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-exception 6 // 7 //==-----------------------------------------------------------------------===// 8 9 #include "R600FrameLowering.h" 10 #include "R600Subtarget.h" 11 12 using namespace llvm; 13 14 R600FrameLowering::~R600FrameLowering() = default; 15 16 /// \returns The number of registers allocated for \p FI. 17 StackOffset 18 R600FrameLowering::getFrameIndexReference(const MachineFunction &MF, int FI, 19 Register &FrameReg) const { 20 const MachineFrameInfo &MFI = MF.getFrameInfo(); 21 const R600RegisterInfo *RI 22 = MF.getSubtarget<R600Subtarget>().getRegisterInfo(); 23 24 // Fill in FrameReg output argument. 25 FrameReg = RI->getFrameRegister(MF); 26 27 // Start the offset at 2 so we don't overwrite work group information. 28 // FIXME: We should only do this when the shader actually uses this 29 // information. 30 unsigned OffsetBytes = 2 * (getStackWidth(MF) * 4); 31 int UpperBound = FI == -1 ? MFI.getNumObjects() : FI; 32 33 for (int i = MFI.getObjectIndexBegin(); i < UpperBound; ++i) { 34 OffsetBytes = alignTo(OffsetBytes, MFI.getObjectAlign(i)); 35 OffsetBytes += MFI.getObjectSize(i); 36 // Each register holds 4 bytes, so we must always align the offset to at 37 // least 4 bytes, so that 2 frame objects won't share the same register. 38 OffsetBytes = alignTo(OffsetBytes, Align(4)); 39 } 40 41 if (FI != -1) 42 OffsetBytes = alignTo(OffsetBytes, MFI.getObjectAlign(FI)); 43 44 return StackOffset::getFixed(OffsetBytes / (getStackWidth(MF) * 4)); 45 } 46