[Mlir-commits] [mlir] [MLIR][LLVM] Avoid creating unused NameLocs for imported functions (PR #163506)

[Christian Ulmann]

https://github.com/Dinistro created https://github.com/llvm/llvm-project/pull/163506

This commit removes the creation of NameLocs when importing locations for LLVM IR functions. This made the generated fused location more complex by adding no valuable additional information to it. Note that removing it has no effect on the roundtrip from LLVM IR back to LLVM IR.

>From bb3985f865d92d8aaa57a02ae07317880f950f3a Mon Sep 17 00:00:00 2001
From: Christian Ulmann <christian.ulmann at nextsilicon.com>
Date: Wed, 15 Oct 2025 08:29:07 +0200
Subject: [PATCH] [MLIR][LLVM] Avoid creating unused NameLocs for imported
 functions

This commit removes the creation of NameLocs when importing locations
for LLVM IR functions. This made the generated fused location more
complex by adding no valuable additional information to it. Note that
removing it has no effect on the roundtrip from LLVM IR back to LLVM IR.
---
 mlir/lib/Target/LLVMIR/DebugImporter.cpp     | 4 +---
 mlir/test/Target/LLVMIR/Import/debug-info.ll | 3 +--
 2 files changed, 2 insertions(+), 5 deletions(-)

diff --git a/mlir/lib/Target/LLVMIR/DebugImporter.cpp b/mlir/lib/Target/LLVMIR/DebugImporter.cpp
index 8b0326518770d..6c4918404845d 100644
--- a/mlir/lib/Target/LLVMIR/DebugImporter.cpp
+++ b/mlir/lib/Target/LLVMIR/DebugImporter.cpp
@@ -34,11 +34,9 @@ Location DebugImporter::translateFuncLocation(llvm::Function *func) {
     return UnknownLoc::get(context);
 
   // Add a fused location to link the subprogram information.
-  StringAttr funcName = StringAttr::get(context, subprogram->getName());
   StringAttr fileName = StringAttr::get(context, subprogram->getFilename());
   return FusedLocWith<DISubprogramAttr>::get(
-      {NameLoc::get(funcName),
-       FileLineColLoc::get(fileName, subprogram->getLine(), /*column=*/0)},
+      {FileLineColLoc::get(fileName, subprogram->getLine(), /*column=*/0)},
       translate(subprogram), context);
 }
 
diff --git a/mlir/test/Target/LLVMIR/Import/debug-info.ll b/mlir/test/Target/LLVMIR/Import/debug-info.ll
index e056e43a0982c..61376b8f648ec 100644
--- a/mlir/test/Target/LLVMIR/Import/debug-info.ll
+++ b/mlir/test/Target/LLVMIR/Import/debug-info.ll
@@ -240,11 +240,10 @@ define void @subprogram() !dbg !3 {
 define void @func_loc() !dbg !3 {
   ret void
 }
-; CHECK-DAG: #[[NAME_LOC:.+]] = loc("func_loc")
 ; CHECK-DAG: #[[FILE_LOC:.+]] = loc("debug-info.ll":42:0)
 ; CHECK-DAG: #[[SP:.+]] =  #llvm.di_subprogram<id = distinct[{{.*}}]<>, compileUnit = #{{.*}}, scope = #{{.*}}, name = "func_loc", file = #{{.*}}, line = 42, subprogramFlags = Definition>
 
-; CHECK: loc(fused<#[[SP]]>[#[[NAME_LOC]], #[[FILE_LOC]]]
+; CHECK: loc(fused<#[[SP]]>[#[[FILE_LOC]]]
 
 !llvm.dbg.cu = !{!1}
 !llvm.module.flags = !{!0}