[llvm-commits] [llvm] r73869 - in /llvm/trunk: include/llvm/Analysis/ScalarEvolution.h lib/Analysis/ScalarEvolution.cpp

[Dan Gohman]

Author: djg
Date: Sun Jun 21 22:18:45 2009
New Revision: 73869

URL: http://llvm.org/viewvc/llvm-project?rev=73869&view=rev
Log:
Factor out code for computing umin and smin for SCEV expressions into
helper functions. Based on a patch by Nick Lewycky.

Modified:
    llvm/trunk/include/llvm/Analysis/ScalarEvolution.h
    llvm/trunk/lib/Analysis/ScalarEvolution.cpp

Modified: llvm/trunk/include/llvm/Analysis/ScalarEvolution.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Analysis/ScalarEvolution.h?rev=73869&r1=73868&r2=73869&view=diff

==============================================================================
--- llvm/trunk/include/llvm/Analysis/ScalarEvolution.h (original)
+++ llvm/trunk/include/llvm/Analysis/ScalarEvolution.h Sun Jun 21 22:18:45 2009
@@ -494,6 +494,8 @@
     SCEVHandle getSMaxExpr(SmallVectorImpl<SCEVHandle> &Operands);
     SCEVHandle getUMaxExpr(const SCEVHandle &LHS, const SCEVHandle &RHS);
     SCEVHandle getUMaxExpr(SmallVectorImpl<SCEVHandle> &Operands);
+    SCEVHandle getSMinExpr(const SCEVHandle &LHS, const SCEVHandle &RHS);
+    SCEVHandle getUMinExpr(const SCEVHandle &LHS, const SCEVHandle &RHS);
     SCEVHandle getUnknown(Value *V);
     SCEVHandle getCouldNotCompute();
 

Modified: llvm/trunk/lib/Analysis/ScalarEvolution.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/ScalarEvolution.cpp?rev=73869&r1=73868&r2=73869&view=diff

==============================================================================
--- llvm/trunk/lib/Analysis/ScalarEvolution.cpp (original)
+++ llvm/trunk/lib/Analysis/ScalarEvolution.cpp Sun Jun 21 22:18:45 2009
@@ -1903,6 +1903,18 @@
   return Result;
 }
 
+SCEVHandle ScalarEvolution::getSMinExpr(const SCEVHandle &LHS,
+                                        const SCEVHandle &RHS) {
+  // ~smax(~x, ~y) == smin(x, y).
+  return getNotSCEV(getSMaxExpr(getNotSCEV(LHS), getNotSCEV(RHS)));
+}
+
+SCEVHandle ScalarEvolution::getUMinExpr(const SCEVHandle &LHS,
+                                        const SCEVHandle &RHS) {
+  // ~umax(~x, ~y) == umin(x, y)
+  return getNotSCEV(getUMaxExpr(getNotSCEV(LHS), getNotSCEV(RHS)));
+}
+
 SCEVHandle ScalarEvolution::getUnknown(Value *V) {
   if (ConstantInt *CI = dyn_cast<ConstantInt>(V))
     return getConstant(CI);
@@ -2644,10 +2656,7 @@
         if (LHS == U->getOperand(1) && RHS == U->getOperand(2))
           return getSMaxExpr(getSCEV(LHS), getSCEV(RHS));
         else if (LHS == U->getOperand(2) && RHS == U->getOperand(1))
-          // ~smax(~x, ~y) == smin(x, y).
-          return getNotSCEV(getSMaxExpr(
-                                   getNotSCEV(getSCEV(LHS)),
-                                   getNotSCEV(getSCEV(RHS))));
+          return getSMinExpr(getSCEV(LHS), getSCEV(RHS));
         break;
       case ICmpInst::ICMP_ULT:
       case ICmpInst::ICMP_ULE:
@@ -2658,9 +2667,7 @@
         if (LHS == U->getOperand(1) && RHS == U->getOperand(2))
           return getUMaxExpr(getSCEV(LHS), getSCEV(RHS));
         else if (LHS == U->getOperand(2) && RHS == U->getOperand(1))
-          // ~umax(~x, ~y) == umin(x, y)
-          return getNotSCEV(getUMaxExpr(getNotSCEV(getSCEV(LHS)),
-                                        getNotSCEV(getSCEV(RHS))));
+          return getUMinExpr(getSCEV(LHS), getSCEV(RHS));
         break;
       case ICmpInst::ICMP_NE:
         // n != 0 ? n : 1  ->  umax(n, 1)