Use NEON reg-reg moves, where profitable. This reduces "domain-cross" stalls, when we used to mix vfp and neon code (the former were used for reg-reg moves)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85764 91177308-0d34-0410-b5e6-96231b3b80d8

8 files changed, 97 insertions, 31 deletions

diff --git a/lib/Target/ARM/ARM.td b/lib/Target/ARM/ARM.td
index 8851fbbf24..cb9bd6a094 100644
--- a/lib/Target/ARM/ARM.td
+++ b/lib/Target/ARM/ARM.td
@@ -125,12 +125,16 @@ def ARMInstrInfo : InstrInfo {
                        "SizeFlag",
                        "IndexModeBits",
                        "Form",
-                       "isUnaryDataProc"];
+                       "isUnaryDataProc",
+                       "canXformTo16Bit",
+                       "Dom"];
   let TSFlagsShifts = [0,
                        4,
                        7,
                        9,
-                       15];
+                       15,
+                       16,
+                       17];
 }
 
 //===----------------------------------------------------------------------===//
diff --git a/lib/Target/ARM/ARMBaseInstrInfo.cpp b/lib/Target/ARM/ARMBaseInstrInfo.cpp
index 6b031da143..4cb2407aeb 100644
--- a/lib/Target/ARM/ARMBaseInstrInfo.cpp
+++ b/lib/Target/ARM/ARMBaseInstrInfo.cpp
@@ -16,15 +16,18 @@
 #include "ARMAddressingModes.h"
 #include "ARMGenInstrInfo.inc"
 #include "ARMMachineFunctionInfo.h"
+#include "ARMRegisterInfo.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/CodeGen/LiveVariables.h"
 #include "llvm/CodeGen/MachineFrameInfo.h"
 #include "llvm/CodeGen/MachineInstrBuilder.h"
 #include "llvm/CodeGen/MachineJumpTableInfo.h"
 #include "llvm/CodeGen/MachineMemOperand.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
 #include "llvm/CodeGen/PseudoSourceValue.h"
 #include "llvm/MC/MCAsmInfo.h"
 #include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Debug.h"
 #include "llvm/Support/ErrorHandling.h"
 using namespace llvm;
 
@@ -32,8 +35,9 @@ static cl::opt<bool>
 EnableARM3Addr("enable-arm-3-addr-conv", cl::Hidden,
                cl::desc("Enable ARM 2-addr to 3-addr conv"));
 
-ARMBaseInstrInfo::ARMBaseInstrInfo()
-  : TargetInstrInfoImpl(ARMInsts, array_lengthof(ARMInsts)) {
+ARMBaseInstrInfo::ARMBaseInstrInfo(const ARMSubtarget& STI)
+  : TargetInstrInfoImpl(ARMInsts, array_lengthof(ARMInsts)),
+    Subtarget(STI) {
 }
 
 MachineInstr *
@@ -504,7 +508,7 @@ ARMBaseInstrInfo::isMoveInstr(const MachineInstr &MI,
   case ARM::FCPYS:
   case ARM::FCPYD:
   case ARM::VMOVD:
-  case  ARM::VMOVQ: {
+  case ARM::VMOVQ: {
     SrcReg = MI.getOperand(1).getReg();
     DstReg = MI.getOperand(0).getReg();
     return true;
@@ -647,11 +651,45 @@ ARMBaseInstrInfo::copyRegToReg(MachineBasicBlock &MBB,
   } else if (DestRC == ARM::SPRRegisterClass) {
     AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::FCPYS), DestReg)
                    .addReg(SrcReg));
-  } else if ((DestRC == ARM::DPRRegisterClass) ||
-             (DestRC == ARM::DPR_VFP2RegisterClass) ||
-             (DestRC == ARM::DPR_8RegisterClass)) {
-    AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::FCPYD), DestReg)
-                   .addReg(SrcReg));
+  } else if (DestRC == ARM::DPR_VFP2RegisterClass ||
+             DestRC == ARM::DPR_8RegisterClass ||
+             SrcRC == ARM::DPR_VFP2RegisterClass ||
+             SrcRC == ARM::DPR_8RegisterClass) {
+    // Always use neon reg-reg move if source or dest is NEON-only regclass.
+    BuildMI(MBB, I, DL, get(ARM::VMOVD), DestReg).addReg(SrcReg);
+  } else if (DestRC == ARM::DPRRegisterClass) {
+    const ARMBaseRegisterInfo* TRI = &getRegisterInfo();
+
+    // Find the Machine Instruction which defines SrcReg.
+    MachineBasicBlock::iterator J = (I == MBB.begin() ? I : prior(I));
+    while (J != MBB.begin()) {
+      if (J->modifiesRegister(SrcReg, TRI))
+        break;
+      --J;
+    }
+
+    unsigned Domain;
+    if (J->modifiesRegister(SrcReg, TRI)) {
+      Domain = J->getDesc().TSFlags & ARMII::DomainMask;
+      // Instructions in general domain are subreg accesses.
+      // Map them to NEON reg-reg moves.
+      if (Domain == ARMII::DomainGeneral)
+        Domain = ARMII::DomainNEON;
+    } else {
+      // We reached the beginning of the BB and found no instruction defining
+      // the reg. This means that register should be live-in for this BB.
+      // It's always to better to use NEON reg-reg moves.
+      Domain = ARMII::DomainNEON;
+    }
+
+    if ((Domain & ARMII::DomainNEON) && getSubtarget().hasNEON()) {
+      BuildMI(MBB, I, DL, get(ARM::VMOVQ), DestReg).addReg(SrcReg);
+    } else {
+      assert((Domain & ARMII::DomainVFP ||
+              !getSubtarget().hasNEON()) && "Invalid domain!");
+      AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::FCPYD), DestReg)
+                     .addReg(SrcReg));
+    }
   } else if (DestRC == ARM::QPRRegisterClass ||
              DestRC == ARM::QPR_VFP2RegisterClass) {
     BuildMI(MBB, I, DL, get(ARM::VMOVQ), DestReg).addReg(SrcReg);
diff --git a/lib/Target/ARM/ARMBaseInstrInfo.h b/lib/Target/ARM/ARMBaseInstrInfo.h
index acb7fdd9f1..2ba377474e 100644
--- a/lib/Target/ARM/ARMBaseInstrInfo.h
+++ b/lib/Target/ARM/ARMBaseInstrInfo.h
@@ -131,6 +131,14 @@ namespace ARMII {
     Xform16Bit    = 1 << 16,
 
     //===------------------------------------------------------------------===//
+    // Code domain.
+    DomainShift   = 17,
+    DomainMask    = 3 << DomainShift,
+    DomainGeneral = 0 << DomainShift,
+    DomainVFP     = 1 << DomainShift,
+    DomainNEON    = 2 << DomainShift,
+
+    //===------------------------------------------------------------------===//
     // Field shifts - such shifts are used to set field while generating
     // machine instructions.
     M_BitShift     = 5,
@@ -157,9 +165,10 @@ namespace ARMII {
 }
 
 class ARMBaseInstrInfo : public TargetInstrInfoImpl {
+  const ARMSubtarget& Subtarget;
 protected:
   // Can be only subclassed.
-  explicit ARMBaseInstrInfo();
+  explicit ARMBaseInstrInfo(const ARMSubtarget &STI);
 public:
   // Return the non-pre/post incrementing version of 'Opc'. Return 0
   // if there is not such an opcode.
@@ -173,6 +182,7 @@ public:
                                               LiveVariables *LV) const;
 
   virtual const ARMBaseRegisterInfo &getRegisterInfo() const =0;
+  const ARMSubtarget &getSubtarget() const { return Subtarget; }
 
   // Branch analysis.
   virtual bool AnalyzeBranch(MachineBasicBlock &MBB, MachineBasicBlock *&TBB,
diff --git a/lib/Target/ARM/ARMInstrFormats.td b/lib/Target/ARM/ARMInstrFormats.td
index 1c351e379e..1a42d0e0d9 100644
--- a/lib/Target/ARM/ARMInstrFormats.td
+++ b/lib/Target/ARM/ARMInstrFormats.td
@@ -108,6 +108,15 @@ def IndexModeNone : IndexMode<0>;
 def IndexModePre  : IndexMode<1>;
 def IndexModePost : IndexMode<2>;
 
+// Instruction execution domain.
+class Domain<bits<2> val> {
+  bits<2> Value = val;
+}
+def GenericDomain : Domain<0>;
+def VFPDomain     : Domain<1>; // Instructions in VFP domain only
+def NeonDomain    : Domain<2>; // Instructions in Neon domain only
+def VFPNeonDomain : Domain<3>; // Instructions in both VFP & Neon domains
+
 //===----------------------------------------------------------------------===//
 
 // ARM special operands.
@@ -136,7 +145,7 @@ def s_cc_out : OptionalDefOperand<OtherVT, (ops CCR), (ops (i32 CPSR))> {
 //
 
 class InstARM<AddrMode am, SizeFlagVal sz, IndexMode im,
-              Format f, string cstr, InstrItinClass itin>
+              Format f, Domain d, string cstr, InstrItinClass itin>
   : Instruction {
   field bits<32> Inst;
 
@@ -155,6 +164,9 @@ class InstARM<AddrMode am, SizeFlagVal sz, IndexMode im,
   Format F = f;
   bits<5> Form = F.Value;
 
+  Domain D = d;
+  bits<2> Dom = D.Value;
+
   //
   // Attributes specific to ARM instructions...
   //
@@ -167,7 +179,8 @@ class InstARM<AddrMode am, SizeFlagVal sz, IndexMode im,
 
 class PseudoInst<dag oops, dag iops, InstrItinClass itin, 
                  string asm, list<dag> pattern>
-  : InstARM<AddrModeNone, SizeSpecial, IndexModeNone, Pseudo, "", itin> {
+  : InstARM<AddrModeNone, SizeSpecial, IndexModeNone, Pseudo, GenericDomain, 
+            "", itin> {
   let OutOperandList = oops;
   let InOperandList = iops;
   let AsmString   = asm;
@@ -179,7 +192,7 @@ class I<dag oops, dag iops, AddrMode am, SizeFlagVal sz,
         IndexMode im, Format f, InstrItinClass itin, 
         string opc, string asm, string cstr,
         list<dag> pattern>
-  : InstARM<am, sz, im, f, cstr, itin> {
+  : InstARM<am, sz, im, f, GenericDomain, cstr, itin> {
   let OutOperandList = oops;
   let InOperandList = !con(iops, (ops pred:$p));
   let AsmString   = !strconcat(opc, !strconcat("${p}", asm));
@@ -194,7 +207,7 @@ class sI<dag oops, dag iops, AddrMode am, SizeFlagVal sz,
          IndexMode im, Format f, InstrItinClass itin,
          string opc, string asm, string cstr,
          list<dag> pattern>
-  : InstARM<am, sz, im, f, cstr, itin> {
+  : InstARM<am, sz, im, f, GenericDomain, cstr, itin> {
   let OutOperandList = oops;
   let InOperandList = !con(iops, (ops pred:$p, cc_out:$s));
   let AsmString   = !strconcat(opc, !strconcat("${p}${s}", asm));
@@ -206,7 +219,7 @@ class sI<dag oops, dag iops, AddrMode am, SizeFlagVal sz,
 class XI<dag oops, dag iops, AddrMode am, SizeFlagVal sz,
          IndexMode im, Format f, InstrItinClass itin,
          string asm, string cstr, list<dag> pattern>
-  : InstARM<am, sz, im, f, cstr, itin> {
+  : InstARM<am, sz, im, f, GenericDomain, cstr, itin> {
   let OutOperandList = oops;
   let InOperandList = iops;
   let AsmString   = asm;
@@ -807,7 +820,7 @@ class ARMV6Pat<dag pattern, dag result> : Pat<pattern, result> {
 
 class ThumbI<dag oops, dag iops, AddrMode am, SizeFlagVal sz,
              InstrItinClass itin, string asm, string cstr, list<dag> pattern>
-  : InstARM<am, sz, IndexModeNone, ThumbFrm, cstr, itin> {
+  : InstARM<am, sz, IndexModeNone, ThumbFrm, GenericDomain, cstr, itin> {
   let OutOperandList = oops;
   let InOperandList = iops;
   let AsmString   = asm;
@@ -833,7 +846,7 @@ class TJTI<dag oops, dag iops, InstrItinClass itin, string asm, list<dag> patter
 // Thumb1 only
 class Thumb1I<dag oops, dag iops, AddrMode am, SizeFlagVal sz,
               InstrItinClass itin, string asm, string cstr, list<dag> pattern>
-  : InstARM<am, sz, IndexModeNone, ThumbFrm, cstr, itin> {
+  : InstARM<am, sz, IndexModeNone, ThumbFrm, GenericDomain, cstr, itin> {
   let OutOperandList = oops;
   let InOperandList = iops;
   let AsmString   = asm;
@@ -861,7 +874,7 @@ class T1It<dag oops, dag iops, InstrItinClass itin,
 class Thumb1sI<dag oops, dag iops, AddrMode am, SizeFlagVal sz,
                InstrItinClass itin,
                string opc, string asm, string cstr, list<dag> pattern>
-  : InstARM<am, sz, IndexModeNone, ThumbFrm, cstr, itin> {
+  : InstARM<am, sz, IndexModeNone, ThumbFrm, GenericDomain, cstr, itin> {
   let OutOperandList = !con(oops, (ops s_cc_out:$s));
   let InOperandList = !con(iops, (ops pred:$p));
   let AsmString = !strconcat(opc, !strconcat("${s}${p}", asm));
@@ -883,7 +896,7 @@ class T1sIt<dag oops, dag iops, InstrItinClass itin,
 class Thumb1pI<dag oops, dag iops, AddrMode am, SizeFlagVal sz,
                InstrItinClass itin,
                string opc, string asm, string cstr, list<dag> pattern>
-  : InstARM<am, sz, IndexModeNone, ThumbFrm, cstr, itin> {
+  : InstARM<am, sz, IndexModeNone, ThumbFrm, GenericDomain, cstr, itin> {
   let OutOperandList = oops;
   let InOperandList = !con(iops, (ops pred:$p));
   let AsmString = !strconcat(opc, !strconcat("${p}", asm));
@@ -918,7 +931,7 @@ class T1pIs<dag oops, dag iops,
 class Thumb2I<dag oops, dag iops, AddrMode am, SizeFlagVal sz,
               InstrItinClass itin,
               string opc, string asm, string cstr, list<dag> pattern>
-  : InstARM<am, sz, IndexModeNone, ThumbFrm, cstr, itin> {
+  : InstARM<am, sz, IndexModeNone, ThumbFrm, GenericDomain, cstr, itin> {
   let OutOperandList = oops;
   let InOperandList = !con(iops, (ops pred:$p));
   let AsmString = !strconcat(opc, !strconcat("${p}", asm));
@@ -934,7 +947,7 @@ class Thumb2I<dag oops, dag iops, AddrMode am, SizeFlagVal sz,
 class Thumb2sI<dag oops, dag iops, AddrMode am, SizeFlagVal sz,
                InstrItinClass itin,
                string opc, string asm, string cstr, list<dag> pattern>
-  : InstARM<am, sz, IndexModeNone, ThumbFrm, cstr, itin> {
+  : InstARM<am, sz, IndexModeNone, ThumbFrm, GenericDomain, cstr, itin> {
   let OutOperandList = oops;
   let InOperandList = !con(iops, (ops pred:$p, cc_out:$s));
   let AsmString   = !strconcat(opc, !strconcat("${s}${p}", asm));
@@ -946,7 +959,7 @@ class Thumb2sI<dag oops, dag iops, AddrMode am, SizeFlagVal sz,
 class Thumb2XI<dag oops, dag iops, AddrMode am, SizeFlagVal sz,
                InstrItinClass itin,
                string asm, string cstr, list<dag> pattern>
-  : InstARM<am, sz, IndexModeNone, ThumbFrm, cstr, itin> {
+  : InstARM<am, sz, IndexModeNone, ThumbFrm, GenericDomain, cstr, itin> {
   let OutOperandList = oops;
   let InOperandList = iops;
   let AsmString   = asm;
@@ -993,7 +1006,7 @@ class T2Ix2<dag oops, dag iops, InstrItinClass itin,
 class T2Iidxldst<dag oops, dag iops, AddrMode am, IndexMode im,
                  InstrItinClass itin,
                  string opc, string asm, string cstr, list<dag> pattern>
-  : InstARM<am, Size4Bytes, im, ThumbFrm, cstr, itin> {
+  : InstARM<am, Size4Bytes, im, ThumbFrm, GenericDomain, cstr, itin> {
   let OutOperandList = oops;
   let InOperandList = !con(iops, (ops pred:$p));
   let AsmString = !strconcat(opc, !strconcat("${p}", asm));
@@ -1026,7 +1039,7 @@ class T2Pat<dag pattern, dag result> : Pat<pattern, result> {
 class VFPI<dag oops, dag iops, AddrMode am, SizeFlagVal sz,
            IndexMode im, Format f, InstrItinClass itin,
            string opc, string asm, string cstr, list<dag> pattern>
-  : InstARM<am, sz, im, f, cstr, itin> {
+  : InstARM<am, sz, im, f, VFPDomain, cstr, itin> {
   let OutOperandList = oops;
   let InOperandList = !con(iops, (ops pred:$p));
   let AsmString   = !strconcat(opc, !strconcat("${p}", asm));
@@ -1038,7 +1051,7 @@ class VFPI<dag oops, dag iops, AddrMode am, SizeFlagVal sz,
 class VFPXI<dag oops, dag iops, AddrMode am, SizeFlagVal sz,
             IndexMode im, Format f, InstrItinClass itin,
             string asm, string cstr, list<dag> pattern>
-  : InstARM<am, sz, im, f, cstr, itin> {
+  : InstARM<am, sz, im, f, VFPDomain, cstr, itin> {
   let OutOperandList = oops;
   let InOperandList = iops;
   let AsmString   = asm;
@@ -1199,7 +1212,7 @@ class AVConv5I<bits<8> opcod1, bits<4> opcod2, dag oops, dag iops,
 
 class NeonI<dag oops, dag iops, AddrMode am, IndexMode im, InstrItinClass itin,
             string asm, string cstr, list<dag> pattern>
-  : InstARM<am, Size4Bytes, im, NEONFrm, cstr, itin> {
+  : InstARM<am, Size4Bytes, im, NEONFrm, NeonDomain, cstr, itin> {
   let OutOperandList = oops;
   let InOperandList = iops;
   let AsmString = asm;
diff --git a/lib/Target/ARM/ARMInstrInfo.cpp b/lib/Target/ARM/ARMInstrInfo.cpp
index c24c690f25..86bbe2a4c6 100644
--- a/lib/Target/ARM/ARMInstrInfo.cpp
+++ b/lib/Target/ARM/ARMInstrInfo.cpp
@@ -25,7 +25,7 @@
 using namespace llvm;
 
 ARMInstrInfo::ARMInstrInfo(const ARMSubtarget &STI)
-  : RI(*this, STI), Subtarget(STI) {
+  : ARMBaseInstrInfo(STI), RI(*this, STI) {
 }
 
 unsigned ARMInstrInfo::getUnindexedOpcode(unsigned Opc) const {
diff --git a/lib/Target/ARM/ARMInstrInfo.h b/lib/Target/ARM/ARMInstrInfo.h
index c616949e37..5d1678d685 100644
--- a/lib/Target/ARM/ARMInstrInfo.h
+++ b/lib/Target/ARM/ARMInstrInfo.h
@@ -25,7 +25,6 @@ namespace llvm {
 
 class ARMInstrInfo : public ARMBaseInstrInfo {
   ARMRegisterInfo RI;
-  const ARMSubtarget &Subtarget;
 public:
   explicit ARMInstrInfo(const ARMSubtarget &STI);
 
diff --git a/lib/Target/ARM/Thumb1InstrInfo.cpp b/lib/Target/ARM/Thumb1InstrInfo.cpp
index 6943036e45..b6dd56c7ab 100644
--- a/lib/Target/ARM/Thumb1InstrInfo.cpp
+++ b/lib/Target/ARM/Thumb1InstrInfo.cpp
@@ -24,7 +24,8 @@
 
 using namespace llvm;
 
-Thumb1InstrInfo::Thumb1InstrInfo(const ARMSubtarget &STI) : RI(*this, STI) {
+Thumb1InstrInfo::Thumb1InstrInfo(const ARMSubtarget &STI)
+  : ARMBaseInstrInfo(STI), RI(*this, STI) {
 }
 
 unsigned Thumb1InstrInfo::getUnindexedOpcode(unsigned Opc) const {
diff --git a/lib/Target/ARM/Thumb2InstrInfo.cpp b/lib/Target/ARM/Thumb2InstrInfo.cpp
index 3ec147f266..21fff51cb7 100644
--- a/lib/Target/ARM/Thumb2InstrInfo.cpp
+++ b/lib/Target/ARM/Thumb2InstrInfo.cpp
@@ -25,7 +25,8 @@
 
 using namespace llvm;
 
-Thumb2InstrInfo::Thumb2InstrInfo(const ARMSubtarget &STI) : RI(*this, STI) {
+Thumb2InstrInfo::Thumb2InstrInfo(const ARMSubtarget &STI)
+  : ARMBaseInstrInfo(STI), RI(*this, STI) {
 }
 
 unsigned Thumb2InstrInfo::getUnindexedOpcode(unsigned Opc) const {