[llvm-commits] [llvm] r106764 - /llvm/trunk/lib/Transforms/Scalar/LoopStrengthReduce.cpp

[Dan Gohman]

Author: djg
Date: Thu Jun 24 11:57:52 2010
New Revision: 106764

URL: http://llvm.org/viewvc/llvm-project?rev=106764&view=rev
Log:
A few minor micro-optimizations.

Modified:
    llvm/trunk/lib/Transforms/Scalar/LoopStrengthReduce.cpp

Modified: llvm/trunk/lib/Transforms/Scalar/LoopStrengthReduce.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/LoopStrengthReduce.cpp?rev=106764&r1=106763&r2=106764&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/LoopStrengthReduce.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/LoopStrengthReduce.cpp Thu Jun 24 11:57:52 2010
@@ -449,6 +449,7 @@
       if (!Step) return 0;
       return SE.getAddRecExpr(Start, Step, AR->getLoop());
     }
+    return 0;
   }
 
   // Distribute the sdiv over add operands, if the add doesn't overflow.
@@ -464,10 +465,11 @@
       }
       return SE.getAddExpr(Ops);
     }
+    return 0;
   }
 
   // Check for a multiply operand that we can pull RHS out of.
-  if (const SCEVMulExpr *Mul = dyn_cast<SCEVMulExpr>(LHS))
+  if (const SCEVMulExpr *Mul = dyn_cast<SCEVMulExpr>(LHS)) {
     if (IgnoreSignificantBits || isMulSExtable(Mul, SE)) {
       SmallVector<const SCEV *, 4> Ops;
       bool Found = false;
@@ -484,6 +486,8 @@
       }
       return Found ? SE.getMulExpr(Ops) : 0;
     }
+    return 0;
+  }
 
   // Otherwise we don't know.
   return 0;
@@ -2397,13 +2401,12 @@
   for (SmallSetVector<int64_t, 8>::const_iterator
        I = Factors.begin(), E = Factors.end(); I != E; ++I) {
     int64_t Factor = *I;
-    Formula F = Base;
 
     // Check that the multiplication doesn't overflow.
-    if (F.AM.BaseOffs == INT64_MIN && Factor == -1)
+    if (Base.AM.BaseOffs == INT64_MIN && Factor == -1)
       continue;
-    F.AM.BaseOffs = (uint64_t)Base.AM.BaseOffs * Factor;
-    if (F.AM.BaseOffs / Factor != Base.AM.BaseOffs)
+    int64_t NewBaseOffs = (uint64_t)Base.AM.BaseOffs * Factor;
+    if (NewBaseOffs / Factor != Base.AM.BaseOffs)
       continue;
 
     // Check that multiplying with the use offset doesn't overflow.
@@ -2414,6 +2417,9 @@
     if (Offset / Factor != LU.MinOffset)
       continue;
 
+    Formula F = Base;
+    F.AM.BaseOffs = NewBaseOffs;
+
     // Check that this scale is legal.
     if (!isLegalUse(F.AM, Offset, Offset, LU.Kind, LU.AccessTy, TLI))
       continue;