| //===-- NVPTXAsmPrinter.h - NVPTX LLVM assembly writer ----------*- C++ -*-===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file contains a printer that converts from our internal representation |
| // of machine-dependent LLVM code to NVPTX assembly language. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_LIB_TARGET_NVPTX_NVPTXASMPRINTER_H |
| #define LLVM_LIB_TARGET_NVPTX_NVPTXASMPRINTER_H |
| |
| #include "NVPTX.h" |
| #include "NVPTXSubtarget.h" |
| #include "NVPTXTargetMachine.h" |
| #include "llvm/ADT/DenseMap.h" |
| #include "llvm/ADT/SmallVector.h" |
| #include "llvm/ADT/StringRef.h" |
| #include "llvm/CodeGen/AsmPrinter.h" |
| #include "llvm/CodeGen/MachineFunction.h" |
| #include "llvm/CodeGen/MachineLoopInfo.h" |
| #include "llvm/IR/Constants.h" |
| #include "llvm/IR/DebugLoc.h" |
| #include "llvm/IR/DerivedTypes.h" |
| #include "llvm/IR/Function.h" |
| #include "llvm/IR/GlobalValue.h" |
| #include "llvm/IR/Value.h" |
| #include "llvm/MC/MCExpr.h" |
| #include "llvm/MC/MCStreamer.h" |
| #include "llvm/MC/MCSymbol.h" |
| #include "llvm/Pass.h" |
| #include "llvm/Support/Casting.h" |
| #include "llvm/Support/Compiler.h" |
| #include "llvm/Support/ErrorHandling.h" |
| #include "llvm/Support/raw_ostream.h" |
| #include "llvm/Target/TargetMachine.h" |
| #include <algorithm> |
| #include <cassert> |
| #include <map> |
| #include <memory> |
| #include <string> |
| #include <vector> |
| |
| // 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). |
| |
| namespace llvm { |
| |
| class MCOperand; |
| |
| 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 numSymbols; // number of symbol addresses |
| |
| private: |
| const unsigned size; // size of the buffer in bytes |
| std::vector<unsigned char> buffer; // the buffer |
| SmallVector<unsigned, 4> symbolPosInBuffer; |
| SmallVector<const Value *, 4> Symbols; |
| // SymbolsBeforeStripping[i] is the original form of Symbols[i] before |
| // stripping pointer casts, i.e., |
| // Symbols[i] == SymbolsBeforeStripping[i]->stripPointerCasts(). |
| // |
| // We need to keep these values because AggBuffer::print decides whether to |
| // emit a "generic()" cast for Symbols[i] depending on the address space of |
| // SymbolsBeforeStripping[i]. |
| SmallVector<const Value *, 4> SymbolsBeforeStripping; |
| unsigned curpos; |
| raw_ostream &O; |
| NVPTXAsmPrinter &AP; |
| bool EmitGeneric; |
| |
| public: |
| AggBuffer(unsigned size, raw_ostream &O, NVPTXAsmPrinter &AP) |
| : size(size), buffer(size), O(O), AP(AP) { |
| curpos = 0; |
| numSymbols = 0; |
| EmitGeneric = AP.EmitGeneric; |
| } |
| |
| // Copy Num bytes from Ptr. |
| // if Bytes > Num, zero fill up to Bytes. |
| 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(const Value *GVar, const Value *GVarBeforeStripping) { |
| symbolPosInBuffer.push_back(curpos); |
| Symbols.push_back(GVar); |
| SymbolsBeforeStripping.push_back(GVarBeforeStripping); |
| 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 (static_cast<const NVPTXTargetMachine &>(AP.TM).is64Bit()) |
| nBytes = 8; |
| for (pos = 0; pos < size; pos += nBytes) { |
| if (pos) |
| O << ", "; |
| if (pos == nextSymbolPos) { |
| const Value *v = Symbols[nSym]; |
| const Value *v0 = SymbolsBeforeStripping[nSym]; |
| if (const GlobalValue *GVar = dyn_cast<GlobalValue>(v)) { |
| MCSymbol *Name = AP.getSymbol(GVar); |
| PointerType *PTy = dyn_cast<PointerType>(v0->getType()); |
| bool IsNonGenericPointer = false; // Is v0 a non-generic pointer? |
| if (PTy && PTy->getAddressSpace() != 0) { |
| IsNonGenericPointer = true; |
| } |
| if (EmitGeneric && !isa<Function>(v) && !IsNonGenericPointer) { |
| O << "generic("; |
| Name->print(O, AP.MAI); |
| O << ")"; |
| } else { |
| Name->print(O, AP.MAI); |
| } |
| } else if (const ConstantExpr *CExpr = dyn_cast<ConstantExpr>(v0)) { |
| const MCExpr *Expr = |
| AP.lowerConstantForGV(cast<Constant>(CExpr), false); |
| AP.printMCExpr(*Expr, O); |
| } else |
| llvm_unreachable("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; |
| |
| private: |
| StringRef getPassName() const override { return "NVPTX Assembly Printer"; } |
| |
| const Function *F; |
| std::string CurrentFnName; |
| |
| void emitStartOfAsmFile(Module &M) override; |
| void emitBasicBlockStart(const MachineBasicBlock &MBB) override; |
| void emitFunctionEntryLabel() override; |
| void emitFunctionBodyStart() override; |
| void emitFunctionBodyEnd() override; |
| void emitImplicitDef(const MachineInstr *MI) const override; |
| |
| void emitInstruction(const MachineInstr *) override; |
| void lowerToMCInst(const MachineInstr *MI, MCInst &OutMI); |
| bool lowerOperand(const MachineOperand &MO, MCOperand &MCOp); |
| MCOperand GetSymbolRef(const MCSymbol *Symbol); |
| unsigned encodeVirtualRegister(unsigned Reg); |
| |
| void printMemOperand(const MachineInstr *MI, int opNum, raw_ostream &O, |
| const char *Modifier = nullptr); |
| void printModuleLevelGV(const GlobalVariable *GVar, raw_ostream &O, |
| bool = false); |
| void printParamName(Function::const_arg_iterator I, int paramIndex, |
| raw_ostream &O); |
| void emitGlobals(const Module &M); |
| void emitHeader(Module &M, raw_ostream &O, const NVPTXSubtarget &STI); |
| void emitKernelFunctionDirectives(const Function &F, raw_ostream &O) const; |
| void emitVirtualRegister(unsigned int vr, raw_ostream &); |
| void emitFunctionParamList(const Function *, raw_ostream &O); |
| void emitFunctionParamList(const MachineFunction &MF, raw_ostream &O); |
| void setAndEmitFunctionVirtualRegisters(const MachineFunction &MF); |
| void printReturnValStr(const Function *, raw_ostream &O); |
| void printReturnValStr(const MachineFunction &MF, raw_ostream &O); |
| bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo, |
| const char *ExtraCode, raw_ostream &) override; |
| void printOperand(const MachineInstr *MI, int opNum, raw_ostream &O); |
| bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo, |
| const char *ExtraCode, raw_ostream &) override; |
| |
| const MCExpr *lowerConstantForGV(const Constant *CV, bool ProcessingGeneric); |
| void printMCExpr(const MCExpr &Expr, raw_ostream &OS); |
| |
| protected: |
| bool doInitialization(Module &M) override; |
| bool doFinalization(Module &M) override; |
| |
| private: |
| bool GlobalsEmitted; |
| |
| // This is specific per MachineFunction. |
| const MachineRegisterInfo *MRI; |
| // The contents are specific for each |
| // MachineFunction. But the size of the |
| // array is not. |
| typedef DenseMap<unsigned, unsigned> VRegMap; |
| typedef DenseMap<const TargetRegisterClass *, VRegMap> VRegRCMap; |
| VRegRCMap VRegMapping; |
| |
| // List of variables demoted to a function scope. |
| std::map<const Function *, std::vector<const GlobalVariable *>> localDecls; |
| |
| void emitPTXGlobalVariable(const GlobalVariable *GVar, raw_ostream &O); |
| void emitPTXAddressSpace(unsigned int AddressSpace, raw_ostream &O) const; |
| std::string getPTXFundamentalTypeStr(Type *Ty, bool = true) const; |
| void printScalarConstant(const Constant *CPV, raw_ostream &O); |
| void printFPConstant(const ConstantFP *Fp, raw_ostream &O); |
| void bufferLEByte(const Constant *CPV, int Bytes, AggBuffer *aggBuffer); |
| void bufferAggregateConstant(const Constant *CV, AggBuffer *aggBuffer); |
| |
| void emitLinkageDirective(const GlobalValue *V, raw_ostream &O); |
| void emitDeclarations(const Module &, raw_ostream &O); |
| void emitDeclaration(const Function *, raw_ostream &O); |
| void emitDemotedVars(const Function *, raw_ostream &); |
| |
| bool lowerImageHandleOperand(const MachineInstr *MI, unsigned OpNo, |
| MCOperand &MCOp); |
| void lowerImageHandleSymbol(unsigned Index, MCOperand &MCOp); |
| |
| bool isLoopHeaderOfNoUnroll(const MachineBasicBlock &MBB) const; |
| |
| // Used to control the need to emit .generic() in the initializer of |
| // module scope variables. |
| // Although ptx supports the hybrid mode like the following, |
| // .global .u32 a; |
| // .global .u32 b; |
| // .global .u32 addr[] = {a, generic(b)} |
| // we have difficulty representing the difference in the NVVM IR. |
| // |
| // Since the address value should always be generic in CUDA C and always |
| // be specific in OpenCL, we use this simple control here. |
| // |
| bool EmitGeneric; |
| |
| public: |
| NVPTXAsmPrinter(TargetMachine &TM, std::unique_ptr<MCStreamer> Streamer) |
| : AsmPrinter(TM, std::move(Streamer)), |
| EmitGeneric(static_cast<NVPTXTargetMachine &>(TM).getDrvInterface() == |
| NVPTX::CUDA) {} |
| |
| bool runOnMachineFunction(MachineFunction &F) override; |
| |
| void getAnalysisUsage(AnalysisUsage &AU) const override { |
| AU.addRequired<MachineLoopInfo>(); |
| AsmPrinter::getAnalysisUsage(AU); |
| } |
| |
| std::string getVirtualRegisterName(unsigned) const; |
| |
| const MCSymbol *getFunctionFrameSymbol() const override; |
| |
| // Make emitGlobalVariable() no-op for NVPTX. |
| // Global variables have been already emitted by the time the base AsmPrinter |
| // attempts to do so in doFinalization() (see NVPTXAsmPrinter::emitGlobals()). |
| void emitGlobalVariable(const GlobalVariable *GV) override {} |
| }; |
| |
| } // end namespace llvm |
| |
| #endif // LLVM_LIB_TARGET_NVPTX_NVPTXASMPRINTER_H |