5a31a67385
This patch proposes how to deal with RISC-V vector frame objects. The layout of RISC-V vector frame will look like |---------------------------------| | scalar callee-saved registers | |---------------------------------| | scalar local variables | |---------------------------------| | scalar outgoing arguments | |---------------------------------| | RVV local variables && | | RVV outgoing arguments | |---------------------------------| <- end of frame (sp) If there is realignment or variable length array in the stack, we will use frame pointer to access fixed objects and stack pointer to access non-fixed objects. |---------------------------------| <- frame pointer (fp) | scalar callee-saved registers | |---------------------------------| | scalar local variables | |---------------------------------| | ///// realignment ///// | |---------------------------------| | scalar outgoing arguments | |---------------------------------| | RVV local variables && | | RVV outgoing arguments | |---------------------------------| <- end of frame (sp) If there are both realignment and variable length array in the stack, we will use frame pointer to access fixed objects and base pointer to access non-fixed objects. |---------------------------------| <- frame pointer (fp) | scalar callee-saved registers | |---------------------------------| | scalar local variables | |---------------------------------| | ///// realignment ///// | |---------------------------------| <- base pointer (bp) | RVV local variables && | | RVV outgoing arguments | |---------------------------------| | /////////////////////////////// | | variable length array | | /////////////////////////////// | |---------------------------------| <- end of frame (sp) | scalar outgoing arguments | |---------------------------------| In this version, we do not save the addresses of RVV objects in the stack. We access them directly through the polynomial expression (a x VLENB + b). We do not reserve frame pointer when there is any RVV object in the stack. So, we also access the scalar frame objects through the polynomial expression (a x VLENB + b) if the access across RVV stack area. Differential Revision: https://reviews.llvm.org/D94465
71 lines
2.6 KiB
C++
71 lines
2.6 KiB
C++
//=- RISCVMachineFunctionInfo.h - RISCV machine function info -----*- C++ -*-=//
|
|
//
|
|
// 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 declares RISCV-specific per-machine-function information.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef LLVM_LIB_TARGET_RISCV_RISCVMACHINEFUNCTIONINFO_H
|
|
#define LLVM_LIB_TARGET_RISCV_RISCVMACHINEFUNCTIONINFO_H
|
|
|
|
#include "RISCVSubtarget.h"
|
|
#include "llvm/CodeGen/MachineFrameInfo.h"
|
|
#include "llvm/CodeGen/MachineFunction.h"
|
|
|
|
namespace llvm {
|
|
|
|
/// RISCVMachineFunctionInfo - This class is derived from MachineFunctionInfo
|
|
/// and contains private RISCV-specific information for each MachineFunction.
|
|
class RISCVMachineFunctionInfo : public MachineFunctionInfo {
|
|
private:
|
|
/// FrameIndex for start of varargs area
|
|
int VarArgsFrameIndex = 0;
|
|
/// Size of the save area used for varargs
|
|
int VarArgsSaveSize = 0;
|
|
/// FrameIndex used for transferring values between 64-bit FPRs and a pair
|
|
/// of 32-bit GPRs via the stack.
|
|
int MoveF64FrameIndex = -1;
|
|
/// Size of any opaque stack adjustment due to save/restore libcalls.
|
|
unsigned LibCallStackSize = 0;
|
|
/// Size of RVV stack.
|
|
uint64_t RVVStackSize = 0;
|
|
|
|
public:
|
|
RISCVMachineFunctionInfo(const MachineFunction &MF) {}
|
|
|
|
int getVarArgsFrameIndex() const { return VarArgsFrameIndex; }
|
|
void setVarArgsFrameIndex(int Index) { VarArgsFrameIndex = Index; }
|
|
|
|
unsigned getVarArgsSaveSize() const { return VarArgsSaveSize; }
|
|
void setVarArgsSaveSize(int Size) { VarArgsSaveSize = Size; }
|
|
|
|
int getMoveF64FrameIndex(MachineFunction &MF) {
|
|
if (MoveF64FrameIndex == -1)
|
|
MoveF64FrameIndex =
|
|
MF.getFrameInfo().CreateStackObject(8, Align(8), false);
|
|
return MoveF64FrameIndex;
|
|
}
|
|
|
|
unsigned getLibCallStackSize() const { return LibCallStackSize; }
|
|
void setLibCallStackSize(unsigned Size) { LibCallStackSize = Size; }
|
|
|
|
bool useSaveRestoreLibCalls(const MachineFunction &MF) const {
|
|
// We cannot use fixed locations for the callee saved spill slots if the
|
|
// function uses a varargs save area.
|
|
return MF.getSubtarget<RISCVSubtarget>().enableSaveRestore() &&
|
|
VarArgsSaveSize == 0 && !MF.getFrameInfo().hasTailCall();
|
|
}
|
|
|
|
uint64_t getRVVStackSize() const { return RVVStackSize; }
|
|
void setRVVStackSize(uint64_t Size) { RVVStackSize = Size; }
|
|
};
|
|
|
|
} // end namespace llvm
|
|
|
|
#endif // LLVM_LIB_TARGET_RISCV_RISCVMACHINEFUNCTIONINFO_H
|