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-rw-r--r--contrib/llvm/lib/Target/R600/SIMachineFunctionInfo.cpp97
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diff --git a/contrib/llvm/lib/Target/R600/SIMachineFunctionInfo.cpp b/contrib/llvm/lib/Target/R600/SIMachineFunctionInfo.cpp
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+//===-- SIMachineFunctionInfo.cpp - SI Machine Function Info -------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+/// \file
+//===----------------------------------------------------------------------===//
+
+
+#include "SIMachineFunctionInfo.h"
+#include "SIInstrInfo.h"
+#include "SIRegisterInfo.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/LLVMContext.h"
+
+#define MAX_LANES 64
+
+using namespace llvm;
+
+
+// Pin the vtable to this file.
+void SIMachineFunctionInfo::anchor() {}
+
+SIMachineFunctionInfo::SIMachineFunctionInfo(const MachineFunction &MF)
+ : AMDGPUMachineFunction(MF),
+ PSInputAddr(0),
+ SpillTracker(),
+ NumUserSGPRs(0) { }
+
+static unsigned createLaneVGPR(MachineRegisterInfo &MRI, MachineFunction *MF) {
+ unsigned VGPR = MRI.createVirtualRegister(&AMDGPU::VReg_32RegClass);
+
+ // We need to add this register as live out for the function, in order to
+ // have the live range calculated directly.
+ //
+ // When register spilling begins, we have already calculated the live
+ // live intervals for all the registers. Since we are spilling SGPRs to
+ // VGPRs, we need to update the Lane VGPR's live interval every time we
+ // spill or restore a register.
+ //
+ // Unfortunately, there is no good way to update the live interval as
+ // the TargetInstrInfo callbacks for spilling and restoring don't give
+ // us access to the live interval information.
+ //
+ // We are lucky, though, because the InlineSpiller calls
+ // LiveRangeEdit::calculateRegClassAndHint() which iterates through
+ // all the new register that have been created when restoring a register
+ // and calls LiveIntervals::getInterval(), which creates and computes
+ // the live interval for the newly created register. However, once this
+ // live intervals is created, it doesn't change and since we usually reuse
+ // the Lane VGPR multiple times, this means any uses after the first aren't
+ // added to the live interval.
+ //
+ // To work around this, we add Lane VGPRs to the functions live out list,
+ // so that we can guarantee its live range will cover all of its uses.
+
+ for (MachineBasicBlock &MBB : *MF) {
+ if (MBB.back().getOpcode() == AMDGPU::S_ENDPGM) {
+ MBB.back().addOperand(*MF, MachineOperand::CreateReg(VGPR, false, true));
+ return VGPR;
+ }
+ }
+
+ LLVMContext &Ctx = MF->getFunction()->getContext();
+ Ctx.emitError("Could not find S_ENDPGM instruction.");
+
+ return VGPR;
+}
+
+unsigned SIMachineFunctionInfo::RegSpillTracker::reserveLanes(
+ MachineRegisterInfo &MRI, MachineFunction *MF, unsigned NumRegs) {
+ unsigned StartLane = CurrentLane;
+ CurrentLane += NumRegs;
+ if (!LaneVGPR) {
+ LaneVGPR = createLaneVGPR(MRI, MF);
+ } else {
+ if (CurrentLane >= MAX_LANES) {
+ StartLane = CurrentLane = 0;
+ LaneVGPR = createLaneVGPR(MRI, MF);
+ }
+ }
+ return StartLane;
+}
+
+void SIMachineFunctionInfo::RegSpillTracker::addSpilledReg(unsigned FrameIndex,
+ unsigned Reg,
+ int Lane) {
+ SpilledRegisters[FrameIndex] = SpilledReg(Reg, Lane);
+}
+
+const SIMachineFunctionInfo::SpilledReg&
+SIMachineFunctionInfo::RegSpillTracker::getSpilledReg(unsigned FrameIndex) {
+ return SpilledRegisters[FrameIndex];
+}
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