builtins.c (expand_builtin_memcpy): Remove endp argument and endp != 0 handling.
* builtins.c (expand_builtin_memcpy): Remove endp argument and endp
!= 0 handling. Pass 0 to store_by_pieces.
(expand_builtin_mempcpy): Add endp argument. Don't call
expand_builtin_memcpy, call store_by_pieces resp. move_by_pieces
directly. If ignoring result, only do expand_call.
(expand_builtin_stpcpy): Likewise. Call expand_builtin_mempcpy
otherwise.
(expand_builtin_strncpy, expand_builtin_memset): Adjust
store_by_pices callers.
(expand_builtin): Adjust expand_builtin_memcpy and
expand_builtin_mempcpy callers.
* expr.c (can_move_by_pieces): New function.
(move_by_pieces): Add endp argument, return to resp. memory at end
or one byte earlier depending on endp.
(store_by_pieces): Likewise.
(emit_block_move): Adjust call to move_by_pieces.
(emit_push_insn): Adjust move_by_pieces caller.
* expr.h (can_move_by_pieces): New prototype.
(store_by_pieces): Adjust prototypes.
* rtl.h (move_by_pieces): Adjust prototype.
* config/mips/mips.c (expand_block_move): Adjust move_by_pieces
caller.
* gcc.c-torture/execute/builtins/string-4.c (main_test): Remove
mempcpy test with post-increments.
* gcc.c-torture/execute/string-opt-3.c: New test.
* gcc.dg/string-opt-1.c: New test.