[llvm-branch-commits] [llvm] [WIP][SPIRV][Debug Info] Add support for emitting DebugFunction debug info instructions (PR #183122)

[Marcos Maronas via llvm-branch-commits]

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@@ -155,6 +164,63 @@ Register SPIRVEmitNonSemanticDI::emitDIInstruction(
   return InstReg;
 }
 
+// Emit a DebugTypeFunction instruction for the given DISubroutineType.
+// This creates a SPIRV debug type function that represents the function
+// signature, including type flags, return type, and parameter types. Currently
+// only handles void functions with no parameters; type flags are not translated
+// (using 0 as a placeholder), and full parameter and return type support is
+// TODO.
+Register SPIRVEmitNonSemanticDI::emitDebugTypeFunction(
+    MachineRegisterInfo &MRI, MachineIRBuilder &MIRBuilder,
+    SPIRVGlobalRegistry *GR, const SPIRVTypeInst &VoidTy,
+    const SPIRVTypeInst &I32Ty, const SPIRVInstrInfo *TII,
+    const SPIRVRegisterInfo *TRI, const RegisterBankInfo *RBI,
+    MachineFunction &MF, DISubroutineType *FuncType, LLVMContext *Context) {
+  // TODO: Translate flags from the function type. Currently not translating
+  // flags, using 0 as a placeholder.
+  const Register TypeFlagsReg =
+      GR->buildConstantInt(0, MIRBuilder, I32Ty, false);
+
+  SmallVector<Register> TypeRegs;
+  TypeRegs.push_back(TypeFlagsReg);
+
+  // TODO: Handle parameters and return types
+  // void function with no parameters - use OpTypeVoid for return type
+  const SPIRVTypeInst OpTypeVoidInst =
+      GR->getOrCreateSPIRVType(Type::getVoidTy(*Context), MIRBuilder,
+                               SPIRV::AccessQualifier::ReadWrite, false);
+  const Register VoidTypeReg = GR->getSPIRVTypeID(OpTypeVoidInst);
+  TypeRegs.push_back(VoidTypeReg);
+
+  // Emit DebugTypeFunction instruction
+  const Register InstReg = MRI.createVirtualRegister(&SPIRV::IDRegClass);
+  MRI.setType(InstReg, LLT::scalar(32));
+  MachineInstrBuilder MIB =
+      MIRBuilder.buildInstr(SPIRV::OpExtInst)
+          .addDef(InstReg)
+          .addUse(GR->getSPIRVTypeID(VoidTy))
+          .addImm(static_cast<int64_t>(
+              SPIRV::InstructionSet::NonSemantic_Shader_DebugInfo_100))
+          .addImm(SPIRV::NonSemanticExtInst::DebugTypeFunction);
+  for (auto Reg : TypeRegs) {
+    MIB.addUse(Reg);
+  }
+  MIB.constrainAllUses(*TII, *TRI, *RBI);
+  GR->assignSPIRVTypeToVReg(VoidTy, InstReg, MF);
+  return InstReg;
+}
+
+// TODO: Support additional DebugFunction flags. Currently only FlagIsDefinition
+// is handled.
+uint64_t SPIRVEmitNonSemanticDI::getDebugFunctionFlags(const DISubprogram *SP) {
+  // Map flags - minimal implementation
+  // FlagIsDefinition = 1 << 3
+  uint64_t Flags = 0;
+  if (SP->isDefinition())
+    Flags |= (1 << 3); // FlagIsDefinition
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maarquitos14 wrote:

It'll be nice to have an enum for flags so that we don't need magic numbers.

https://github.com/llvm/llvm-project/pull/183122