[NFC][SimplifyCFG] Add basic test for debuginfo preservation of `ret` tail merging

diff --git a/llvm/test/Transforms/SimplifyCFG/return-merge.ll b/llvm/test/Transforms/SimplifyCFG/return-merge.ll
index 31df0bf..e1e35da 100644 (file)
--- a/llvm/test/Transforms/SimplifyCFG/return-merge.ll
+++ b/llvm/test/Transforms/SimplifyCFG/return-merge.ll
@@ -1,5 +1,6 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt < %s -simplifycfg -simplifycfg-require-and-preserve-domtree=1 -S | FileCheck %s
+; RUN: opt < %s -simplifycfg -simplifycfg-require-and-preserve-domtree=1 -S | FileCheck --check-prefixes=CHECK %s
+; RUN: opt < %s -debugify -simplifycfg -simplifycfg-require-and-preserve-domtree=1 -S | FileCheck --check-prefixes=DBGINFO %s
 
 define i32 @test1(i1 %C) {
 ; CHECK-LABEL: @test1(
@@ -7,6 +8,12 @@ define i32 @test1(i1 %C) {
 ; CHECK-NEXT:    [[SPEC_SELECT:%.*]] = select i1 [[C:%.*]], i32 1, i32 0
 ; CHECK-NEXT:    ret i32 [[SPEC_SELECT]]
 ;
+; DBGINFO-LABEL: @test1(
+; DBGINFO-NEXT:  entry:
+; DBGINFO-NEXT:    call void @llvm.dbg.value(metadata i32 0, metadata [[META9:![0-9]+]], metadata !DIExpression()), !dbg [[DBG11:![0-9]+]]
+; DBGINFO-NEXT:    [[SPEC_SELECT:%.*]] = select i1 [[C:%.*]], i32 1, i32 0, !dbg [[DBG11]]
+; DBGINFO-NEXT:    ret i32 [[SPEC_SELECT]], !dbg [[DBG12:![0-9]+]]
+;
 entry:
   br i1 %C, label %T, label %F
 T:              ; preds = %entry
@@ -20,6 +27,11 @@ define void @test2(i1 %C) {
 ; CHECK-NEXT:  T:
 ; CHECK-NEXT:    ret void
 ;
+; DBGINFO-LABEL: @test2(
+; DBGINFO-NEXT:  T:
+; DBGINFO-NEXT:    call void @llvm.dbg.value(metadata i32 0, metadata [[META15:![0-9]+]], metadata !DIExpression()), !dbg [[DBG16:![0-9]+]]
+; DBGINFO-NEXT:    ret void, !dbg [[DBG17:![0-9]+]]
+;
   br i1 %C, label %T, label %F
 T:              ; preds = %0
   ret void