Add symbol version support to llvm-ifs

llvm/docs/CommandGuide/llvm-ifs.rst

@@ -40,6 +40,12 @@ by the :program:`llvm-ifs`:
     - { Name: sym2, Type: Func, Weak: false }
     - { Name: sym3, Type: TLS }
     - { Name: sym4, Type: Unknown, Warning: foo }
+    - { Name: sym5, Version: VER_1, Type: Func }
+  VersionDefinitions: /* Optional */
+    - { Name: libtest.so }
+    - { Name: VER_1 }
+  VersionRequirements: /* Optional */
+    - { File: libc.so.6, Names: [ GLIBC_2.14, GLIBC_2.4, GLIBC_2.2.5, GLIBC_2.3.4 ] }
   ...
 
 * ``IFSVersion``: Version of the IFS file for reader compatibility.
@@ -67,6 +73,10 @@ by the :program:`llvm-ifs`:
 
   + ``Warning`` (optional): Warning text to output when this symbol is linked against.
 
+* ``VersionDefinitions`` (optional): A collection of symbol versions defined in this shared object file.
+
+* ``VersionRequirements`` (optional): A collection of symbol versions defined in external shared objects that this library depends on.
+
 This YAML based text format contains everything that is needed to generate a
 linkable ELF shared object as well as an Apple TAPI format file. The ordering
 of symbols is sorted, so these files can be easily compared using diff tools.
@@ -81,12 +91,20 @@ A minimum ELF file that can be used by linker should have following sections pro
 
 * ELF header.
 
+* Program headers. (optional)
+
 * Section headers.
 
 * Dynamic symbol table (``.dynsym`` section).
 
 * Dynamic string table (``.dynstr`` section).
 
+* Version symbol table (``.gnu.version`` section). (optional)
+
+* Version definition table (``.gnu.version_d`` section). (optional)
+
+* Version requirement table (``.gnu.version_r`` section). (optional)
+
 * Dynamic table (``.dynamic`` section).
 
   + ``DT_SYMTAB`` entry.
@@ -99,6 +117,12 @@ A minimum ELF file that can be used by linker should have following sections pro
 
   + ``DT_SONAME`` entry. (optional)
 
+  + ``DT_VERSYM`` entry. (optional)
+
+  + ``DT_VERDEF`` entry. (optional)
+
+  + ``DT_VERNEED`` entry. (optional)
+
 * Section header string table (``.shstrtab`` section)
 
 This ELF file may have compatibility issues with ELF analysis tools that rely on the program headers.
@@ -163,7 +187,7 @@ OPTIONS
  triple in the output IFS file. If the value matches the target information
  from the object file, this value will be used in the 'Target:' filed in the
  generated IFS. If it conflicts with the input object file, an error will be
- reported and the program will stop. 
+ reported and the program will stop.
 
 .. option:: --hint-ifs-target
 

llvm/include/llvm/InterfaceStub/IFSStub.h

@@ -52,8 +52,10 @@ enum class IFSBitWidthType {
 
 struct IFSSymbol {
   IFSSymbol() = default;
-  explicit IFSSymbol(std::string SymbolName) : Name(std::move(SymbolName)) {}
+  explicit IFSSymbol(std::string SymbolName, std::string SymVer)
+      : Name(std::move(SymbolName)), Version(std::move(SymVer)) {}
   std::string Name;
+  std::string Version;
   std::optional<uint64_t> Size;
   IFSSymbolType Type = IFSSymbolType::NoType;
   bool Undefined = false;
@@ -62,6 +64,36 @@ struct IFSSymbol {
   bool operator<(const IFSSymbol &RHS) const { return Name < RHS.Name; }
 };
 
+struct IFSVerDef {
+  std::string Name;
+  std::vector<std::string> Parents;
+};
+
+inline bool operator==(const IFSVerDef &Lhs, const IFSVerDef &Rhs) {
+  if (Lhs.Name != Rhs.Name || Lhs.Parents != Rhs.Parents)
+    return false;
+  return true;
+}
+
+inline bool operator!=(const IFSVerDef &Lhs, const IFSVerDef &Rhs) {
+  return !(Lhs == Rhs);
+}
+
+struct IFSVerNeed {
+  std::string File;
+  std::vector<std::string> Names;
+};
+
+inline bool operator==(const IFSVerNeed &Lhs, const IFSVerNeed &Rhs) {
+  if (Lhs.File != Rhs.File || Lhs.Names != Rhs.Names)
+    return false;
+  return true;
+}
+
+inline bool operator!=(const IFSVerNeed &Lhs, const IFSVerNeed &Rhs) {
+  return !(Lhs == Rhs);
+}
+
 struct IFSTarget {
   std::optional<std::string> Triple;
   std::optional<std::string> ObjectFormat;
@@ -94,6 +126,8 @@ struct IFSStub {
   IFSTarget Target;
   std::vector<std::string> NeededLibs;
   std::vector<IFSSymbol> Symbols;
+  std::vector<IFSVerDef> VersionDefinitions;
+  std::vector<IFSVerNeed> VersionRequirements;
 
   IFSStub() = default;
   LLVM_ABI IFSStub(const IFSStub &Stub);