From 25ceb5f3171b24459e86adf5e18cebaaabe247d3 Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Mon, 8 Feb 2010 22:09:08 +0000
Subject: [PATCH] add an x86 implementation of MCTargetExpr for representing
 @GOT and friends.  Use it for personality references as a first use.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95588 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/X86/CMakeLists.txt          |  1 +
 lib/Target/X86/X86MCTargetExpr.cpp     | 43 ++++++++++++++++++++++++++
 lib/Target/X86/X86MCTargetExpr.h       | 42 +++++++++++++++++++++++++
 lib/Target/X86/X86TargetObjectFile.cpp |  6 ++--
 test/CodeGen/X86/personality.ll        |  2 +-
 5 files changed, 90 insertions(+), 4 deletions(-)
 create mode 100644 lib/Target/X86/X86MCTargetExpr.cpp
 create mode 100644 lib/Target/X86/X86MCTargetExpr.h

diff --git a/lib/Target/X86/CMakeLists.txt b/lib/Target/X86/CMakeLists.txt
index 8f4ff1701ed..61f26a73933 100644
--- a/lib/Target/X86/CMakeLists.txt
+++ b/lib/Target/X86/CMakeLists.txt
@@ -26,6 +26,7 @@ set(sources
   X86JITInfo.cpp
   X86MCAsmInfo.cpp
   X86MCCodeEmitter.cpp 
+  X86MCTargetExpr.cpp
   X86RegisterInfo.cpp
   X86Subtarget.cpp
   X86TargetMachine.cpp
diff --git a/lib/Target/X86/X86MCTargetExpr.cpp b/lib/Target/X86/X86MCTargetExpr.cpp
new file mode 100644
index 00000000000..1b0d75a0b5a
--- /dev/null
+++ b/lib/Target/X86/X86MCTargetExpr.cpp
@@ -0,0 +1,43 @@
+//===- X86MCTargetExpr.cpp - X86 Target Specific MCExpr Implementation ----===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "X86MCTargetExpr.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCSymbol.h"
+#include "llvm/MC/MCValue.h"
+#include "llvm/Support/raw_ostream.h"
+using namespace llvm;
+
+X86MCTargetExpr *X86MCTargetExpr::Create(const MCSymbol *Sym, VariantKind K,
+                                         MCContext &Ctx) {
+  return new (Ctx) X86MCTargetExpr(Sym, K);
+}
+
+void X86MCTargetExpr::PrintImpl(raw_ostream &OS) const {
+  OS << *Sym;
+  
+  switch (Kind) {
+  case GOT: OS << "@GOT"; break;
+  case PLT: OS << "@PLT"; break;
+  case GOTPCREL: OS << "@GOTPCREL"; break;
+  }
+}
+
+bool X86MCTargetExpr::EvaluateAsRelocatableImpl(MCValue &Res) const {
+  // FIXME: I don't know if this is right, it followed MCSymbolRefExpr.
+  
+  // Evaluate recursively if this is a variable.
+  if (Sym->isVariable())
+    return Sym->getValue()->EvaluateAsRelocatable(Res);
+  
+  Res = MCValue::get(Sym, 0, 0);
+  return true;
+}
+
+X86MCTargetExpr *foo(MCExpr *A) { return (X86MCTargetExpr*)A; }
\ No newline at end of file
diff --git a/lib/Target/X86/X86MCTargetExpr.h b/lib/Target/X86/X86MCTargetExpr.h
new file mode 100644
index 00000000000..b6d22bb690c
--- /dev/null
+++ b/lib/Target/X86/X86MCTargetExpr.h
@@ -0,0 +1,42 @@
+//===- X86MCTargetExpr.h - X86 Target Specific MCExpr -----------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef X86_MCTARGETEXPR_H
+#define X86_MCTARGETEXPR_H
+
+#include "llvm/MC/MCExpr.h"
+
+namespace llvm {
+
+/// X86MCTargetExpr - This class represents symbol variants, like foo@GOT.
+class X86MCTargetExpr : public MCTargetExpr {
+public:
+  enum VariantKind {
+    GOT,
+    PLT,
+    GOTPCREL
+  };
+private:
+  /// Sym - The symbol being referenced.
+  const MCSymbol * const Sym;
+  /// Kind - The modifier.
+  const VariantKind Kind;
+  
+  X86MCTargetExpr(const MCSymbol *S, VariantKind K) : Sym(S), Kind(K) {}
+public:
+  static X86MCTargetExpr *Create(const MCSymbol *Sym, VariantKind K,
+                                 MCContext &Ctx);
+  
+  void PrintImpl(raw_ostream &OS) const;
+  bool EvaluateAsRelocatableImpl(MCValue &Res) const;
+};
+  
+} // end namespace llvm
+
+#endif
diff --git a/lib/Target/X86/X86TargetObjectFile.cpp b/lib/Target/X86/X86TargetObjectFile.cpp
index a8faafd4b58..9b7d5d23881 100644
--- a/lib/Target/X86/X86TargetObjectFile.cpp
+++ b/lib/Target/X86/X86TargetObjectFile.cpp
@@ -8,9 +8,9 @@
 //===----------------------------------------------------------------------===//
 
 #include "X86TargetObjectFile.h"
+#include "X86MCTargetExpr.h"
 #include "llvm/CodeGen/MachineModuleInfoImpls.h"
 #include "llvm/MC/MCContext.h"
-#include "llvm/MC/MCExpr.h"
 #include "llvm/Target/Mangler.h"
 #include "llvm/ADT/SmallString.h"
 using namespace llvm;
@@ -57,9 +57,9 @@ getSymbolForDwarfGlobalReference(const GlobalValue *GV, Mangler *Mang,
   
   SmallString<128> Name;
   Mang->getNameWithPrefix(Name, GV, false);
-  Name += "@GOTPCREL";
+  const MCSymbol *Sym = getContext().CreateSymbol(Name);
   const MCExpr *Res =
-    MCSymbolRefExpr::Create(Name.str(), getContext());
+    X86MCTargetExpr::Create(Sym, X86MCTargetExpr::GOTPCREL, getContext());
   const MCExpr *Four = MCConstantExpr::Create(4, getContext());
   return MCBinaryExpr::CreateAdd(Res, Four, getContext());
 }
diff --git a/test/CodeGen/X86/personality.ll b/test/CodeGen/X86/personality.ll
index 5acf04cc06c..ce57e8fce6f 100644
--- a/test/CodeGen/X86/personality.ll
+++ b/test/CodeGen/X86/personality.ll
@@ -39,7 +39,7 @@ declare void @__gxx_personality_v0()
 declare void @__cxa_end_catch()
 
 ; X64: Leh_frame_common_begin:
-; X64: .long	___gxx_personality_v0@GOTPCREL+4
+; X64: .long	(___gxx_personality_v0@GOTPCREL)+4
 
 ; X32: Leh_frame_common_begin:
 ; X32: .long	L___gxx_personality_v0$non_lazy_ptr-
-- 
2.34.1