gfortran.h: Add bitmasks for different FPE traps.

	* gfortran.h: Add bitmasks for different FPE traps. Add fpe
	member to options_t.
	* invoke.texi: Document the new -ffpe-trap option.
	* lang.opt: Add -ffpe-trap option.
	* options.c (gfc_init_options): Initialize the FPE option.
	(gfc_handle_fpe_trap_option): New function to parse the argument
	of the -ffpe-trap option.
	(gfc_handle_option): Add case for -ffpe-trap.
	* trans-decl.c: Declare a tree for the set_fpe library function.
	(gfc_build_builtin_function_decls): Build this tree.
	(gfc_generate_function_code): Generate a call to set_fpe at
	the beginning of the main program.
	* trans.h: New tree for the set_fpe library function.

	* Makefile.am: Add fpu.c to the build process, and
	target-dependent code as fpu-target.h.
	* Makefile.in: Regenerate.
	* configure.ac: Add call to configure.host to set
	FPU_HOST_HEADER.
	* configure: Regenerate.
	* config.h.in: Regenerate.
	* aclocal.m4: Regenerate.
	* configure.host: New script to determine which host-dependent
	code should go in.
	* libgfortran.h: Add fpe option, remove previous fpu_ options.
	Add bitmasks for different FPE traps. Add prototype for set_fpu.
	* runtime/environ.c: Remove environment variables to control
	fpu behaviour.
	* runtime/fpu.c (set_fpe): New function for the front-end.
	* runtime/main.c (init): Set FPU state.
	* config: New directory to store host-dependent code.
	* config/fpu-387.h: New file with code handling the i387 FPU.
	* config/fpu-glibc.h: New file with code for glibc systems.
	* config/fpu-generic.h: Fallback for the most generic host. Issue
	warnings.

From-SVN: r105328

7 files changed, 112 insertions, 2 deletions

diff --git a/gcc/fortran/ChangeLog b/gcc/fortran/ChangeLog
index a02586f..91acbf2 100644
--- a/gcc/fortran/ChangeLog
+++ b/gcc/fortran/ChangeLog
@@ -1,3 +1,19 @@
+2005-10-12  Francois-Xavier Coudert  <coudert@clipper.ens.fr>
+
+	* gfortran.h: Add bitmasks for different FPE traps. Add fpe
+	member to options_t.
+	* invoke.texi: Document the new -ffpe-trap option.
+	* lang.opt: Add -ffpe-trap option.
+	* options.c (gfc_init_options): Initialize the FPE option.
+	(gfc_handle_fpe_trap_option): New function to parse the argument
+	of the -ffpe-trap option.
+	(gfc_handle_option): Add case for -ffpe-trap.
+	* trans-decl.c: Declare a tree for the set_fpe library function.
+	(gfc_build_builtin_function_decls): Build this tree.
+	(gfc_generate_function_code): Generate a call to set_fpe at
+	the beginning of the main program.
+	* trans.h: New tree for the set_fpe library function.
+
 2005-10-12  Paul Thomas  <pault@gcc.gnu.org>
 
 	PR fortran/20847
@@ -34,7 +50,7 @@
 
 2005-10-07  Erik Edelmann  <erik.edelmann@iki.fi>
 
-        PR 18568
+	PR 18568
 	* resolve.c (find_array_spec): Search through the list of
 	components in the symbol of the type instead of the symbol of the
 	variable.
diff --git a/gcc/fortran/gfortran.h b/gcc/fortran/gfortran.h
index 1923826..63b4b93 100644
--- a/gcc/fortran/gfortran.h
+++ b/gcc/fortran/gfortran.h
@@ -103,6 +103,15 @@ mstring;
 #define GFC_STD_F95_OBS		(1<<1)    /* Obsoleted in F95.  */
 #define GFC_STD_F77		(1<<0)    /* Up to and including F77.  */
 
+/* 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_PRECISION  (1<<5)
+
+
 /*************************** Enums *****************************/
 
 /* The author remains confused to this day about the convention of
@@ -1453,6 +1462,8 @@ typedef struct
 
   int q_kind;
 
+  int fpe;
+
   int warn_std;
   int allow_std;
   int warn_nonstd_intrinsics;
diff --git a/gcc/fortran/invoke.texi b/gcc/fortran/invoke.texi
index 847ab29..88e8eef 100644
--- a/gcc/fortran/invoke.texi
+++ b/gcc/fortran/invoke.texi
@@ -133,7 +133,7 @@ by type.  Explanations are in the following sections.
 @item Debugging Options
 @xref{Debugging Options,,Options for Debugging Your Program or GCC}.
 @gccoptlist{
--fdump-parse-tree}
+-fdump-parse-tree -ffpe-trap=@var{list}}
 
 @item Directory Options
 @xref{Directory Options,,Options for Directory Search}.
@@ -464,6 +464,22 @@ Output the internal parse tree before starting code generation.  Only
 really useful for debugging gfortran itself.
 @end table
 
+@table @gcctabopt
+@cindex -ffpe-trap=@var{list} option
+@cindex option, -ffpe-trap=@var{list}
+@item -ffpe-trap=@var{list}
+Specify a list of IEEE exceptions when a Floating Point Exception
+(FPE) should be raised.  On most systems, this will result in a SIGFPE
+signal being sent and the program being interrupted, producing a core
+file useful for debugging.  @var{list} is a (possibly empty) comma-separated
+list of the following IEEE exceptions: @samp{invalid} (invalid floating
+point operation, such as @code{sqrt(-1.0)}), @samp{zero} (division by
+zero), @samp{overflow} (overflow in a floating point operation),
+@samp{underflow} (underflow in a floating point operation),
+@samp{precision} (loss of precision during operation) and @samp{denormal}
+(operation produced a denormal denormal value).
+@end table
+
 @xref{Debugging Options,,Options for Debugging Your Program or GCC,
 gcc,Using the GNU Compiler Collection (GCC)}, for more information on
 debugging options.
diff --git a/gcc/fortran/lang.opt b/gcc/fortran/lang.opt
index ee0d61f..053cc3d 100644
--- a/gcc/fortran/lang.opt
+++ b/gcc/fortran/lang.opt
@@ -165,6 +165,10 @@ qkind=
 Fortran RejectNegative Joined UInteger
 -qkind=<n>	Set the kind for a real with the 'q' exponent to 'n'
 
+ffpe-trap=
+Fortran RejectNegative JoinedOrMissing
+-ffpe-trap=[..]	Stop on following floating point exceptions
+
 std=f95
 Fortran
 Conform to the ISO Fortran 95 standard
diff --git a/gcc/fortran/options.c b/gcc/fortran/options.c
index 48df674..95720bf 100644
--- a/gcc/fortran/options.c
+++ b/gcc/fortran/options.c
@@ -76,6 +76,8 @@ gfc_init_options (unsigned int argc ATTRIBUTE_UNUSED,
 
   gfc_option.q_kind = gfc_default_double_kind;
 
+  gfc_option.fpe = 0;
+
   flag_argument_noalias = 2;
   flag_errno_math = 0;
 
@@ -278,6 +280,41 @@ gfc_handle_module_path_options (const char *arg)
   strcat (gfc_option.module_dir, "/");
 }
 
+static void
+gfc_handle_fpe_trap_option (const char *arg)
+{
+  int result, pos = 0, n;
+  static const char * const exception[] = { "invalid", "denormal", "zero",
+                                            "overflow", "underflow",
+					    "precision", NULL };
+  static const int opt_exception[] = { GFC_FPE_INVALID, GFC_FPE_DENORMAL,
+				       GFC_FPE_ZERO, GFC_FPE_OVERFLOW,
+				       GFC_FPE_UNDERFLOW, GFC_FPE_PRECISION,
+				       0 };
+ 
+  while (*arg)
+    {
+      while (*arg == ',')
+	arg++;
+      while (arg[pos] && arg[pos] != ',')
+	pos++;
+      result = 0;
+      for (n = 0; exception[n] != NULL; n++)
+	{
+	  if (exception[n] && strncmp (exception[n], arg, pos) == 0)
+	    {
+	      gfc_option.fpe |= opt_exception[n];
+	      arg += pos;
+	      pos = 0;
+	      result = 1;
+	      break;
+	    }
+	}
+      if (! result)
+	gfc_fatal_error ("Argument to -ffpe-trap is not valid: %s", arg);
+    }
+}
+
 /* Handle command-line options.  Returns 0 if unrecognized, 1 if
    recognized and handled.  */
 int
@@ -440,6 +477,10 @@ gfc_handle_option (size_t scode, const char *arg, int value)
       gfc_handle_module_path_options (arg);
       break;
     
+    case OPT_ffpe_trap_:
+      gfc_handle_fpe_trap_option (arg);
+      break;
+
     case OPT_std_f95:
       gfc_option.allow_std = GFC_STD_F95_OBS | GFC_STD_F95 | GFC_STD_F77;
       gfc_option.warn_std = GFC_STD_F95_OBS;
diff --git a/gcc/fortran/trans-decl.c b/gcc/fortran/trans-decl.c
index 3f656dd..70e8e82 100644
--- a/gcc/fortran/trans-decl.c
+++ b/gcc/fortran/trans-decl.c
@@ -85,6 +85,7 @@ tree gfor_fndecl_stop_numeric;
 tree gfor_fndecl_stop_string;
 tree gfor_fndecl_select_string;
 tree gfor_fndecl_runtime_error;
+tree gfor_fndecl_set_fpe;
 tree gfor_fndecl_set_std;
 tree gfor_fndecl_in_pack;
 tree gfor_fndecl_in_unpack;
@@ -1934,6 +1935,7 @@ gfc_build_intrinsic_function_decls (void)
 void
 gfc_build_builtin_function_decls (void)
 {
+  tree gfc_c_int_type_node = gfc_get_int_type (gfc_c_int_kind);
   tree gfc_int4_type_node = gfc_get_int_type (4);
   tree gfc_int8_type_node = gfc_get_int_type (8);
   tree gfc_logical4_type_node = gfc_get_logical_type (4);
@@ -2018,6 +2020,10 @@ gfc_build_builtin_function_decls (void)
   /* The runtime_error function does not return.  */
   TREE_THIS_VOLATILE (gfor_fndecl_runtime_error) = 1;
 
+  gfor_fndecl_set_fpe =
+    gfc_build_library_function_decl (get_identifier (PREFIX("set_fpe")),
+				    void_type_node, 1, gfc_c_int_type_node);
+
   gfor_fndecl_set_std =
     gfc_build_library_function_decl (get_identifier (PREFIX("set_std")),
 				    void_type_node,
@@ -2455,6 +2461,21 @@ gfc_generate_function_code (gfc_namespace * ns)
       gfc_add_expr_to_block (&body, tmp);
     }
 
+  /* If this is the main program and a -ffpe-trap option was provided,
+     add a call to set_fpe so that the library will raise a FPE when
+     needed.  */
+  if (sym->attr.is_main_program && gfc_option.fpe != 0)
+    {
+      tree arglist, gfc_c_int_type_node;
+
+      gfc_c_int_type_node = gfc_get_int_type (gfc_c_int_kind);
+      arglist = gfc_chainon_list (NULL_TREE,
+				  build_int_cst (gfc_c_int_type_node,
+						 gfc_option.fpe));
+      tmp = gfc_build_function_call (gfor_fndecl_set_fpe, arglist);
+      gfc_add_expr_to_block (&body, tmp);
+    }
+
   if (TREE_TYPE (DECL_RESULT (fndecl)) != void_type_node
       && sym->attr.subroutine)
     {
diff --git a/gcc/fortran/trans.h b/gcc/fortran/trans.h
index e64640c..16d0a37 100644
--- a/gcc/fortran/trans.h
+++ b/gcc/fortran/trans.h
@@ -455,6 +455,7 @@ extern GTY(()) tree gfor_fndecl_stop_numeric;
 extern GTY(()) tree gfor_fndecl_stop_string;
 extern GTY(()) tree gfor_fndecl_select_string;
 extern GTY(()) tree gfor_fndecl_runtime_error;
+extern GTY(()) tree gfor_fndecl_set_fpe;
 extern GTY(()) tree gfor_fndecl_set_std;
 extern GTY(()) tree gfor_fndecl_in_pack;
 extern GTY(()) tree gfor_fndecl_in_unpack;