src/llvm/lib/Target/NVPTX/NVPTXAsmPrinter.h

   1 //===-- NVPTXAsmPrinter.h - NVPTX LLVM assembly writer --------------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file contains a printer that converts from our internal representation
  11 // of machine-dependent LLVM code to NVPTX assembly language.
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #ifndef NVPTXASMPRINTER_H
  16 #define NVPTXASMPRINTER_H
  17
  18 #include "NVPTX.h"
  19 #include "NVPTXSubtarget.h"
  20 #include "NVPTXTargetMachine.h"
  21 #include "llvm/ADT/SmallString.h"
  22 #include "llvm/ADT/StringExtras.h"
  23 #include "llvm/CodeGen/AsmPrinter.h"
  24 #include "llvm/IR/Function.h"
  25 #include "llvm/MC/MCAsmInfo.h"
  26 #include "llvm/MC/MCExpr.h"
  27 #include "llvm/MC/MCSymbol.h"
  28 #include "llvm/Support/CommandLine.h"
  29 #include "llvm/Support/FormattedStream.h"
  30 #include "llvm/Target/Mangler.h"
  31 #include "llvm/Target/TargetMachine.h"
  32 #include <fstream>
  33
  34 // The ptx syntax and format is very different from that usually seem in a .s
  35 // file,
  36 // therefore we are not able to use the MCAsmStreamer interface here.
  37 //
  38 // We are handcrafting the output method here.
  39 //
  40 // A better approach is to clone the MCAsmStreamer to a MCPTXAsmStreamer
  41 // (subclass of MCStreamer).
  42
  43 // This is defined in AsmPrinter.cpp.
  44 // Used to process the constant expressions in initializers.
  45 namespace nvptx {
  46 const llvm::MCExpr *LowerConstant(const llvm::Constant *CV,
  47                                   llvm::AsmPrinter &AP) ;
  48 }
  49
  50 namespace llvm {
  51
  52 class LineReader {
  53 private:
  54   unsigned theCurLine ;
  55   std::ifstream fstr;
  56   char buff[512];
  57   std::string theFileName;
  58   SmallVector<unsigned, 32> lineOffset;
  59 public:
  60   LineReader(std::string filename) {
  61     theCurLine = 0;
  62     fstr.open(filename.c_str());
  63     theFileName = filename;
  64   }
  65   std::string fileName() { return theFileName; }
  66   ~LineReader() {
  67     fstr.close();
  68   }
  69   std::string readLine(unsigned line);
  70 };
  71
  72
  73
  74 class LLVM_LIBRARY_VISIBILITY NVPTXAsmPrinter : public AsmPrinter {
  75
  76
  77   class AggBuffer {
  78     // Used to buffer the emitted string for initializing global
  79     // aggregates.
  80     //
  81     // Normally an aggregate (array, vector or structure) is emitted
  82     // as a u8[]. However, if one element/field of the aggregate
  83     // is a non-NULL address, then the aggregate is emitted as u32[]
  84     // or u64[].
  85     //
  86     // We first layout the aggregate in 'buffer' in bytes, except for
  87     // those symbol addresses. For the i-th symbol address in the
  88     //aggregate, its corresponding 4-byte or 8-byte elements in 'buffer'
  89     // are filled with 0s. symbolPosInBuffer[i-1] records its position
  90     // in 'buffer', and Symbols[i-1] records the Value*.
  91     //
  92     // Once we have this AggBuffer setup, we can choose how to print
  93     // it out.
  94   public:
  95     unsigned size;   // size of the buffer in bytes
  96     unsigned char *buffer; // the buffer
  97     unsigned numSymbols;   // number of symbol addresses
  98     SmallVector<unsigned, 4> symbolPosInBuffer;
  99     SmallVector<Value *, 4> Symbols;
 100
 101   private:
 102     unsigned curpos;
 103     raw_ostream &O;
 104     NVPTXAsmPrinter &AP;
 105
 106   public:
 107     AggBuffer(unsigned _size, raw_ostream &_O, NVPTXAsmPrinter &_AP)
 108     :O(_O),AP(_AP) {
 109       buffer = new unsigned char[_size];
 110       size = _size;
 111       curpos = 0;
 112       numSymbols = 0;
 113     }
 114     ~AggBuffer() {
 115       delete [] buffer;
 116     }
 117     unsigned addBytes(unsigned char *Ptr, int Num, int Bytes) {
 118       assert((curpos+Num) <= size);
 119       assert((curpos+Bytes) <= size);
 120       for ( int i= 0; i < Num; ++i) {
 121         buffer[curpos] = Ptr[i];
 122         curpos ++;
 123       }
 124       for ( int i=Num; i < Bytes ; ++i) {
 125         buffer[curpos] = 0;
 126         curpos ++;
 127       }
 128       return curpos;
 129     }
 130     unsigned addZeros(int Num) {
 131       assert((curpos+Num) <= size);
 132       for ( int i= 0; i < Num; ++i) {
 133         buffer[curpos] = 0;
 134         curpos ++;
 135       }
 136       return curpos;
 137     }
 138     void addSymbol(Value *GVar) {
 139       symbolPosInBuffer.push_back(curpos);
 140       Symbols.push_back(GVar);
 141       numSymbols++;
 142     }
 143     void print() {
 144       if (numSymbols == 0) {
 145         // print out in bytes
 146         for (unsigned i=0; i<size; i++) {
 147           if (i)
 148             O << ", ";
 149           O << (unsigned int)buffer[i];
 150         }
 151       } else {
 152         // print out in 4-bytes or 8-bytes
 153         unsigned int pos = 0;
 154         unsigned int nSym = 0;
 155         unsigned int nextSymbolPos = symbolPosInBuffer[nSym];
 156         unsigned int nBytes = 4;
 157         if (AP.nvptxSubtarget.is64Bit())
 158           nBytes = 8;
 159         for (pos=0; pos<size; pos+=nBytes) {
 160           if (pos)
 161             O << ", ";
 162           if (pos == nextSymbolPos) {
 163             Value *v = Symbols[nSym];
 164             if (GlobalValue *GVar = dyn_cast<GlobalValue>(v)) {
 165               MCSymbol *Name = AP.Mang->getSymbol(GVar);
 166               O << *Name;
 167             }
 168             else if (ConstantExpr *Cexpr =
 169                 dyn_cast<ConstantExpr>(v)) {
 170               O << *nvptx::LowerConstant(Cexpr, AP);
 171             } else
 172               llvm_unreachable("symbol type unknown");
 173             nSym++;
 174             if (nSym >= numSymbols)
 175               nextSymbolPos = size+1;
 176             else
 177               nextSymbolPos = symbolPosInBuffer[nSym];
 178           } else
 179             if (nBytes == 4)
 180               O << *(unsigned int*)(buffer+pos);
 181             else
 182               O << *(unsigned long long*)(buffer+pos);
 183         }
 184       }
 185     }
 186   };
 187
 188   friend class AggBuffer;
 189
 190   virtual void emitSrcInText(StringRef filename, unsigned line);
 191
 192 private :
 193   virtual const char *getPassName() const {
 194     return "NVPTX Assembly Printer";
 195   }
 196
 197   const Function *F;
 198   std::string CurrentFnName;
 199
 200   void EmitFunctionEntryLabel();
 201   void EmitFunctionBodyStart();
 202   void EmitFunctionBodyEnd();
 203
 204   void EmitInstruction(const MachineInstr *);
 205
 206   void EmitAlignment(unsigned NumBits, const GlobalValue *GV = 0) const {}
 207
 208   void printGlobalVariable(const GlobalVariable *GVar);
 209   void printOperand(const MachineInstr *MI, int opNum, raw_ostream &O,
 210                     const char *Modifier=0);
 211   void printLdStCode(const MachineInstr *MI, int opNum, raw_ostream &O,
 212                      const char *Modifier=0);
 213   void printVecModifiedImmediate(const MachineOperand &MO,
 214                                  const char *Modifier, raw_ostream &O);
 215   void printMemOperand(const MachineInstr *MI, int opNum, raw_ostream &O,
 216                        const char *Modifier=0);
 217   void printImplicitDef(const MachineInstr *MI, raw_ostream &O) const;
 218   // definition autogenerated.
 219   void printInstruction(const MachineInstr *MI, raw_ostream &O);
 220   void printModuleLevelGV(GlobalVariable* GVar, raw_ostream &O,
 221                           bool=false);
 222   void printParamName(int paramIndex, raw_ostream &O);
 223   void printParamName(Function::const_arg_iterator I, int paramIndex,
 224                       raw_ostream &O);
 225   void emitHeader(Module &M, raw_ostream &O);
 226   void emitKernelFunctionDirectives(const Function& F,
 227                                     raw_ostream &O) const;
 228   void emitVirtualRegister(unsigned int vr, bool isVec, raw_ostream &O);
 229   void emitFunctionExternParamList(const MachineFunction &MF);
 230   void emitFunctionParamList(const Function *, raw_ostream &O);
 231   void emitFunctionParamList(const MachineFunction &MF, raw_ostream &O);
 232   void setAndEmitFunctionVirtualRegisters(const MachineFunction &MF);
 233   void emitFunctionTempData(const MachineFunction &MF,
 234                             unsigned &FrameSize);
 235   bool isImageType(const Type *Ty);
 236   bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
 237                        unsigned AsmVariant, const char *ExtraCode,
 238                        raw_ostream &);
 239   bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
 240                              unsigned AsmVariant, const char *ExtraCode,
 241                              raw_ostream &);
 242   void printReturnValStr(const Function *, raw_ostream &O);
 243   void printReturnValStr(const MachineFunction &MF, raw_ostream &O);
 244
 245 protected:
 246   bool doInitialization(Module &M);
 247   bool doFinalization(Module &M);
 248
 249 private:
 250   std::string CurrentBankselLabelInBasicBlock;
 251
 252   // This is specific per MachineFunction.
 253   const MachineRegisterInfo *MRI;
 254   // The contents are specific for each
 255   // MachineFunction. But the size of the
 256   // array is not.
 257   std::map<unsigned, unsigned> *VRidGlobal2LocalMap;
 258   // cache the subtarget here.
 259   const NVPTXSubtarget &nvptxSubtarget;
 260   // Build the map between type name and ID based on module's type
 261   // symbol table.
 262   std::map<const Type *, std::string> TypeNameMap;
 263
 264   // List of variables demoted to a function scope.
 265   std::map<const Function *, std::vector<GlobalVariable *> > localDecls;
 266
 267   // To record filename to ID mapping
 268   std::map<std::string, unsigned> filenameMap;
 269   void recordAndEmitFilenames(Module &);
 270
 271   void emitPTXGlobalVariable(const GlobalVariable *GVar, raw_ostream &O);
 272   void emitPTXAddressSpace(unsigned int AddressSpace,
 273                            raw_ostream &O) const;
 274   std::string getPTXFundamentalTypeStr(const Type *Ty, bool=true) const ;
 275   void printScalarConstant(Constant *CPV, raw_ostream &O) ;
 276   void printFPConstant(const ConstantFP *Fp, raw_ostream &O) ;
 277   void bufferLEByte(Constant *CPV, int Bytes, AggBuffer *aggBuffer) ;
 278   void bufferAggregateConstant(Constant *CV, AggBuffer *aggBuffer) ;
 279
 280   void printOperandProper(const MachineOperand &MO);
 281
 282   void emitLinkageDirective(const GlobalValue* V, raw_ostream &O);
 283   void emitDeclarations(Module &, raw_ostream &O);
 284   void emitDeclaration(const Function *, raw_ostream &O);
 285
 286   static const char *getRegisterName(unsigned RegNo);
 287   void emitDemotedVars(const Function *, raw_ostream &);
 288
 289   LineReader *reader;
 290   LineReader *getReader(std::string);
 291 public:
 292   NVPTXAsmPrinter(TargetMachine &TM,
 293                   MCStreamer &Streamer)
 294   : AsmPrinter(TM, Streamer),
 295     nvptxSubtarget(TM.getSubtarget<NVPTXSubtarget>()) {
 296     CurrentBankselLabelInBasicBlock = "";
 297     VRidGlobal2LocalMap = NULL;
 298     reader = NULL;
 299   }
 300
 301   ~NVPTXAsmPrinter() {
 302     if (!reader)
 303       delete reader;
 304   }
 305
 306   bool ignoreLoc(const MachineInstr &);
 307
 308   virtual void getVirtualRegisterName(unsigned, bool, raw_ostream &);
 309
 310   DebugLoc prevDebugLoc;
 311   void emitLineNumberAsDotLoc(const MachineInstr &);
 312 };
 313 } // end of namespace
 314
 315 #endif