This patch adds a new NVPTX back-end to LLVM which supports code generation for NVIDIA PTX 3.0. This back-end will (eventually) replace the current PTX back-end, while maintaining compatibility with it.

The new target machines are:

nvptx (old ptx32) => 32-bit PTX
nvptx64 (old ptx64) => 64-bit PTX

The sources are based on the internal NVIDIA NVPTX back-end, and
contain more functionality than the current PTX back-end currently
provides.

NV_CONTRIB

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156196 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 318 insertions, 0 deletions

diff --git a/lib/Target/NVPTX/NVPTXAsmPrinter.h b/lib/Target/NVPTX/NVPTXAsmPrinter.h
new file mode 100644
index 0000000000..a035299450
--- /dev/null
+++ b/lib/Target/NVPTX/NVPTXAsmPrinter.h
@@ -0,0 +1,318 @@
+//===-- NVPTXAsmPrinter.h - NVPTX LLVM assembly writer --------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains a printer that converts from our internal representation
+// of machine-dependent LLVM code to NVPTX assembly language.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef NVPTXASMPRINTER_H
+#define NVPTXASMPRINTER_H
+
+#include "NVPTX.h"
+#include "NVPTXTargetMachine.h"
+#include "NVPTXSubtarget.h"
+#include "llvm/Function.h"
+#include "llvm/CodeGen/AsmPrinter.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCExpr.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/MC/MCSymbol.h"
+#include "llvm/Support/FormattedStream.h"
+#include "llvm/Target/Mangler.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/StringExtras.h"
+#include <fstream>
+
+// The ptx syntax and format is very different from that usually seem in a .s
+// file,
+// therefore we are not able to use the MCAsmStreamer interface here.
+//
+// We are handcrafting the output method here.
+//
+// A better approach is to clone the MCAsmStreamer to a MCPTXAsmStreamer
+// (subclass of MCStreamer).
+
+// This is defined in AsmPrinter.cpp.
+// Used to process the constant expressions in initializers.
+namespace nvptx {
+const llvm::MCExpr *LowerConstant(const llvm::Constant *CV,
+                                  llvm::AsmPrinter &AP) ;
+}
+
+namespace llvm {
+
+class LineReader {
+private:
+  unsigned theCurLine ;
+  std::ifstream fstr;
+  char buff[512];
+  std::string theFileName;
+  SmallVector<unsigned, 32> lineOffset;
+public:
+  LineReader(std::string filename) {
+    theCurLine = 0;
+    fstr.open(filename.c_str());
+    theFileName = filename;
+  }
+  std::string fileName() { return theFileName; }
+  ~LineReader() {
+    fstr.close();
+  }
+  std::string readLine(unsigned line);
+};
+
+
+
+class LLVM_LIBRARY_VISIBILITY NVPTXAsmPrinter : public AsmPrinter {
+
+
+  class AggBuffer {
+    // Used to buffer the emitted string for initializing global
+    // aggregates.
+    //
+    // Normally an aggregate (array, vector or structure) is emitted
+    // as a u8[]. However, if one element/field of the aggregate
+    // is a non-NULL address, then the aggregate is emitted as u32[]
+    // or u64[].
+    //
+    // We first layout the aggregate in 'buffer' in bytes, except for
+    // those symbol addresses. For the i-th symbol address in the
+    //aggregate, its corresponding 4-byte or 8-byte elements in 'buffer'
+    // are filled with 0s. symbolPosInBuffer[i-1] records its position
+    // in 'buffer', and Symbols[i-1] records the Value*.
+    //
+    // Once we have this AggBuffer setup, we can choose how to print
+    // it out.
+  public:
+    unsigned size;   // size of the buffer in bytes
+    unsigned char *buffer; // the buffer
+    unsigned numSymbols;   // number of symbol addresses
+    SmallVector<unsigned, 4> symbolPosInBuffer;
+    SmallVector<Value *, 4> Symbols;
+
+  private:
+    unsigned curpos;
+    raw_ostream &O;
+    NVPTXAsmPrinter &AP;
+
+  public:
+    AggBuffer(unsigned _size, raw_ostream &_O, NVPTXAsmPrinter &_AP)
+    :O(_O),AP(_AP) {
+      buffer = new unsigned char[_size];
+      size = _size;
+      curpos = 0;
+      numSymbols = 0;
+    }
+    ~AggBuffer() {
+      delete [] buffer;
+    }
+    unsigned addBytes(unsigned char *Ptr, int Num, int Bytes) {
+      assert((curpos+Num) <= size);
+      assert((curpos+Bytes) <= size);
+      for ( int i= 0; i < Num; ++i) {
+        buffer[curpos] = Ptr[i];
+        curpos ++;
+      }
+      for ( int i=Num; i < Bytes ; ++i) {
+        buffer[curpos] = 0;
+        curpos ++;
+      }
+      return curpos;
+    }
+    unsigned addZeros(int Num) {
+      assert((curpos+Num) <= size);
+      for ( int i= 0; i < Num; ++i) {
+        buffer[curpos] = 0;
+        curpos ++;
+      }
+      return curpos;
+    }
+    void addSymbol(Value *GVar) {
+      symbolPosInBuffer.push_back(curpos);
+      Symbols.push_back(GVar);
+      numSymbols++;
+    }
+    void print() {
+      if (numSymbols == 0) {
+        // print out in bytes
+        for (unsigned i=0; i<size; i++) {
+          if (i)
+            O << ", ";
+          O << (unsigned int)buffer[i];
+        }
+      }
+      else {
+        // print out in 4-bytes or 8-bytes
+        unsigned int pos = 0;
+        unsigned int nSym = 0;
+        unsigned int nextSymbolPos = symbolPosInBuffer[nSym];
+        unsigned int nBytes = 4;
+        if (AP.nvptxSubtarget.is64Bit())
+          nBytes = 8;
+        for (pos=0; pos<size; pos+=nBytes) {
+          if (pos)
+            O << ", ";
+          if (pos == nextSymbolPos) {
+            Value *v = Symbols[nSym];
+            if (GlobalValue *GVar = dyn_cast<GlobalValue>(v)) {
+              MCSymbol *Name = AP.Mang->getSymbol(GVar);
+              O << *Name;
+            }
+            else if (ConstantExpr *Cexpr =
+                dyn_cast<ConstantExpr>(v)) {
+              O << *nvptx::LowerConstant(Cexpr, AP);
+            }
+            else
+              assert(0 && "symbol type unknown");
+            nSym++;
+            if (nSym >= numSymbols)
+              nextSymbolPos = size+1;
+            else
+              nextSymbolPos = symbolPosInBuffer[nSym];
+          }
+          else
+            if (nBytes == 4)
+              O << *(unsigned int*)(buffer+pos);
+            else
+              O << *(unsigned long long*)(buffer+pos);
+        }
+      }
+    }
+  };
+
+  friend class AggBuffer;
+
+  virtual void emitSrcInText(StringRef filename, unsigned line);
+
+private :
+  virtual const char *getPassName() const {
+    return "NVPTX Assembly Printer";
+  }
+
+  const Function *F;
+  std::string CurrentFnName;
+
+  void EmitFunctionEntryLabel();
+  void EmitFunctionBodyStart();
+  void EmitFunctionBodyEnd();
+
+  void EmitInstruction(const MachineInstr *);
+
+  void EmitAlignment(unsigned NumBits, const GlobalValue *GV = 0) const {}
+
+  void printGlobalVariable(const GlobalVariable *GVar);
+  void printOperand(const MachineInstr *MI, int opNum, raw_ostream &O,
+                    const char *Modifier=0);
+  void printLdStCode(const MachineInstr *MI, int opNum, raw_ostream &O,
+                     const char *Modifier=0);
+  void printVecModifiedImmediate(const MachineOperand &MO,
+                                 const char *Modifier, raw_ostream &O);
+  void printMemOperand(const MachineInstr *MI, int opNum, raw_ostream &O,
+                       const char *Modifier=0);
+  void printImplicitDef(const MachineInstr *MI, raw_ostream &O) const;
+  // definition autogenerated.
+  void printInstruction(const MachineInstr *MI, raw_ostream &O);
+  void printModuleLevelGV(GlobalVariable* GVar, raw_ostream &O,
+                          bool=false);
+  void printParamName(int paramIndex, raw_ostream &O);
+  void printParamName(Function::const_arg_iterator I, int paramIndex,
+                      raw_ostream &O);
+  void emitHeader(Module &M, raw_ostream &O);
+  void emitKernelFunctionDirectives(const Function& F,
+                                    raw_ostream &O) const;
+  void emitVirtualRegister(unsigned int vr, bool isVec, raw_ostream &O);
+  void emitFunctionExternParamList(const MachineFunction &MF);
+  void emitFunctionParamList(const Function *, raw_ostream &O);
+  void emitFunctionParamList(const MachineFunction &MF, raw_ostream &O);
+  void setAndEmitFunctionVirtualRegisters(const MachineFunction &MF);
+  void emitFunctionTempData(const MachineFunction &MF,
+                            unsigned &FrameSize);
+  bool isImageType(const Type *Ty);
+  bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
+                       unsigned AsmVariant, const char *ExtraCode,
+                       raw_ostream &);
+  bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
+                             unsigned AsmVariant, const char *ExtraCode,
+                             raw_ostream &);
+  void printReturnValStr(const Function *, raw_ostream &O);
+  void printReturnValStr(const MachineFunction &MF, raw_ostream &O);
+
+protected:
+  bool doInitialization(Module &M);
+  bool doFinalization(Module &M);
+
+private:
+  std::string CurrentBankselLabelInBasicBlock;
+
+  // This is specific per MachineFunction.
+  const MachineRegisterInfo *MRI;
+  // The contents are specific for each
+  // MachineFunction. But the size of the
+  // array is not.
+  std::map<unsigned, unsigned> *VRidGlobal2LocalMap;
+  // cache the subtarget here.
+  const NVPTXSubtarget &nvptxSubtarget;
+  // Build the map between type name and ID based on module's type
+  // symbol table.
+  std::map<const Type *, std::string> TypeNameMap;
+
+  // List of variables demoted to a function scope.
+  std::map<const Function *, std::vector<GlobalVariable *> > localDecls;
+
+  // To record filename to ID mapping
+  std::map<std::string, unsigned> filenameMap;
+  void recordAndEmitFilenames(Module &);
+
+  void emitPTXGlobalVariable(const GlobalVariable *GVar, raw_ostream &O);
+  void emitPTXAddressSpace(unsigned int AddressSpace,
+                           raw_ostream &O) const;
+  std::string getPTXFundamentalTypeStr(const Type *Ty, bool=true) const ;
+  void printScalarConstant(Constant *CPV, raw_ostream &O) ;
+  void printFPConstant(const ConstantFP *Fp, raw_ostream &O) ;
+  void bufferLEByte(Constant *CPV, int Bytes, AggBuffer *aggBuffer) ;
+  void bufferAggregateConstant(Constant *CV, AggBuffer *aggBuffer) ;
+
+  void printOperandProper(const MachineOperand &MO);
+
+  void emitLinkageDirective(const GlobalValue* V, raw_ostream &O);
+  void emitDeclarations(Module &, raw_ostream &O);
+  void emitDeclaration(const Function *, raw_ostream &O);
+
+  static const char *getRegisterName(unsigned RegNo);
+  void emitDemotedVars(const Function *, raw_ostream &);
+
+  LineReader *reader;
+  LineReader *getReader(std::string);
+public:
+  NVPTXAsmPrinter(TargetMachine &TM,
+                  MCStreamer &Streamer)
+  : AsmPrinter(TM, Streamer),
+    nvptxSubtarget(TM.getSubtarget<NVPTXSubtarget>()) {
+    CurrentBankselLabelInBasicBlock = "";
+    VRidGlobal2LocalMap = NULL;
+    reader = NULL;
+  }
+
+  ~NVPTXAsmPrinter() {
+    if (!reader)
+      delete reader;
+  }
+
+  bool ignoreLoc(const MachineInstr &);
+
+  virtual void getVirtualRegisterName(unsigned, bool, raw_ostream &);
+
+  DebugLoc prevDebugLoc;
+  void emitLineNumberAsDotLoc(const MachineInstr &);
+};
+} // end of namespace
+
+#endif