47 lines · cpp
1//===----------------------- R600FrameLowering.cpp ------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//==-----------------------------------------------------------------------===//8 9#include "R600FrameLowering.h"10#include "R600Subtarget.h"11#include "llvm/CodeGen/MachineFrameInfo.h"12 13using namespace llvm;14 15R600FrameLowering::~R600FrameLowering() = default;16 17/// \returns The number of registers allocated for \p FI.18StackOffset19R600FrameLowering::getFrameIndexReference(const MachineFunction &MF, int FI,20 Register &FrameReg) const {21 const MachineFrameInfo &MFI = MF.getFrameInfo();22 const R600RegisterInfo *RI23 = MF.getSubtarget<R600Subtarget>().getRegisterInfo();24 25 // Fill in FrameReg output argument.26 FrameReg = RI->getFrameRegister(MF);27 28 // Start the offset at 2 so we don't overwrite work group information.29 // FIXME: We should only do this when the shader actually uses this30 // information.31 unsigned OffsetBytes = 2 * (getStackWidth(MF) * 4);32 int UpperBound = FI == -1 ? MFI.getNumObjects() : FI;33 34 for (int i = MFI.getObjectIndexBegin(); i < UpperBound; ++i) {35 OffsetBytes = alignTo(OffsetBytes, MFI.getObjectAlign(i));36 OffsetBytes += MFI.getObjectSize(i);37 // Each register holds 4 bytes, so we must always align the offset to at38 // least 4 bytes, so that 2 frame objects won't share the same register.39 OffsetBytes = alignTo(OffsetBytes, Align(4));40 }41 42 if (FI != -1)43 OffsetBytes = alignTo(OffsetBytes, MFI.getObjectAlign(FI));44 45 return StackOffset::getFixed(OffsetBytes / (getStackWidth(MF) * 4));46}47