Make llvm-dwarfdump -name work on type units.

[JDevlieghere]

Cool, thanks Paul. LGTM

llvm/test/tools/llvm-dwarfdump/X86/typeunit-name.s

+# Demonstrate that -name works with type units.
+# RUN: llvm-mc -triple x86_64-unknown-linux %s -filetype=obj -o %t.o
+# RUN: llvm-dwarfdump -name=V4_type_unit -name=V5_split_type_unit %t.o | FileCheck %s
+#
+# The names should appear twice, once for the unit and once for the type DIE,
+# because we give them the same name.
+# CHECK: V4_type_unit
+# CHECK: V4_type_unit
+# CHECK: V5_split_type_unit
+# CHECK: V5_split_type_unit
+
+        .section .debug_str,"MS",@progbits,1
+str_TU_4:
+        .asciz "V4_type_unit"
+
+        .section .debug_str.dwo,"MS",@progbits,1
+dwo_TU_5:
+        .asciz "V5_split_type_unit"
+
+# Abbrev section for the normal type unit.
+        .section .debug_abbrev,"",@progbits
+        .byte 0x01  # Abbrev code
+        .byte 0x41  # DW_TAG_type_unit
+        .byte 0x01  # DW_CHILDREN_yes
+        .byte 0x03  # DW_AT_name
+        .byte 0x0e  # DW_FORM_strp
+        .byte 0x00  # EOM(1)
+        .byte 0x00  # EOM(2)
+        .byte 0x02  # Abbrev code
+        .byte 0x13  # DW_TAG_structure_type
+        .byte 0x00  # DW_CHILDREN_no (no members)
+        .byte 0x03  # DW_AT_name
+        .byte 0x0e  # DW_FORM_strp
+        .byte 0x00  # EOM(1)
+        .byte 0x00  # EOM(2)
+        .byte 0x00  # EOM(3)
+
+# And a .dwo copy for the .dwo section.
+        .section .debug_abbrev.dwo,"",@progbits
+        .byte 0x01  # Abbrev code
+        .byte 0x41  # DW_TAG_type_unit
+        .byte 0x01  # DW_CHILDREN_yes
+        .byte 0x03  # DW_AT_name
+        .byte 0x0e  # DW_FORM_strp
+        .byte 0x00  # EOM(1)
+        .byte 0x00  # EOM(2)
+        .byte 0x02  # Abbrev code
+        .byte 0x13  # DW_TAG_structure_type
+        .byte 0x00  # DW_CHILDREN_no (no members)
+        .byte 0x03  # DW_AT_name
+        .byte 0x0e  # DW_FORM_strp
+        .byte 0x00  # EOM(1)
+        .byte 0x00  # EOM(2)
+        .byte 0x00  # EOM(3)
+
+        .section .debug_types,"",@progbits
+
+# DWARF v4 Type unit header. Normal/split are identical so we do only one.
+TU_4_start:
+        .long  TU_4_end-TU_4_version  # Length of Unit
+TU_4_version:
+        .short 4               # DWARF version number
+        .long .debug_abbrev    # Offset Into Abbrev. Section
+        .byte 8                # Address Size (in bytes)
+        .quad 0x0011223344556677 # Type Signature
+        .long TU_4_type-TU_4_start # Type offset
+# The type-unit DIE, which has a name.
+        .byte 1
+        .long str_TU_4
+# The type DIE, which has the same name.
+TU_4_type:
+        .byte 2
+        .long str_TU_4
+        .byte 0 # NULL
+        .byte 0 # NULL
+TU_4_end:
+
+        .section .debug_types.dwo,"",@progbits
+# FIXME: DWARF v5 wants type units in .debug_info[.dwo] not .debug_types[.dwo].
+
+# DWARF v5 split type unit header.
+TU_split_5_start:
+        .long  TU_split_5_end-TU_split_5_version  # Length of Unit
+TU_split_5_version:
+        .short 5               # DWARF version number
+        .byte 6                # DWARF Unit Type
+        .byte 8                # Address Size (in bytes)
+        .long .debug_abbrev.dwo    # Offset Into Abbrev. Section
+        .quad 0x8899aabbccddeeff # Type Signature
+        .long TU_split_5_type-TU_split_5_start  # Type offset
+# The type-unit DIE, which has a name.
+        .byte 1
+        .long dwo_TU_5
+# The type DIE, which has the same name.
+TU_split_5_type:
+        .byte 2
+        .long dwo_TU_5
+        .byte 0 # NULL
+        .byte 0 # NULL
+TU_split_5_end:

llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp

if (Lookup)
     return lookup(DICtx, Lookup, OS);
 
   // Handle the --name option.
   if (!Name.empty()) {
     StringSet<> Names;
     for (auto name : Name)
       Names.insert((IgnoreCase && !UseRegex) ? StringRef(name).lower() : name);
 
-    filterByName(Names, DICtx.compile_units(), OS);
-    filterByName(Names, DICtx.dwo_compile_units(), OS);
+    filterByName(Names, DICtx.normal_units(), OS);
+    filterByName(Names, DICtx.dwo_units(), OS);
     return true;
   }
 
   // Handle the --find option and lower it to --debug-info=<offset>.
   if (!Find.empty()) {
     filterByAccelName(Find, DICtx, OS);
     return true;
   }