re PR fortran/29383 (Fortran 2003/F95[TR15580:1999]: Floating point exception (IEEE) support)

	PR fortran/29383

gcc/fortran/
	* gfortran.h (gfc_simplify_ieee_selected_real_kind): New prototype.
	* libgfortran.h (GFC_FPE_*): Use simple integer values, valid in
	both C and Fortran.
	* expr.c (gfc_check_init_expr): Simplify IEEE_SELECTED_REAL_KIND.
	* simplify.c (gfc_simplify_ieee_selected_real_kind): New function.
	* module.c (mio_symbol): Keep track of symbols which came from
	intrinsic modules.
	(gfc_use_module): Keep track of the IEEE modules.
	* trans-decl.c (gfc_get_symbol_decl): Adjust code since
	we have new intrinsic modules.
	(gfc_build_builtin_function_decls): Build decls for
	ieee_procedure_entry and ieee_procedure_exit.
	(is_from_ieee_module, is_ieee_module_used, save_fp_state,
	restore_fp_state): New functions.
	(gfc_generate_function_code): Save and restore floating-point
	state on procedure entry/exit, when IEEE modules are used.
	* intrinsic.texi: Document the IEEE modules.

libgfortran/
	* configure.host: Add checks for IEEE support, rework priorities.
	* configure.ac: Define IEEE_SUPPORT, check for fpsetsticky and
	fpresetsticky.
	* configure: Regenerate.
	* Makefile.am: Build new ieee files, install IEEE_* modules.
	* Makefile.in: Regenerate.
	* gfortran.map (GFORTRAN_1.6): Add new symbols.
	* libgfortran.h (get_fpu_trap_exceptions, set_fpu_trap_exceptions,
	support_fpu_trap, set_fpu_except_flags, support_fpu_flag,
	support_fpu_rounding_mode, get_fpu_state, set_fpu_state): New
	prototypes.
	* config/fpu-*.h (get_fpu_trap_exceptions,
	set_fpu_trap_exceptions, support_fpu_trap, set_fpu_except_flags,
	support_fpu_flag, support_fpu_rounding_mode, get_fpu_state,
	set_fpu_state): New functions.
	* ieee/ieee_features.F90: New file.
	* ieee/ieee_exceptions.F90: New file.
	* ieee/ieee_arithmetic.F90: New file.
	* ieee/ieee_helper.c: New file.

gcc/testsuite/
	* lib/target-supports.exp (check_effective_target_fortran_ieee): 
	New function.
	* gfortran.dg/ieee/ieee.exp: New file.
	* gfortran.dg/ieee/ieee_1.F90: New file.
	* gfortran.dg/ieee/ieee_2.f90: New file.
	* gfortran.dg/ieee/ieee_3.f90: New file.
	* gfortran.dg/ieee/ieee_4.f90: New file.
	* gfortran.dg/ieee/ieee_5.f90: New file.
	* gfortran.dg/ieee/ieee_6.f90: New file.
	* gfortran.dg/ieee/ieee_7.f90: New file.
	* gfortran.dg/ieee/ieee_rounding_1.f90: New file.

From-SVN: r212102

8 files changed, 272 insertions, 16 deletions

diff --git a/gcc/fortran/ChangeLog b/gcc/fortran/ChangeLog
index f1ac532..a5f6f9d5 100644
--- a/gcc/fortran/ChangeLog
+++ b/gcc/fortran/ChangeLog
@@ -1,3 +1,24 @@
+2014-06-28  Francois-Xavier Coudert  <fxcoudert@gcc.gnu.org>
+
+	PR fortran/29383
+	* gfortran.h (gfc_simplify_ieee_selected_real_kind): New prototype.
+	* libgfortran.h (GFC_FPE_*): Use simple integer values, valid in
+	both C and Fortran.
+	* expr.c (gfc_check_init_expr): Simplify IEEE_SELECTED_REAL_KIND.
+	* simplify.c (gfc_simplify_ieee_selected_real_kind): New function.
+	* module.c (mio_symbol): Keep track of symbols which came from
+	intrinsic modules.
+	(gfc_use_module): Keep track of the IEEE modules.
+	* trans-decl.c (gfc_get_symbol_decl): Adjust code since
+	we have new intrinsic modules.
+	(gfc_build_builtin_function_decls): Build decls for
+	ieee_procedure_entry and ieee_procedure_exit.
+	(is_from_ieee_module, is_ieee_module_used, save_fp_state,
+	restore_fp_state): New functions.
+	(gfc_generate_function_code): Save and restore floating-point
+	state on procedure entry/exit, when IEEE modules are used.
+	* intrinsic.texi: Document the IEEE modules.
+
 2014-06-25  Tobias Burnus  <burnus@net-b.de>
 
 	* interface.c (check_intents): Fix diagnostic with
diff --git a/gcc/fortran/expr.c b/gcc/fortran/expr.c
index feb089e..3e3a664 100644
--- a/gcc/fortran/expr.c
+++ b/gcc/fortran/expr.c
@@ -2460,9 +2460,23 @@ gfc_check_init_expr (gfc_expr *e)
 
       {
 	gfc_intrinsic_sym* isym;
-	gfc_symbol* sym;
+	gfc_symbol* sym = e->symtree->n.sym;
+
+	/* Special case for IEEE_SELECTED_REAL_KIND from the intrinsic
+	   module IEEE_ARITHMETIC, which is allowed in initialization
+	   expressions.  */
+	if (!strcmp(sym->name, "ieee_selected_real_kind")
+	    && sym->from_intmod == INTMOD_IEEE_ARITHMETIC)
+	  {
+	    gfc_expr *new_expr = gfc_simplify_ieee_selected_real_kind (e);
+	    if (new_expr)
+	      {
+		gfc_replace_expr (e, new_expr);
+		t = true;
+		break;
+	      }
+	  }
 
-	sym = e->symtree->n.sym;
 	if (!gfc_is_intrinsic (sym, 0, e->where)
 	    || (m = gfc_intrinsic_func_interface (e, 0)) != MATCH_YES)
 	  {
diff --git a/gcc/fortran/gfortran.h b/gcc/fortran/gfortran.h
index 1c4638f..3481319 100644
--- a/gcc/fortran/gfortran.h
+++ b/gcc/fortran/gfortran.h
@@ -678,7 +678,8 @@ iso_c_binding_symbol;
 
 typedef enum
 {
-  INTMOD_NONE = 0, INTMOD_ISO_FORTRAN_ENV, INTMOD_ISO_C_BINDING
+  INTMOD_NONE = 0, INTMOD_ISO_FORTRAN_ENV, INTMOD_ISO_C_BINDING,
+  INTMOD_IEEE_FEATURES, INTMOD_IEEE_EXCEPTIONS, INTMOD_IEEE_ARITHMETIC
 }
 intmod_id;
 
@@ -2870,6 +2871,8 @@ gfc_formal_arglist *gfc_sym_get_dummy_args (gfc_symbol *);
 /* intrinsic.c -- true if working in an init-expr, false otherwise.  */
 extern bool gfc_init_expr_flag;
 
+gfc_expr *gfc_simplify_ieee_selected_real_kind (gfc_expr *);
+
 /* Given a symbol that we have decided is intrinsic, mark it as such
    by placing it into a special module that is otherwise impossible to
    read or write.  */
diff --git a/gcc/fortran/intrinsic.texi b/gcc/fortran/intrinsic.texi
index 202063f..87f6478 100644
--- a/gcc/fortran/intrinsic.texi
+++ b/gcc/fortran/intrinsic.texi
@@ -13155,6 +13155,7 @@ Fortran 95 elemental function: @ref{IEOR}
 @menu
 * ISO_FORTRAN_ENV::
 * ISO_C_BINDING::
+* IEEE modules::
 * OpenMP Modules OMP_LIB and OMP_LIB_KINDS::
 @end menu
 
@@ -13366,6 +13367,35 @@ Moreover, the following two named constants are defined:
 
 Both are equivalent to the value @code{NULL} in C.
 
+
+
+@node IEEE modules
+@section IEEE modules: @code{IEEE_EXCEPTIONS}, @code{IEEE_ARITHMETIC}, and @code{IEEE_FEATURES}
+@table @asis
+@item @emph{Standard}:
+Fortran 2003 and later
+@end table
+
+The @code{IEEE_EXCEPTIONS}, @code{IEEE_ARITHMETIC}, and @code{IEEE_FEATURES}
+intrinsic modules provide support for exceptions and IEEE arithmetic, as
+defined in Fortran 2003 and later standards, and the IEC 60559:1989 standard
+(@emph{Binary floating-point arithmetic for microprocessor systems}). These
+modules are only provided on the following supported platforms:
+
+@itemize @bullet
+@item i386 and x86_64 processors
+@item platforms which use the GNU C Library (glibc)
+@item platforms with support for SysV/386 routines for floating point
+interface (including Solaris and BSDs)
+@item platforms with the AIX OS
+@end itemize
+
+For full compliance with the Fortran standards, code using the
+@code{IEEE_EXCEPTIONS} or @code{IEEE_ARITHMETIC} modules should be compiled
+with the following options: @code{-fno-unsafe-math-optimizations
+-frounding-math -fsignaling-nans}.
+
+
 @node OpenMP Modules OMP_LIB and OMP_LIB_KINDS
 @section OpenMP Modules @code{OMP_LIB} and @code{OMP_LIB_KINDS}
 @table @asis
diff --git a/gcc/fortran/libgfortran.h b/gcc/fortran/libgfortran.h
index 230b638..1f8616f 100644
--- a/gcc/fortran/libgfortran.h
+++ b/gcc/fortran/libgfortran.h
@@ -35,13 +35,14 @@ along with GCC; see the file COPYING3.  If not see
 					   obsolescent in later standards.  */
 
 
-/* Bitmasks for the various FPE that can be enabled.  */
-#define GFC_FPE_INVALID    (1<<0)
-#define GFC_FPE_DENORMAL   (1<<1)
-#define GFC_FPE_ZERO       (1<<2)
-#define GFC_FPE_OVERFLOW   (1<<3)
-#define GFC_FPE_UNDERFLOW  (1<<4)
-#define GFC_FPE_INEXACT    (1<<5)
+/* Bitmasks for the various FPE that can be enabled.  These need to be straight integers
+   e.g., 8 instead of (1<<3), because they will be included in Fortran source.  */
+#define GFC_FPE_INVALID      1
+#define GFC_FPE_DENORMAL     2
+#define GFC_FPE_ZERO         4
+#define GFC_FPE_OVERFLOW     8
+#define GFC_FPE_UNDERFLOW   16
+#define GFC_FPE_INEXACT     32
 
 /* Defines for floating-point rounding modes.  */
 #define GFC_FPE_DOWNWARD   1
@@ -49,6 +50,10 @@ along with GCC; see the file COPYING3.  If not see
 #define GFC_FPE_TOWARDZERO 3
 #define GFC_FPE_UPWARD     4
 
+/* Size of the buffer required to store FPU state for any target.
+   In particular, this has to be larger than fenv_t on all glibc targets.
+   Currently, the winner is x86_64 with 32 bytes.  */
+#define GFC_FPE_STATE_BUFFER_SIZE 32
 
 /* Bitmasks for the various runtime checks that can be enabled.  */
 #define GFC_RTCHECK_BOUNDS      (1<<0)
diff --git a/gcc/fortran/module.c b/gcc/fortran/module.c
index ec67960..bd7da1c 100644
--- a/gcc/fortran/module.c
+++ b/gcc/fortran/module.c
@@ -190,6 +190,9 @@ static gzFile module_fp;
 static const char *module_name;
 static gfc_use_list *module_list;
 
+/* If we're reading an intrinsic module, this is its ID.  */
+static intmod_id current_intmod;
+
 /* Content of module.  */
 static char* module_content;
 
@@ -4096,7 +4099,10 @@ mio_symbol (gfc_symbol *sym)
   else
     {
       mio_integer (&intmod);
-      sym->from_intmod = (intmod_id) intmod;
+      if (current_intmod)
+	sym->from_intmod = current_intmod;
+      else
+	sym->from_intmod = (intmod_id) intmod;
     }
   
   mio_integer (&(sym->intmod_sym_id));
@@ -6733,6 +6739,7 @@ gfc_use_module (gfc_use_list *module)
   module_name = module->module_name;
   gfc_rename_list = module->rename;
   only_flag = module->only_flag;
+  current_intmod = INTMOD_NONE;
 
   filename = XALLOCAVEC (char, strlen (module_name) + strlen (MODULE_EXTENSION)
 			       + 1);
@@ -6777,6 +6784,26 @@ gfc_use_module (gfc_use_list *module)
       if (module_fp == NULL && module->intrinsic)
 	gfc_fatal_error ("Can't find an intrinsic module named '%s' at %C",
 			 module_name);
+
+      /* Check for the IEEE modules, so we can mark their symbols
+	 accordingly when we read them.  */
+      if (strcmp (module_name, "ieee_features") == 0
+	  && gfc_notify_std (GFC_STD_F2003, "IEEE_FEATURES module at %C"))
+	{
+	  current_intmod = INTMOD_IEEE_FEATURES;
+	}
+      else if (strcmp (module_name, "ieee_exceptions") == 0
+	       && gfc_notify_std (GFC_STD_F2003,
+				  "IEEE_EXCEPTIONS module at %C"))
+	{
+	  current_intmod = INTMOD_IEEE_EXCEPTIONS;
+	}
+      else if (strcmp (module_name, "ieee_arithmetic") == 0
+	       && gfc_notify_std (GFC_STD_F2003,
+				  "IEEE_ARITHMETIC module at %C"))
+	{
+	  current_intmod = INTMOD_IEEE_ARITHMETIC;
+	}
     }
 
   if (module_fp == NULL)
diff --git a/gcc/fortran/simplify.c b/gcc/fortran/simplify.c
index d18bc08..60d8593 100644
--- a/gcc/fortran/simplify.c
+++ b/gcc/fortran/simplify.c
@@ -5460,12 +5460,13 @@ gfc_simplify_selected_real_kind (gfc_expr *p, gfc_expr *q, gfc_expr *rdx)
       if (gfc_real_kinds[i].range >= range)
 	found_range = 1;
 
-      if (gfc_real_kinds[i].radix >= radix)
+      if (radix == 0 || gfc_real_kinds[i].radix == radix)
 	found_radix = 1;
 
       if (gfc_real_kinds[i].precision >= precision
 	  && gfc_real_kinds[i].range >= range
-	  && gfc_real_kinds[i].radix >= radix && gfc_real_kinds[i].kind < kind)
+	  && (radix == 0 || gfc_real_kinds[i].radix == radix)
+	  && gfc_real_kinds[i].kind < kind)
 	kind = gfc_real_kinds[i].kind;
     }
 
@@ -5488,6 +5489,87 @@ gfc_simplify_selected_real_kind (gfc_expr *p, gfc_expr *q, gfc_expr *rdx)
 
 
 gfc_expr *
+gfc_simplify_ieee_selected_real_kind (gfc_expr *expr)
+{
+  gfc_actual_arglist *arg = expr->value.function.actual;
+  gfc_expr *p = arg->expr, *r = arg->next->expr,
+	   *rad = arg->next->next->expr;
+  int precision, range, radix, res;
+  int found_precision, found_range, found_radix, i;
+
+  if (p)
+  {
+    if (p->expr_type != EXPR_CONSTANT
+	|| gfc_extract_int (p, &precision) != NULL)
+      return NULL;
+  }
+  else
+    precision = 0;
+
+  if (r)
+  {
+    if (r->expr_type != EXPR_CONSTANT
+	|| gfc_extract_int (r, &range) != NULL)
+      return NULL;
+  }
+  else
+    range = 0;
+
+  if (rad)
+  {
+    if (rad->expr_type != EXPR_CONSTANT
+	|| gfc_extract_int (rad, &radix) != NULL)
+      return NULL;
+  }
+  else
+    radix = 0;
+
+  res = INT_MAX;
+  found_precision = 0;
+  found_range = 0;
+  found_radix = 0;
+
+  for (i = 0; gfc_real_kinds[i].kind != 0; i++)
+    {
+      /* We only support the target's float and double types.  */
+      if (!gfc_real_kinds[i].c_float && !gfc_real_kinds[i].c_double)
+	continue;
+
+      if (gfc_real_kinds[i].precision >= precision)
+	found_precision = 1;
+
+      if (gfc_real_kinds[i].range >= range)
+	found_range = 1;
+
+      if (radix == 0 || gfc_real_kinds[i].radix == radix)
+	found_radix = 1;
+
+      if (gfc_real_kinds[i].precision >= precision
+	  && gfc_real_kinds[i].range >= range
+	  && (radix == 0 || gfc_real_kinds[i].radix == radix)
+	  && gfc_real_kinds[i].kind < res)
+	res = gfc_real_kinds[i].kind;
+    }
+
+  if (res == INT_MAX)
+    {
+      if (found_radix && found_range && !found_precision)
+	res = -1;
+      else if (found_radix && found_precision && !found_range)
+	res = -2;
+      else if (found_radix && !found_precision && !found_range)
+	res = -3;
+      else if (found_radix)
+	res = -4;
+      else
+	res = -5;
+    }
+
+  return gfc_get_int_expr (gfc_default_integer_kind, &expr->where, res);
+}
+
+
+gfc_expr *
 gfc_simplify_set_exponent (gfc_expr *x, gfc_expr *i)
 {
   gfc_expr *result;
diff --git a/gcc/fortran/trans-decl.c b/gcc/fortran/trans-decl.c
index 291dd1f..cbcd52d 100644
--- a/gcc/fortran/trans-decl.c
+++ b/gcc/fortran/trans-decl.c
@@ -90,6 +90,9 @@ static stmtblock_t caf_init_block;
 tree gfc_static_ctors;
 
 
+/* Whether we've seen a symbol from an IEEE module in the namespace.  */
+static int seen_ieee_symbol;
+
 /* Function declarations for builtin library functions.  */
 
 tree gfor_fndecl_pause_numeric;
@@ -118,6 +121,8 @@ tree gfor_fndecl_in_unpack;
 tree gfor_fndecl_associated;
 tree gfor_fndecl_system_clock4;
 tree gfor_fndecl_system_clock8;
+tree gfor_fndecl_ieee_procedure_entry;
+tree gfor_fndecl_ieee_procedure_exit;
 
 
 /* Coarray run-time library function decls.  */
@@ -1376,8 +1381,9 @@ gfc_get_symbol_decl (gfc_symbol * sym)
 
   /* Special case for array-valued named constants from intrinsic
      procedures; those are inlined.  */
-  if (sym->attr.use_assoc && sym->from_intmod
-      && sym->attr.flavor == FL_PARAMETER)
+  if (sym->attr.use_assoc && sym->attr.flavor == FL_PARAMETER
+      && (sym->from_intmod == INTMOD_ISO_FORTRAN_ENV
+	  || sym->from_intmod == INTMOD_ISO_C_BINDING))
     intrinsic_array_parameter = true;
 
   /* If use associated compilation, use the module
@@ -3269,6 +3275,14 @@ gfc_build_builtin_function_decls (void)
 	get_identifier (PREFIX("set_fpe")),
 	void_type_node, 1, integer_type_node);
 
+  gfor_fndecl_ieee_procedure_entry = gfc_build_library_function_decl (
+	get_identifier (PREFIX("ieee_procedure_entry")),
+	void_type_node, 1, pvoid_type_node);
+
+  gfor_fndecl_ieee_procedure_exit = gfc_build_library_function_decl (
+	get_identifier (PREFIX("ieee_procedure_exit")),
+	void_type_node, 1, pvoid_type_node);
+
   /* Keep the array dimension in sync with the call, later in this file.  */
   gfor_fndecl_set_options = gfc_build_library_function_decl_with_spec (
 	get_identifier (PREFIX("set_options")), "..R",
@@ -5530,6 +5544,55 @@ gfc_generate_return (void)
 }
 
 
+static void
+is_from_ieee_module (gfc_symbol *sym)
+{
+  if (sym->from_intmod == INTMOD_IEEE_FEATURES
+      || sym->from_intmod == INTMOD_IEEE_EXCEPTIONS
+      || sym->from_intmod == INTMOD_IEEE_ARITHMETIC)
+    seen_ieee_symbol = 1;
+}
+
+
+static int
+is_ieee_module_used (gfc_namespace *ns)
+{
+  seen_ieee_symbol = 0;
+  gfc_traverse_ns (ns, is_from_ieee_module);
+  return seen_ieee_symbol;
+}
+
+
+static tree
+save_fp_state (stmtblock_t *block)
+{
+  tree type, fpstate, tmp;
+
+  type = build_array_type (char_type_node,
+	                   build_range_type (size_type_node, size_zero_node,
+					     size_int (32)));
+  fpstate = gfc_create_var (type, "fpstate");
+  fpstate = gfc_build_addr_expr (pvoid_type_node, fpstate);
+
+  tmp = build_call_expr_loc (input_location, gfor_fndecl_ieee_procedure_entry,
+			     1, fpstate);
+  gfc_add_expr_to_block (block, tmp);
+
+  return fpstate;
+}
+
+
+static void
+restore_fp_state (stmtblock_t *block, tree fpstate)
+{
+  tree tmp;
+
+  tmp = build_call_expr_loc (input_location, gfor_fndecl_ieee_procedure_exit,
+			     1, fpstate);
+  gfc_add_expr_to_block (block, tmp);
+}
+
+
 /* Generate code for a function.  */
 
 void
@@ -5539,13 +5602,14 @@ gfc_generate_function_code (gfc_namespace * ns)
   tree old_context;
   tree decl;
   tree tmp;
+  tree fpstate = NULL_TREE;
   stmtblock_t init, cleanup;
   stmtblock_t body;
   gfc_wrapped_block try_block;
   tree recurcheckvar = NULL_TREE;
   gfc_symbol *sym;
   gfc_symbol *previous_procedure_symbol;
-  int rank;
+  int rank, ieee;
   bool is_recursive;
 
   sym = ns->proc_name;
@@ -5636,6 +5700,12 @@ gfc_generate_function_code (gfc_namespace * ns)
       free (msg);
     }
 
+  /* Check if an IEEE module is used in the procedure.  If so, save
+     the floating point state.  */
+  ieee = is_ieee_module_used (ns);
+  if (ieee)
+    fpstate = save_fp_state (&init);
+
   /* Now generate the code for the body of this function.  */
   gfc_init_block (&body);
 
@@ -5719,6 +5789,10 @@ gfc_generate_function_code (gfc_namespace * ns)
       recurcheckvar = NULL;
     }
 
+  /* If IEEE modules are loaded, restore the floating-point state.  */
+  if (ieee)
+    restore_fp_state (&cleanup, fpstate);
+
   /* Finish the function body and add init and cleanup code.  */
   tmp = gfc_finish_block (&body);
   gfc_start_wrapped_block (&try_block, tmp);