llvm/llvm/lib/CodeGen/CodeGenCommonISel.cpp

//===-- CodeGenCommonISel.cpp ---------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file defines common utilies that are shared between SelectionDAG and
// GlobalISel frameworks.
//
//===----------------------------------------------------------------------===//

#include "llvm/CodeGen/CodeGenCommonISel.h"
#include "llvm/Analysis/BranchProbabilityInfo.h"
#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/TargetInstrInfo.h"
#include "llvm/CodeGen/TargetOpcodes.h"
#include "llvm/IR/DebugInfoMetadata.h"

#define DEBUG_TYPE …

usingnamespacellvm;

/// Add a successor MBB to ParentMBB< creating a new MachineBB for BB if SuccMBB
/// is 0.
MachineBasicBlock *
StackProtectorDescriptor::addSuccessorMBB(
    const BasicBlock *BB, MachineBasicBlock *ParentMBB, bool IsLikely,
    MachineBasicBlock *SuccMBB) { … }

/// Given that the input MI is before a partial terminator sequence TSeq, return
/// true if M + TSeq also a partial terminator sequence.
///
/// A Terminator sequence is a sequence of MachineInstrs which at this point in
/// lowering copy vregs into physical registers, which are then passed into
/// terminator instructors so we can satisfy ABI constraints. A partial
/// terminator sequence is an improper subset of a terminator sequence (i.e. it
/// may be the whole terminator sequence).
static bool MIIsInTerminatorSequence(const MachineInstr &MI) { … }

/// Find the split point at which to splice the end of BB into its success stack
/// protector check machine basic block.
///
/// On many platforms, due to ABI constraints, terminators, even before register
/// allocation, use physical registers. This creates an issue for us since
/// physical registers at this point can not travel across basic
/// blocks. Luckily, selectiondag always moves physical registers into vregs
/// when they enter functions and moves them through a sequence of copies back
/// into the physical registers right before the terminator creating a
/// ``Terminator Sequence''. This function is searching for the beginning of the
/// terminator sequence so that we can ensure that we splice off not just the
/// terminator, but additionally the copies that move the vregs into the
/// physical registers.
MachineBasicBlock::iterator
llvm::findSplitPointForStackProtector(MachineBasicBlock *BB,
                                      const TargetInstrInfo &TII) { … }

FPClassTest llvm::invertFPClassTestIfSimpler(FPClassTest Test, bool UseFCmp) { … }

static MachineOperand *getSalvageOpsForCopy(const MachineRegisterInfo &MRI,
                                            MachineInstr &Copy) { … }

static MachineOperand *getSalvageOpsForTrunc(const MachineRegisterInfo &MRI,
                                            MachineInstr &Trunc,
                                            SmallVectorImpl<uint64_t> &Ops) { … }

static MachineOperand *salvageDebugInfoImpl(const MachineRegisterInfo &MRI,
                                            MachineInstr &MI,
                                            SmallVectorImpl<uint64_t> &Ops) { … }

void llvm::salvageDebugInfoForDbgValue(const MachineRegisterInfo &MRI,
                                       MachineInstr &MI,
                                       ArrayRef<MachineOperand *> DbgUsers) { … }