R600/SI: Use external symbols for scratch buffer

We were passing the scratch buffer address to the shaders via user sgprs,
but now we use external symbols and have the driver patch the shader
using reloc information.

llvm-svn: 226586

1 files changed, 16 insertions, 5 deletions

diff --git a/llvm/lib/Target/R600/AMDGPUISelDAGToDAG.cpp b/llvm/lib/Target/R600/AMDGPUISelDAGToDAG.cpp
index 28b4183d277..e0e81680cc0 100644
--- a/llvm/lib/Target/R600/AMDGPUISelDAGToDAG.cpp
+++ b/llvm/lib/Target/R600/AMDGPUISelDAGToDAG.cpp
@@ -962,16 +962,27 @@ bool AMDGPUDAGToDAGISel::SelectMUBUFScratch(SDValue Addr, SDValue &Rsrc,
   const SITargetLowering& Lowering =
     *static_cast<const SITargetLowering*>(getTargetLowering());
 
-  unsigned ScratchPtrReg =
-      TRI->getPreloadedValue(MF, SIRegisterInfo::SCRATCH_PTR);
   unsigned ScratchOffsetReg =
       TRI->getPreloadedValue(MF, SIRegisterInfo::SCRATCH_WAVE_OFFSET);
   Lowering.CreateLiveInRegister(*CurDAG, &AMDGPU::SReg_32RegClass,
                                 ScratchOffsetReg, MVT::i32);
+  SDValue Sym0 = CurDAG->getExternalSymbol("SCRATCH_RSRC_DWORD0", MVT::i32);
+  SDValue ScratchRsrcDword0 =
+      SDValue(CurDAG->getMachineNode(AMDGPU::S_MOV_B32, DL, MVT::i32, Sym0), 0);
 
-  SDValue ScratchPtr =
-    CurDAG->getCopyFromReg(CurDAG->getEntryNode(), DL,
-                           MRI.getLiveInVirtReg(ScratchPtrReg), MVT::i64);
+  SDValue Sym1 = CurDAG->getExternalSymbol("SCRATCH_RSRC_DWORD1", MVT::i32);
+  SDValue ScratchRsrcDword1 =
+      SDValue(CurDAG->getMachineNode(AMDGPU::S_MOV_B32, DL, MVT::i32, Sym1), 0);
+
+  const SDValue RsrcOps[] = {
+      CurDAG->getTargetConstant(AMDGPU::SReg_64RegClassID, MVT::i32),
+      ScratchRsrcDword0,
+      CurDAG->getTargetConstant(AMDGPU::sub0, MVT::i32),
+      ScratchRsrcDword1,
+      CurDAG->getTargetConstant(AMDGPU::sub1, MVT::i32),
+  };
+  SDValue ScratchPtr = SDValue(CurDAG->getMachineNode(AMDGPU::REG_SEQUENCE, DL,
+                                              MVT::v2i32, RsrcOps), 0);
   Rsrc = SDValue(Lowering.buildScratchRSRC(*CurDAG, DL, ScratchPtr), 0);
   SOffset = CurDAG->getCopyFromReg(CurDAG->getEntryNode(), DL,
       MRI.getLiveInVirtReg(ScratchOffsetReg), MVT::i32);