[Bug tree-optimization/80934] bzero should be assumed not to escape pointer argument

[msebor at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80934

--- Comment #3 from Martin Sebor <msebor at gcc dot gnu.org> ---
Author: msebor
Date: Fri Jun 16 20:52:03 2017
New Revision: 249278

URL: https://gcc.gnu.org/viewcvs?rev=249278&root=gcc&view=rev
Log:
PR tree-optimization/80934 - bzero should be assumed not to escape pointer
argument
PR tree-optimization/80933 - redundant bzero/bcopy calls not eliminated

gcc/ChangeLog:

        PR tree-optimization/80933
        PR tree-optimization/80934
        * builtins.c (fold_builtin_3): Do not handle bcmp here.
        * gimple-fold.c (gimple_fold_builtin_bcmp): New function.
        (gimple_fold_builtin_bcopy, gimple_fold_builtin_bzero): Likewise.
        (gimple_fold_builtin): Call them.

gcc/testsuite/ChangeLog:

        PR tree-optimization/80933
        PR tree-optimization/80934
        * gcc.dg/fold-bcopy.c: New test.
        * gcc.dg/tree-ssa/ssa-dse-30.c: Likewise..
        * gcc.dg/tree-ssa/alias-36.c: Likewise.
        * gcc/testsuite/gcc.dg/pr79214.c: Adjust.
        * gcc.dg/tree-prof/val-prof-7.c: Likewise.
        * gcc.dg/Wsizeof-pointer-memaccess1.c: Likewise.
        * gcc.dg/builtins-nonnull.c: Likewise.


Added:
    trunk/gcc/testsuite/gcc.dg/fold-bcopy.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/alias-36.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/ssa-dse-30.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/builtins.c
    trunk/gcc/gimple-fold.c
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gcc.dg/Wsizeof-pointer-memaccess1.c
    trunk/gcc/testsuite/gcc.dg/builtins-nonnull.c
    trunk/gcc/testsuite/gcc.dg/pr79214.c
    trunk/gcc/testsuite/gcc.dg/tree-prof/val-prof-7.c