llvm/llvm/lib/CodeGen/CallingConvLower.cpp

//===-- CallingConvLower.cpp - Calling Conventions ------------------------===//
//
// 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 implements the CCState class, used for lowering and implementing
// calling conventions.
//
//===----------------------------------------------------------------------===//

#include "llvm/CodeGen/CallingConvLower.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/TargetLowering.h"
#include "llvm/CodeGen/TargetRegisterInfo.h"
#include "llvm/CodeGen/TargetSubtargetInfo.h"
#include "llvm/MC/MCRegisterInfo.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/SaveAndRestore.h"
#include "llvm/Support/raw_ostream.h"

usingnamespacellvm;

CCState::CCState(CallingConv::ID CC, bool IsVarArg, MachineFunction &MF,
                 SmallVectorImpl<CCValAssign> &Locs, LLVMContext &Context,
                 bool NegativeOffsets)
    : … { … }

/// Allocate space on the stack large enough to pass an argument by value.
/// The size and alignment information of the argument is encoded in
/// its parameter attribute.
void CCState::HandleByVal(unsigned ValNo, MVT ValVT, MVT LocVT,
                          CCValAssign::LocInfo LocInfo, int MinSize,
                          Align MinAlign, ISD::ArgFlagsTy ArgFlags) { … }

/// Mark a register and all of its aliases as allocated.
void CCState::MarkAllocated(MCPhysReg Reg) { … }

void CCState::MarkUnallocated(MCPhysReg Reg) { … }

bool CCState::IsShadowAllocatedReg(MCRegister Reg) const { … }

/// Analyze an array of argument values,
/// incorporating info about the formals into this state.
void
CCState::AnalyzeFormalArguments(const SmallVectorImpl<ISD::InputArg> &Ins,
                                CCAssignFn Fn) { … }

/// Analyze the return values of a function, returning true if the return can
/// be performed without sret-demotion and false otherwise.
bool CCState::CheckReturn(const SmallVectorImpl<ISD::OutputArg> &Outs,
                          CCAssignFn Fn) { … }

/// Analyze the returned values of a return,
/// incorporating info about the result values into this state.
void CCState::AnalyzeReturn(const SmallVectorImpl<ISD::OutputArg> &Outs,
                            CCAssignFn Fn) { … }

/// Analyze the outgoing arguments to a call,
/// incorporating info about the passed values into this state.
void CCState::AnalyzeCallOperands(const SmallVectorImpl<ISD::OutputArg> &Outs,
                                  CCAssignFn Fn) { … }

/// Same as above except it takes vectors of types and argument flags.
void CCState::AnalyzeCallOperands(SmallVectorImpl<MVT> &ArgVTs,
                                  SmallVectorImpl<ISD::ArgFlagsTy> &Flags,
                                  CCAssignFn Fn) { … }

/// Analyze the return values of a call, incorporating info about the passed
/// values into this state.
void CCState::AnalyzeCallResult(const SmallVectorImpl<ISD::InputArg> &Ins,
                                CCAssignFn Fn) { … }

/// Same as above except it's specialized for calls that produce a single value.
void CCState::AnalyzeCallResult(MVT VT, CCAssignFn Fn) { … }

void CCState::ensureMaxAlignment(Align Alignment) { … }

static bool isValueTypeInRegForCC(CallingConv::ID CC, MVT VT) { … }

void CCState::getRemainingRegParmsForType(SmallVectorImpl<MCPhysReg> &Regs,
                                          MVT VT, CCAssignFn Fn) { … }

void CCState::analyzeMustTailForwardedRegisters(
    SmallVectorImpl<ForwardedRegister> &Forwards, ArrayRef<MVT> RegParmTypes,
    CCAssignFn Fn) { … }

bool CCState::resultsCompatible(CallingConv::ID CalleeCC,
                                CallingConv::ID CallerCC, MachineFunction &MF,
                                LLVMContext &C,
                                const SmallVectorImpl<ISD::InputArg> &Ins,
                                CCAssignFn CalleeFn, CCAssignFn CallerFn) { … }