[gcc(refs/vendors/ARM/heads/morello)] morello: fix selftest::read_rtl_function_c_tests

[gcc(refs/vendors/ARM/heads/morello)] morello: fix selftest::read_rtl_function_c_tests

[Szabolcs Nagy]

https://gcc.gnu.org/g:4662bd2ad61743ca6083b9a7fecf169786765827

commit 4662bd2ad61743ca6083b9a7fecf169786765827
Author: Szabolcs Nagy <szabolcs.nagy@arm.com>
Date:   Wed Apr 13 16:28:30 2022 +0100

    morello: fix selftest::read_rtl_function_c_tests
    
    Without this patch building a default purecap ABI gcc fails because
    current_function_decl is NULL in aarch64_function_arg_regno_p.
    Unconditionally return true for r9 with purecap ABI since the arg
    regno predicate is not supposed to be context sensitive.
    
    /B/gcc/xgcc -B/B/gcc/ -xc -nostdinc /dev/null -S -o /dev/null -fself-test=/S/gcc/testsuite/selftests
    cc1: internal compiler error: Segmentation fault
    0xdefe6b crash_signal
            /S/gcc/toplev.c:327
    0x126ba20 contains_struct_check(tree_node*, tree_node_structure_enum, char const*, int, char const*)
            /S/gcc/tree.h:3474
    0x126ba20 aarch64_current_function_variadic_p
            /S/gcc/config/aarch64/aarch64.c:6704
    0x126ba20 aarch64_function_arg_regno_p(unsigned int)
            /S/gcc/config/aarch64/aarch64.c:6716
    0x7cd14b init_alias_target()
            /S/gcc/alias.c:3305
    0xdf13e7 backend_init_target
            /S/gcc/toplev.c:1896
    0xdf13e7 initialize_rtl()
            /S/gcc/toplev.c:1978
    0xd13963 read_rtl_function_body(char const*)
            /S/gcc/read-rtl-function.c:1628
    0xd9de03 selftest::rtl_dump_test::rtl_dump_test(selftest::location const&, char*)
            /S/gcc/selftest-rtl.c:92
    0xd1002b test_loading_dump_fragment_1
            /S/gcc/read-rtl-function.c:1757
    0xd13c63 selftest::read_rtl_function_c_tests()
            /S/gcc/read-rtl-function.c:2208
    0x1c16827 selftest::run_tests()
            /S/gcc/selftest-run-tests.c:90
    0xdf1867 toplev::run_self_tests()
            /S/gcc/toplev.c:2379
    Please submit a full bug report,
    with preprocessed source if appropriate.
    Please include the complete backtrace with any bug report.
    See <https://gcc.gnu.org/bugs/> for instructions.
    /S/gcc/c/Make-lang.in:124: recipe for target 's-selftest-c' failed
    make[2]: *** [s-selftest-c] Error 1

Diff:
---
 gcc/config/aarch64/aarch64.c | 13 +------------
 1 file changed, 1 insertion(+), 12 deletions(-)

diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index f49b46fc36b..1e7ab8ef9ac 100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -6698,22 +6698,11 @@ aarch64_function_arg_advance (cumulative_args_t pcum_v,
     }
 }
 
-static bool
-aarch64_current_function_variadic_p (void)
-{
-  tree t = TREE_TYPE (current_function_decl);
-  for (t = TYPE_ARG_TYPES (t); t; t = TREE_CHAIN (t))
-    if (t == void_list_node)
-      return false;
-
-  return true;
-}
-
 bool
 aarch64_function_arg_regno_p (unsigned regno)
 {
   if (TARGET_CAPABILITY_PURE && regno == R9_REGNUM)
-    return aarch64_current_function_variadic_p ();
+    return true;
 
   return ((GP_REGNUM_P (regno) && regno < R0_REGNUM + NUM_ARG_REGS)
 	  || (FP_REGNUM_P (regno) && regno < V0_REGNUM + NUM_FP_ARG_REGS));