[llvm-readobj][XCOFF] Print the length of the string table.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D107333

Author: Esme-Yi

llvm/test/tools/llvm-readobj/XCOFF/string-table.yaml

@@ -5,6 +5,7 @@
 # RUN: llvm-readobj --string-table %t1 | FileCheck %s --check-prefix=BASIC
 
 # BASIC:      StringTable {
+# BASIC-NEXT:   Length: 16
 # BASIC-NEXT:   [     4]   name2
 # BASIC-NEXT:   [     a]   name1
 # BASIC-NEXT: }
@@ -21,6 +22,7 @@ Symbols:
 # RUN: llvm-readobj --string-table %t2 | FileCheck %s --check-prefix=SINGLE-BYTE
 
 # SINGLE-BYTE:      StringTable {
+# SINGLE-BYTE-NEXT:   Length: 6
 # SINGLE-BYTE-NEXT:   [     4]   n
 # SINGLE-BYTE-NEXT: }
 
@@ -35,6 +37,7 @@ Symbols:
 # RUN: llvm-readobj --string-table %t3 | FileCheck %s --check-prefix=NO-STRTBL
 
 # NO-STRTBL:      StringTable {
+# NO-STRTBL-NEXT:   Length: 0
 # NO-STRTBL-NEXT: }
 
 --- !XCOFF

llvm/test/tools/yaml2obj/XCOFF/basic-doc64.yaml

@@ -135,6 +135,7 @@ Symbols:
 # CHECK64-NEXT:   }
 # CHECK64-NEXT: ]
 # CHECK64-NEXT: StringTable {
+# CHECK64-NEXT:   Length: 28
 # CHECK64-NEXT:   [     4]   .text
 # CHECK64-NEXT:   [     a]   .abs
 # CHECK64-NEXT:   [     f]   .undef

llvm/test/tools/yaml2obj/XCOFF/long-symbol-name.yaml

@@ -24,6 +24,7 @@
 # CHECK-NEXT:   }
 # CHECK-NEXT: ]
 # CHECK-NEXT: StringTable {
+# CHECK-NEXT:   Length: 14
 # CHECK-NEXT:   [     4]   .longname
 # CHECK-NEXT: }
 

llvm/tools/llvm-readobj/XCOFFDumper.cpp

@@ -460,9 +460,11 @@ void XCOFFDumper::printSymbols() {
 void XCOFFDumper::printStringTable() {
   DictScope DS(W, "StringTable");
   StringRef StrTable = Obj.getStringTable();
+  size_t StrTabSize = StrTable.size();
+  W.printNumber("Length", StrTabSize);
   // Print strings from the fifth byte, since the first four bytes contain the
   // length (in bytes) of the string table (including the length field).
-  if (StrTable.size() > 4)
+  if (StrTabSize > 4)
     printAsStringList(StrTable, 4);
 }