[Bug tree-optimization/67351] Missed optimisation on 64-bit field compared to 32-bit

naveenh at gcc dot gnu.org gcc-bugzilla@gcc.gnu.org
Thu Sep 3 10:20:00 GMT 2015


https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67351

--- Comment #9 from naveenh at gcc dot gnu.org ---
Author: naveenh
Date: Thu Sep  3 10:20:03 2015
New Revision: 227432

URL: https://gcc.gnu.org/viewcvs?rev=227432&root=gcc&view=rev
Log:
2015-09-03  Naveen H.S  <Naveen.Hurugalawadi@caviumnetworks.com>

        PR middle-end/67351

        gcc/ChangeLog: 
        * fold-const.c (fold_binary_loc) : Move 
        Transform (x >> c) << c into x & (-1<<c) or
        transform (x << c) >> c into x & ((unsigned)-1 >> c) for unsigned
        types using simplify and match.
        * match.pd (lshift (rshift @0 INTEGER_CST@1) @1) : New simplifier.
        (rshift (lshift @0 INTEGER_CST@1) @1) : New Simplifier.

        gcc/testsuite/ChangeLog: 
        * g++.dg/pr66752-2.C: New test.


Added:
    trunk/gcc/testsuite/g++.dg/pr67351.C
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/fold-const.c
    trunk/gcc/match.pd
    trunk/gcc/testsuite/ChangeLog



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