tree 22ff6683e796ecc8eba8f949304a24e376528fa2
parent d1a23d573d5408be1cf52358fe03df0bfa07e16e
author Chris Lattner <sabre@nondot.org> 1192257354 +0000
committer Chris Lattner <sabre@nondot.org> 1192257354 +0000

Add a simple optimization to simplify the input to
truncate and truncstore instructions, based on the 
knowledge that they don't demand the top bits.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42952 91177308-0d34-0410-b5e6-96231b3b80d8