re PR middle-end/53590 (compiler fails to generate SIMD instruction for FP division)
PR middle-end/53590
* common.opt (-fdelete-dead-exceptions): New switch.
* doc/invoke.texi (Code Gen Options): Document it.
* cse.c (count_reg_usage) <CALL_INSN>: Use !insn_nothrow_p in lieu of
insn_could_throw_p predicate. Do not skip an insn that could throw
if dead exceptions can be deleted.
(insn_live_p): Likewise, do not return true in that case.
* dce.c (can_alter_cfg): New flag.
(deletable_insn_p): Do not return false for an insn that can throw if
the CFG can be altered and dead exceptions can be deleted.
(init_dce): Set can_alter_cfg to false for fast DCE, true otherwise.
* dse.c (scan_insn): Use !insn_nothrow_p in lieu of insn_could_throw_
predicate. Do not preserve an insn that could throw if dead exceptions
can be deleted.
* function.h (struct function): Add can_delete_dead_exceptions flag.
* function.c (allocate_struct_function): Set it.
* lto-streamer-in.c (input_struct_function_base): Stream it.
* lto-streamer-out.c (input_struct_function_base): Likewise.
* tree-ssa-dce.c (mark_stmt_if_obviously_necessary): Do not mark a
statement that could throw as necessary if dead exceptions can be
deleted.
ada/
* gcc-interface/misc.c (gnat_init_options_struct): Set
opts->x_flag_delete_dead_exceptions to 1.