From 2005f26890c575658fe19de1c57b64616495d17c Mon Sep 17 00:00:00 2001 From: dim Date: Mon, 17 Aug 2020 16:37:46 +0000 Subject: [PATCH] Merge commit 4d52ebb9b9c7 from llvm git (by Chen Zheng): [PowerPC] Make StartMI ignore COPY like instructions. Reviewed By: lkail Differential Revision: https://reviews.llvm.org/D85659 This fixes an assertion failure when building world for powerpc. It was reported upstream as . --- .../llvm/lib/Target/PowerPC/PPCInstrInfo.cpp | 49 ++++++++++++------- .../llvm/lib/Target/PowerPC/PPCInstrInfo.h | 6 ++- 2 files changed, 35 insertions(+), 20 deletions(-) diff --git a/contrib/llvm-project/llvm/lib/Target/PowerPC/PPCInstrInfo.cpp b/contrib/llvm-project/llvm/lib/Target/PowerPC/PPCInstrInfo.cpp index 9a4c57fedac2..e428e7155e5e 100644 --- a/contrib/llvm-project/llvm/lib/Target/PowerPC/PPCInstrInfo.cpp +++ b/contrib/llvm-project/llvm/lib/Target/PowerPC/PPCInstrInfo.cpp @@ -2653,22 +2653,35 @@ const unsigned *PPCInstrInfo::getLoadOpcodesForSpillArray() const { return LoadSpillOpcodesArray[getSpillTarget()]; } -void PPCInstrInfo::fixupIsDeadOrKill(MachineInstr &StartMI, MachineInstr &EndMI, +void PPCInstrInfo::fixupIsDeadOrKill(MachineInstr *StartMI, MachineInstr *EndMI, unsigned RegNo) const { // Conservatively clear kill flag for the register if the instructions are in // different basic blocks and in SSA form, because the kill flag may no longer // be right. There is no need to bother with dead flags since defs with no // uses will be handled by DCE. - MachineRegisterInfo &MRI = StartMI.getParent()->getParent()->getRegInfo(); - if (MRI.isSSA() && (StartMI.getParent() != EndMI.getParent())) { + MachineRegisterInfo &MRI = StartMI->getParent()->getParent()->getRegInfo(); + if (MRI.isSSA() && (StartMI->getParent() != EndMI->getParent())) { MRI.clearKillFlags(RegNo); return; } // Instructions between [StartMI, EndMI] should be in same basic block. - assert((StartMI.getParent() == EndMI.getParent()) && + assert((StartMI->getParent() == EndMI->getParent()) && "Instructions are not in same basic block"); + // If before RA, StartMI may be def through COPY, we need to adjust it to the + // real def. See function getForwardingDefMI. + if (MRI.isSSA()) { + bool Reads, Writes; + std::tie(Reads, Writes) = StartMI->readsWritesVirtualRegister(RegNo); + if (!Reads && !Writes) { + assert(Register::isVirtualRegister(RegNo) && + "Must be a virtual register"); + // Get real def and ignore copies. + StartMI = MRI.getVRegDef(RegNo); + } + } + bool IsKillSet = false; auto clearOperandKillInfo = [=] (MachineInstr &MI, unsigned Index) { @@ -2681,21 +2694,21 @@ void PPCInstrInfo::fixupIsDeadOrKill(MachineInstr &StartMI, MachineInstr &EndMI, // Set killed flag for EndMI. // No need to do anything if EndMI defines RegNo. int UseIndex = - EndMI.findRegisterUseOperandIdx(RegNo, false, &getRegisterInfo()); + EndMI->findRegisterUseOperandIdx(RegNo, false, &getRegisterInfo()); if (UseIndex != -1) { - EndMI.getOperand(UseIndex).setIsKill(true); + EndMI->getOperand(UseIndex).setIsKill(true); IsKillSet = true; // Clear killed flag for other EndMI operands related to RegNo. In some // upexpected cases, killed may be set multiple times for same register // operand in same MI. - for (int i = 0, e = EndMI.getNumOperands(); i != e; ++i) + for (int i = 0, e = EndMI->getNumOperands(); i != e; ++i) if (i != UseIndex) - clearOperandKillInfo(EndMI, i); + clearOperandKillInfo(*EndMI, i); } // Walking the inst in reverse order (EndMI -> StartMI]. - MachineBasicBlock::reverse_iterator It = EndMI; - MachineBasicBlock::reverse_iterator E = EndMI.getParent()->rend(); + MachineBasicBlock::reverse_iterator It = *EndMI; + MachineBasicBlock::reverse_iterator E = EndMI->getParent()->rend(); // EndMI has been handled above, skip it here. It++; MachineOperand *MO = nullptr; @@ -2721,13 +2734,13 @@ void PPCInstrInfo::fixupIsDeadOrKill(MachineInstr &StartMI, MachineInstr &EndMI, } else if ((MO = It->findRegisterDefOperand(RegNo, false, true, &getRegisterInfo()))) { // No use found, set dead for its def. - assert(&*It == &StartMI && "No new def between StartMI and EndMI."); + assert(&*It == StartMI && "No new def between StartMI and EndMI."); MO->setIsDead(true); break; } } - if ((&*It) == &StartMI) + if ((&*It) == StartMI) break; } // Ensure RegMo liveness is killed after EndMI. @@ -3858,7 +3871,7 @@ bool PPCInstrInfo::simplifyToLI(MachineInstr &MI, MachineInstr &DefMI, // ForwardingOperandReg = LI imm1 // y = op2 imm2, ForwardingOperandReg(killed) if (IsForwardingOperandKilled) - fixupIsDeadOrKill(DefMI, MI, ForwardingOperandReg); + fixupIsDeadOrKill(&DefMI, &MI, ForwardingOperandReg); LLVM_DEBUG(dbgs() << "With:\n"); LLVM_DEBUG(MI.dump()); @@ -3950,9 +3963,9 @@ bool PPCInstrInfo::transformToNewImmFormFedByAdd( // Update kill flag if (RegMO->isKill() || IsKilledFor(RegMO->getReg())) - fixupIsDeadOrKill(DefMI, MI, RegMO->getReg()); + fixupIsDeadOrKill(&DefMI, &MI, RegMO->getReg()); if (ForwardKilledOperandReg != ~0U) - fixupIsDeadOrKill(DefMI, MI, ForwardKilledOperandReg); + fixupIsDeadOrKill(&DefMI, &MI, ForwardKilledOperandReg); } LLVM_DEBUG(dbgs() << "With:\n"); @@ -4063,12 +4076,12 @@ bool PPCInstrInfo::transformToImmFormFedByAdd( // x = ADD reg(killed), imm // y = XOP 0, x if (IsFwdFeederRegKilled || RegMO->isKill()) - fixupIsDeadOrKill(DefMI, MI, RegMO->getReg()); + fixupIsDeadOrKill(&DefMI, &MI, RegMO->getReg()); // Pattern 3: // ForwardKilledOperandReg = ADD reg, imm // y = XOP 0, ForwardKilledOperandReg(killed) if (ForwardKilledOperandReg != ~0U) - fixupIsDeadOrKill(DefMI, MI, ForwardKilledOperandReg); + fixupIsDeadOrKill(&DefMI, &MI, ForwardKilledOperandReg); LLVM_DEBUG(dbgs() << "With:\n"); LLVM_DEBUG(MI.dump()); @@ -4224,7 +4237,7 @@ bool PPCInstrInfo::transformToImmFormFedByLI(MachineInstr &MI, // ForwardKilledOperandReg = LI imm // y = XOP reg, ForwardKilledOperandReg(killed) if (ForwardKilledOperandReg != ~0U) - fixupIsDeadOrKill(DefMI, MI, ForwardKilledOperandReg); + fixupIsDeadOrKill(&DefMI, &MI, ForwardKilledOperandReg); return true; } diff --git a/contrib/llvm-project/llvm/lib/Target/PowerPC/PPCInstrInfo.h b/contrib/llvm-project/llvm/lib/Target/PowerPC/PPCInstrInfo.h index 43973c627fcf..556c95fef3bd 100644 --- a/contrib/llvm-project/llvm/lib/Target/PowerPC/PPCInstrInfo.h +++ b/contrib/llvm-project/llvm/lib/Target/PowerPC/PPCInstrInfo.h @@ -570,14 +570,16 @@ class PPCInstrInfo : public PPCGenInstrInfo { /// up. Before calling this function, /// 1. Ensure that \p RegNo liveness is killed after instruction \p EndMI. /// 2. Ensure that there is no new definition between (\p StartMI, \p EndMI) - /// and possible definition for \p RegNo is \p StartMI or \p EndMI. + /// and possible definition for \p RegNo is \p StartMI or \p EndMI. For + /// pre-RA cases, definition may be \p StartMI through COPY, \p StartMI + /// will be adjust to true definition. /// 3. We can do accurate fixup for the case when all instructions between /// [\p StartMI, \p EndMI] are in same basic block. /// 4. For the case when \p StartMI and \p EndMI are not in same basic block, /// we conservatively clear kill flag for all uses of \p RegNo for pre-RA /// and for post-RA, we give an assertion as without reaching definition /// analysis post-RA, \p StartMI and \p EndMI are hard to keep right. - void fixupIsDeadOrKill(MachineInstr &StartMI, MachineInstr &EndMI, + void fixupIsDeadOrKill(MachineInstr *StartMI, MachineInstr *EndMI, unsigned RegNo) const; void replaceInstrWithLI(MachineInstr &MI, const LoadImmediateInfo &LII) const; void replaceInstrOperandWithImm(MachineInstr &MI, unsigned OpNo,