Added support for ARMV8-M Security Extension cmse_nonsecure_caller intrinsic

    gcc/ChangeLog:
    2016-12-02  Andre Vieira  <andre.simoesdiasvieira@arm.com>
		Thomas Preud'homme  <thomas.preudhomme@arm.com>

	* config/arm/arm-builtins.c (arm_builtins): Define
	ARM_BUILTIN_CMSE_NONSECURE_CALLER.
	(bdesc_2arg): Add line for cmse_nonsecure_caller.
	(arm_init_builtins): Handle cmse_nonsecure_caller.
	(arm_expand_builtin): Likewise.
	* config/arm/arm_cmse.h (cmse_nonsecure_caller): New.

    gcc/testsuite/ChangeLog:
    2016-12-02  Andre Vieira  <andre.simoesdiasvieira@arm.com>
		Thomas Preud'homme  <thomas.preudhomme@arm.com>

	* gcc.target/arm/cmse/cmse-1.c: Add test for
	cmse_nonsecure_caller.


Co-Authored-By: Thomas Preud'homme <thomas.preudhomme@arm.com>

From-SVN: r243193

gcc/ChangeLog

 2016-12-02  Andre Vieira  <andre.simoesdiasvieira@arm.com>
 	    Thomas Preud'homme  <thomas.preudhomme@arm.com>
 
+	* config/arm/arm-builtins.c (arm_builtins): Define
+	ARM_BUILTIN_CMSE_NONSECURE_CALLER.
+	(bdesc_2arg): Add line for cmse_nonsecure_caller.
+	(arm_init_builtins): Handle cmse_nonsecure_caller.
+	(arm_expand_builtin): Likewise.
+	* config/arm/arm_cmse.h (cmse_nonsecure_caller): New.
+
+2016-12-02  Andre Vieira  <andre.simoesdiasvieira@arm.com>
+	    Thomas Preud'homme  <thomas.preudhomme@arm.com>
+
 	* config/arm/arm.c (detect_cmse_nonsecure_call): New.
 	(cmse_nonsecure_call_clear_caller_saved): New.
 	(arm_reorg): Use cmse_nonsecure_call_clear_caller_saved.

gcc/config/arm/arm-builtins.c

@@ -528,6 +528,8 @@ enum arm_builtins
   ARM_BUILTIN_GET_FPSCR,
   ARM_BUILTIN_SET_FPSCR,
 
+  ARM_BUILTIN_CMSE_NONSECURE_CALLER,
+
 #undef CRYPTO1
 #undef CRYPTO2
 #undef CRYPTO3
@@ -1833,6 +1835,17 @@ arm_init_builtins (void)
 	= add_builtin_function ("__builtin_arm_stfscr", ftype_set_fpscr,
 				ARM_BUILTIN_SET_FPSCR, BUILT_IN_MD, NULL, NULL_TREE);
     }
+
+  if (use_cmse)
+    {
+      tree ftype_cmse_nonsecure_caller
+	= build_function_type_list (unsigned_type_node, NULL);
+      arm_builtin_decls[ARM_BUILTIN_CMSE_NONSECURE_CALLER]
+	= add_builtin_function ("__builtin_arm_cmse_nonsecure_caller",
+				ftype_cmse_nonsecure_caller,
+				ARM_BUILTIN_CMSE_NONSECURE_CALLER, BUILT_IN_MD,
+				NULL, NULL_TREE);
+    }
 }
 
 /* Return the ARM builtin for CODE.  */
@@ -2453,6 +2466,12 @@ arm_expand_builtin (tree exp,
       emit_insn (pat);
       return target;
 
+    case ARM_BUILTIN_CMSE_NONSECURE_CALLER:
+      target = gen_reg_rtx (SImode);
+      op0 = arm_return_addr (0, NULL_RTX);
+      emit_insn (gen_addsi3 (target, op0, const1_rtx));
+      return target;
+
     case ARM_BUILTIN_TEXTRMSB:
     case ARM_BUILTIN_TEXTRMUB:
     case ARM_BUILTIN_TEXTRMSH:

gcc/config/arm/arm_cmse.h

@@ -163,6 +163,13 @@ __attribute__ ((__always_inline__))
 cmse_TTAT (void *__p)
 __CMSE_TT_ASM (at)
 
+/* FIXME: diagnose use outside cmse_nonsecure_entry functions.  */
+__extension__ static __inline int __attribute__ ((__always_inline__))
+cmse_nonsecure_caller (void)
+{
+  return __builtin_arm_cmse_nonsecure_caller ();
+}
+
 #define CMSE_AU_NONSECURE	2
 #define CMSE_MPU_NONSECURE	16
 #define CMSE_NONSECURE		18

gcc/doc/extend.texi

@@ -12666,6 +12666,7 @@ cmse_address_info_t cmse_TTAT_fptr (FPTR)
 void * cmse_check_address_range (void *, size_t, int)
 typeof(p) cmse_nsfptr_create (FPTR p)
 intptr_t cmse_is_nsfptr (FPTR)
+int cmse_nonsecure_caller (void)
 @end smallexample
 
 @node AVR Built-in Functions

gcc/testsuite/ChangeLog

 2016-12-02  Andre Vieira  <andre.simoesdiasvieira@arm.com>
 	    Thomas Preud'homme  <thomas.preudhomme@arm.com>
 
+	* gcc.target/arm/cmse/cmse-1.c: Add test for
+	cmse_nonsecure_caller.
+
+2016-12-02  Andre Vieira  <andre.simoesdiasvieira@arm.com>
+	    Thomas Preud'homme  <thomas.preudhomme@arm.com>
+
 	* gcc.target/arm/cmse/cmse.exp: Run tests in mainline dir.
 	* gcc.target/arm/cmse/cmse-9.c: Added some extra tests.
 	* gcc.target/arm/cmse/cmse-14.c: New.

gcc/testsuite/gcc.target/arm/cmse/cmse-1.c

@@ -65,3 +65,42 @@ int foo (char * p)
 /* { dg-final { scan-assembler-times "ttat " 2 } } */
 /* { dg-final { scan-assembler-times "bl.cmse_check_address_range" 7 } } */
 /* { dg-final { scan-assembler-not "cmse_check_pointed_object" } } */
+
+int __attribute__ ((cmse_nonsecure_entry))
+baz (void)
+{
+  return cmse_nonsecure_caller ();
+}
+
+typedef int __attribute__ ((cmse_nonsecure_call)) (int_nsfunc_t) (void);
+
+int default_callback (void)
+{
+  return 0;
+}
+
+int_nsfunc_t * fp = (int_nsfunc_t *) default_callback;
+
+void __attribute__ ((cmse_nonsecure_entry))
+qux (int_nsfunc_t * callback)
+{
+  fp = cmse_nsfptr_create (callback);
+}
+
+int call_callback (void)
+{
+  if (cmse_is_nsfptr (fp))
+      return fp ();
+  else
+    return default_callback ();
+}
+/* { dg-final { scan-assembler "baz:" } } */
+/* { dg-final { scan-assembler "__acle_se_baz:" } } */
+/* { dg-final { scan-assembler "qux:" } } */
+/* { dg-final { scan-assembler "__acle_se_qux:" } } */
+/* { dg-final { scan-assembler-not "\tcmse_nonsecure_caller" } } */
+/* { dg-final { scan-rtl-dump "and.*reg.*const_int 1" expand } } */
+/* { dg-final { scan-assembler "bic" } } */
+/* { dg-final { scan-assembler "push\t\{r4, r5, r6" } } */
+/* { dg-final { scan-assembler "msr\tAPSR_nzcvq" } } */
+/* { dg-final { scan-assembler-times "bl\\s+__gnu_cmse_nonsecure_call" 1 } } */