From 6a80f9da8c2cb2cbf931ec8cf2a72b5f288c1bc6 Mon Sep 17 00:00:00 2001
From: Benjamin Kramer <benny.kra@googlemail.com>
Date: Sat, 12 May 2012 14:30:47 +0000
Subject: [PATCH] ELF: Add support for the asm .version directive.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156712 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/MC/MCParser/ELFAsmParser.cpp | 28 ++++++++++++++++++++++++++++
 test/MC/ELF/version.s            | 17 +++++++++++++++++
 2 files changed, 45 insertions(+)
 create mode 100644 test/MC/ELF/version.s

diff --git a/lib/MC/MCParser/ELFAsmParser.cpp b/lib/MC/MCParser/ELFAsmParser.cpp
index ffc400b203f..9316bb1c1cd 100644
--- a/lib/MC/MCParser/ELFAsmParser.cpp
+++ b/lib/MC/MCParser/ELFAsmParser.cpp
@@ -64,6 +64,7 @@ public:
     AddDirectiveHandler<&ELFAsmParser::ParseDirectiveType>(".type");
     AddDirectiveHandler<&ELFAsmParser::ParseDirectiveIdent>(".ident");
     AddDirectiveHandler<&ELFAsmParser::ParseDirectiveSymver>(".symver");
+    AddDirectiveHandler<&ELFAsmParser::ParseDirectiveVersion>(".version");
     AddDirectiveHandler<&ELFAsmParser::ParseDirectiveWeakref>(".weakref");
     AddDirectiveHandler<&ELFAsmParser::ParseDirectiveSymbolAttribute>(".weak");
     AddDirectiveHandler<&ELFAsmParser::ParseDirectiveSymbolAttribute>(".local");
@@ -141,6 +142,7 @@ public:
   bool ParseDirectiveType(StringRef, SMLoc);
   bool ParseDirectiveIdent(StringRef, SMLoc);
   bool ParseDirectiveSymver(StringRef, SMLoc);
+  bool ParseDirectiveVersion(StringRef, SMLoc);
   bool ParseDirectiveWeakref(StringRef, SMLoc);
   bool ParseDirectiveSymbolAttribute(StringRef, SMLoc);
 
@@ -548,6 +550,32 @@ bool ELFAsmParser::ParseDirectiveSymver(StringRef, SMLoc) {
   return false;
 }
 
+/// ParseDirectiveVersion
+///  ::= .version string
+bool ELFAsmParser::ParseDirectiveVersion(StringRef, SMLoc) {
+  if (getLexer().isNot(AsmToken::String))
+    return TokError("unexpected token in '.version' directive");
+
+  StringRef Data = getTok().getIdentifier();
+
+  Lex();
+
+  const MCSection *Note =
+    getContext().getELFSection(".note", ELF::SHT_NOTE, 0,
+                               SectionKind::getReadOnly());
+
+  getStreamer().PushSection();
+  getStreamer().SwitchSection(Note);
+  getStreamer().EmitIntValue(Data.size()+1, 4); // namesz.
+  getStreamer().EmitIntValue(0, 4);             // descsz = 0 (no description).
+  getStreamer().EmitIntValue(1, 4);             // type = NT_VERSION.
+  getStreamer().EmitBytes(Data, 0);             // name.
+  getStreamer().EmitIntValue(0, 1);             // terminate the string.
+  getStreamer().EmitValueToAlignment(4);        // ensure 4 byte alignment.
+  getStreamer().PopSection();
+  return false;
+}
+
 /// ParseDirectiveWeakref
 ///  ::= .weakref foo, bar
 bool ELFAsmParser::ParseDirectiveWeakref(StringRef, SMLoc) {
diff --git a/test/MC/ELF/version.s b/test/MC/ELF/version.s
new file mode 100644
index 00000000000..31e952afeb4
--- /dev/null
+++ b/test/MC/ELF/version.s
@@ -0,0 +1,17 @@
+// RUN: llvm-mc -filetype=obj -triple i386-pc-linux-gnu %s -o - | elf-dump --dump-section-data | FileCheck  %s
+
+.version "1234"
+.version "123"
+
+// CHECK:       (('sh_name', 0x0000000c) # '.note'
+// CHECK-NEXT:   ('sh_type', 0x00000007)
+// CHECK-NEXT:   ('sh_flags', 0x00000000)
+// CHECK-NEXT:   ('sh_addr', 0x00000000)
+// CHECK-NEXT:   ('sh_offset', 0x00000034)
+// CHECK-NEXT:   ('sh_size', 0x00000024)
+// CHECK-NEXT:   ('sh_link', 0x00000000)
+// CHECK-NEXT:   ('sh_info', 0x00000000)
+// CHECK-NEXT:   ('sh_addralign', 0x00000004)
+// CHECK-NEXT:   ('sh_entsize', 0x00000000)
+// CHECK-NEXT:   ('_section_data', '05000000 00000000 01000000 31323334 00000000 04000000 00000000 01000000 31323300')
+// CHECK-NEXT:  ),