adam_prism_fnl_object

ADAM, PRISM (Plasma Research usIng Simulation Methods) equations system class definition, GPU (FNL) backend.

Source: src/app/prism/fnl/adam_prism_fnl_object.F90

Dependencies

Contents

• prism_fnl_object
• compute_curl_interface_dev
• compute_derivative1_interface_dev
• compute_derivative2_interface_dev
• compute_derivative4_interface_dev
• compute_divergence_interface_dev
• compute_gradient_interface_dev
• compute_laplacian_interface_dev
• compute_residuals_interface_dev
• integrate_interface_dev
• allocate_gpu
• copy_cpu_gpu
• copy_gpu_cpu
• initialize_prism
• load_restart_files
• save_residuals
• save_simulation_data
• apply_fwl_correction
• compute_coils_current
• set_boundary_conditions
• set_initial_conditions
• update_ghost
• update_rk_ghost
• compute_curl_fd_dev
• compute_curl_fv_dev
• compute_derivative1_fd_dev
• compute_derivative1_fv_dev
• compute_derivative2_fd_dev
• compute_derivative2_fv_dev
• compute_derivative4_fd_dev
• compute_divergence_fd_dev
• compute_divergence_fv_dev
• compute_gradient_fd_dev
• compute_gradient_fv_dev
• compute_laplacian_fd_dev
• compute_laplacian_fv_dev
• compute_residuals_fd_centered_dev
• integrate_blanesmoan_dev
• integrate_cfm_dev
• integrate_leapfrog_dev
• integrate_leapfrog_pic
• integrate_rk_ls_dev
• integrate_rk_ssp_dev
• integrate_rk_yoshida_dev
• is_done_forest
• finalize_forest
• finalize_mpi_forest
• simulate
• initialize_forest
• compute_local_dt_forest
• advance_one_step_forest
• open_step_forest
• begin_stage_forest
• end_stage_forest
• close_step_forest
• fill_seam_from_peer_forest
• after_topology_build_forest
• apply_reflux_to_stage_forest
• post_step_forest
• compute_dt
• compute_energy
• compute_energy_error
• compute_max_divergence
• impose_ct_correction
• impose_div_free
• stages_per_step_forest

Derived Types

prism_fnl_object

PRISM equations system class definition, GPU (FNL) backend.

Inheritance

Extends: prism_common_object

Components

Name	Type	Attributes	Description
io	type(io_object)		IO handler.
amr	type(amr_object)		AMR marker handler.
slices	type(slices_object)		Slices handler.
blanesmoan	type(blanesmoan_object)		Blanes-Moan integrator.
cfm	type(cfm_object)		Commutator-Free Magnus integrator.
leapfrog	type(leapfrog_object)		Leapfrog integrator.
flail	type(flail_object)		Linear algebra methods handler.
weno	type(weno_object)		WENO reconstructor.
ib	type(ib_object)		Immersed boundary.
rk	type(rk_object)		Runge-Kutta integrator.
adam	type(adam_object)		ADAM, grid + tree + field + maps orchestrator.
fdv_scheme	character(len=:)	allocatable	FDV scheme, fd/fv.
fdv_order	integer(kind=I4P)		Order of finite difference/volume schemes, general order.
fdv_half_stencil	integer(kind=I4P)		Half stencil length of finite difference/volume schemes.
fdv_half_stencils	integer(kind=I4P)		Half stencil length of fdv schemes for each derivative up to 6.
ngc	integer(kind=I4P)	pointer	Number of ghost cells.
ni	integer(kind=I4P)	pointer	Number of cells in i direction.
nj	integer(kind=I4P)	pointer	Number of cells in j direction.
nk	integer(kind=I4P)	pointer	Number of cells in k direction.
nb	integer(kind=I4P)	pointer	Total blocks number for MPI.
blocks_number	integer(kind=I4P)	pointer	Actual blocks number.
nv	integer(kind=I4P)	pointer	Number of variables in q vector.
realm_index	integer(kind=I4P)		Inter-realm seam coupling — currently-published stage buffer key.
stage_active	integer(kind=I4P)		Procedure pointer TBPs for FDV operators (set at initialization by backend).
compute_block_total_variation	procedure(compute_block_total_variation_interface)	pass(self), pointer	Compute TV.
compute_curl	procedure(compute_curl_interface)	pass(self), pointer	Compute curl.
compute_derivative1	procedure(compute_derivative1_interface)	pass(self), pointer	Compute deriv1.
compute_derivative2	procedure(compute_derivative2_interface)	pass(self), pointer	Compute deriv2.
compute_derivative4	procedure(compute_derivative4_interface)	pass(self), pointer	Compute deriv4.
compute_divergence	procedure(compute_divergence_interface)	pass(self), pointer	Compute dive.
compute_gradient	procedure(compute_gradient_interface)	pass(self), pointer	Compute grad.
compute_laplacian	procedure(compute_laplacian_interface)	pass(self), pointer	Compute laplac.
nv_c	integer(kind=I4P)	pointer	Number of conservative variables in q vector.
nv_s	integer(kind=I4P)	pointer	Number of source variables in q vector.
nv_cl	integer(kind=I4P)	pointer	Number of divergence cleaning variables in q vector.
q	real(kind=R8P)	allocatable	Conservative cell centered variables.
dq	real(kind=R8P)	allocatable	Residuals right hand side.
q_pic	real(kind=R8P)	allocatable	PIC variables.
pic_fields	real(kind=R8P)	allocatable	Fields value at particle locations.
curl	real(kind=R8P)	allocatable	Curl fields.
divergence	real(kind=R8P)	allocatable	Divergence fields.
q_name	type(string)	allocatable	Fields names [1:nv].
dq_name	type(string)	allocatable	Residuals names [1:nv].
q_pic_name	type(string)	allocatable	PIC Fields names.
curl_name	type(string)	allocatable	Curl fields names.
div_name	type(string)	allocatable	Divergence fields names.
energy_D	real(kind=R8P)	allocatable	Energy of field D, time history.
energy_B	real(kind=R8P)	allocatable	Energy of field B, time history.
coil_power	real(kind=R8P)	allocatable	Power of coils, time history.
Poynting_flux	real(kind=R8P)	allocatable	Total Poynting flux from boundary, time history.
rms_energy_error_D	real(kind=R8P)		RMS energy error of D field.
rms_energy_error_B	real(kind=R8P)		RMS energy error of B field.
max_divergence_D	real(kind=R8P)		Maximum of divergence of D field.
max_divergence_B	real(kind=R8P)		Maximum of divergence of B field.
max_divergence_J	real(kind=R8P)		Maximum of divergence of J field.
bc	type(prism_bc_object)		Boundary conditions.
coil	type(prism_coil_object)		Coil source term.
external_fields	type(prism_external_fields_object)		External fields.
fWLayer	type(prism_fWLayer_object)		Far-field weighted layer.
ic	type(prism_ic_object)		Initial conditions.
leapfrog_pic	type(prism_leapfrog_pic_object)		Leapfrog PIC integrator.
numerics	type(prism_numerics_object)		Numerics configuration.
particle_injection	type(prism_particle_injection_object)		Particle injection.
physics	type(prism_physics_object)		Physics configuration.
pic	type(prism_pic_object)		PIC state.
rk_bc	type(prism_rk_bc_object)		Runge-Kutta BC handler.
rk_pic	type(prism_rk_pic_object)		Runge-Kutta PIC handler.
time	type(prism_time_object)		Time integration state.
field_fnl	type(field_fnl_object)		GPU field handler.
ib_fnl	type(ib_fnl_object)		GPU immersed boundary.
rk_fnl	type(rk_fnl_object)		GPU Runge-Kutta integrator.
weno_fnl	type(weno_fnl_object)		GPU WENO reconstructor.
coil_fnl	type(prism_fnl_coil_object)		GPU coil source.
fwlayer_fnl	type(prism_fnl_fwlayer_object)		GPU fWLayer.
q_gpu	real(kind=R8P)	pointer	Field cell centered variables.
dq_gpu	real(kind=R8P)	pointer	Residuals right hand side.
flxyz_c_gpu	real(kind=R8P)	pointer	Fluxes at cell center with +/- decomposition for all directions.
flx_f_gpu	real(kind=R8P)	pointer	Fluxes along x at cell face.
fly_f_gpu	real(kind=R8P)	pointer	Fluxes along y at cell face.
flz_f_gpu	real(kind=R8P)	pointer	Fluxes along z at cell face.
curl_gpu	real(kind=R8P)	pointer	Curl fields.
divergence_gpu	real(kind=R8P)	pointer	Divergence fields.
db5	integer(kind=I4P)		Device data bounds (rank 5): bb(1,:)=lower, bb(2,:)=upper.
hb5	integer(kind=I4P)		Host buffer data bounds (rank 5): bb(1,:)=lower, bb(2,:)=upper.
buf_5D_R8P	real(kind=R8P)	allocatable	Buffer (host memory, device shape), rank 5, R8P.
compute_curl_dev	procedure(compute_curl_interface_dev)	pass(self), pointer	Compute curl.
compute_derivative1_dev	procedure(compute_derivative1_interface_dev)	pass(self), pointer	Compute derivative1.
compute_derivative2_dev	procedure(compute_derivative2_interface_dev)	pass(self), pointer	Compute derivative2.
compute_derivative4_dev	procedure(compute_derivative4_interface_dev)	pass(self), pointer	Compute derivative4.
compute_divergence_dev	procedure(compute_divergence_interface_dev)	pass(self), pointer	Compute divergence.
compute_gradient_dev	procedure(compute_gradient_interface_dev)	pass(self), pointer	Compute gradient.
compute_laplacian_dev	procedure(compute_laplacian_interface_dev)	pass(self), pointer	Compute laplacian.
compute_residuals_dev	procedure(compute_residuals_interface_dev)	pass(self), pointer	Compute residuals.
integrate_dev	procedure(integrate_interface_dev)	pass(self), pointer	Integrate, time operator.

Type-Bound Procedures

Name	Attributes	Description
load_fdv_from_file	pass(self)	Load FDV config from file.
close_block_xh5f	nopass	Close XH5F file block.
close_file_xh5f	nopass	Close XH5F file.
open_block_xh5f	pass(self)	Open block file XH5F.
open_file_xh5f	pass(self)	Open file XH5F.
save_q_xh5f	pass(self)	Save in XH5F (XDMF/HDF5) format.
allocate_common	pass(self)	Allocate common data.
compute_auxiliary_fields	pass(self)	Compute auxiliary fields.
initialize	pass(self)	Initialize the equation common data.
save_energy_error	pass(self)	Save energy error history.
save_energy_history	pass(self)	Save energy history.
save_divergence_history	pass(self)	Save divergence history.
save_restart_files	pass(self)	Save restart files.
save_xh5f	pass(self)	Save simulation data in XH5F format.
initialize_coils	pass(self)	Initialize coils.
set_rectangular_coil_x	pass(self)	Subroutine to set a rectangular coil source with +-x normal
set_rectangular_coil_y	pass(self)	Subroutine to set a rectangular coil source with +-y normal
set_rectangular_coil_z	pass(self)	Subroutine to set a rectangular coil source with +-z normal
set_circular_coil_x	pass(self)	Subroutine to set a circular coil source with +-x normal
set_circular_coil_y	pass(self)	Subroutine to set a circular coil source with +-y normal
set_circular_coil_z	pass(self)	Subroutine to set a circular coil source with +-z normal
set_solenoid_x	pass(self)	Subroutine to set a solenoid source with +-x normal
set_solenoid_y	pass(self)	Subroutine to set a solenoid source with +-y normal
set_solenoid_z	pass(self)	Subroutine to set a solenoid source with +-z normal
set_helicon_coil	pass(self)	Subroutine to set a helicon coil source.
coupling_descriptor_forest	pass(self)	Report (scheme_time, rk_scheme, nv) for β admissibility.
allocate_gpu	pass(self)	Allocate GPU data.
copy_cpu_gpu	pass(self)	Copy data from CPU to GPU.
copy_gpu_cpu	pass(self)	Copy data from GPU to CPU.
initialize_prism	pass(self)	Initialize PRISM equation.
load_restart_files	pass(self)	Load restart files.
save_residuals	pass(self)	Save residuals history.
save_simulation_data	pass(self)	Save all simulation data.
apply_fwl_correction	pass(self)	Apply fWLayer correction (if present)
compute_coils_current	pass(self)	Compute current coils sources.
set_boundary_conditions	pass(self)	Set boundary conditions of equation.
set_initial_conditions	pass(self)	Set initial conditions of equation.
update_ghost	pass(self)	Update ghost cells and set boundary conditions.
update_rk_ghost	pass(self)	Update RK stage ghost cells.
compute_curl_fd_dev	pass(self)	Compute curl of vector field by finite difference.
compute_curl_fv_dev	pass(self)	Compute curl of vector field by finite volume.
compute_derivative1_fd_dev	pass(self)	Compute derivative1 of scalar fields, finite difference schemes.
compute_derivative1_fv_dev	pass(self)	Compute derivative1 of scalar fields, finite volume schemes.
compute_derivative2_fd_dev	pass(self)	Compute derivative2 of scalar fields, finite difference schemes.
compute_derivative2_fv_dev	pass(self)	Compute derivative2 of scalar fields, finite volume schemes.
compute_derivative4_fd_dev	pass(self)	Compute derivative4 of scalar fields, finite difference schemes.
compute_divergence_fd_dev	pass(self)	Compute divergence of vector field by finite difference.
compute_divergence_fv_dev	pass(self)	Compute divergence of vector field by finite volume.
compute_gradient_fd_dev	pass(self)	Compute gradient of scalar field, finite difference schemes.
compute_gradient_fv_dev	pass(self)	Compute gradient of scalar field, finite volume schemes.
compute_laplacian_fd_dev	pass(self)	Compute laplacian of scalar field, finite difference schemes.
compute_laplacian_fv_dev	pass(self)	Compute laplacian of scalar field, finite volume schemes.
compute_residuals_fd_centered_dev	pass(self)	Compute residuals, centered finite difference schemes.
integrate_blanesmoan_dev	pass(self)	Blanes and Moan scheme.
integrate_cfm_dev	pass(self)	Commutator-Free Magnus scheme.
integrate_leapfrog_dev	pass(self)	Leapfrog scheme.
integrate_rk_ls_dev	pass(self)	RK classical low storage schemes.
integrate_rk_ssp_dev	pass(self)	SSP RK schemes.
integrate_rk_yoshida_dev	pass(self)	Yoshida schemes.
initialize_forest	pass(self)	Invoked by forest%initialize per realm at startup.
compute_local_dt_forest	pass(self)	Invoked by forest%compute_global_dt during the min reduction.
advance_one_step_forest	pass(self)	Invoked by forest%evolve_one_step per realm per timestep.
stages_per_step_forest	pass(self)	Number of integrator stages this realm exposes per step.
open_step_forest	pass(self)	Per-step prologue (multi-realm path).
begin_stage_forest	pass(self)	Begin one integrator stage on this realm (multi-realm path).
end_stage_forest	pass(self)	End the stage: residuals + assignment (multi-realm path).
close_step_forest	pass(self)	Per-step epilogue (multi-realm path).
post_step_forest	pass(self)	Invoked by forest%post_step per realm per timestep.
is_done_forest	pass(self)	Invoked by forest%is_done during the termination reduction.
finalize_forest	pass(self)	Invoked by forest%finalize per realm at shutdown.
finalize_mpi_forest	pass(self)	Process-global MPI finalize (mpih_fnl).
fill_seam_from_peer_forest	pass(self)	OpenACC device-direct copy of peer's GPU interior into self's GPU ghosts.
after_topology_build_forest	pass(self)	Refresh device-resident seam maps from freshly-built host maps.
apply_reflux_to_stage_forest	pass(self)	Apply Berger-Colella reflux to self's RK stage buffer (FNL no-op).
compute_dt	pass(self)	Compute time step.
compute_energy	pass(self)	Compute energy.
compute_energy_error	pass(self)	Compute energy error.
compute_max_divergence	pass(self)	Compute divergence of D, B and J fields for diagnostics.
impose_ct_correction	pass(self)	Impose Constrained Transport correction on q(ivar:ivar+2).
impose_div_free	pass(self)	Impose divergence-free property.
simulate	pass(self)	Perform the simulation.

Interfaces

compute_curl_interface_dev

compute_derivative1_interface_dev

compute_derivative2_interface_dev

compute_derivative4_interface_dev

compute_divergence_interface_dev

compute_gradient_interface_dev

compute_laplacian_interface_dev

compute_residuals_interface_dev

integrate_interface_dev

Subroutines

allocate_gpu

Allocate GPU data.

subroutine allocate_gpu(self)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The equation.

Call graph

copy_cpu_gpu

Copy data from CPU to GPU.

subroutine copy_cpu_gpu(self, verbose)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The equation.
verbose	logical	in	optional	Trigger verbose output.

Call graph

copy_gpu_cpu

Copy data from GPU to CPU.

subroutine copy_gpu_cpu(self, compute_copy_q_aux, copy_phi, verbose)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The equation.
compute_copy_q_aux	logical	in	optional	Flag to compute auxiliary variables.
copy_phi	logical	in	optional	Copy also phi.
verbose	logical	in	optional	Trigger verbose output.

Call graph

initialize_prism

Initialize PRISM equation.

subroutine initialize_prism(self, filename, realms_number)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout	target	The equation.
filename	character(len=*)	in		Input file name.
realms_number	integer(kind=I4P)	in	optional	Forest realm count; divides the per-device budget

Call graph

load_restart_files

Save restart files.

subroutine load_restart_files(self, t, time)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The equation.
t	integer(kind=I4P)	out		Time iteration.
time	real(kind=R8P)	out		Time.

Call graph

save_residuals

Save residuals history.

subroutine save_residuals(self)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The equation.

Call graph

save_simulation_data

Save all simulation data.

subroutine save_simulation_data(self)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The equation.

Call graph

apply_fwl_correction

Apply correction if a fWL is present.

subroutine apply_fwl_correction(self, q_gpu)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The equation.
q_gpu	real(kind=R8P)	inout		Conservative variables.

Call graph

compute_coils_current

Compute current coils sources.

subroutine compute_coils_current(self, q_gpu, gamm)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	in		The equation.
q_gpu	real(kind=R8P)	inout		Conservative variables.
gamm	real(kind=R8P)	in	optional	RK coefficient.

Call graph

set_boundary_conditions

Set boundary conditions of equation.

subroutine set_boundary_conditions(self, q_gpu)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	in		The equation.
q_gpu	real(kind=R8P)	inout		Conservative variables.

Call graph

set_initial_conditions

Set initial conditions of field.

subroutine set_initial_conditions(self, is_restart)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The equation.
is_restart	logical	in		Branching sentinel for restart/non restart path.

Call graph

update_ghost

Update ghost cells (intra-realm only).

Inter-realm seam ghost cells are filled by the forest's Phase 2 seam exchange (between assemble and evaluate) via fill_seam_from_peer_forest, NOT here. The legacy realm(:) optional dummy and the exchange_inter_realm_halos_forest call have been retired by the agnostic-dummy seam redesign.

subroutine update_ghost(self, q_gpu, step, s)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The equation.
q_gpu	real(kind=R8P)	inout		Conservative variables.
step	integer(kind=I4P)	in	optional	Step to be performed in async comp.
s	integer(kind=I4P)	in	optional	Stage counter.

Call graph

update_rk_ghost

Update RK ghost cells.

subroutine update_rk_ghost(self, dt, phi_gpu)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		RK object.
dt	real(kind=R8P)	in		Current time step.
phi_gpu	real(kind=R8P)	in	optional	IB distance.

compute_curl_fd_dev

Compute curl of vector fields, div(q(ivar:ivar+2), using finite difference schemes.

subroutine compute_curl_fd_dev(self, ivar, q_gpu, curl_gpu)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	in		The equation.
ivar	integer(kind=I4P)	in		Start index of variable of q.
q_gpu	real(kind=R8P)	in		Field variables.
curl_gpu	real(kind=R8P)	inout		Curl.

Call graph

compute_curl_fv_dev

Compute curl of vector fields, div(q(ivar:ivar+2), using finite volume schemes.

subroutine compute_curl_fv_dev(self, ivar, q_gpu, curl_gpu)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	in		The equation.
ivar	integer(kind=I4P)	in		Start index of variable of q.
q_gpu	real(kind=R8P)	in		Field variables.
curl_gpu	real(kind=R8P)	inout		Curl.

compute_derivative1_fd_dev

Compute derivative1 of scalar fields, dq(ivar)/ds, using finite difference schemes.

subroutine compute_derivative1_fd_dev(self, dir, ivar, q_gpu, dq_ds_gpu)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	in		The equation.
dir	integer(kind=I4P)	in		Direction, 1=X, 2=Y, 3=Z.
ivar	integer(kind=I4P)	in		Start index of variable of q.
q_gpu	real(kind=R8P)	in		Field variables.
dq_ds_gpu	real(kind=R8P)	inout		Derivative1, dq/ds.

compute_derivative1_fv_dev

Compute derivative1 of scalar fields, dq(ivar)/ds, using finite volume schemes.

subroutine compute_derivative1_fv_dev(self, dir, ivar, q_gpu, dq_ds_gpu)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	in		The equation.
dir	integer(kind=I4P)	in		Direction, 1=X, 2=Y, 3=Z.
ivar	integer(kind=I4P)	in		Start index of variable of q.
q_gpu	real(kind=R8P)	in		Field variables.
dq_ds_gpu	real(kind=R8P)	inout		Derivative1, dq/ds.

compute_derivative2_fd_dev

Compute derivative2 of scalar fields, d2q(ivar)/ds2, using finite difference schemes.

subroutine compute_derivative2_fd_dev(self, dir, ivar, q_gpu, d2q_ds2_gpu)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	in		The equation.
dir	integer(kind=I4P)	in		Direction, 1=X, 2=Y, 3=Z.
ivar	integer(kind=I4P)	in		Start index of variable of q.
q_gpu	real(kind=R8P)	in		Field variables.
d2q_ds2_gpu	real(kind=R8P)	inout		Derivative2, d2q/ds2.

compute_derivative2_fv_dev

Compute derivative2 of scalar fields, d2q(ivar)/ds2, using finite volume schemes.

subroutine compute_derivative2_fv_dev(self, dir, ivar, q_gpu, d2q_ds2_gpu)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	in		The equation.
dir	integer(kind=I4P)	in		Direction, 1=X, 2=Y, 3=Z.
ivar	integer(kind=I4P)	in		Start index of variable of q.
q_gpu	real(kind=R8P)	in		Field variables.
d2q_ds2_gpu	real(kind=R8P)	inout		Derivative2, d2q/ds2.

compute_derivative4_fd_dev

Compute derivative4 of scalar fields, d4q(ivar)/ds4, using finite difference schemes.

subroutine compute_derivative4_fd_dev(self, dir, ivar, q_gpu, d4q_ds4_gpu)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	in		The equation.
dir	integer(kind=I4P)	in		Direction, 1=X, 2=Y, 3=Z.
ivar	integer(kind=I4P)	in		Start index of variable of q.
q_gpu	real(kind=R8P)	in		Field variables.
d4q_ds4_gpu	real(kind=R8P)	inout		Derivative4, d4q/ds4.

compute_divergence_fd_dev

Compute divergence of vector fields, div(q(ivar:ivar+2), using finite difference schemes. Directly computes divergence from transposed GPU layout (b,i,j,k,v).

subroutine compute_divergence_fd_dev(self, ivar, ovar, q_gpu, divergence_gpu, maxdiv)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	in		The equation.
ivar	integer(kind=I4P)	in		Start index of
ovar	integer(kind=I4P)	in		Output index in
q_gpu	real(kind=R8P)	in		Field variables.
divergence_gpu	real(kind=R8P)	inout		Divergence.
maxdiv	real(kind=R8P)	out	optional	Max divergence,

Call graph

compute_divergence_fv_dev

Compute divergence of vector fields, div(q(ivar:ivar+2), using finite volume schemes. Directly computes divergence from transposed GPU layout (b,i,j,k,v).

subroutine compute_divergence_fv_dev(self, ivar, ovar, q_gpu, divergence_gpu, maxdiv)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	in		The equation.
ivar	integer(kind=I4P)	in		Start index of
ovar	integer(kind=I4P)	in		Output index in
q_gpu	real(kind=R8P)	in		Field variables.
divergence_gpu	real(kind=R8P)	inout		Divergence.
maxdiv	real(kind=R8P)	out	optional	Max divergence,

compute_gradient_fd_dev

Compute gradient of scalar variable q(ivar), finite difference schemes.

subroutine compute_gradient_fd_dev(self, ivar, q_gpu, gradient_gpu)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	in		The equation.
ivar	integer(kind=I4P)	in		Index of scalar var of q.
q_gpu	real(kind=R8P)	in		Field variables.
gradient_gpu	real(kind=R8P)	inout		Gradient.

compute_gradient_fv_dev

Compute gradient of scalar variable q(ivar), finite volume schemes.

subroutine compute_gradient_fv_dev(self, ivar, q_gpu, gradient_gpu)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	in		The equation.
ivar	integer(kind=I4P)	in		Index of scalar var of q.
q_gpu	real(kind=R8P)	in		Field variables.
gradient_gpu	real(kind=R8P)	inout		Gradient.

compute_laplacian_fd_dev

Compute laplacian of scalar variable q(ivar), finite difference schemes.

subroutine compute_laplacian_fd_dev(self, ivar, q_gpu, laplacian_gpu)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	in		The equation.
ivar	integer(kind=I4P)	in		Index of scalar variable of q.
q_gpu	real(kind=R8P)	in		Field variables.
laplacian_gpu	real(kind=R8P)	inout		Gradient.

compute_laplacian_fv_dev

Compute laplacian of scalar variable q(ivar), finite volume schemes.

subroutine compute_laplacian_fv_dev(self, ivar, q_gpu, laplacian_gpu)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	in		The equation.
ivar	integer(kind=I4P)	in		Index of scalar variable of q.
q_gpu	real(kind=R8P)	in		Field variables.
laplacian_gpu	real(kind=R8P)	inout		Gradient.

compute_residuals_fd_centered_dev

Compute residuals of equation, space operator, centered finite difference schemes.

subroutine compute_residuals_fd_centered_dev(self, q_gpu, dq_gpu, s)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The equation.
q_gpu	real(kind=R8P)	inout		Conservative variables.
dq_gpu	real(kind=R8P)	inout		Residuals.
s	integer(kind=I4P)	in	optional	Stage counter.

Call graph

integrate_blanesmoan_dev

Integrate equation, time operator, Blanes and Moan scheme.

subroutine integrate_blanesmoan_dev(self)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The equation.

integrate_cfm_dev

Integrate equation, time operator, Commutator-Free Magnus integrator.

subroutine integrate_cfm_dev(self)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The equation.

integrate_leapfrog_dev

Integrate equation, time operator, leapfrog scheme.

subroutine integrate_leapfrog_dev(self)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The equation.

integrate_leapfrog_pic

Integrate equation, time operator, leapfrog scheme.

subroutine integrate_leapfrog_pic(self)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The equation.

integrate_rk_ls_dev

Integrate equation, time operator, RK classical low storage schemes. Low storage RK working on q_rk(:,:,:,:,:,1)/q as stages, update q in place.

subroutine integrate_rk_ls_dev(self)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The equation.

Call graph

integrate_rk_ssp_dev

Integrate equation, time operator, SSP RK schemes. SSP RK working on q_rk as stages.

subroutine integrate_rk_ssp_dev(self)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The equation.

Call graph

integrate_rk_yoshida_dev

Integrate equation, time operator, Yoshida RK scheme.

subroutine integrate_rk_yoshida_dev(self)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The equation.

is_done_forest

Decide whether this realm has reached its local termination criterion.

Invoked by forest%is_done. PRISM-FNL override: matches the legacy condition inline in simulate — terminate when either the simulated time has reached self%time%time_max (time-driven mode, it_max <= 0) or the iteration count has reached self%time%it_max (iteration-driven mode). Today the test reads time-state from the time module singleton, so self is unused; once the forest takes over time bookkeeping the body will consume self%time%* instead.

subroutine is_done_forest(self, done)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	in		The realm.
done	logical	out		True if this realm is done evolving.

Call graph

finalize_forest

Shut this realm down: final state dump, close residuals file, finalize MPI handler.

subroutine finalize_forest(self)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The realm.

Call graph

finalize_mpi_forest

Finalize the process-global FNL MPI handler (mpih_fnl).

Overrides realm_object%finalize_mpi_forest to target the FNL mpih_fnl singleton instead of the CPU mpih. Called ONCE by forest%finalize after every realm's finalize_forest (see the base for the rationale).

subroutine finalize_mpi_forest(self)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The realm (carries no MPI state).

Call graph

simulate

Perform the simulation: legacy single-realm entry point.

subroutine simulate(self, filename)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The equation.
filename	character(len=*)	in		Input file name.

Call graph

initialize_forest

Initialize this realm from scratch: PRISM init, IC injection (or restart load), initial ghost update, initial diagnostics dump, IO files open, plus PIC/leapfrog priming if those schemes are active.

Invoked by forest%initialize. The forest writes self%realm_index = is BEFORE calling this routine, so the body can already read the 1-based forest position from self%realm_index if needed.

subroutine initialize_forest(self, filename, realms_number, memory_avail, nv, verbose)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The realm.
filename	character(len=*)	in		Input parameters file name.
realms_number	integer(kind=I4P)	in	optional	Realm count; divides the per-device budget.
memory_avail	real(kind=R8P)	in	optional	Per-process memory budget override.
nv	integer(kind=I4P)	in	optional	Number of field variables override.
verbose	logical	in	optional	Trigger verbose output.

Call graph

compute_local_dt_forest

Compute this realm's local stability-limited dt (no MPI reduction).

Invoked by forest%compute_global_dt during the min reduction across all realms in the forest. The reduction itself is the orchestrator's job; this method computes only the value local to self. Compute this realm's local stability-limited dt (no MPI reduction).

subroutine compute_local_dt_forest(self, dt_local)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	in		The realm.
dt_local	real(kind=R8P)	out		Local stability-limited dt.

Call graph

advance_one_step_forest

Advance this realm by one full timestep of size dt.

Invoked by forest%evolve_one_step once per realm per timestep. Owns the integration itself, i.e. everything that turns q at time t into q at time t + dt.

subroutine advance_one_step_forest(self, dt)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The realm.
dt	real(kind=R8P)	in		Timestep size from the forest's global reduction.

Call graph

open_step_forest

Per-step prologue on the multi-realm path: set dt, init RK stages.

Mirrors the head of integrate_rk_ssp: external-field prelude (if active), rk%initialize_stages(q=self%q), and the per-step time bookkeeping advance_one_step_forest does inline (it increment, dt cap for time_max, self%time%dt update). Time advance and progress print run in close_step_forest, mirroring the legacy ordering.

subroutine open_step_forest(self, dt)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The realm.
dt	real(kind=R8P)	in		Timestep size from the forest.

Call graph

begin_stage_forest

Begin integrator stage k on the multi-realm path (FNL).

Mirrors the FIRST line of integrate_rk_ssp's substage body: rk_fnl%compute_stage(s=k, dt=self%time%dt [, phi_gpu=ib_fnl%phi_gpu]). This populates rk_fnl%q_rk_gpu(:,:,:,:,:,k) from previously computed substages and from self%q_gpu, and publishes the stage buffer to peers by setting self%stage_active = k. No ghost reads, no peer-realm access — peer realms may not yet have opened their stage-k buffer when this fires.

subroutine begin_stage_forest(self, k, K_total, dt, realm)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The realm.
k	integer(kind=I4P)	in		Stage index (1..K_total).
K_total	integer(kind=I4P)	in		Forest-wide stage count for this step.
dt	real(kind=R8P)	in		Timestep size from the forest.
realm	class(realm_object)	inout	target, optional	Sibling realms (contract parity).

Call graph

end_stage_forest

Close integrator stage k: residuals + stage assignment in one sweep (FNL).

This is the FNL forest's Phase 3 TBP. Inter-realm seam ghost cells on rk_fnl%q_rk_gpu(:,...,k) are already filled by Phase 2 (which called fill_seam_from_peer_forest on this realm and its peers), so compute_residuals_dev reads valid halo data and rk_fnl%assign_stage's in-place overwrite of the stage interior no longer races with peer reads.

realm accepted on contract for parity but unused: the seam has already been refreshed by the forest. Reflux for FV is not yet implemented on the FNL side (the FV residual path is commented out; compute_residuals_fv_centered_dev is a follow-up port).

subroutine end_stage_forest(self, k, K_total, dt, realm, flux_register)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The realm.
k	integer(kind=I4P)	in		Stage index (1..K_total).
K_total	integer(kind=I4P)	in		Forest-wide stage count for this step.
dt	real(kind=R8P)	in		Timestep size from the forest.
realm	class(realm_object)	inout	target, optional	Sibling realms (FNL parity only; unused).
flux_register	class(flux_register_object)	inout	optional	Forest's flux register for FV reflux.

Call graph

close_step_forest

Per-step epilogue on the multi-realm path: q assembly, BC, div-clean, residual save, coil source refresh, time advance, progress print (FNL).

subroutine close_step_forest(self, dt)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The realm.
dt	real(kind=R8P)	in		Timestep size from the forest.

Call graph

fill_seam_from_peer_forest

FNL twin of prism_cpu_object%fill_seam_from_peer_forest. Walks the host-side row-range bookkeeping (seam_local_peer_row_start/count, populated by build_seam_local_map on the host), then dispatches an OpenACC kernel that reads peer's GPU buffer at peer-INTERIOR coords (FNL layout (b,i,j,k,v)) and writes self's GPU buffer at recv-side coords.

subroutine fill_seam_from_peer_forest(self, peer, p_idx)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout
peer	class(realm_object)	in	target
p_idx	integer(kind=I4P)	in

Call graph

after_topology_build_forest

Propagate the freshly-built host seam maps and per-peer buffers to device-resident counterparts on field_fnl%maps. Invoked by the forest at the end of populate_inter_realm_topology AFTER build_seam_local_map has populated self%adam%maps%seam_local_*.

subroutine after_topology_build_forest(self)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout

Call graph

apply_reflux_to_stage_forest

PRISM-FNL override of the Berger-Colella reflux correction TBP.

FV reflux is not yet implemented on the FNL side — the FNL FV residual path (compute_residuals_fv_centered_dev) is a follow-up port and currently does NOT accumulate fluxes into the register. The override is therefore a deliberate no-op: with an empty flux register on the FNL side (or with nfaces == 0 for a single-realm FNL forest), there is nothing to correct.

α.r1 cadence (forward-consistency gate): the body returns immediately for stage /= self%rk%nrk. Under the current no-op body this is observationally identical to the previous unconditional return, but it expresses the α.r1 contract explicitly: when the FNL FV residual path is ported, the body grows into the OpenACC twin of prism_cpu_object%apply_reflux_to_stage_forest — walk flux_register%face(:) for entries where coarse_realm == self%realm_index and write the per-cell correction into self%rk_fnl%q_rk_gpu(:, b, i, j, k, stage) under a !$acc parallel loop — and that twin must fire exactly once per realm per step at the realm's final RK substage, reading the register's collapsed third-axis (:,:,1) bucket.

subroutine apply_reflux_to_stage_forest(self, stage, dt, flux_register)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The realm.
stage	integer(kind=I4P)	in		Integrator stage 1..K_total.
dt	real(kind=R8P)	in		Time step.
flux_register	class(flux_register_object)	in		Forest's flux register.

Call graph

post_step_forest

Run PRISM-FNL's per-timestep post-step work: state IO, energy diagnostics, max-divergence diagnostics.

Invoked by forest%post_step. v1 implementation is the verbatim post- step block formerly inline in simulate — every action runs every step, since today's cadence is enforced inside the save_* routines themselves (e.g. save_simulation_data honours io%it_save). The do_* flags are signature-only for now: when the forest takes over cadence the flags will gate the individual calls. For now they are accepted but unused, preserving present-day behavior bit-for-bit.

dt, t, it are not consumed by the current body; they are on the contract so the forest can supply them once it owns time-state (today they are still read from the time module singleton).

Optional realm(:): forwarded to save_simulation_data and update_ghost for the dummy-argument inter-realm halo refresh path.

subroutine post_step_forest(self, dt, t, it, do_save_state, do_save_residuals, do_save_restart, do_amr, realm)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The realm.
dt	real(kind=R8P)	in		Timestep size just advanced.
t	real(kind=R8P)	in		Simulation time after the advance.
it	integer(kind=I4P)	in		Iteration index after the advance.
do_save_state	logical	in	optional	Save state output this step.
do_save_residuals	logical	in	optional	Save residuals output this step.
do_save_restart	logical	in	optional	Save restart dump this step.
do_amr	logical	in	optional	Run AMR update this step.
realm	class(realm_object)	inout	target, optional	Sibling realms for inter-realm halo refresh.

Call graph

compute_dt

Compute the global stability-limited dt and store it on self%time%dt.

Body delegates the local computation to compute_local_dt_forest (orchestrator contract method), then performs the legacy MPI_ALLREDUCE on MPI_COMM_WORLD for backward compatibility with simulate. The forest's compute_global_dt performs its own reduction, possibly on a per-realm sub-comm; the redundancy disappears once the legacy compute_dt is retired.

subroutine compute_dt(self)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The equation.

Call graph

compute_energy

Compute energy.

subroutine compute_energy(self)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The equation.

Call graph

compute_energy_error

Compute energy error.

subroutine compute_energy_error(self)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The equation.

compute_max_divergence

Compute maximum divergence.

subroutine compute_max_divergence(self)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The equation.

Call graph

impose_ct_correction

Impose Constrained Transport Correction on vectorial variable q(ivar:ivar+2). Note that self%divergence memory is used as buffer, be carefull.

subroutine impose_ct_correction(self, ivar)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The equation.
ivar	integer(kind=I4P)	in		Variable (start) index in q.

Call graph

impose_div_free

Impose divergence-free property.

subroutine impose_div_free(self)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	inout		The equation.

Call graph

Functions

stages_per_step_forest

Number of integrator stages this realm exposes per step (FNL).

For the multi-realm path the forest drives the stage loop, so it needs to know K up front. Currently only runge-kutta-ssp-* is split into per-stage TBPs (begin_stage_forest / end_stage_forest); for RK realms K = rk%nrk. Other integrators (Yoshida, Leapfrog, Blanes-Moan, CFM) will error-stop on the multi-realm path until they are split as well.

Returns: integer(kind=I4P)

function stages_per_step_forest(self) result(K)

Arguments

Name	Type	Intent	Attributes	Description
self	class(prism_fnl_object)	in		The realm.

Call graph