flang][debug] Run AddDebugInfo before TargetRewrite.

[abidh]

This help us generate debug info that better represents the actual Fortran source code. It was briefly discussed here.

Fixes #108711.

[llvmbot]

@llvm/pr-subscribers-flang-driver

@llvm/pr-subscribers-flang-fir-hlfir

Author: Abid Qadeer (abidh)

Changes

This help us generate debug info that better represents the actual Fortran source code. It was briefly discussed here.

Fixes #108711.

---

Full diff: https://github.com/llvm/llvm-project/pull/114418.diff

3 Files Affected:

• (modified) flang/lib/Optimizer/Passes/Pipelines.cpp (+1-1)
• (modified) flang/test/Driver/mlir-debug-pass-pipeline.f90 (+2-2)
• (added) flang/test/Integration/debug-complex-2.f90 (+12)

diff --git a/flang/lib/Optimizer/Passes/Pipelines.cpp b/flang/lib/Optimizer/Passes/Pipelines.cpp
index 3c139f7e93405c..113225df991364 100644
--- a/flang/lib/Optimizer/Passes/Pipelines.cpp
+++ b/flang/lib/Optimizer/Passes/Pipelines.cpp
@@ -264,10 +264,10 @@ void createDefaultFIRCodeGenPassPipeline(mlir::PassManager &pm,
   addNestedPassToAllTopLevelOperations(pm, fir::createAbstractResultOpt);
   fir::addCodeGenRewritePass(
       pm, (config.DebugInfo != llvm::codegenoptions::NoDebugInfo));
+  fir::createDebugPasses(pm, config.DebugInfo, config.OptLevel, inputFilename);
   fir::addTargetRewritePass(pm);
   fir::addCompilerGeneratedNamesConversionPass(pm);
   fir::addExternalNameConversionPass(pm, config.Underscoring);
-  fir::createDebugPasses(pm, config.DebugInfo, config.OptLevel, inputFilename);
 
   if (config.VScaleMin != 0)
     pm.addPass(fir::createVScaleAttr({{config.VScaleMin, config.VScaleMax}}));
diff --git a/flang/test/Driver/mlir-debug-pass-pipeline.f90 b/flang/test/Driver/mlir-debug-pass-pipeline.f90
index e44f4e62a7148b..277f4795670a58 100644
--- a/flang/test/Driver/mlir-debug-pass-pipeline.f90
+++ b/flang/test/Driver/mlir-debug-pass-pipeline.f90
@@ -111,10 +111,10 @@
 
 ! ALL-NEXT: CodeGenRewrite
 ! ALL-NEXT:   (S) 0 num-dce'd - Number of operations eliminated
+! DEBUG-NEXT: AddDebugInfo
+! NO-DEBUG-NOT: AddDebugInfo
 ! ALL-NEXT: TargetRewrite
 ! ALL-NEXT: CompilerGeneratedNamesConversion
 ! ALL-NEXT: ExternalNameConversion
-! DEBUG-NEXT: AddDebugInfo
-! NO-DEBUG-NOT: AddDebugInfo
 ! ALL: FIRToLLVMLowering
 ! ALL-NOT: LLVMIRLoweringPass
diff --git a/flang/test/Integration/debug-complex-2.f90 b/flang/test/Integration/debug-complex-2.f90
new file mode 100644
index 00000000000000..c5f46d7b270b64
--- /dev/null
+++ b/flang/test/Integration/debug-complex-2.f90
@@ -0,0 +1,12 @@
+! RUN: %flang_fc1 -emit-llvm -debug-info-kind=standalone %s -o - | FileCheck  %s
+
+! Test that complex return type is correctly represented in debug.
+complex function fn(a)
+    complex, intent(in) :: a
+    fn = a
+end function
+
+! CHECK-DAG: ![[CMPLX:.*]] = !DIBasicType(name: "complex", size: 64, encoding: DW_ATE_complex_float)
+! CHECK-DAG: ![[SR_TY:.*]] = !DISubroutineType(cc: DW_CC_normal, types: ![[TYPES:.*]])
+! CHECK-DAG: ![[TYPES]] = !{![[CMPLX]], ![[CMPLX]]}
+! CHECK-DAG: !DISubprogram(name: "fn"{{.*}}type: ![[SR_TY]]{{.*}})

[tarunprabhu]

Thanks Abid.

[tblah]

LGTM

[jeanPerier]

Thanks, LGTM