Use COPY_TO_REGCLASS instead of pseudo instructions for Neon FP patterns.

Jakob Olesen suggested that we can avoid the need for separate pseudo
instructions here by using COPY_TO_REGCLASS in the patterns.  The pattern
gets pretty ugly but it seems to work well.  Partial fix for Radar 8711675.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121718 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/ARM/ARMExpandPseudoInsts.cpp

@@ -54,7 +54,6 @@ namespace {
     void ExpandLaneOp(MachineBasicBlock::iterator &MBBI);
     void ExpandVTBL(MachineBasicBlock::iterator &MBBI,
                     unsigned Opc, bool IsExt, unsigned NumRegs);
-    void ExpandNeonSFP2(MachineBasicBlock::iterator &MBBI, unsigned Opc);
   };
   char ARMExpandPseudo::ID = 0;
 }
@@ -613,21 +612,6 @@ void ARMExpandPseudo::ExpandVTBL(MachineBasicBlock::iterator &MBBI,
   MI.eraseFromParent();
 }
 
-/// ExpandNeonSFP2 - Translate a 2-register Neon pseudo instruction used for
-/// scalar floating-point to a real instruction.
-void ARMExpandPseudo::ExpandNeonSFP2(MachineBasicBlock::iterator &MBBI,
-                                     unsigned Opc) {
-  MachineInstr &MI = *MBBI;
-  MachineBasicBlock &MBB = *MI.getParent();
-  MachineInstrBuilder MIB = BuildMI(MBB, MBBI, MI.getDebugLoc(), TII->get(Opc));
-  MIB.addOperand(MI.getOperand(0)) // destination register
-    .addOperand(MI.getOperand(1))  // source register
-    .addOperand(MI.getOperand(2))  // predicate
-    .addOperand(MI.getOperand(3)); // predicate register
-  TransferImpOps(MI, MIB, MIB);
-  MI.eraseFromParent();
-}
-
 bool ARMExpandPseudo::ExpandMBB(MachineBasicBlock &MBB) {
   bool Modified = false;
 
@@ -1167,13 +1151,6 @@ bool ARMExpandPseudo::ExpandMBB(MachineBasicBlock &MBB) {
     case ARM::VTBX2Pseudo: ExpandVTBL(MBBI, ARM::VTBX2, true, 2); break;
     case ARM::VTBX3Pseudo: ExpandVTBL(MBBI, ARM::VTBX3, true, 3); break;
     case ARM::VTBX4Pseudo: ExpandVTBL(MBBI, ARM::VTBX4, true, 4); break;
-
-    case ARM::VABSfd_sfp:   ExpandNeonSFP2(MBBI, ARM::VABSfd); break;
-    case ARM::VNEGfd_sfp:   ExpandNeonSFP2(MBBI, ARM::VNEGfd); break;
-    case ARM::VCVTf2sd_sfp: ExpandNeonSFP2(MBBI, ARM::VCVTf2sd); break;
-    case ARM::VCVTf2ud_sfp: ExpandNeonSFP2(MBBI, ARM::VCVTf2ud); break;
-    case ARM::VCVTs2fd_sfp: ExpandNeonSFP2(MBBI, ARM::VCVTs2fd); break;
-    case ARM::VCVTu2fd_sfp: ExpandNeonSFP2(MBBI, ARM::VCVTu2fd); break;
     }
 
     if (ModifiedOp)

lib/Target/ARM/ARMInstrNEON.td

@@ -1669,8 +1669,6 @@ def SubReg_i32_lane : SDNodeXForm<imm, [{
 
 // Basic 2-register operations: single-, double- and quad-register.
 let neverHasSideEffects = 1 in
-class N2VS
-  : PseudoNeonI<(outs DPR_VFP2:$Vd), (ins DPR_VFP2:$Vm), IIC_VUNAD, "", []>;
 class N2VD<bits<2> op24_23, bits<2> op21_20, bits<2> op19_18,
            bits<2> op17_16, bits<5> op11_7, bit op4, string OpcodeStr,
            string Dt, ValueType ResTy, ValueType OpTy, SDNode OpNode>
@@ -4678,11 +4676,14 @@ def  VTBX4Pseudo
 // NEON instructions for single-precision FP math
 //===----------------------------------------------------------------------===//
 
-class N2VSPat<SDNode OpNode, ValueType ResTy, ValueType OpTy, PseudoNeonI Inst>
+class N2VSPat<SDNode OpNode, ValueType ResTy, ValueType OpTy, NeonI Inst>
   : NEONFPPat<(ResTy (OpNode SPR:$a)),
-              (EXTRACT_SUBREG (OpTy (Inst (INSERT_SUBREG (OpTy (IMPLICIT_DEF)),
+              (EXTRACT_SUBREG
-                                                       SPR:$a, ssub_0))),
+               (OpTy (COPY_TO_REGCLASS
-                              ssub_0)>;
+                (OpTy (Inst (INSERT_SUBREG
+                 (OpTy (COPY_TO_REGCLASS (OpTy (IMPLICIT_DEF)), DPR_VFP2)),
+                                           SPR:$a, ssub_0))),
+                                       DPR_VFP2)), ssub_0)>;
 
 class N3VSPat<SDNode OpNode, NeonI Inst>
   : NEONFPPat<(f32 (OpNode SPR:$a, SPR:$b)),
@@ -4736,12 +4737,10 @@ def : N3VSMulOpPat<fmul, fsub, VMLSfd_sfp>,
       Requires<[HasNEON, UseNEONForFP, UseFPVMLx]>;
 
 // Vector Absolute used for single-precision FP
-def  VABSfd_sfp : N2VS;
+def : N2VSPat<fabs, f32, v2f32, VABSfd>;
-def : N2VSPat<fabs, f32, v2f32, VABSfd_sfp>;
 
 // Vector Negate used for single-precision FP
-def  VNEGfd_sfp : N2VS;
+def : N2VSPat<fneg, f32, v2f32, VNEGfd>;
-def : N2VSPat<fneg, f32, v2f32, VNEGfd_sfp>;
 
 // Vector Maximum used for single-precision FP
 let neverHasSideEffects = 1 in
@@ -4758,17 +4757,10 @@ def VMINfd_sfp : N3V<0, 0, 0b10, 0b1111, 0, 0, (outs DPR_VFP2:$Vd),
 def : N3VSPat<NEONfmin, VMINfd_sfp>;
 
 // Vector Convert between single-precision FP and integer
-def  VCVTf2sd_sfp : N2VS;
+def : N2VSPat<arm_ftosi, f32, v2f32, VCVTf2sd>;
-def : N2VSPat<arm_ftosi, f32, v2f32, VCVTf2sd_sfp>;
+def : N2VSPat<arm_ftoui, f32, v2f32, VCVTf2ud>;
-
+def : N2VSPat<arm_sitof, f32, v2i32, VCVTs2fd>;
-def  VCVTf2ud_sfp : N2VS;
+def : N2VSPat<arm_uitof, f32, v2i32, VCVTu2fd>;
-def : N2VSPat<arm_ftoui, f32, v2f32, VCVTf2ud_sfp>;
-
-def  VCVTs2fd_sfp : N2VS;
-def : N2VSPat<arm_sitof, f32, v2i32, VCVTs2fd_sfp>;
-
-def  VCVTu2fd_sfp : N2VS;
-def : N2VSPat<arm_uitof, f32, v2i32, VCVTu2fd_sfp>;
 
 //===----------------------------------------------------------------------===//
 // Non-Instruction Patterns