[llvm-commits] CVS: llvm/include/llvm/LinkTimeOptimizer.h

[Devang Patel]

Changes in directory llvm/include/llvm:

LinkTimeOptimizer.h added (r1.1)
---
Log message:

Add new tool, lto, to do link time optimization. This tool installs
dynamic library that linker can use to optimize llvm byte codes at
link time.


---
Diffs of the changes:  (+99 -0)

 LinkTimeOptimizer.h |   99 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 99 insertions(+)


Index: llvm/include/llvm/LinkTimeOptimizer.h
diff -c /dev/null llvm/include/llvm/LinkTimeOptimizer.h:1.1
*** /dev/null	Thu Aug  3 10:45:07 2006
--- llvm/include/llvm/LinkTimeOptimizer.h	Thu Aug  3 10:44:57 2006
***************
*** 0 ****
--- 1,99 ----
+ //===-- llvm/LinkTimeOptimizer.h - Public Interface  ------------*- C++ -*-===//
+ //
+ //                     The LLVM Compiler Infrastructure
+ //
+ // This file was developed by Devang Patel and is distributed under
+ // the University of Illinois Open Source License. See LICENSE.TXT for details.
+ // 
+ //===----------------------------------------------------------------------===//
+ //
+ // This header provides public interface to use LLVM link time optimization
+ // library. This is intended to be used by linker to do link time optimization.
+ //
+ //===----------------------------------------------------------------------===//
+ 
+ #ifndef __LTO_H__
+ #define __LTO_H__
+ 
+ #include <string>
+ #include <vector>
+ #include <set>
+ #include <llvm/ADT/hash_map>
+ 
+ namespace llvm {
+ 
+   class Module;
+   class GlobalValue;
+ 
+   enum LTOStatus {
+     LTO_UNKNOWN,
+     LTO_OPT_SUCCESS,
+     LTO_READ_SUCCESS,
+     LTO_READ_FAILURE,
+     LTO_WRITE_FAILURE,
+     LTO_NO_TARGET,
+     LTO_NO_WORK,
+     LTO_MODULE_MERGE_FAILURE,
+     LTO_ASM_FAILURE
+   };
+  
+   enum LTOLinkageTypes {
+     LTOExternalLinkage, // Externally visible function
+     LTOLinkOnceLinkage, // Keep one copy of named function when linking (inline)
+     LTOWeakLinkage,     // Keep one copy of named function when linking (weak)
+     LTOInternalLinkage  // Rename collisions when linking (static functions)
+   };
+ 
+   /// This class representes LLVM symbol information without exposing details
+   /// of LLVM global values. It encapsulates symbol linkage information. This
+   /// is typically used in hash_map where associated name identifies the 
+   /// the symbol name.
+   class LLVMSymbol {
+ 
+   public:
+ 
+     LTOLinkageTypes getLinkage() const { return linkage; }
+     void mayBeNotUsed();
+ 
+   LLVMSymbol (enum LTOLinkageTypes lt, GlobalValue *g) : linkage(lt), gv(g) {}
+ 
+   private:
+     enum LTOLinkageTypes linkage;
+     GlobalValue *gv;
+   };
+ 
+   class string_compare {
+   public:
+     bool operator()(const char* left, const char* right) const { 
+       return (strcmp(left, right) == 0); 
+     }
+   };
+   
+   /// This is the main link time optimization class. It exposes simple API
+   /// to perform link time optimization using LLVM intermodular optimizer.
+   class LinkTimeOptimizer {
+ 
+   public:
+     typedef hash_map<const char*, LLVMSymbol*, hash<const char*>, 
+ 		     string_compare> NameToSymbolMap;
+ 
+     enum LTOStatus readLLVMObjectFile(const std::string &InputFilename,
+ 				      NameToSymbolMap &symbols,
+ 				      std::set<const char*> &references);
+     enum LTOStatus optimizeModules(const std::string &OutputFilename,
+ 				   std::vector<const char*> &exportList);
+ 
+   private:
+     std::vector<Module *> modules;
+     NameToSymbolMap allSymbols;
+   };
+ 
+ } // End llvm namespace
+ 
+ /// This provides C interface to initialize link time optimizer. This allows
+ /// linker to use dlopen() interface to dynamically load LinkTimeOptimizer.
+ /// extern "C" helps, because dlopen() interface uses name to find the symbol.
+ extern "C"
+ llvm::LinkTimeOptimizer *createLLVMOptimizer();
+ 
+ #endif