From 52b510b4c4f36f58c4aa37a1f835eb95e89e0adb Mon Sep 17 00:00:00 2001
From: Evan Cheng <evan.cheng@apple.com>
Date: Fri, 23 Jun 2006 01:02:37 +0000
Subject: [PATCH] Added jump table address relocation.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28908 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/llvm/CodeGen/MachineRelocation.h | 39 +++++++++++++++++++++---
 lib/ExecutionEngine/JIT/JITEmitter.cpp   |  6 +++-
 2 files changed, 40 insertions(+), 5 deletions(-)

diff --git a/include/llvm/CodeGen/MachineRelocation.h b/include/llvm/CodeGen/MachineRelocation.h
index c23b999e2ec..58b4f87bc53 100644
--- a/include/llvm/CodeGen/MachineRelocation.h
+++ b/include/llvm/CodeGen/MachineRelocation.h
@@ -39,7 +39,8 @@ class MachineRelocation {
     isResult,         // Relocation has be transformed into its result pointer.
     isGV,             // The Target.GV field is valid.
     isExtSym,         // The Target.ExtSym field is valid.
-    isConstPool,      // The Target.ConstPool field is valid.
+    isConstPool,      // Relocation of constant pool address.
+    isJumpTable,      // Relocation of jump table address.
     isGOTIndex        // The Target.GOTIndex field is valid.
   };
   
@@ -54,7 +55,7 @@ class MachineRelocation {
     void *Result;        // If this has been resolved to a resolved pointer
     GlobalValue *GV;     // If this is a pointer to an LLVM global
     const char *ExtSym;  // If this is a pointer to a named symbol
-    unsigned ConstPool;  // In this is a pointer to a constant pool entry
+    unsigned Index;      // Constant pool / jump table index
     unsigned GOTIndex;   // Index in the GOT of this symbol/global
   } Target;
 
@@ -113,7 +114,24 @@ public:
     Result.AddrType = isConstPool;
     Result.DoesntNeedFnStub = false;
     Result.GOTRelative = false;
-    Result.Target.ConstPool = CPI;
+    Result.Target.Index = CPI;
+    return Result;
+  }
+
+  /// MachineRelocation::getJumpTable - Return a relocation entry for a jump
+  /// table entry.
+  ///
+  static MachineRelocation getJumpTable(intptr_t offset,unsigned RelocationType,
+                                        unsigned JTI, intptr_t cst = 0) {
+    assert((RelocationType & ~63) == 0 && "Relocation type too large!");
+    MachineRelocation Result;
+    Result.Offset = offset;
+    Result.ConstantVal = cst;
+    Result.TargetReloType = RelocationType;
+    Result.AddrType = isJumpTable;
+    Result.DoesntNeedFnStub = false;
+    Result.GOTRelative = false;
+    Result.Target.Index = JTI;
     return Result;
   }
 
@@ -154,6 +172,12 @@ public:
     return AddrType == isConstPool;
   }
 
+  /// isJumpTableIndex - Return true if this is a jump table reference.
+  ///
+  bool isJumpTableIndex() const {
+    return AddrType == isJumpTable;
+  }
+
   /// isGOTRelative - Return true the target wants the index into the GOT of
   /// the symbol rather than the address of the symbol.
   bool isGOTRelative() const {
@@ -187,7 +211,14 @@ public:
   /// the index into the constant pool.
   unsigned getConstantPoolIndex() const {
     assert(isConstantPoolIndex() && "This is not a constant pool reference!");
-    return Target.ConstPool;
+    return Target.Index;
+  }
+
+  /// getJumpTableIndex - If this is a jump table reference, return
+  /// the index into the jump table.
+  unsigned getJumpTableIndex() const {
+    assert(isJumpTableIndex() && "This is not a jump table reference!");
+    return Target.Index;
   }
 
   /// getResultPointer - Once this has been resolved to point to an actual
diff --git a/lib/ExecutionEngine/JIT/JITEmitter.cpp b/lib/ExecutionEngine/JIT/JITEmitter.cpp
index 4300b177379..ef9e43a44f7 100644
--- a/lib/ExecutionEngine/JIT/JITEmitter.cpp
+++ b/lib/ExecutionEngine/JIT/JITEmitter.cpp
@@ -786,9 +786,13 @@ bool JITEmitter::finishFunction(MachineFunction &F) {
         ResultPtr = getPointerToGlobal(MR.getGlobalValue(),
                                        BufferBegin+MR.getMachineCodeOffset(),
                                        MR.doesntNeedFunctionStub());
-      } else {
+      } else if (MR.isConstantPoolIndex()){
         assert(MR.isConstantPoolIndex());
         ResultPtr=(void*)getConstantPoolEntryAddress(MR.getConstantPoolIndex());
+      } else {
+        assert(MR.isJumpTableIndex());
+        ResultPtr=(void*)getJumpTableEntryAddress(MR.getJumpTableIndex());
+
       }
 
       MR.setResultPointer(ResultPtr);