[llvm-commits] [llvm] r39896 - /llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp

[Chris Lattner]

Author: lattner
Date: Sun Jul 15 23:15:34 2007
New Revision: 39896

URL: http://llvm.org/viewvc/llvm-project?rev=39896&view=rev
Log:
Repair a regression in Transforms/InstCombine/mul.ll that Reid noticed.

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

Modified: llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp?rev=39896&r1=39895&r2=39896&view=diff

==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp Sun Jul 15 23:15:34 2007
@@ -2286,9 +2286,22 @@
   case ICmpInst::ICMP_SLT:   // True if LHS s< 0
     TrueIfSigned = true;
     return RHS->isZero();
+  case ICmpInst::ICMP_SLE:   // True if LHS s<= RHS and RHS == -1
+    TrueIfSigned = true;
+    return RHS->isAllOnesValue();
   case ICmpInst::ICMP_SGT:   // True if LHS s> -1
     TrueIfSigned = false;
     return RHS->isAllOnesValue();
+  case ICmpInst::ICMP_UGT:
+    // True if LHS u> RHS and RHS == high-bit-mask - 1
+    TrueIfSigned = true;
+    return RHS->getValue() ==
+      APInt::getSignedMaxValue(RHS->getType()->getPrimitiveSizeInBits());
+  case ICmpInst::ICMP_UGE: 
+    // True if LHS u>= RHS and RHS == high-bit-mask (2^7, 2^15, 2^31, etc)
+    TrueIfSigned = true;
+    return RHS->getValue() == 
+      APInt::getSignBit(RHS->getType()->getPrimitiveSizeInBits());
   default:
     return false;
   }