AMDGPU: Refactor copyPhysReg

[arsenm]

Summary

Separate the subregister splitting logic to re-use later.

[• tstellarAMD]

This looks like the wrong patch.

[arsenm]

Attach right patch

[• tstellarAMD]

lib/Target/AMDGPU/SIInstrInfo.cpp

409

We are supposed to use AMDGPU::getRegBitWidth() now.

[arsenm]

Use getRegBitWidth

[• tstellarAMD]

LGTM.

[arsenm]

r286118

lib/Target/AMDGPU/SIInstrInfo.cpp

bool SIInstrInfo::shouldClusterMemOps(MachineInstr &FirstLdSt,
 
   return (NumLoads * DstRC->getSize()) <= LoadClusterThreshold;
 }
 
 void SIInstrInfo::copyPhysReg(MachineBasicBlock &MBB,
                               MachineBasicBlock::iterator MI,
                               const DebugLoc &DL, unsigned DestReg,
                               unsigned SrcReg, bool KillSrc) const {
+  const TargetRegisterClass *RC = RI.getPhysRegClass(DestReg);
 
-  static const int16_t Sub0_15[] = {
-    AMDGPU::sub0, AMDGPU::sub1, AMDGPU::sub2, AMDGPU::sub3,
-    AMDGPU::sub4, AMDGPU::sub5, AMDGPU::sub6, AMDGPU::sub7,
-    AMDGPU::sub8, AMDGPU::sub9, AMDGPU::sub10, AMDGPU::sub11,
-    AMDGPU::sub12, AMDGPU::sub13, AMDGPU::sub14, AMDGPU::sub15,
-  };
-
-  static const int16_t Sub0_15_64[] = {
-    AMDGPU::sub0_sub1, AMDGPU::sub2_sub3,
-    AMDGPU::sub4_sub5, AMDGPU::sub6_sub7,
-    AMDGPU::sub8_sub9, AMDGPU::sub10_sub11,
-    AMDGPU::sub12_sub13, AMDGPU::sub14_sub15,
-  };
-
-  static const int16_t Sub0_7[] = {
-    AMDGPU::sub0, AMDGPU::sub1, AMDGPU::sub2, AMDGPU::sub3,
-    AMDGPU::sub4, AMDGPU::sub5, AMDGPU::sub6, AMDGPU::sub7,
-  };
-
-  static const int16_t Sub0_7_64[] = {
-    AMDGPU::sub0_sub1, AMDGPU::sub2_sub3,
-    AMDGPU::sub4_sub5, AMDGPU::sub6_sub7,
-  };
-
-  static const int16_t Sub0_3[] = {
-    AMDGPU::sub0, AMDGPU::sub1, AMDGPU::sub2, AMDGPU::sub3,
-  };
-
-  static const int16_t Sub0_3_64[] = {
-    AMDGPU::sub0_sub1, AMDGPU::sub2_sub3,
-  };
-
-  static const int16_t Sub0_2[] = {
-    AMDGPU::sub0, AMDGPU::sub1, AMDGPU::sub2,
-  };
-
-  static const int16_t Sub0_1[] = {
-    AMDGPU::sub0, AMDGPU::sub1,
-  };
-
-  unsigned Opcode;
-  ArrayRef<int16_t> SubIndices;
+  if (RC == &AMDGPU::VGPR_32RegClass) {
+    assert(AMDGPU::VGPR_32RegClass.contains(SrcReg) ||
+           AMDGPU::SReg_32RegClass.contains(SrcReg));
+    BuildMI(MBB, MI, DL, get(AMDGPU::V_MOV_B32_e32), DestReg)
+      .addReg(SrcReg, getKillRegState(KillSrc));
+    return;
+  }
 
-  if (AMDGPU::SReg_32RegClass.contains(DestReg)) {
+  if (RC == &AMDGPU::SReg_32RegClass) {
     if (SrcReg == AMDGPU::SCC) {
       BuildMI(MBB, MI, DL, get(AMDGPU::S_CSELECT_B32), DestReg)
           .addImm(-1)
           .addImm(0);
       return;
     }
 
     assert(AMDGPU::SReg_32RegClass.contains(SrcReg));
     BuildMI(MBB, MI, DL, get(AMDGPU::S_MOV_B32), DestReg)
             .addReg(SrcReg, getKillRegState(KillSrc));
     return;
+  }
 
-  } else if (AMDGPU::SReg_64RegClass.contains(DestReg)) {
+  if (RC == &AMDGPU::SReg_64RegClass) {
     if (DestReg == AMDGPU::VCC) {
       if (AMDGPU::SReg_64RegClass.contains(SrcReg)) {
         BuildMI(MBB, MI, DL, get(AMDGPU::S_MOV_B64), AMDGPU::VCC)
           .addReg(SrcReg, getKillRegState(KillSrc));
       } else {
         // FIXME: Hack until VReg_1 removed.
         assert(AMDGPU::VGPR_32RegClass.contains(SrcReg));
         BuildMI(MBB, MI, DL, get(AMDGPU::V_CMP_NE_U32_e32))
           .addImm(0)
           .addReg(SrcReg, getKillRegState(KillSrc));
       }
 
       return;
     }
 
     assert(AMDGPU::SReg_64RegClass.contains(SrcReg));
     BuildMI(MBB, MI, DL, get(AMDGPU::S_MOV_B64), DestReg)
             .addReg(SrcReg, getKillRegState(KillSrc));
     return;
+  }
 
-  } else if (DestReg == AMDGPU::SCC) {
+  if (DestReg == AMDGPU::SCC) {
     assert(AMDGPU::SReg_32RegClass.contains(SrcReg));
     BuildMI(MBB, MI, DL, get(AMDGPU::S_CMP_LG_U32))
-        .addReg(SrcReg, getKillRegState(KillSrc))
-        .addImm(0);
     return;
-  } else if (AMDGPU::SReg_128RegClass.contains(DestReg)) {
-    assert(AMDGPU::SReg_128RegClass.contains(SrcReg));
-    Opcode = AMDGPU::S_MOV_B64;
-    SubIndices = Sub0_3_64;
-
-  } else if (AMDGPU::SReg_256RegClass.contains(DestReg)) {
-    assert(AMDGPU::SReg_256RegClass.contains(SrcReg));
-    Opcode = AMDGPU::S_MOV_B64;
-    SubIndices = Sub0_7_64;
+  }
 
-  } else if (AMDGPU::SReg_512RegClass.contains(DestReg)) {
-    assert(AMDGPU::SReg_512RegClass.contains(SrcReg));
-    Opcode = AMDGPU::S_MOV_B64;
-    SubIndices = Sub0_15_64;
-
-  } else if (AMDGPU::VGPR_32RegClass.contains(DestReg)) {
-    assert(AMDGPU::VGPR_32RegClass.contains(SrcReg) ||
-           AMDGPU::SReg_32RegClass.contains(SrcReg));
-    BuildMI(MBB, MI, DL, get(AMDGPU::V_MOV_B32_e32), DestReg)
-            .addReg(SrcReg, getKillRegState(KillSrc));
-    return;
-
-  } else if (AMDGPU::VReg_64RegClass.contains(DestReg)) {
-    assert(AMDGPU::VReg_64RegClass.contains(SrcReg) ||
-           AMDGPU::SReg_64RegClass.contains(SrcReg));
-    Opcode = AMDGPU::V_MOV_B32_e32;
-    SubIndices = Sub0_1;
-
-  } else if (AMDGPU::VReg_96RegClass.contains(DestReg)) {
-    assert(AMDGPU::VReg_96RegClass.contains(SrcReg));
-    Opcode = AMDGPU::V_MOV_B32_e32;
-    SubIndices = Sub0_2;
-
-  } else if (AMDGPU::VReg_128RegClass.contains(DestReg)) {
-    assert(AMDGPU::VReg_128RegClass.contains(SrcReg) ||
-           AMDGPU::SReg_128RegClass.contains(SrcReg));
-    Opcode = AMDGPU::V_MOV_B32_e32;
-    SubIndices = Sub0_3;
-
-  } else if (AMDGPU::VReg_256RegClass.contains(DestReg)) {
-    assert(AMDGPU::VReg_256RegClass.contains(SrcReg) ||
-           AMDGPU::SReg_256RegClass.contains(SrcReg));
-    Opcode = AMDGPU::V_MOV_B32_e32;
-    SubIndices = Sub0_7;
-
-  } else if (AMDGPU::VReg_512RegClass.contains(DestReg)) {
-    assert(AMDGPU::VReg_512RegClass.contains(SrcReg) ||
-           AMDGPU::SReg_512RegClass.contains(SrcReg));
-    Opcode = AMDGPU::V_MOV_B32_e32;
-    SubIndices = Sub0_15;
-
+  unsigned EltSize = 4;
+  unsigned Opcode = AMDGPU::V_MOV_B32_e32;
+  if (RI.isSGPRClass(RC)) {
+    if (RC->getSize() > 4) {
+      Opcode =  AMDGPU::S_MOV_B64;
+      EltSize = 8;
     } else {
-    llvm_unreachable("Can't copy register!");
+      Opcode = AMDGPU::S_MOV_B32;
+      EltSize = 4;
+    }
   }
 
+  ArrayRef<int16_t> SubIndices = RI.getRegSplitParts(RC, EltSize);
   bool Forward = RI.getHWRegIndex(DestReg) <= RI.getHWRegIndex(SrcReg);
 
   for (unsigned Idx = 0; Idx < SubIndices.size(); ++Idx) {
     unsigned SubIdx;
     if (Forward)
       SubIdx = SubIndices[Idx];
     else
       SubIdx = SubIndices[SubIndices.size() - Idx - 1];

lib/Target/AMDGPU/SIRegisterInfo.h

public:
   /// requested using "amdgpu-num-vgpr" attribute attached to function \p MF.
   ///
   /// \returns Value that meets number of waves per execution unit requirement
   /// if explicitly requested value cannot be converted to integer, violates
   /// subtarget's specifications, or does not meet number of waves per execution
   /// unit requirement.
   unsigned getMaxNumVGPRs(const MachineFunction &MF) const;
 
+  ArrayRef<int16_t> getRegSplitParts(const TargetRegisterClass *RC,
+                                     unsigned EltSize) const;
+
 private:
   void buildScratchLoadStore(MachineBasicBlock::iterator MI,
                              unsigned LoadStoreOp, const MachineOperand *SrcDst,
                              unsigned ScratchRsrcReg, unsigned ScratchOffset,
                              int64_t Offset,
                              RegScavenger *RS) const;
 };
 
 } // End namespace llvm
 
 #endif

lib/Target/AMDGPU/SIRegisterInfo.cpp

if (WavesPerEU.second &&
       Requested = 0;
 
     if (Requested)
       MaxNumVGPRs = Requested;
   }
 
   return MaxNumVGPRs - getNumDebuggerReservedVGPRs(ST);
 }
+
+ArrayRef<int16_t> SIRegisterInfo::getRegSplitParts(const TargetRegisterClass *RC,
+                                                   unsigned EltSize) const {
+  if (EltSize == 4) {
+    static const int16_t Sub0_15[] = {
+      AMDGPU::sub0, AMDGPU::sub1, AMDGPU::sub2, AMDGPU::sub3,
+      AMDGPU::sub4, AMDGPU::sub5, AMDGPU::sub6, AMDGPU::sub7,
+      AMDGPU::sub8, AMDGPU::sub9, AMDGPU::sub10, AMDGPU::sub11,
+      AMDGPU::sub12, AMDGPU::sub13, AMDGPU::sub14, AMDGPU::sub15,
+    };
+
+    static const int16_t Sub0_7[] = {
+      AMDGPU::sub0, AMDGPU::sub1, AMDGPU::sub2, AMDGPU::sub3,
+      AMDGPU::sub4, AMDGPU::sub5, AMDGPU::sub6, AMDGPU::sub7,
+    };
+
+    static const int16_t Sub0_3[] = {
+      AMDGPU::sub0, AMDGPU::sub1, AMDGPU::sub2, AMDGPU::sub3,
+    };
+
+    static const int16_t Sub0_2[] = {
+      AMDGPU::sub0, AMDGPU::sub1, AMDGPU::sub2,
+    };
+
+    static const int16_t Sub0_1[] = {
+      AMDGPU::sub0, AMDGPU::sub1,
+    };
+
+    switch (RC->getSize()) {
+    case 4:
+      return {};
+    case 8:
+      return Sub0_1;
+    case 12:
+      return Sub0_2;
+    case 16:
+      return Sub0_3;
+    case 32:
+      return Sub0_7;
+    case 64:
+      return Sub0_15;
+    default:
+      llvm_unreachable("unhandled register size");
+    }
+  }
+
+  if (EltSize == 8) {
+    static const int16_t Sub0_15_64[] = {
+      AMDGPU::sub0_sub1, AMDGPU::sub2_sub3,
+      AMDGPU::sub4_sub5, AMDGPU::sub6_sub7,
+      AMDGPU::sub8_sub9, AMDGPU::sub10_sub11,
+      AMDGPU::sub12_sub13, AMDGPU::sub14_sub15
+    };
+
+    static const int16_t Sub0_7_64[] = {
+      AMDGPU::sub0_sub1, AMDGPU::sub2_sub3,
+      AMDGPU::sub4_sub5, AMDGPU::sub6_sub7
+    };
+
+
+    static const int16_t Sub0_3_64[] = {
+      AMDGPU::sub0_sub1, AMDGPU::sub2_sub3
+    };
+
+    switch (RC->getSize()) {
+    case 8:
+      return {};
+    case 16:
+      return Sub0_3_64;
+    case 32:
+      return Sub0_7_64;
+    case 64:
+      return Sub0_15_64;
+    default:
+      llvm_unreachable("unhandled register size");
+    }
+  }
+
+  assert(EltSize == 16 && "unhandled register spill split size");
+
+  static const int16_t Sub0_15_128[] = {
+    AMDGPU::sub0_sub1_sub2_sub3,
+    AMDGPU::sub4_sub5_sub6_sub7,
+    AMDGPU::sub8_sub9_sub10_sub11,
+    AMDGPU::sub12_sub13_sub14_sub15
+  };
+
+  static const int16_t Sub0_7_128[] = {
+    AMDGPU::sub0_sub1_sub2_sub3,
+    AMDGPU::sub4_sub5_sub6_sub7
+  };
+
+  switch (RC->getSize()) {
+  case 16:
+    return {};
+  case 32:
+    return Sub0_7_128;
+  case 64:
+    return Sub0_15_128;
+  default:
+    llvm_unreachable("unhandled register size");
+  }
+}