X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FCodeGen%2FMachineJumpTableInfo.h;h=928145d279b6bc6848f0494df44fc3d3de87dcd6;hb=53e98a2c4aa7065f4136c5263b14192036c1e056;hp=c0f4af34c226b4845e6996a051aba334518c59d5;hpb=a69571c7991813c93cba64e88eced6899ce93d81;p=oota-llvm.git

diff --git a/include/llvm/CodeGen/MachineJumpTableInfo.h b/include/llvm/CodeGen/MachineJumpTableInfo.h
index c0f4af34c22..928145d279b 100644
--- a/include/llvm/CodeGen/MachineJumpTableInfo.h
+++ b/include/llvm/CodeGen/MachineJumpTableInfo.h
@@ -2,17 +2,17 @@
 //
 //                     The LLVM Compiler Infrastructure
 //
-// This file was developed by Nate Begeman and is distributed under the
-// University of Illinois Open Source License. See LICENSE.TXT for details.
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // The MachineJumpTableInfo class keeps track of jump tables referenced by
 // lowered switch instructions in the MachineFunction.
 //
-// Instructions reference the address of these jump tables through the use of 
-// MO_JumpTableIndex values.  When emitting assembly or machine code, these 
-// virtual address references are converted to refer to the address of the 
+// Instructions reference the address of these jump tables through the use of
+// MO_JumpTableIndex values.  When emitting assembly or machine code, these
+// virtual address references are converted to refer to the address of the
 // function jump tables.
 //
 //===----------------------------------------------------------------------===//
@@ -21,31 +21,77 @@
 #define LLVM_CODEGEN_MACHINEJUMPTABLEINFO_H
 
 #include <vector>
-#include <iosfwd>
+#include <cassert>
 
 namespace llvm {
 
 class MachineBasicBlock;
+class DataLayout;
+class raw_ostream;
 
 /// MachineJumpTableEntry - One jump table in the jump table info.
 ///
 struct MachineJumpTableEntry {
   /// MBBs - The vector of basic blocks from which to create the jump table.
   std::vector<MachineBasicBlock*> MBBs;
-  
-  MachineJumpTableEntry(std::vector<MachineBasicBlock*> &M) : MBBs(M) {}
+
+  explicit MachineJumpTableEntry(const std::vector<MachineBasicBlock*> &M)
+  : MBBs(M) {}
 };
-  
+
 class MachineJumpTableInfo {
-  const TargetData *TD;
+public:
+  /// JTEntryKind - This enum indicates how each entry of the jump table is
+  /// represented and emitted.
+  enum JTEntryKind {
+    /// EK_BlockAddress - Each entry is a plain address of block, e.g.:
+    ///     .word LBB123
+    EK_BlockAddress,
+
+    /// EK_GPRel64BlockAddress - Each entry is an address of block, encoded
+    /// with a relocation as gp-relative, e.g.:
+    ///     .gpdword LBB123
+    EK_GPRel64BlockAddress,
+
+    /// EK_GPRel32BlockAddress - Each entry is an address of block, encoded
+    /// with a relocation as gp-relative, e.g.:
+    ///     .gprel32 LBB123
+    EK_GPRel32BlockAddress,
+
+    /// EK_LabelDifference32 - Each entry is the address of the block minus
+    /// the address of the jump table.  This is used for PIC jump tables where
+    /// gprel32 is not supported.  e.g.:
+    ///      .word LBB123 - LJTI1_2
+    /// If the .set directive is supported, this is emitted as:
+    ///      .set L4_5_set_123, LBB123 - LJTI1_2
+    ///      .word L4_5_set_123
+    EK_LabelDifference32,
+
+    /// EK_Inline - Jump table entries are emitted inline at their point of
+    /// use. It is the responsibility of the target to emit the entries.
+    EK_Inline,
+
+    /// EK_Custom32 - Each entry is a 32-bit value that is custom lowered by the
+    /// TargetLowering::LowerCustomJumpTableEntry hook.
+    EK_Custom32
+  };
+private:
+  JTEntryKind EntryKind;
   std::vector<MachineJumpTableEntry> JumpTables;
 public:
-  MachineJumpTableInfo(const TargetData *td) : TD(td) {}
-    
-  /// getJumpTableIndex - Create a new jump table or return an existing one.
+  explicit MachineJumpTableInfo(JTEntryKind Kind): EntryKind(Kind) {}
+
+  JTEntryKind getEntryKind() const { return EntryKind; }
+
+  /// getEntrySize - Return the size of each entry in the jump table.
+  unsigned getEntrySize(const DataLayout &TD) const;
+  /// getEntryAlignment - Return the alignment of each entry in the jump table.
+  unsigned getEntryAlignment(const DataLayout &TD) const;
+
+  /// createJumpTableIndex - Create a new jump table.
   ///
-  unsigned getJumpTableIndex(std::vector<MachineBasicBlock*> &DestBBs);
-  
+  unsigned createJumpTableIndex(const std::vector<MachineBasicBlock*> &DestBBs);
+
   /// isEmpty - Return true if there are no jump tables.
   ///
   bool isEmpty() const { return JumpTables.empty(); }
@@ -53,19 +99,28 @@ public:
   const std::vector<MachineJumpTableEntry> &getJumpTables() const {
     return JumpTables;
   }
-  
-  /// getEntrySize - returns the size of an individual field in a jump table 
-  unsigned getEntrySize() const;
-  
-  /// getAlignment - returns the target's preferred alignment for jump tables
-  unsigned getAlignment() const;
-  
+
+  /// RemoveJumpTable - Mark the specific index as being dead.  This will
+  /// prevent it from being emitted.
+  void RemoveJumpTable(unsigned Idx) {
+    JumpTables[Idx].MBBs.clear();
+  }
+
+  /// ReplaceMBBInJumpTables - If Old is the target of any jump tables, update
+  /// the jump tables to branch to New instead.
+  bool ReplaceMBBInJumpTables(MachineBasicBlock *Old, MachineBasicBlock *New);
+
+  /// ReplaceMBBInJumpTable - If Old is a target of the jump tables, update
+  /// the jump table to branch to New instead.
+  bool ReplaceMBBInJumpTable(unsigned Idx, MachineBasicBlock *Old,
+                             MachineBasicBlock *New);
+
   /// print - Used by the MachineFunction printer to print information about
   /// jump tables.  Implemented in MachineFunction.cpp
   ///
-  void print(std::ostream &OS) const;
+  void print(raw_ostream &OS) const;
 
-  /// dump - Call print(std::cerr) to be called from the debugger.
+  /// dump - Call to stderr.
   ///
   void dump() const;
 };