[ScopInfo] Do not use LLVM names to identify statements, arrays, and parameters

LLVM-IR names are commonly available in debug builds, but often not in release
builds. Hence, using LLVM-IR names to identify statements or memory reference
results makes the behavior of Polly depend on the compile mode. This is
undesirable. Hence, we now just number the statements instead of using LLVM-IR
names to identify them (this issue has previously been brought up by Zino
Benaissa).

However, as LLVM-IR names help in making test cases more readable, we add an
option '-polly-use-llvm-names' to still use LLVM-IR names. This flag is by
default set in the polly tests to make test cases more readable.

This change reduces the time in ScopInfo from 32 seconds to 2 seconds for the
following test case provided by Eli Friedman <efriedma@codeaurora.org> (already
used in one of the previous commits):

  struct X { int x; };
  void a();
  #define SIG (int x, X **y, X **z)
  typedef void (*fn)SIG;
  #define FN { for (int i = 0; i < x; ++i) { (*y)[i].x += (*z)[i].x; } a(); }
  #define FN5 FN FN FN FN FN
  #define FN25 FN5 FN5 FN5 FN5
  #define FN125 FN25 FN25 FN25 FN25 FN25
  #define FN250 FN125 FN125
  #define FN1250 FN250 FN250 FN250 FN250 FN250
  void x SIG { FN1250 }

For a larger benchmark I have on-hand (10000 loops), this reduces the time for
running -polly-scops from 5 minutes to 4 minutes, a reduction by 20%.

The reason for this large speedup is that our previous use of printAsOperand
had a quadratic cost, as for each printed and unnamed operand the full function
was scanned to find the instruction number that identifies the operand.

We do not need to adjust the way memory reference ids are constructured, as
they do not use LLVM values.

Reviewed by: efriedma

Tags: #polly

Differential Revision: https://reviews.llvm.org/D32789

llvm-svn: 302072

7 files changed, 411 insertions, 30 deletions

diff --git a/polly/include/polly/ScopInfo.h b/polly/include/polly/ScopInfo.h
index ed45cf70883..5d3f455a507 100644
--- a/polly/include/polly/ScopInfo.h
+++ b/polly/include/polly/ScopInfo.h
@@ -1710,6 +1710,12 @@ private:
   /// List of invariant accesses.
   InvariantEquivClassesTy InvariantEquivClasses;
 
+  /// The smallest array index not yet assigned.
+  long ArrayIdx = 0;
+
+  /// The smallest statement index not yet assigned.
+  long StmtIdx = 0;
+
   /// Scop constructor; invoked from ScopBuilder::buildScop.
   Scop(Region &R, ScalarEvolution &SE, LoopInfo &LI,
        ScopDetection::DetectionContext &DC);
@@ -2620,6 +2626,18 @@ public:
   ///                      When true, also removes statements without
   ///                      side-effects.
   void simplifySCoP(bool AfterHoisting);
+
+  /// Get the next free array index.
+  ///
+  /// This function returns a unique index which can be used to identify an
+  /// array.
+  long getNextArrayIdx() { return ArrayIdx++; }
+
+  /// Get the next free statement index.
+  ///
+  /// This function returns a unique index which can be used to identify a
+  /// statement.
+  long getNextStmtIdx() { return StmtIdx++; }
 };
 
 /// Print Scop scop to raw_ostream O.
diff --git a/polly/include/polly/Support/GICHelper.h b/polly/include/polly/Support/GICHelper.h
index 9ec2614fcd4..2ca6bbba6d1 100644
--- a/polly/include/polly/Support/GICHelper.h
+++ b/polly/include/polly/Support/GICHelper.h
@@ -235,10 +235,43 @@ inline llvm::raw_ostream &operator<<(llvm::raw_ostream &OS,
   return OS;
 }
 
-/// Return @p Prefix + @p Val->getName() + @p Suffix but Isl compatible.
+/// Combine Prefix, Val (or Number) and Suffix to an isl-compatible name.
+///
+/// In case @p UseInstructionNames is set, this function returns:
+///
+/// @p Prefix + "_" + @p Val->getName() + @p Suffix
+///
+/// otherwise
+///
+/// @p Prefix + to_string(Number) + @p Suffix
+///
+/// We ignore the value names by default, as they may change between release
+/// and debug mode and can consequently not be used when aiming for reproducible
+/// builds. However, for debugging named statements are often helpful, hence
+/// we allow their optional use.
 std::string getIslCompatibleName(const std::string &Prefix,
-                                 const llvm::Value *Val,
-                                 const std::string &Suffix);
+                                 const llvm::Value *Val, long Number,
+                                 const std::string &Suffix,
+                                 bool UseInstructionNames);
+
+/// Combine Prefix, Name (or Number) and Suffix to an isl-compatible name.
+///
+/// In case @p UseInstructionNames is set, this function returns:
+///
+/// @p Prefix + "_" + Name + @p Suffix
+///
+/// otherwise
+///
+/// @p Prefix + to_string(Number) + @p Suffix
+///
+/// We ignore @p Name by default, as they may change between release
+/// and debug mode and can consequently not be used when aiming for reproducible
+/// builds. However, for debugging named statements are often helpful, hence
+/// we allow their optional use.
+std::string getIslCompatibleName(const std::string &Prefix,
+                                 const std::string &Middle, long Number,
+                                 const std::string &Suffix,
+                                 bool UseInstructionNames);
 
 std::string getIslCompatibleName(const std::string &Prefix,
                                  const std::string &Middle,
diff --git a/polly/lib/Analysis/ScopInfo.cpp b/polly/lib/Analysis/ScopInfo.cpp
index 9df373b9588..d68f121d96b 100644
--- a/polly/lib/Analysis/ScopInfo.cpp
+++ b/polly/lib/Analysis/ScopInfo.cpp
@@ -158,6 +158,12 @@ static cl::opt<bool> PollyPreciseFoldAccesses(
     cl::desc("Fold memory accesses to model more possible delinearizations "
              "(does not scale well)"),
     cl::Hidden, cl::init(false), cl::cat(PollyCategory));
+
+static cl::opt<bool> UseInstructionNames(
+    "polly-use-llvm-names",
+    cl::desc("Use LLVM-IR names when deriving statement names"), cl::Hidden,
+    cl::init(false), cl::ZeroOrMore, cl::cat(PollyCategory));
+
 //===----------------------------------------------------------------------===//
 
 // Create a sequence of two schedules. Either argument may be null and is
@@ -240,8 +246,9 @@ ScopArrayInfo::ScopArrayInfo(Value *BasePtr, Type *ElementType, isl_ctx *Ctx,
     : BasePtr(BasePtr), ElementType(ElementType), Kind(Kind), DL(DL), S(*S) {
   std::string BasePtrName =
       BaseName ? BaseName
-               : getIslCompatibleName("MemRef_", BasePtr,
-                                      Kind == MemoryKind::PHI ? "__phi" : "");
+               : getIslCompatibleName("MemRef", BasePtr, S->getNextArrayIdx(),
+                                      Kind == MemoryKind::PHI ? "__phi" : "",
+                                      UseInstructionNames);
   Id = isl_id_alloc(Ctx, BasePtrName.c_str(), this);
 
   updateSizes(Sizes);
@@ -1574,14 +1581,16 @@ ScopStmt::ScopStmt(Scop &parent, Region &R, Loop *SurroundingLoop)
     : Parent(parent), InvalidDomain(nullptr), Domain(nullptr), BB(nullptr),
       R(&R), Build(nullptr), SurroundingLoop(SurroundingLoop) {
 
-  BaseName = getIslCompatibleName("Stmt_", R.getNameStr(), "");
+  BaseName = getIslCompatibleName(
+      "Stmt", R.getNameStr(), parent.getNextStmtIdx(), "", UseInstructionNames);
 }
 
 ScopStmt::ScopStmt(Scop &parent, BasicBlock &bb, Loop *SurroundingLoop)
     : Parent(parent), InvalidDomain(nullptr), Domain(nullptr), BB(&bb),
       R(nullptr), Build(nullptr), SurroundingLoop(SurroundingLoop) {
 
-  BaseName = getIslCompatibleName("Stmt_", &bb, "");
+  BaseName = getIslCompatibleName("Stmt", &bb, parent.getNextStmtIdx(), "",
+                                  UseInstructionNames);
 }
 
 ScopStmt::ScopStmt(Scop &parent, __isl_take isl_map *SourceRel,
@@ -1891,25 +1900,27 @@ void Scop::createParameterId(const SCEV *Parameter) {
 
   std::string ParameterName = "p_" + std::to_string(getNumParams() - 1);
 
-  if (const SCEVUnknown *ValueParameter = dyn_cast<SCEVUnknown>(Parameter)) {
-    Value *Val = ValueParameter->getValue();
-
-    // If this parameter references a specific Value and this value has a name
-    // we use this name as it is likely to be unique and more useful than just
-    // a number.
-    if (Val->hasName())
-      ParameterName = Val->getName();
-    else if (LoadInst *LI = dyn_cast<LoadInst>(Val)) {
-      auto *LoadOrigin = LI->getPointerOperand()->stripInBoundsOffsets();
-      if (LoadOrigin->hasName()) {
-        ParameterName += "_loaded_from_";
-        ParameterName +=
-            LI->getPointerOperand()->stripInBoundsOffsets()->getName();
+  if (UseInstructionNames) {
+    if (const SCEVUnknown *ValueParameter = dyn_cast<SCEVUnknown>(Parameter)) {
+      Value *Val = ValueParameter->getValue();
+
+      // If this parameter references a specific Value and this value has a name
+      // we use this name as it is likely to be unique and more useful than just
+      // a number.
+      if (Val->hasName())
+        ParameterName = Val->getName();
+      else if (LoadInst *LI = dyn_cast<LoadInst>(Val)) {
+        auto *LoadOrigin = LI->getPointerOperand()->stripInBoundsOffsets();
+        if (LoadOrigin->hasName()) {
+          ParameterName += "_loaded_from_";
+          ParameterName +=
+              LI->getPointerOperand()->stripInBoundsOffsets()->getName();
+        }
       }
     }
-  }
 
-  ParameterName = getIslCompatibleName("", ParameterName, "");
+    ParameterName = getIslCompatibleName("", ParameterName, "");
+  }
 
   auto *Id = isl_id_alloc(getIslCtx(), ParameterName.c_str(),
                           const_cast<void *>((const void *)Parameter));
diff --git a/polly/lib/Support/GICHelper.cpp b/polly/lib/Support/GICHelper.cpp
index e2e10115ac3..6435fabb171 100644
--- a/polly/lib/Support/GICHelper.cpp
+++ b/polly/lib/Support/GICHelper.cpp
@@ -193,13 +193,32 @@ std::string polly::getIslCompatibleName(const std::string &Prefix,
 }
 
 std::string polly::getIslCompatibleName(const std::string &Prefix,
-                                        const Value *Val,
-                                        const std::string &Suffix) {
+                                        const std::string &Name, long Number,
+                                        const std::string &Suffix,
+                                        bool UseInstructionNames) {
+  std::string S = Prefix;
+
+  if (UseInstructionNames)
+    S += std::string("_") + Name;
+  else
+    S += std::to_string(Number);
+
+  S += Suffix;
+
+  makeIslCompatible(S);
+  return S;
+}
+
+std::string polly::getIslCompatibleName(const std::string &Prefix,
+                                        const Value *Val, long Number,
+                                        const std::string &Suffix,
+                                        bool UseInstructionNames) {
   std::string ValStr;
-  raw_string_ostream OS(ValStr);
-  Val->printAsOperand(OS, false);
-  ValStr = OS.str();
-  // Remove the leading %
-  ValStr.erase(0, 1);
+
+  if (UseInstructionNames && Val->hasName())
+    ValStr = std::string("_") + std::string(Val->getName());
+  else
+    ValStr = std::to_string(Number);
+
   return getIslCompatibleName(Prefix, ValStr, Suffix);
 }
diff --git a/polly/test/ScopInfo/unnamed_nonaffine.ll b/polly/test/ScopInfo/unnamed_nonaffine.ll
new file mode 100644
index 00000000000..4b28ffc711d
--- /dev/null
+++ b/polly/test/ScopInfo/unnamed_nonaffine.ll
@@ -0,0 +1,150 @@
+; RUN: opt %loadPolly -polly-allow-nonaffine -polly-scops -analyze < %s \
+; RUN:     -polly-use-llvm-names=true | FileCheck %s
+;
+; RUN: opt %loadPolly -polly-allow-nonaffine -polly-scops -analyze < %s \
+; RUN:     -polly-use-llvm-names=false | FileCheck %s -check-prefix=UNNAMED
+;
+;    void f(int *A, int b) {
+;      int x;
+;      for (int i = 0; i < 1024; i++) {
+;        if (b > i)
+;          x = 0;
+;        else if (b < 2 * i)
+;          x = 3;
+;        else
+;          x = b;
+;
+;        if (A[x])
+;          A[x] = 0;
+;      }
+;    }
+;
+; CHECK:      Statements {
+; CHECK-NEXT:     Stmt_bb3
+; CHECK-NEXT:         Domain :=
+; CHECK-NEXT:             [b] -> { Stmt_bb3[i0] : 0 <= i0 <= 1023 and i0 < b };
+; CHECK-NEXT:         Schedule :=
+; CHECK-NEXT:             [b] -> { Stmt_bb3[i0] -> [i0, 2] };
+; CHECK-NEXT:         MustWriteAccess :=    [Reduction Type: NONE] [Scalar: 1]
+; CHECK-NEXT:             [b] -> { Stmt_bb3[i0] -> MemRef_x_1__phi[] };
+; CHECK-NEXT:     Stmt_bb7
+; CHECK-NEXT:         Domain :=
+; CHECK-NEXT:             [b] -> { Stmt_bb7[i0] : i0 >= b and 0 <= i0 <= 1023 and 2i0 > b };
+; CHECK-NEXT:         Schedule :=
+; CHECK-NEXT:             [b] -> { Stmt_bb7[i0] -> [i0, 1] };
+; CHECK-NEXT:         MustWriteAccess :=    [Reduction Type: NONE] [Scalar: 1]
+; CHECK-NEXT:             [b] -> { Stmt_bb7[i0] -> MemRef_x_1__phi[] };
+; CHECK-NEXT:     Stmt_bb8
+; CHECK-NEXT:         Domain :=
+; CHECK-NEXT:             [b] -> { Stmt_bb8[0] : b = 0 };
+; CHECK-NEXT:         Schedule :=
+; CHECK-NEXT:             [b] -> { Stmt_bb8[i0] -> [0, 0] };
+; CHECK-NEXT:         MustWriteAccess :=    [Reduction Type: NONE] [Scalar: 1]
+; CHECK-NEXT:             [b] -> { Stmt_bb8[i0] -> MemRef_x_1__phi[] };
+; CHECK-NEXT:     Stmt_bb10__TO__bb18
+; CHECK-NEXT:         Domain :=
+; CHECK-NEXT:             [b] -> { Stmt_bb10__TO__bb18[i0] : 0 <= i0 <= 1023 };
+; CHECK-NEXT:         Schedule :=
+; CHECK-NEXT:             [b] -> { Stmt_bb10__TO__bb18[i0] -> [i0, 3] }
+; CHECK-NEXT:         ReadAccess :=    [Reduction Type: NONE] [Scalar: 1]
+; CHECK-NEXT:             [b] -> { Stmt_bb10__TO__bb18[i0] -> MemRef_x_1__phi[] };
+; CHECK-NEXT:         ReadAccess :=    [Reduction Type: NONE] [Scalar: 0]
+; CHECK-NEXT:             [b] -> { Stmt_bb10__TO__bb18[i0] -> MemRef_A[o0] };
+; CHECK-NEXT:         MayWriteAccess :=    [Reduction Type: NONE] [Scalar: 0]
+; CHECK-NEXT:             [b] -> { Stmt_bb10__TO__bb18[i0] -> MemRef_A[o0] };
+; CHECK-NEXT: }
+
+; UNNAMED:          Arrays {
+; UNNAMED-NEXT:         i32 MemRef0__phi; // Element size 4
+; UNNAMED-NEXT:         i32 MemRef1[*]; // Element size 4
+; UNNAMED-NEXT:     }
+
+; UNNAMED:          Statements {
+; UNNAMED-NEXT:     	Stmt2
+; UNNAMED-NEXT:             Domain :=
+; UNNAMED-NEXT:                 [p_0] -> { Stmt2[i0] : 0 <= i0 <= 1023 and i0 < p_0 };
+; UNNAMED-NEXT:             Schedule :=
+; UNNAMED-NEXT:                 [p_0] -> { Stmt2[i0] -> [i0, 2] };
+; UNNAMED-NEXT:             MustWriteAccess :=	[Reduction Type: NONE] [Scalar: 1]
+; UNNAMED-NEXT:                 [p_0] -> { Stmt2[i0] -> MemRef0__phi[] };
+; UNNAMED-NEXT:     	Stmt4
+; UNNAMED-NEXT:             Domain :=
+; UNNAMED-NEXT:                 [p_0] -> { Stmt4[i0] : i0 >= p_0 and 0 <= i0 <= 1023 and 2i0 > p_0 };
+; UNNAMED-NEXT:             Schedule :=
+; UNNAMED-NEXT:                 [p_0] -> { Stmt4[i0] -> [i0, 1] };
+; UNNAMED-NEXT:             MustWriteAccess :=	[Reduction Type: NONE] [Scalar: 1]
+; UNNAMED-NEXT:                 [p_0] -> { Stmt4[i0] -> MemRef0__phi[] };
+; UNNAMED-NEXT:     	Stmt5
+; UNNAMED-NEXT:             Domain :=
+; UNNAMED-NEXT:                 [p_0] -> { Stmt5[0] : p_0 = 0 };
+; UNNAMED-NEXT:             Schedule :=
+; UNNAMED-NEXT:                 [p_0] -> { Stmt5[i0] -> [0, 0] };
+; UNNAMED-NEXT:             MustWriteAccess :=	[Reduction Type: NONE] [Scalar: 1]
+; UNNAMED-NEXT:                 [p_0] -> { Stmt5[i0] -> MemRef0__phi[] };
+; UNNAMED-NEXT:     	Stmt6
+; UNNAMED-NEXT:             Domain :=
+; UNNAMED-NEXT:                 [p_0] -> { Stmt6[i0] : 0 <= i0 <= 1023 };
+; UNNAMED-NEXT:             Schedule :=
+; UNNAMED-NEXT:                 [p_0] -> { Stmt6[i0] -> [i0, 3] };
+; UNNAMED-NEXT:             ReadAccess :=	[Reduction Type: NONE] [Scalar: 1]
+; UNNAMED-NEXT:                 [p_0] -> { Stmt6[i0] -> MemRef0__phi[] };
+; UNNAMED-NEXT:             ReadAccess :=	[Reduction Type: NONE] [Scalar: 0]
+; UNNAMED-NEXT:                 [p_0] -> { Stmt6[i0] -> MemRef1[o0] };
+; UNNAMED-NEXT:             MayWriteAccess :=	[Reduction Type: NONE] [Scalar: 0]
+; UNNAMED-NEXT:                 [p_0] -> { Stmt6[i0] -> MemRef1[o0] };
+; UNNAMED-NEXT:     }
+
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+
+define void @f(i32* %A, i32 %b) {
+bb:
+  br label %bb1
+
+bb1:                                              ; preds = %bb19, %bb
+  %i.0 = phi i32 [ 0, %bb ], [ %tmp20, %bb19 ]
+  %exitcond = icmp ne i32 %i.0, 1024
+  br i1 %exitcond, label %bb2, label %bb21
+
+bb2:                                              ; preds = %bb1
+  %tmp = icmp slt i32 %i.0, %b
+  br i1 %tmp, label %bb3, label %bb4
+
+bb3:                                              ; preds = %bb2
+  br label %bb10
+
+bb4:                                              ; preds = %bb2
+  %tmp5 = mul nsw i32 %i.0, 2
+  %tmp6 = icmp sgt i32 %tmp5, %b
+  br i1 %tmp6, label %bb7, label %bb8
+
+bb7:                                              ; preds = %bb4
+  br label %bb10
+
+bb8:                                              ; preds = %bb4
+  br label %bb10
+
+bb10:                                             ; preds = %bb9, %bb3
+  %x.1 = phi i32 [ 0, %bb3 ], [ 3, %bb7 ], [ %b, %bb8 ]
+  %tmp11 = sext i32 %x.1 to i64
+  %tmp12 = getelementptr inbounds i32, i32* %A, i64 %tmp11
+  %tmp13 = load i32,  i32* %tmp12, align 4
+  %tmp14 = icmp eq i32 %tmp13, 0
+  br i1 %tmp14, label %bb18, label %bb15
+
+bb15:                                             ; preds = %bb10
+  %tmp16 = sext i32 %x.1 to i64
+  %tmp17 = getelementptr inbounds i32, i32* %A, i64 %tmp16
+  store i32 0, i32* %tmp17, align 4
+  br label %bb18
+
+bb18:                                             ; preds = %bb10, %bb15
+  br label %bb19
+
+bb19:                                             ; preds = %bb18
+  %tmp20 = add nuw nsw i32 %i.0, 1
+  br label %bb1
+
+bb21:                                             ; preds = %bb1
+  ret void
+}
diff --git a/polly/test/ScopInfo/unnamed_stmts.ll b/polly/test/ScopInfo/unnamed_stmts.ll
new file mode 100644
index 00000000000..89d40c83575
--- /dev/null
+++ b/polly/test/ScopInfo/unnamed_stmts.ll
@@ -0,0 +1,148 @@
+; RUN: opt %loadPolly -polly-scops -analyze < %s | FileCheck %s
+
+; This test case verifies that we generate numbered statement names in case
+; no LLVM-IR names are used in the test case. We also verify, that we
+; distinguish statements named with a number and unnamed statements that happen
+; to have an index identical to a number used in a statement name.
+
+; CHECK: Arrays {
+; CHECK-NEXT:     float MemRef0[*][%n]; // Element size 4
+; CHECK-NEXT:     float MemRef1[*][%n]; // Element size 4
+; CHECK-NEXT: }
+; CHECK-NEXT: Arrays (Bounds as pw_affs) {
+; CHECK-NEXT:     float MemRef0[*][ [n] -> { [] -> [(n)] } ]; // Element size 4
+; CHECK-NEXT:     float MemRef1[*][ [n] -> { [] -> [(n)] } ]; // Element size 4
+; CHECK-NEXT: }
+
+; CHECK: Statements {
+; CHECK-NEXT: 	Stmt2
+; CHECK-NEXT:         Domain :=
+; CHECK-NEXT:             [n] -> { Stmt2[i0, i1] : 0 <= i0 < n and 0 <= i1 < n };
+; CHECK-NEXT:         Schedule :=
+; CHECK-NEXT:             [n] -> { Stmt2[i0, i1] -> [0, i0, i1, 0] };
+; CHECK-NEXT:         ReadAccess :=	[Reduction Type: NONE] [Scalar: 0]
+; CHECK-NEXT:             [n] -> { Stmt2[i0, i1] -> MemRef0[i0, i1] };
+; CHECK-NEXT:         ReadAccess :=	[Reduction Type: NONE] [Scalar: 0]
+; CHECK-NEXT:             [n] -> { Stmt2[i0, i1] -> MemRef1[i0, i1] };
+; CHECK-NEXT:         MustWriteAccess :=	[Reduction Type: NONE] [Scalar: 0]
+; CHECK-NEXT:             [n] -> { Stmt2[i0, i1] -> MemRef1[i0, i1] };
+; CHECK-NEXT: 	Stmt10
+; CHECK-NEXT:         Domain :=
+; CHECK-NEXT:             [n] -> { Stmt10[i0, i1] : 0 <= i0 < n and 0 <= i1 < n };
+; CHECK-NEXT:         Schedule :=
+; CHECK-NEXT:             [n] -> { Stmt10[i0, i1] -> [1, i0, i1, 0] };
+; CHECK-NEXT:         ReadAccess :=	[Reduction Type: NONE] [Scalar: 0]
+; CHECK-NEXT:             [n] -> { Stmt10[i0, i1] -> MemRef1[i0, i1] };
+; CHECK-NEXT:         ReadAccess :=	[Reduction Type: NONE] [Scalar: 0]
+; CHECK-NEXT:             [n] -> { Stmt10[i0, i1] -> MemRef0[i0, i1] };
+; CHECK-NEXT:         MustWriteAccess :=	[Reduction Type: NONE] [Scalar: 0]
+; CHECK-NEXT:             [n] -> { Stmt10[i0, i1] -> MemRef0[i0, i1] };
+; CHECK-NEXT: 	Stmt_2
+; CHECK-NEXT:         Domain :=
+; CHECK-NEXT:             [n] -> { Stmt_2[i0, i1] : 0 <= i0 < n and 0 <= i1 < n };
+; CHECK-NEXT:         Schedule :=
+; CHECK-NEXT:             [n] -> { Stmt_2[i0, i1] -> [1, i0, i1, 1] };
+; CHECK-NEXT:         MustWriteAccess :=	[Reduction Type: NONE] [Scalar: 0]
+; CHECK-NEXT:             [n] -> { Stmt_2[i0, i1] -> MemRef0[i0, i1]
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+
+; Function Attrs: nounwind uwtable
+define void @vec3(i64 %n, float*, float*) #0 {
+  br label %.split
+
+.split:                                           ; preds = %0
+  br label %.preheader2.lr.ph
+
+.preheader2.lr.ph:                                ; preds = %.split
+  br label %.preheader2
+
+.preheader2:                                      ; preds = %.preheader2.lr.ph, %15
+  %i.010 = phi i64 [ 0, %.preheader2.lr.ph ], [ %16, %15 ]
+  br label %.lr.ph8
+
+.lr.ph8:                                          ; preds = %.preheader2
+  br label %4
+
+..preheader1_crit_edge:                           ; preds = %15
+  br label %.preheader1
+
+.preheader1:                                      ; preds = %..preheader1_crit_edge, %.split
+  %3 = icmp sgt i64 %n, 0
+  br i1 %3, label %.preheader.lr.ph, label %"name"
+
+.preheader.lr.ph:                                 ; preds = %.preheader1
+  br label %.preheader
+
+; <label>:4:                                      ; preds = %.lr.ph8, %4
+  %j.07 = phi i64 [ 0, %.lr.ph8 ], [ %14, %4 ]
+  %5 = mul nsw i64 %i.010, %n
+  %6 = getelementptr inbounds float, float* %1, i64 %5
+  %7 = getelementptr inbounds float, float* %6, i64 %j.07
+  %8 = load float, float* %7, align 4
+  %9 = mul nsw i64 %i.010, %n
+  %10 = getelementptr inbounds float, float* %0, i64 %9
+  %11 = getelementptr inbounds float, float* %10, i64 %j.07
+  %12 = load float, float* %11, align 4
+  %13 = fadd float %8, %12
+  store float %13, float* %11, align 4
+  %14 = add nuw nsw i64 %j.07, 1
+  %exitcond13 = icmp ne i64 %14, %n
+  br i1 %exitcond13, label %4, label %._crit_edge9
+
+._crit_edge9:                                     ; preds = %4
+  br label %15
+
+; <label>:15:                                     ; preds = %._crit_edge9, %.preheader2
+  %16 = add nuw nsw i64 %i.010, 1
+  %exitcond14 = icmp ne i64 %16, %n
+  br i1 %exitcond14, label %.preheader2, label %..preheader1_crit_edge
+
+.preheader:                                       ; preds = %.preheader.lr.ph, %29
+  %i1.04 = phi i64 [ 0, %.preheader.lr.ph ], [ %30, %29 ]
+  %17 = icmp sgt i64 %n, 0
+  br i1 %17, label %.lr.ph, label %29
+
+.lr.ph:                                           ; preds = %.preheader
+  br label %18
+
+; <label>:18:                                     ; preds = %.lr.ph, %18
+  %j2.03 = phi i64 [ 0, %.lr.ph ], [ %28, %"2" ]
+  %19 = mul nsw i64 %i1.04, %n
+  %20 = getelementptr inbounds float, float* %0, i64 %19
+  %21 = getelementptr inbounds float, float* %20, i64 %j2.03
+  %22 = load float, float* %21, align 4
+  %23 = mul nsw i64 %i1.04, %n
+  %24 = getelementptr inbounds float, float* %1, i64 %23
+  %25 = getelementptr inbounds float, float* %24, i64 %j2.03
+  %26 = load float, float* %25, align 4
+  %27 = fadd float %22, %26
+  store float %27, float* %25, align 4
+  br label %"2"
+
+"2":
+  store float 42.0, float* %25
+  %28 = add nuw nsw i64 %j2.03, 1
+  %exitcond = icmp ne i64 %28, %n
+  br i1 %exitcond, label %18, label %._crit_edge
+
+._crit_edge:                                      ; preds = %18
+  br label %29
+
+; <label>:29:                                     ; preds = %._crit_edge, %.preheader
+  %30 = add nuw nsw i64 %i1.04, 1
+  %exitcond12 = icmp ne i64 %30, %n
+  br i1 %exitcond12, label %.preheader, label %._crit_edge6
+
+._crit_edge6:                                     ; preds = %29
+  br label %"name"
+
+"name":
+  ret void
+}
+
+attributes #0 = { nounwind uwtable "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+sse,+sse2" "unsafe-fp-math"="false" "use-soft-float"="false" }
+
+!llvm.ident = !{!0}
+
+!0 = !{!"Ubuntu clang version 3.7.1-3ubuntu4 (tags/RELEASE_371/final) (based on LLVM 3.7.1)"}
diff --git a/polly/test/lit.site.cfg.in b/polly/test/lit.site.cfg.in
index 71ec8ef46c3..f6e03e976ee 100644
--- a/polly/test/lit.site.cfg.in
+++ b/polly/test/lit.site.cfg.in
@@ -42,11 +42,13 @@ if config.link_polly_into_tools == '' or \
                                  + config.polly_lib_dir + '/LLVMPolly@LLVM_SHLIBEXT@'
                                  + ' -polly-process-unprofitable '
                                  + ' -polly-remarks-minimal '
+                                 + ' -polly-use-llvm-names '
                                  ))
 else:
     config.substitutions.append(('%loadPolly', ''
                                  + ' -polly-process-unprofitable '
                                  + ' -polly-remarks-minimal '
+                                 + ' -polly-use-llvm-names '
                                  ))
 
 if config.enable_gpgpu_codegen == 'TRUE' :