[llvm] [BranchFolder] Fix missing debug info with tail merging (PR #94715)

[Jeremy Morse via llvm-commits]

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@@ -0,0 +1,99 @@
+# Generated with
+#
+# bin/llc -stop-before=branch-folder test.ll
+# 
+# target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
+# target triple = "x86_64-grtev4-linux-gnu"
+#
+# define i32 @main(i1 %0) {
+# entry:
+#   br i1 %0, label %1, label %2
+#
+# 1:                                                ; preds = %entry
+#   store i64 1, ptr null, align 1
+#   br label %3, !dbg !3
+#
+# 2:                                                ; preds = %entry
+#   store i64 0, ptr null, align 1
+#   br label %3
+#
+# 3:                                                ; preds = %2, %1
+#   ret i32 0
+# }
+#
+# !llvm.dbg.cu = !{!0}
+# !llvm.module.flags = !{!2}
+# 
+# !0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !1, producer: "", isOptimized: true, runtimeVersion: 0, emissionKind: LineTablesOnly, nameTableKind: None)
+# !1 = !DIFile(filename: "foo.c", directory: "/tmp", checksumkind: CSK_MD5, checksum: "2d07c91bb9d9c2fa4eee31a1aeed20e3")
+# !2 = !{i32 2, !"Debug Info Version", i32 3}
+# !3 = !DILocation(line: 17, column: 3, scope: !4)
+# !4 = distinct !DISubprogram(name: "main", scope: !1, file: !1, line: 6, type: !5, scopeLine: 6, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0)
+# !5 = !DISubroutineType(types: !6)
+# !6 = !{}
+#
+# RUN: llc -o - %s -mtriple=x86_64-unknown-linux-gnu --run-pass=branch-folder -enable-tail-merge | FileCheck %s
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jmorse wrote:

Could you move the RUN line to the top of the file -- it's a convention with existing MRI tests.

https://github.com/llvm/llvm-project/pull/94715