[Bug rtl-optimization/66152] [9 Regression] suboptimal load bytes to stack

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66152

--- Comment #8 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Author: jakub
Date: Sat Feb 16 11:20:33 2019
New Revision: 268957

URL: https://gcc.gnu.org/viewcvs?rev=268957&root=gcc&view=rev
Log:
        PR rtl-optimization/66152
        * builtins.h (c_readstr): Declare.
        * builtins.c (c_readstr): Remove forward declaration.  Add
        null_terminated_p argument, if false, read all bytes from the
        string instead of stopping after '\0'.
        * expr.c (string_cst_read_str): New function.
        (store_expr): Use string_cst_read_str instead of
        builtin_strncpy_read_str.  Try to store by pieces the whole
        exp_len first, and only if that fails, split it up into
        store by pieces followed by clear_storage.  Formatting fix.

        * gcc.target/i386/pr66152.c: New test.

Added:
    trunk/gcc/testsuite/gcc.target/i386/pr66152.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/builtins.c
    trunk/gcc/builtins.h
    trunk/gcc/expr.c
    trunk/gcc/testsuite/ChangeLog