make doxygen comment much better. Patch by B. Scott Michel!

[oota-llvm.git] / include / llvm / Target / TargetJITInfo.h

diff --git a/include/llvm/Target/TargetJITInfo.h b/include/llvm/Target/TargetJITInfo.h
index 90fea4e3c31b086f8e8f382830872c3e9a17aba1..b80b0558f1e1b676683c20f0c62d6a52194e632e 100644 (file)
--- a/include/llvm/Target/TargetJITInfo.h
+++ b/include/llvm/Target/TargetJITInfo.h
@@ -1,10 +1,10 @@
 //===- Target/TargetJITInfo.h - Target Information for JIT ------*- C++ -*-===//
-// 
+//
 //                     The LLVM Compiler Infrastructure
 //
 // This file was developed by the LLVM research group and is distributed under
 // the University of Illinois Open Source License. See LICENSE.TXT for details.
-// 
+//
 //===----------------------------------------------------------------------===//
 //
 // This file exposes an abstract interface used by the Just-In-Time code
@@ -17,37 +17,73 @@
 #ifndef LLVM_TARGET_TARGETJITINFO_H
 #define LLVM_TARGET_TARGETJITINFO_H
 
+#include <cassert>
+#include <vector>
+
 namespace llvm {
   class Function;
   class FunctionPassManager;
+  class MachineBasicBlock;
   class MachineCodeEmitter;
+  class MachineRelocation;
 
   /// TargetJITInfo - Target specific information required by the Just-In-Time
   /// code generator.
-  struct TargetJITInfo {
+  class TargetJITInfo {
+  public:
     virtual ~TargetJITInfo() {}
-    
-    /// addPassesToJITCompile - Add passes to the specified pass manager to
-    /// implement a fast code generator for this target.
-    ///
-    virtual void addPassesToJITCompile(FunctionPassManager &PM) = 0;
-    
+
     /// replaceMachineCodeForFunction - Make it so that calling the function
     /// whose machine code is at OLD turns into a call to NEW, perhaps by
     /// overwriting OLD with a branch to NEW.  This is used for self-modifying
     /// code.
     ///
-    virtual void replaceMachineCodeForFunction (void *Old, void *New) = 0;
-    
-    /// getJITStubForFunction - Create or return a stub for the specified
-    /// function.  This stub acts just like the specified function, except that
-    /// it allows the "address" of the function to be taken without having to
-    /// generate code for it.  Targets do not need to implement this method, but
-    /// doing so will allow for faster startup of the JIT.
-    ///
-    virtual void *getJITStubForFunction(Function *F, MachineCodeEmitter &MCE) {
+    virtual void replaceMachineCodeForFunction(void *Old, void *New) = 0;
+
+    /// emitFunctionStub - Use the specified MachineCodeEmitter object to emit a
+    /// small native function that simply calls the function at the specified
+    /// address.  Return the address of the resultant function.
+    virtual void *emitFunctionStub(void *Fn, MachineCodeEmitter &MCE) {
+      assert(0 && "This target doesn't implement emitFunctionStub!");
+      return 0;
+    }
+
+    /// LazyResolverFn - This typedef is used to represent the function that
+    /// unresolved call points should invoke.  This is a target specific
+    /// function that knows how to walk the stack and find out which stub the
+    /// call is coming from.
+    typedef void (*LazyResolverFn)();
+
+    /// JITCompilerFn - This typedef is used to represent the JIT function that
+    /// lazily compiles the function corresponding to a stub.  The JIT keeps
+    /// track of the mapping between stubs and LLVM Functions, the target
+    /// provides the ability to figure out the address of a stub that is called
+    /// by the LazyResolverFn.
+    typedef void* (*JITCompilerFn)(void *);
+
+    /// getLazyResolverFunction - This method is used to initialize the JIT,
+    /// giving the target the function that should be used to compile a
+    /// function, and giving the JIT the target function used to do the lazy
+    /// resolving.
+    virtual LazyResolverFn getLazyResolverFunction(JITCompilerFn) {
+      assert(0 && "Not implemented for this target!");
       return 0;
     }
+
+    /// relocate - Before the JIT can run a block of code that has been emitted,
+    /// it must rewrite the code to contain the actual addresses of any
+    /// referenced global symbols.
+    virtual void relocate(void *Function, MachineRelocation *MR,
+                          unsigned NumRelocs, unsigned char* GOTBase) {
+      assert(NumRelocs == 0 && "This target does not have relocations!");
+    }
+
+    /// needsGOT - Allows a target to specify that it would like the
+    // JIT to manage a GOT for it.
+    bool needsGOT() const { return useGOT; }
+
+  protected:
+    bool useGOT;
   };
 } // End llvm namespace