On 14/10/15 10:30, Jakub Jelinek wrote:
On Tue, Oct 13, 2015 at 02:16:23PM +0300, Maxim Ostapenko wrote:
This patch introduces required compiler changes. Now, we don't version
asan_init, we have a special __asan_version_mismatch_check_v[n] symbol for
this.
For this, I just have to wonder what is the actual improvement over what we
had. To me it looks like a step in the wrong direction, it will only bloat
the size of the ctors. I can live with it, but just want to put on record I
think it is a mistake.
Also, asan_stack_malloc_[n] doesn't take a local stack as a second parameter
anymore, so don't pass it.
I think this is another mistake, but this time with actually bad fix on the
compiler side for it. If I read the code well, previously
__asan_stack_malloc_n would return you the local stack if it failed for
whatever reason, which is actually what you want as fallback.
But, the new code returns NULL instead, so I think you would need to compare
the return value of __asan_stack_malloc_n with NULL and if it is NULL, use
the addr instead of what it returned; which is not what your asan.c change
does. Now, what is the improvement here? Bloat the compiler generated
code... :(
Ah, right, fixing this now. Does this looks better now?
2015-10-12 Maxim Ostapenko <m.ostape...@partner.samsung.com>
config/
* bootstrap-asan.mk: Replace ASAN_OPTIONS=detect_leaks with
LSAN_OPTIONS=detect_leaks
Missing . at the end, and the config/ hunk missing from the patch.
gcc/
* asan.c (asan_emit_stack_protection): Don't pass local stack to
asan_stack_malloc_[n] anymore.
(asan_finish_file): Instert __asan_version_mismatch_check_v[n] call.
s/Instert/Instead/
Fixed now.
Jakub
2015-10-12 Maxim Ostapenko <m.ostape...@partner.samsung.com>
config/
* bootstrap-asan.mk: Replace ASAN_OPTIONS=detect_leaks with
LSAN_OPTIONS=detect_leaks.
gcc/
* asan.c (asan_emit_stack_protection): Don't pass local stack to
asan_stack_malloc_[n] anymore. Check if asan_stack_malloc_[n] returned
NULL and use local stack than.
(asan_finish_file): Insert __asan_version_mismatch_check_v[n] call
in addition to __asan_init.
* sanitizer.def (BUILT_IN_ASAN_INIT): Rename to __asan_init.
(BUILT_IN_ASAN_VERSION_MISMATCH_CHECK): Add new builtin call.
gcc/testsuite/
g++.dg/asan/default-options-1.C: Adjust testcase.
Index: gcc/asan.c
===================================================================
--- gcc/asan.c (revision 228817)
+++ gcc/asan.c (working copy)
@@ -1132,12 +1132,16 @@
snprintf (buf, sizeof buf, "__asan_stack_malloc_%d",
use_after_return_class);
ret = init_one_libfunc (buf);
- rtx addr = convert_memory_address (ptr_mode, base);
- ret = emit_library_call_value (ret, NULL_RTX, LCT_NORMAL, ptr_mode, 2,
+ ret = emit_library_call_value (ret, NULL_RTX, LCT_NORMAL, ptr_mode, 1,
GEN_INT (asan_frame_size
+ base_align_bias),
- TYPE_MODE (pointer_sized_int_node),
- addr, ptr_mode);
+ TYPE_MODE (pointer_sized_int_node));
+ /* __asan_stack_malloc_[n] returns a pointer to fake stack if succeeded
+ and NULL otherwise. Check if RET value is NULL and jump over the
+ BASE reassignment in this case. Otherwise, reassign BASE to RET. */
+ int very_unlikely = REG_BR_PROB_BASE / 2000 - 1;
+ emit_cmp_and_jump_insns (ret, const0_rtx, EQ, NULL_RTX,
+ VOIDmode, 0, lab, very_unlikely);
ret = convert_memory_address (Pmode, ret);
emit_move_insn (base, ret);
emit_label (lab);
@@ -2470,6 +2474,8 @@
{
tree fn = builtin_decl_implicit (BUILT_IN_ASAN_INIT);
append_to_statement_list (build_call_expr (fn, 0), &asan_ctor_statements);
+ fn = builtin_decl_implicit (BUILT_IN_ASAN_VERSION_MISMATCH_CHECK);
+ append_to_statement_list (build_call_expr (fn, 0), &asan_ctor_statements);
}
FOR_EACH_DEFINED_VARIABLE (vnode)
if (TREE_ASM_WRITTEN (vnode->decl)
Index: gcc/sanitizer.def
===================================================================
--- gcc/sanitizer.def (revision 228817)
+++ gcc/sanitizer.def (working copy)
@@ -27,8 +27,11 @@
for other FEs by asan.c. */
/* Address Sanitizer */
-DEF_SANITIZER_BUILTIN(BUILT_IN_ASAN_INIT, "__asan_init_v4",
+DEF_SANITIZER_BUILTIN(BUILT_IN_ASAN_INIT, "__asan_init",
BT_FN_VOID, ATTR_NOTHROW_LEAF_LIST)
+DEF_SANITIZER_BUILTIN(BUILT_IN_ASAN_VERSION_MISMATCH_CHECK,
+ "__asan_version_mismatch_check_v6",
+ BT_FN_VOID, ATTR_NOTHROW_LEAF_LIST)
/* Do not reorder the BUILT_IN_ASAN_{REPORT,CHECK}* builtins, e.g. cfgcleanup.c
relies on this order. */
DEF_SANITIZER_BUILTIN(BUILT_IN_ASAN_REPORT_LOAD1, "__asan_report_load1",
Index: gcc/testsuite/g++.dg/asan/default-options-1.C
===================================================================
--- gcc/testsuite/g++.dg/asan/default-options-1.C (revision 228817)
+++ gcc/testsuite/g++.dg/asan/default-options-1.C (working copy)
@@ -12,4 +12,4 @@
return 0;
}
-// { dg-output "Using the defaults from __asan_default_options:.* foo=bar.*(\n|\r\n|\r)" }
+// { dg-output "WARNING: found 1 unrecognized flag\\(s\\):(\n|\r\n|\r).*foo(\n|\r\n|\r)" }
Index: config/bootstrap-asan.mk
===================================================================
--- config/bootstrap-asan.mk (revision 228817)
+++ config/bootstrap-asan.mk (working copy)
@@ -1,7 +1,7 @@
# This option enables -fsanitize=address for stage2 and stage3.
# Suppress LeakSanitizer in bootstrap.
-export ASAN_OPTIONS="detect_leaks=0"
+export LSAN_OPTIONS="detect_leaks=0"
STAGE2_CFLAGS += -fsanitize=address
STAGE3_CFLAGS += -fsanitize=address
