From b5fdfb96121e001366654f4936f5f0d6c0ced33f Mon Sep 17 00:00:00 2001 From: Chris Lattner Date: Thu, 6 Dec 2007 07:44:31 +0000 Subject: Actually, disable this code for now. More analysis and improvements to the X86 backend are needed before this should be enabled by default. llvm-svn: 44657 --- llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp') diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index 918db383530..ba3c0ac33dc 100644 --- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -2134,6 +2134,12 @@ SDOperand DAGCombiner::visitXOR(SDNode *N) { /// visitShiftByConstant - Handle transforms common to the three shifts, when /// the shift amount is a constant. SDOperand DAGCombiner::visitShiftByConstant(SDNode *N, unsigned Amt) { + // FIXME: disable this for now. This pessimizes some common cases like: + // + //void foo(int *X, int i) { X[i & 1235] = 1; } + //int bar(int *X, int i) { return X[i & 255]; } + return SDOperand(); + SDNode *LHS = N->getOperand(0).Val; if (!LHS->hasOneUse()) return SDOperand(); -- cgit v1.2.3