[PATCH] Allow inlining always_inline functions into no_sanitize_address ones with -fsanitize=address

[Jakub Jelinek]

Hi!

As mentioned in the PR, we refuse to inline with -fsanitize=address
no_sanitize_address functions into functions without that attribute,
which is good and has been requested in PR59600.
We also refuse to inline functions without that attribute into
no_sanitize_address functions, which is ok if it is optimization matter
only, we will just address sanitize the callee and not the caller.
But if such callee has always_inline attribute, this causes errors, and
e.g. means one can't use target intrinsics in functions with
no_sanitize_address attribute, as we refuse to inline any of those.

The following patch allows inlining always_inline functions in that
situation, the end result is that both the caller and callee which becomes
one function will not be sanitized (still errors if always_inline,
no_sanitize_address is being inlined into normal function, that is just user
error).

Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

2019-01-30  Jakub Jelinek  <ja...@redhat.com>

        PR sanitizer/89124
        * ipa-inline.c (sanitize_attrs_match_for_inline_p): Allow inlining
        always_inline callees into no_sanitize_address callers.

        * c-c++-common/asan/pr89124.c: New test.

--- gcc/ipa-inline.c.jj 2019-01-10 11:43:08.956466913 +0100
+++ gcc/ipa-inline.c    2019-01-30 22:21:57.319026848 +0100
@@ -264,6 +264,12 @@ sanitize_attrs_match_for_inline_p (const
   if (!caller || !callee)
     return true;
 
+  /* Allow inlining always_inline functions into no_sanitize_address
+     functions.  */
+  if (!sanitize_flags_p (SANITIZE_ADDRESS, caller)
+      && lookup_attribute ("always_inline", DECL_ATTRIBUTES (callee)))
+    return true;
+
   return ((sanitize_flags_p (SANITIZE_ADDRESS, caller)
           == sanitize_flags_p (SANITIZE_ADDRESS, callee))
          && (sanitize_flags_p (SANITIZE_POINTER_COMPARE, caller)
--- gcc/testsuite/c-c++-common/asan/pr89124.c.jj        2019-01-30 
22:23:27.018546142 +0100
+++ gcc/testsuite/c-c++-common/asan/pr89124.c   2019-01-30 22:23:05.568900221 
+0100
@@ -0,0 +1,14 @@
+/* PR sanitizer/89124 */
+/* { dg-do compile } */
+
+static int inline __attribute__ ((always_inline))
+foo (int x)
+{
+  return x + 1;
+}
+
+__attribute__ ((no_sanitize_address)) int
+bar (int x)
+{
+  return foo (x);
+}

        Jakub