[llvm-commits] CVS: llvm/include/llvm/CodeGen/FunctionLiveVarInfo.h

Chris Lattner lattner at cs.uiuc.edu
Tue Sep 30 13:06:02 PDT 2003


Changes in directory llvm/include/llvm/CodeGen:

FunctionLiveVarInfo.h updated: 1.28 -> 1.29

---
Log message:

Fix header file comment


---
Diffs of the changes:

Index: llvm/include/llvm/CodeGen/FunctionLiveVarInfo.h
diff -u llvm/include/llvm/CodeGen/FunctionLiveVarInfo.h:1.28 llvm/include/llvm/CodeGen/FunctionLiveVarInfo.h:1.29
--- llvm/include/llvm/CodeGen/FunctionLiveVarInfo.h:1.28	Tue Aug 12 18:39:08 2003
+++ llvm/include/llvm/CodeGen/FunctionLiveVarInfo.h	Tue Sep 30 13:05:30 2003
@@ -1,62 +1,29 @@
-/* Title:   FunctionLiveVarInfo.h             -*- C++ -*-
-   Author:  Ruchira Sasanka
-   Date:    Jun 30, 01
-   Purpose: 
-
-   This is the interface for live variable info of a function that is required 
-   by any other part of the compiler
-
-   It must be called like:
-
-       FunctionLiveVarInfo FLVI(Function *);  // initializes data structures
-       FLVI.analyze();                     // do the actural live variable anal
-
- After the analysis, getInSetOfBB or getOutSetofBB can be called to get 
- live var info of a BB.
-
- The live var set before an instruction can be obtained in 2 ways:
-
- 1. Use the method getLiveVarSetAfterInst(Instruction *) to get the LV Info 
-    just after an instruction. (also exists getLiveVarSetBeforeInst(..))
-
-    This function caluclates the LV info for a BB only once and caches that 
-    info. If the cache does not contain the LV info of the instruction, it 
-    calculates the LV info for the whole BB and caches them.
-
-    Getting liveVar info this way uses more memory since, LV info should be 
-    cached. However, if you need LV info of nearly all the instructions of a
-    BB, this is the best and simplest interfrace.
-
-
- 2. Use the OutSet and applyTranferFuncForInst(const Instruction *const Inst) 
-    declared in LiveVarSet and  traverse the instructions of a basic block in 
-    reverse (using const_reverse_iterator in the BB class). 
-
-    This is the most memory efficient method if you need LV info for 
-    only several instructions in a BasicBlock. An example is given below:
-
-
-    LiveVarSet LVSet;  // this will be the set used to traverse through each BB
-
-    // Initialize LVSet so that it is the same as OutSet of the BB
-    LVSet.setUnion( LVI->getOutSetOfBB( *BBI ) );  
- 
-    BasicBlock::InstListType::const_reverse_iterator 
-      InstIterator = InstListInBB.rbegin(); // get the rev iter for inst in BB
-
-      // iterate over all the instructions in BB in reverse
-    for( ; InstIterator != InstListInBB.rend(); InstIterator++) {  
-
-      //...... all  code here which uses LVSet ........
-
-      LVSet.applyTranferFuncForInst(*InstIterator);
-
-      // Now LVSet contains live vars ABOVE the current instrution
-    }
-
-    See buildInterferenceGraph() for the above example.
-*/
-
+//===-- CodeGen/FunctionLiveVarInfo.h - LiveVar Analysis --------*- C++ -*-===//
+//
+// This is the interface for live variable info of a function that is required 
+// by any other part of the compiler
+//
+// After the analysis, getInSetOfBB or getOutSetofBB can be called to get 
+// live var info of a BB.
+//
+// The live var set before an instruction can be obtained in 2 ways:
+//
+// 1. Use the method getLiveVarSetAfterInst(Instruction *) to get the LV Info 
+//    just after an instruction. (also exists getLiveVarSetBeforeInst(..))
+//
+//    This function caluclates the LV info for a BB only once and caches that 
+//    info. If the cache does not contain the LV info of the instruction, it 
+//    calculates the LV info for the whole BB and caches them.
+//
+//    Getting liveVar info this way uses more memory since, LV info should be 
+//    cached. However, if you need LV info of nearly all the instructions of a
+//    BB, this is the best and simplest interfrace.
+//
+// 2. Use the OutSet and applyTranferFuncForInst(const Instruction *const Inst) 
+//    declared in LiveVarSet and  traverse the instructions of a basic block in 
+//    reverse (using const_reverse_iterator in the BB class). 
+//
+//===----------------------------------------------------------------------===//
 
 #ifndef FUNCTION_LIVE_VAR_INFO_H
 #define FUNCTION_LIVE_VAR_INFO_H





More information about the llvm-commits mailing list