jit: reset state in varasm.cc [PR117275]

PR jit/117275 reports various jit test failures seen on
powerpc64le-unknown-linux-gnu due to hitting this assertion
in varasm.cc on the 2nd compilation in a process:

#2  0x00007ffff63e67d0 in assemble_external_libcall (fun=0x7ffff2a4b1d8)
    at ../../src/gcc/varasm.cc:2650
2650          gcc_assert (!pending_assemble_externals_processed);
(gdb) p pending_assemble_externals_processed
$1 = true

We're not properly resetting state in varasm.cc after a compile
for libgccjit.

Fixed thusly.

gcc/ChangeLog:
	PR jit/117275
	* toplev.cc (toplev::finalize): Call varasm_cc_finalize.
	* varasm.cc (varasm_cc_finalize): New.
	* varasm.h (varasm_cc_finalize): New decl.

Signed-off-by: David Malcolm <dmalcolm@redhat.com>

gcc/toplev.cc

@@ -2433,6 +2433,7 @@ toplev::finalize (void)
   ira_costs_cc_finalize ();
   tree_cc_finalize ();
   reginfo_cc_finalize ();
+  varasm_cc_finalize ();
 
   /* save_decoded_options uses opts_obstack, so these must
      be cleaned up together.  */

gcc/varasm.cc

@@ -8854,4 +8854,57 @@ handle_vtv_comdat_section (section *sect, const_tree decl ATTRIBUTE_UNUSED)
   switch_to_comdat_section(sect, DECL_NAME (decl));
 }
 
+void
+varasm_cc_finalize ()
+{
+  first_global_object_name = nullptr;
+  weak_global_object_name = nullptr;
+
+  const_labelno = 0;
+  size_directive_output = 0;
+
+  last_assemble_variable_decl = NULL_TREE;
+  first_function_block_is_cold = false;
+  saw_no_split_stack = false;
+  text_section = nullptr;
+  data_section = nullptr;
+  readonly_data_section = nullptr;
+  sdata_section = nullptr;
+  ctors_section = nullptr;
+  dtors_section = nullptr;
+  bss_section = nullptr;
+  sbss_section = nullptr;
+  tls_comm_section = nullptr;
+  comm_section = nullptr;
+  lcomm_section = nullptr;
+  bss_noswitch_section = nullptr;
+  exception_section = nullptr;
+  eh_frame_section = nullptr;
+  in_section = nullptr;
+  in_cold_section_p = false;
+  cold_function_name = NULL_TREE;
+  unnamed_sections = nullptr;
+  section_htab = nullptr;
+  object_block_htab = nullptr;
+  anchor_labelno = 0;
+  shared_constant_pool = nullptr;
+  pending_assemble_externals = NULL_TREE;
+  pending_libcall_symbols = nullptr;
+
+#ifdef ASM_OUTPUT_EXTERNAL
+  pending_assemble_externals_processed = false;
+  pending_assemble_externals_set = nullptr;
+#endif
+
+  weak_decls = NULL_TREE;
+  initial_trampoline = nullptr;
+  const_desc_htab = nullptr;
+  weakref_targets = NULL_TREE;
+  alias_pairs = nullptr;
+  tm_clone_hash = nullptr;
+  trampolines_created = 0;
+  elf_init_array_section = nullptr;
+  elf_fini_array_section = nullptr;
+}
+
 #include "gt-varasm.h"

gcc/varasm.h

@@ -81,4 +81,6 @@ extern rtx assemble_trampoline_template (void);
 
 extern void switch_to_comdat_section (section *, tree);
 
+extern void varasm_cc_finalize ();
+
 #endif  // GCC_VARASM_H