[llvm-readobj] Dump DT_USED value as string like GNU readelf does

Reviewers: jhenderson

Reviewed By: jhenderson

Subscribers: rupprecht, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D59089

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@355600 91177308-0d34-0410-b5e6-96231b3b80d8

Author: higuoxing

test/tools/llvm-readobj/elf-dynamic-tags.test

@@ -3,7 +3,7 @@
 # RUN: llvm-readobj --dynamic-table %t | FileCheck %s --check-prefix=LLVM
 # RUN: llvm-readelf --dynamic-table %t | FileCheck %s --check-prefix=GNU
 
-# LLVM:      DynamicSection [ (60 entries)
+# LLVM:      DynamicSection [ (61 entries)
 # LLVM-NEXT:   Tag                Type                 Name/Value
 # LLVM-NEXT:   0x0000000000000001 NEEDED               Shared library: [D]
 # LLVM-NEXT:   0x0000000000000002 PLTRELSZ             16 (bytes)
@@ -60,14 +60,15 @@
 # LLVM-NEXT:   0x000000006FFFFFFE VERNEED              0x1000
 # LLVM-NEXT:   0x000000006FFFFFFF VERNEEDNUM           0
 # LLVM-NEXT:   0x000000007FFFFFFD AUXILIARY            Auxiliary library: [D]
+# LLVM-NEXT:   0x000000007FFFFFFE USED                 Not needed object: [U]
 # LLVM-NEXT:   0x000000007FFFFFFF FILTER               Filter library: [U]
 # LLVM-NEXT:   0x0000000012345678 unknown              0x8765432187654321
 # LLVM-NEXT:   0x000000006ABCDEF0 unknown              0x9988776655443322
 # LLVM-NEXT:   0x0000000076543210 unknown              0x5555666677778888
 # LLVM-NEXT:   0x0000000000000000 NULL                 0x0
 # LLVM-NEXT: ]
 
-# GNU:      DynamicSection [ (60 entries)
+# GNU:      DynamicSection [ (61 entries)
 # GNU-NEXT:   Tag                Type                 Name/Value
 # GNU-NEXT:   0x0000000000000001 NEEDED               Shared library: [D]
 # GNU-NEXT:   0x0000000000000002 PLTRELSZ             16 (bytes)
@@ -124,6 +125,7 @@
 # GNU-NEXT:   0x000000006ffffffe VERNEED              0x1000
 # GNU-NEXT:   0x000000006fffffff VERNEEDNUM           0
 # GNU-NEXT:   0x000000007ffffffd AUXILIARY            Auxiliary library: [D]
+# GNU-NEXT:   0x000000007ffffffe USED                 Not needed object: [U]
 # GNU-NEXT:   0x000000007fffffff FILTER               Filter library: [U]
 # GNU-NEXT:   0x0000000012345678 unknown              0x8765432187654321
 # GNU-NEXT:   0x000000006abcdef0 unknown              0x9988776655443322
@@ -257,6 +259,8 @@ Sections:
         Value: 0x0
       - Tag:   DT_AUXILIARY
         Value: 0x1
+      - Tag:   DT_USED
+        Value: 0x3
       - Tag:   DT_FILTER
         Value: 0x3
       # Show behaviour for unknown values in special and un-marked ranges.

tools/llvm-readobj/ELFDumper.cpp

@@ -1876,6 +1876,9 @@ void ELFDumper<ELFT>::printValue(uint64_t Type, uint64_t Value) {
   case DT_AUXILIARY:
     printLibrary(OS, "Auxiliary library", getDynamicString(Value));
     break;
+  case DT_USED:
+    printLibrary(OS, "Not needed object", getDynamicString(Value));
+    break;
   case DT_FILTER:
     printLibrary(OS, "Filter library", getDynamicString(Value));
     break;