Changes in directory llvm/lib/Transforms/Scalar:
InstructionCombining.cpp updated: 1.520 -> 1.521 --- Log message: Fix bug in PR454: http://llvm.org/PR454 resolution. Added new test case. This fixes llvmAsmParser.cpp miscompile by llvm on PowerPC Darwin. --- Diffs of the changes: (+15 -1) InstructionCombining.cpp | 16 +++++++++++++++- 1 files changed, 15 insertions(+), 1 deletion(-) Index: llvm/lib/Transforms/Scalar/InstructionCombining.cpp diff -u llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.520 llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.521 --- llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.520 Mon Oct 16 18:08:08 2006 +++ llvm/lib/Transforms/Scalar/InstructionCombining.cpp Thu Oct 19 13:54:08 2006 @@ -4785,7 +4785,21 @@ Constant *Res = ConstantExpr::getCast(CI, SrcTy); if (ConstantExpr::getCast(Res, DestTy) == CI) { - RHSCIOp = Res; + // Make sure that src sign and dest sign match. For example, + // + // %A = cast short %X to uint + // %B = setgt uint %A, 1330 + // + // It is incorrect to transformt this into + // + // %B = setgt short %X, 1330 + // + // because %A may have negative value. + // However, it is OK if SrcTy is bool. See cast-set.ll testcase. + if (isSignSrc == isSignDest || SrcTy == Type::BoolTy) + RHSCIOp = Res; + else + return 0; } else { // If the value cannot be represented in the shorter type, we cannot emit // a simple comparison. _______________________________________________ llvm-commits mailing list llvm-commits@cs.uiuc.edu http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits
