AMDGPU: Select scratch mubuf offsets when pointer is a constant

In call sequence setups, there may not be a frame index base
and the pointer is a constant offset from the frame
pointer / scratch wave offset register.

llvm-svn: 301230

2 files changed, 94 insertions, 34 deletions

diff --git a/llvm/lib/Target/AMDGPU/AMDGPUISelDAGToDAG.cpp b/llvm/lib/Target/AMDGPU/AMDGPUISelDAGToDAG.cpp
index 318de7f2e3d..eef59b343df 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPUISelDAGToDAG.cpp
+++ b/llvm/lib/Target/AMDGPU/AMDGPUISelDAGToDAG.cpp
@@ -116,8 +116,11 @@ private:
   bool SelectMUBUFAddr64(SDValue Addr, SDValue &SRsrc,
                          SDValue &VAddr, SDValue &SOffset, SDValue &Offset,
                          SDValue &SLC) const;
-  bool SelectMUBUFScratch(SDValue Addr, SDValue &RSrc, SDValue &VAddr,
-                          SDValue &SOffset, SDValue &ImmOffset) const;
+  bool SelectMUBUFScratchOffen(SDValue Addr, SDValue &RSrc, SDValue &VAddr,
+                               SDValue &SOffset, SDValue &ImmOffset) const;
+  bool SelectMUBUFScratchOffset(SDValue Addr, SDValue &SRsrc, SDValue &Soffset,
+                                SDValue &Offset) const;
+
   bool SelectMUBUFOffset(SDValue Addr, SDValue &SRsrc, SDValue &SOffset,
                          SDValue &Offset, SDValue &GLC, SDValue &SLC,
                          SDValue &TFE) const;
@@ -953,8 +956,12 @@ bool AMDGPUDAGToDAGISel::SelectDS64Bit4ByteAligned(SDValue Addr, SDValue &Base,
   return true;
 }
 
+static bool isLegalMUBUFImmOffset(unsigned Imm) {
+  return isUInt<12>(Imm);
+}
+
 static bool isLegalMUBUFImmOffset(const ConstantSDNode *Imm) {
-  return isUInt<12>(Imm->getZExtValue());
+  return isLegalMUBUFImmOffset(Imm->getZExtValue());
 }
 
 bool AMDGPUDAGToDAGISel::SelectMUBUF(SDValue Addr, SDValue &Ptr,
@@ -1076,9 +1083,9 @@ SDValue AMDGPUDAGToDAGISel::foldFrameIndex(SDValue N) const {
   return N;
 }
 
-bool AMDGPUDAGToDAGISel::SelectMUBUFScratch(SDValue Addr, SDValue &Rsrc,
-                                            SDValue &VAddr, SDValue &SOffset,
-                                            SDValue &ImmOffset) const {
+bool AMDGPUDAGToDAGISel::SelectMUBUFScratchOffen(SDValue Addr, SDValue &Rsrc,
+                                                 SDValue &VAddr, SDValue &SOffset,
+                                                 SDValue &ImmOffset) const {
 
   SDLoc DL(Addr);
   MachineFunction &MF = CurDAG->getMachineFunction();
@@ -1087,8 +1094,22 @@ bool AMDGPUDAGToDAGISel::SelectMUBUFScratch(SDValue Addr, SDValue &Rsrc,
   Rsrc = CurDAG->getRegister(Info->getScratchRSrcReg(), MVT::v4i32);
   SOffset = CurDAG->getRegister(Info->getScratchWaveOffsetReg(), MVT::i32);
 
-  // (add n0, c1)
+  if (ConstantSDNode *CAddr = dyn_cast<ConstantSDNode>(Addr)) {
+    unsigned Imm = CAddr->getZExtValue();
+    assert(!isLegalMUBUFImmOffset(Imm) &&
+           "should have been selected by other pattern");
+
+    SDValue HighBits = CurDAG->getTargetConstant(Imm & ~4095, DL, MVT::i32);
+    MachineSDNode *MovHighBits = CurDAG->getMachineNode(AMDGPU::V_MOV_B32_e32,
+                                                        DL, MVT::i32, HighBits);
+    VAddr = SDValue(MovHighBits, 0);
+    ImmOffset = CurDAG->getTargetConstant(Imm & 4095, DL, MVT::i16);
+    return true;
+  }
+
   if (CurDAG->isBaseWithConstantOffset(Addr)) {
+    // (add n0, c1)
+
     SDValue N0 = Addr.getOperand(0);
     SDValue N1 = Addr.getOperand(1);
 
@@ -1107,6 +1128,24 @@ bool AMDGPUDAGToDAGISel::SelectMUBUFScratch(SDValue Addr, SDValue &Rsrc,
   return true;
 }
 
+bool AMDGPUDAGToDAGISel::SelectMUBUFScratchOffset(SDValue Addr,
+                                                  SDValue &SRsrc,
+                                                  SDValue &SOffset,
+                                                  SDValue &Offset) const {
+  ConstantSDNode *CAddr = dyn_cast<ConstantSDNode>(Addr);
+  if (!CAddr || !isLegalMUBUFImmOffset(CAddr))
+    return false;
+
+  SDLoc DL(Addr);
+  MachineFunction &MF = CurDAG->getMachineFunction();
+  const SIMachineFunctionInfo *Info = MF.getInfo<SIMachineFunctionInfo>();
+
+  SRsrc = CurDAG->getRegister(Info->getScratchRSrcReg(), MVT::v4i32);
+  SOffset = CurDAG->getRegister(Info->getScratchWaveOffsetReg(), MVT::i32);
+  Offset = CurDAG->getTargetConstant(CAddr->getZExtValue(), DL, MVT::i16);
+  return true;
+}
+
 bool AMDGPUDAGToDAGISel::SelectMUBUFOffset(SDValue Addr, SDValue &SRsrc,
                                            SDValue &SOffset, SDValue &Offset,
                                            SDValue &GLC, SDValue &SLC,
diff --git a/llvm/lib/Target/AMDGPU/BUFInstructions.td b/llvm/lib/Target/AMDGPU/BUFInstructions.td
index a6609f0725a..89eddb9ce96 100644
--- a/llvm/lib/Target/AMDGPU/BUFInstructions.td
+++ b/llvm/lib/Target/AMDGPU/BUFInstructions.td
@@ -11,7 +11,9 @@ def MUBUFAddr32 : ComplexPattern<i64, 9, "SelectMUBUFAddr32">;
 def MUBUFAddr64 : ComplexPattern<i64, 7, "SelectMUBUFAddr64">;
 def MUBUFAddr64Atomic : ComplexPattern<i64, 5, "SelectMUBUFAddr64">;
 
-def MUBUFScratch : ComplexPattern<i64, 4, "SelectMUBUFScratch">;
+def MUBUFScratchOffen : ComplexPattern<i64, 4, "SelectMUBUFScratchOffen">;
+def MUBUFScratchOffset : ComplexPattern<i64, 3, "SelectMUBUFScratchOffset", [], [], 20>;
+
 def MUBUFOffset : ComplexPattern<i64, 6, "SelectMUBUFOffset">;
 def MUBUFOffsetNoGLC : ComplexPattern<i64, 3, "SelectMUBUFOffset">;
 def MUBUFOffsetAtomic : ComplexPattern<i64, 4, "SelectMUBUFOffset">;
@@ -958,21 +960,30 @@ defm : MUBUFLoad_Pattern <BUFFER_LOAD_UBYTE_OFFSET, i16, mubuf_az_extloadi8>;
 
 } // End Predicates = [Has16BitInsts]
 
-class MUBUFScratchLoadPat <MUBUF_Pseudo Instr, ValueType vt, PatFrag ld> : Pat <
-  (vt (ld (MUBUFScratch v4i32:$srsrc, i32:$vaddr,
-                        i32:$soffset, u16imm:$offset))),
-  (Instr $vaddr, $srsrc, $soffset, $offset, 0, 0, 0)
->;
+multiclass MUBUFScratchLoadPat <MUBUF_Pseudo InstrOffen,
+                                MUBUF_Pseudo InstrOffset,
+                                ValueType vt, PatFrag ld> {
+  def : Pat <
+    (vt (ld (MUBUFScratchOffen v4i32:$srsrc, i32:$vaddr,
+                               i32:$soffset, u16imm:$offset))),
+    (InstrOffen $vaddr, $srsrc, $soffset, $offset, 0, 0, 0)
+  >;
+
+  def : Pat <
+    (vt (ld (MUBUFScratchOffset v4i32:$srsrc, i32:$soffset, u16imm:$offset))),
+    (InstrOffset $srsrc, $soffset, $offset, 0, 0, 0)
+  >;
+}
 
-def : MUBUFScratchLoadPat <BUFFER_LOAD_SBYTE_OFFEN, i32, sextloadi8_private>;
-def : MUBUFScratchLoadPat <BUFFER_LOAD_UBYTE_OFFEN, i32, extloadi8_private>;
-def : MUBUFScratchLoadPat <BUFFER_LOAD_SBYTE_OFFEN, i16, sextloadi8_private>;
-def : MUBUFScratchLoadPat <BUFFER_LOAD_UBYTE_OFFEN, i16, extloadi8_private>;
-def : MUBUFScratchLoadPat <BUFFER_LOAD_SSHORT_OFFEN, i32, sextloadi16_private>;
-def : MUBUFScratchLoadPat <BUFFER_LOAD_USHORT_OFFEN, i32, extloadi16_private>;
-def : MUBUFScratchLoadPat <BUFFER_LOAD_DWORD_OFFEN, i32, load_private>;
-def : MUBUFScratchLoadPat <BUFFER_LOAD_DWORDX2_OFFEN, v2i32, load_private>;
-def : MUBUFScratchLoadPat <BUFFER_LOAD_DWORDX4_OFFEN, v4i32, load_private>;
+defm : MUBUFScratchLoadPat <BUFFER_LOAD_SBYTE_OFFEN, BUFFER_LOAD_SBYTE_OFFSET, i32, sextloadi8_private>;
+defm : MUBUFScratchLoadPat <BUFFER_LOAD_UBYTE_OFFEN, BUFFER_LOAD_UBYTE_OFFSET, i32, extloadi8_private>;
+defm : MUBUFScratchLoadPat <BUFFER_LOAD_SBYTE_OFFEN, BUFFER_LOAD_SBYTE_OFFSET, i16, sextloadi8_private>;
+defm : MUBUFScratchLoadPat <BUFFER_LOAD_UBYTE_OFFEN, BUFFER_LOAD_UBYTE_OFFSET, i16, extloadi8_private>;
+defm : MUBUFScratchLoadPat <BUFFER_LOAD_SSHORT_OFFEN, BUFFER_LOAD_SSHORT_OFFSET, i32, sextloadi16_private>;
+defm : MUBUFScratchLoadPat <BUFFER_LOAD_USHORT_OFFEN, BUFFER_LOAD_USHORT_OFFSET, i32, extloadi16_private>;
+defm : MUBUFScratchLoadPat <BUFFER_LOAD_DWORD_OFFEN, BUFFER_LOAD_DWORD_OFFSET, i32, load_private>;
+defm : MUBUFScratchLoadPat <BUFFER_LOAD_DWORDX2_OFFEN, BUFFER_LOAD_DWORDX2_OFFSET, v2i32, load_private>;
+defm : MUBUFScratchLoadPat <BUFFER_LOAD_DWORDX4_OFFEN, BUFFER_LOAD_DWORDX4_OFFSET, v4i32, load_private>;
 
 // BUFFER_LOAD_DWORD*, addr64=0
 multiclass MUBUF_Load_Dword <ValueType vt,
@@ -1054,19 +1065,29 @@ multiclass MUBUFStore_Pattern <MUBUF_Pseudo Instr_OFFSET, ValueType vt,
 defm : MUBUFStore_Pattern <BUFFER_STORE_BYTE_OFFSET, i16, truncstorei8_global>;
 defm : MUBUFStore_Pattern <BUFFER_STORE_SHORT_OFFSET, i16, global_store>;
 
-class MUBUFScratchStorePat <MUBUF_Pseudo Instr, ValueType vt, PatFrag st> : Pat <
-  (st vt:$value, (MUBUFScratch v4i32:$srsrc, i32:$vaddr, i32:$soffset,
-                               u16imm:$offset)),
-  (Instr $value, $vaddr, $srsrc, $soffset, $offset, 0, 0, 0)
->;
+multiclass MUBUFScratchStorePat <MUBUF_Pseudo InstrOffen,
+                                 MUBUF_Pseudo InstrOffset,
+                                 ValueType vt, PatFrag st> {
+  def : Pat <
+    (st vt:$value, (MUBUFScratchOffen v4i32:$srsrc, i32:$vaddr,
+                                      i32:$soffset, u16imm:$offset)),
+    (InstrOffen $value, $vaddr, $srsrc, $soffset, $offset, 0, 0, 0)
+  >;
+
+  def : Pat <
+    (st vt:$value, (MUBUFScratchOffset v4i32:$srsrc, i32:$soffset,
+                                       u16imm:$offset)),
+    (InstrOffset $value, $srsrc, $soffset, $offset, 0, 0, 0)
+  >;
+}
 
-def : MUBUFScratchStorePat <BUFFER_STORE_BYTE_OFFEN, i32, truncstorei8_private>;
-def : MUBUFScratchStorePat <BUFFER_STORE_SHORT_OFFEN, i32, truncstorei16_private>;
-def : MUBUFScratchStorePat <BUFFER_STORE_BYTE_OFFEN, i16, truncstorei8_private>;
-def : MUBUFScratchStorePat <BUFFER_STORE_SHORT_OFFEN, i16, store_private>;
-def : MUBUFScratchStorePat <BUFFER_STORE_DWORD_OFFEN, i32, store_private>;
-def : MUBUFScratchStorePat <BUFFER_STORE_DWORDX2_OFFEN, v2i32, store_private>;
-def : MUBUFScratchStorePat <BUFFER_STORE_DWORDX4_OFFEN, v4i32, store_private>;
+defm : MUBUFScratchStorePat <BUFFER_STORE_BYTE_OFFEN, BUFFER_STORE_BYTE_OFFSET, i32, truncstorei8_private>;
+defm : MUBUFScratchStorePat <BUFFER_STORE_SHORT_OFFEN, BUFFER_STORE_SHORT_OFFSET, i32, truncstorei16_private>;
+defm : MUBUFScratchStorePat <BUFFER_STORE_BYTE_OFFEN, BUFFER_STORE_BYTE_OFFSET, i16, truncstorei8_private>;
+defm : MUBUFScratchStorePat <BUFFER_STORE_SHORT_OFFEN, BUFFER_STORE_SHORT_OFFSET, i16, store_private>;
+defm : MUBUFScratchStorePat <BUFFER_STORE_DWORD_OFFEN, BUFFER_STORE_DWORD_OFFSET, i32, store_private>;
+defm : MUBUFScratchStorePat <BUFFER_STORE_DWORDX2_OFFEN, BUFFER_STORE_DWORDX2_OFFSET, v2i32, store_private>;
+defm : MUBUFScratchStorePat <BUFFER_STORE_DWORDX4_OFFEN, BUFFER_STORE_DWORDX4_OFFSET, v4i32, store_private>;
 
 //===----------------------------------------------------------------------===//
 // MTBUF Patterns