503731ca92f72e627bdfd18f3fChris Lattner } 74a91a7d594ff1e1503731ca92f72e627bdfd18f3fChris Lattner return 0; 75a91a7d594ff1e1503731ca92f72e627bdfd18f3fChris Lattner} 761eb5cf9c7d0b0b04402eddc007b0de414488baf4Evan Cheng 771eb5cf9c7d0b0b04402eddc007b0de414488baf4Evan Cheng 781eb5cf9c7d0b0b04402eddc007b0de414488baf4Evan Cheng#ifndef NDEBUG 791eb5cf9c7d0b0b04402eddc007b0de414488baf4Evan Chengvoid MachineRegisterInfo::dumpUses(unsigned Reg) const { 801eb5cf9c7d0b0b04402eddc007b0de414488baf4Evan Cheng for (use_iterator I = use_begin(Reg), E = use_end(); I != E; ++I) 811eb5cf9c7d0b0b04402eddc007b0de414488baf4Evan Cheng I.getOperand().getParent()->dump(); 821eb5cf9c7d0b0b04402eddc007b0de414488baf4Evan Cheng} 831eb5cf9c7d0b0b04402eddc007b0de414488baf4Evan Cheng#endif 84