[Patch 2/7, Arm, GCC] Add option -mbranch-protection.

[Tejas Belagod]

Hi,

Add -mbranch-protection option and its associated parsing routines.
This option enables the code-generation of pointer signing and
authentication instructions in function prologues and epilogues.

Tested on arm-none-eabi. OK for trunk?

2021-10-04  Tejas Belagod  <tbelagod@arm.com>

gcc/ChangeLog:

	* common/config/arm/arm-common.c
	 (arm_print_hit_for_pacbti_option): New.
	 (arm_progress_next_token): New.
	 (arm_parse_pac_ret_clause): New routine for parsing the
	pac-ret clause for -mbranch-protection.
	(arm_parse_pacbti_option): New routine to parse all the options
	to -mbranch-protection.
	* config/arm/arm-protos.h (arm_parse_pacbti_option): Export.
	* config/arm/arm.c (arm_configure)build_target): Handle option
	to -mbranch-protection.
	* config/arm/arm.opt (mbranch-protection). New.
	(arm_enable_pacbti): New.
-------------- next part --------------
An embedded and charset-unspecified text was scrubbed...
Name: branch-prot.txt
URL: <https://gcc.gnu.org/pipermail/gcc-patches/attachments/20211008/04347bf3/attachment.txt>