1 files changed, 348 insertions, 0 deletions
diff --git a/llvm/lib/Target/SPIRV/SPIRVAsmPrinter.cpp b/llvm/lib/Target/SPIRV/SPIRVAsmPrinter.cpp
new file mode 100644
index 000000000000..0de232651377
--- /dev/null
+++ b/llvm/lib/Target/SPIRV/SPIRVAsmPrinter.cpp
@@ -0,0 +1,348 @@
+//===-- SPIRVAsmPrinter.cpp - SPIR-V 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 the SPIR-V assembly language.
+//
+//===----------------------------------------------------------------------===//
+
+#include "MCTargetDesc/SPIRVInstPrinter.h"
+#include "SPIRV.h"
+#include "SPIRVInstrInfo.h"
+#include "SPIRVMCInstLower.h"
+#include "SPIRVModuleAnalysis.h"
+#include "SPIRVSubtarget.h"
+#include "SPIRVTargetMachine.h"
+#include "SPIRVUtils.h"
+#include "TargetInfo/SPIRVTargetInfo.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/CodeGen/AsmPrinter.h"
+#include "llvm/CodeGen/MachineConstantPool.h"
+#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/CodeGen/MachineInstr.h"
+#include "llvm/CodeGen/MachineModuleInfo.h"
+#include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCInst.h"
+#include "llvm/MC/MCStreamer.h"
+#include "llvm/MC/MCSymbol.h"
+#include "llvm/MC/TargetRegistry.h"
+#include "llvm/Support/raw_ostream.h"
+
+using namespace llvm;
+
+#define DEBUG_TYPE "asm-printer"
+
+namespace {
+class SPIRVAsmPrinter : public AsmPrinter {
+public:
+  explicit SPIRVAsmPrinter(TargetMachine &TM,
+                           std::unique_ptr<MCStreamer> Streamer)
+      : AsmPrinter(TM, std::move(Streamer)), ST(nullptr), TII(nullptr) {}
+  bool ModuleSectionsEmitted;
+  const SPIRVSubtarget *ST;
+  const SPIRVInstrInfo *TII;
+
+  StringRef getPassName() const override { return "SPIRV Assembly Printer"; }
+  void printOperand(const MachineInstr *MI, int OpNum, raw_ostream &O);
+  bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
+                       const char *ExtraCode, raw_ostream &O) override;
+
+  void outputMCInst(MCInst &Inst);
+  void outputInstruction(const MachineInstr *MI);
+  void outputModuleSection(SPIRV::ModuleSectionType MSType);
+  void outputEntryPoints();
+  void outputDebugSourceAndStrings(const Module &M);
+  void outputOpMemoryModel();
+  void outputOpFunctionEnd();
+  void outputExtFuncDecls();
+  void outputModuleSections();
+
+  void emitInstruction(const MachineInstr *MI) override;
+  void emitFunctionEntryLabel() override {}
+  void emitFunctionHeader() override;
+  void emitFunctionBodyStart() override {}
+  void emitFunctionBodyEnd() override;
+  void emitBasicBlockStart(const MachineBasicBlock &MBB) override;
+  void emitBasicBlockEnd(const MachineBasicBlock &MBB) override {}
+  void emitGlobalVariable(const GlobalVariable *GV) override {}
+  void emitOpLabel(const MachineBasicBlock &MBB);
+  void emitEndOfAsmFile(Module &M) override;
+  bool doInitialization(Module &M) override;
+
+  void getAnalysisUsage(AnalysisUsage &AU) const override;
+  SPIRV::ModuleAnalysisInfo *MAI;
+};
+} // namespace
+
+void SPIRVAsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
+  AU.addRequired<SPIRVModuleAnalysis>();
+  AU.addPreserved<SPIRVModuleAnalysis>();
+  AsmPrinter::getAnalysisUsage(AU);
+}
+
+// If the module has no functions, we need output global info anyway.
+void SPIRVAsmPrinter::emitEndOfAsmFile(Module &M) {
+  if (ModuleSectionsEmitted == false) {
+    outputModuleSections();
+    ModuleSectionsEmitted = true;
+  }
+}
+
+void SPIRVAsmPrinter::emitFunctionHeader() {
+  if (ModuleSectionsEmitted == false) {
+    outputModuleSections();
+    ModuleSectionsEmitted = true;
+  }
+  // Get the subtarget from the current MachineFunction.
+  ST = &MF->getSubtarget<SPIRVSubtarget>();
+  TII = ST->getInstrInfo();
+  const Function &F = MF->getFunction();
+
+  if (isVerbose()) {
+    OutStreamer->getCommentOS()
+        << "-- Begin function "
+        << GlobalValue::dropLLVMManglingEscape(F.getName()) << '\n';
+  }
+
+  auto Section = getObjFileLowering().SectionForGlobal(&F, TM);
+  MF->setSection(Section);
+}
+
+void SPIRVAsmPrinter::outputOpFunctionEnd() {
+  MCInst FunctionEndInst;
+  FunctionEndInst.setOpcode(SPIRV::OpFunctionEnd);
+  outputMCInst(FunctionEndInst);
+}
+
+// Emit OpFunctionEnd at the end of MF and clear BBNumToRegMap.
+void SPIRVAsmPrinter::emitFunctionBodyEnd() {
+  outputOpFunctionEnd();
+  MAI->BBNumToRegMap.clear();
+}
+
+void SPIRVAsmPrinter::emitOpLabel(const MachineBasicBlock &MBB) {
+  MCInst LabelInst;
+  LabelInst.setOpcode(SPIRV::OpLabel);
+  LabelInst.addOperand(MCOperand::createReg(MAI->getOrCreateMBBRegister(MBB)));
+  outputMCInst(LabelInst);
+}
+
+void SPIRVAsmPrinter::emitBasicBlockStart(const MachineBasicBlock &MBB) {
+  // If it's the first MBB in MF, it has OpFunction and OpFunctionParameter, so
+  // OpLabel should be output after them.
+  if (MBB.getNumber() == MF->front().getNumber()) {
+    for (const MachineInstr &MI : MBB)
+      if (MI.getOpcode() == SPIRV::OpFunction)
+        return;
+    // TODO: this case should be checked by the verifier.
+    report_fatal_error("OpFunction is expected in the front MBB of MF");
+  }
+  emitOpLabel(MBB);
+}
+
+void SPIRVAsmPrinter::printOperand(const MachineInstr *MI, int OpNum,
+                                   raw_ostream &O) {
+  const MachineOperand &MO = MI->getOperand(OpNum);
+
+  switch (MO.getType()) {
+  case MachineOperand::MO_Register:
+    O << SPIRVInstPrinter::getRegisterName(MO.getReg());
+    break;
+
+  case MachineOperand::MO_Immediate:
+    O << MO.getImm();
+    break;
+
+  case MachineOperand::MO_FPImmediate:
+    O << MO.getFPImm();
+    break;
+
+  case MachineOperand::MO_MachineBasicBlock:
+    O << *MO.getMBB()->getSymbol();
+    break;
+
+  case MachineOperand::MO_GlobalAddress:
+    O << *getSymbol(MO.getGlobal());
+    break;
+
+  case MachineOperand::MO_BlockAddress: {
+    MCSymbol *BA = GetBlockAddressSymbol(MO.getBlockAddress());
+    O << BA->getName();
+    break;
+  }
+
+  case MachineOperand::MO_ExternalSymbol:
+    O << *GetExternalSymbolSymbol(MO.getSymbolName());
+    break;
+
+  case MachineOperand::MO_JumpTableIndex:
+  case MachineOperand::MO_ConstantPoolIndex:
+  default:
+    llvm_unreachable("<unknown operand type>");
+  }
+}
+
+bool SPIRVAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
+                                      const char *ExtraCode, raw_ostream &O) {
+  if (ExtraCode && ExtraCode[0])
+    return true; // Invalid instruction - SPIR-V does not have special modifiers
+
+  printOperand(MI, OpNo, O);
+  return false;
+}
+
+static bool isFuncOrHeaderInstr(const MachineInstr *MI,
+                                const SPIRVInstrInfo *TII) {
+  return TII->isHeaderInstr(*MI) || MI->getOpcode() == SPIRV::OpFunction ||
+         MI->getOpcode() == SPIRV::OpFunctionParameter;
+}
+
+void SPIRVAsmPrinter::outputMCInst(MCInst &Inst) {
+  OutStreamer->emitInstruction(Inst, *OutContext.getSubtargetInfo());
+}
+
+void SPIRVAsmPrinter::outputInstruction(const MachineInstr *MI) {
+  SPIRVMCInstLower MCInstLowering;
+  MCInst TmpInst;
+  MCInstLowering.lower(MI, TmpInst, MAI);
+  outputMCInst(TmpInst);
+}
+
+void SPIRVAsmPrinter::emitInstruction(const MachineInstr *MI) {
+  if (!MAI->getSkipEmission(MI))
+    outputInstruction(MI);
+
+  // Output OpLabel after OpFunction and OpFunctionParameter in the first MBB.
+  const MachineInstr *NextMI = MI->getNextNode();
+  if (!MAI->hasMBBRegister(*MI->getParent()) && isFuncOrHeaderInstr(MI, TII) &&
+      (!NextMI || !isFuncOrHeaderInstr(NextMI, TII))) {
+    assert(MI->getParent()->getNumber() == MF->front().getNumber() &&
+           "OpFunction is not in the front MBB of MF");
+    emitOpLabel(*MI->getParent());
+  }
+}
+
+void SPIRVAsmPrinter::outputModuleSection(SPIRV::ModuleSectionType MSType) {
+  for (MachineInstr *MI : MAI->getMSInstrs(MSType))
+    outputInstruction(MI);
+}
+
+void SPIRVAsmPrinter::outputDebugSourceAndStrings(const Module &M) {
+  // Output OpSource.
+  MCInst Inst;
+  Inst.setOpcode(SPIRV::OpSource);
+  Inst.addOperand(MCOperand::createImm(static_cast<unsigned>(MAI->SrcLang)));
+  Inst.addOperand(
+      MCOperand::createImm(static_cast<unsigned>(MAI->SrcLangVersion)));
+  outputMCInst(Inst);
+}
+
+void SPIRVAsmPrinter::outputOpMemoryModel() {
+  MCInst Inst;
+  Inst.setOpcode(SPIRV::OpMemoryModel);
+  Inst.addOperand(MCOperand::createImm(static_cast<unsigned>(MAI->Addr)));
+  Inst.addOperand(MCOperand::createImm(static_cast<unsigned>(MAI->Mem)));
+  outputMCInst(Inst);
+}
+
+// Before the OpEntryPoints' output, we need to add the entry point's
+// interfaces. The interface is a list of IDs of global OpVariable instructions.
+// These declare the set of global variables from a module that form
+// the interface of this entry point.
+void SPIRVAsmPrinter::outputEntryPoints() {
+  // Find all OpVariable IDs with required StorageClass.
+  DenseSet<Register> InterfaceIDs;
+  for (MachineInstr *MI : MAI->GlobalVarList) {
+    assert(MI->getOpcode() == SPIRV::OpVariable);
+    auto SC = static_cast<SPIRV::StorageClass>(MI->getOperand(2).getImm());
+    // Before version 1.4, the interface's storage classes are limited to
+    // the Input and Output storage classes. Starting with version 1.4,
+    // the interface's storage classes are all storage classes used in
+    // declaring all global variables referenced by the entry point call tree.
+    if (ST->getSPIRVVersion() >= 14 || SC == SPIRV::StorageClass::Input ||
+        SC == SPIRV::StorageClass::Output) {
+      MachineFunction *MF = MI->getMF();
+      Register Reg = MAI->getRegisterAlias(MF, MI->getOperand(0).getReg());
+      InterfaceIDs.insert(Reg);
+    }
+  }
+
+  // Output OpEntryPoints adding interface args to all of them.
+  for (MachineInstr *MI : MAI->getMSInstrs(SPIRV::MB_EntryPoints)) {
+    SPIRVMCInstLower MCInstLowering;
+    MCInst TmpInst;
+    MCInstLowering.lower(MI, TmpInst, MAI);
+    for (Register Reg : InterfaceIDs) {
+      assert(Reg.isValid());
+      TmpInst.addOperand(MCOperand::createReg(Reg));
+    }
+    outputMCInst(TmpInst);
+  }
+}
+
+void SPIRVAsmPrinter::outputExtFuncDecls() {
+  // Insert OpFunctionEnd after each declaration.
+  SmallVectorImpl<MachineInstr *>::iterator
+      I = MAI->getMSInstrs(SPIRV::MB_ExtFuncDecls).begin(),
+      E = MAI->getMSInstrs(SPIRV::MB_ExtFuncDecls).end();
+  for (; I != E; ++I) {
+    outputInstruction(*I);
+    if ((I + 1) == E || (*(I + 1))->getOpcode() == SPIRV::OpFunction)
+      outputOpFunctionEnd();
+  }
+}
+
+void SPIRVAsmPrinter::outputModuleSections() {
+  const Module *M = MMI->getModule();
+  // Get the global subtarget to output module-level info.
+  ST = static_cast<const SPIRVTargetMachine &>(TM).getSubtargetImpl();
+  TII = ST->getInstrInfo();
+  MAI = &SPIRVModuleAnalysis::MAI;
+  assert(ST && TII && MAI && M && "Module analysis is required");
+  // Output instructions according to the Logical Layout of a Module:
+  // TODO: 1,2. All OpCapability instructions, then optional OpExtension
+  // instructions.
+  // TODO: 3. Optional OpExtInstImport instructions.
+  // 4. The single required OpMemoryModel instruction.
+  outputOpMemoryModel();
+  // 5. All entry point declarations, using OpEntryPoint.
+  outputEntryPoints();
+  // 6. Execution-mode declarations, using OpExecutionMode or OpExecutionModeId.
+  // TODO:
+  // 7a. Debug: all OpString, OpSourceExtension, OpSource, and
+  // OpSourceContinued, without forward references.
+  outputDebugSourceAndStrings(*M);
+  // 7b. Debug: all OpName and all OpMemberName.
+  outputModuleSection(SPIRV::MB_DebugNames);
+  // 7c. Debug: all OpModuleProcessed instructions.
+  outputModuleSection(SPIRV::MB_DebugModuleProcessed);
+  // 8. All annotation instructions (all decorations).
+  outputModuleSection(SPIRV::MB_Annotations);
+  // 9. All type declarations (OpTypeXXX instructions), all constant
+  // instructions, and all global variable declarations. This section is
+  // the first section to allow use of: OpLine and OpNoLine debug information;
+  // non-semantic instructions with OpExtInst.
+  outputModuleSection(SPIRV::MB_TypeConstVars);
+  // 10. All function declarations (functions without a body).
+  outputExtFuncDecls();
+  // 11. All function definitions (functions with a body).
+  // This is done in regular function output.
+}
+
+bool SPIRVAsmPrinter::doInitialization(Module &M) {
+  ModuleSectionsEmitted = false;
+  // We need to call the parent's one explicitly.
+  return AsmPrinter::doInitialization(M);
+}
+
+// Force static initialization.
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeSPIRVAsmPrinter() {
+  RegisterAsmPrinter<SPIRVAsmPrinter> X(getTheSPIRV32Target());
+  RegisterAsmPrinter<SPIRVAsmPrinter> Y(getTheSPIRV64Target());
+}