[pushed] aarch64: Fix GTY markup for arm_sve.h [PR106491]

[Richard Sandiford <richard.sandiford@arm.com>]

It turns out that GTY(()) markers in definitions like:

  GTY(()) tree scalar_types[NUM_VECTOR_TYPES];

are not effective and are silently ignored.  The GTY(()) has
to come after an extern or static.

The externs associated with the SVE ACLE GTY variables are in
aarch64-sve-builtins.h.  This file is not in tm_include_list because
we don't want every target-facing file to include it.  It therefore
isn't in the list of GC header files either.

In this case that's a blessing in disguise, since the variables
belong to a namespace and gengtype doesn't understand namespaces.
I think the fix is instead to add an extra extern before each
variable declaration, similarly to varasm.cc and vtable-verify.cc.
(This works due to a "using namespace" at the end of the file.)

Tested on aarch64-linux-gnu & pushed.  I'll backport to branches
over the next few days.

Richard


gcc/
	PR target/106491
	* config/aarch64/aarch64-sve-builtins.cc (scalar_types)
	(acle_vector_types, acle_svpattern, acle_svprfop): Add GTY
	markup to (new) extern declarations instead of to the main
	definition.
---
 gcc/config/aarch64/aarch64-sve-builtins.cc | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/gcc/config/aarch64/aarch64-sve-builtins.cc b/gcc/config/aarch64/aarch64-sve-builtins.cc
index 9d78b270e47..12d9beee4da 100644
--- a/gcc/config/aarch64/aarch64-sve-builtins.cc
+++ b/gcc/config/aarch64/aarch64-sve-builtins.cc
@@ -530,7 +530,8 @@ static CONSTEXPR const function_group_info function_groups[] = {
 };
 
 /* The scalar type associated with each vector type.  */
-GTY(()) tree scalar_types[NUM_VECTOR_TYPES];
+extern GTY(()) tree scalar_types[NUM_VECTOR_TYPES];
+tree scalar_types[NUM_VECTOR_TYPES];
 
 /* The single-predicate and single-vector types, with their built-in
    "__SV..._t" name.  Allow an index of NUM_VECTOR_TYPES, which always
@@ -538,13 +539,16 @@ GTY(()) tree scalar_types[NUM_VECTOR_TYPES];
 static GTY(()) tree abi_vector_types[NUM_VECTOR_TYPES + 1];
 
 /* Same, but with the arm_sve.h "sv..._t" name.  */
-GTY(()) tree acle_vector_types[MAX_TUPLE_SIZE][NUM_VECTOR_TYPES + 1];
+extern GTY(()) tree acle_vector_types[MAX_TUPLE_SIZE][NUM_VECTOR_TYPES + 1];
+tree acle_vector_types[MAX_TUPLE_SIZE][NUM_VECTOR_TYPES + 1];
 
 /* The svpattern enum type.  */
-GTY(()) tree acle_svpattern;
+extern GTY(()) tree acle_svpattern;
+tree acle_svpattern;
 
 /* The svprfop enum type.  */
-GTY(()) tree acle_svprfop;
+extern GTY(()) tree acle_svprfop;
+tree acle_svprfop;
 
 /* The list of all registered function decls, indexed by code.  */
 static GTY(()) vec<registered_function *, va_gc> *registered_functions;
-- 
2.25.1