[llvm-commits] [llvm] r94548 - /llvm/trunk/lib/VMCore/Instructions.cpp

[Dan Gohman]

Author: djg
Date: Tue Jan 26 10:04:20 2010
New Revision: 94548

URL: http://llvm.org/viewvc/llvm-project?rev=94548&view=rev
Log:
Fix ICmpInst::makeConstantRange to use ConstantRange's API properly
in the case of empty and full ranges.

Modified:
    llvm/trunk/lib/VMCore/Instructions.cpp

Modified: llvm/trunk/lib/VMCore/Instructions.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/VMCore/Instructions.cpp?rev=94548&r1=94547&r2=94548&view=diff

==============================================================================
--- llvm/trunk/lib/VMCore/Instructions.cpp (original)
+++ llvm/trunk/lib/VMCore/Instructions.cpp Tue Jan 26 10:04:20 2010
@@ -2865,25 +2865,53 @@
   default: llvm_unreachable("Invalid ICmp opcode to ConstantRange ctor!");
   case ICmpInst::ICMP_EQ: Upper++; break;
   case ICmpInst::ICMP_NE: Lower++; break;
-  case ICmpInst::ICMP_ULT: Lower = APInt::getMinValue(BitWidth); break;
-  case ICmpInst::ICMP_SLT: Lower = APInt::getSignedMinValue(BitWidth); break;
+  case ICmpInst::ICMP_ULT:
+    Lower = APInt::getMinValue(BitWidth);
+    // Check for an empty-set condition.
+    if (Lower == Upper)
+      return ConstantRange(BitWidth, /*isFullSet=*/false);
+    break;
+  case ICmpInst::ICMP_SLT:
+    Lower = APInt::getSignedMinValue(BitWidth);
+    // Check for an empty-set condition.
+    if (Lower == Upper)
+      return ConstantRange(BitWidth, /*isFullSet=*/false);
+    break;
   case ICmpInst::ICMP_UGT: 
     Lower++; Upper = APInt::getMinValue(BitWidth);        // Min = Next(Max)
+    // Check for an empty-set condition.
+    if (Lower == Upper)
+      return ConstantRange(BitWidth, /*isFullSet=*/false);
     break;
   case ICmpInst::ICMP_SGT:
     Lower++; Upper = APInt::getSignedMinValue(BitWidth);  // Min = Next(Max)
+    // Check for an empty-set condition.
+    if (Lower == Upper)
+      return ConstantRange(BitWidth, /*isFullSet=*/false);
     break;
   case ICmpInst::ICMP_ULE: 
     Lower = APInt::getMinValue(BitWidth); Upper++; 
+    // Check for a full-set condition.
+    if (Lower == Upper)
+      return ConstantRange(BitWidth, /*isFullSet=*/true);
     break;
   case ICmpInst::ICMP_SLE: 
     Lower = APInt::getSignedMinValue(BitWidth); Upper++; 
+    // Check for a full-set condition.
+    if (Lower == Upper)
+      return ConstantRange(BitWidth, /*isFullSet=*/true);
     break;
   case ICmpInst::ICMP_UGE:
     Upper = APInt::getMinValue(BitWidth);        // Min = Next(Max)
+    // Check for a full-set condition.
+    if (Lower == Upper)
+      return ConstantRange(BitWidth, /*isFullSet=*/true);
     break;
   case ICmpInst::ICMP_SGE:
     Upper = APInt::getSignedMinValue(BitWidth);  // Min = Next(Max)
+    // Check for a full-set condition.
+    if (Lower == Upper)
+      return ConstantRange(BitWidth, /*isFullSet=*/true);
     break;
   }
   return ConstantRange(Lower, Upper);