diff --git a/lib/Target/BPF/BTFDebug.cpp b/lib/Target/BPF/BTFDebug.cpp
index 8fc64d8..ca3a8c5 100644
--- a/lib/Target/BPF/BTFDebug.cpp
+++ b/lib/Target/BPF/BTFDebug.cpp
@@ -493,7 +493,7 @@
   auto File = SP->getFile();
   std::string FileName;
 
-  if (File->getDirectory().size())
+  if (!File->getFilename().startswith("/") && File->getDirectory().size())
     FileName = File->getDirectory().str() + "/" + File->getFilename().str();
   else
     FileName = File->getFilename();
diff --git a/test/CodeGen/BPF/BTF/filename.ll b/test/CodeGen/BPF/BTF/filename.ll
new file mode 100644
index 0000000..d0ada61
--- /dev/null
+++ b/test/CodeGen/BPF/BTF/filename.ll
@@ -0,0 +1,81 @@
+; RUN: llc -march=bpfel -filetype=asm -o - %s | FileCheck -check-prefixes=CHECK %s
+; RUN: llc -march=bpfeb -filetype=asm -o - %s | FileCheck -check-prefixes=CHECK %s
+
+; Source code:
+;   int test() { return 0; }
+; Compilation flag:
+;   clang -target bpf -O2 -g -S -emit-llvm t.c
+
+; Function Attrs: norecurse nounwind readnone uwtable
+define dso_local i32 @test() local_unnamed_addr #0 !dbg !7 {
+  ret i32 0, !dbg !11
+}
+
+; CHECK:             .section        .BTF,"",@progbits
+; CHECK-NEXT:        .short  60319                   # 0xeb9f
+; CHECK-NEXT:        .byte   1
+; CHECK-NEXT:        .byte   0
+; CHECK-NEXT:        .long   24
+; CHECK-NEXT:        .long   0
+; CHECK-NEXT:        .long   40
+; CHECK-NEXT:        .long   40
+; CHECK-NEXT:        .long   35
+; CHECK-NEXT:        .long   0                       # BTF_KIND_FUNC_PROTO(id = 1)
+; CHECK-NEXT:        .long   218103808               # 0xd000000
+; CHECK-NEXT:        .long   2
+; CHECK-NEXT:        .long   26                      # BTF_KIND_INT(id = 2)
+; CHECK-NEXT:        .long   16777216                # 0x1000000
+; CHECK-NEXT:        .long   4
+; CHECK-NEXT:        .long   16777248                # 0x1000020
+; CHECK-NEXT:        .long   30                      # BTF_KIND_FUNC(id = 3)
+; CHECK-NEXT:        .long   201326592               # 0xc000000
+; CHECK-NEXT:        .long   1
+; CHECK-NEXT:        .byte   0                       # string offset=0
+; CHECK-NEXT:        .ascii  ".text"                 # string offset=1
+; CHECK-NEXT:        .byte   0
+; CHECK-NEXT:        .ascii  "/home/yhs/ttmp/t.c"    # string offset=7
+; CHECK-NEXT:        .byte   0
+; CHECK-NEXT:        .ascii  "int"                   # string offset=26
+; CHECK-NEXT:        .byte   0
+; CHECK-NEXT:        .ascii  "test"                  # string offset=30
+; CHECK-NEXT:        .byte   0
+; CHECK-NEXT:        .section        .BTF.ext,"",@progbits
+; CHECK-NEXT:        .short  60319                   # 0xeb9f
+; CHECK-NEXT:        .byte   1
+; CHECK-NEXT:        .byte   0
+; CHECK-NEXT:        .long   24
+; CHECK-NEXT:        .long   0
+; CHECK-NEXT:        .long   20
+; CHECK-NEXT:        .long   20
+; CHECK-NEXT:        .long   28
+; CHECK-NEXT:        .long   8                       # FuncInfo
+; CHECK-NEXT:        .long   1                       # FuncInfo section string offset=1
+; CHECK-NEXT:        .long   1
+; CHECK-NEXT:        .long   .Lfunc_begin{{[0-9]+}}
+; CHECK-NEXT:        .long   3
+; CHECK-NEXT:        .long   16                      # LineInfo
+; CHECK-NEXT:        .long   1                       # LineInfo section string offset=1
+; CHECK-NEXT:        .long   1
+; CHECK-NEXT:        .long   .Ltmp{{[0-9]+}}
+; CHECK-NEXT:        .long   7
+; CHECK-NEXT:        .long   0
+; CHECK-NEXT:        .long   1038                    # Line 1 Col 14
+
+attributes #0 = { norecurse nounwind readnone uwtable "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+fxsr,+mmx,+sse,+sse2,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" }
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!3, !4, !5}
+!llvm.ident = !{!6}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 8.0.20181009 ", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, nameTableKind: None)
+!1 = !DIFile(filename: "/home/yhs/ttmp/t.c", directory: "/home/yhs/ttmp")
+!2 = !{}
+!3 = !{i32 2, !"Dwarf Version", i32 4}
+!4 = !{i32 2, !"Debug Info Version", i32 3}
+!5 = !{i32 1, !"wchar_size", i32 4}
+!6 = !{!"clang version 8.0.20181009 "}
+!7 = distinct !DISubprogram(name: "test", scope: !1, file: !1, line: 1, type: !8, isLocal: false, isDefinition: true, scopeLine: 1, isOptimized: true, unit: !0, retainedNodes: !2)
+!8 = !DISubroutineType(types: !9)
+!9 = !{!10}
+!10 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+!11 = !DILocation(line: 1, column: 14, scope: !7)