Fix batch of converting RegisterPass<> to INTIALIZE_PASS().

[oota-llvm.git] / lib / Transforms / Scalar / LoopUnrollPass.cpp

diff --git a/lib/Transforms/Scalar/LoopUnrollPass.cpp b/lib/Transforms/Scalar/LoopUnrollPass.cpp
index 837ec59dbbce70e6443b78d409329f1268a2d777..1b4583d0b355fe5e3a06b48cb885be9bd8d44b93 100644 (file)
--- a/lib/Transforms/Scalar/LoopUnrollPass.cpp
+++ b/lib/Transforms/Scalar/LoopUnrollPass.cpp
@@ -15,8 +15,8 @@
 #define DEBUG_TYPE "loop-unroll"
 #include "llvm/IntrinsicInst.h"
 #include "llvm/Transforms/Scalar.h"
-#include "llvm/Analysis/LoopInfo.h"
 #include "llvm/Analysis/LoopPass.h"
+#include "llvm/Analysis/InlineCost.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/raw_ostream.h"
@@ -71,51 +71,25 @@ namespace {
 }
 
 char LoopUnroll::ID = 0;
-static RegisterPass<LoopUnroll> X("loop-unroll", "Unroll loops");
+INITIALIZE_PASS(LoopUnroll, "loop-unroll", "Unroll loops", false, false);
 
 Pass *llvm::createLoopUnrollPass() { return new LoopUnroll(); }
 
 /// ApproximateLoopSize - Approximate the size of the loop.
-static unsigned ApproximateLoopSize(const Loop *L) {
-  unsigned Size = 0;
+static unsigned ApproximateLoopSize(const Loop *L, unsigned &NumCalls) {
+  CodeMetrics Metrics;
   for (Loop::block_iterator I = L->block_begin(), E = L->block_end();
-       I != E; ++I) {
-    BasicBlock *BB = *I;
-    Instruction *Term = BB->getTerminator();
-    for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I) {
-      if (isa<PHINode>(I) && BB == L->getHeader()) {
-        // Ignore PHI nodes in the header.
-      } else if (I->hasOneUse() && I->use_back() == Term) {
-        // Ignore instructions only used by the loop terminator.
-      } else if (isa<DbgInfoIntrinsic>(I)) {
-        // Ignore debug instructions
-      } else if (isa<GetElementPtrInst>(I) && I->hasOneUse()) {
-        // Ignore GEP as they generally are subsumed into a load or store.
-      } else if (isa<CallInst>(I)) {
-        // Estimate size overhead introduced by call instructions which
-        // is higher than other instructions. Here 3 and 10 are magic
-        // numbers that help one isolated test case from PR2067 without
-        // negatively impacting measured benchmarks.
-        Size += isa<IntrinsicInst>(I) ? 3 : 10;
-      } else {
-        ++Size;
-      }
-
-      // TODO: Ignore expressions derived from PHI and constants if inval of phi
-      // is a constant, or if operation is associative.  This will get induction
-      // variables.
-    }
-  }
-
-  return Size;
+       I != E; ++I)
+    Metrics.analyzeBasicBlock(*I);
+  NumCalls = Metrics.NumCalls;
+  return Metrics.NumInsts;
 }
 
 bool LoopUnroll::runOnLoop(Loop *L, LPPassManager &LPM) {
-  assert(L->isLCSSAForm());
   LoopInfo *LI = &getAnalysis<LoopInfo>();
 
   BasicBlock *Header = L->getHeader();
-  DEBUG(errs() << "Loop Unroll: F[" << Header->getParent()->getName()
+  DEBUG(dbgs() << "Loop Unroll: F[" << Header->getParent()->getName()
         << "] Loop %" << Header->getName() << "\n");
   (void)Header;
 
@@ -136,14 +110,19 @@ bool LoopUnroll::runOnLoop(Loop *L, LPPassManager &LPM) {
 
   // Enforce the threshold.
   if (UnrollThreshold != NoThreshold) {
-    unsigned LoopSize = ApproximateLoopSize(L);
-    DEBUG(errs() << "  Loop Size = " << LoopSize << "\n");
+    unsigned NumCalls;
+    unsigned LoopSize = ApproximateLoopSize(L, NumCalls);
+    DEBUG(dbgs() << "  Loop Size = " << LoopSize << "\n");
+    if (NumCalls != 0) {
+      DEBUG(dbgs() << "  Not unrolling loop with function calls.\n");
+      return false;
+    }
     uint64_t Size = (uint64_t)LoopSize*Count;
     if (TripCount != 1 && Size > UnrollThreshold) {
-      DEBUG(errs() << "  Too large to fully unroll with count: " << Count
+      DEBUG(dbgs() << "  Too large to fully unroll with count: " << Count
             << " because size: " << Size << ">" << UnrollThreshold << "\n");
       if (!UnrollAllowPartial) {
-        DEBUG(errs() << "  will not try to unroll partially because "
+        DEBUG(dbgs() << "  will not try to unroll partially because "
               << "-unroll-allow-partial not given\n");
         return false;
       }
@@ -153,10 +132,10 @@ bool LoopUnroll::runOnLoop(Loop *L, LPPassManager &LPM) {
         Count--;
       }
       if (Count < 2) {
-        DEBUG(errs() << "  could not unroll partially\n");
+        DEBUG(dbgs() << "  could not unroll partially\n");
         return false;
       }
-      DEBUG(errs() << "  partially unrolling with count: " << Count << "\n");
+      DEBUG(dbgs() << "  partially unrolling with count: " << Count << "\n");
     }
   }