AMDGPU: Delete dead code

There is no context where s_mov_b64 is emitted
and could potentially be moved to the VALU.
It is currently only emitted for materializing
immediates, which can't be dependent on vector sources.

The immediate splitting is already done when selecting
constants. I'm not sure what contexts if any the register
splitting would have been used before.

Also clean up using s_mov_b64 in place of v_mov_b64_pseudo,
although this isn't required and just skips the extra step
of eliminating the copy from the SReg_64.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@246080 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/AMDGPU/SIInstrInfo.cpp b/lib/Target/AMDGPU/SIInstrInfo.cpp
index d6f70a6da46c01bcc9ed595b7002d3831baea25f..ff0770642409113bd213e63455c21f8858ce8891 100644 (file)
--- a/lib/Target/AMDGPU/SIInstrInfo.cpp
+++ b/lib/Target/AMDGPU/SIInstrInfo.cpp
@@ -1588,36 +1588,6 @@ MachineOperand SIInstrInfo::buildExtractSubRegOrImm(
   return MachineOperand::CreateReg(SubReg, false);
 }
 
-unsigned SIInstrInfo::split64BitImm(SmallVectorImpl<MachineInstr *> &Worklist,
-                                    MachineBasicBlock::iterator MI,
-                                    MachineRegisterInfo &MRI,
-                                    const TargetRegisterClass *RC,
-                                    const MachineOperand &Op) const {
-  MachineBasicBlock *MBB = MI->getParent();
-  DebugLoc DL = MI->getDebugLoc();
-  unsigned LoDst = MRI.createVirtualRegister(&AMDGPU::SGPR_32RegClass);
-  unsigned HiDst = MRI.createVirtualRegister(&AMDGPU::SGPR_32RegClass);
-  unsigned Dst = MRI.createVirtualRegister(RC);
-
-  MachineInstr *Lo = BuildMI(*MBB, MI, DL, get(AMDGPU::S_MOV_B32),
-                             LoDst)
-    .addImm(Op.getImm() & 0xFFFFFFFF);
-  MachineInstr *Hi = BuildMI(*MBB, MI, DL, get(AMDGPU::S_MOV_B32),
-                             HiDst)
-    .addImm(Op.getImm() >> 32);
-
-  BuildMI(*MBB, MI, DL, get(TargetOpcode::REG_SEQUENCE), Dst)
-    .addReg(LoDst)
-    .addImm(AMDGPU::sub0)
-    .addReg(HiDst)
-    .addImm(AMDGPU::sub1);
-
-  Worklist.push_back(Lo);
-  Worklist.push_back(Hi);
-
-  return Dst;
-}
-
 // Change the order of operands from (0, 1, 2) to (0, 2, 1)
 void SIInstrInfo::swapOperands(MachineBasicBlock::iterator Inst) const {
   assert(Inst->getNumExplicitOperands() == 3);
@@ -2170,30 +2140,6 @@ void SIInstrInfo::moveToVALU(MachineInstr &TopInst) const {
         moveSMRDToVALU(Inst, MRI);
       }
       break;
-    case AMDGPU::S_MOV_B64: {
-      DebugLoc DL = Inst->getDebugLoc();
-
-      // If the source operand is a register we can replace this with a
-      // copy.
-      if (Inst->getOperand(1).isReg()) {
-        MachineInstr *Copy = BuildMI(*MBB, Inst, DL, get(TargetOpcode::COPY))
-          .addOperand(Inst->getOperand(0))
-          .addOperand(Inst->getOperand(1));
-        Worklist.push_back(Copy);
-      } else {
-        // Otherwise, we need to split this into two movs, because there is
-        // no 64-bit VALU move instruction.
-        unsigned Reg = Inst->getOperand(0).getReg();
-        unsigned Dst = split64BitImm(Worklist,
-                                     Inst,
-                                     MRI,
-                                     MRI.getRegClass(Reg),
-                                     Inst->getOperand(1));
-        MRI.replaceRegWith(Reg, Dst);
-      }
-      Inst->eraseFromParent();
-      continue;
-    }
     case AMDGPU::S_AND_B64:
       splitScalar64BitBinaryOp(Worklist, Inst, AMDGPU::V_AND_B32_e64);
       Inst->eraseFromParent();

diff --git a/lib/Target/AMDGPU/SIInstrInfo.h b/lib/Target/AMDGPU/SIInstrInfo.h
index 7c1ab7fb4e3a9b8fee5fa630f3b8c237cbb04892..9b4ba029122aa483bdb6373545acd8f521cc0147 100644 (file)
--- a/lib/Target/AMDGPU/SIInstrInfo.h
+++ b/lib/Target/AMDGPU/SIInstrInfo.h
@@ -39,12 +39,6 @@ private:
                                          unsigned SubIdx,
                                          const TargetRegisterClass *SubRC) const;
 
-  unsigned split64BitImm(SmallVectorImpl<MachineInstr *> &Worklist,
-                         MachineBasicBlock::iterator MI,
-                         MachineRegisterInfo &MRI,
-                         const TargetRegisterClass *RC,
-                         const MachineOperand &Op) const;
-
   void swapOperands(MachineBasicBlock::iterator Inst) const;
 
   void splitScalar64BitUnaryOp(SmallVectorImpl<MachineInstr *> &Worklist,

diff --git a/lib/Target/AMDGPU/SIInstructions.td b/lib/Target/AMDGPU/SIInstructions.td
index 5c50580822f67a0325543fabb692e0a240d9b43f..0ba039d98dac5d0ee207f3eab274f0c64719e904 100644 (file)
--- a/lib/Target/AMDGPU/SIInstructions.td
+++ b/lib/Target/AMDGPU/SIInstructions.td
@@ -2817,10 +2817,6 @@ class DSAtomicRetPat<DS inst, ValueType vt, PatFrag frag> : Pat <
 // -1. For the non-rtn variants, the manual says it does
 // DS[A] = (DS[A] >= D0) ? 0 : DS[A] + 1, and setting D0 to uint_max
 // will always do the increment so I'm assuming it's the same.
-//
-// We also load this -1 with s_mov_b32 / s_mov_b64 even though this
-// needs to be a VGPR. The SGPR copy pass will fix this, and it's
-// easier since there is no v_mov_b64.
 class DSAtomicIncRetPat<DS inst, ValueType vt,
                         Instruction LoadImm, PatFrag frag> : Pat <
   (frag (DS1Addr1Offset i32:$ptr, i32:$offset), (vt 1)),
@@ -2836,9 +2832,9 @@ class DSAtomicCmpXChg <DS inst, ValueType vt, PatFrag frag> : Pat <
 
 // 32-bit atomics.
 def : DSAtomicIncRetPat<DS_INC_RTN_U32, i32,
-                        S_MOV_B32, si_atomic_load_add_local>;
+                        V_MOV_B32_e32, si_atomic_load_add_local>;
 def : DSAtomicIncRetPat<DS_DEC_RTN_U32, i32,
-                        S_MOV_B32, si_atomic_load_sub_local>;
+                        V_MOV_B32_e32, si_atomic_load_sub_local>;
 
 def : DSAtomicRetPat<DS_WRXCHG_RTN_B32, i32, si_atomic_swap_local>;
 def : DSAtomicRetPat<DS_ADD_RTN_U32, i32, si_atomic_load_add_local>;
@@ -2855,9 +2851,9 @@ def : DSAtomicCmpXChg<DS_CMPST_RTN_B32, i32, si_atomic_cmp_swap_32_local>;
 
 // 64-bit atomics.
 def : DSAtomicIncRetPat<DS_INC_RTN_U64, i64,
-                        S_MOV_B64, si_atomic_load_add_local>;
+                        V_MOV_B64_PSEUDO, si_atomic_load_add_local>;
 def : DSAtomicIncRetPat<DS_DEC_RTN_U64, i64,
-                        S_MOV_B64, si_atomic_load_sub_local>;
+                        V_MOV_B64_PSEUDO, si_atomic_load_sub_local>;
 
 def : DSAtomicRetPat<DS_WRXCHG_RTN_B64, i64, si_atomic_swap_local>;
 def : DSAtomicRetPat<DS_ADD_RTN_U64, i64, si_atomic_load_add_local>;