Index: lib/Target/AMDGPU/SIISelLowering.cpp
===================================================================
--- lib/Target/AMDGPU/SIISelLowering.cpp
+++ lib/Target/AMDGPU/SIISelLowering.cpp
@@ -1030,6 +1030,10 @@
   EVT MemVT;
   SDValue Param;
   if (Subtarget->isAmdHsaOS()) {
+    const SIMachineFunctionInfo *MFI = MF.getInfo<SIMachineFunctionInfo>();
+    (void) MFI;
+    assert(MFI->hasDispatchPtr());
+
     BasePtr = TRI->getPreloadedValue(MF, SIRegisterInfo::DISPATCH_PTR);
 
     // Local size value are 16-bits, but we always load 32-bit values and
Index: lib/Target/AMDGPU/SIMachineFunctionInfo.h
===================================================================
--- lib/Target/AMDGPU/SIMachineFunctionInfo.h
+++ lib/Target/AMDGPU/SIMachineFunctionInfo.h
@@ -31,11 +31,38 @@
   unsigned TIDReg;
   unsigned ScratchRSrcReg;
 
+public:
+  // FIXME: Make private
+  unsigned LDSWaveSpillSize;
+  unsigned PSInputAddr;
+  std::map<unsigned, unsigned> LaneVGPRs;
+  unsigned ScratchOffsetReg;
+  unsigned NumUserSGPRs;
+
+private:
   bool HasSpilledSGPRs;
   bool HasSpilledVGPRs;
 
-public:
+  // Feature bits required for inputs passed in user / system SGPRs.
+  bool DispatchPtr : 1;
+  bool QueuePtr : 1;
+  bool DispatchID : 1;
+  bool KernargSegmentPtr : 1;
+  bool FlatScratchInit : 1;
+  bool GridWorkgroupCountX : 1;
+  bool GridWorkgroupCountY : 1;
+  bool GridWorkgroupCountZ : 1;
+
+  bool WorkGroupIDX : 1; // Always initialized.
+  bool WorkGroupIDY : 1;
+  bool WorkGroupIDZ : 1;
+  bool WorkGroupInfo : 1;
+
+  bool WorkItemIDX : 1; // Always initialized.
+  bool WorkItemIDY : 1;
+  bool WorkItemIDZ : 1;
 
+public:
   struct SpilledReg {
     unsigned VGPR;
     int Lane;
@@ -49,15 +76,71 @@
   SIMachineFunctionInfo(const MachineFunction &MF);
   SpilledReg getSpilledReg(MachineFunction *MF, unsigned FrameIndex,
                            unsigned SubIdx);
-  unsigned PSInputAddr;
-  unsigned NumUserSGPRs;
-  std::map<unsigned, unsigned> LaneVGPRs;
-  unsigned LDSWaveSpillSize;
-  unsigned ScratchOffsetReg;
   bool hasCalculatedTID() const { return TIDReg != AMDGPU::NoRegister; };
   unsigned getTIDReg() const { return TIDReg; };
   void setTIDReg(unsigned Reg) { TIDReg = Reg; }
 
+
+  bool hasDispatchPtr() const {
+    return DispatchPtr;
+  }
+
+  bool hasQueuePtr() const {
+    return QueuePtr;
+  }
+
+  bool hasDispatchID() const {
+    return DispatchID;
+  }
+
+  bool hasKernargSegmentPtr() const {
+    return KernargSegmentPtr;
+  }
+
+  bool hasFlatScratchInit() const {
+    return FlatScratchInit;
+  }
+
+  bool hasGridWorkgroupCountX() const {
+    return GridWorkgroupCountX;
+  }
+
+  bool hasGridWorkgroupCountY() const {
+    return GridWorkgroupCountY;
+  }
+
+  bool hasGridWorkgroupCountZ() const {
+    return GridWorkgroupCountZ;
+  }
+
+  bool hasWorkGroupIDX() const {
+    return WorkGroupIDX;
+  }
+
+  bool hasWorkGroupIDY() const {
+    return WorkGroupIDY;
+  }
+
+  bool hasWorkGroupIDZ() const {
+    return WorkGroupIDZ;
+  }
+
+  bool hasWorkGroupInfo() const {
+    return WorkGroupInfo;
+  }
+
+  bool hasWorkItemIDX() const {
+    return WorkItemIDX;
+  }
+
+  bool hasWorkItemIDY() const {
+    return WorkItemIDY;
+  }
+
+  bool hasWorkItemIDZ() const {
+    return WorkItemIDZ;
+  }
+
   /// \brief Returns the physical register reserved for use as the resource
   /// descriptor for scratch accesses.
   unsigned getScratchRSrcReg() const {
Index: lib/Target/AMDGPU/SIMachineFunctionInfo.cpp
===================================================================
--- lib/Target/AMDGPU/SIMachineFunctionInfo.cpp
+++ lib/Target/AMDGPU/SIMachineFunctionInfo.cpp
@@ -30,11 +30,43 @@
   : AMDGPUMachineFunction(MF),
     TIDReg(AMDGPU::NoRegister),
     ScratchRSrcReg(AMDGPU::NoRegister),
-    HasSpilledSGPRs(false),
-    HasSpilledVGPRs(false),
+    LDSWaveSpillSize(0),
     PSInputAddr(0),
     NumUserSGPRs(0),
-    LDSWaveSpillSize(0) { }
+    HasSpilledSGPRs(false),
+    HasSpilledVGPRs(false),
+    DispatchPtr(false),
+    QueuePtr(false),
+    DispatchID(false),
+    KernargSegmentPtr(true),
+    FlatScratchInit(false),
+    GridWorkgroupCountX(false),
+    GridWorkgroupCountY(false),
+    GridWorkgroupCountZ(false),
+    WorkGroupIDX(true),
+    WorkGroupIDY(false),
+    WorkGroupIDZ(false),
+    WorkGroupInfo(false),
+    WorkItemIDX(true),
+    WorkItemIDY(false),
+    WorkItemIDZ(false) {
+  const Function *F = MF.getFunction();
+
+  if (F->hasFnAttribute("amdgpu-dispatch-ptr"))
+    DispatchPtr = true;
+
+  if (F->hasFnAttribute("amdgpu-work-group-id-y"))
+    WorkGroupIDY = true;
+
+  if (F->hasFnAttribute("amdgpu-work-group-id-z"))
+    WorkGroupIDZ = true;
+
+  if (F->hasFnAttribute("amdgpu-work-item-id-y"))
+    WorkItemIDY = true;
+
+  if (F->hasFnAttribute("amdgpu-work-item-id-z"))
+    WorkItemIDZ = true;
+}
 
 void SIMachineFunctionInfo::setScratchRSrcReg(const SIRegisterInfo *TRI) {
   // We need to round up to next multiple of 4.