X86FrameLowering.cpp revision 1f4b796b49d13075531ed43b35824ecc9d757467
131d157ae1ac2cd9c787dc3c1d28e64c682803844Jia Liu//===-- X86FrameLowering.cpp - X86 Frame Information ----------------------===// 233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov// 333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov// The LLVM Compiler Infrastructure 433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov// 533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov// This file is distributed under the University of Illinois Open Source 633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov// License. See LICENSE.TXT for details. 733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov// 833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov//===----------------------------------------------------------------------===// 933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov// 1016c29b5f285f375be53dabaa73e3e91107485fe4Anton Korobeynikov// This file contains the X86 implementation of TargetFrameLowering class. 1133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov// 1233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov//===----------------------------------------------------------------------===// 1333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 1416c29b5f285f375be53dabaa73e3e91107485fe4Anton Korobeynikov#include "X86FrameLowering.h" 1533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov#include "X86InstrBuilder.h" 1633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov#include "X86InstrInfo.h" 1733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov#include "X86MachineFunctionInfo.h" 1876927d758657b3a511c73467ec5a7288795c1513Rafael Espindola#include "X86Subtarget.h" 19d9e3385ced2dc887e2fe8e1c071bd2611e4d3edeAnton Korobeynikov#include "X86TargetMachine.h" 20d04a8d4b33ff316ca4cf961e06c9e312eff8e64fChandler Carruth#include "llvm/ADT/SmallSet.h" 2133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov#include "llvm/CodeGen/MachineFrameInfo.h" 2233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov#include "llvm/CodeGen/MachineFunction.h" 2333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov#include "llvm/CodeGen/MachineInstrBuilder.h" 2433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov#include "llvm/CodeGen/MachineModuleInfo.h" 2533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov#include "llvm/CodeGen/MachineRegisterInfo.h" 260b8c9a80f20772c3793201ab5b251d3520b9cea3Chandler Carruth#include "llvm/IR/DataLayout.h" 270b8c9a80f20772c3793201ab5b251d3520b9cea3Chandler Carruth#include "llvm/IR/Function.h" 28f0adba9a7ec8a3031876575a6ffb7db5f1b6f855Rafael Espindola#include "llvm/MC/MCAsmInfo.h" 296a6b8c3e96b9e1ca7092eafd0cfb219cbbfbdfc4Bill Wendling#include "llvm/MC/MCSymbol.h" 3033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov#include "llvm/Support/CommandLine.h" 31d04a8d4b33ff316ca4cf961e06c9e312eff8e64fChandler Carruth#include "llvm/Target/TargetOptions.h" 3233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 3333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikovusing namespace llvm; 3433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 3533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov// FIXME: completely move here. 3633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikovextern cl::opt<bool> ForceStackAlign; 3733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 3816c29b5f285f375be53dabaa73e3e91107485fe4Anton Korobeynikovbool X86FrameLowering::hasReservedCallFrame(const MachineFunction &MF) const { 39d0c38176690e9602a93a20a43f1bd084564a8116Anton Korobeynikov return !MF.getFrameInfo()->hasVarSizedObjects(); 40d0c38176690e9602a93a20a43f1bd084564a8116Anton Korobeynikov} 41d0c38176690e9602a93a20a43f1bd084564a8116Anton Korobeynikov 42d0c38176690e9602a93a20a43f1bd084564a8116Anton Korobeynikov/// hasFP - Return true if the specified function should have a dedicated frame 43d0c38176690e9602a93a20a43f1bd084564a8116Anton Korobeynikov/// pointer register. This is true if the function has variable sized allocas 44d0c38176690e9602a93a20a43f1bd084564a8116Anton Korobeynikov/// or if frame pointer elimination is disabled. 4516c29b5f285f375be53dabaa73e3e91107485fe4Anton Korobeynikovbool X86FrameLowering::hasFP(const MachineFunction &MF) const { 46d0c38176690e9602a93a20a43f1bd084564a8116Anton Korobeynikov const MachineFrameInfo *MFI = MF.getFrameInfo(); 47d0c38176690e9602a93a20a43f1bd084564a8116Anton Korobeynikov const MachineModuleInfo &MMI = MF.getMMI(); 483fb6eca0cd4c2b31b06543ca2ac60b9c91c2264dChad Rosier const TargetRegisterInfo *RegInfo = TM.getRegisterInfo(); 49d0c38176690e9602a93a20a43f1bd084564a8116Anton Korobeynikov 508a8d479214745c82ef00f08d4e4f1c173b5f9ce2Nick Lewycky return (MF.getTarget().Options.DisableFramePointerElim(MF) || 513fb6eca0cd4c2b31b06543ca2ac60b9c91c2264dChad Rosier RegInfo->needsStackRealignment(MF) || 52d0c38176690e9602a93a20a43f1bd084564a8116Anton Korobeynikov MFI->hasVarSizedObjects() || 53b56606274d43c7a3e01b18a08d1115fbf2889996Chad Rosier MFI->isFrameAddressTaken() || MF.hasMSInlineAsm() || 54d0c38176690e9602a93a20a43f1bd084564a8116Anton Korobeynikov MF.getInfo<X86MachineFunctionInfo>()->getForceFramePointer() || 55e208c491726bb1efbfc4fc05a9f73ad808432979Jakob Stoklund Olesen MMI.callsUnwindInit() || MMI.callsEHReturn()); 56d0c38176690e9602a93a20a43f1bd084564a8116Anton Korobeynikov} 57d0c38176690e9602a93a20a43f1bd084564a8116Anton Korobeynikov 58700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Benderskystatic unsigned getSUBriOpcode(unsigned IsLP64, int64_t Imm) { 59700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky if (IsLP64) { 6033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (isInt<8>(Imm)) 6133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov return X86::SUB64ri8; 6233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov return X86::SUB64ri32; 6333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } else { 6433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (isInt<8>(Imm)) 6533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov return X86::SUB32ri8; 6633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov return X86::SUB32ri; 6733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 6833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov} 6933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 7016221a60a00e52b078f6164ba4475c6e8e918e4bEli Benderskystatic unsigned getADDriOpcode(unsigned IsLP64, int64_t Imm) { 7116221a60a00e52b078f6164ba4475c6e8e918e4bEli Bendersky if (IsLP64) { 7233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (isInt<8>(Imm)) 7333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov return X86::ADD64ri8; 7433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov return X86::ADD64ri32; 7533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } else { 7633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (isInt<8>(Imm)) 7733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov return X86::ADD32ri8; 7833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov return X86::ADD32ri; 7933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 8033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov} 8133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 8216221a60a00e52b078f6164ba4475c6e8e918e4bEli Benderskystatic unsigned getLEArOpcode(unsigned IsLP64) { 8316221a60a00e52b078f6164ba4475c6e8e918e4bEli Bendersky return IsLP64 ? X86::LEA64r : X86::LEA32r; 84de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng} 85de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng 867158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng/// findDeadCallerSavedReg - Return a caller-saved register that isn't live 877158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng/// when it reaches the "return" instruction. We can then pop a stack object 887158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng/// to this register without worry about clobbering it. 897158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Chengstatic unsigned findDeadCallerSavedReg(MachineBasicBlock &MBB, 907158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng MachineBasicBlock::iterator &MBBI, 917158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng const TargetRegisterInfo &TRI, 927158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng bool Is64Bit) { 937158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng const MachineFunction *MF = MBB.getParent(); 947158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng const Function *F = MF->getFunction(); 957158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng if (!F || MF->getMMI().callsEHReturn()) 967158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng return 0; 977158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng 98e4fd907e72a599eddfa7a81eac4366b5b82523e3Craig Topper static const uint16_t CallerSavedRegs32Bit[] = { 9932a183c84ad0cbe492119c37f1a7941ace61dd79Andrew Trick X86::EAX, X86::EDX, X86::ECX, 0 1007158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng }; 1017158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng 102e4fd907e72a599eddfa7a81eac4366b5b82523e3Craig Topper static const uint16_t CallerSavedRegs64Bit[] = { 1037158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng X86::RAX, X86::RDX, X86::RCX, X86::RSI, X86::RDI, 10432a183c84ad0cbe492119c37f1a7941ace61dd79Andrew Trick X86::R8, X86::R9, X86::R10, X86::R11, 0 1057158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng }; 1067158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng 1077158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng unsigned Opc = MBBI->getOpcode(); 1087158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng switch (Opc) { 1097158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng default: return 0; 1107158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng case X86::RET: 1117158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng case X86::RETI: 1127158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng case X86::TCRETURNdi: 1137158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng case X86::TCRETURNri: 1147158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng case X86::TCRETURNmi: 1157158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng case X86::TCRETURNdi64: 1167158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng case X86::TCRETURNri64: 1177158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng case X86::TCRETURNmi64: 1187158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng case X86::EH_RETURN: 1197158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng case X86::EH_RETURN64: { 120e4fd907e72a599eddfa7a81eac4366b5b82523e3Craig Topper SmallSet<uint16_t, 8> Uses; 1217158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng for (unsigned i = 0, e = MBBI->getNumOperands(); i != e; ++i) { 1227158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng MachineOperand &MO = MBBI->getOperand(i); 1237158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng if (!MO.isReg() || MO.isDef()) 1247158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng continue; 1257158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng unsigned Reg = MO.getReg(); 1267158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng if (!Reg) 1277158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng continue; 128396618b43a85e12d290a90b181c6af5d7c0c5f11Jakob Stoklund Olesen for (MCRegAliasIterator AI(Reg, &TRI, true); AI.isValid(); ++AI) 129396618b43a85e12d290a90b181c6af5d7c0c5f11Jakob Stoklund Olesen Uses.insert(*AI); 1307158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng } 1317158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng 132e4fd907e72a599eddfa7a81eac4366b5b82523e3Craig Topper const uint16_t *CS = Is64Bit ? CallerSavedRegs64Bit : CallerSavedRegs32Bit; 1337158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng for (; *CS; ++CS) 1347158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng if (!Uses.count(*CS)) 1357158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng return *CS; 1367158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng } 1377158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng } 1387158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng 1397158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng return 0; 1407158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng} 1417158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng 1427158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng 14333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov/// emitSPUpdate - Emit a series of instructions to increment / decrement the 14433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov/// stack pointer by a constant value. 14533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikovstatic 14633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikovvoid emitSPUpdate(MachineBasicBlock &MBB, MachineBasicBlock::iterator &MBBI, 1477158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng unsigned StackPtr, int64_t NumBytes, 1482a1b60d791522d73be91d4281c90d25bd5e3d117Eli Bendersky bool Is64Bit, bool IsLP64, bool UseLEA, 14976ad43c6e1619ed4c087b8ccb2cd573eb9d7093eEric Christopher const TargetInstrInfo &TII, const TargetRegisterInfo &TRI) { 15033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov bool isSub = NumBytes < 0; 15133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov uint64_t Offset = isSub ? -NumBytes : NumBytes; 152de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng unsigned Opc; 153de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng if (UseLEA) 15416221a60a00e52b078f6164ba4475c6e8e918e4bEli Bendersky Opc = getLEArOpcode(IsLP64); 155de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng else 156de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng Opc = isSub 1572a1b60d791522d73be91d4281c90d25bd5e3d117Eli Bendersky ? getSUBriOpcode(IsLP64, Offset) 1582a1b60d791522d73be91d4281c90d25bd5e3d117Eli Bendersky : getADDriOpcode(IsLP64, Offset); 159de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng 16033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov uint64_t Chunk = (1LL << 31) - 1; 16176ad43c6e1619ed4c087b8ccb2cd573eb9d7093eEric Christopher DebugLoc DL = MBB.findDebugLoc(MBBI); 16233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 16333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov while (Offset) { 16433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov uint64_t ThisVal = (Offset > Chunk) ? Chunk : Offset; 1657158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng if (ThisVal == (Is64Bit ? 8 : 4)) { 1667158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng // Use push / pop instead. 1677158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng unsigned Reg = isSub 1681e08cd1eaef8acbcfaf7db48d859a29583c29897Dale Johannesen ? (unsigned)(Is64Bit ? X86::RAX : X86::EAX) 1697158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng : findDeadCallerSavedReg(MBB, MBBI, TRI, Is64Bit); 1707158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng if (Reg) { 1717158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng Opc = isSub 1727158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng ? (Is64Bit ? X86::PUSH64r : X86::PUSH32r) 1737158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng : (Is64Bit ? X86::POP64r : X86::POP32r); 174aff232a5941c9ffb7ad52e08f81ad53794fed56bCharles Davis MachineInstr *MI = BuildMI(MBB, MBBI, DL, TII.get(Opc)) 1757158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng .addReg(Reg, getDefRegState(!isSub) | getUndefRegState(isSub)); 176aff232a5941c9ffb7ad52e08f81ad53794fed56bCharles Davis if (isSub) 177aff232a5941c9ffb7ad52e08f81ad53794fed56bCharles Davis MI->setFlag(MachineInstr::FrameSetup); 1787158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng Offset -= ThisVal; 1797158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng continue; 1807158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng } 1817158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng } 1827158e08b8e619f4dcac9834c57f5f8afd6eea2ebEvan Cheng 183de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng MachineInstr *MI = NULL; 184de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng 185de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng if (UseLEA) { 186de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng MI = addRegOffset(BuildMI(MBB, MBBI, DL, TII.get(Opc), StackPtr), 187de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng StackPtr, false, isSub ? -ThisVal : ThisVal); 188de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng } else { 189de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng MI = BuildMI(MBB, MBBI, DL, TII.get(Opc), StackPtr) 190de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng .addReg(StackPtr) 191de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng .addImm(ThisVal); 192de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng MI->getOperand(3).setIsDead(); // The EFLAGS implicit def is dead. 193de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng } 194de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng 195aff232a5941c9ffb7ad52e08f81ad53794fed56bCharles Davis if (isSub) 196aff232a5941c9ffb7ad52e08f81ad53794fed56bCharles Davis MI->setFlag(MachineInstr::FrameSetup); 197de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng 19833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov Offset -= ThisVal; 19933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 20033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov} 20133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 20233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov/// mergeSPUpdatesUp - Merge two stack-manipulating instructions upper iterator. 20333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikovstatic 20433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikovvoid mergeSPUpdatesUp(MachineBasicBlock &MBB, MachineBasicBlock::iterator &MBBI, 20533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov unsigned StackPtr, uint64_t *NumBytes = NULL) { 20633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (MBBI == MBB.begin()) return; 20733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 20833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineBasicBlock::iterator PI = prior(MBBI); 20933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov unsigned Opc = PI->getOpcode(); 21033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if ((Opc == X86::ADD64ri32 || Opc == X86::ADD64ri8 || 211de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng Opc == X86::ADD32ri || Opc == X86::ADD32ri8 || 212de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng Opc == X86::LEA32r || Opc == X86::LEA64_32r) && 21333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov PI->getOperand(0).getReg() == StackPtr) { 21433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (NumBytes) 21533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov *NumBytes += PI->getOperand(2).getImm(); 21633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MBB.erase(PI); 21733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } else if ((Opc == X86::SUB64ri32 || Opc == X86::SUB64ri8 || 21833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov Opc == X86::SUB32ri || Opc == X86::SUB32ri8) && 21933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov PI->getOperand(0).getReg() == StackPtr) { 22033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (NumBytes) 22133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov *NumBytes -= PI->getOperand(2).getImm(); 22233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MBB.erase(PI); 22333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 22433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov} 22533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 22633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov/// mergeSPUpdatesDown - Merge two stack-manipulating instructions lower iterator. 22733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikovstatic 22833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikovvoid mergeSPUpdatesDown(MachineBasicBlock &MBB, 22933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineBasicBlock::iterator &MBBI, 23033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov unsigned StackPtr, uint64_t *NumBytes = NULL) { 231fc9261279aa140542cf9b7c2c384d000ad97aca0Sanjoy Das // FIXME: THIS ISN'T RUN!!! 23233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov return; 23333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 23433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (MBBI == MBB.end()) return; 23533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 23633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineBasicBlock::iterator NI = llvm::next(MBBI); 23733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (NI == MBB.end()) return; 23833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 23933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov unsigned Opc = NI->getOpcode(); 24033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if ((Opc == X86::ADD64ri32 || Opc == X86::ADD64ri8 || 24133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov Opc == X86::ADD32ri || Opc == X86::ADD32ri8) && 24233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov NI->getOperand(0).getReg() == StackPtr) { 24333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (NumBytes) 24433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov *NumBytes -= NI->getOperand(2).getImm(); 24533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MBB.erase(NI); 24633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MBBI = NI; 24733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } else if ((Opc == X86::SUB64ri32 || Opc == X86::SUB64ri8 || 24833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov Opc == X86::SUB32ri || Opc == X86::SUB32ri8) && 24933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov NI->getOperand(0).getReg() == StackPtr) { 25033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (NumBytes) 25133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov *NumBytes += NI->getOperand(2).getImm(); 25233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MBB.erase(NI); 25333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MBBI = NI; 25433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 25533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov} 25633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 25733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov/// mergeSPUpdates - Checks the instruction before/after the passed 258de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng/// instruction. If it is an ADD/SUB/LEA instruction it is deleted argument and the 259de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng/// stack adjustment is returned as a positive value for ADD/LEA and a negative for 26033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov/// SUB. 26133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikovstatic int mergeSPUpdates(MachineBasicBlock &MBB, 26233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineBasicBlock::iterator &MBBI, 26333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov unsigned StackPtr, 26433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov bool doMergeWithPrevious) { 26533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if ((doMergeWithPrevious && MBBI == MBB.begin()) || 26633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov (!doMergeWithPrevious && MBBI == MBB.end())) 26733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov return 0; 26833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 26933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineBasicBlock::iterator PI = doMergeWithPrevious ? prior(MBBI) : MBBI; 27033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineBasicBlock::iterator NI = doMergeWithPrevious ? 0 : llvm::next(MBBI); 27133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov unsigned Opc = PI->getOpcode(); 27233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov int Offset = 0; 27333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 27433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if ((Opc == X86::ADD64ri32 || Opc == X86::ADD64ri8 || 275de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng Opc == X86::ADD32ri || Opc == X86::ADD32ri8 || 276de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng Opc == X86::LEA32r || Opc == X86::LEA64_32r) && 27733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov PI->getOperand(0).getReg() == StackPtr){ 27833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov Offset += PI->getOperand(2).getImm(); 27933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MBB.erase(PI); 28033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (!doMergeWithPrevious) MBBI = NI; 28133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } else if ((Opc == X86::SUB64ri32 || Opc == X86::SUB64ri8 || 28233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov Opc == X86::SUB32ri || Opc == X86::SUB32ri8) && 28333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov PI->getOperand(0).getReg() == StackPtr) { 28433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov Offset -= PI->getOperand(2).getImm(); 28533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MBB.erase(PI); 28633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (!doMergeWithPrevious) MBBI = NI; 28733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 28833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 28933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov return Offset; 29033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov} 29133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 29233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikovstatic bool isEAXLiveIn(MachineFunction &MF) { 29333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov for (MachineRegisterInfo::livein_iterator II = MF.getRegInfo().livein_begin(), 29433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov EE = MF.getRegInfo().livein_end(); II != EE; ++II) { 29533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov unsigned Reg = II->first; 29633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 29733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (Reg == X86::EAX || Reg == X86::AX || 29833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov Reg == X86::AH || Reg == X86::AL) 29933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov return true; 30033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 30133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 30233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov return false; 30333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov} 30433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 30516c29b5f285f375be53dabaa73e3e91107485fe4Anton Korobeynikovvoid X86FrameLowering::emitCalleeSavedFrameMoves(MachineFunction &MF, 30609b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling MCSymbol *Label, 30709b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling unsigned FramePtr) const { 30833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineFrameInfo *MFI = MF.getFrameInfo(); 30933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineModuleInfo &MMI = MF.getMMI(); 31033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 31133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Add callee saved registers to move list. 31233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov const std::vector<CalleeSavedInfo> &CSI = MFI->getCalleeSavedInfo(); 31333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (CSI.empty()) return; 31433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 31533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov std::vector<MachineMove> &Moves = MMI.getFrameMoves(); 316aa3c2c09d9d5bc67c6ca2fbc6697257b15476684Michael Liao const X86RegisterInfo *RegInfo = TM.getRegisterInfo(); 317d0c38176690e9602a93a20a43f1bd084564a8116Anton Korobeynikov bool HasFP = hasFP(MF); 31833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 31933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Calculate amount of bytes used for return address storing. 320aa3c2c09d9d5bc67c6ca2fbc6697257b15476684Michael Liao int stackGrowth = -RegInfo->getSlotSize(); 32133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 32233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // FIXME: This is dirty hack. The code itself is pretty mess right now. 32333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // It should be rewritten from scratch and generalized sometimes. 32433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 3257a2bdde0a0eebcd2125055e0eacaca040f0b766cChris Lattner // Determine maximum offset (minimum due to stack growth). 32633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov int64_t MaxOffset = 0; 32733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov for (std::vector<CalleeSavedInfo>::const_iterator 32833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov I = CSI.begin(), E = CSI.end(); I != E; ++I) 32933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MaxOffset = std::min(MaxOffset, 33033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MFI->getObjectOffset(I->getFrameIdx())); 33133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 33233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Calculate offsets. 33333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov int64_t saveAreaOffset = (HasFP ? 3 : 2) * stackGrowth; 33433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov for (std::vector<CalleeSavedInfo>::const_iterator 33533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov I = CSI.begin(), E = CSI.end(); I != E; ++I) { 33633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov int64_t Offset = MFI->getObjectOffset(I->getFrameIdx()); 33733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov unsigned Reg = I->getReg(); 33833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov Offset = MaxOffset - Offset + saveAreaOffset; 33933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 34033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Don't output a new machine move if we're re-saving the frame 34133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // pointer. This happens when the PrologEpilogInserter has inserted an extra 34233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // "PUSH" of the frame pointer -- the "emitPrologue" method automatically 34333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // generates one when frame pointers are used. If we generate a "machine 34433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // move" for this extra "PUSH", the linker will lose track of the fact that 34533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // the frame pointer should have the value of the first "PUSH" when it's 34633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // trying to unwind. 3472763538609fd455d63c192b320c73fb5d48c3e47NAKAMURA Takumi // 34833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // FIXME: This looks inelegant. It's possibly correct, but it's covering up 34933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // another bug. I.e., one where we generate a prolog like this: 35033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // 35133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // pushl %ebp 35233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // movl %esp, %ebp 35333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // pushl %ebp 35433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // pushl %esi 35533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // ... 35633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // 35733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // The immediate re-push of EBP is unnecessary. At the least, it's an 35833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // optimization bug. EBP can be used as a scratch register in certain 35933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // cases, but probably not when we have a frame pointer. 36033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (HasFP && FramePtr == Reg) 36133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov continue; 36233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 36333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineLocation CSDst(MachineLocation::VirtualFP, Offset); 36433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineLocation CSSrc(Reg); 36533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov Moves.push_back(MachineMove(Label, CSDst, CSSrc)); 36633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 36733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov} 36833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 36909b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling/// getCompactUnwindRegNum - Get the compact unwind number for a given 37009b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling/// register. The number corresponds to the enum lists in 37109b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling/// compact_unwind_encoding.h. 3721f4b796b49d13075531ed43b35824ecc9d757467Bill Wendlingstatic int getCompactUnwindRegNum(unsigned Reg, bool is64Bit) { 3731f4b796b49d13075531ed43b35824ecc9d757467Bill Wendling static const uint16_t CU32BitRegs[] = { 3741f4b796b49d13075531ed43b35824ecc9d757467Bill Wendling X86::EBX, X86::ECX, X86::EDX, X86::EDI, X86::ESI, X86::EBP, 0 3751f4b796b49d13075531ed43b35824ecc9d757467Bill Wendling }; 3761f4b796b49d13075531ed43b35824ecc9d757467Bill Wendling static const uint16_t CU64BitRegs[] = { 3771f4b796b49d13075531ed43b35824ecc9d757467Bill Wendling X86::RBX, X86::R12, X86::R13, X86::R14, X86::R15, X86::RBP, 0 3781f4b796b49d13075531ed43b35824ecc9d757467Bill Wendling }; 3791f4b796b49d13075531ed43b35824ecc9d757467Bill Wendling const uint16_t *CURegs = is64Bit ? CU64BitRegs : CU32BitRegs; 38010e412ec6b761952b95710203e6d2d89f4fee53aBill Wendling for (int Idx = 1; *CURegs; ++CURegs, ++Idx) 38109b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling if (*CURegs == Reg) 38209b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling return Idx; 38309b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 38409b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling return -1; 38509b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling} 38609b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 38757a3cd2f326269dd1431cf430db50239a93450f2Bill Wendling// Number of registers that can be saved in a compact unwind encoding. 38857a3cd2f326269dd1431cf430db50239a93450f2Bill Wendling#define CU_NUM_SAVED_REGS 6 38957a3cd2f326269dd1431cf430db50239a93450f2Bill Wendling 39009b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling/// encodeCompactUnwindRegistersWithoutFrame - Create the permutation encoding 39109b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling/// used with frameless stacks. It is passed the number of registers to be saved 39209b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling/// and an array of the registers saved. 39357a3cd2f326269dd1431cf430db50239a93450f2Bill Wendlingstatic uint32_t 39457a3cd2f326269dd1431cf430db50239a93450f2Bill WendlingencodeCompactUnwindRegistersWithoutFrame(unsigned SavedRegs[CU_NUM_SAVED_REGS], 39557a3cd2f326269dd1431cf430db50239a93450f2Bill Wendling unsigned RegCount, bool Is64Bit) { 39609b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // The saved registers are numbered from 1 to 6. In order to encode the order 39709b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // in which they were saved, we re-number them according to their place in the 39809b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // register order. The re-numbering is relative to the last re-numbered 39909b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // register. E.g., if we have registers {6, 2, 4, 5} saved in that order: 40009b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // 40109b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // Orig Re-Num 40209b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // ---- ------ 40309b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // 6 6 40409b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // 2 2 40509b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // 4 3 40609b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // 5 3 40709b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // 40810e412ec6b761952b95710203e6d2d89f4fee53aBill Wendling for (unsigned i = 0; i != CU_NUM_SAVED_REGS; ++i) { 4091f4b796b49d13075531ed43b35824ecc9d757467Bill Wendling int CUReg = getCompactUnwindRegNum(SavedRegs[i], Is64Bit); 41009b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling if (CUReg == -1) return ~0U; 41109b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling SavedRegs[i] = CUReg; 41279df986c60094e9ea29f081295aea08b1680a999Bill Wendling } 41309b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 41410e412ec6b761952b95710203e6d2d89f4fee53aBill Wendling // Reverse the list. 41510e412ec6b761952b95710203e6d2d89f4fee53aBill Wendling std::swap(SavedRegs[0], SavedRegs[5]); 41610e412ec6b761952b95710203e6d2d89f4fee53aBill Wendling std::swap(SavedRegs[1], SavedRegs[4]); 41710e412ec6b761952b95710203e6d2d89f4fee53aBill Wendling std::swap(SavedRegs[2], SavedRegs[3]); 41810e412ec6b761952b95710203e6d2d89f4fee53aBill Wendling 41957a3cd2f326269dd1431cf430db50239a93450f2Bill Wendling uint32_t RenumRegs[CU_NUM_SAVED_REGS]; 42057a3cd2f326269dd1431cf430db50239a93450f2Bill Wendling for (unsigned i = CU_NUM_SAVED_REGS - RegCount; i < CU_NUM_SAVED_REGS; ++i) { 42109b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling unsigned Countless = 0; 42257a3cd2f326269dd1431cf430db50239a93450f2Bill Wendling for (unsigned j = CU_NUM_SAVED_REGS - RegCount; j < i; ++j) 42309b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling if (SavedRegs[j] < SavedRegs[i]) 42409b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling ++Countless; 42509b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 42609b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling RenumRegs[i] = SavedRegs[i] - Countless - 1; 42709b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling } 42809b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 42909b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // Take the renumbered values and encode them into a 10-bit number. 43009b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling uint32_t permutationEncoding = 0; 43109b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling switch (RegCount) { 43209b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling case 6: 43309b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling permutationEncoding |= 120 * RenumRegs[0] + 24 * RenumRegs[1] 43409b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling + 6 * RenumRegs[2] + 2 * RenumRegs[3] 43509b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling + RenumRegs[4]; 43609b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling break; 43709b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling case 5: 43809b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling permutationEncoding |= 120 * RenumRegs[1] + 24 * RenumRegs[2] 43909b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling + 6 * RenumRegs[3] + 2 * RenumRegs[4] 44009b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling + RenumRegs[5]; 44109b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling break; 44209b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling case 4: 44309b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling permutationEncoding |= 60 * RenumRegs[2] + 12 * RenumRegs[3] 44409b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling + 3 * RenumRegs[4] + RenumRegs[5]; 44509b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling break; 44609b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling case 3: 44709b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling permutationEncoding |= 20 * RenumRegs[3] + 4 * RenumRegs[4] 44809b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling + RenumRegs[5]; 44909b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling break; 45009b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling case 2: 45109b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling permutationEncoding |= 5 * RenumRegs[4] + RenumRegs[5]; 45209b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling break; 45309b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling case 1: 45409b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling permutationEncoding |= RenumRegs[5]; 45509b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling break; 45609b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling } 45709b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 45809b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling assert((permutationEncoding & 0x3FF) == permutationEncoding && 45909b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling "Invalid compact register encoding!"); 46009b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling return permutationEncoding; 46109b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling} 46209b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 46309b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling/// encodeCompactUnwindRegistersWithFrame - Return the registers encoded for a 46409b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling/// compact encoding with a frame pointer. 46557a3cd2f326269dd1431cf430db50239a93450f2Bill Wendlingstatic uint32_t 46657a3cd2f326269dd1431cf430db50239a93450f2Bill WendlingencodeCompactUnwindRegistersWithFrame(unsigned SavedRegs[CU_NUM_SAVED_REGS], 46757a3cd2f326269dd1431cf430db50239a93450f2Bill Wendling bool Is64Bit) { 46809b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // Encode the registers in the order they were saved, 3-bits per register. The 46986b1a7d61413aed40a68f98f1e8f17fd79ebd7a2Bill Wendling // registers are numbered from 1 to CU_NUM_SAVED_REGS. 47009b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling uint32_t RegEnc = 0; 471b4ee5168abd0580a29f5c9becce26e3ea7bb2b8dBill Wendling for (int I = CU_NUM_SAVED_REGS - 1, Idx = 0; I != -1; --I) { 47209b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling unsigned Reg = SavedRegs[I]; 47386b1a7d61413aed40a68f98f1e8f17fd79ebd7a2Bill Wendling if (Reg == 0) continue; 47486b1a7d61413aed40a68f98f1e8f17fd79ebd7a2Bill Wendling 4751f4b796b49d13075531ed43b35824ecc9d757467Bill Wendling int CURegNum = getCompactUnwindRegNum(Reg, Is64Bit); 47686b1a7d61413aed40a68f98f1e8f17fd79ebd7a2Bill Wendling if (CURegNum == -1) return ~0U; 47780caf9c2737d4f1bf5bae3a283fe9d538f5e2970Bill Wendling 47880caf9c2737d4f1bf5bae3a283fe9d538f5e2970Bill Wendling // Encode the 3-bit register number in order, skipping over 3-bits for each 47980caf9c2737d4f1bf5bae3a283fe9d538f5e2970Bill Wendling // register. 48086b1a7d61413aed40a68f98f1e8f17fd79ebd7a2Bill Wendling RegEnc |= (CURegNum & 0x7) << (Idx++ * 3); 48109b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling } 48209b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 483dec1f996152d4292133e81527ad710fbc1280946Jakob Stoklund Olesen assert((RegEnc & 0x3FFFF) == RegEnc && "Invalid compact register encoding!"); 48409b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling return RegEnc; 48509b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling} 48609b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 48709b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendlinguint32_t X86FrameLowering::getCompactUnwindEncoding(MachineFunction &MF) const { 48809b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling const X86RegisterInfo *RegInfo = TM.getRegisterInfo(); 48909b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling unsigned FramePtr = RegInfo->getFrameRegister(MF); 49009b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling unsigned StackPtr = RegInfo->getStackRegister(); 49109b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 49209b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling bool Is64Bit = STI.is64Bit(); 49309b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling bool HasFP = hasFP(MF); 49409b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 49557a3cd2f326269dd1431cf430db50239a93450f2Bill Wendling unsigned SavedRegs[CU_NUM_SAVED_REGS] = { 0, 0, 0, 0, 0, 0 }; 49610e412ec6b761952b95710203e6d2d89f4fee53aBill Wendling unsigned SavedRegIdx = 0; 49709b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 49809b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling unsigned OffsetSize = (Is64Bit ? 8 : 4); 49909b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 50009b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling unsigned PushInstr = (Is64Bit ? X86::PUSH64r : X86::PUSH32r); 50109b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling unsigned PushInstrSize = 1; 50209b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling unsigned MoveInstr = (Is64Bit ? X86::MOV64rr : X86::MOV32rr); 50309b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling unsigned MoveInstrSize = (Is64Bit ? 3 : 2); 50409b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling unsigned SubtractInstrIdx = (Is64Bit ? 3 : 2); 50509b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 506de77055a68a3fc495e01b682f00059af3e38822eBill Wendling unsigned StackDivide = (Is64Bit ? 8 : 4); 507de77055a68a3fc495e01b682f00059af3e38822eBill Wendling 50809b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling unsigned InstrOffset = 0; 50909b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling unsigned StackAdjust = 0; 51057a3cd2f326269dd1431cf430db50239a93450f2Bill Wendling unsigned StackSize = 0; 51109b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 51209b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling MachineBasicBlock &MBB = MF.front(); // Prologue is in entry BB. 51309b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling bool ExpectEnd = false; 51409b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling for (MachineBasicBlock::iterator 51509b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling MBBI = MBB.begin(), MBBE = MBB.end(); MBBI != MBBE; ++MBBI) { 51609b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling MachineInstr &MI = *MBBI; 51709b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling unsigned Opc = MI.getOpcode(); 51809b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling if (Opc == X86::PROLOG_LABEL) continue; 51909b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling if (!MI.getFlag(MachineInstr::FrameSetup)) break; 52009b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 52109b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // We don't exect any more prolog instructions. 52289ec1c5c9c744c125b61145ed59783eb5c68ebf8Bill Wendling if (ExpectEnd) return CU::UNWIND_MODE_DWARF; 52309b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 52409b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling if (Opc == PushInstr) { 52509b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // If there are too many saved registers, we cannot use compact encoding. 52689ec1c5c9c744c125b61145ed59783eb5c68ebf8Bill Wendling if (SavedRegIdx >= CU_NUM_SAVED_REGS) return CU::UNWIND_MODE_DWARF; 52709b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 52810e412ec6b761952b95710203e6d2d89f4fee53aBill Wendling SavedRegs[SavedRegIdx++] = MI.getOperand(0).getReg(); 52957a3cd2f326269dd1431cf430db50239a93450f2Bill Wendling StackAdjust += OffsetSize; 53009b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling InstrOffset += PushInstrSize; 53109b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling } else if (Opc == MoveInstr) { 53209b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling unsigned SrcReg = MI.getOperand(1).getReg(); 53309b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling unsigned DstReg = MI.getOperand(0).getReg(); 53409b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 53509b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling if (DstReg != FramePtr || SrcReg != StackPtr) 53689ec1c5c9c744c125b61145ed59783eb5c68ebf8Bill Wendling return CU::UNWIND_MODE_DWARF; 53709b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 53857a3cd2f326269dd1431cf430db50239a93450f2Bill Wendling StackAdjust = 0; 53909b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling memset(SavedRegs, 0, sizeof(SavedRegs)); 54010e412ec6b761952b95710203e6d2d89f4fee53aBill Wendling SavedRegIdx = 0; 54109b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling InstrOffset += MoveInstrSize; 54284d518af1991f581b748c4d11dbeb1c54573556bBill Wendling } else if (Opc == X86::SUB64ri32 || Opc == X86::SUB64ri8 || 54384d518af1991f581b748c4d11dbeb1c54573556bBill Wendling Opc == X86::SUB32ri || Opc == X86::SUB32ri8) { 54457a3cd2f326269dd1431cf430db50239a93450f2Bill Wendling if (StackSize) 54557a3cd2f326269dd1431cf430db50239a93450f2Bill Wendling // We already have a stack size. 54689ec1c5c9c744c125b61145ed59783eb5c68ebf8Bill Wendling return CU::UNWIND_MODE_DWARF; 54709b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 54809b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling if (!MI.getOperand(0).isReg() || 54909b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling MI.getOperand(0).getReg() != MI.getOperand(1).getReg() || 55009b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling MI.getOperand(0).getReg() != StackPtr || !MI.getOperand(2).isImm()) 55109b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // We need this to be a stack adjustment pointer. Something like: 55209b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // 55309b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // %RSP<def> = SUB64ri8 %RSP, 48 55489ec1c5c9c744c125b61145ed59783eb5c68ebf8Bill Wendling return CU::UNWIND_MODE_DWARF; 55509b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 55657a3cd2f326269dd1431cf430db50239a93450f2Bill Wendling StackSize = MI.getOperand(2).getImm() / StackDivide; 55709b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling SubtractInstrIdx += InstrOffset; 55809b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling ExpectEnd = true; 55909b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling } 56009b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling } 56109b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 56209b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // Encode that we are using EBP/RBP as the frame pointer. 56309b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling uint32_t CompactUnwindEncoding = 0; 56457a3cd2f326269dd1431cf430db50239a93450f2Bill Wendling StackAdjust /= StackDivide; 56509b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling if (HasFP) { 56657a3cd2f326269dd1431cf430db50239a93450f2Bill Wendling if ((StackAdjust & 0xFF) != StackAdjust) 56709b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // Offset was too big for compact encoding. 56889ec1c5c9c744c125b61145ed59783eb5c68ebf8Bill Wendling return CU::UNWIND_MODE_DWARF; 56909b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 57009b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // Get the encoding of the saved registers when we have a frame pointer. 57109b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling uint32_t RegEnc = encodeCompactUnwindRegistersWithFrame(SavedRegs, Is64Bit); 57289ec1c5c9c744c125b61145ed59783eb5c68ebf8Bill Wendling if (RegEnc == ~0U) return CU::UNWIND_MODE_DWARF; 57309b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 57489ec1c5c9c744c125b61145ed59783eb5c68ebf8Bill Wendling CompactUnwindEncoding |= CU::UNWIND_MODE_BP_FRAME; 57557a3cd2f326269dd1431cf430db50239a93450f2Bill Wendling CompactUnwindEncoding |= (StackAdjust & 0xFF) << 16; 57689ec1c5c9c744c125b61145ed59783eb5c68ebf8Bill Wendling CompactUnwindEncoding |= RegEnc & CU::UNWIND_BP_FRAME_REGISTERS; 57709b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling } else { 578b3ec329c14fa3d37b5963f188db54ba03c6b97c0Bill Wendling ++StackAdjust; 579b3ec329c14fa3d37b5963f188db54ba03c6b97c0Bill Wendling uint32_t TotalStackSize = StackAdjust + StackSize; 580581ac2723c5cb5182114092591eb5e21ceea2e77Bill Wendling if ((TotalStackSize & 0xFF) == TotalStackSize) { 5815b2c4978ce56455689c515c9d74cc1d92871f3bbBill Wendling // Frameless stack with a small stack size. 58289ec1c5c9c744c125b61145ed59783eb5c68ebf8Bill Wendling CompactUnwindEncoding |= CU::UNWIND_MODE_STACK_IMMD; 5835b2c4978ce56455689c515c9d74cc1d92871f3bbBill Wendling 5845b2c4978ce56455689c515c9d74cc1d92871f3bbBill Wendling // Encode the stack size. 585581ac2723c5cb5182114092591eb5e21ceea2e77Bill Wendling CompactUnwindEncoding |= (TotalStackSize & 0xFF) << 16; 58609b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling } else { 58757a3cd2f326269dd1431cf430db50239a93450f2Bill Wendling if ((StackAdjust & 0x7) != StackAdjust) 58809b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // The extra stack adjustments are too big for us to handle. 58989ec1c5c9c744c125b61145ed59783eb5c68ebf8Bill Wendling return CU::UNWIND_MODE_DWARF; 59009b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 59109b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // Frameless stack with an offset too large for us to encode compactly. 59289ec1c5c9c744c125b61145ed59783eb5c68ebf8Bill Wendling CompactUnwindEncoding |= CU::UNWIND_MODE_STACK_IND; 59309b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 59409b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // Encode the offset to the nnnnnn value in the 'subl $nnnnnn, ESP' 59509b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // instruction. 59609b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling CompactUnwindEncoding |= (SubtractInstrIdx & 0xFF) << 16; 59709b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 59857a3cd2f326269dd1431cf430db50239a93450f2Bill Wendling // Encode any extra stack stack adjustments (done via push instructions). 59957a3cd2f326269dd1431cf430db50239a93450f2Bill Wendling CompactUnwindEncoding |= (StackAdjust & 0x7) << 13; 60009b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling } 60109b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 6025b2c4978ce56455689c515c9d74cc1d92871f3bbBill Wendling // Encode the number of registers saved. 60310e412ec6b761952b95710203e6d2d89f4fee53aBill Wendling CompactUnwindEncoding |= (SavedRegIdx & 0x7) << 10; 60475e14e0ebd29bb2b1893948037c0ae5df4e09a41Bill Wendling 60509b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // Get the encoding of the saved registers when we don't have a frame 60609b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // pointer. 60757a3cd2f326269dd1431cf430db50239a93450f2Bill Wendling uint32_t RegEnc = 60810e412ec6b761952b95710203e6d2d89f4fee53aBill Wendling encodeCompactUnwindRegistersWithoutFrame(SavedRegs, SavedRegIdx, 60957a3cd2f326269dd1431cf430db50239a93450f2Bill Wendling Is64Bit); 61089ec1c5c9c744c125b61145ed59783eb5c68ebf8Bill Wendling if (RegEnc == ~0U) return CU::UNWIND_MODE_DWARF; 6115b2c4978ce56455689c515c9d74cc1d92871f3bbBill Wendling 6125b2c4978ce56455689c515c9d74cc1d92871f3bbBill Wendling // Encode the register encoding. 61389ec1c5c9c744c125b61145ed59783eb5c68ebf8Bill Wendling CompactUnwindEncoding |= 61489ec1c5c9c744c125b61145ed59783eb5c68ebf8Bill Wendling RegEnc & CU::UNWIND_FRAMELESS_STACK_REG_PERMUTATION; 61509b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling } 61609b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 61709b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling return CompactUnwindEncoding; 61809b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling} 61909b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 620677689cf5dc65404645462464682a0696cc84532Nadav Rotem/// usesTheStack - This function checks if any of the users of EFLAGS 621d0696ef8c33b9b2504e89bc0aab2ea99a6c90756Nadav Rotem/// copies the EFLAGS. We know that the code that lowers COPY of EFLAGS has 622d0696ef8c33b9b2504e89bc0aab2ea99a6c90756Nadav Rotem/// to use the stack, and if we don't adjust the stack we clobber the first 623d0696ef8c33b9b2504e89bc0aab2ea99a6c90756Nadav Rotem/// frame index. 624677689cf5dc65404645462464682a0696cc84532Nadav Rotem/// See X86InstrInfo::copyPhysReg. 625677689cf5dc65404645462464682a0696cc84532Nadav Rotemstatic bool usesTheStack(MachineFunction &MF) { 626d0696ef8c33b9b2504e89bc0aab2ea99a6c90756Nadav Rotem MachineRegisterInfo &MRI = MF.getRegInfo(); 627d0696ef8c33b9b2504e89bc0aab2ea99a6c90756Nadav Rotem 628d0696ef8c33b9b2504e89bc0aab2ea99a6c90756Nadav Rotem for (MachineRegisterInfo::reg_iterator ri = MRI.reg_begin(X86::EFLAGS), 629d0696ef8c33b9b2504e89bc0aab2ea99a6c90756Nadav Rotem re = MRI.reg_end(); ri != re; ++ri) 630d0696ef8c33b9b2504e89bc0aab2ea99a6c90756Nadav Rotem if (ri->isCopy()) 631d0696ef8c33b9b2504e89bc0aab2ea99a6c90756Nadav Rotem return true; 632d0696ef8c33b9b2504e89bc0aab2ea99a6c90756Nadav Rotem 633d0696ef8c33b9b2504e89bc0aab2ea99a6c90756Nadav Rotem return false; 634d0696ef8c33b9b2504e89bc0aab2ea99a6c90756Nadav Rotem} 635d0696ef8c33b9b2504e89bc0aab2ea99a6c90756Nadav Rotem 63633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov/// emitPrologue - Push callee-saved registers onto the stack, which 63733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov/// automatically adjust the stack pointer. Adjust the stack pointer to allocate 63833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov/// space for local variables. Also emit labels used by the exception handler to 63933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov/// generate the exception handling frames. 64016c29b5f285f375be53dabaa73e3e91107485fe4Anton Korobeynikovvoid X86FrameLowering::emitPrologue(MachineFunction &MF) const { 64133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineBasicBlock &MBB = MF.front(); // Prologue goes in entry BB. 64233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineBasicBlock::iterator MBBI = MBB.begin(); 64333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineFrameInfo *MFI = MF.getFrameInfo(); 64433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov const Function *Fn = MF.getFunction(); 645d9e3385ced2dc887e2fe8e1c071bd2611e4d3edeAnton Korobeynikov const X86RegisterInfo *RegInfo = TM.getRegisterInfo(); 646d9e3385ced2dc887e2fe8e1c071bd2611e4d3edeAnton Korobeynikov const X86InstrInfo &TII = *TM.getInstrInfo(); 64733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineModuleInfo &MMI = MF.getMMI(); 64833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov X86MachineFunctionInfo *X86FI = MF.getInfo<X86MachineFunctionInfo>(); 64933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov bool needsFrameMoves = MMI.hasDebugInfo() || 650fc2bb8c4448fa884d79e437cc2d2627a7d7740a8Rafael Espindola Fn->needsUnwindTableEntry(); 65133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov uint64_t MaxAlign = MFI->getMaxAlignment(); // Desired stack alignment. 65233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov uint64_t StackSize = MFI->getStackSize(); // Number of bytes to allocate. 653d0c38176690e9602a93a20a43f1bd084564a8116Anton Korobeynikov bool HasFP = hasFP(MF); 65433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov bool Is64Bit = STI.is64Bit(); 6552a1b60d791522d73be91d4281c90d25bd5e3d117Eli Bendersky bool IsLP64 = STI.isTarget64BitLP64(); 65633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov bool IsWin64 = STI.isTargetWin64(); 657de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng bool UseLEA = STI.useLeaForSP(); 65833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov unsigned StackAlign = getStackAlignment(); 65933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov unsigned SlotSize = RegInfo->getSlotSize(); 66033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov unsigned FramePtr = RegInfo->getFrameRegister(MF); 66133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov unsigned StackPtr = RegInfo->getStackRegister(); 6623f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier unsigned BasePtr = RegInfo->getBaseRegister(); 66333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov DebugLoc DL; 66433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 66533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // If we're forcing a stack realignment we can't rely on just the frame 66633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // info, we need to know the ABI stack alignment as well in case we 66733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // have a call out. Otherwise just make sure we have some alignment - we'll 66833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // go with the minimum SlotSize. 66933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (ForceStackAlign) { 67033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (MFI->hasCalls()) 67133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MaxAlign = (StackAlign > MaxAlign) ? StackAlign : MaxAlign; 67233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov else if (MaxAlign < SlotSize) 67333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MaxAlign = SlotSize; 67433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 67533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 67633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Add RETADDR move area to callee saved frame size. 67733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov int TailCallReturnAddrDelta = X86FI->getTCReturnAddrDelta(); 67833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (TailCallReturnAddrDelta < 0) 67933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov X86FI->setCalleeSavedFrameSize( 68033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov X86FI->getCalleeSavedFrameSize() - TailCallReturnAddrDelta); 68133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 68233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // If this is x86-64 and the Red Zone is not disabled, if we are a leaf 68333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // function, and use up to 128 bytes of stack space, don't have a frame 68433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // pointer, calls, or dynamic alloca then we do not need to adjust the 685d0696ef8c33b9b2504e89bc0aab2ea99a6c90756Nadav Rotem // stack pointer (we fit in the Red Zone). We also check that we don't 686d0696ef8c33b9b2504e89bc0aab2ea99a6c90756Nadav Rotem // push and pop from the stack. 687831737d329a727f53a1fb0572f7b7a8127208881Bill Wendling if (Is64Bit && !Fn->getAttributes().hasAttribute(AttributeSet::FunctionIndex, 688831737d329a727f53a1fb0572f7b7a8127208881Bill Wendling Attribute::NoRedZone) && 68933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov !RegInfo->needsStackRealignment(MF) && 6908a8d479214745c82ef00f08d4e4f1c173b5f9ce2Nick Lewycky !MFI->hasVarSizedObjects() && // No dynamic alloca. 6918a8d479214745c82ef00f08d4e4f1c173b5f9ce2Nick Lewycky !MFI->adjustsStack() && // No calls. 6928a8d479214745c82ef00f08d4e4f1c173b5f9ce2Nick Lewycky !IsWin64 && // Win64 has no Red Zone 693677689cf5dc65404645462464682a0696cc84532Nadav Rotem !usesTheStack(MF) && // Don't push and pop. 6948a8d479214745c82ef00f08d4e4f1c173b5f9ce2Nick Lewycky !MF.getTarget().Options.EnableSegmentedStacks) { // Regular stack 69533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov uint64_t MinSize = X86FI->getCalleeSavedFrameSize(); 69633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (HasFP) MinSize += SlotSize; 69733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov StackSize = std::max(MinSize, StackSize > 128 ? StackSize - 128 : 0); 69833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MFI->setStackSize(StackSize); 69933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 70033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 70133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Insert stack pointer adjustment for later moving of return addr. Only 70233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // applies to tail call optimized functions where the callee argument stack 70333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // size is bigger than the callers. 70433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (TailCallReturnAddrDelta < 0) { 70533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineInstr *MI = 70633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov BuildMI(MBB, MBBI, DL, 7072a1b60d791522d73be91d4281c90d25bd5e3d117Eli Bendersky TII.get(getSUBriOpcode(IsLP64, -TailCallReturnAddrDelta)), 70833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov StackPtr) 70933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov .addReg(StackPtr) 710aff232a5941c9ffb7ad52e08f81ad53794fed56bCharles Davis .addImm(-TailCallReturnAddrDelta) 711aff232a5941c9ffb7ad52e08f81ad53794fed56bCharles Davis .setMIFlag(MachineInstr::FrameSetup); 71233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MI->getOperand(3).setIsDead(); // The EFLAGS implicit def is dead. 71333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 71433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 71533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Mapping for machine moves: 71633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // 71733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // DST: VirtualFP AND 71833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // SRC: VirtualFP => DW_CFA_def_cfa_offset 71933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // ELSE => DW_CFA_def_cfa 72033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // 72133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // SRC: VirtualFP AND 72233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // DST: Register => DW_CFA_def_cfa_register 72333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // 72433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // ELSE 72533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // OFFSET < 0 => DW_CFA_offset_extended_sf 72633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // REG < 64 => DW_CFA_offset + Reg 72733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // ELSE => DW_CFA_offset_extended 72833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 72933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov std::vector<MachineMove> &Moves = MMI.getFrameMoves(); 73033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov uint64_t NumBytes = 0; 731aa3c2c09d9d5bc67c6ca2fbc6697257b15476684Michael Liao int stackGrowth = -SlotSize; 73233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 73333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (HasFP) { 73433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Calculate required stack adjustment. 73533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov uint64_t FrameSize = StackSize - SlotSize; 73699a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov if (RegInfo->needsStackRealignment(MF)) { 73799a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov // Callee-saved registers are pushed on stack before the stack 73899a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov // is realigned. 73999a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov FrameSize -= X86FI->getCalleeSavedFrameSize(); 74099a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov NumBytes = (FrameSize + MaxAlign - 1) / MaxAlign * MaxAlign; 74199a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov } else { 74299a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov NumBytes = FrameSize - X86FI->getCalleeSavedFrameSize(); 74399a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov } 74433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 74533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Get the offset of the stack slot for the EBP register, which is 74633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // guaranteed to be the last slot by processFunctionBeforeFrameFinalized. 74733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Update the frame offset adjustment. 74833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MFI->setOffsetAdjustment(-NumBytes); 74933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 75033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Save EBP/RBP into the appropriate stack slot. 75133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov BuildMI(MBB, MBBI, DL, TII.get(Is64Bit ? X86::PUSH64r : X86::PUSH32r)) 752aff232a5941c9ffb7ad52e08f81ad53794fed56bCharles Davis .addReg(FramePtr, RegState::Kill) 753aff232a5941c9ffb7ad52e08f81ad53794fed56bCharles Davis .setMIFlag(MachineInstr::FrameSetup); 75433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 75533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (needsFrameMoves) { 75633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Mark the place where EBP/RBP was saved. 75733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MCSymbol *FrameLabel = MMI.getContext().CreateTempSymbol(); 758fb4eb165d66b8ca5ae09c37d98d3ed937454b6afBill Wendling BuildMI(MBB, MBBI, DL, TII.get(X86::PROLOG_LABEL)) 759fb4eb165d66b8ca5ae09c37d98d3ed937454b6afBill Wendling .addSym(FrameLabel); 76033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 76133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Define the current CFA rule to use the provided offset. 76233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (StackSize) { 76333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineLocation SPDst(MachineLocation::VirtualFP); 76433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineLocation SPSrc(MachineLocation::VirtualFP, 2 * stackGrowth); 76533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov Moves.push_back(MachineMove(FrameLabel, SPDst, SPSrc)); 76633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } else { 76733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineLocation SPDst(StackPtr); 76833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineLocation SPSrc(StackPtr, stackGrowth); 76933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov Moves.push_back(MachineMove(FrameLabel, SPDst, SPSrc)); 77033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 77133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 77233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Change the rule for the FramePtr to be an "offset" rule. 77333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineLocation FPDst(MachineLocation::VirtualFP, 2 * stackGrowth); 77433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineLocation FPSrc(FramePtr); 77533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov Moves.push_back(MachineMove(FrameLabel, FPDst, FPSrc)); 77633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 77733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 77809b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // Update EBP with the new base value. 77933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov BuildMI(MBB, MBBI, DL, 78033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov TII.get(Is64Bit ? X86::MOV64rr : X86::MOV32rr), FramePtr) 781aff232a5941c9ffb7ad52e08f81ad53794fed56bCharles Davis .addReg(StackPtr) 782aff232a5941c9ffb7ad52e08f81ad53794fed56bCharles Davis .setMIFlag(MachineInstr::FrameSetup); 78333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 78433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (needsFrameMoves) { 78533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Mark effective beginning of when frame pointer becomes valid. 78633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MCSymbol *FrameLabel = MMI.getContext().CreateTempSymbol(); 787fb4eb165d66b8ca5ae09c37d98d3ed937454b6afBill Wendling BuildMI(MBB, MBBI, DL, TII.get(X86::PROLOG_LABEL)) 788fb4eb165d66b8ca5ae09c37d98d3ed937454b6afBill Wendling .addSym(FrameLabel); 78933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 79033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Define the current CFA to use the EBP/RBP register. 79133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineLocation FPDst(FramePtr); 79233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineLocation FPSrc(MachineLocation::VirtualFP); 79333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov Moves.push_back(MachineMove(FrameLabel, FPDst, FPSrc)); 79433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 79533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 79633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Mark the FramePtr as live-in in every block except the entry. 79733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov for (MachineFunction::iterator I = llvm::next(MF.begin()), E = MF.end(); 79833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov I != E; ++I) 79933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov I->addLiveIn(FramePtr); 80033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } else { 80133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov NumBytes = StackSize - X86FI->getCalleeSavedFrameSize(); 80233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 80333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 80433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Skip the callee-saved push instructions. 80533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov bool PushedRegs = false; 80633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov int StackOffset = 2 * stackGrowth; 80733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 80833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov while (MBBI != MBB.end() && 80933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov (MBBI->getOpcode() == X86::PUSH32r || 81033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MBBI->getOpcode() == X86::PUSH64r)) { 81133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov PushedRegs = true; 812fb4eb165d66b8ca5ae09c37d98d3ed937454b6afBill Wendling MBBI->setFlag(MachineInstr::FrameSetup); 81333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov ++MBBI; 81433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 81533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (!HasFP && needsFrameMoves) { 81633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Mark callee-saved push instruction. 81733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MCSymbol *Label = MMI.getContext().CreateTempSymbol(); 81833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov BuildMI(MBB, MBBI, DL, TII.get(X86::PROLOG_LABEL)).addSym(Label); 81933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 82033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Define the current CFA rule to use the provided offset. 82109b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling unsigned Ptr = StackSize ? MachineLocation::VirtualFP : StackPtr; 82233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineLocation SPDst(Ptr); 82333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineLocation SPSrc(Ptr, StackOffset); 82433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov Moves.push_back(MachineMove(Label, SPDst, SPSrc)); 82533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov StackOffset += stackGrowth; 82633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 82733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 82833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 82999a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov // Realign stack after we pushed callee-saved registers (so that we'll be 83099a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov // able to calculate their offsets from the frame pointer). 83199a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov 83299a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov // NOTE: We push the registers before realigning the stack, so 83399a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov // vector callee-saved (xmm) registers may be saved w/o proper 83499a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov // alignment in this way. However, currently these regs are saved in 83599a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov // stack slots (see X86FrameLowering::spillCalleeSavedRegisters()), so 83699a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov // this shouldn't be a problem. 83799a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov if (RegInfo->needsStackRealignment(MF)) { 83899a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov assert(HasFP && "There should be a frame pointer if stack is realigned."); 83999a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov MachineInstr *MI = 84099a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov BuildMI(MBB, MBBI, DL, 84199a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov TII.get(Is64Bit ? X86::AND64ri32 : X86::AND32ri), StackPtr) 84299a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov .addReg(StackPtr) 84399a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov .addImm(-MaxAlign) 84499a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov .setMIFlag(MachineInstr::FrameSetup); 84599a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov 84699a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov // The EFLAGS implicit def is dead. 84799a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov MI->getOperand(3).setIsDead(); 84899a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov } 84999a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov 85033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // If there is an SUB32ri of ESP immediately before this instruction, merge 85133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // the two. This can be the case when tail call elimination is enabled and 85233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // the callee has more arguments then the caller. 85333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov NumBytes -= mergeSPUpdates(MBB, MBBI, StackPtr, true); 85433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 85533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // If there is an ADD32ri or SUB32ri of ESP immediately after this 85633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // instruction, merge the two instructions. 85733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov mergeSPUpdatesDown(MBB, MBBI, StackPtr, &NumBytes); 85833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 85933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Adjust stack pointer: ESP -= numbytes. 86033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 86133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Windows and cygwin/mingw require a prologue helper routine when allocating 86233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // more than 4K bytes on the stack. Windows uses __chkstk and cygwin/mingw 86333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // uses __alloca. __alloca and the 32-bit version of __chkstk will probe the 86433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // stack and adjust the stack pointer in one go. The 64-bit version of 86533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // __chkstk is only responsible for probing the stack. The 64-bit prologue is 86633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // responsible for adjusting the stack pointer. Touching the stack at 4K 86733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // increments is necessary to ensure that the guard pages used by the OS 86833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // virtual memory manager are allocated in correct sequence. 869a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi if (NumBytes >= 4096 && STI.isTargetCOFF() && !STI.isTargetEnvMacho()) { 870a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi const char *StackProbeSymbol; 871a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi bool isSPUpdateNeeded = false; 872a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi 873a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi if (Is64Bit) { 874a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi if (STI.isTargetCygMing()) 875a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi StackProbeSymbol = "___chkstk"; 876a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi else { 877a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi StackProbeSymbol = "__chkstk"; 878a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi isSPUpdateNeeded = true; 879a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi } 880a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi } else if (STI.isTargetCygMing()) 881a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi StackProbeSymbol = "_alloca"; 882a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi else 883a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi StackProbeSymbol = "_chkstk"; 884a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi 88533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Check whether EAX is livein for this function. 88633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov bool isEAXAlive = isEAXLiveIn(MF); 88733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 888a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi if (isEAXAlive) { 889a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi // Sanity check that EAX is not livein for this function. 890a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi // It should not be, so throw an assert. 891a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi assert(!Is64Bit && "EAX is livein in x64 case!"); 892a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi 89333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Save EAX 89433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov BuildMI(MBB, MBBI, DL, TII.get(X86::PUSH32r)) 895fb4eb165d66b8ca5ae09c37d98d3ed937454b6afBill Wendling .addReg(X86::EAX, RegState::Kill) 896fb4eb165d66b8ca5ae09c37d98d3ed937454b6afBill Wendling .setMIFlag(MachineInstr::FrameSetup); 897a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi } 89833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 899a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi if (Is64Bit) { 900a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi // Handle the 64-bit Windows ABI case where we need to call __chkstk. 901a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi // Function prologue is responsible for adjusting the stack pointer. 902a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi BuildMI(MBB, MBBI, DL, TII.get(X86::MOV64ri), X86::RAX) 903fb4eb165d66b8ca5ae09c37d98d3ed937454b6afBill Wendling .addImm(NumBytes) 904fb4eb165d66b8ca5ae09c37d98d3ed937454b6afBill Wendling .setMIFlag(MachineInstr::FrameSetup); 905a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi } else { 906a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi // Allocate NumBytes-4 bytes on stack in case of isEAXAlive. 907a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi // We'll also use 4 already allocated bytes for EAX. 90833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov BuildMI(MBB, MBBI, DL, TII.get(X86::MOV32ri), X86::EAX) 909fb4eb165d66b8ca5ae09c37d98d3ed937454b6afBill Wendling .addImm(isEAXAlive ? NumBytes - 4 : NumBytes) 910fb4eb165d66b8ca5ae09c37d98d3ed937454b6afBill Wendling .setMIFlag(MachineInstr::FrameSetup); 911a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi } 912a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi 913a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi BuildMI(MBB, MBBI, DL, 914a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi TII.get(Is64Bit ? X86::W64ALLOCA : X86::CALLpcrel32)) 915a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi .addExternalSymbol(StackProbeSymbol) 916a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi .addReg(StackPtr, RegState::Define | RegState::Implicit) 917fb4eb165d66b8ca5ae09c37d98d3ed937454b6afBill Wendling .addReg(X86::EFLAGS, RegState::Define | RegState::Implicit) 918fb4eb165d66b8ca5ae09c37d98d3ed937454b6afBill Wendling .setMIFlag(MachineInstr::FrameSetup); 919a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi 920a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi // MSVC x64's __chkstk needs to adjust %rsp. 921a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi // FIXME: %rax preserves the offset and should be available. 922a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi if (isSPUpdateNeeded) 9232a1b60d791522d73be91d4281c90d25bd5e3d117Eli Bendersky emitSPUpdate(MBB, MBBI, StackPtr, -(int64_t)NumBytes, Is64Bit, IsLP64, 92476ad43c6e1619ed4c087b8ccb2cd573eb9d7093eEric Christopher UseLEA, TII, *RegInfo); 925a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi 926a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi if (isEAXAlive) { 927a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi // Restore EAX 928a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi MachineInstr *MI = addRegOffset(BuildMI(MF, DL, TII.get(X86::MOV32rm), 929a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi X86::EAX), 930a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi StackPtr, false, NumBytes - 4); 931fb4eb165d66b8ca5ae09c37d98d3ed937454b6afBill Wendling MI->setFlag(MachineInstr::FrameSetup); 932a2e0762fae050464494a50c8b5d53ac2f4ba738cNAKAMURA Takumi MBB.insert(MBBI, MI); 93333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 93433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } else if (NumBytes) 9352a1b60d791522d73be91d4281c90d25bd5e3d117Eli Bendersky emitSPUpdate(MBB, MBBI, StackPtr, -(int64_t)NumBytes, Is64Bit, IsLP64, 93676ad43c6e1619ed4c087b8ccb2cd573eb9d7093eEric Christopher UseLEA, TII, *RegInfo); 93733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 9383f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier // If we need a base pointer, set it up here. It's whatever the value 9393f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier // of the stack pointer is at this point. Any variable size objects 9403f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier // will be allocated after this, so we can still use the base pointer 9413f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier // to reference locals. 9423f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier if (RegInfo->hasBasePointer(MF)) { 9433f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier // Update the frame pointer with the current stack pointer. 9443f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier unsigned Opc = Is64Bit ? X86::MOV64rr : X86::MOV32rr; 9453f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier BuildMI(MBB, MBBI, DL, TII.get(Opc), BasePtr) 9463f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier .addReg(StackPtr) 9473f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier .setMIFlag(MachineInstr::FrameSetup); 9483f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier } 9493f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier 950f0adba9a7ec8a3031876575a6ffb7db5f1b6f855Rafael Espindola if (( (!HasFP && NumBytes) || PushedRegs) && needsFrameMoves) { 95133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Mark end of stack pointer adjustment. 95233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MCSymbol *Label = MMI.getContext().CreateTempSymbol(); 953fb4eb165d66b8ca5ae09c37d98d3ed937454b6afBill Wendling BuildMI(MBB, MBBI, DL, TII.get(X86::PROLOG_LABEL)) 954fb4eb165d66b8ca5ae09c37d98d3ed937454b6afBill Wendling .addSym(Label); 95533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 95633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (!HasFP && NumBytes) { 95733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Define the current CFA rule to use the provided offset. 95833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (StackSize) { 95933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineLocation SPDst(MachineLocation::VirtualFP); 96033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineLocation SPSrc(MachineLocation::VirtualFP, 96133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov -StackSize + stackGrowth); 96233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov Moves.push_back(MachineMove(Label, SPDst, SPSrc)); 96333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } else { 96433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineLocation SPDst(StackPtr); 96533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineLocation SPSrc(StackPtr, stackGrowth); 96633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov Moves.push_back(MachineMove(Label, SPDst, SPSrc)); 96733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 96833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 96933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 97033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Emit DWARF info specifying the offsets of the callee-saved registers. 97133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (PushedRegs) 97233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov emitCalleeSavedFrameMoves(MF, Label, HasFP ? FramePtr : StackPtr); 97333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 97409b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling 97509b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling // Darwin 10.7 and greater has support for compact unwind encoding. 976c8725d11f8756c57bdbceccc61062a9d560261c5Bill Wendling if (STI.getTargetTriple().isMacOSX() && 977ac86d43eae8bbfe5284d8e5fa17c141d1a7b1194Eli Friedman !STI.getTargetTriple().isMacOSXVersionLT(10, 7)) 97809b02c8dddf822e84c30cc08e7759d6ceebb2334Bill Wendling MMI.setCompactUnwindEncoding(getCompactUnwindEncoding(MF)); 97933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov} 98033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 98116c29b5f285f375be53dabaa73e3e91107485fe4Anton Korobeynikovvoid X86FrameLowering::emitEpilogue(MachineFunction &MF, 9823c2f0a11cce5a1e828e20675fa8467b624795e0aNick Lewycky MachineBasicBlock &MBB) const { 98333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov const MachineFrameInfo *MFI = MF.getFrameInfo(); 98433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov X86MachineFunctionInfo *X86FI = MF.getInfo<X86MachineFunctionInfo>(); 985d9e3385ced2dc887e2fe8e1c071bd2611e4d3edeAnton Korobeynikov const X86RegisterInfo *RegInfo = TM.getRegisterInfo(); 986d9e3385ced2dc887e2fe8e1c071bd2611e4d3edeAnton Korobeynikov const X86InstrInfo &TII = *TM.getInstrInfo(); 9874f28c1c71450c711e96aa283de53739d8b4504cdJakob Stoklund Olesen MachineBasicBlock::iterator MBBI = MBB.getLastNonDebugInstr(); 9884f28c1c71450c711e96aa283de53739d8b4504cdJakob Stoklund Olesen assert(MBBI != MBB.end() && "Returning block has no instructions"); 98933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov unsigned RetOpcode = MBBI->getOpcode(); 99033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov DebugLoc DL = MBBI->getDebugLoc(); 99133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov bool Is64Bit = STI.is64Bit(); 9922a1b60d791522d73be91d4281c90d25bd5e3d117Eli Bendersky bool IsLP64 = STI.isTarget64BitLP64(); 993de1df103b9c578d0a1609054a5944342c5d0ba23Evan Cheng bool UseLEA = STI.useLeaForSP(); 99433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov unsigned StackAlign = getStackAlignment(); 99533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov unsigned SlotSize = RegInfo->getSlotSize(); 99633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov unsigned FramePtr = RegInfo->getFrameRegister(MF); 99733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov unsigned StackPtr = RegInfo->getStackRegister(); 99833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 99933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov switch (RetOpcode) { 100033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov default: 100133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov llvm_unreachable("Can only insert epilog into returning blocks"); 100233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov case X86::RET: 100333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov case X86::RETI: 100433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov case X86::TCRETURNdi: 100533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov case X86::TCRETURNri: 100633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov case X86::TCRETURNmi: 100733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov case X86::TCRETURNdi64: 100833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov case X86::TCRETURNri64: 100933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov case X86::TCRETURNmi64: 101033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov case X86::EH_RETURN: 101133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov case X86::EH_RETURN64: 101233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov break; // These are ok 101333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 101433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 101533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Get the number of bytes to allocate from the FrameInfo. 101633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov uint64_t StackSize = MFI->getStackSize(); 101733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov uint64_t MaxAlign = MFI->getMaxAlignment(); 101833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov unsigned CSSize = X86FI->getCalleeSavedFrameSize(); 101933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov uint64_t NumBytes = 0; 102033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 102133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // If we're forcing a stack realignment we can't rely on just the frame 102233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // info, we need to know the ABI stack alignment as well in case we 102333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // have a call out. Otherwise just make sure we have some alignment - we'll 102433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // go with the minimum. 102533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (ForceStackAlign) { 102633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (MFI->hasCalls()) 102733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MaxAlign = (StackAlign > MaxAlign) ? StackAlign : MaxAlign; 102833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov else 102933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MaxAlign = MaxAlign ? MaxAlign : 4; 103033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 103133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 1032d0c38176690e9602a93a20a43f1bd084564a8116Anton Korobeynikov if (hasFP(MF)) { 103333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Calculate required stack adjustment. 103433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov uint64_t FrameSize = StackSize - SlotSize; 103599a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov if (RegInfo->needsStackRealignment(MF)) { 103699a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov // Callee-saved registers were pushed on stack before the stack 103799a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov // was realigned. 103899a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov FrameSize -= CSSize; 103999a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov NumBytes = (FrameSize + MaxAlign - 1) / MaxAlign * MaxAlign; 104099a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov } else { 104199a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov NumBytes = FrameSize - CSSize; 104299a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov } 104333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 104433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Pop EBP. 104533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov BuildMI(MBB, MBBI, DL, 104633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov TII.get(Is64Bit ? X86::POP64r : X86::POP32r), FramePtr); 104733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } else { 104833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov NumBytes = StackSize - CSSize; 104933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 105033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 105133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Skip the callee-saved pop instructions. 105233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov while (MBBI != MBB.begin()) { 105333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineBasicBlock::iterator PI = prior(MBBI); 105433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov unsigned Opc = PI->getOpcode(); 105533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 10564f28c1c71450c711e96aa283de53739d8b4504cdJakob Stoklund Olesen if (Opc != X86::POP32r && Opc != X86::POP64r && Opc != X86::DBG_VALUE && 10575a96b3dad2f634c9081c8b2b6c2575441dc5a2bdEvan Cheng !PI->isTerminator()) 105833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov break; 105933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 106033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov --MBBI; 106133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 106299a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov MachineBasicBlock::iterator FirstCSPop = MBBI; 106333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 106433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov DL = MBBI->getDebugLoc(); 106533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 106633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // If there is an ADD32ri or SUB32ri of ESP immediately before this 106733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // instruction, merge the two instructions. 106833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (NumBytes || MFI->hasVarSizedObjects()) 106933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov mergeSPUpdatesUp(MBB, MBBI, StackPtr, &NumBytes); 107033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 107133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // If dynamic alloca is used, then reset esp to point to the last callee-saved 107233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // slot before popping them off! Same applies for the case, when stack was 107333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // realigned. 107499a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov if (RegInfo->needsStackRealignment(MF) || MFI->hasVarSizedObjects()) { 107599a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov if (RegInfo->needsStackRealignment(MF)) 107699a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov MBBI = FirstCSPop; 107799a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov if (CSSize != 0) { 107816221a60a00e52b078f6164ba4475c6e8e918e4bEli Bendersky unsigned Opc = getLEArOpcode(IsLP64); 107999a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov addRegOffset(BuildMI(MBB, MBBI, DL, TII.get(Opc), StackPtr), 108099a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov FramePtr, false, -CSSize); 108133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } else { 108299a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov unsigned Opc = (Is64Bit ? X86::MOV64rr : X86::MOV32rr); 108399a92f269d4ea6f13a9858bb883e13382d021120Alexey Samsonov BuildMI(MBB, MBBI, DL, TII.get(Opc), StackPtr) 108433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov .addReg(FramePtr); 108533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 108633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } else if (NumBytes) { 108733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Adjust stack pointer back: ESP += numbytes. 10882a1b60d791522d73be91d4281c90d25bd5e3d117Eli Bendersky emitSPUpdate(MBB, MBBI, StackPtr, NumBytes, Is64Bit, IsLP64, UseLEA, 10892a1b60d791522d73be91d4281c90d25bd5e3d117Eli Bendersky TII, *RegInfo); 109033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 109133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 109233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // We're returning from function via eh_return. 109333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (RetOpcode == X86::EH_RETURN || RetOpcode == X86::EH_RETURN64) { 10944f28c1c71450c711e96aa283de53739d8b4504cdJakob Stoklund Olesen MBBI = MBB.getLastNonDebugInstr(); 109533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineOperand &DestAddr = MBBI->getOperand(0); 109633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov assert(DestAddr.isReg() && "Offset should be in register!"); 109733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov BuildMI(MBB, MBBI, DL, 109833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov TII.get(Is64Bit ? X86::MOV64rr : X86::MOV32rr), 109933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov StackPtr).addReg(DestAddr.getReg()); 110033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } else if (RetOpcode == X86::TCRETURNri || RetOpcode == X86::TCRETURNdi || 110133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov RetOpcode == X86::TCRETURNmi || 110233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov RetOpcode == X86::TCRETURNri64 || RetOpcode == X86::TCRETURNdi64 || 110333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov RetOpcode == X86::TCRETURNmi64) { 110433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov bool isMem = RetOpcode == X86::TCRETURNmi || RetOpcode == X86::TCRETURNmi64; 110533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Tail call return: adjust the stack pointer and jump to callee. 1106f7ca976e74eafeeab0e9097f0fb07d6bb447415bJakob Stoklund Olesen MBBI = MBB.getLastNonDebugInstr(); 110733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineOperand &JumpTarget = MBBI->getOperand(0); 110833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineOperand &StackAdjust = MBBI->getOperand(isMem ? 5 : 1); 110933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov assert(StackAdjust.isImm() && "Expecting immediate value."); 111033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 111133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Adjust stack pointer. 111233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov int StackAdj = StackAdjust.getImm(); 111333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov int MaxTCDelta = X86FI->getTCReturnAddrDelta(); 111433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov int Offset = 0; 111533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov assert(MaxTCDelta <= 0 && "MaxTCDelta should never be positive"); 111633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 111733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Incoporate the retaddr area. 111833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov Offset = StackAdj-MaxTCDelta; 111933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov assert(Offset >= 0 && "Offset should never be negative"); 112033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 112133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (Offset) { 11227a2bdde0a0eebcd2125055e0eacaca040f0b766cChris Lattner // Check for possible merge with preceding ADD instruction. 112333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov Offset += mergeSPUpdates(MBB, MBBI, StackPtr, true); 11242a1b60d791522d73be91d4281c90d25bd5e3d117Eli Bendersky emitSPUpdate(MBB, MBBI, StackPtr, Offset, Is64Bit, IsLP64, 11252a1b60d791522d73be91d4281c90d25bd5e3d117Eli Bendersky UseLEA, TII, *RegInfo); 112633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 112733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 112833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Jump to label or value in register. 112933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov if (RetOpcode == X86::TCRETURNdi || RetOpcode == X86::TCRETURNdi64) { 11303d2125c9dbac695c93f42c0f59fd040e413fd711Evan Cheng MachineInstrBuilder MIB = 11313d2125c9dbac695c93f42c0f59fd040e413fd711Evan Cheng BuildMI(MBB, MBBI, DL, TII.get((RetOpcode == X86::TCRETURNdi) 11323d2125c9dbac695c93f42c0f59fd040e413fd711Evan Cheng ? X86::TAILJMPd : X86::TAILJMPd64)); 11333d2125c9dbac695c93f42c0f59fd040e413fd711Evan Cheng if (JumpTarget.isGlobal()) 11343d2125c9dbac695c93f42c0f59fd040e413fd711Evan Cheng MIB.addGlobalAddress(JumpTarget.getGlobal(), JumpTarget.getOffset(), 11353d2125c9dbac695c93f42c0f59fd040e413fd711Evan Cheng JumpTarget.getTargetFlags()); 11363d2125c9dbac695c93f42c0f59fd040e413fd711Evan Cheng else { 11373d2125c9dbac695c93f42c0f59fd040e413fd711Evan Cheng assert(JumpTarget.isSymbol()); 11383d2125c9dbac695c93f42c0f59fd040e413fd711Evan Cheng MIB.addExternalSymbol(JumpTarget.getSymbolName(), 11393d2125c9dbac695c93f42c0f59fd040e413fd711Evan Cheng JumpTarget.getTargetFlags()); 11403d2125c9dbac695c93f42c0f59fd040e413fd711Evan Cheng } 114133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } else if (RetOpcode == X86::TCRETURNmi || RetOpcode == X86::TCRETURNmi64) { 114233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineInstrBuilder MIB = 114333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov BuildMI(MBB, MBBI, DL, TII.get((RetOpcode == X86::TCRETURNmi) 114433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov ? X86::TAILJMPm : X86::TAILJMPm64)); 114533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov for (unsigned i = 0; i != 5; ++i) 114633464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MIB.addOperand(MBBI->getOperand(i)); 114733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } else if (RetOpcode == X86::TCRETURNri64) { 114833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov BuildMI(MBB, MBBI, DL, TII.get(X86::TAILJMPr64)). 114933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov addReg(JumpTarget.getReg(), RegState::Kill); 115033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } else { 115133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov BuildMI(MBB, MBBI, DL, TII.get(X86::TAILJMPr)). 115233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov addReg(JumpTarget.getReg(), RegState::Kill); 115333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 115433464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 115533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MachineInstr *NewMI = prior(MBBI); 1156be06aacaa9a270384599bbfa850b967e9996b9fbJakob Stoklund Olesen NewMI->copyImplicitOps(MF, MBBI); 115733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 115833464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Delete the pseudo instruction TCRETURN. 115933464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov MBB.erase(MBBI); 116033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } else if ((RetOpcode == X86::RET || RetOpcode == X86::RETI) && 116133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov (X86FI->getTCReturnAddrDelta() < 0)) { 116233464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov // Add the return addr area delta back since we are not tail calling. 116333464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov int delta = -1*X86FI->getTCReturnAddrDelta(); 11644f28c1c71450c711e96aa283de53739d8b4504cdJakob Stoklund Olesen MBBI = MBB.getLastNonDebugInstr(); 116533464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov 11667a2bdde0a0eebcd2125055e0eacaca040f0b766cChris Lattner // Check for possible merge with preceding ADD instruction. 116733464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov delta += mergeSPUpdates(MBB, MBBI, StackPtr, true); 11682a1b60d791522d73be91d4281c90d25bd5e3d117Eli Bendersky emitSPUpdate(MBB, MBBI, StackPtr, delta, Is64Bit, IsLP64, UseLEA, TII, 11692a1b60d791522d73be91d4281c90d25bd5e3d117Eli Bendersky *RegInfo); 117033464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov } 117133464912237efaa0ed7060829e66b59055bdd48bAnton Korobeynikov} 1172d9e3385ced2dc887e2fe8e1c071bd2611e4d3edeAnton Korobeynikov 117316c29b5f285f375be53dabaa73e3e91107485fe4Anton Korobeynikovint X86FrameLowering::getFrameIndexOffset(const MachineFunction &MF, int FI) const { 11743fb6eca0cd4c2b31b06543ca2ac60b9c91c2264dChad Rosier const X86RegisterInfo *RegInfo = 117582f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov static_cast<const X86RegisterInfo*>(MF.getTarget().getRegisterInfo()); 117682f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov const MachineFrameInfo *MFI = MF.getFrameInfo(); 117782f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov int Offset = MFI->getObjectOffset(FI) - getOffsetOfLocalArea(); 117882f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov uint64_t StackSize = MFI->getStackSize(); 117982f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov 11803f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier if (RegInfo->hasBasePointer(MF)) { 11813f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier assert (hasFP(MF) && "VLAs and dynamic stack realign, but no FP?!"); 11823f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier if (FI < 0) { 11833f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier // Skip the saved EBP. 11843f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier return Offset + RegInfo->getSlotSize(); 11853f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier } else { 11863f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier assert((-(Offset + StackSize)) % MFI->getObjectAlignment(FI) == 0); 11873f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier return Offset + StackSize; 11883f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier } 11893f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier } else if (RegInfo->needsStackRealignment(MF)) { 119082f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov if (FI < 0) { 119182f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov // Skip the saved EBP. 11923fb6eca0cd4c2b31b06543ca2ac60b9c91c2264dChad Rosier return Offset + RegInfo->getSlotSize(); 119382f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov } else { 119417001ce25cc205ac1cd2604492c2bce310964220Duncan Sands assert((-(Offset + StackSize)) % MFI->getObjectAlignment(FI) == 0); 119582f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov return Offset + StackSize; 119682f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov } 119782f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov // FIXME: Support tail calls 119882f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov } else { 119982f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov if (!hasFP(MF)) 120082f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov return Offset + StackSize; 120182f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov 120282f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov // Skip the saved EBP. 12033fb6eca0cd4c2b31b06543ca2ac60b9c91c2264dChad Rosier Offset += RegInfo->getSlotSize(); 120482f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov 120582f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov // Skip the RETADDR move area 120682f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov const X86MachineFunctionInfo *X86FI = MF.getInfo<X86MachineFunctionInfo>(); 120782f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov int TailCallReturnAddrDelta = X86FI->getTCReturnAddrDelta(); 120882f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov if (TailCallReturnAddrDelta < 0) 120982f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov Offset -= TailCallReturnAddrDelta; 121082f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov } 121182f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov 121282f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov return Offset; 121382f58740c76b42af8370247b23677a0318f6dde8Anton Korobeynikov} 1214cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov 1215d07d06ceef942c478c0f75a4c4d7442e61ddff1dAlexey Samsonovint X86FrameLowering::getFrameIndexReference(const MachineFunction &MF, int FI, 1216d07d06ceef942c478c0f75a4c4d7442e61ddff1dAlexey Samsonov unsigned &FrameReg) const { 12173fb6eca0cd4c2b31b06543ca2ac60b9c91c2264dChad Rosier const X86RegisterInfo *RegInfo = 1218d07d06ceef942c478c0f75a4c4d7442e61ddff1dAlexey Samsonov static_cast<const X86RegisterInfo*>(MF.getTarget().getRegisterInfo()); 1219d07d06ceef942c478c0f75a4c4d7442e61ddff1dAlexey Samsonov // We can't calculate offset from frame pointer if the stack is realigned, 12203f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier // so enforce usage of stack/base pointer. The base pointer is used when we 12213f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier // have dynamic allocas in addition to dynamic realignment. 12223f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier if (RegInfo->hasBasePointer(MF)) 12233f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier FrameReg = RegInfo->getBaseRegister(); 12243f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier else if (RegInfo->needsStackRealignment(MF)) 12253f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier FrameReg = RegInfo->getStackRegister(); 12263f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier else 12273f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier FrameReg = RegInfo->getFrameRegister(MF); 1228d07d06ceef942c478c0f75a4c4d7442e61ddff1dAlexey Samsonov return getFrameIndexOffset(MF, FI); 1229d07d06ceef942c478c0f75a4c4d7442e61ddff1dAlexey Samsonov} 1230d07d06ceef942c478c0f75a4c4d7442e61ddff1dAlexey Samsonov 123116c29b5f285f375be53dabaa73e3e91107485fe4Anton Korobeynikovbool X86FrameLowering::spillCalleeSavedRegisters(MachineBasicBlock &MBB, 1232cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov MachineBasicBlock::iterator MI, 1233cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov const std::vector<CalleeSavedInfo> &CSI, 1234cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov const TargetRegisterInfo *TRI) const { 1235cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov if (CSI.empty()) 1236cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov return false; 1237cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov 1238cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov DebugLoc DL = MBB.findDebugLoc(MI); 1239cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov 1240cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov MachineFunction &MF = *MBB.getParent(); 1241cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov 1242cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov unsigned SlotSize = STI.is64Bit() ? 8 : 4; 1243cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov unsigned FPReg = TRI->getFrameRegister(MF); 1244cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov unsigned CalleeFrameSize = 0; 1245cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov 1246cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov const TargetInstrInfo &TII = *MF.getTarget().getInstrInfo(); 1247cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov X86MachineFunctionInfo *X86FI = MF.getInfo<X86MachineFunctionInfo>(); 1248cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov 1249419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi // Push GPRs. It increases frame size. 1250cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov unsigned Opc = STI.is64Bit() ? X86::PUSH64r : X86::PUSH32r; 1251cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov for (unsigned i = CSI.size(); i != 0; --i) { 1252cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov unsigned Reg = CSI[i-1].getReg(); 1253419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi if (!X86::GR64RegClass.contains(Reg) && 1254419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi !X86::GR32RegClass.contains(Reg)) 1255419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi continue; 1256cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov // Add the callee-saved register as live-in. It's killed at the spill. 1257cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov MBB.addLiveIn(Reg); 1258cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov if (Reg == FPReg) 1259cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov // X86RegisterInfo::emitPrologue will handle spilling of frame register. 1260cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov continue; 1261419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi CalleeFrameSize += SlotSize; 1262aff232a5941c9ffb7ad52e08f81ad53794fed56bCharles Davis BuildMI(MBB, MI, DL, TII.get(Opc)).addReg(Reg, RegState::Kill) 1263aff232a5941c9ffb7ad52e08f81ad53794fed56bCharles Davis .setMIFlag(MachineInstr::FrameSetup); 1264cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov } 1265cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov 1266cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov X86FI->setCalleeSavedFrameSize(CalleeFrameSize); 1267419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi 1268419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi // Make XMM regs spilled. X86 does not have ability of push/pop XMM. 1269419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi // It can be done by spilling XMMs to stack frame. 1270419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi // Note that only Win64 ABI might spill XMMs. 1271419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi for (unsigned i = CSI.size(); i != 0; --i) { 1272419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi unsigned Reg = CSI[i-1].getReg(); 1273419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi if (X86::GR64RegClass.contains(Reg) || 1274419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi X86::GR32RegClass.contains(Reg)) 1275419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi continue; 1276419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi // Add the callee-saved register as live-in. It's killed at the spill. 1277419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi MBB.addLiveIn(Reg); 1278419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi const TargetRegisterClass *RC = TRI->getMinimalPhysRegClass(Reg); 1279419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi TII.storeRegToStackSlot(MBB, MI, Reg, true, CSI[i-1].getFrameIdx(), 1280419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi RC, TRI); 1281419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi } 1282419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi 1283cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov return true; 1284cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov} 1285cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov 128616c29b5f285f375be53dabaa73e3e91107485fe4Anton Korobeynikovbool X86FrameLowering::restoreCalleeSavedRegisters(MachineBasicBlock &MBB, 1287cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov MachineBasicBlock::iterator MI, 1288cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov const std::vector<CalleeSavedInfo> &CSI, 1289cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov const TargetRegisterInfo *TRI) const { 1290cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov if (CSI.empty()) 1291cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov return false; 1292cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov 1293cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov DebugLoc DL = MBB.findDebugLoc(MI); 1294cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov 1295cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov MachineFunction &MF = *MBB.getParent(); 1296cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov const TargetInstrInfo &TII = *MF.getTarget().getInstrInfo(); 1297419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi 1298419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi // Reload XMMs from stack frame. 1299419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi for (unsigned i = 0, e = CSI.size(); i != e; ++i) { 1300419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi unsigned Reg = CSI[i].getReg(); 1301419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi if (X86::GR64RegClass.contains(Reg) || 1302419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi X86::GR32RegClass.contains(Reg)) 1303419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi continue; 1304419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi const TargetRegisterClass *RC = TRI->getMinimalPhysRegClass(Reg); 1305419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi TII.loadRegFromStackSlot(MBB, MI, Reg, CSI[i].getFrameIdx(), 1306419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi RC, TRI); 1307419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi } 1308419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi 1309419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi // POP GPRs. 1310cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov unsigned FPReg = TRI->getFrameRegister(MF); 1311cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov unsigned Opc = STI.is64Bit() ? X86::POP64r : X86::POP32r; 1312cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov for (unsigned i = 0, e = CSI.size(); i != e; ++i) { 1313cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov unsigned Reg = CSI[i].getReg(); 1314419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi if (!X86::GR64RegClass.contains(Reg) && 1315419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi !X86::GR32RegClass.contains(Reg)) 1316419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi continue; 1317cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov if (Reg == FPReg) 1318cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov // X86RegisterInfo::emitEpilogue will handle restoring of frame register. 1319cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov continue; 1320419f23278388a8999b5c0bbe73ce823f63747f28NAKAMURA Takumi BuildMI(MBB, MI, DL, TII.get(Opc), Reg); 1321cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov } 1322cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov return true; 1323cd775ceff0b25a0b026f643a7990c2924bd310a3Anton Korobeynikov} 132494c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov 132594c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikovvoid 132616c29b5f285f375be53dabaa73e3e91107485fe4Anton KorobeynikovX86FrameLowering::processFunctionBeforeCalleeSavedScan(MachineFunction &MF, 132794c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov RegScavenger *RS) const { 132894c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov MachineFrameInfo *MFI = MF.getFrameInfo(); 132994c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov const X86RegisterInfo *RegInfo = TM.getRegisterInfo(); 133094c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov unsigned SlotSize = RegInfo->getSlotSize(); 133194c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov 133294c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov X86MachineFunctionInfo *X86FI = MF.getInfo<X86MachineFunctionInfo>(); 133394c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov int32_t TailCallReturnAddrDelta = X86FI->getTCReturnAddrDelta(); 133494c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov 133594c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov if (TailCallReturnAddrDelta < 0) { 133694c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov // create RETURNADDR area 133794c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov // arg 133894c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov // arg 133994c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov // RETADDR 134094c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov // { ... 134194c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov // RETADDR area 134294c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov // ... 134394c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov // } 134494c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov // [EBP] 134594c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov MFI->CreateFixedObject(-TailCallReturnAddrDelta, 134694c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov (-1U*SlotSize)+TailCallReturnAddrDelta, true); 134794c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov } 134894c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov 134994c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov if (hasFP(MF)) { 135094c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov assert((TailCallReturnAddrDelta <= 0) && 135194c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov "The Delta should always be zero or negative"); 135216c29b5f285f375be53dabaa73e3e91107485fe4Anton Korobeynikov const TargetFrameLowering &TFI = *MF.getTarget().getFrameLowering(); 135394c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov 135494c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov // Create a frame entry for the EBP register that must be saved. 135594c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov int FrameIdx = MFI->CreateFixedObject(SlotSize, 135694c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov -(int)SlotSize + 135794c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov TFI.getOffsetOfLocalArea() + 135894c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov TailCallReturnAddrDelta, 135994c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov true); 136094c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov assert(FrameIdx == MFI->getObjectIndexBegin() && 136194c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov "Slot for EBP register must be last in order to be found!"); 136217001ce25cc205ac1cd2604492c2bce310964220Duncan Sands (void)FrameIdx; 136394c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov } 13643f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier 13653f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier // Spill the BasePtr if it's used. 13663f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier if (RegInfo->hasBasePointer(MF)) 13673f0dbab963197cadb32f70e1ee1a106fe35f5c8eChad Rosier MF.getRegInfo().setPhysRegUsed(RegInfo->getBaseRegister()); 136894c5ae08750f314bc3cf1bf882b686244a3927d9Anton Korobeynikov} 136976927d758657b3a511c73467ec5a7288795c1513Rafael Espindola 137076927d758657b3a511c73467ec5a7288795c1513Rafael Espindolastatic bool 137176927d758657b3a511c73467ec5a7288795c1513Rafael EspindolaHasNestArgument(const MachineFunction *MF) { 137276927d758657b3a511c73467ec5a7288795c1513Rafael Espindola const Function *F = MF->getFunction(); 137376927d758657b3a511c73467ec5a7288795c1513Rafael Espindola for (Function::const_arg_iterator I = F->arg_begin(), E = F->arg_end(); 137476927d758657b3a511c73467ec5a7288795c1513Rafael Espindola I != E; I++) { 137576927d758657b3a511c73467ec5a7288795c1513Rafael Espindola if (I->hasNestAttr()) 137676927d758657b3a511c73467ec5a7288795c1513Rafael Espindola return true; 137776927d758657b3a511c73467ec5a7288795c1513Rafael Espindola } 137876927d758657b3a511c73467ec5a7288795c1513Rafael Espindola return false; 137976927d758657b3a511c73467ec5a7288795c1513Rafael Espindola} 138076927d758657b3a511c73467ec5a7288795c1513Rafael Espindola 138198fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer/// GetScratchRegister - Get a temp register for performing work in the 138298fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer/// segmented stack and the Erlang/HiPE stack prologue. Depending on platform 138398fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer/// and the properties of the function either one or two registers will be 138498fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer/// needed. Set primary to true for the first register, false for the second. 138576927d758657b3a511c73467ec5a7288795c1513Rafael Espindolastatic unsigned 13862028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael EspindolaGetScratchRegister(bool Is64Bit, const MachineFunction &MF, bool Primary) { 138798fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer CallingConv::ID CallingConvention = MF.getFunction()->getCallingConv(); 138898fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer 138998fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer // Erlang stuff. 139098fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer if (CallingConvention == CallingConv::HiPE) { 139198fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer if (Is64Bit) 139298fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer return Primary ? X86::R14 : X86::R13; 139398fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer else 139498fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer return Primary ? X86::EBX : X86::EDI; 139598fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer } 139698fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer 13974d6ccb5f68cd7c6418a209f1fa4dbade569e4493David Blaikie if (Is64Bit) 13982028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola return Primary ? X86::R11 : X86::R12; 13994d6ccb5f68cd7c6418a209f1fa4dbade569e4493David Blaikie 14004d6ccb5f68cd7c6418a209f1fa4dbade569e4493David Blaikie bool IsNested = HasNestArgument(&MF); 14014d6ccb5f68cd7c6418a209f1fa4dbade569e4493David Blaikie 14024d6ccb5f68cd7c6418a209f1fa4dbade569e4493David Blaikie if (CallingConvention == CallingConv::X86_FastCall || 14034d6ccb5f68cd7c6418a209f1fa4dbade569e4493David Blaikie CallingConvention == CallingConv::Fast) { 14044d6ccb5f68cd7c6418a209f1fa4dbade569e4493David Blaikie if (IsNested) 14054d6ccb5f68cd7c6418a209f1fa4dbade569e4493David Blaikie report_fatal_error("Segmented stacks does not support fastcall with " 14064d6ccb5f68cd7c6418a209f1fa4dbade569e4493David Blaikie "nested function."); 14074d6ccb5f68cd7c6418a209f1fa4dbade569e4493David Blaikie return Primary ? X86::EAX : X86::ECX; 140876927d758657b3a511c73467ec5a7288795c1513Rafael Espindola } 14094d6ccb5f68cd7c6418a209f1fa4dbade569e4493David Blaikie if (IsNested) 14104d6ccb5f68cd7c6418a209f1fa4dbade569e4493David Blaikie return Primary ? X86::EDX : X86::EAX; 14114d6ccb5f68cd7c6418a209f1fa4dbade569e4493David Blaikie return Primary ? X86::ECX : X86::EAX; 141276927d758657b3a511c73467ec5a7288795c1513Rafael Espindola} 141376927d758657b3a511c73467ec5a7288795c1513Rafael Espindola 1414199ce33b3bfa0b6293946c1b835da2a1fbc8cab4Sanjoy Das// The stack limit in the TCB is set to this many bytes above the actual stack 1415199ce33b3bfa0b6293946c1b835da2a1fbc8cab4Sanjoy Das// limit. 1416199ce33b3bfa0b6293946c1b835da2a1fbc8cab4Sanjoy Dasstatic const uint64_t kSplitStackAvailable = 256; 1417199ce33b3bfa0b6293946c1b835da2a1fbc8cab4Sanjoy Das 141876927d758657b3a511c73467ec5a7288795c1513Rafael Espindolavoid 141976927d758657b3a511c73467ec5a7288795c1513Rafael EspindolaX86FrameLowering::adjustForSegmentedStacks(MachineFunction &MF) const { 142076927d758657b3a511c73467ec5a7288795c1513Rafael Espindola MachineBasicBlock &prologueMBB = MF.front(); 142176927d758657b3a511c73467ec5a7288795c1513Rafael Espindola MachineFrameInfo *MFI = MF.getFrameInfo(); 142276927d758657b3a511c73467ec5a7288795c1513Rafael Espindola const X86InstrInfo &TII = *TM.getInstrInfo(); 142376927d758657b3a511c73467ec5a7288795c1513Rafael Espindola uint64_t StackSize; 142476927d758657b3a511c73467ec5a7288795c1513Rafael Espindola bool Is64Bit = STI.is64Bit(); 142576927d758657b3a511c73467ec5a7288795c1513Rafael Espindola unsigned TlsReg, TlsOffset; 142676927d758657b3a511c73467ec5a7288795c1513Rafael Espindola DebugLoc DL; 142776927d758657b3a511c73467ec5a7288795c1513Rafael Espindola 14282028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola unsigned ScratchReg = GetScratchRegister(Is64Bit, MF, true); 142976927d758657b3a511c73467ec5a7288795c1513Rafael Espindola assert(!MF.getRegInfo().isLiveIn(ScratchReg) && 143076927d758657b3a511c73467ec5a7288795c1513Rafael Espindola "Scratch register is live-in"); 143176927d758657b3a511c73467ec5a7288795c1513Rafael Espindola 143276927d758657b3a511c73467ec5a7288795c1513Rafael Espindola if (MF.getFunction()->isVarArg()) 143376927d758657b3a511c73467ec5a7288795c1513Rafael Espindola report_fatal_error("Segmented stacks do not support vararg functions."); 1434b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer if (!STI.isTargetLinux() && !STI.isTargetDarwin() && 1435b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer !STI.isTargetWin32() && !STI.isTargetFreeBSD()) 143685b9d43d4c7a4a5e6e7da651a159353a9a00e227Rafael Espindola report_fatal_error("Segmented stacks not supported on this platform."); 143776927d758657b3a511c73467ec5a7288795c1513Rafael Espindola 143876927d758657b3a511c73467ec5a7288795c1513Rafael Espindola MachineBasicBlock *allocMBB = MF.CreateMachineBasicBlock(); 143976927d758657b3a511c73467ec5a7288795c1513Rafael Espindola MachineBasicBlock *checkMBB = MF.CreateMachineBasicBlock(); 144076927d758657b3a511c73467ec5a7288795c1513Rafael Espindola X86MachineFunctionInfo *X86FI = MF.getInfo<X86MachineFunctionInfo>(); 144176927d758657b3a511c73467ec5a7288795c1513Rafael Espindola bool IsNested = false; 144276927d758657b3a511c73467ec5a7288795c1513Rafael Espindola 144376927d758657b3a511c73467ec5a7288795c1513Rafael Espindola // We need to know if the function has a nest argument only in 64 bit mode. 144476927d758657b3a511c73467ec5a7288795c1513Rafael Espindola if (Is64Bit) 144576927d758657b3a511c73467ec5a7288795c1513Rafael Espindola IsNested = HasNestArgument(&MF); 144676927d758657b3a511c73467ec5a7288795c1513Rafael Espindola 14474e68054b20725f6ec1cac33630258f749fe5debeBill Wendling // The MOV R10, RAX needs to be in a different block, since the RET we emit in 14484e68054b20725f6ec1cac33630258f749fe5debeBill Wendling // allocMBB needs to be last (terminating) instruction. 14494e68054b20725f6ec1cac33630258f749fe5debeBill Wendling 145076927d758657b3a511c73467ec5a7288795c1513Rafael Espindola for (MachineBasicBlock::livein_iterator i = prologueMBB.livein_begin(), 145176927d758657b3a511c73467ec5a7288795c1513Rafael Espindola e = prologueMBB.livein_end(); i != e; i++) { 145276927d758657b3a511c73467ec5a7288795c1513Rafael Espindola allocMBB->addLiveIn(*i); 145376927d758657b3a511c73467ec5a7288795c1513Rafael Espindola checkMBB->addLiveIn(*i); 145476927d758657b3a511c73467ec5a7288795c1513Rafael Espindola } 145576927d758657b3a511c73467ec5a7288795c1513Rafael Espindola 1456e840e88239cf92a065cbf5f5b9c7d18bc139c0e1Rafael Espindola if (IsNested) 145776927d758657b3a511c73467ec5a7288795c1513Rafael Espindola allocMBB->addLiveIn(X86::R10); 145876927d758657b3a511c73467ec5a7288795c1513Rafael Espindola 145976927d758657b3a511c73467ec5a7288795c1513Rafael Espindola MF.push_front(allocMBB); 146076927d758657b3a511c73467ec5a7288795c1513Rafael Espindola MF.push_front(checkMBB); 146176927d758657b3a511c73467ec5a7288795c1513Rafael Espindola 146276927d758657b3a511c73467ec5a7288795c1513Rafael Espindola // Eventually StackSize will be calculated by a link-time pass; which will 146376927d758657b3a511c73467ec5a7288795c1513Rafael Espindola // also decide whether checking code needs to be injected into this particular 146476927d758657b3a511c73467ec5a7288795c1513Rafael Espindola // prologue. 146576927d758657b3a511c73467ec5a7288795c1513Rafael Espindola StackSize = MFI->getStackSize(); 146676927d758657b3a511c73467ec5a7288795c1513Rafael Espindola 14672028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola // When the frame size is less than 256 we just compare the stack 14682028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola // boundary directly to the value of the stack pointer, per gcc. 14692028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola bool CompareStackPointer = StackSize < kSplitStackAvailable; 14702028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola 147176927d758657b3a511c73467ec5a7288795c1513Rafael Espindola // Read the limit off the current stacklet off the stack_guard location. 147276927d758657b3a511c73467ec5a7288795c1513Rafael Espindola if (Is64Bit) { 1473b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer if (STI.isTargetLinux()) { 14742028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola TlsReg = X86::FS; 14752028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola TlsOffset = 0x70; 1476b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer } else if (STI.isTargetDarwin()) { 14772028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola TlsReg = X86::GS; 14782028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola TlsOffset = 0x60 + 90*8; // See pthread_machdep.h. Steal TLS slot 90. 1479b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer } else if (STI.isTargetFreeBSD()) { 148085b9d43d4c7a4a5e6e7da651a159353a9a00e227Rafael Espindola TlsReg = X86::FS; 148185b9d43d4c7a4a5e6e7da651a159353a9a00e227Rafael Espindola TlsOffset = 0x18; 1482e4d18de5d15c6c1d4d279788b35d0cd1ab237e82Rafael Espindola } else { 1483e4d18de5d15c6c1d4d279788b35d0cd1ab237e82Rafael Espindola report_fatal_error("Segmented stacks not supported on this platform."); 14842028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola } 148576927d758657b3a511c73467ec5a7288795c1513Rafael Espindola 14862028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola if (CompareStackPointer) 1487199ce33b3bfa0b6293946c1b835da2a1fbc8cab4Sanjoy Das ScratchReg = X86::RSP; 1488199ce33b3bfa0b6293946c1b835da2a1fbc8cab4Sanjoy Das else 1489199ce33b3bfa0b6293946c1b835da2a1fbc8cab4Sanjoy Das BuildMI(checkMBB, DL, TII.get(X86::LEA64r), ScratchReg).addReg(X86::RSP) 1490014f7a3b3798580d5aac80b83bcb67e03d302fa4Rafael Espindola .addImm(1).addReg(0).addImm(-StackSize).addReg(0); 1491199ce33b3bfa0b6293946c1b835da2a1fbc8cab4Sanjoy Das 149276927d758657b3a511c73467ec5a7288795c1513Rafael Espindola BuildMI(checkMBB, DL, TII.get(X86::CMP64rm)).addReg(ScratchReg) 1493014f7a3b3798580d5aac80b83bcb67e03d302fa4Rafael Espindola .addReg(0).addImm(1).addReg(0).addImm(TlsOffset).addReg(TlsReg); 149476927d758657b3a511c73467ec5a7288795c1513Rafael Espindola } else { 1495b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer if (STI.isTargetLinux()) { 1496e4d18de5d15c6c1d4d279788b35d0cd1ab237e82Rafael Espindola TlsReg = X86::GS; 1497e4d18de5d15c6c1d4d279788b35d0cd1ab237e82Rafael Espindola TlsOffset = 0x30; 1498b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer } else if (STI.isTargetDarwin()) { 1499e4d18de5d15c6c1d4d279788b35d0cd1ab237e82Rafael Espindola TlsReg = X86::GS; 1500e4d18de5d15c6c1d4d279788b35d0cd1ab237e82Rafael Espindola TlsOffset = 0x48 + 90*4; 1501b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer } else if (STI.isTargetWin32()) { 1502e4d18de5d15c6c1d4d279788b35d0cd1ab237e82Rafael Espindola TlsReg = X86::FS; 1503e4d18de5d15c6c1d4d279788b35d0cd1ab237e82Rafael Espindola TlsOffset = 0x14; // pvArbitrary, reserved for application use 1504b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer } else if (STI.isTargetFreeBSD()) { 150585b9d43d4c7a4a5e6e7da651a159353a9a00e227Rafael Espindola report_fatal_error("Segmented stacks not supported on FreeBSD i386."); 1506e4d18de5d15c6c1d4d279788b35d0cd1ab237e82Rafael Espindola } else { 1507e4d18de5d15c6c1d4d279788b35d0cd1ab237e82Rafael Espindola report_fatal_error("Segmented stacks not supported on this platform."); 1508e4d18de5d15c6c1d4d279788b35d0cd1ab237e82Rafael Espindola } 150976927d758657b3a511c73467ec5a7288795c1513Rafael Espindola 15102028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola if (CompareStackPointer) 1511199ce33b3bfa0b6293946c1b835da2a1fbc8cab4Sanjoy Das ScratchReg = X86::ESP; 1512199ce33b3bfa0b6293946c1b835da2a1fbc8cab4Sanjoy Das else 1513199ce33b3bfa0b6293946c1b835da2a1fbc8cab4Sanjoy Das BuildMI(checkMBB, DL, TII.get(X86::LEA32r), ScratchReg).addReg(X86::ESP) 1514014f7a3b3798580d5aac80b83bcb67e03d302fa4Rafael Espindola .addImm(1).addReg(0).addImm(-StackSize).addReg(0); 1515199ce33b3bfa0b6293946c1b835da2a1fbc8cab4Sanjoy Das 1516b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer if (STI.isTargetLinux() || STI.isTargetWin32()) { 15172028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola BuildMI(checkMBB, DL, TII.get(X86::CMP32rm)).addReg(ScratchReg) 15182028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola .addReg(0).addImm(0).addReg(0).addImm(TlsOffset).addReg(TlsReg); 1519b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer } else if (STI.isTargetDarwin()) { 15202028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola 15212028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola // TlsOffset doesn't fit into a mod r/m byte so we need an extra register 15222028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola unsigned ScratchReg2; 15232028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola bool SaveScratch2; 15242028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola if (CompareStackPointer) { 15252028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola // The primary scratch register is available for holding the TLS offset 15262028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola ScratchReg2 = GetScratchRegister(Is64Bit, MF, true); 15272028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola SaveScratch2 = false; 15282028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola } else { 15292028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola // Need to use a second register to hold the TLS offset 15302028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola ScratchReg2 = GetScratchRegister(Is64Bit, MF, false); 15312028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola 15322028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola // Unfortunately, with fastcc the second scratch register may hold an arg 15332028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola SaveScratch2 = MF.getRegInfo().isLiveIn(ScratchReg2); 15342028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola } 15352028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola 15362028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola // If Scratch2 is live-in then it needs to be saved 15372028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola assert((!MF.getRegInfo().isLiveIn(ScratchReg2) || SaveScratch2) && 15382028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola "Scratch register is live-in and not saved"); 15392028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola 15402028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola if (SaveScratch2) 15412028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola BuildMI(checkMBB, DL, TII.get(X86::PUSH32r)) 15422028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola .addReg(ScratchReg2, RegState::Kill); 15432028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola 15442028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola BuildMI(checkMBB, DL, TII.get(X86::MOV32ri), ScratchReg2) 15452028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola .addImm(TlsOffset); 15462028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola BuildMI(checkMBB, DL, TII.get(X86::CMP32rm)) 15472028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola .addReg(ScratchReg) 15482028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola .addReg(ScratchReg2).addImm(1).addReg(0) 15492028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola .addImm(0) 15502028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola .addReg(TlsReg); 15512028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola 15522028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola if (SaveScratch2) 15532028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola BuildMI(checkMBB, DL, TII.get(X86::POP32r), ScratchReg2); 15542028b793e1fd1a8dd4d99b0b7c9972865d5e806aRafael Espindola } 155576927d758657b3a511c73467ec5a7288795c1513Rafael Espindola } 155676927d758657b3a511c73467ec5a7288795c1513Rafael Espindola 155776927d758657b3a511c73467ec5a7288795c1513Rafael Espindola // This jump is taken if SP >= (Stacklet Limit + Stack Space required). 155876927d758657b3a511c73467ec5a7288795c1513Rafael Espindola // It jumps to normal execution of the function body. 1559313c7038319422cff0b2ea1015e180575cab4b7aRafael Espindola BuildMI(checkMBB, DL, TII.get(X86::JA_4)).addMBB(&prologueMBB); 156076927d758657b3a511c73467ec5a7288795c1513Rafael Espindola 156176927d758657b3a511c73467ec5a7288795c1513Rafael Espindola // On 32 bit we first push the arguments size and then the frame size. On 64 156276927d758657b3a511c73467ec5a7288795c1513Rafael Espindola // bit, we pass the stack frame size in r10 and the argument size in r11. 156376927d758657b3a511c73467ec5a7288795c1513Rafael Espindola if (Is64Bit) { 156476927d758657b3a511c73467ec5a7288795c1513Rafael Espindola // Functions with nested arguments use R10, so it needs to be saved across 156576927d758657b3a511c73467ec5a7288795c1513Rafael Espindola // the call to _morestack 156676927d758657b3a511c73467ec5a7288795c1513Rafael Espindola 156776927d758657b3a511c73467ec5a7288795c1513Rafael Espindola if (IsNested) 156876927d758657b3a511c73467ec5a7288795c1513Rafael Espindola BuildMI(allocMBB, DL, TII.get(X86::MOV64rr), X86::RAX).addReg(X86::R10); 156976927d758657b3a511c73467ec5a7288795c1513Rafael Espindola 157076927d758657b3a511c73467ec5a7288795c1513Rafael Espindola BuildMI(allocMBB, DL, TII.get(X86::MOV64ri), X86::R10) 157176927d758657b3a511c73467ec5a7288795c1513Rafael Espindola .addImm(StackSize); 157276927d758657b3a511c73467ec5a7288795c1513Rafael Espindola BuildMI(allocMBB, DL, TII.get(X86::MOV64ri), X86::R11) 157376927d758657b3a511c73467ec5a7288795c1513Rafael Espindola .addImm(X86FI->getArgumentStackSize()); 157476927d758657b3a511c73467ec5a7288795c1513Rafael Espindola MF.getRegInfo().setPhysRegUsed(X86::R10); 157576927d758657b3a511c73467ec5a7288795c1513Rafael Espindola MF.getRegInfo().setPhysRegUsed(X86::R11); 157676927d758657b3a511c73467ec5a7288795c1513Rafael Espindola } else { 157776927d758657b3a511c73467ec5a7288795c1513Rafael Espindola BuildMI(allocMBB, DL, TII.get(X86::PUSHi32)) 157876927d758657b3a511c73467ec5a7288795c1513Rafael Espindola .addImm(X86FI->getArgumentStackSize()); 157976927d758657b3a511c73467ec5a7288795c1513Rafael Espindola BuildMI(allocMBB, DL, TII.get(X86::PUSHi32)) 158076927d758657b3a511c73467ec5a7288795c1513Rafael Espindola .addImm(StackSize); 158176927d758657b3a511c73467ec5a7288795c1513Rafael Espindola } 158276927d758657b3a511c73467ec5a7288795c1513Rafael Espindola 158376927d758657b3a511c73467ec5a7288795c1513Rafael Espindola // __morestack is in libgcc 158476927d758657b3a511c73467ec5a7288795c1513Rafael Espindola if (Is64Bit) 158576927d758657b3a511c73467ec5a7288795c1513Rafael Espindola BuildMI(allocMBB, DL, TII.get(X86::CALL64pcrel32)) 158676927d758657b3a511c73467ec5a7288795c1513Rafael Espindola .addExternalSymbol("__morestack"); 158776927d758657b3a511c73467ec5a7288795c1513Rafael Espindola else 158876927d758657b3a511c73467ec5a7288795c1513Rafael Espindola BuildMI(allocMBB, DL, TII.get(X86::CALLpcrel32)) 158976927d758657b3a511c73467ec5a7288795c1513Rafael Espindola .addExternalSymbol("__morestack"); 159076927d758657b3a511c73467ec5a7288795c1513Rafael Espindola 15914e68054b20725f6ec1cac33630258f749fe5debeBill Wendling if (IsNested) 1592e840e88239cf92a065cbf5f5b9c7d18bc139c0e1Rafael Espindola BuildMI(allocMBB, DL, TII.get(X86::MORESTACK_RET_RESTORE_R10)); 1593e840e88239cf92a065cbf5f5b9c7d18bc139c0e1Rafael Espindola else 1594e840e88239cf92a065cbf5f5b9c7d18bc139c0e1Rafael Espindola BuildMI(allocMBB, DL, TII.get(X86::MORESTACK_RET)); 159576927d758657b3a511c73467ec5a7288795c1513Rafael Espindola 1596e840e88239cf92a065cbf5f5b9c7d18bc139c0e1Rafael Espindola allocMBB->addSuccessor(&prologueMBB); 159782222c20be24adda7c218f3fdaf2e0ae049c955bBill Wendling 159876927d758657b3a511c73467ec5a7288795c1513Rafael Espindola checkMBB->addSuccessor(allocMBB); 159976927d758657b3a511c73467ec5a7288795c1513Rafael Espindola checkMBB->addSuccessor(&prologueMBB); 160076927d758657b3a511c73467ec5a7288795c1513Rafael Espindola 160151f0c7641983469cbd29f8862a121645471a885aJakob Stoklund Olesen#ifdef XDEBUG 160276927d758657b3a511c73467ec5a7288795c1513Rafael Espindola MF.verify(); 160376927d758657b3a511c73467ec5a7288795c1513Rafael Espindola#endif 160476927d758657b3a511c73467ec5a7288795c1513Rafael Espindola} 160598fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer 16062d1035def15030ae404b227747d0a28454ea32a9Yiannis Tsiouris/// Erlang programs may need a special prologue to handle the stack size they 16072d1035def15030ae404b227747d0a28454ea32a9Yiannis Tsiouris/// might need at runtime. That is because Erlang/OTP does not implement a C 16082d1035def15030ae404b227747d0a28454ea32a9Yiannis Tsiouris/// stack but uses a custom implementation of hybrid stack/heap architecture. 16092d1035def15030ae404b227747d0a28454ea32a9Yiannis Tsiouris/// (for more information see Eric Stenman's Ph.D. thesis: 16102d1035def15030ae404b227747d0a28454ea32a9Yiannis Tsiouris/// http://publications.uu.se/uu/fulltext/nbn_se_uu_diva-2688.pdf) 16112d1035def15030ae404b227747d0a28454ea32a9Yiannis Tsiouris/// 16122d1035def15030ae404b227747d0a28454ea32a9Yiannis Tsiouris/// CheckStack: 16132d1035def15030ae404b227747d0a28454ea32a9Yiannis Tsiouris/// temp0 = sp - MaxStack 16142d1035def15030ae404b227747d0a28454ea32a9Yiannis Tsiouris/// if( temp0 < SP_LIMIT(P) ) goto IncStack else goto OldStart 16152d1035def15030ae404b227747d0a28454ea32a9Yiannis Tsiouris/// OldStart: 16162d1035def15030ae404b227747d0a28454ea32a9Yiannis Tsiouris/// ... 16172d1035def15030ae404b227747d0a28454ea32a9Yiannis Tsiouris/// IncStack: 16182d1035def15030ae404b227747d0a28454ea32a9Yiannis Tsiouris/// call inc_stack # doubles the stack space 16192d1035def15030ae404b227747d0a28454ea32a9Yiannis Tsiouris/// temp0 = sp - MaxStack 16202d1035def15030ae404b227747d0a28454ea32a9Yiannis Tsiouris/// if( temp0 < SP_LIMIT(P) ) goto IncStack else goto OldStart 162198fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramervoid X86FrameLowering::adjustForHiPEPrologue(MachineFunction &MF) const { 162298fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer const X86InstrInfo &TII = *TM.getInstrInfo(); 162398fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer MachineFrameInfo *MFI = MF.getFrameInfo(); 1624b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer const unsigned SlotSize = TM.getRegisterInfo()->getSlotSize(); 162598fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer const bool Is64Bit = STI.is64Bit(); 162698fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer DebugLoc DL; 162798fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer // HiPE-specific values 162898fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer const unsigned HipeLeafWords = 24; 162998fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer const unsigned CCRegisteredArgs = Is64Bit ? 6 : 5; 163098fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer const unsigned Guaranteed = HipeLeafWords * SlotSize; 1631b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer unsigned CallerStkArity = MF.getFunction()->arg_size() > CCRegisteredArgs ? 1632b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer MF.getFunction()->arg_size() - CCRegisteredArgs : 0; 1633b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer unsigned MaxStack = MFI->getStackSize() + CallerStkArity*SlotSize + SlotSize; 163498fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer 1635b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer assert(STI.isTargetLinux() && 163698fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer "HiPE prologue is only supported on Linux operating systems."); 163798fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer 163898fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer // Compute the largest caller's frame that is needed to fit the callees' 163998fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer // frames. This 'MaxStack' is computed from: 164098fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer // 164198fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer // a) the fixed frame size, which is the space needed for all spilled temps, 164298fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer // b) outgoing on-stack parameter areas, and 164398fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer // c) the minimum stack space this function needs to make available for the 164498fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer // functions it calls (a tunable ABI property). 164598fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer if (MFI->hasCalls()) { 164698fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer unsigned MoreStackForCalls = 0; 164798fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer 164898fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer for (MachineFunction::iterator MBBI = MF.begin(), MBBE = MF.end(); 164998fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer MBBI != MBBE; ++MBBI) 165098fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer for (MachineBasicBlock::iterator MI = MBBI->begin(), ME = MBBI->end(); 1651b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer MI != ME; ++MI) { 1652b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer if (!MI->isCall()) 1653b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer continue; 1654b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer 1655b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer // Get callee operand. 1656b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer const MachineOperand &MO = MI->getOperand(0); 1657b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer 1658b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer // Only take account of global function calls (no closures etc.). 1659b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer if (!MO.isGlobal()) 1660b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer continue; 1661b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer 1662b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer const Function *F = dyn_cast<Function>(MO.getGlobal()); 1663b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer if (!F) 1664b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer continue; 1665b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer 1666b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer // Do not update 'MaxStack' for primitive and built-in functions 1667b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer // (encoded with names either starting with "erlang."/"bif_" or not 1668b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer // having a ".", such as a simple <Module>.<Function>.<Arity>, or an 1669b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer // "_", such as the BIF "suspend_0") as they are executed on another 1670b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer // stack. 1671b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer if (F->getName().find("erlang.") != StringRef::npos || 1672b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer F->getName().find("bif_") != StringRef::npos || 1673b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer F->getName().find_first_of("._") == StringRef::npos) 1674b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer continue; 1675b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer 1676b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer unsigned CalleeStkArity = 1677b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer F->arg_size() > CCRegisteredArgs ? F->arg_size()-CCRegisteredArgs : 0; 1678b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer if (HipeLeafWords - 1 > CalleeStkArity) 1679b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer MoreStackForCalls = std::max(MoreStackForCalls, 1680b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer (HipeLeafWords - 1 - CalleeStkArity) * SlotSize); 1681b1e1d5d4a575f5e5b4ceb7af68f33e75695ee959Benjamin Kramer } 168298fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer MaxStack += MoreStackForCalls; 168398fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer } 168498fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer 168598fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer // If the stack frame needed is larger than the guaranteed then runtime checks 168698fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer // and calls to "inc_stack_0" BIF should be inserted in the assembly prologue. 168798fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer if (MaxStack > Guaranteed) { 168898fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer MachineBasicBlock &prologueMBB = MF.front(); 168998fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer MachineBasicBlock *stackCheckMBB = MF.CreateMachineBasicBlock(); 169098fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer MachineBasicBlock *incStackMBB = MF.CreateMachineBasicBlock(); 169198fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer 169298fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer for (MachineBasicBlock::livein_iterator I = prologueMBB.livein_begin(), 169398fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer E = prologueMBB.livein_end(); I != E; I++) { 169498fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer stackCheckMBB->addLiveIn(*I); 169598fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer incStackMBB->addLiveIn(*I); 169698fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer } 169798fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer 169898fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer MF.push_front(incStackMBB); 169998fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer MF.push_front(stackCheckMBB); 170098fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer 170198fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer unsigned ScratchReg, SPReg, PReg, SPLimitOffset; 170298fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer unsigned LEAop, CMPop, CALLop; 170398fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer if (Is64Bit) { 170498fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer SPReg = X86::RSP; 170598fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer PReg = X86::RBP; 170698fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer LEAop = X86::LEA64r; 170798fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer CMPop = X86::CMP64rm; 170898fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer CALLop = X86::CALL64pcrel32; 170998fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer SPLimitOffset = 0x90; 171098fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer } else { 171198fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer SPReg = X86::ESP; 171298fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer PReg = X86::EBP; 171398fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer LEAop = X86::LEA32r; 171498fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer CMPop = X86::CMP32rm; 171598fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer CALLop = X86::CALLpcrel32; 171698fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer SPLimitOffset = 0x4c; 171798fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer } 171898fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer 171998fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer ScratchReg = GetScratchRegister(Is64Bit, MF, true); 172098fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer assert(!MF.getRegInfo().isLiveIn(ScratchReg) && 172198fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer "HiPE prologue scratch register is live-in"); 172298fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer 172398fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer // Create new MBB for StackCheck: 172498fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer addRegOffset(BuildMI(stackCheckMBB, DL, TII.get(LEAop), ScratchReg), 172598fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer SPReg, false, -MaxStack); 172698fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer // SPLimitOffset is in a fixed heap location (pointed by BP). 172798fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer addRegOffset(BuildMI(stackCheckMBB, DL, TII.get(CMPop)) 172898fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer .addReg(ScratchReg), PReg, false, SPLimitOffset); 172998fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer BuildMI(stackCheckMBB, DL, TII.get(X86::JAE_4)).addMBB(&prologueMBB); 173098fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer 173198fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer // Create new MBB for IncStack: 173298fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer BuildMI(incStackMBB, DL, TII.get(CALLop)). 173398fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer addExternalSymbol("inc_stack_0"); 173498fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer addRegOffset(BuildMI(incStackMBB, DL, TII.get(LEAop), ScratchReg), 173598fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer SPReg, false, -MaxStack); 173698fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer addRegOffset(BuildMI(incStackMBB, DL, TII.get(CMPop)) 173798fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer .addReg(ScratchReg), PReg, false, SPLimitOffset); 173898fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer BuildMI(incStackMBB, DL, TII.get(X86::JLE_4)).addMBB(incStackMBB); 173998fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer 174098fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer stackCheckMBB->addSuccessor(&prologueMBB, 99); 174198fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer stackCheckMBB->addSuccessor(incStackMBB, 1); 174298fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer incStackMBB->addSuccessor(&prologueMBB, 99); 174398fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer incStackMBB->addSuccessor(incStackMBB, 1); 174498fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer } 174598fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer#ifdef XDEBUG 174698fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer MF.verify(); 174798fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer#endif 174898fbe27ac8f0766ea94b89b8c03418131b72bea4Benjamin Kramer} 1749700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky 1750700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Benderskyvoid X86FrameLowering:: 1751700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli BenderskyeliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB, 1752700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky MachineBasicBlock::iterator I) const { 1753700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky const X86InstrInfo &TII = *TM.getInstrInfo(); 1754700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky const X86RegisterInfo &RegInfo = *TM.getRegisterInfo(); 1755700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky unsigned StackPtr = RegInfo.getStackRegister(); 1756700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky bool reseveCallFrame = hasReservedCallFrame(MF); 1757700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky int Opcode = I->getOpcode(); 1758700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky bool isDestroy = Opcode == TII.getCallFrameDestroyOpcode(); 1759700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky bool IsLP64 = STI.isTarget64BitLP64(); 1760700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky DebugLoc DL = I->getDebugLoc(); 1761700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky uint64_t Amount = !reseveCallFrame ? I->getOperand(0).getImm() : 0; 1762700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky uint64_t CalleeAmt = isDestroy ? I->getOperand(1).getImm() : 0; 1763700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky I = MBB.erase(I); 1764700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky 1765700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky if (!reseveCallFrame) { 1766700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky // If the stack pointer can be changed after prologue, turn the 1767700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky // adjcallstackup instruction into a 'sub ESP, <amt>' and the 1768700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky // adjcallstackdown instruction into 'add ESP, <amt>' 1769700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky // TODO: consider using push / pop instead of sub + store / add 1770700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky if (Amount == 0) 1771700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky return; 1772700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky 1773700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky // We need to keep the stack aligned properly. To do this, we round the 1774700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky // amount of space needed for the outgoing arguments up to the next 1775700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky // alignment boundary. 1776700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky unsigned StackAlign = TM.getFrameLowering()->getStackAlignment(); 1777700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky Amount = (Amount + StackAlign - 1) / StackAlign * StackAlign; 1778700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky 1779700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky MachineInstr *New = 0; 1780700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky if (Opcode == TII.getCallFrameSetupOpcode()) { 1781700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky New = BuildMI(MF, DL, TII.get(getSUBriOpcode(IsLP64, Amount)), 1782700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky StackPtr) 1783700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky .addReg(StackPtr) 1784700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky .addImm(Amount); 1785700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky } else { 1786700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky assert(Opcode == TII.getCallFrameDestroyOpcode()); 1787700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky 1788700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky // Factor out the amount the callee already popped. 1789700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky Amount -= CalleeAmt; 1790700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky 1791700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky if (Amount) { 1792700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky unsigned Opc = getADDriOpcode(IsLP64, Amount); 1793700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky New = BuildMI(MF, DL, TII.get(Opc), StackPtr) 1794700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky .addReg(StackPtr).addImm(Amount); 1795700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky } 1796700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky } 1797700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky 1798700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky if (New) { 1799700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky // The EFLAGS implicit def is dead. 1800700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky New->getOperand(3).setIsDead(); 1801700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky 1802700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky // Replace the pseudo instruction with a new instruction. 1803700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky MBB.insert(I, New); 1804700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky } 1805700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky 1806700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky return; 1807700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky } 1808700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky 1809700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky if (Opcode == TII.getCallFrameDestroyOpcode() && CalleeAmt) { 1810700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky // If we are performing frame pointer elimination and if the callee pops 1811700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky // something off the stack pointer, add it back. We do this until we have 1812700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky // more advanced stack pointer tracking ability. 1813700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky unsigned Opc = getSUBriOpcode(IsLP64, CalleeAmt); 1814700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky MachineInstr *New = BuildMI(MF, DL, TII.get(Opc), StackPtr) 1815700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky .addReg(StackPtr).addImm(CalleeAmt); 1816700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky 1817700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky // The EFLAGS implicit def is dead. 1818700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky New->getOperand(3).setIsDead(); 1819700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky 1820700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky // We are not tracking the stack pointer adjustment by the callee, so make 1821700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky // sure we restore the stack pointer immediately after the call, there may 1822700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky // be spill code inserted between the CALL and ADJCALLSTACKUP instructions. 1823700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky MachineBasicBlock::iterator B = MBB.begin(); 1824700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky while (I != B && !llvm::prior(I)->isCall()) 1825700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky --I; 1826700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky MBB.insert(I, New); 1827700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky } 1828700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky} 1829700ed80d3da5e98e05ceb90e9bfb66058581a6dbEli Bendersky 1830