[RemoveDIs][MLIR] Don't process debug records in the LLVM-IR translator (#89735)

We are almost ready to enable the use of debug records everywhere in
LLVM by default; part of the prep-work for this means ensuring that
every tool supports them. Every tool in the `llvm/` project supports
them, front-ends that use the `DIBuilder` will support them, and as far
as I can tell, the only other tool in the LLVM repo that needs to
support them but doesn't is `mlir-translate`. This patch trivially
unblocks them by converting from debug records to debug intrinsics
before translating a module.

Author: SLTozer

mlir/lib/Target/LLVMIR/ConvertFromLLVMIR.cpp

@@ -56,6 +56,10 @@ void registerFromLLVMIRTranslation() {
         if (llvm::verifyModule(*llvmModule, &llvm::errs()))
           return nullptr;
 
+        // Debug records are not currently supported in the LLVM IR translator.
+        if (llvmModule->IsNewDbgInfoFormat)
+          llvmModule->convertFromNewDbgValues();
+
         return translateLLVMIRToModule(std::move(llvmModule), context,
                                        emitExpensiveWarnings,
                                        dropDICompositeTypeElements);

mlir/test/Target/LLVMIR/Import/import-failure.ll

@@ -64,12 +64,12 @@ define void @unhandled_intrinsic() gc "example" {
 declare void @llvm.dbg.value(metadata, metadata, metadata)
 
 ; CHECK:      import-failure.ll
-; CHECK-SAME: warning: dropped intrinsic: call void @llvm.dbg.value(metadata !DIArgList(i64 %{{.*}}, i64 undef), metadata !3, metadata !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 1, DW_OP_constu, 1, DW_OP_mul, DW_OP_plus, DW_OP_stack_value))
+; CHECK-SAME: warning: dropped intrinsic: tail call void @llvm.dbg.value(metadata !DIArgList(i64 %{{.*}}, i64 undef), metadata !3, metadata !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 1, DW_OP_constu, 1, DW_OP_mul, DW_OP_plus, DW_OP_stack_value))
 ; CHECK:      import-failure.ll
-; CHECK-SAME: warning: dropped intrinsic: call void @llvm.dbg.value(metadata !6, metadata !3, metadata !DIExpression())
+; CHECK-SAME: warning: dropped intrinsic: tail call void @llvm.dbg.value(metadata !6, metadata !3, metadata !DIExpression())
 define void @unsupported_argument(i64 %arg1) {
-  call void @llvm.dbg.value(metadata !DIArgList(i64 %arg1, i64 undef), metadata !3, metadata !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 1, DW_OP_constu, 1, DW_OP_mul, DW_OP_plus, DW_OP_stack_value)), !dbg !5
-  call void @llvm.dbg.value(metadata !6, metadata !3, metadata !DIExpression()), !dbg !5
+  tail call void @llvm.dbg.value(metadata !DIArgList(i64 %arg1, i64 undef), metadata !3, metadata !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 1, DW_OP_constu, 1, DW_OP_mul, DW_OP_plus, DW_OP_stack_value)), !dbg !5
+  tail call void @llvm.dbg.value(metadata !6, metadata !3, metadata !DIExpression()), !dbg !5
   ret void
 }