[dsymutil] Relocate DW_TAG_label

dsymutil is not relocating the DW_AT_low_pc for a DW_TAG_label. This
patch fixes that and adds a test.

Differential revision: https://reviews.llvm.org/D99534

Author: JDevlieghere

llvm/lib/DWARFLinker/DWARFLinker.cpp

@@ -1088,7 +1088,8 @@ unsigned DWARFLinker::DIECloner::cloneAddressAttribute(
 
   if (AttrSpec.Attr == dwarf::DW_AT_low_pc) {
     if (Die.getTag() == dwarf::DW_TAG_inlined_subroutine ||
-        Die.getTag() == dwarf::DW_TAG_lexical_block)
+        Die.getTag() == dwarf::DW_TAG_lexical_block ||
+        Die.getTag() == dwarf::DW_TAG_label) {
       // The low_pc of a block or inline subroutine might get
       // relocated because it happens to match the low_pc of the
       // enclosing subprogram. To prevent issues with that, always use
@@ -1097,7 +1098,7 @@ unsigned DWARFLinker::DIECloner::cloneAddressAttribute(
                   ? Info.OrigLowPc
                   : Addr) +
              Info.PCOffset;
-    else if (Die.getTag() == dwarf::DW_TAG_compile_unit) {
+    } else if (Die.getTag() == dwarf::DW_TAG_compile_unit) {
       Addr = Unit.getLowPc();
       if (Addr == std::numeric_limits<uint64_t>::max())
         return 0;

llvm/test/tools/dsymutil/Inputs/private/tmp/label/label.o

@@ -0,0 +1,21 @@
+$ cat label.c
+int main(int argc, char **argv) {
+    if (argc) {
+        goto foobar;
+    }
+    return 1;
+foobar:
+    return 0;
+}
+
+$ clang -g label.c -c -o label.o
+$ clang label.o -o label.out
+
+RUN: dsymutil -oso-prepend-path %p/../Inputs %p/../Inputs/private/tmp/label/label.out -o %t.dSYM
+RUN: dwarfdump %t.dSYM | FileCheck %s
+
+CHECK:      DW_TAG_label
+CHECK-NEXT:   DW_AT_name    ("foobar")
+CHECK-NEXT:   DW_AT_decl_file       ("/tmp/label/label.c")
+CHECK-NEXT:   DW_AT_decl_line       (6)
+CHECK-NEXT:   DW_AT_low_pc  (0x0000000100003f9d)