aarch64,arm: Move branch-protection data to targets

The branch-protection types are target specific, not the same on arm
and aarch64.  This currently affects pac-ret+b-key, but there will be
a new type on aarch64 that is not relevant for arm.

After the move, change aarch_ identifiers to aarch64_ or arm_ as
appropriate.

Refactor aarch_validate_mbranch_protection to take the target specific
branch-protection types as an argument.

In case of invalid input currently no hints are provided: the way
branch-protection types and subtypes can be mixed makes it difficult
without causing confusion.

gcc/ChangeLog:

	* config/aarch64/aarch64.md: Rename aarch_ to aarch64_.
	* config/aarch64/aarch64.opt: Likewise.
	* config/aarch64/aarch64-c.cc (aarch64_update_cpp_builtins): Likewise.
	* config/aarch64/aarch64.cc (aarch64_expand_prologue): Likewise.
	(aarch64_expand_epilogue): Likewise.
	(aarch64_post_cfi_startproc): Likewise.
	(aarch64_handle_no_branch_protection): Copy and rename.
	(aarch64_handle_standard_branch_protection): Likewise.
	(aarch64_handle_pac_ret_protection): Likewise.
	(aarch64_handle_pac_ret_leaf): Likewise.
	(aarch64_handle_pac_ret_b_key): Likewise.
	(aarch64_handle_bti_protection): Likewise.
	(aarch64_override_options): Update branch protection validation.
	(aarch64_handle_attr_branch_protection): Likewise.
	* config/arm/aarch-common-protos.h (aarch_validate_mbranch_protection):
	Pass branch protection type description as argument.
	(struct aarch_branch_protect_type): Move from aarch-common.h.
	* config/arm/aarch-common.cc (aarch_handle_no_branch_protection):
	Remove.
	(aarch_handle_standard_branch_protection): Remove.
	(aarch_handle_pac_ret_protection): Remove.
	(aarch_handle_pac_ret_leaf): Remove.
	(aarch_handle_pac_ret_b_key): Remove.
	(aarch_handle_bti_protection): Remove.
	(aarch_validate_mbranch_protection): Pass branch protection type
	description as argument.
	* config/arm/aarch-common.h (enum aarch_key_type): Remove.
	(struct aarch_branch_protect_type): Remove.
	* config/arm/arm-c.cc (arm_cpu_builtins): Remove aarch_ra_sign_key.
	* config/arm/arm.cc (arm_handle_no_branch_protection): Copy and rename.
	(arm_handle_standard_branch_protection): Likewise.
	(arm_handle_pac_ret_protection): Likewise.
	(arm_handle_pac_ret_leaf): Likewise.
	(arm_handle_bti_protection): Likewise.
	(arm_configure_build_target): Update branch protection validation.
	* config/arm/arm.opt: Remove aarch_ra_sign_key.

1 files changed, 48 insertions, 7 deletions

diff --git a/gcc/config/arm/arm.cc b/gcc/config/arm/arm.cc
index 6a35fe4..0217abc 100644
--- a/gcc/config/arm/arm.cc
+++ b/gcc/config/arm/arm.cc
@@ -3259,6 +3259,52 @@ static sbitmap isa_all_fpubits_internal;
 static sbitmap isa_all_fpbits;
 static sbitmap isa_quirkbits;
 
+static void
+arm_handle_no_branch_protection (void)
+{
+  aarch_ra_sign_scope = AARCH_FUNCTION_NONE;
+  aarch_enable_bti = 0;
+}
+
+static void
+arm_handle_standard_branch_protection (void)
+{
+  aarch_ra_sign_scope = AARCH_FUNCTION_NON_LEAF;
+  aarch_enable_bti = 1;
+}
+
+static void
+arm_handle_pac_ret_protection (void)
+{
+  aarch_ra_sign_scope = AARCH_FUNCTION_NON_LEAF;
+}
+
+static void
+arm_handle_pac_ret_leaf (void)
+{
+  aarch_ra_sign_scope = AARCH_FUNCTION_ALL;
+}
+
+static void
+arm_handle_bti_protection (void)
+{
+  aarch_enable_bti = 1;
+}
+
+static const struct aarch_branch_protect_type arm_pac_ret_subtypes[] = {
+  { "leaf", false, arm_handle_pac_ret_leaf, NULL, 0 },
+  { NULL, false, NULL, NULL, 0 }
+};
+
+static const struct aarch_branch_protect_type arm_branch_protect_types[] = {
+  { "none", true, arm_handle_no_branch_protection, NULL, 0 },
+  { "standard", true, arm_handle_standard_branch_protection, NULL, 0 },
+  { "pac-ret", false, arm_handle_pac_ret_protection, arm_pac_ret_subtypes,
+    ARRAY_SIZE (arm_pac_ret_subtypes) },
+  { "bti", false, arm_handle_bti_protection, NULL, 0 },
+  { NULL, false, NULL, NULL, 0 }
+};
+
 /* Configure a build target TARGET from the user-specified options OPTS and
    OPTS_SET.  If WARN_COMPATIBLE, emit a diagnostic if both the CPU and
    architecture have been specified, but the two are not identical.  */
@@ -3306,14 +3352,9 @@ arm_configure_build_target (struct arm_build_target *target,
 
   if (opts->x_arm_branch_protection_string)
     {
-      aarch_validate_mbranch_protection (opts->x_arm_branch_protection_string,
+      aarch_validate_mbranch_protection (arm_branch_protect_types,
+					 opts->x_arm_branch_protection_string,
 					 "-mbranch-protection=");
-
-      if (aarch_ra_sign_key != AARCH_KEY_A)
-	{
-	  warning (0, "invalid key type for %<-mbranch-protection=%>");
-	  aarch_ra_sign_key = AARCH_KEY_A;
-	}
     }
 
   if (arm_selected_arch)