[LSV] Use make_range, and reformat a DEBUG message. NFC

Summary:
The DEBUG message was hard to read because two Values were being printed
on the same line with only the delimiter "aliases".  This change makes
us print each Value on its own line.

Reviewers: asbirlea

Subscribers: llvm-commits, arsenm, mzolotukhin

Differential Revision: https://reviews.llvm.org/D22533

llvm-svn: 276055

1 files changed, 15 insertions, 12 deletions

diff --git a/llvm/lib/Transforms/Vectorize/LoadStoreVectorizer.cpp b/llvm/lib/Transforms/Vectorize/LoadStoreVectorizer.cpp
index 941699a005e..290681599c0 100644
--- a/llvm/lib/Transforms/Vectorize/LoadStoreVectorizer.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoadStoreVectorizer.cpp
@@ -431,14 +431,15 @@ unsigned Vectorizer::getVectorizablePrefixEndIdx(ArrayRef<Value *> Chain,
   SmallVector<std::pair<Value *, unsigned>, 16> ChainInstrs;
 
   unsigned InstrIdx = 0;
-  for (auto I = From; I != To; ++I, ++InstrIdx) {
+  for (Instruction &I : make_range(From, To)) {
+    ++InstrIdx;
     if (isa<LoadInst>(I) || isa<StoreInst>(I)) {
-      if (!is_contained(Chain, &*I))
-        MemoryInstrs.push_back({&*I, InstrIdx});
+      if (!is_contained(Chain, &I))
+        MemoryInstrs.push_back({&I, InstrIdx});
       else
-        ChainInstrs.push_back({&*I, InstrIdx});
-    } else if (I->mayHaveSideEffects()) {
-      DEBUG(dbgs() << "LSV: Found side-effecting operation: " << *I << '\n');
+        ChainInstrs.push_back({&I, InstrIdx});
+    } else if (I.mayHaveSideEffects()) {
+      DEBUG(dbgs() << "LSV: Found side-effecting operation: " << I << '\n');
       return 0;
     }
   }
@@ -477,11 +478,13 @@ unsigned Vectorizer::getVectorizablePrefixEndIdx(ArrayRef<Value *> Chain,
           Value *Ptr0 = getPointerOperand(M0);
           Value *Ptr1 = getPointerOperand(M1);
 
-          dbgs() << "LSV: Found alias.\n"
-                    "        Aliasing instruction and pointer:\n"
-                 << *MemInstrValue << " aliases " << *Ptr0 << '\n'
-                 << "        Aliased instruction and pointer:\n"
-                 << *ChainInstrValue << " aliases " << *Ptr1 << '\n';
+          dbgs() << "LSV: Found alias:\n"
+                    "  Aliasing instruction and pointer:\n"
+                 << "  " << *MemInstrValue << '\n'
+                 << "  " << *Ptr0 << '\n'
+                 << "  Aliased instruction and pointer:\n"
+                 << "  " << *ChainInstrValue << '\n'
+                 << "  " << *Ptr1 << '\n';
         });
 
         return ChainIdx;
@@ -744,7 +747,7 @@ bool Vectorizer::vectorizeStoreChain(
   DEBUG({
     dbgs() << "LSV: Stores to vectorize:\n";
     for (Value *V : Chain)
-      V->dump();
+      dbgs() << "  " << *V << "\n";
   });
 
   // We won't try again to vectorize the elements of the chain, regardless of