[PATCH] ASAN: do not rewrite param for DECL_NOT_GIMPLE_REG_P.

[Martin Liška]

Hi.

Starting from r11-165-geb72dc663e9070b2 we should not rewrite parameters that
have DECL_NOT_GIMPLE_REG_P set to true.

Patch can bootstrap on x86_64-linux-gnu and survives regression tests.

Ready to be installed?
Thanks,
Martin

gcc/ChangeLog:

2020-05-11  Martin Liska  <mli...@suse.cz>

        PR sanitizer/95033
        * sanopt.c (sanitize_rewrite_addressable_params):
        Do not rewrite for DECL_NOT_GIMPLE_REG_P.

gcc/testsuite/ChangeLog:

2020-05-11  Martin Liska  <mli...@suse.cz>

        PR sanitizer/95033
        * g++.dg/asan/function-argument-4.C: New test.
        * gcc.dg/asan/pr95033.c: New test.
---
 gcc/sanopt.c                                  |  1 +
 .../g++.dg/asan/function-argument-4.C         | 26 +++++++++++++++++++
 gcc/testsuite/gcc.dg/asan/pr95033.c           | 13 ++++++++++
 3 files changed, 40 insertions(+)
 create mode 100644 gcc/testsuite/g++.dg/asan/function-argument-4.C
 create mode 100644 gcc/testsuite/gcc.dg/asan/pr95033.c



diff --git a/gcc/sanopt.c b/gcc/sanopt.c
index 86180e32c7e..28a63442f4d 100644
--- a/gcc/sanopt.c
+++ b/gcc/sanopt.c
@@ -1155,6 +1155,7 @@ sanitize_rewrite_addressable_params (function *fun)
       if (TREE_ADDRESSABLE (arg)
 	  && !TREE_ADDRESSABLE (type)
 	  && !TREE_THIS_VOLATILE (arg)
+	  && !DECL_NOT_GIMPLE_REG_P (arg)
 	  && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST)
 	{
 	  TREE_ADDRESSABLE (arg) = 0;
diff --git a/gcc/testsuite/g++.dg/asan/function-argument-4.C b/gcc/testsuite/g++.dg/asan/function-argument-4.C
new file mode 100644
index 00000000000..cec1f1d788f
--- /dev/null
+++ b/gcc/testsuite/g++.dg/asan/function-argument-4.C
@@ -0,0 +1,26 @@
+// { dg-do run }
+// { dg-shouldfail "asan" }
+
+#include <complex.h>
+
+static __attribute__ ((noinline)) long double
+goo (long double _Complex *a)
+{
+  return crealf(*(volatile _Complex long double *)a);
+}
+
+__attribute__ ((noinline)) float
+foo (float _Complex arg)
+{
+  return goo ((long double _Complex *)&arg);
+}
+
+int
+main ()
+{
+  return foo (3 + 2 * I);
+}
+
+// { dg-output "ERROR: AddressSanitizer: stack-buffer-overflow on address.*(\n|\r\n|\r)" }
+// { dg-output "READ of size \[0-9\]* at.*" }
+// { dg-output ".*'arg' \\(line 13\\) <== Memory access at offset \[0-9\]* partially overflows this variable.*" }
diff --git a/gcc/testsuite/gcc.dg/asan/pr95033.c b/gcc/testsuite/gcc.dg/asan/pr95033.c
new file mode 100644
index 00000000000..1228b7edcdb
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/asan/pr95033.c
@@ -0,0 +1,13 @@
+/* PR sanitizer/95033 */
+/* { dg-do compile } */
+/* { dg-options "-fsanitize=address" } */
+
+struct a
+{
+  int b;
+};
+
+struct a c(_Complex d)
+{
+  return *(struct a *)&d;
+}