The attached patch implements the RANDOM_INIT intrinsic
subroutine specified in Fortran 2018. I have had this
patch in my local tree for the last 5+ months. Now that
8.1 is out, it is time to submit it. It has been built
and regression tested on x86_64-*-freebsd. OK to commit?
Note, I have only tested with -fcoarray=single as I don't
have OpenCoarray set up to build with trunk. Testing with
OpenCoarray is encouraged.
2018-05-28 Steven G. Kargl <ka...@gcc.gnu.org>
* check.c (gfc_check_random_init): New function. Check arguments of
RANDOM_INIT.
* gfortran.h (GFC_ISYM_RANDOM_INIT): New enum token.
* intrinsic.c (add_subroutines): Add RANDOM_INIT to list of
subroutines.
* intrinsic.h: Add prototypes for gfc_check_random_init and
gfc_resolve_random_init
* intrinsic.texi: Document new intrinsic subprogram.
* iresolve.c (gfc_resolve_random_init): Resolve routine name.
* trans-decl.c: Declare gfor_fndecl_random_init
* trans-intrinsic.c (conv_intrinsic_random_init): New function.
Translate call to RANDOM_INIT.
(gfc_conv_intrinsic_subroutine): Call it.
* trans.h: Declare gfor_fndecl_random_init
2018-05-28 Steven G. Kargl <ka...@gcc.gnu.org>
* gfortran.dg/random_init_1.f90: New test.
* gfortran.dg/random_init_2.f90: New test.
* gfortran.dg/random_init_3.f90: New test.
* gfortran.dg/random_init_4.f90: New test.
* gfortran.dg/random_init_5.f90: New test.
* gfortran.dg/random_init_6.f90: New test.
2018-05-28 Steven G. Kargl <ka...@gcc.gnu.org>
* libgfortran/Makefile.am: Add random_init.f90 to build.
* libgfortran/Makefile.in: Regenerated.
* libgfortran/gfortran.map: Expose symbol for _gfortran_random_init.
* libgfortran/intrinsics/random_init.f90: Implementation.
--
Steve
Index: gcc/fortran/check.c
===================================================================
--- gcc/fortran/check.c (revision 256953)
+++ gcc/fortran/check.c (working copy)
@@ -5744,6 +5744,27 @@ gfc_check_mvbits (gfc_expr *from, gfc_expr *frompos, g
}
+/* Check the arguments for RANDOM_INIT. */
+
+bool
+gfc_check_random_init (gfc_expr *repeatable, gfc_expr *image_distinct)
+{
+ if (!type_check (repeatable, 0, BT_LOGICAL))
+ return false;
+
+ if (!scalar_check (repeatable, 0))
+ return false;
+
+ if (!type_check (image_distinct, 1, BT_LOGICAL))
+ return false;
+
+ if (!scalar_check (image_distinct, 1))
+ return false;
+
+ return true;
+}
+
+
bool
gfc_check_random_number (gfc_expr *harvest)
{
Index: gcc/fortran/gfortran.h
===================================================================
--- gcc/fortran/gfortran.h (revision 256953)
+++ gcc/fortran/gfortran.h (working copy)
@@ -551,6 +551,7 @@ enum gfc_isym_id
GFC_ISYM_PRODUCT,
GFC_ISYM_RADIX,
GFC_ISYM_RAND,
+ GFC_ISYM_RANDOM_INIT,
GFC_ISYM_RANDOM_NUMBER,
GFC_ISYM_RANDOM_SEED,
GFC_ISYM_RANGE,
Index: gcc/fortran/intrinsic.c
===================================================================
--- gcc/fortran/intrinsic.c (revision 256953)
+++ gcc/fortran/intrinsic.c (working copy)
@@ -3555,6 +3555,12 @@ add_subroutines (void)
make_alias ("kmvbits", GFC_STD_GNU);
}
+ add_sym_2s ("random_init", GFC_ISYM_RANDOM_INIT, CLASS_IMPURE,
+ BT_UNKNOWN, 0, GFC_STD_F2018,
+ gfc_check_random_init, NULL, gfc_resolve_random_init,
+ "repeatable", BT_LOGICAL, dl, REQUIRED, INTENT_IN,
+ "image_distinct", BT_LOGICAL, dl, REQUIRED, INTENT_IN);
+
add_sym_1s ("random_number", GFC_ISYM_RANDOM_NUMBER, CLASS_IMPURE,
BT_UNKNOWN, 0, GFC_STD_F95,
gfc_check_random_number, NULL, gfc_resolve_random_number,
Index: gcc/fortran/intrinsic.h
===================================================================
--- gcc/fortran/intrinsic.h (revision 256953)
+++ gcc/fortran/intrinsic.h (working copy)
@@ -203,6 +203,7 @@ bool gfc_check_getlog (gfc_expr *);
bool gfc_check_move_alloc (gfc_expr *, gfc_expr *);
bool gfc_check_mvbits (gfc_expr *, gfc_expr *, gfc_expr *, gfc_expr *,
gfc_expr *);
+bool gfc_check_random_init (gfc_expr *, gfc_expr *);
bool gfc_check_random_number (gfc_expr *);
bool gfc_check_random_seed (gfc_expr *, gfc_expr *, gfc_expr *);
bool gfc_check_dtime_etime_sub (gfc_expr *, gfc_expr *);
@@ -648,6 +649,7 @@ void gfc_resolve_lstat_sub (gfc_code *);
void gfc_resolve_ltime (gfc_code *);
void gfc_resolve_mvbits (gfc_code *);
void gfc_resolve_perror (gfc_code *);
+void gfc_resolve_random_init (gfc_code *);
void gfc_resolve_random_number (gfc_code *);
void gfc_resolve_random_seed (gfc_code *);
void gfc_resolve_rename_sub (gfc_code *);
Index: gcc/fortran/intrinsic.texi
===================================================================
--- gcc/fortran/intrinsic.texi (revision 256953)
+++ gcc/fortran/intrinsic.texi (working copy)
@@ -262,6 +262,7 @@ Some basic guidelines for editing this document:
* @code{RADIX}: RADIX, Base of a data model
* @code{RAN}: RAN, Real pseudo-random number
* @code{RAND}: RAND, Real pseudo-random number
+* @code{RANDOM_INIT}: RANDOM_INIT, Initialize pseudo-random number generator
* @code{RANDOM_NUMBER}: RANDOM_NUMBER, Pseudo-random number
* @code{RANDOM_SEED}: RANDOM_SEED, Initialize a pseudo-random number sequence
* @code{RANGE}: RANGE, Decimal exponent range
@@ -11589,7 +11590,61 @@ end program test_rand
@end table
+@node RANDOM_INIT
+@section @code{RANDOM_INIT} --- Initialize a pseudo-random number generator
+@fnindex RANDOM_INIT
+@cindex random number generation, initialization
+@table @asis
+@item @emph{Description}:
+Initializes the state of the pseudorandom number generator used by
+@code{RANDOM_NUMBER}.
+
+@item @emph{Standard}:
+Fortran 2018
+
+@item @emph{Class}:
+Subroutine
+
+@item @emph{Syntax}:
+@code{CALL RANDOM_INIT(REPEATABLE, IMAGE_DISTINCT)}
+
+@item @emph{Arguments}:
+@multitable @columnfractions .20 .75
+@item @var{REPEATABLE} @tab Shall be a scalar with a @code{LOGICAL} type,
+and it is @code{INTENT(IN)}. If it is @code{.true.}, the seed is set to
+a processor-dependent value that is the same each time @code{RANDOM_INIT}
+is called from the same image. The term ``same image'' means a single
+instance of program execution. The sequence of random numbers is different
+for repeated execution of the program. If it is @code{.false.}, the seed
+is set to a processor-dependent value.
+@item @var{IMAGE_DISTINCT} @tab Shall be a scalar with a
+@code{LOGICAL} type, and it is @code{INTENT(IN)}. If it is @code{.true.},
+the seed is set to a processor-dependent value that is distinct from th
+seed set by a call to @code{RANDOM_INIT} in another image. If it is
+@code{.false.}, the seed is set value that does depend which image called
+@code{RANDOM_INIT}.
+@end multitable
+
+@item @emph{Example}:
+@smallexample
+program test_random_seed
+ implicit none
+ real x(3), y(3)
+ call random_init(.true., .true.)
+ call random_number(x)
+ call random_init(.true., .true.)
+ call random_number(y)
+ ! x and y are the same sequence
+ if (any(x /= y)) call abort
+end program test_random_seed
+@end smallexample
+
+@item @emph{See also}:
+@ref{RANDOM_NUMBER}, @ref{RANDOM_SEED}
+@end table
+
+
@node RANDOM_NUMBER
@section @code{RANDOM_NUMBER} --- Pseudo-random number
@fnindex RANDOM_NUMBER
@@ -11634,7 +11689,7 @@ end program
@end smallexample
@item @emph{See also}:
-@ref{RANDOM_SEED}
+@ref{RANDOM_SEED}, @ref{RANDOM_INIT}
@end table
@@ -11704,7 +11759,7 @@ end program test_random_seed
@end smallexample
@item @emph{See also}:
-@ref{RANDOM_NUMBER}
+@ref{RANDOM_NUMBER}, @ref{RANDOM_INIT}
@end table
Index: gcc/fortran/iresolve.c
===================================================================
--- gcc/fortran/iresolve.c (revision 256953)
+++ gcc/fortran/iresolve.c (working copy)
@@ -3388,6 +3388,17 @@ gfc_resolve_mvbits (gfc_code *c)
}
+/* Set up the call to RANDOM_INIT. */
+
+void
+gfc_resolve_random_init (gfc_code *c)
+{
+ const char *name;
+ name = gfc_get_string (PREFIX ("random_init"));
+ c->resolved_sym = gfc_get_intrinsic_sub_symbol (name);
+}
+
+
void
gfc_resolve_random_number (gfc_code *c)
{
Index: gcc/fortran/trans-decl.c
===================================================================
--- gcc/fortran/trans-decl.c (revision 256953)
+++ gcc/fortran/trans-decl.c (working copy)
@@ -221,6 +221,8 @@ tree gfor_fndecl_dgemm;
tree gfor_fndecl_cgemm;
tree gfor_fndecl_zgemm;
+/* RANDOM_INIT function. */
+tree gfor_fndecl_random_init;
static void
gfc_add_decl_to_parent_function (tree decl)
@@ -3314,6 +3316,11 @@ gfc_build_intrinsic_function_decls (void)
get_identifier (PREFIX("ctime")), ".W",
void_type_node, 3, pchar_type_node, gfc_charlen_type_node,
gfc_int8_type_node);
+
+ gfor_fndecl_random_init = gfc_build_library_function_decl (
+ get_identifier (PREFIX("random_init")),
+ void_type_node, 3, gfc_logical4_type_node, gfc_logical4_type_node,
+ gfc_int4_type_node);
gfor_fndecl_sc_kind = gfc_build_library_function_decl_with_spec (
get_identifier (PREFIX("selected_char_kind")), "..R",
Index: gcc/fortran/trans-intrinsic.c
===================================================================
--- gcc/fortran/trans-intrinsic.c (revision 256953)
+++ gcc/fortran/trans-intrinsic.c (working copy)
@@ -3484,6 +3484,52 @@ conv_intrinsic_free (gfc_code *code)
}
+/* Call the RANDOM_INIT library subroutine with a hidden argument for
+ handling seeding on coarray images. */
+
+static tree
+conv_intrinsic_random_init (gfc_code *code)
+{
+ stmtblock_t block;
+ gfc_se se;
+ tree arg1, arg2, arg3, tmp;
+ tree logical4_type_node = gfc_get_logical_type (4);
+
+ /* Make the function call. */
+ gfc_init_block (&block);
+ gfc_init_se (&se, NULL);
+
+ /* Convert REPEATABLE to a LOGICAL(4) entity. */
+ gfc_conv_expr (&se, code->ext.actual->expr);
+ gfc_add_block_to_block (&block, &se.pre);
+ arg1 = fold_convert (logical4_type_node, gfc_evaluate_now (se.expr, &block));
+ gfc_add_block_to_block (&block, &se.post);
+
+ /* Convert IMAGE_DISTINCT to a LOGICAL(4) entity. */
+ gfc_conv_expr (&se, code->ext.actual->next->expr);
+ gfc_add_block_to_block (&block, &se.pre);
+ arg2 = fold_convert (logical4_type_node, gfc_evaluate_now (se.expr, &block));
+ gfc_add_block_to_block (&block, &se.post);
+
+ /* Create the hidden argument. For non-coarray codes and -fcoarray=single,
+ simply set this to 0. For -fcoarray=lib, generate a call to
+ THIS_IMAGE() without arguments. */
+ arg3 = build_int_cst (gfc_get_int_type (4), 0);
+ if (flag_coarray == GFC_FCOARRAY_LIB)
+ {
+ arg3 = build_call_expr_loc (input_location, gfor_fndecl_caf_this_image,
+ 1, arg3);
+ se.expr = fold_convert (gfc_get_int_type (4), arg3);
+ }
+
+ tmp = build_call_expr_loc (input_location, gfor_fndecl_random_init, 3,
+ arg1, arg2, arg3);
+ gfc_add_expr_to_block (&block, tmp);
+
+ return gfc_finish_block (&block);
+}
+
+
/* Call the SYSTEM_CLOCK library functions, handling the type and kind
conversions. */
@@ -10725,6 +10771,10 @@ gfc_conv_intrinsic_subroutine (gfc_code *code)
case GFC_ISYM_FREE:
res = conv_intrinsic_free (code);
+ break;
+
+ case GFC_ISYM_RANDOM_INIT:
+ res = conv_intrinsic_random_init (code);
break;
case GFC_ISYM_SYSTEM_CLOCK:
Index: gcc/fortran/trans.h
===================================================================
--- gcc/fortran/trans.h (revision 256953)
+++ gcc/fortran/trans.h (working copy)
@@ -907,6 +907,8 @@ extern GTY(()) tree gfor_fndecl_sr_kind;
extern GTY(()) tree gfor_fndecl_ieee_procedure_entry;
extern GTY(()) tree gfor_fndecl_ieee_procedure_exit;
+/* RANDOM_INIT. */
+extern GTY(()) tree gfor_fndecl_random_init;
/* True if node is an integer constant. */
#define INTEGER_CST_P(node) (TREE_CODE(node) == INTEGER_CST)
Index: gcc/testsuite/gfortran.dg/random_init_1.f90
===================================================================
--- gcc/testsuite/gfortran.dg/random_init_1.f90 (nonexistent)
+++ gcc/testsuite/gfortran.dg/random_init_1.f90 (working copy)
@@ -0,0 +1,11 @@
+! { dg-do compile }
+program foo
+ logical a(2)
+ real x
+ call random_init(1., .false.) ! { dg-error "must be LOGICAL" }
+ call random_init(.true., 1) ! { dg-error "must be LOGICAL" }
+ call random_number(x)
+ a = .true.
+ call random_init(a, .false.) ! { dg-error "must be a scalar" }
+ call random_init(.false., a) ! { dg-error "must be a scalar" }
+end program foo
Index: gcc/testsuite/gfortran.dg/random_init_2.f90
===================================================================
--- gcc/testsuite/gfortran.dg/random_init_2.f90 (nonexistent)
+++ gcc/testsuite/gfortran.dg/random_init_2.f90 (working copy)
@@ -0,0 +1,30 @@
+! { dg-do run }
+program foo
+
+ real x(2), y(2)
+
+ call random_init(.false., .false.)
+ call random_number(x)
+! print *, x
+ x = int(1e6*x)
+
+ call random_init(.false., .false.)
+ call random_number(y)
+! print *, y
+ y = int(1e6*y)
+
+ if (any(x == y)) call abort
+
+ call random_init(.true., .false.)
+ call random_number(x)
+! print *, x
+ x = int(1e6*x)
+
+ call random_init(.true., .false.)
+ call random_number(y)
+! print *, y
+ y = int(1e6*y)
+
+ if (any(x /= y)) call abort
+
+end program foo
Index: gcc/testsuite/gfortran.dg/random_init_3.f90
===================================================================
--- gcc/testsuite/gfortran.dg/random_init_3.f90 (nonexistent)
+++ gcc/testsuite/gfortran.dg/random_init_3.f90 (working copy)
@@ -0,0 +1,74 @@
+! { dg-do run }
+! { dg-options "-fcoarray=single" }
+program rantest
+
+ implicit none
+
+ logical, parameter :: debug = .false.
+ character(len=20) name
+ integer fd, i, n
+ integer, allocatable :: n1(:), n2(:), n3(:)
+ real x(4), y(4), z(4)
+
+ if (debug) then
+ write(name,'(A,I0)') 'dat', this_image()
+ open(newunit=fd, file=name)
+ end if
+
+ call random_seed(size=n)
+ allocate(n1(n), n2(n), n3(n))
+ !
+ ! Setup repeatable sequences (if co-arrays the seeds should be distinct
+ ! are different). Get the seeds.
+ !
+ call random_init(.true., .true.)
+ call random_seed(get=n1)
+ call random_number(x) ! This changes internal state.
+ if (debug) then
+ write(fd,'(A,4F12.6)') 'x = ', x
+ end if
+
+ call random_seed(get=n2) ! Grab current state.
+ !
+ ! Use the gotten seed to reseed PRNG and grab sequence.
+ ! It should be the same sequence.
+ !
+ call random_seed(put=n1)
+ call random_number(y)
+ if (debug) then
+ write(fd,'(A,4F12.6)') 'y = ', y
+ end if
+ !
+ ! Setup repeatable sequences (if co-arrays the seeds should be distinct
+ ! are different). Get the seeds. It should be the same sequence.
+ !
+ call random_init(.true., .true.)
+ call random_seed(get=n3)
+ call random_number(z)
+ if (debug) then
+ write(fd,'(A,4F12.6)') 'z = ', z
+ end if
+
+ x = int(1e6*x) ! Convert to integer with at most 6 digits.
+ y = int(1e6*y) ! Convert to integer with at most 6 digits.
+ z = int(1e6*z) ! Convert to integer with at most 6 digits.
+
+ if (any(x /= y)) call abort
+ if (any(x /= z)) call abort
+
+ if (debug) then
+ write(fd,*)
+ do i = 1, n
+ if (n1(i) - n2(i) /= 0) then
+ write(fd,*) 'n1 /= n2', i, n1(i), n2(i)
+ end if
+ end do
+ write(fd,*)
+ do i = 1, n
+ if (n1(i) - n3(i) /= 0) then
+ write(fd,*) 'n1 /= n3', i, n1(i), n3(i)
+ end if
+ end do
+ end if
+
+end program rantest
Index: gcc/testsuite/gfortran.dg/random_init_4.f90
===================================================================
--- gcc/testsuite/gfortran.dg/random_init_4.f90 (nonexistent)
+++ gcc/testsuite/gfortran.dg/random_init_4.f90 (working copy)
@@ -0,0 +1,43 @@
+! { dg-do run }
+! { dg-options "-fcoarray=single" }
+program rantest
+
+ implicit none
+
+ logical, parameter :: debug = .false.
+ character(len=20) name
+ integer fd, i, n
+ integer, allocatable :: n1(:), n2(:), n3(:)
+ real x(4), y(4), z(4)
+
+ if (debug) then
+ write(name,'(A,I0)') 'dat', this_image()
+ open(newunit=fd, file=name)
+ end if
+
+ call random_seed(size=n)
+ allocate(n1(n), n2(n), n3(n))
+
+ call random_init(.true., .false.)
+ call random_seed(get=n1)
+ call random_number(x)
+
+ call random_init(.true., .false.)
+ call random_seed(get=n2)
+ call random_number(y)
+
+ call random_init(.true., .false.)
+ call random_seed(get=n3)
+ call random_number(z)
+
+ if (debug) then
+ write(fd,'(A,4F12.6)') 'x = ', x
+ write(fd,'(A,4F12.6)') 'y = ', y
+ write(fd,'(A,4F12.6)') 'z = ', z
+ write(fd,*)
+ do i = 1, 5
+ write(fd,'(I2,4I13)') i, n1(i), n2(i), n3(i)
+ end do
+ end if
+
+end program rantest
Index: gcc/testsuite/gfortran.dg/random_init_5.f90
===================================================================
--- gcc/testsuite/gfortran.dg/random_init_5.f90 (nonexistent)
+++ gcc/testsuite/gfortran.dg/random_init_5.f90 (working copy)
@@ -0,0 +1,43 @@
+! { dg-do run }
+! { dg-options "-fcoarray=single" }
+program rantest
+
+ implicit none
+
+ logical, parameter :: debug = .false.
+ character(len=20) name
+ integer fd, i, n
+ integer, allocatable :: n1(:), n2(:), n3(:)
+ real x(4), y(4), z(4)
+
+ if (debug) then
+ write(name,'(A,I0)') 'dat', this_image()
+ open(newunit=fd, file=name)
+ end if
+
+ call random_seed(size=n)
+ allocate(n1(n), n2(n), n3(n))
+
+ call random_init(.false., .false.)
+ call random_seed(get=n1)
+ call random_number(x)
+
+ call random_init(.false., .false.)
+ call random_seed(get=n2)
+ call random_number(y)
+
+ call random_init(.false., .false.)
+ call random_seed(get=n3)
+ call random_number(z)
+
+ if (debug) then
+ write(fd,'(A,4F12.6)') 'x = ', x
+ write(fd,'(A,4F12.6)') 'y = ', y
+ write(fd,'(A,4F12.6)') 'z = ', z
+ write(fd,*)
+ do i = 1, 5
+ write(fd,'(I2,4I13)') i, n1(i), n2(i), n3(i)
+ end do
+ end if
+
+end program rantest
Index: gcc/testsuite/gfortran.dg/random_init_6.f90
===================================================================
--- gcc/testsuite/gfortran.dg/random_init_6.f90 (nonexistent)
+++ gcc/testsuite/gfortran.dg/random_init_6.f90 (working copy)
@@ -0,0 +1,43 @@
+! { dg-do run }
+! { dg-options "-fcoarray=single" }
+program rantest
+
+ implicit none
+
+ logical, parameter :: debug = .false.
+ character(len=20) name
+ integer fd, i, n
+ integer, allocatable :: n1(:), n2(:), n3(:)
+ real x(4), y(4), z(4)
+
+ if (debug) then
+ write(name,'(A,I0)') 'dat', this_image()
+ open(newunit=fd, file=name)
+ end if
+
+ call random_seed(size=n)
+ allocate(n1(n), n2(n), n3(n))
+
+ call random_init(.false., .true.)
+ call random_seed(get=n1)
+ call random_number(x)
+
+ call random_init(.false., .true.)
+ call random_seed(get=n2)
+ call random_number(y)
+
+ call random_init(.false., .true.)
+ call random_seed(get=n3)
+ call random_number(z)
+
+ if (debug) then
+ write(fd,'(A,4F12.6)') 'x = ', x
+ write(fd,'(A,4F12.6)') 'y = ', y
+ write(fd,'(A,4F12.6)') 'z = ', z
+ write(fd,*)
+ do i = 1, 5
+ write(fd,'(I2,4I13)') i, n1(i), n2(i), n3(i)
+ end do
+ end if
+
+end program rantest
Index: libgfortran/Makefile.am
===================================================================
--- libgfortran/Makefile.am (revision 256953)
+++ libgfortran/Makefile.am (working copy)
@@ -915,7 +915,8 @@ $(gfor_built_specific_src) \
$(gfor_built_specific2_src) \
$(gfor_misc_specifics) \
intrinsics/dprod_r8.f90 \
-intrinsics/f2c_specifics.F90
+intrinsics/f2c_specifics.F90 \
+intrinsics/random_init.f90
# Turn on vectorization and loop unrolling for matmul.
$(patsubst %.c,%.lo,$(notdir $(i_matmul_c))): AM_CFLAGS += -ffast-math -ftree-vectorize -funroll-loops --param max-unroll-times=4
Index: libgfortran/Makefile.in
===================================================================
--- libgfortran/Makefile.in (revision 256953)
+++ libgfortran/Makefile.in (working copy)
@@ -408,7 +408,7 @@ am__objects_56 = _sign_i4.lo _sign_i8.lo _sign_i16.lo
_mod_r10.lo _mod_r16.lo
am__objects_57 = misc_specifics.lo
am__objects_58 = $(am__objects_55) $(am__objects_56) $(am__objects_57) \
- dprod_r8.lo f2c_specifics.lo
+ dprod_r8.lo f2c_specifics.lo random_init.lo
am__objects_59 = $(am__objects_3) $(am__objects_47) $(am__objects_49) \
$(am__objects_52) $(am__objects_53) $(am__objects_54) \
$(am__objects_58)
@@ -1374,7 +1374,8 @@ $(gfor_built_specific_src) \
$(gfor_built_specific2_src) \
$(gfor_misc_specifics) \
intrinsics/dprod_r8.f90 \
-intrinsics/f2c_specifics.F90
+intrinsics/f2c_specifics.F90 \
+intrinsics/random_init.f90
BUILT_SOURCES = $(gfor_built_src) $(gfor_built_specific_src) \
$(gfor_built_specific2_src) $(gfor_misc_specifics) \
@@ -6229,6 +6230,9 @@ selected_real_kind.lo: intrinsics/selected_real_kind.f
dprod_r8.lo: intrinsics/dprod_r8.f90
$(LIBTOOL) --tag=FC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(FC) $(AM_FCFLAGS) $(FCFLAGS) -c -o dprod_r8.lo `test -f 'intrinsics/dprod_r8.f90' || echo '$(srcdir)/'`intrinsics/dprod_r8.f90
+
+random_init.lo: intrinsics/random_init.f90
+ $(LIBTOOL) --tag=FC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(FC) $(AM_FCFLAGS) $(FCFLAGS) -c -o random_init.lo `test -f 'intrinsics/random_init.f90' || echo '$(srcdir)/'`intrinsics/random_init.f90
mostlyclean-libtool:
-rm -f *.lo
Index: libgfortran/gfortran.map
===================================================================
--- libgfortran/gfortran.map (revision 256953)
+++ libgfortran/gfortran.map (working copy)
@@ -801,6 +801,7 @@ GFORTRAN_8 {
_gfortran_product_r4;
_gfortran_product_r8;
_gfortran_rand;
+ _gfortran_random_init;
_gfortran_random_r10;
_gfortran_random_r16;
_gfortran_random_r4;
Index: libgfortran/intrinsics/random_init.f90
===================================================================
--- libgfortran/intrinsics/random_init.f90 (nonexistent)
+++ libgfortran/intrinsics/random_init.f90 (working copy)
@@ -0,0 +1,94 @@
+! Copyright (C) 2018 Free Software Foundation, Inc.
+! Contributed by Steven G. Kargl <ka...@gcc.gnu.org>
+!
+! This file is part of the GNU Fortran runtime library (libgfortran).
+!
+! Libgfortran is free software; you can redistribute it and/or
+! modify it under the terms of the GNU General Public
+! License as published by the Free Software Foundation; either
+! version 3 of the License, or (at your option) any later version.
+!
+! Libgfortran is distributed in the hope that it will be useful,
+! but WITHOUT ANY WARRANTY; without even the implied warranty of
+! MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+! GNU General Public License for more details.
+!
+! Under Section 7 of GPL version 3, you are granted additional
+! permissions described in the GCC Runtime Library Exception, version
+! 3.1, as published by the Free Software Foundation.
+!
+! You should have received a copy of the GNU General Public License and
+! a copy of the GCC Runtime Library Exception along with this program;
+! see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
+! <http://www.gnu.org/licenses/>.
+!
+!
+! WARNING: This file should never be compiled with an option that changes
+! default logical kind from 4 to some other value or changes default integer
+! kind from from 4 to some other value.
+!
+!
+! There are four combinations of repeatable and image_distinct. If a program
+! is compiled without the -fcoarray= option or with -fcoarray=single, then
+! execution of the compiled executable does not used image_distinct as it is
+! irrelevant (although required). The behavior is as follows:
+!
+! call random_init(.true., .true.)
+!
+! The sequence of random numbers is repeatable with an instance of program
+! execution. That is, calls to call random_init(.true., .true.) during the
+! execution will reset the sequence of RN to the same sequence. If the
+! program is compiled with -fcoarray=lib and multiple images are instantiated,
+! then each image accesses a repeatable distinct sequence of random numbers.
+! There are no guarantees that multiple execution of the program will access
+! the same sequence.
+!
+! call random_init(.false., .false.)
+! call random_init(.false., .true.)
+!
+! The sequence of random numbers is determined from process-dependent seeds.
+! On each execution of the executable, different seeds will be used. For
+! -fcoarray=lib and multiple instantiated images, each image will use
+! process-dependent seeds. In other words, the two calls have identical
+! behavior.
+!
+! call random_init(.true., .false.)
+!
+! For a program compiled without the -fcoarray= option or with
+! -fcoarray=single, a single image is instantiated when the executable is
+! run. If the executable causes multiple images to be instantiated, then
+! image_distinct=.false. in one image cannot affect the sequence of random
+! numbers in another image. As gfortran gives each image its own independent
+! PRNG, this conditions is automatically satisfied.
+!
+impure subroutine _gfortran_random_init(repeatable, image_distinct, hidden)
+
+ implicit none
+
+ logical, value, intent(in) :: repeatable
+ logical, value, intent(in) :: image_distinct
+ integer, value, intent(in) :: hidden
+
+ logical, save :: once = .true.
+ integer :: nseed
+ integer, save, allocatable :: seed(:)
+
+ if (once) then
+ once = .false.
+ call random_seed(size=nseed)
+ allocate(seed(nseed))
+ call random_seed(get=seed)
+ !
+ ! To guarantee that seed is distinct on multiple images, add the hidden
+ ! argument (which is the image index).
+ !
+ if (image_distinct) seed = seed + hidden
+ end if
+
+ if (repeatable) then
+ call random_seed(put=seed);
+ else
+ call random_seed();
+ end if
+
+end subroutine _gfortran_random_init
