+ // FIXME: This seems inappropriate to do here.
+ if (NeedFlat && MFI->IsKernel) {
+ // Insert the prologue initializing the SGPRs pointing to the scratch space
+ // for flat accesses.
+ const MachineFrameInfo *FrameInfo = MF.getFrameInfo();
+
+ // TODO: What to use with function calls?
+
+ // FIXME: This is reporting stack size that is used in a scratch buffer
+ // rather than registers as well.
+ uint64_t StackSizeBytes = FrameInfo->getStackSize();
+
+ int IndirectBegin
+ = static_cast<const AMDGPUInstrInfo*>(TII)->getIndirectIndexBegin(MF);
+ // Convert register index to 256-byte unit.
+ uint64_t StackOffset = IndirectBegin < 0 ? 0 : (4 * IndirectBegin / 256);
+
+ assert((StackSizeBytes < 0xffff) && StackOffset < 0xffff &&
+ "Stack limits should be smaller than 16-bits");
+
+ // Initialize the flat scratch register pair.
+ // TODO: Can we use one s_mov_b64 here?
+
+ // Offset is in units of 256-bytes.