1 files changed, 76 insertions, 0 deletions
diff --git a/llvm/test/DebugInfo/X86/tail-merge.ll b/llvm/test/DebugInfo/X86/tail-merge.ll
new file mode 100644
index 00000000000..d87866d58b8
--- /dev/null
+++ b/llvm/test/DebugInfo/X86/tail-merge.ll
@@ -0,0 +1,76 @@
+; RUN: llc %s -mtriple=x86_64-unknown-unknown -use-unknown-locations=true -o - | FileCheck %s
+
+; Generated with "clang -gline-tables-only -c -emit-llvm -o - | opt -sroa -S"
+; from source:
+;
+; extern int foo(int);
+; extern int bar(int);
+;
+; int test(int a, int b) {
+;   if(b)
+;     a += foo(a);
+;   else
+;     a += bar(a);
+;   return a;
+; }
+
+; When tail-merging the debug location of the common tail should be removed.
+
+; CHECK-LABEL: test:
+; CHECK: movl	%edi, [[REG:%.*]]
+; CHECK: testl	%esi, %esi
+; CHECK: je	[[ELSE:.LBB[0-9]+_[0-9]+]]
+; CHECK: .loc	1 6 10
+; CHECK: callq	foo
+; CHECK: jmp	[[TAIL:.LBB[0-9]+_[0-9]+]]
+; CHECK: [[ELSE]]:
+; CHECK: .loc	1 8 10
+; CHECK: callq	bar
+; CHECK: [[TAIL]]:
+; CHECK: .loc	1 0 0
+; CHECK: addl	[[REG]], %eax
+; CHECK: .loc	1 9 3
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+define i32 @test(i32 %a, i32 %b) !dbg !6 {
+entry:
+  %tobool = icmp ne i32 %b, 0, !dbg !8
+  br i1 %tobool, label %if.then, label %if.else, !dbg !8
+
+if.then:                                          ; preds = %entry
+  %call = call i32 @foo(i32 %a), !dbg !9
+  %add = add nsw i32 %a, %call, !dbg !10
+  br label %if.end, !dbg !11
+
+if.else:                                          ; preds = %entry
+  %call1 = call i32 @bar(i32 %a), !dbg !12
+  %add2 = add nsw i32 %a, %call1, !dbg !13
+  br label %if.end
+
+if.end:                                           ; preds = %if.else, %if.then
+  %a.addr.0 = phi i32 [ %add, %if.then ], [ %add2, %if.else ]
+  ret i32 %a.addr.0, !dbg !14
+}
+
+declare i32 @foo(i32)
+declare i32 @bar(i32)
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!3, !4}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "", isOptimized: false, runtimeVersion: 0, emissionKind: LineTablesOnly, enums: !2)
+!1 = !DIFile(filename: "test.c", directory: "")
+!2 = !{}
+!3 = !{i32 2, !"Dwarf Version", i32 4}
+!4 = !{i32 2, !"Debug Info Version", i32 3}
+!6 = distinct !DISubprogram(name: "test", scope: !1, file: !1, line: 4, type: !7, isLocal: false, isDefinition: true, scopeLine: 4, flags: DIFlagPrototyped, isOptimized: false, unit: !0, variables: !2)
+!7 = !DISubroutineType(types: !2)
+!8 = !DILocation(line: 5, column: 6, scope: !6)
+!9 = !DILocation(line: 6, column: 10, scope: !6)
+!10 = !DILocation(line: 6, column: 7, scope: !6)
+!11 = !DILocation(line: 6, column: 5, scope: !6)
+!12 = !DILocation(line: 8, column: 10, scope: !6)
+!13 = !DILocation(line: 8, column: 7, scope: !6)
+!14 = !DILocation(line: 9, column: 3, scope: !6)