PR sanitizer/63839

	* asan.c (ATTR_CONST_NORETURN_NOTHROW_LEAF_LIST,
	ATTR_COLD_CONST_NORETURN_NOTHROW_LEAF_LIST): Define.
	* builtin-attrs.def (ATTR_COLD_CONST_NORETURN_NOTHROW_LEAF_LIST):
	Define.
	* builtins.c (fold_builtin_0): Don't include ubsan.h.  Don't
	instrument BUILT_IN_UNREACHABLE here.
	* sanitizer.def (BUILT_IN_UBSAN_HANDLE_BUILTIN_UNREACHABLE): Make
	const.
	* sanopt.c (pass_sanopt::execute): Instrument BUILT_IN_UNREACHABLE.
	* tree-ssa-ccp.c (optimize_unreachable): Bail out if
	SANITIZE_UNREACHABLE.
	* ubsan.c (ubsan_instrument_unreachable): Rewrite for GIMPLE.
	* ubsan.h (ubsan_instrument_unreachable): Adjust declaration.
testsuite/
	* c-c++-common/ubsan/pr63839.c: New test.
	* c-c++-common/ubsan/unreachable-2.c: New test.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@217553 138bc75d-0d04-0410-961f-82ee72b054a4

12 files changed, 106 insertions, 20 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 5e4a6686dd6..58efc772d66 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,20 @@
+2014-11-14  Marek Polacek  <polacek@redhat.com>
+
+	PR sanitizer/63839
+	* asan.c (ATTR_CONST_NORETURN_NOTHROW_LEAF_LIST,
+	ATTR_COLD_CONST_NORETURN_NOTHROW_LEAF_LIST): Define.
+	* builtin-attrs.def (ATTR_COLD_CONST_NORETURN_NOTHROW_LEAF_LIST):
+	Define.
+	* builtins.c (fold_builtin_0): Don't include ubsan.h.  Don't
+	instrument BUILT_IN_UNREACHABLE here.
+	* sanitizer.def (BUILT_IN_UBSAN_HANDLE_BUILTIN_UNREACHABLE): Make
+	const.
+	* sanopt.c (pass_sanopt::execute): Instrument BUILT_IN_UNREACHABLE.
+	* tree-ssa-ccp.c (optimize_unreachable): Bail out if
+	SANITIZE_UNREACHABLE.
+	* ubsan.c (ubsan_instrument_unreachable): Rewrite for GIMPLE.
+	* ubsan.h (ubsan_instrument_unreachable): Adjust declaration.
+
 2014-11-14  Alan Lawrence  <alan.lawrence@arm.com>
 
 	* config/rs6000/vector.md (vec_shl_<mode>): Remove.
diff --git a/gcc/asan.c b/gcc/asan.c
index 79dede71418..2961b4460de 100644
--- a/gcc/asan.c
+++ b/gcc/asan.c
@@ -2346,6 +2346,9 @@ initialize_sanitizer_builtins (void)
 #define ATTR_TMPURE_NOTHROW_LEAF_LIST ECF_TM_PURE | ATTR_NOTHROW_LEAF_LIST
 #undef ATTR_NORETURN_NOTHROW_LEAF_LIST
 #define ATTR_NORETURN_NOTHROW_LEAF_LIST ECF_NORETURN | ATTR_NOTHROW_LEAF_LIST
+#undef ATTR_CONST_NORETURN_NOTHROW_LEAF_LIST
+#define ATTR_CONST_NORETURN_NOTHROW_LEAF_LIST \
+  ECF_CONST | ATTR_NORETURN_NOTHROW_LEAF_LIST
 #undef ATTR_TMPURE_NORETURN_NOTHROW_LEAF_LIST
 #define ATTR_TMPURE_NORETURN_NOTHROW_LEAF_LIST \
   ECF_TM_PURE | ATTR_NORETURN_NOTHROW_LEAF_LIST
@@ -2355,6 +2358,9 @@ initialize_sanitizer_builtins (void)
 #undef ATTR_COLD_NORETURN_NOTHROW_LEAF_LIST
 #define ATTR_COLD_NORETURN_NOTHROW_LEAF_LIST \
   /* ECF_COLD missing */ ATTR_NORETURN_NOTHROW_LEAF_LIST
+#undef ATTR_COLD_CONST_NORETURN_NOTHROW_LEAF_LIST
+#define ATTR_COLD_CONST_NORETURN_NOTHROW_LEAF_LIST \
+  /* ECF_COLD missing */ ATTR_CONST_NORETURN_NOTHROW_LEAF_LIST
 #undef DEF_SANITIZER_BUILTIN
 #define DEF_SANITIZER_BUILTIN(ENUM, NAME, TYPE, ATTRS) \
   decl = add_builtin_function ("__builtin_" NAME, TYPE, ENUM,		\
diff --git a/gcc/builtin-attrs.def b/gcc/builtin-attrs.def
index 9c05a949039..c707367d4e7 100644
--- a/gcc/builtin-attrs.def
+++ b/gcc/builtin-attrs.def
@@ -145,6 +145,8 @@ DEF_ATTR_TREE_LIST (ATTR_SENTINEL_NOTHROW_LIST, ATTR_SENTINEL,	\
 			ATTR_NULL, ATTR_NOTHROW_LIST)
 DEF_ATTR_TREE_LIST (ATTR_SENTINEL_NOTHROW_LEAF_LIST, ATTR_SENTINEL,	\
 			ATTR_NULL, ATTR_NOTHROW_LEAF_LIST)
+DEF_ATTR_TREE_LIST (ATTR_COLD_CONST_NORETURN_NOTHROW_LEAF_LIST, ATTR_CONST,\
+			ATTR_NULL, ATTR_COLD_NORETURN_NOTHROW_LEAF_LIST)
 
 /* Functions whose pointer parameter(s) are all nonnull.  */
 DEF_ATTR_TREE_LIST (ATTR_NONNULL_LIST, ATTR_NONNULL, ATTR_NULL, ATTR_NULL)
diff --git a/gcc/builtins.c b/gcc/builtins.c
index 1cd65edb194..311c0e38279 100644
--- a/gcc/builtins.c
+++ b/gcc/builtins.c
@@ -64,7 +64,6 @@ along with GCC; see the file COPYING3.  If not see
 #include "diagnostic-core.h"
 #include "builtins.h"
 #include "asan.h"
-#include "ubsan.h"
 #include "cilk.h"
 #include "ipa-ref.h"
 #include "lto-streamer.h"
@@ -9803,14 +9802,6 @@ fold_builtin_0 (location_t loc, tree fndecl, bool ignore ATTRIBUTE_UNUSED)
     case BUILT_IN_CLASSIFY_TYPE:
       return fold_builtin_classify_type (NULL_TREE);
 
-    case BUILT_IN_UNREACHABLE:
-      if (flag_sanitize & SANITIZE_UNREACHABLE
-	  && (current_function_decl == NULL
-	      || !lookup_attribute ("no_sanitize_undefined",
-				    DECL_ATTRIBUTES (current_function_decl))))
-	return ubsan_instrument_unreachable (loc);
-      break;
-
     default:
       break;
     }
diff --git a/gcc/sanitizer.def b/gcc/sanitizer.def
index cddc5ea4935..3fc8c8396be 100644
--- a/gcc/sanitizer.def
+++ b/gcc/sanitizer.def
@@ -394,7 +394,7 @@ DEF_SANITIZER_BUILTIN(BUILT_IN_UBSAN_HANDLE_SHIFT_OUT_OF_BOUNDS,
 DEF_SANITIZER_BUILTIN(BUILT_IN_UBSAN_HANDLE_BUILTIN_UNREACHABLE,
 		      "__ubsan_handle_builtin_unreachable",
 		      BT_FN_VOID_PTR,
-		      ATTR_COLD_NORETURN_NOTHROW_LEAF_LIST)
+		      ATTR_COLD_CONST_NORETURN_NOTHROW_LEAF_LIST)
 DEF_SANITIZER_BUILTIN(BUILT_IN_UBSAN_HANDLE_MISSING_RETURN,
 		      "__ubsan_handle_missing_return",
 		      BT_FN_VOID_PTR,
diff --git a/gcc/sanopt.c b/gcc/sanopt.c
index 0fc032a7a30..fe2e42d121c 100644
--- a/gcc/sanopt.c
+++ b/gcc/sanopt.c
@@ -312,6 +312,21 @@ pass_sanopt::execute (function *fun)
 		  break;
 		}
 	    }
+	  else if (gimple_call_builtin_p (stmt, BUILT_IN_NORMAL))
+	    {
+	      tree callee = gimple_call_fndecl (stmt);
+	      switch (DECL_FUNCTION_CODE (callee))
+		{
+		case BUILT_IN_UNREACHABLE:
+		  if (flag_sanitize & SANITIZE_UNREACHABLE
+		      && !lookup_attribute ("no_sanitize_undefined",
+					    DECL_ATTRIBUTES (fun->decl)))
+		    no_next = ubsan_instrument_unreachable (&gsi);
+		  break;
+		default:
+		  break;
+		}
+	    }
 
 	  if (dump_file && (dump_flags & TDF_DETAILS))
 	    {
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 5ffb5d445b4..1d3ef947bf2 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2014-11-14  Marek Polacek  <polacek@redhat.com>
+
+	PR sanitizer/63839
+	* c-c++-common/ubsan/pr63839.c: New test.
+	* c-c++-common/ubsan/unreachable-2.c: New test.
+
 2014-11-14  Richard Biener  <rguenther@suse.de>
 
 	* gcc.c-torture/execute/shiftopt-1.c: XFAIL invalid parts.
diff --git a/gcc/testsuite/c-c++-common/ubsan/pr63839.c b/gcc/testsuite/c-c++-common/ubsan/pr63839.c
new file mode 100644
index 00000000000..e3933f7fe66
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/ubsan/pr63839.c
@@ -0,0 +1,23 @@
+/* { dg-do run } */
+/* { dg-options "-fsanitize=unreachable" } */
+/* { dg-skip-if "" { *-*-* } { "*" } { "-O2" } } */
+/* { dg-shouldfail "ubsan" } */
+
+static void __attribute__ ((noreturn))
+bar ()
+{
+} /* { dg-warning "function does return" } */
+
+void
+foo ()
+{
+  bar ();
+}
+
+int
+main (void)
+{
+  foo ();
+}
+
+/* { dg-output "execution reached a __builtin_unreachable\\(\\) call" } */
diff --git a/gcc/testsuite/c-c++-common/ubsan/unreachable-2.c b/gcc/testsuite/c-c++-common/ubsan/unreachable-2.c
new file mode 100644
index 00000000000..783ebc24913
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/ubsan/unreachable-2.c
@@ -0,0 +1,14 @@
+/* { dg-do run } */
+/* { dg-options "-fsanitize=unreachable" } */
+/* { dg-skip-if "" { *-*-* } { "*" } { "-O2" } } */
+/* { dg-shouldfail "ubsan" } */
+
+int e;
+
+int
+main (void)
+{
+  return e ? 0 : (__builtin_unreachable (), 1);
+}
+
+/* { dg-output "execution reached a __builtin_unreachable\\(\\) call" } */
diff --git a/gcc/tree-ssa-ccp.c b/gcc/tree-ssa-ccp.c
index 52d85036e1f..31ca0e120e3 100644
--- a/gcc/tree-ssa-ccp.c
+++ b/gcc/tree-ssa-ccp.c
@@ -2568,6 +2568,9 @@ optimize_unreachable (gimple_stmt_iterator i)
   edge e;
   bool ret;
 
+  if (flag_sanitize & SANITIZE_UNREACHABLE)
+    return false;
+
   for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
     {
       stmt = gsi_stmt (gsi);
diff --git a/gcc/ubsan.c b/gcc/ubsan.c
index 41cf546cde3..b5b1b924c67 100644
--- a/gcc/ubsan.c
+++ b/gcc/ubsan.c
@@ -588,17 +588,26 @@ ubsan_create_data (const char *name, int loccnt, const location_t *ploc, ...)
 /* Instrument the __builtin_unreachable call.  We just call the libubsan
    routine instead.  */
 
-tree
-ubsan_instrument_unreachable (location_t loc)
+bool
+ubsan_instrument_unreachable (gimple_stmt_iterator *gsi)
 {
-  if (flag_sanitize_undefined_trap_on_error)
-    return build_call_expr_loc (loc, builtin_decl_explicit (BUILT_IN_TRAP), 0);
+  gimple g;
+  location_t loc = gimple_location (gsi_stmt (*gsi));
 
-  initialize_sanitizer_builtins ();
-  tree data = ubsan_create_data ("__ubsan_unreachable_data", 1, &loc, NULL_TREE,
-				 NULL_TREE);
-  tree t = builtin_decl_explicit (BUILT_IN_UBSAN_HANDLE_BUILTIN_UNREACHABLE);
-  return build_call_expr_loc (loc, t, 1, build_fold_addr_expr_loc (loc, data));
+  if (flag_sanitize_undefined_trap_on_error)
+    g = gimple_build_call (builtin_decl_explicit (BUILT_IN_TRAP), 0);
+  else
+    {
+      tree data = ubsan_create_data ("__ubsan_unreachable_data", 1, &loc,
+				     NULL_TREE, NULL_TREE);
+      data = build_fold_addr_expr_loc (loc, data);
+      tree fn
+	= builtin_decl_explicit (BUILT_IN_UBSAN_HANDLE_BUILTIN_UNREACHABLE);
+      g = gimple_build_call (fn, 1, data);
+    }
+  gimple_set_location (g, loc);
+  gsi_replace (gsi, g, false);
+  return false;
 }
 
 /* Return true if T is a call to a libubsan routine.  */
diff --git a/gcc/ubsan.h b/gcc/ubsan.h
index 27c18eb00f8..dcdbb4fa4c9 100644
--- a/gcc/ubsan.h
+++ b/gcc/ubsan.h
@@ -41,7 +41,7 @@ enum ubsan_print_style {
 extern bool ubsan_expand_bounds_ifn (gimple_stmt_iterator *);
 extern bool ubsan_expand_null_ifn (gimple_stmt_iterator *);
 extern bool ubsan_expand_objsize_ifn (gimple_stmt_iterator *);
-extern tree ubsan_instrument_unreachable (location_t);
+extern bool ubsan_instrument_unreachable (gimple_stmt_iterator *);
 extern tree ubsan_create_data (const char *, int, const location_t *, ...);
 extern tree ubsan_type_descriptor (tree, enum ubsan_print_style = UBSAN_PRINT_NORMAL);
 extern tree ubsan_encode_value (tree, bool = false);