[polly] r269044 - Expose interpretAsUnsigned in the SCEVAffinator [NFC]

[Johannes Doerfert via llvm-commits]

Author: jdoerfert
Date: Tue May 10 06:45:46 2016
New Revision: 269044

URL: http://llvm.org/viewvc/llvm-project?rev=269044&view=rev
Log:
Expose interpretAsUnsigned in the SCEVAffinator [NFC]

  This exposes the functionality to interpret a SCEV, or better the
  piece-wise function created from the SCEV, as an unsigned value
  instead of a signed one.


Modified:
    polly/trunk/include/polly/Support/SCEVAffinator.h
    polly/trunk/lib/Analysis/ScopInfo.cpp
    polly/trunk/lib/Support/SCEVAffinator.cpp

Modified: polly/trunk/include/polly/Support/SCEVAffinator.h
URL: http://llvm.org/viewvc/llvm-project/polly/trunk/include/polly/Support/SCEVAffinator.h?rev=269044&r1=269043&r2=269044&view=diff
==============================================================================
--- polly/trunk/include/polly/Support/SCEVAffinator.h (original)
+++ polly/trunk/include/polly/Support/SCEVAffinator.h Tue May 10 06:45:46 2016
@@ -67,6 +67,9 @@ public:
   /// @brief Take the asumption that @p PWAC is non-negative.
   void takeNonNegativeAssumption(PWACtx &PWAC);
 
+  /// @brief Interpret the PWA in @p PWAC as an unsigned value.
+  void interpretAsUnsigned(__isl_keep PWACtx &PWAC, unsigned Width);
+
   /// @brief Check an <nsw> AddRec for the loop @p L is cached.
   bool hasNSWAddRecForLoop(llvm::Loop *L) const;
 

Modified: polly/trunk/lib/Analysis/ScopInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/polly/trunk/lib/Analysis/ScopInfo.cpp?rev=269044&r1=269043&r2=269044&view=diff
==============================================================================
--- polly/trunk/lib/Analysis/ScopInfo.cpp (original)
+++ polly/trunk/lib/Analysis/ScopInfo.cpp Tue May 10 06:45:46 2016
@@ -3797,6 +3797,11 @@ __isl_give PWACtx Scop::getPwAff(const S
   // handling cdoe to all users of this function.
   auto PWAC = Affinator.getPwAff(E, BB);
   if (PWAC.first) {
+    // TODO: We could use a heuristic and either use:
+    //         SCEVAffinator::takeNonNegativeAssumption
+    //       or
+    //         SCEVAffinator::interpretAsUnsigned
+    //       to deal with unsigned or "NonNegative" SCEVs.
     if (NonNegative)
       Affinator.takeNonNegativeAssumption(PWAC);
     return PWAC;

Modified: polly/trunk/lib/Support/SCEVAffinator.cpp
URL: http://llvm.org/viewvc/llvm-project/polly/trunk/lib/Support/SCEVAffinator.cpp?rev=269044&r1=269043&r2=269044&view=diff
==============================================================================
--- polly/trunk/lib/Support/SCEVAffinator.cpp (original)
+++ polly/trunk/lib/Support/SCEVAffinator.cpp Tue May 10 06:45:46 2016
@@ -127,6 +127,16 @@ SCEVAffinator::~SCEVAffinator() {
     freePWACtx(CachedPair.second);
 }
 
+void SCEVAffinator::interpretAsUnsigned(__isl_keep PWACtx &PWAC,
+                                        unsigned Width) {
+  auto *PWA = PWAC.first;
+  auto *NonNegDom = isl_pw_aff_nonneg_set(isl_pw_aff_copy(PWA));
+  auto *NonNegPWA = isl_pw_aff_intersect_domain(isl_pw_aff_copy(PWA),
+                                                isl_set_copy(NonNegDom));
+  auto *ExpPWA = getWidthExpValOnDomain(Width, isl_set_complement(NonNegDom));
+  PWAC.first = isl_pw_aff_union_add(NonNegPWA, isl_pw_aff_add(PWA, ExpPWA));
+}
+
 void SCEVAffinator::takeNonNegativeAssumption(PWACtx &PWAC) {
   auto *NegPWA = isl_pw_aff_neg(isl_pw_aff_copy(PWAC.first));
   auto *NegDom = isl_pw_aff_pos_set(NegPWA);
@@ -353,12 +363,7 @@ SCEVAffinator::visitZeroExtendExpr(const
 
   // If the width is small build the piece for the non-negative part and
   // the one for the negative part and unify them.
-  auto *NonNegDom = isl_pw_aff_nonneg_set(isl_pw_aff_copy(OpPWAC.first));
-  auto *NonNegPWA = isl_pw_aff_intersect_domain(isl_pw_aff_copy(OpPWAC.first),
-                                                isl_set_copy(NonNegDom));
-  auto *ExpPWA = getWidthExpValOnDomain(Width, isl_set_complement(NonNegDom));
-  OpPWAC.first = isl_pw_aff_add(OpPWAC.first, ExpPWA);
-  OpPWAC.first = isl_pw_aff_union_add(NonNegPWA, OpPWAC.first);
+  interpretAsUnsigned(OpPWAC, Width);
   return OpPWAC;
 }