[PATCH] D61180: [yaml2obj] - Treat integer symbol names as explicit st_name value.

[George Rimar via Phabricator via llvm-commits]

grimar created this revision.
grimar added a reviewer: jhenderson.
Herald added a subscriber: jakehehrlich.

In some cases it is useful to explicitly set symbol's st_name value.
For example, I am using it in a patch for LLD to remove the broken
binary from a test case and replace it with a YAML test.


https://reviews.llvm.org/D61180

Files:
  test/tools/yaml2obj/symbol-name.yaml
  tools/yaml2obj/yaml2elf.cpp


Index: tools/yaml2obj/yaml2elf.cpp
===================================================================
--- tools/yaml2obj/yaml2elf.cpp
+++ tools/yaml2obj/yaml2elf.cpp
@@ -480,8 +480,18 @@
   for (const auto &Sym : Symbols) {
     Elf_Sym Symbol;
     zero(Symbol);
-    if (!Sym.Name.empty())
-      Symbol.st_name = Strtab.getOffset(Sym.Name);
+
+    // If name described in YAML as an integer, we assume it is an offset and
+    // use it. It is useful for preparing broken objects. Otherwise, we treat it
+    // as a string name and add to the string table builder.
+    if (!Sym.Name.empty()) {
+      unsigned SymName = 0;
+      if (!to_integer(Sym.Name, SymName))
+        Symbol.st_name = Strtab.getOffset(Sym.Name);
+      else
+        Symbol.st_name = SymName;
+    }
+
     Symbol.setBindingAndType(Sym.Binding, Sym.Type);
     if (!Sym.Section.empty()) {
       unsigned Index;
Index: test/tools/yaml2obj/symbol-name.yaml
===================================================================
--- /dev/null
+++ test/tools/yaml2obj/symbol-name.yaml
@@ -0,0 +1,20 @@
+# RUN: yaml2obj %s > %t
+# RUN: llvm-readobj --symbols %t | FileCheck %s
+
+# Check we are able to use integers for symbol names and
+# yaml2obj use them as explicit st_name value for symbols.
+
+# CHECK: Name: test (1)
+# CHECK: Name: test (1)
+# CHECK: Name: est (2)
+
+!ELF
+FileHeader:
+  Class:     ELFCLASS64
+  Data:      ELFDATA2LSB
+  Type:      ET_REL
+  Machine:   EM_X86_64
+Symbols:
+  - Name:    test
+  - Name:    1
+  - Name:    2


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