[llvm-commits] CVS: llvm/lib/Reoptimizer/LightWtProfiling/Trigger/SecondTrigger.cpp

[Brian Gaeke]

Changes in directory llvm/lib/Reoptimizer/LightWtProfiling/Trigger:

SecondTrigger.cpp updated: 1.7 -> 1.8

---
Log message:

Include scheduler.h to get its prototype(s).
Give triggerBB and printBinary each a comment.
Remove excess parameters that shadow globals from triggerBB.
Replace uses of various `uint64_t one = 1' variables with constant 1ULL.
Refactor find-first-bit-set in 64-bit int into a separate function.


---
Diffs of the changes:

Index: llvm/lib/Reoptimizer/LightWtProfiling/Trigger/SecondTrigger.cpp
diff -u llvm/lib/Reoptimizer/LightWtProfiling/Trigger/SecondTrigger.cpp:1.7 llvm/lib/Reoptimizer/LightWtProfiling/Trigger/SecondTrigger.cpp:1.8
--- llvm/lib/Reoptimizer/LightWtProfiling/Trigger/SecondTrigger.cpp:1.7	Wed Aug  6 16:52:05 2003
+++ llvm/lib/Reoptimizer/LightWtProfiling/Trigger/SecondTrigger.cpp	Thu Aug  7 13:11:44 2003
@@ -10,6 +10,7 @@
 
 #include "GetTimer.h"
 #include "RegSaveRestore.h"
+#include "scheduler.h"
 #include "Timer.h"
 #include "llvm/Reoptimizer/Mapping/LLVMinfo.h"
 #include "llvm/Reoptimizer/VirtualMem.h"
@@ -49,8 +50,6 @@
 
 extern "C" void llvm_first_trigger(int *cnt);
 
-void insert_address_at(uint64_t n, uint64_t m);
-
 // Forward declarations
 void generateTraces(uint64_t start, uint64_t end, 
 		    std::vector<uint64_t> &paths, 
@@ -62,8 +61,12 @@
 std::map<uint64_t, uint64_t> firstTriggerAddr; //tracestart addr
 std::map<uint64_t, pair<long, long> > backOffCounters;
 
-void triggerBB(vector<BasicBlock *> &vBB, VirtualMem *vm, TraceCache *tr, 
-	       TraceCache *tr2, uint64_t a) {
+/// This method is called when we have finally constructed a
+/// trace. The first parameter is the vector of basic blocks that form
+/// the trace; the second parameter is presumably one of the starting
+/// addresses for the trace.
+///
+void triggerBB(vector<BasicBlock *> &vBB, uint64_t a) {
   std::cerr << "We made it to triggerBB\n";
 }
 
@@ -173,17 +176,16 @@
   
   for(int i=0, e = paths.size(); i<e; i++){
     int j;
-    uint64_t one = 1;
     uint64_t temp = paths[i];
     for(j=63; j>-1; j--){
-      if(temp & (one<<j))
+      if(temp & (1ULL << j))
 	break;
     }
     
     //reverse paths
     uint64_t fin = 0;
     for(int x = 0; x<j; x++)
-      fin |= ((((one<<(j-x-1))&temp)>>(j-x-1))<<(x));
+      fin |= ((((1ULL << (j-x-1))&temp)>>(j-x-1))<<(x));
     
     //std::cerr<<"Fin: "<<(void *)fin<<"\n";
     paths[i] = fin;
@@ -392,19 +394,28 @@
                        std::map<int, uint64_t> &targetMap, 
                        std::map<int, uint64_t> &callMap);
 
+/// Find first set bit in the 64-bit number n. This should probably be
+/// reworked to use libc's ffs(3), but note that the return values are
+/// off by one and ffs() takes 32-bit ints.
+///
+int firstBitSet (const uint64_t n) {
+  int x = 0;
+  for(x = 0; x<64; x++)
+    if(n & (1ULL << x))
+      break;
+  return x;
+}
+
 void getIndexToStart(std::pair<int,int> &prtoret, int pathNumber, 
                      std::vector<uint64_t> &paths ){
-  
   int toRet = 0;
   int pathChosen = 0;
-  uint64_t one = 1;
 
   for(int i=0; i<pathNumber; i++){
     uint64_t temp = (paths[pathNumber]^paths[i]);
-    int x=0;
-    for(x=0; x<64; x++)
-      if(temp & (one<<x))
-        break;
+    // Let x be the number of the first bit set in temp, starting with
+    // 0 on the right.
+    int x = firstBitSet (temp);
     if(x>toRet){
       toRet = x;
       pathChosen = i;
@@ -429,13 +440,9 @@
 
 int getIndexToStart(int pathNumber, std::vector<uint64_t> &paths ){
   int toRet = 0;
-  uint64_t one = 1;
   for(int i=0; i<pathNumber; i++){
     uint64_t temp = (paths[pathNumber]^paths[i]);
-    int x=0;
-    for(x=0; x<64; x++)
-      if(temp & (one<<x))
-        break;
+    int x = firstBitSet (temp);
     if(x>toRet)
       toRet = x;
   }
@@ -443,10 +450,12 @@
   return toRet;
 }
 
+/// Print the least-significant 32 bits of the number N, in binary, to
+/// std::cerr, followed by a newline.
+///
 void printBinary(uint64_t n){
-  uint64_t one = 1;
   for(int i=31; i>=0; i--)
-    std::cerr<<((n&(one<<i))>>i);
+    std::cerr<<((n&(1ULL <<i))>>i);
   std::cerr<<"\n";
 }
 
@@ -498,7 +507,7 @@
     }
   }
   
-  triggerBB(vBB, vm, tr, tr2, firstLevelTraceStartAddr);
+  triggerBB(vBB, firstLevelTraceStartAddr);
 } 
 #endif
 
@@ -528,8 +537,6 @@
   std::cerr<<"-----------\n";
 #endif
   
-  uint64_t one = 1; //the constant 1
-
   //branch map and call map
   //map of call instructions
   std::map<int, uint64_t> callMap;
@@ -784,7 +791,7 @@
           nextTrace = (*myIntersections)[pathIndex];
 
         //is it taken?
-        if(firstPath & (one<<pathIndex)){
+        if(firstPath & (1ULL << pathIndex)){
 
 #ifdef FOR_DEBUG
           std::cerr<<" taken \t";