[gcc r14-9590] tree-optimization/111736 - avoid address sanitizing of __seg_gs

[Richard Biener]

https://gcc.gnu.org/g:134ef2a8cac1a5cc718739bd7d3b3472947c80d6

commit r14-9590-g134ef2a8cac1a5cc718739bd7d3b3472947c80d6
Author: Richard Biener <rguenther@suse.de>
Date:   Thu Mar 21 08:30:39 2024 +0100

    tree-optimization/111736 - avoid address sanitizing of __seg_gs
    
    The following more thoroughly avoids address sanitizing accesses
    to non-generic address-spaces.
    
            PR tree-optimization/111736
            * asan.cc (instrument_derefs): Do not instrument accesses
            to non-generic address-spaces.
    
            * gcc.target/i386/pr111736.c: New testcase.

Diff:
---
 gcc/asan.cc                              |  4 ++++
 gcc/testsuite/gcc.target/i386/pr111736.c | 23 +++++++++++++++++++++++
 2 files changed, 27 insertions(+)

diff --git a/gcc/asan.cc b/gcc/asan.cc
index cfe83106460..7f91cc616fc 100644
--- a/gcc/asan.cc
+++ b/gcc/asan.cc
@@ -2755,6 +2755,10 @@ instrument_derefs (gimple_stmt_iterator *iter, tree t,
   if (VAR_P (inner) && DECL_HARD_REGISTER (inner))
     return;
 
+  /* Accesses to non-generic address-spaces should not be instrumented.  */
+  if (!ADDR_SPACE_GENERIC_P (TYPE_ADDR_SPACE (TREE_TYPE (inner))))
+    return;
+
   poly_int64 decl_size;
   if ((VAR_P (inner)
        || (TREE_CODE (inner) == RESULT_DECL
diff --git a/gcc/testsuite/gcc.target/i386/pr111736.c b/gcc/testsuite/gcc.target/i386/pr111736.c
new file mode 100644
index 00000000000..231fdd07e80
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr111736.c
@@ -0,0 +1,23 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fsanitize=address" } */
+
+int __seg_gs m;
+
+int foo (void)
+{
+  return m;
+}
+
+extern int  __seg_gs n;
+
+int bar (void)
+{
+  return n;
+}
+
+int baz (int __seg_gs *o)
+{
+  return *o;
+}
+
+/* { dg-final { scan-assembler-not "asan_report_load" } } */