[mips] Fold FeatureBitCount into FeatureMips32 and FeatureMips64

[dsanders]

Summary

DCL[ZO] are now correctly marked as being MIPS64 instructions. This has no
effect on the CodeGen tests since expansion of i64 prevented their use
anyway.

The check for MIPS16 to prevent the use of CLZ no longer prevents DCLZ as
well. This is not a functional change since DCLZ is still prohibited by
being a MIPS64 instruction (MIPS16 is only compatible with MIPS32).

No functional change

[vmedic]

LGTM

lib/Target/Mips/MicroMipsInstrInfo.td

let DecoderNamespace = "MicroMips", Predicates = [InMicroMips] in {
 
   /// Multiply Add/Sub Instructions
   def MADD_MM  : MMRel, MArithR<"madd", II_MADD, 1>, MULT_FM_MM<0x32c>;
   def MADDU_MM : MMRel, MArithR<"maddu", II_MADDU, 1>, MULT_FM_MM<0x36c>;
   def MSUB_MM  : MMRel, MArithR<"msub", II_MSUB>, MULT_FM_MM<0x3ac>;
   def MSUBU_MM : MMRel, MArithR<"msubu", II_MSUBU>, MULT_FM_MM<0x3ec>;
 
   /// Count Leading
-  def CLZ_MM : MMRel, CountLeading0<"clz", GPR32Opnd>, CLO_FM_MM<0x16c>;
-  def CLO_MM : MMRel, CountLeading1<"clo", GPR32Opnd>, CLO_FM_MM<0x12c>;
+  def CLZ_MM : MMRel, CountLeading0<"clz", GPR32Opnd>, CLO_FM_MM<0x16c>,
+               ISA_MIPS32;
+  def CLO_MM : MMRel, CountLeading1<"clo", GPR32Opnd>, CLO_FM_MM<0x12c>,
+               ISA_MIPS32;
 
   /// Sign Ext In Register Instructions.
   def SEB_MM : MMRel, SignExtInReg<"seb", i8, GPR32Opnd, II_SEB>,
                SEB_FM_MM<0x0ac>, ISA_MIPS32R2;
   def SEH_MM : MMRel, SignExtInReg<"seh", i16, GPR32Opnd, II_SEH>,
                SEB_FM_MM<0x0ec>, ISA_MIPS32R2;
 
   /// Word Swap Bytes Within Halfwords

lib/Target/Mips/Mips.td

 def FeatureN32         : SubtargetFeature<"n32", "MipsABI", "N32",
                                 "Enable n32 ABI">;
 def FeatureN64         : SubtargetFeature<"n64", "MipsABI", "N64",
                                 "Enable n64 ABI">;
 def FeatureEABI        : SubtargetFeature<"eabi", "MipsABI", "EABI",
                                 "Enable eabi ABI">;
 def FeatureVFPU        : SubtargetFeature<"vfpu", "HasVFPU",
                                 "true", "Enable vector FPU instructions.">;
-def FeatureBitCount    : SubtargetFeature<"bitcount", "HasBitCount", "true",
-                                "Enable 'count leading bits' instructions.">;
 def FeatureMips1       : SubtargetFeature<"mips1", "MipsArchVersion", "Mips1",
                                 "Mips I ISA Support [highly experimental]">;
 def FeatureMips2       : SubtargetFeature<"mips2", "MipsArchVersion", "Mips2",
                                 "Mips II ISA Support [highly experimental]",
                                 [FeatureMips1]>;
 def FeatureMips3_32    : SubtargetFeature<"mips3_32", "HasMips3_32", "true",
                                 "Subset of MIPS-III that is also in MIPS32 "
                                 "[highly experimental]">;
def FeatureMips4       : SubtargetFeature<"mips4", "MipsArchVersion",
                                 [FeatureMips3, FeatureMips4_32,
                                  FeatureMips4_32r2]>;
 def FeatureMips5       : SubtargetFeature<"mips5", "MipsArchVersion", "Mips5",
                                 "MIPS V ISA Support [highly experimental]",
                                 [FeatureMips4]>;
 def FeatureMips32      : SubtargetFeature<"mips32", "MipsArchVersion", "Mips32",
                                 "Mips32 ISA Support",
                                 [FeatureMips2, FeatureMips3_32,
-                                 FeatureMips4_32, FeatureBitCount]>;
+                                 FeatureMips4_32]>;
 def FeatureMips32r2    : SubtargetFeature<"mips32r2", "MipsArchVersion",
                                 "Mips32r2", "Mips32r2 ISA Support",
                                 [FeatureMips4_32r2, FeatureMips32]>;
 def FeatureMips32r6    : SubtargetFeature<"mips32r6", "MipsArchVersion",
                                 "Mips32r6",
                                 "Mips32r6 ISA Support [experimental]",
                                 [FeatureMips32r2, FeatureFP64Bit,
                                  FeatureNaN2008]>;

lib/Target/Mips/Mips64InstrInfo.td

 /// Sign Ext In Register Instructions.
 def SEB64 : SignExtInReg<"seb", i8, GPR64Opnd, II_SEB>, SEB_FM<0x10, 0x20>,
             ISA_MIPS32R2;
 def SEH64 : SignExtInReg<"seh", i16, GPR64Opnd, II_SEH>, SEB_FM<0x18, 0x20>,
             ISA_MIPS32R2;
 }
 
 /// Count Leading
-def DCLZ : CountLeading0<"dclz", GPR64Opnd>, CLO_FM<0x24>;
-def DCLO : CountLeading1<"dclo", GPR64Opnd>, CLO_FM<0x25>;
+def DCLZ : CountLeading0<"dclz", GPR64Opnd>, CLO_FM<0x24>, ISA_MIPS64;
+def DCLO : CountLeading1<"dclo", GPR64Opnd>, CLO_FM<0x25>, ISA_MIPS64;
 
 /// Double Word Swap Bytes/HalfWords
 def DSBH : SubwordSwap<"dsbh", GPR64Opnd>, SEB_FM<2, 0x24>, ISA_MIPS64R2;
 def DSHD : SubwordSwap<"dshd", GPR64Opnd>, SEB_FM<5, 0x24>, ISA_MIPS64R2;
 
 def LEA_ADDiu64 : EffectiveAddress<"daddiu", GPR64Opnd>, LW_FM<0x19>;
 
 let isCodeGenOnly = 1 in

lib/Target/Mips/MipsISelLowering.cpp

MipsTargetLowering::MipsTargetLowering(MipsTargetMachine &TM)
 
   setInsertFencesForAtomic(true);
 
   if (!Subtarget->hasMips32r2()) {
     setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i8,  Expand);
     setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i16, Expand);
   }
 
-  if (!Subtarget->hasBitCount()) {
+  // MIPS16 lacks MIPS32's clz and clo instructions.
+  if (!Subtarget->hasMips32() || Subtarget->inMips16Mode())
     setOperationAction(ISD::CTLZ, MVT::i32, Expand);
+  if (!Subtarget->hasMips64())
     setOperationAction(ISD::CTLZ, MVT::i64, Expand);
-  }
 
   if (!Subtarget->hasMips32r2())
     setOperationAction(ISD::BSWAP, MVT::i32, Expand);
   if (!Subtarget->hasMips64r2())
     setOperationAction(ISD::BSWAP, MVT::i64, Expand);
 
   if (isGP64bit()) {
     setLoadExtAction(ISD::SEXTLOAD, MVT::i32, Custom);

lib/Target/Mips/MipsInstrInfo.td

 def MipsSDL : SDNode<"MipsISD::SDL", SDTStore,
                      [SDNPHasChain, SDNPMayStore, SDNPMemOperand]>;
 def MipsSDR : SDNode<"MipsISD::SDR", SDTStore,
                      [SDNPHasChain, SDNPMayStore, SDNPMemOperand]>;
 
 //===----------------------------------------------------------------------===//
 // Mips Instruction Predicate Definitions.
 //===----------------------------------------------------------------------===//
-def HasBitCount :     Predicate<"Subtarget.hasBitCount()">,
-                      AssemblerPredicate<"FeatureBitCount">;
 def HasMips2     :    Predicate<"Subtarget.hasMips2()">,
                       AssemblerPredicate<"FeatureMips2">;
 def HasMips3_32  :    Predicate<"Subtarget.hasMips3_32()">,
                       AssemblerPredicate<"FeatureMips3_32">;
 def HasMips3     :    Predicate<"Subtarget.hasMips3()">,
                       AssemblerPredicate<"FeatureMips3">;
 def HasMips4_32  :    Predicate<"Subtarget.hasMips4_32()">,
                       AssemblerPredicate<"FeatureMips4_32">;

 
 //===----------------------------------------------------------------------===//
 // Mips ISA/ASE membership and instruction group membership adjectives.
 // They are mutually exclusive.
 //===----------------------------------------------------------------------===//
 
 class ISA_MIPS2    { list<Predicate> InsnPredicates = [HasMips2]; }
 class ISA_MIPS3    { list<Predicate> InsnPredicates = [HasMips3]; }
+class ISA_MIPS32   { list<Predicate> InsnPredicates = [HasMips32]; }
 class ISA_MIPS32R2 { list<Predicate> InsnPredicates = [HasMips32r2]; }
+class ISA_MIPS64   { list<Predicate> InsnPredicates = [HasMips64]; }
 class ISA_MIPS64R2 { list<Predicate> InsnPredicates = [HasMips64r2]; }
 
 // The portions of MIPS-III that were also added to MIPS32
 class INSN_MIPS3_32 { list<Predicate> InsnPredicates = [HasMips3_32]; }
 
 // The portions of MIPS-IV that were also added to MIPS32
 class INSN_MIPS4_32 { list<Predicate> InsnPredicates = [HasMips4_32]; }
 
InstSE<(outs RO:$rt), (ins mem_ea:$addr), !strconcat(opstr, "\t$rt, $addr"),
          !strconcat(opstr, "_lea")> {
   let isCodeGenOnly = 1;
   let DecoderMethod = "DecodeMem";
 }
 
 // Count Leading Ones/Zeros in Word
 class CountLeading0<string opstr, RegisterOperand RO>:
   InstSE<(outs RO:$rd), (ins RO:$rs), !strconcat(opstr, "\t$rd, $rs"),
-         [(set RO:$rd, (ctlz RO:$rs))], II_CLZ, FrmR, opstr>,
-  AdditionalRequires<[HasBitCount]>;
+         [(set RO:$rd, (ctlz RO:$rs))], II_CLZ, FrmR, opstr>;
 
 class CountLeading1<string opstr, RegisterOperand RO>:
   InstSE<(outs RO:$rd), (ins RO:$rs), !strconcat(opstr, "\t$rd, $rs"),
-         [(set RO:$rd, (ctlz (not RO:$rs)))], II_CLO, FrmR, opstr>,
-  AdditionalRequires<[HasBitCount]>;
+         [(set RO:$rd, (ctlz (not RO:$rs)))], II_CLO, FrmR, opstr>;
 
 // Sign Extend in Register.
 class SignExtInReg<string opstr, ValueType vt, RegisterOperand RO,
                    InstrItinClass itin> :
   InstSE<(outs RO:$rd), (ins RO:$rt), !strconcat(opstr, "\t$rd, $rt"),
          [(set RO:$rd, (sext_inreg RO:$rt, vt))], itin, FrmR, opstr>;
 
 // Subword Swap

 
 /// Sign Ext In Register Instructions.
 def SEB : MMRel, SignExtInReg<"seb", i8, GPR32Opnd, II_SEB>,
           SEB_FM<0x10, 0x20>, ISA_MIPS32R2;
 def SEH : MMRel, SignExtInReg<"seh", i16, GPR32Opnd, II_SEH>,
           SEB_FM<0x18, 0x20>, ISA_MIPS32R2;
 
 /// Count Leading
-def CLZ : MMRel, CountLeading0<"clz", GPR32Opnd>, CLO_FM<0x20>;
-def CLO : MMRel, CountLeading1<"clo", GPR32Opnd>, CLO_FM<0x21>;
+def CLZ : MMRel, CountLeading0<"clz", GPR32Opnd>, CLO_FM<0x20>, ISA_MIPS32;
+def CLO : MMRel, CountLeading1<"clo", GPR32Opnd>, CLO_FM<0x21>, ISA_MIPS32;
 
 /// Word Swap Bytes Within Halfwords
 def WSBH : MMRel, SubwordSwap<"wsbh", GPR32Opnd>, SEB_FM<2, 0x20>, ISA_MIPS32R2;
 
 /// No operation.
 def NOP : PseudoSE<(outs), (ins), []>, PseudoInstExpansion<(SLL ZERO, ZERO, 0)>;
 
 // FrameIndexes are legalized when they are operands from load/store

lib/Target/Mips/MipsSubtarget.h

protected:
   bool HasMips3_32;
 
   // HasMips4_32 - Has the subset of MIPS-IV present in MIPS32
   bool HasMips4_32;
 
   // HasMips4_32r2 - Has the subset of MIPS-IV present in MIPS32r2
   bool HasMips4_32r2;
 
-  // HasBitCount - Count leading '1' and '0' bits.
-  bool HasBitCount;
-
   // InMips16 -- can process Mips16 instructions
   bool InMips16Mode;
 
   // Mips16 hard float
   bool InMips16HardFloat;
 
   // PreviousInMips16 -- the function we just processed was in Mips 16 Mode
   bool PreviousInMips16Mode;
public:
 
   bool mipsSEUsesSoftFloat() const;
 
   bool enableLongBranchPass() const {
     return hasStandardEncoding() || allowMixed16_32();
   }
 
   /// Features related to the presence of specific instructions.
-  bool hasBitCount()  const { return HasBitCount; }
   bool hasExtractInsert() const { return !inMips16Mode() && hasMips32r2(); }
 
   const InstrItineraryData &getInstrItineraryData() const { return InstrItins; }
   bool allowMixed16_32() const { return inMips16ModeDefault() |
                                         AllowMixed16_32;}
 
   bool os16() const { return Os16;};
 

lib/Target/Mips/MipsSubtarget.cpp

 
 MipsSubtarget::MipsSubtarget(const std::string &TT, const std::string &CPU,
                              const std::string &FS, bool little,
                              Reloc::Model _RM, MipsTargetMachine *_TM)
     : MipsGenSubtargetInfo(TT, CPU, FS), MipsArchVersion(Mips32),
       MipsABI(UnknownABI), IsLittle(little), IsSingleFloat(false),
       IsFP64bit(false), IsNaN2008bit(false), IsGP64bit(false), HasVFPU(false),
       HasCnMips(false), IsLinux(true), HasMips3_32(false), HasMips4_32(false),
-      HasMips4_32r2(false), HasBitCount(false), InMips16Mode(false),
+      HasMips4_32r2(false), InMips16Mode(false),
       InMips16HardFloat(Mips16HardFloat), InMicroMipsMode(false), HasDSP(false),
       HasDSPR2(false), AllowMixed16_32(Mixed16_32 | Mips_Os16), Os16(Mips_Os16),
       HasMSA(false), RM(_RM), OverrideMode(NoOverride), TM(_TM),
       TargetTriple(TT) {
   std::string CPUName = CPU;
   CPUName = selectMipsCPU(TT, CPUName);
 
   // Parse features string.
MipsSubtarget::MipsSubtarget(const std::string &TT, const std::string &CPU,
   // Is the target system Linux ?
   if (TT.find("linux") == std::string::npos)
     IsLinux = false;
 
   // Set UseSmallSection.
   // TODO: Investigate the IsLinux check. I suspect it's really checking for
   //       bare-metal.
   UseSmallSection = !IsLinux && (RM == Reloc::Static);
-  // set some subtarget specific features
-  if (inMips16Mode())
-    HasBitCount=false;
 }
 
 bool
 MipsSubtarget::enablePostRAScheduler(CodeGenOpt::Level OptLevel,
                                     TargetSubtargetInfo::AntiDepBreakMode &Mode,
                                      RegClassVector &CriticalPathRCs) const {
   Mode = TargetSubtargetInfo::ANTIDEP_NONE;
   CriticalPathRCs.clear();

test/MC/Mips/mips32/invalid-mips64.s

+# Instructions that are invalid
+#
+# RUN: not llvm-mc %s -triple=mips64-unknown-linux -show-encoding -mcpu=mips32 \
+# RUN:     2>%t1
+# RUN: FileCheck %s < %t1
+
+  .set noat
+  dclo  $s2,$a2    # CHECK: :[[@LINE]]:{{[0-9]+}}: error: instruction requires a CPU feature not currently enabled
+  dclz  $s0,$t9    # CHECK: :[[@LINE]]:{{[0-9]+}}: error: instruction requires a CPU feature not currently enabled