Implement protection of global variables
This patch implements the protection of global variables. See the
comments appended to the beginning of the asan.c file.
* varasm.c: Include asan.h.
(assemble_noswitch_variable): Grow size by asan_red_zone_size
if decl is asan protected.
(place_block_symbol): Likewise.
(assemble_variable): If decl is asan protected, increase
DECL_ALIGN if needed, and for decls emitted using
assemble_variable_contents append padding zeros after it.
* Makefile.in (varasm.o): Depend on asan.h.
* asan.c: Include output.h.
(asan_pp, asan_pp_initialized, asan_ctor_statements): New variables.
(asan_pp_initialize, asan_pp_string): New functions.
(asan_emit_stack_protection): Use asan_pp{,_initialized}
instead of local pp{,_initialized} vars, use asan_pp_initialize
and asan_pp_string helpers.
(asan_needs_local_alias, asan_protect_global,
asan_global_struct, asan_add_global): New functions.
(asan_finish_file): Protect global vars that can be protected. Use
asan_ctor_statements instead of ctor_statements
* asan.h (asan_protect_global): New prototype.
(asan_red_zone_size): New inline function.
Co-Authored-By: Wei Mi <wmi@google.com>
From-SVN: r193437