@@ -63,6 +63,7 @@
#include "tm-constrs.h"
#include "rtl-iter.h"
#include "optabs-libfuncs.h"
+#include "gimplify.h"
/* This file should be included last. */
#include "target-def.h"
@@ -137,6 +138,7 @@ static tree arm_handle_isr_attribute (tree *, tree, tree, int, bool *);
static tree arm_handle_notshared_attribute (tree *, tree, tree, int, bool *);
#endif
static tree arm_handle_cmse_nonsecure_entry (tree *, tree, tree, int, bool *);
+static tree arm_handle_cmse_nonsecure_call (tree *, tree, tree, int, bool *);
static void arm_output_function_epilogue (FILE *, HOST_WIDE_INT);
static void arm_output_function_prologue (FILE *, HOST_WIDE_INT);
static int arm_comp_type_attributes (const_tree, const_tree);
@@ -348,6 +350,8 @@ static const struct attribute_spec arm_attribute_table[] =
/* ARMv8-M Security Extensions support. */
{ "cmse_nonsecure_entry", 0, 0, true, false, false,
arm_handle_cmse_nonsecure_entry, false },
+ { "cmse_nonsecure_call", 0, 0, true, false, false,
+ arm_handle_cmse_nonsecure_call, true },
{ NULL, 0, 0, false, false, false, NULL, false }
};
@@ -6753,6 +6757,78 @@ arm_handle_cmse_nonsecure_entry (tree *node, tree name,
return NULL_TREE;
}
+
+/* Called upon detection of the use of the cmse_nonsecure_call attribute, this
+ function will check whether the attribute is allowed here and will add the
+ attribute to the function type tree or otherwise issue a diagnostic. The
+ reason we check this at declaration time is to only allow the use of the
+ attribute with declarations of function pointers and not function
+ declarations. This function checks NODE is of the expected type and issues
+ diagnostics otherwise using NAME. If it is not of the expected type
+ *NO_ADD_ATTRS will be set to true. */
+
+static tree
+arm_handle_cmse_nonsecure_call (tree *node, tree name,
+ tree /* args */,
+ int /* flags */,
+ bool *no_add_attrs)
+{
+ tree decl = NULL_TREE, fntype = NULL_TREE;
+ tree main_variant, type;
+
+ if (!use_cmse)
+ {
+ *no_add_attrs = true;
+ warning (OPT_Wattributes, "%qE attribute ignored without -mcmse option.",
+ name);
+ return NULL_TREE;
+ }
+
+ if (TREE_CODE (*node) == VAR_DECL || TREE_CODE (*node) == TYPE_DECL)
+ {
+ decl = *node;
+ fntype = TREE_TYPE (decl);
+ }
+
+ while (fntype != NULL_TREE && TREE_CODE (fntype) == POINTER_TYPE)
+ fntype = TREE_TYPE (fntype);
+
+ if (!decl || TREE_CODE (fntype) != FUNCTION_TYPE)
+ {
+ warning (OPT_Wattributes, "%qE attribute only applies to base type of a "
+ "function pointer", name);
+ *no_add_attrs = true;
+ return NULL_TREE;
+ }
+
+ *no_add_attrs |= cmse_func_args_or_return_in_stack (NULL, name, fntype);
+
+ if (*no_add_attrs)
+ return NULL_TREE;
+
+ /* Prevent trees being shared among function types with and without
+ cmse_nonsecure_call attribute. */
+ type = TREE_TYPE (decl);
+
+ type = build_distinct_type_copy (type);
+ TREE_TYPE (decl) = type;
+ fntype = type;
+
+ while (TREE_CODE (fntype) != FUNCTION_TYPE)
+ {
+ type = fntype;
+ fntype = TREE_TYPE (fntype);
+ fntype = build_distinct_type_copy (fntype);
+ TREE_TYPE (type) = fntype;
+ }
+
+ /* Construct a type attribute and add it to the function type. */
+ tree attrs = tree_cons (get_identifier ("cmse_nonsecure_call"), NULL_TREE,
+ TYPE_ATTRIBUTES (fntype));
+ TYPE_ATTRIBUTES (fntype) = attrs;
+ return NULL_TREE;
+}
+
/* Return 0 if the attributes for two types are incompatible, 1 if they
are compatible, and 2 if they are nearly compatible (which causes a
warning to be generated). */
@@ -6793,6 +6869,14 @@ arm_comp_type_attributes (const_tree type1, const_tree type2)
if (l1 != l2)
return 0;
+ l1 = lookup_attribute ("cmse_nonsecure_call",
+ TYPE_ATTRIBUTES (type1)) != NULL;
+ l2 = lookup_attribute ("cmse_nonsecure_call",
+ TYPE_ATTRIBUTES (type2)) != NULL;
+
+ if (l1 != l2)
+ return 0;
+
return 1;
}
@@ -12622,8 +12622,8 @@ Security Extensions: Requiremenets on Development Tools Engineering
Specification, which can be found at
@uref{http://infocenter.arm.com/help/topic/com.arm.doc.ecm0359818/ECM0359818_armv8m_security_extensions_reqs_on_dev_tools_1_0.pdf}.
-As part of the Security Extensions GCC implements a new function attribute
-@code{cmse_nonsecure_entry}.
+As part of the Security Extensions GCC implements two new function attributes:
+@code{cmse_nonsecure_entry} and @code{cmse_nonsecure_call}.
As part of the Security Extensions GCC implements the intrinsics below. FPTR
is used here to mean any function pointer type.
new file mode 100644
@@ -0,0 +1,72 @@
+/* { dg-do compile } */
+/* { dg-options "-mcmse" } */
+
+int __attribute__ ((cmse_nonsecure_call)) (*ns_foo) (void);
+int (*s_bar) (void);
+int __attribute__ ((cmse_nonsecure_call)) (**ns_foo2) (void);
+int (**s_bar2) (void);
+
+typedef int __attribute__ ((cmse_nonsecure_call)) ns_foo_t (void);
+typedef int s_bar_t (void);
+typedef int __attribute__ ((cmse_nonsecure_call)) (* ns_foo_ptr) (void);
+typedef int (*s_bar_ptr) (void);
+
+int nonsecure0 (ns_foo_t * ns_foo_p)
+{
+ return ns_foo_p ();
+}
+
+int nonsecure1 (ns_foo_t ** ns_foo_p)
+{
+ return (*ns_foo_p) ();
+}
+
+int nonsecure2 (ns_foo_ptr ns_foo_p)
+{
+ return ns_foo_p ();
+}
+int nonsecure3 (ns_foo_ptr * ns_foo_p)
+{
+ return (*ns_foo_p) ();
+}
+
+int secure0 (s_bar_t * s_bar_p)
+{
+ return s_bar_p ();
+}
+
+int secure1 (s_bar_t ** s_bar_p)
+{
+ return (*s_bar_p) ();
+}
+
+int secure2 (s_bar_ptr s_bar_p)
+{
+ return s_bar_p ();
+}
+
+int secure3 (s_bar_ptr * s_bar_p)
+{
+ return (*s_bar_p) ();
+}
+
+int nonsecure4 (void)
+{
+ return ns_foo ();
+}
+
+int nonsecure5 (void)
+{
+ return (*ns_foo2) ();
+}
+
+int secure4 (void)
+{
+ return s_bar ();
+}
+
+int secure5 (void)
+{
+ return (*s_bar2) ();
+}
+/* { dg-final { scan-assembler-times "bl\\s+__gnu_cmse_nonsecure_call" 6 } } */
@@ -35,3 +35,11 @@ norf (struct span2 a) {}
void __attribute__ ((cmse_nonsecure_entry))
foo2 (long long a, int b, union test_union c) {} /* { dg-error "not available to functions with arguments passed on the stack" } */
+
+typedef void __attribute__ ((cmse_nonsecure_call)) bar2 (long long a, int b, long long c); /* { dg-error "not available to functions with arguments passed on the stack" } */
+
+typedef void __attribute__ ((cmse_nonsecure_call)) baz2 (long long a, int b, struct span c); /* { dg-error "not available to functions with arguments passed on the stack" } */
+
+typedef struct span __attribute__ ((cmse_nonsecure_call)) qux2 (void); /* { dg-error "not available to functions that return value on the stack" } */
+
+typedef void __attribute__ ((cmse_nonsecure_call)) norf2 (int a, ...); /* { dg-error "not available to functions with variable number of arguments" } */
@@ -19,9 +19,16 @@ baz (void)
return qux ();
}
+void __attribute__ ((cmse_nonsecure_call))
+quux (void) {} /* { dg-warning "attribute only applies to base type of a function pointer" } */
+
+int __attribute__ ((cmse_nonsecure_call)) norf; /* { dg-warning "attribute only applies to base type of a function pointer" } */
+
/* { dg-final { scan-assembler-times "bxns" 2 } } */
/* { dg-final { scan-assembler "foo:" } } */
/* { dg-final { scan-assembler "__acle_se_foo:" } } */
/* { dg-final { scan-assembler-not "__acle_se_bar:" } } */
/* { dg-final { scan-assembler "baz:" } } */
/* { dg-final { scan-assembler "__acle_se_baz:" } } */
+/* { dg-final { scan-assembler-not "__acle_se_quux:" } } */
+/* { dg-final { scan-assembler-not "__acle_se_norf:" } } */
Hi, I got a bug report against the old version of this patch and fixed it here. This had to do with GCC optimizations sharing types with and without the 'cmse_nonsecure_call' attribute. The patch now no longer sets the main variant, this didn't seem to do what I thought it did. Instead the patch now creates distinct type copies for every declared pointer that eventually points to the function type with the attribute, it will also create a distinct copy for the function type itself. Another change in this patch was to make 'arm_comp_type_attributes', the ARM implementation of TARGET_COMP_TYPE_ATTRIBUTES, deny compatibility between function types with the attribute and without. I added a test case to test the issue solved with these changes. *** gcc/ChangeLog *** 2016-11-xx Andre Vieira <andre.simoesdiasvieira@arm.com> Thomas Preud'homme <thomas.preudhomme@arm.com> * config/arm/arm.c (gimplify.h): New include. (arm_handle_cmse_nonsecure_call): New. (arm_attribute_table): Added cmse_nonsecure_call. (arm_comp_type_attributes): Deny compatibility of function types with without the cmse_nonsecure_call attribute. * doc/extend.texi (ARM ARMv8-M Security Extensions): New attribute. *** gcc/testsuite/ChangeLog *** 2016-11-xx Andre Vieira <andre.simoesdiasvieira@arm.com> Thomas Preud'homme <thomas.preudhomme@arm.com> * gcc.target/arm/cmse/cmse-3.c: Add tests. * gcc.target/arm/cmse/cmse-4.c: Add tests. * gcc.target/arm/cmse/cmse-15.c: New. Cheers, Andre