11edd87390
Adds a IfConverter pass that right now recognizes two simple patterns cond ? 0 : 2^n and cond ? x : x+-1 that can be generated without branches on ia32 and x64 using setcc instruction. R=fschneider@google.com Review URL: https://codereview.chromium.org//14057004 git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@21207 260f80e4-7a28-3924-810f-c04153c831b5