Exemplo n.º 1
0
    def get_kernel(self, with_scaling, for_benchmark=False):
        from cgen import \
                Pointer, POD, Value, ArrayOf, \
                Module, FunctionDeclaration, FunctionBody, Block, \
                Line, Define, Include, \
                Initializer, If, For, Statement, Assign, \
                ArrayInitializer

        from cgen import dtype_to_ctype
        from cgen.cuda import CudaShared, CudaConstant, CudaGlobal

        discr = self.discr
        d = discr.dimensions
        dims = range(d)
        given = self.plan.given

        float_type = given.float_type

        f_decl = CudaGlobal(FunctionDeclaration(Value("void", "apply_el_local_mat_smem_mat"),
            [
                Pointer(POD(float_type, "out_vector")),
                Pointer(POD(numpy.uint8, "gmem_matrix")),
                Pointer(POD(float_type, "debugbuf")),
                POD(numpy.uint32, "microblock_count"),
                ]
            ))

        cmod = Module([
                Include("pycuda-helpers.hpp"),
                Line(),
                Value("texture<fp_tex_%s, 1, cudaReadModeElementType>"
                    % dtype_to_ctype(float_type),
                    "in_vector_tex"),
                ])
        if with_scaling:
            cmod.append(
                Value("texture<fp_tex_%s, 1, cudaReadModeElementType>"
                    % dtype_to_ctype(float_type),
                    "scaling_tex"),
                )

        par = self.plan.parallelism

        cmod.extend([
                Line(),
                Define("DIMENSIONS", discr.dimensions),
                Define("DOFS_PER_EL", given.dofs_per_el()),
                Define("PREIMAGE_DOFS_PER_EL", self.plan.preimage_dofs_per_el),
                Line(),
                Define("SEGMENT_DOF", "threadIdx.x"),
                Define("PAR_MB_NR", "threadIdx.y"),
                Line(),
                Define("MB_SEGMENT", "blockIdx.x"),
                Define("MACROBLOCK_NR", "blockIdx.y"),
                Line(),
                Define("DOFS_PER_SEGMENT", self.plan.segment_size),
                Define("SEGMENTS_PER_MB", self.plan.segments_per_microblock()),
                Define("ALIGNED_DOFS_PER_MB", given.microblock.aligned_floats),
                Define("ALIGNED_PREIMAGE_DOFS_PER_MB",
                    self.plan.aligned_preimage_dofs_per_microblock),
                Define("MB_EL_COUNT", given.microblock.elements),
                Line(),
                Define("PAR_MB_COUNT", par.parallel),
                Define("INLINE_MB_COUNT", par.inline),
                Define("SEQ_MB_COUNT", par.serial),
                Line(),
                Define("THREAD_NUM", "(SEGMENT_DOF+PAR_MB_NR*DOFS_PER_SEGMENT)"),
                Define("COALESCING_THREAD_COUNT", "(PAR_MB_COUNT*DOFS_PER_SEGMENT)"),
                Line(),
                Define("MB_DOF_BASE", "(MB_SEGMENT*DOFS_PER_SEGMENT)"),
                Define("MB_DOF", "(MB_DOF_BASE+SEGMENT_DOF)"),
                Define("GLOBAL_MB_NR_BASE",
                    "(MACROBLOCK_NR*PAR_MB_COUNT*INLINE_MB_COUNT*SEQ_MB_COUNT)"),
                Define("GLOBAL_MB_NR",
                    "(GLOBAL_MB_NR_BASE"
                    "+ (seq_mb_number*PAR_MB_COUNT + PAR_MB_NR)*INLINE_MB_COUNT)"),
                Define("GLOBAL_MB_DOF_BASE", "(GLOBAL_MB_NR*ALIGNED_DOFS_PER_MB)"),
                Define("GLOBAL_MB_PREIMG_DOF_BASE", "(GLOBAL_MB_NR*ALIGNED_PREIMAGE_DOFS_PER_MB)"),
                Line(),
                Define("MATRIX_COLUMNS", self.plan.gpu_matrix_columns()),
                Define("MATRIX_SEGMENT_FLOATS", self.plan.gpu_matrix_block_floats()),
                Define("MATRIX_SEGMENT_BYTES",
                    "(MATRIX_SEGMENT_FLOATS*%d)" % given.float_size()),

                Line(),
                CudaShared(ArrayOf(POD(float_type, "smem_matrix"),
                    "MATRIX_SEGMENT_FLOATS")),
                CudaShared(
                    ArrayOf(
                        ArrayOf(
                            ArrayOf(
                                POD(float_type, "dof_buffer"),
                                "PAR_MB_COUNT"),
                            "INLINE_MB_COUNT"),
                        "DOFS_PER_SEGMENT"),
                    ),
                CudaShared(POD(numpy.uint16, "segment_start_el")),
                CudaShared(POD(numpy.uint16, "segment_stop_el")),
                CudaShared(POD(numpy.uint16, "segment_el_count")),
                Line(),
                ArrayInitializer(
                        CudaConstant(
                            ArrayOf(
                                POD(numpy.uint32, "segment_start_el_lookup"),
                            "SEGMENTS_PER_MB")),
                        [(chk*self.plan.segment_size)//given.dofs_per_el()
                            for chk in range(self.plan.segments_per_microblock())]
                        ),
                ArrayInitializer(
                        CudaConstant(
                            ArrayOf(
                                POD(numpy.uint32, "segment_stop_el_lookup"),
                            "SEGMENTS_PER_MB")),
                        [min(given.microblock.elements,
                            (chk*self.plan.segment_size+self.plan.segment_size-1)
                                //given.dofs_per_el()+1)
                            for chk in range(self.plan.segments_per_microblock())]
                        ),
                ])

        S = Statement
        f_body = Block()

        f_body.extend_log_block("calculate this dof's element", [
            Initializer(POD(numpy.uint8, "mb_el"),
                "MB_DOF/DOFS_PER_EL") ])

        if self.plan.use_prefetch_branch:
            f_body.extend_log_block("calculate segment responsibility data", [
                If("THREAD_NUM==0",
                    Block([
                        Assign("segment_start_el", "segment_start_el_lookup[MB_SEGMENT]"),
                        Assign("segment_stop_el", "segment_stop_el_lookup[MB_SEGMENT]"),
                        Assign("segment_el_count", "segment_stop_el-segment_start_el"),
                        ])
                    ),
                S("__syncthreads()")
                ])

        from hedge.backends.cuda.tools import get_load_code
        f_body.extend(
            get_load_code(
                dest="smem_matrix",
                base=("gmem_matrix + MB_SEGMENT*MATRIX_SEGMENT_BYTES"),
                bytes="MATRIX_SEGMENT_BYTES",
                descr="load matrix segment")
            +[S("__syncthreads()")]
            )

        # ---------------------------------------------------------------------
        def get_batched_fetch_mat_mul_code(el_fetch_count):
            result = []
            dofs = range(self.plan.preimage_dofs_per_el)

            for load_segment_start in range(0, self.plan.preimage_dofs_per_el,
                    self.plan.segment_size):
                result.extend(
                        [S("__syncthreads()")]
                        +[Assign(
                            "dof_buffer[PAR_MB_NR][%d][SEGMENT_DOF]" % inl,
                            "fp_tex1Dfetch(in_vector_tex, "
                            "GLOBAL_MB_PREIMG_DOF_BASE"
                            " + %d*ALIGNED_PREIMAGE_DOFS_PER_MB"
                            " + (segment_start_el)*PREIMAGE_DOFS_PER_EL + %d + SEGMENT_DOF)"
                            % (inl, load_segment_start)
                            )
                        for inl in range(par.inline)]
                        +[S("__syncthreads()"),
                        Line(),
                        ])

                for dof in dofs[load_segment_start:load_segment_start+self.plan.segment_size]:
                    for inl in range(par.inline):
                        result.append(
                                S("result%d += "
                                    "smem_matrix[SEGMENT_DOF*MATRIX_COLUMNS + %d]"
                                    "*"
                                    "dof_buffer[PAR_MB_NR][%d][%d]"
                                    % (inl, dof, inl, dof-load_segment_start))
                                )
                result.append(Line())
            return result

        from hedge.backends.cuda.tools import unroll
        def get_direct_tex_mat_mul_code():
            return (
                    [POD(float_type, "fof%d" % inl) for inl in range(par.inline)]
                    + [POD(float_type, "lm"), Line()]
                    + unroll(
                        lambda j: [
                        Assign("fof%d" % inl,
                            "fp_tex1Dfetch(in_vector_tex, "
                            "GLOBAL_MB_PREIMG_DOF_BASE"
                            " + %(inl)d * ALIGNED_PREIMAGE_DOFS_PER_MB"
                            " + mb_el*PREIMAGE_DOFS_PER_EL+%(j)s)"
                            % {"j":j, "inl":inl, "row": "SEGMENT_DOF"},)
                        for inl in range(par.inline)
                        ]+[
                        Assign("lm",
                            "smem_matrix["
                            "%(row)s*MATRIX_COLUMNS + %(j)s]"
                            % {"j":j, "row": "SEGMENT_DOF"},
                            )
                        ]+[
                        S("result%(inl)d += fof%(inl)d*lm" % {"inl":inl})
                        for inl in range(par.inline)
                        ],
                        total_number=self.plan.preimage_dofs_per_el,
                        max_unroll=self.plan.max_unroll)
                    + [Line()])

        def get_mat_mul_code(el_fetch_count):
            if el_fetch_count == 1:
                return get_batched_fetch_mat_mul_code(el_fetch_count)
            else:
                return get_direct_tex_mat_mul_code()

        def mat_mul_outer_loop(fetch_count):
            if with_scaling:
                inv_jac_multiplier = ("fp_tex1Dfetch(scaling_tex,"
                        "(GLOBAL_MB_NR + %(inl)d)*MB_EL_COUNT + mb_el)")
            else:
                inv_jac_multiplier = "1"

            write_condition = "MB_DOF < DOFS_PER_EL*MB_EL_COUNT"
            if self.with_index_check:
                write_condition += " && GLOBAL_MB_NR < microblock_count"
            return For("unsigned short seq_mb_number = 0",
                "seq_mb_number < SEQ_MB_COUNT",
                "++seq_mb_number",
                Block([
                    Initializer(POD(float_type, "result%d" % inl), 0)
                    for inl in range(par.inline)
                    ]+[Line()]
                    +get_mat_mul_code(fetch_count)
                    +[
                    If(write_condition,
                        Block([
                            Assign(
                                "out_vector[GLOBAL_MB_DOF_BASE"
                                " + %d*ALIGNED_DOFS_PER_MB"
                                " + MB_DOF]" % inl,
                                "result%d * %s" % (inl, (inv_jac_multiplier % {"inl":inl}))
                                )
                            for inl in range(par.inline)
                            ])
                        )
                    ])
                )

        if self.plan.use_prefetch_branch:
            from cgen import make_multiple_ifs
            f_body.append(make_multiple_ifs([
                    ("segment_el_count == %d" % fetch_count,
                        mat_mul_outer_loop(fetch_count))
                    for fetch_count in
                    range(1, self.plan.max_elements_touched_by_segment()+1)]
                    ))
        else:
            f_body.append(mat_mul_outer_loop(0))

        # finish off ----------------------------------------------------------
        cmod.append(FunctionBody(f_decl, f_body))

        if not for_benchmark and "cuda_dump_kernels" in discr.debug:
            from hedge.tools import open_unique_debug_file
            open_unique_debug_file(self.plan.debug_name, ".cu").write(str(cmod))

        mod = SourceModule(cmod,
                keep="cuda_keep_kernels" in discr.debug,
                #options=["--maxrregcount=12"]
                )

        func = mod.get_function("apply_el_local_mat_smem_mat")

        if self.plan.debug_name in discr.debug:
            print "%s: lmem=%d smem=%d regs=%d" % (
                    self.plan.debug_name,
                    func.local_size_bytes,
                    func.shared_size_bytes,
                    func.num_regs)

        in_vector_texref = mod.get_texref("in_vector_tex")
        texrefs = [in_vector_texref]

        if with_scaling:
            scaling_texref = mod.get_texref("scaling_tex")
            texrefs.append(scaling_texref)
        else:
            scaling_texref = None

        func.prepare(
                "PPPI",
                block=(self.plan.segment_size, self.plan.parallelism.parallel, 1),
                texrefs=texrefs)

        return func, in_vector_texref, scaling_texref
Exemplo n.º 2
0
    def get_kernel(self, fdata, ilist_data, for_benchmark):
        from cgen.cuda import CudaShared, CudaGlobal
        from pycuda.tools import dtype_to_ctype

        discr = self.discr
        given = self.plan.given
        fplan = self.plan
        d = discr.dimensions
        dims = range(d)

        elgroup, = discr.element_groups

        float_type = given.float_type

        f_decl = CudaGlobal(FunctionDeclaration(Value("void", "apply_flux"),
            [
                Pointer(POD(float_type, "debugbuf")),
                Pointer(POD(numpy.uint8, "gmem_facedata")),
                ]+[
                Pointer(POD(float_type, "gmem_fluxes_on_faces%d" % flux_nr))
                for flux_nr in range(len(self.fluxes))
                ]
            ))

        cmod = Module()
        cmod.append(Include("pycuda-helpers.hpp"))

        for dep_expr in self.all_deps:
            cmod.extend([
                Value("texture<%s, 1, cudaReadModeElementType>"
                    % dtype_to_ctype(float_type, with_fp_tex_hack=True),
                    "field%d_tex" % self.dep_to_index[dep_expr])
                ])

        if fplan.flux_count != len(self.fluxes):
            from warnings import warn
            warn("Flux count in flux execution plan different from actual flux count.\n"
                    "You may want to specify the tune_for= kwarg in the Discretization\n"
                    "constructor.")

        cmod.extend([
            Line(),
            Typedef(POD(float_type, "value_type")),
            Line(),
            flux_header_struct(float_type, discr.dimensions),
            Line(),
            face_pair_struct(float_type, discr.dimensions),
            Line(),
            Define("DIMENSIONS", discr.dimensions),
            Define("DOFS_PER_FACE", fplan.dofs_per_face),
            Define("THREADS_PER_FACE", fplan.threads_per_face()),
            Line(),
            Define("CONCURRENT_FACES", fplan.parallel_faces),
            Define("BLOCK_MB_COUNT", fplan.mbs_per_block),
            Line(),
            Define("FACEDOF_NR", "threadIdx.x"),
            Define("BLOCK_FACE", "threadIdx.y"),
            Line(),
            Define("FLUX_COUNT", len(self.fluxes)),
            Line(),
            Define("THREAD_NUM", "(FACEDOF_NR + BLOCK_FACE*THREADS_PER_FACE)"),
            Define("THREAD_COUNT", "(THREADS_PER_FACE*CONCURRENT_FACES)"),
            Define("COALESCING_THREAD_COUNT",
                "(THREAD_COUNT < 0x10 ? THREAD_COUNT : THREAD_COUNT & ~0xf)"),
            Line(),
            Define("DATA_BLOCK_SIZE", fdata.block_bytes),
            Define("ALIGNED_FACE_DOFS_PER_MB", fplan.aligned_face_dofs_per_microblock()),
            Define("ALIGNED_FACE_DOFS_PER_BLOCK",
                "(ALIGNED_FACE_DOFS_PER_MB*BLOCK_MB_COUNT)"),
            Line(),
            Define("FOF_BLOCK_BASE", "(blockIdx.x*ALIGNED_FACE_DOFS_PER_BLOCK)"),
            Line(),
            ] + ilist_data.code + [
            Line(),
            Value("texture<index_list_entry_t, 1, cudaReadModeElementType>",
                "tex_index_lists"),
            Line(),
            fdata.struct,
            Line(),
            CudaShared(Value("flux_data", "data")),
            ])

        if not fplan.direct_store:
            cmod.extend([
                CudaShared(
                    ArrayOf(
                        ArrayOf(
                            POD(float_type, "smem_fluxes_on_faces"),
                            "FLUX_COUNT"),
                        "ALIGNED_FACE_DOFS_PER_MB*BLOCK_MB_COUNT")
                    ),
                Line(),
                ])

        S = Statement
        f_body = Block()

        from hedge.backends.cuda.tools import get_load_code

        f_body.extend(get_load_code(
            dest="&data",
            base="gmem_facedata + blockIdx.x*DATA_BLOCK_SIZE",
            bytes="sizeof(flux_data)",
            descr="load face_pair data")
            +[S("__syncthreads()"), Line() ])

        def get_flux_code(flux_writer):
            flux_code = Block([])

            flux_code.extend([
                Initializer(Pointer(
                    Value("face_pair", "fpair")),
                    "data.facepairs+fpair_nr"),
                Initializer(
                    MaybeUnused(POD(numpy.uint32, "a_index")),
                    "fpair->a_base + tex1Dfetch(tex_index_lists, "
                    "fpair->a_ilist_index + FACEDOF_NR)"),
                Initializer(
                    MaybeUnused(POD(numpy.uint32, "b_index")),
                    "fpair->b_base + tex1Dfetch(tex_index_lists, "
                    "fpair->b_ilist_index + FACEDOF_NR)"),
                Line(),
                flux_writer(),
                Line(),
                S("fpair_nr += CONCURRENT_FACES")
                ])

            return flux_code

        flux_computation = Block([
            Comment("fluxes for dual-sided (intra-block) interior face pairs"),
            While("fpair_nr < data.header.same_facepairs_end",
                get_flux_code(lambda:
                    self.write_interior_flux_code(True))
                ),
            Line(),
            Comment("work around nvcc assertion failure"),
            S("fpair_nr+=1"),
            S("fpair_nr-=1"),
            Line(),
            Comment("fluxes for single-sided (inter-block) interior face pairs"),
            While("fpair_nr < data.header.diff_facepairs_end",
                get_flux_code(lambda:
                    self.write_interior_flux_code(False))
                ),
            Line(),
            Comment("fluxes for single-sided boundary face pairs"),
            While("fpair_nr < data.header.bdry_facepairs_end",
                get_flux_code(
                    lambda: self.write_boundary_flux_code(for_benchmark))
                ),
            ])

        f_body.extend_log_block("compute the fluxes", [
            Initializer(POD(numpy.uint32, "fpair_nr"), "BLOCK_FACE"),
            If("FACEDOF_NR < DOFS_PER_FACE", flux_computation)
            ])

        if not fplan.direct_store:
            f_body.extend([
                Line(),
                S("__syncthreads()"),
                Line()
                ])

            f_body.extend_log_block("store fluxes", [
                    #Assign("debugbuf[blockIdx.x]", "FOF_BLOCK_BASE"),
                    #Assign("debugbuf[0]", "FOF_BLOCK_BASE"),
                    #Assign("debugbuf[0]", "sizeof(face_pair)"),
                    For("unsigned word_nr = THREAD_NUM",
                        "word_nr < ALIGNED_FACE_DOFS_PER_MB*BLOCK_MB_COUNT",
                        "word_nr += COALESCING_THREAD_COUNT",
                        Block([Assign(
                            "gmem_fluxes_on_faces%d[FOF_BLOCK_BASE+word_nr]" % flux_nr,
                            "smem_fluxes_on_faces[%d][word_nr]" % flux_nr)
                            for flux_nr in range(len(self.fluxes))]
                           #+[If("isnan(smem_fluxes_on_faces[%d][word_nr])" % flux_nr,
                               #Block([
                                   #Assign("debugbuf[blockIdx.x]", "word_nr"),
                                   #])
                               #)
                            #for flux_nr in range(len(self.fluxes))]
                        )
                    )
                    ])
        if False:
            f_body.extend([
                    Assign("debugbuf[blockIdx.x*96+32+BLOCK_FACE*32+threadIdx.x]", "fpair_nr"),
                    Assign("debugbuf[blockIdx.x*96+16]", "data.header.same_facepairs_end"),
                    Assign("debugbuf[blockIdx.x*96+17]", "data.header.diff_facepairs_end"),
                    Assign("debugbuf[blockIdx.x*96+18]", "data.header.bdry_facepairs_end"),
                    ]
                    )

        # finish off ----------------------------------------------------------
        cmod.append(FunctionBody(f_decl, f_body))

        if not for_benchmark and "cuda_dump_kernels" in discr.debug:
            from hedge.tools import open_unique_debug_file
            open_unique_debug_file("flux_gather", ".cu").write(str(cmod))

        #from pycuda.tools import allow_user_edit
        mod = SourceModule(
                #allow_user_edit(cmod, "kernel.cu", "the flux kernel"),
                cmod,
                keep="cuda_keep_kernels" in discr.debug)
        expr_to_texture_map = dict(
                (dep_expr, mod.get_texref(
                    "field%d_tex" % self.dep_to_index[dep_expr]))
                for dep_expr in self.all_deps)

        index_list_texref = mod.get_texref("tex_index_lists")
        index_list_texref.set_address(
                ilist_data.device_memory,
                ilist_data.bytes)
        index_list_texref.set_format(
                cuda.dtype_to_array_format(ilist_data.type), 1)
        index_list_texref.set_flags(cuda.TRSF_READ_AS_INTEGER)

        func = mod.get_function("apply_flux")
        block = (fplan.threads_per_face(), fplan.parallel_faces, 1)
        func.prepare(
                (2+len(self.fluxes))*"P",
                texrefs=expr_to_texture_map.values()
                + [index_list_texref])

        if "cuda_flux" in discr.debug:
            print "flux: lmem=%d smem=%d regs=%d" % (
                    func.local_size_bytes,
                    func.shared_size_bytes,
                    func.num_regs)

        return block, func, expr_to_texture_map
Exemplo n.º 3
0
    def get_kernel(self, fdata, ilist_data, for_benchmark):
        from cgen.cuda import CudaShared, CudaGlobal
        from pycuda.tools import dtype_to_ctype

        discr = self.discr
        given = self.plan.given
        fplan = self.plan
        d = discr.dimensions
        dims = range(d)

        elgroup, = discr.element_groups

        float_type = given.float_type

        f_decl = CudaGlobal(
            FunctionDeclaration(Value("void", "apply_flux"), [
                Pointer(POD(float_type, "debugbuf")),
                Pointer(POD(numpy.uint8, "gmem_facedata")),
            ] + [
                Pointer(POD(float_type, "gmem_fluxes_on_faces%d" % flux_nr))
                for flux_nr in range(len(self.fluxes))
            ]))

        cmod = Module()
        cmod.append(Include("pycuda-helpers.hpp"))

        for dep_expr in self.all_deps:
            cmod.extend([
                Value(
                    "texture<%s, 1, cudaReadModeElementType>" %
                    dtype_to_ctype(float_type, with_fp_tex_hack=True),
                    "field%d_tex" % self.dep_to_index[dep_expr])
            ])

        if fplan.flux_count != len(self.fluxes):
            from warnings import warn
            warn(
                "Flux count in flux execution plan different from actual flux count.\n"
                "You may want to specify the tune_for= kwarg in the Discretization\n"
                "constructor.")

        cmod.extend([
            Line(),
            Typedef(POD(float_type, "value_type")),
            Line(),
            flux_header_struct(float_type, discr.dimensions),
            Line(),
            face_pair_struct(float_type, discr.dimensions),
            Line(),
            Define("DIMENSIONS", discr.dimensions),
            Define("DOFS_PER_FACE", fplan.dofs_per_face),
            Define("THREADS_PER_FACE", fplan.threads_per_face()),
            Line(),
            Define("CONCURRENT_FACES", fplan.parallel_faces),
            Define("BLOCK_MB_COUNT", fplan.mbs_per_block),
            Line(),
            Define("FACEDOF_NR", "threadIdx.x"),
            Define("BLOCK_FACE", "threadIdx.y"),
            Line(),
            Define("FLUX_COUNT", len(self.fluxes)),
            Line(),
            Define("THREAD_NUM", "(FACEDOF_NR + BLOCK_FACE*THREADS_PER_FACE)"),
            Define("THREAD_COUNT", "(THREADS_PER_FACE*CONCURRENT_FACES)"),
            Define(
                "COALESCING_THREAD_COUNT",
                "(THREAD_COUNT < 0x10 ? THREAD_COUNT : THREAD_COUNT & ~0xf)"),
            Line(),
            Define("DATA_BLOCK_SIZE", fdata.block_bytes),
            Define("ALIGNED_FACE_DOFS_PER_MB",
                   fplan.aligned_face_dofs_per_microblock()),
            Define("ALIGNED_FACE_DOFS_PER_BLOCK",
                   "(ALIGNED_FACE_DOFS_PER_MB*BLOCK_MB_COUNT)"),
            Line(),
            Define("FOF_BLOCK_BASE",
                   "(blockIdx.x*ALIGNED_FACE_DOFS_PER_BLOCK)"),
            Line(),
        ] + ilist_data.code + [
            Line(),
            Value("texture<index_list_entry_t, 1, cudaReadModeElementType>",
                  "tex_index_lists"),
            Line(),
            fdata.struct,
            Line(),
            CudaShared(Value("flux_data", "data")),
        ])

        if not fplan.direct_store:
            cmod.extend([
                CudaShared(
                    ArrayOf(
                        ArrayOf(POD(float_type, "smem_fluxes_on_faces"),
                                "FLUX_COUNT"),
                        "ALIGNED_FACE_DOFS_PER_MB*BLOCK_MB_COUNT")),
                Line(),
            ])

        S = Statement
        f_body = Block()

        from hedge.backends.cuda.tools import get_load_code

        f_body.extend(
            get_load_code(dest="&data",
                          base="gmem_facedata + blockIdx.x*DATA_BLOCK_SIZE",
                          bytes="sizeof(flux_data)",
                          descr="load face_pair data") +
            [S("__syncthreads()"), Line()])

        def get_flux_code(flux_writer):
            flux_code = Block([])

            flux_code.extend([
                Initializer(Pointer(Value("face_pair", "fpair")),
                            "data.facepairs+fpair_nr"),
                Initializer(
                    MaybeUnused(POD(numpy.uint32, "a_index")),
                    "fpair->a_base + tex1Dfetch(tex_index_lists, "
                    "fpair->a_ilist_index + FACEDOF_NR)"),
                Initializer(
                    MaybeUnused(POD(numpy.uint32, "b_index")),
                    "fpair->b_base + tex1Dfetch(tex_index_lists, "
                    "fpair->b_ilist_index + FACEDOF_NR)"),
                Line(),
                flux_writer(),
                Line(),
                S("fpair_nr += CONCURRENT_FACES")
            ])

            return flux_code

        flux_computation = Block([
            Comment("fluxes for dual-sided (intra-block) interior face pairs"),
            While("fpair_nr < data.header.same_facepairs_end",
                  get_flux_code(lambda: self.write_interior_flux_code(True))),
            Line(),
            Comment("work around nvcc assertion failure"),
            S("fpair_nr+=1"),
            S("fpair_nr-=1"),
            Line(),
            Comment(
                "fluxes for single-sided (inter-block) interior face pairs"),
            While("fpair_nr < data.header.diff_facepairs_end",
                  get_flux_code(lambda: self.write_interior_flux_code(False))),
            Line(),
            Comment("fluxes for single-sided boundary face pairs"),
            While(
                "fpair_nr < data.header.bdry_facepairs_end",
                get_flux_code(
                    lambda: self.write_boundary_flux_code(for_benchmark))),
        ])

        f_body.extend_log_block("compute the fluxes", [
            Initializer(POD(numpy.uint32, "fpair_nr"), "BLOCK_FACE"),
            If("FACEDOF_NR < DOFS_PER_FACE", flux_computation)
        ])

        if not fplan.direct_store:
            f_body.extend([Line(), S("__syncthreads()"), Line()])

            f_body.extend_log_block(
                "store fluxes",
                [
                    #Assign("debugbuf[blockIdx.x]", "FOF_BLOCK_BASE"),
                    #Assign("debugbuf[0]", "FOF_BLOCK_BASE"),
                    #Assign("debugbuf[0]", "sizeof(face_pair)"),
                    For(
                        "unsigned word_nr = THREAD_NUM",
                        "word_nr < ALIGNED_FACE_DOFS_PER_MB*BLOCK_MB_COUNT",
                        "word_nr += COALESCING_THREAD_COUNT",
                        Block([
                            Assign(
                                "gmem_fluxes_on_faces%d[FOF_BLOCK_BASE+word_nr]"
                                % flux_nr,
                                "smem_fluxes_on_faces[%d][word_nr]" % flux_nr)
                            for flux_nr in range(len(self.fluxes))
                        ]
                              #+[If("isnan(smem_fluxes_on_faces[%d][word_nr])" % flux_nr,
                              #Block([
                              #Assign("debugbuf[blockIdx.x]", "word_nr"),
                              #])
                              #)
                              #for flux_nr in range(len(self.fluxes))]
                              ))
                ])
        if False:
            f_body.extend([
                Assign("debugbuf[blockIdx.x*96+32+BLOCK_FACE*32+threadIdx.x]",
                       "fpair_nr"),
                Assign("debugbuf[blockIdx.x*96+16]",
                       "data.header.same_facepairs_end"),
                Assign("debugbuf[blockIdx.x*96+17]",
                       "data.header.diff_facepairs_end"),
                Assign("debugbuf[blockIdx.x*96+18]",
                       "data.header.bdry_facepairs_end"),
            ])

        # finish off ----------------------------------------------------------
        cmod.append(FunctionBody(f_decl, f_body))

        if not for_benchmark and "cuda_dump_kernels" in discr.debug:
            from hedge.tools import open_unique_debug_file
            open_unique_debug_file("flux_gather", ".cu").write(str(cmod))

        #from pycuda.tools import allow_user_edit
        mod = SourceModule(
            #allow_user_edit(cmod, "kernel.cu", "the flux kernel"),
            cmod,
            keep="cuda_keep_kernels" in discr.debug)
        expr_to_texture_map = dict(
            (dep_expr,
             mod.get_texref("field%d_tex" % self.dep_to_index[dep_expr]))
            for dep_expr in self.all_deps)

        index_list_texref = mod.get_texref("tex_index_lists")
        index_list_texref.set_address(ilist_data.device_memory,
                                      ilist_data.bytes)
        index_list_texref.set_format(
            cuda.dtype_to_array_format(ilist_data.type), 1)
        index_list_texref.set_flags(cuda.TRSF_READ_AS_INTEGER)

        func = mod.get_function("apply_flux")
        block = (fplan.threads_per_face(), fplan.parallel_faces, 1)
        func.prepare(
            (2 + len(self.fluxes)) * "P",
            texrefs=expr_to_texture_map.values() + [index_list_texref])

        if "cuda_flux" in discr.debug:
            print "flux: lmem=%d smem=%d regs=%d" % (
                func.local_size_bytes, func.shared_size_bytes, func.num_regs)

        return block, func, expr_to_texture_map
Exemplo n.º 4
0
    def get_kernel(self, diff_op_cls, elgroup, for_benchmark=False):
        from cgen import \
                Pointer, POD, Value, ArrayOf, \
                Module, FunctionDeclaration, FunctionBody, Block, \
                Line, Define, Include, \
                Initializer, If, For, Statement, Assign

        from cgen import dtype_to_ctype
        from cgen.cuda import CudaShared, CudaGlobal

        discr = self.discr
        d = discr.dimensions
        dims = range(d)
        given = self.plan.given

        par = self.plan.parallelism

        diffmat_data = self.gpu_diffmats(diff_op_cls, elgroup)
        elgroup, = discr.element_groups

        float_type = given.float_type

        f_decl = CudaGlobal(FunctionDeclaration(Value("void", "apply_diff_mat"),
            [Pointer(POD(numpy.uint8, "gmem_diff_rst_mat")),
                #Pointer(POD(float_type, "debugbuf")),
                ] + [Pointer(POD(float_type, "drst%d_global" % i)) for i in dims]
            ))

        rst_channels = given.devdata.make_valid_tex_channel_count(d)
        cmod = Module([
                Include("pycuda-helpers.hpp"),
                Line(),
                Value("texture<fp_tex_%s, 1, cudaReadModeElementType>"
                    % dtype_to_ctype(float_type),
                    "field_tex"),
                Line(),
                Define("DIMENSIONS", discr.dimensions),
                Define("DOFS_PER_EL", given.dofs_per_el()),
                Line(),
                Define("SEGMENT_DOF", "threadIdx.x"),
                Define("PAR_MB_NR", "threadIdx.y"),
                Line(),
                Define("MB_SEGMENT", "blockIdx.x"),
                Define("MACROBLOCK_NR", "blockIdx.y"),
                Line(),
                Define("DOFS_PER_SEGMENT", self.plan.segment_size),
                Define("SEGMENTS_PER_MB", self.plan.segments_per_microblock()),
                Define("ALIGNED_DOFS_PER_MB", given.microblock.aligned_floats),
                Define("ELS_PER_MB", given.microblock.elements),
                Line(),
                Define("PAR_MB_COUNT", par.parallel),
                Define("INLINE_MB_COUNT", par.inline),
                Define("SEQ_MB_COUNT", par.serial),
                Line(),
                Define("THREAD_NUM", "(SEGMENT_DOF+PAR_MB_NR*DOFS_PER_SEGMENT)"),
                Define("COALESCING_THREAD_COUNT", "(PAR_MB_COUNT*DOFS_PER_SEGMENT)"),
                Line(),
                Define("MB_DOF_BASE", "(MB_SEGMENT*DOFS_PER_SEGMENT)"),
                Define("MB_DOF", "(MB_DOF_BASE+SEGMENT_DOF)"),
                Define("GLOBAL_MB_NR_BASE",
                    "(MACROBLOCK_NR*PAR_MB_COUNT*INLINE_MB_COUNT*SEQ_MB_COUNT)"),
                Define("GLOBAL_MB_NR",
                    "(GLOBAL_MB_NR_BASE"
                    "+ (seq_mb_number*PAR_MB_COUNT + PAR_MB_NR)*INLINE_MB_COUNT)"),
                Define("GLOBAL_MB_DOF_BASE", "(GLOBAL_MB_NR*ALIGNED_DOFS_PER_MB)"),
                Line(),
                Define("DIFFMAT_SEGMENT_FLOATS", diffmat_data.block_floats),
                Define("DIFFMAT_SEGMENT_BYTES", "(DIFFMAT_SEGMENT_FLOATS*%d)"
                     % given.float_size()),
                Define("DIFFMAT_COLUMNS", diffmat_data.matrix_columns),
                Line(),
                CudaShared(ArrayOf(POD(float_type, "smem_diff_rst_mat"),
                    "DIFFMAT_COLUMNS*DOFS_PER_SEGMENT")),
                Line(),
                ])

        S = Statement
        f_body = Block()

        f_body.extend_log_block("calculate responsibility data", [
            Initializer(POD(numpy.uint16, "mb_el"),
                "MB_DOF/DOFS_PER_EL"),
            ])

        from hedge.backends.cuda.tools import get_load_code
        f_body.extend(
            get_load_code(
                dest="smem_diff_rst_mat",
                base="gmem_diff_rst_mat + MB_SEGMENT*DIFFMAT_SEGMENT_BYTES",
                bytes="DIFFMAT_SEGMENT_BYTES",
                descr="load diff mat segment")
            +[S("__syncthreads()"), Line()])

        # ---------------------------------------------------------------------
        def get_scalar_diff_code():
            code = []
            for inl in range(par.inline):
                for axis in dims:
                    code.append(
                        Initializer(POD(float_type, "d%drst%d" % (inl, axis)), 0))

            code.append(Line())

            def get_mat_entry(row, col, axis):
                return ("smem_diff_rst_mat["
                        "%(row)s*DIFFMAT_COLUMNS + %(axis)s*DOFS_PER_EL"
                        " + %(col)s"
                        "]" % {"row":row, "col":col, "axis":axis}
                        )

            tex_channels = ["x", "y", "z", "w"]
            from hedge.backends.cuda.tools import unroll
            code.extend(
                    [POD(float_type, "field_value%d" % inl)
                        for inl in range(par.inline)]
                    +[Line()]
                    +unroll(lambda j: [
                        Assign("field_value%d" % inl,
                            "fp_tex1Dfetch(field_tex, GLOBAL_MB_DOF_BASE + %d*ALIGNED_DOFS_PER_MB "
                            "+ mb_el*DOFS_PER_EL + %s)" % (inl, j)
                            )
                        for inl in range(par.inline)]
                        +[Line()]
                        +[S("d%drst%d += %s * field_value%d"
                            % (inl, axis, get_mat_entry("SEGMENT_DOF", j, axis), inl))
                        for axis in dims
                        for inl in range(par.inline)]
                        +[Line()],
                        given.dofs_per_el(), self.plan.max_unroll)
                    )

            store_code = Block()
            for inl in range(par.inline):
                for rst_axis in dims:
                    store_code.append(Assign(
                        "drst%d_global[GLOBAL_MB_DOF_BASE"
                        " + %d*ALIGNED_DOFS_PER_MB + MB_DOF]" % (rst_axis, inl),
                        "d%drst%d" % (inl, rst_axis),
                        ))

            code.append(If("MB_DOF < DOFS_PER_EL*ELS_PER_MB", store_code))

            return code

        f_body.extend([
            For("unsigned short seq_mb_number = 0",
                "seq_mb_number < SEQ_MB_COUNT",
                "++seq_mb_number",
                Block(get_scalar_diff_code()))
            ])

        # finish off ----------------------------------------------------------
        cmod.append(FunctionBody(f_decl, f_body))

        if not for_benchmark and "cuda_dump_kernels" in discr.debug:
            from hedge.tools import open_unique_debug_file
            open_unique_debug_file("diff", ".cu").write(str(cmod))

        mod = SourceModule(cmod,
                keep="cuda_keep_kernels" in discr.debug,
                #options=["--maxrregcount=10"]
                )

        field_texref = mod.get_texref("field_tex")

        func = mod.get_function("apply_diff_mat")
        func.prepare(
                discr.dimensions*[float_type] + ["P"],
                block=(self.plan.segment_size, par.parallel, 1),
                texrefs=[field_texref])

        if "cuda_diff" in discr.debug:
            print "diff: lmem=%d smem=%d regs=%d" % (
                    func.local_size_bytes,
                    func.shared_size_bytes,
                    func.num_regs)

        return func, field_texref
Exemplo n.º 5
0
    def get_kernel(self, diff_op_cls, elgroup, for_benchmark=False):
        from cgen import \
                Pointer, POD, Value, ArrayOf, \
                Module, FunctionDeclaration, FunctionBody, Block, \
                Line, Define, Include, \
                Initializer, If, For, Statement, Assign

        from cgen import dtype_to_ctype
        from cgen.cuda import CudaShared, CudaGlobal

        discr = self.discr
        d = discr.dimensions
        dims = range(d)
        given = self.plan.given

        par = self.plan.parallelism

        diffmat_data = self.gpu_diffmats(diff_op_cls, elgroup)
        elgroup, = discr.element_groups

        float_type = given.float_type

        f_decl = CudaGlobal(
            FunctionDeclaration(
                Value("void", "apply_diff_mat"),
                [
                    Pointer(POD(numpy.uint8, "gmem_diff_rst_mat")),
                    #Pointer(POD(float_type, "debugbuf")),
                ] +
                [Pointer(POD(float_type, "drst%d_global" % i)) for i in dims]))

        rst_channels = given.devdata.make_valid_tex_channel_count(d)
        cmod = Module([
            Include("pycuda-helpers.hpp"),
            Line(),
            Value(
                "texture<fp_tex_%s, 1, cudaReadModeElementType>" %
                dtype_to_ctype(float_type), "field_tex"),
            Line(),
            Define("DIMENSIONS", discr.dimensions),
            Define("DOFS_PER_EL", given.dofs_per_el()),
            Line(),
            Define("SEGMENT_DOF", "threadIdx.x"),
            Define("PAR_MB_NR", "threadIdx.y"),
            Line(),
            Define("MB_SEGMENT", "blockIdx.x"),
            Define("MACROBLOCK_NR", "blockIdx.y"),
            Line(),
            Define("DOFS_PER_SEGMENT", self.plan.segment_size),
            Define("SEGMENTS_PER_MB", self.plan.segments_per_microblock()),
            Define("ALIGNED_DOFS_PER_MB", given.microblock.aligned_floats),
            Define("ELS_PER_MB", given.microblock.elements),
            Line(),
            Define("PAR_MB_COUNT", par.parallel),
            Define("INLINE_MB_COUNT", par.inline),
            Define("SEQ_MB_COUNT", par.serial),
            Line(),
            Define("THREAD_NUM", "(SEGMENT_DOF+PAR_MB_NR*DOFS_PER_SEGMENT)"),
            Define("COALESCING_THREAD_COUNT",
                   "(PAR_MB_COUNT*DOFS_PER_SEGMENT)"),
            Line(),
            Define("MB_DOF_BASE", "(MB_SEGMENT*DOFS_PER_SEGMENT)"),
            Define("MB_DOF", "(MB_DOF_BASE+SEGMENT_DOF)"),
            Define(
                "GLOBAL_MB_NR_BASE",
                "(MACROBLOCK_NR*PAR_MB_COUNT*INLINE_MB_COUNT*SEQ_MB_COUNT)"),
            Define(
                "GLOBAL_MB_NR", "(GLOBAL_MB_NR_BASE"
                "+ (seq_mb_number*PAR_MB_COUNT + PAR_MB_NR)*INLINE_MB_COUNT)"),
            Define("GLOBAL_MB_DOF_BASE", "(GLOBAL_MB_NR*ALIGNED_DOFS_PER_MB)"),
            Line(),
            Define("DIFFMAT_SEGMENT_FLOATS", diffmat_data.block_floats),
            Define("DIFFMAT_SEGMENT_BYTES",
                   "(DIFFMAT_SEGMENT_FLOATS*%d)" % given.float_size()),
            Define("DIFFMAT_COLUMNS", diffmat_data.matrix_columns),
            Line(),
            CudaShared(
                ArrayOf(POD(float_type, "smem_diff_rst_mat"),
                        "DIFFMAT_COLUMNS*DOFS_PER_SEGMENT")),
            Line(),
        ])

        S = Statement
        f_body = Block()

        f_body.extend_log_block("calculate responsibility data", [
            Initializer(POD(numpy.uint16, "mb_el"), "MB_DOF/DOFS_PER_EL"),
        ])

        from hedge.backends.cuda.tools import get_load_code
        f_body.extend(
            get_load_code(
                dest="smem_diff_rst_mat",
                base="gmem_diff_rst_mat + MB_SEGMENT*DIFFMAT_SEGMENT_BYTES",
                bytes="DIFFMAT_SEGMENT_BYTES",
                descr="load diff mat segment") +
            [S("__syncthreads()"), Line()])

        # ---------------------------------------------------------------------
        def get_scalar_diff_code():
            code = []
            for inl in range(par.inline):
                for axis in dims:
                    code.append(
                        Initializer(POD(float_type, "d%drst%d" % (inl, axis)),
                                    0))

            code.append(Line())

            def get_mat_entry(row, col, axis):
                return ("smem_diff_rst_mat["
                        "%(row)s*DIFFMAT_COLUMNS + %(axis)s*DOFS_PER_EL"
                        " + %(col)s"
                        "]" % {
                            "row": row,
                            "col": col,
                            "axis": axis
                        })

            tex_channels = ["x", "y", "z", "w"]
            from hedge.backends.cuda.tools import unroll
            code.extend([
                POD(float_type, "field_value%d" % inl)
                for inl in range(par.inline)
            ] + [Line()] + unroll(
                lambda j: [
                    Assign(
                        "field_value%d" % inl,
                        "fp_tex1Dfetch(field_tex, GLOBAL_MB_DOF_BASE + %d*ALIGNED_DOFS_PER_MB "
                        "+ mb_el*DOFS_PER_EL + %s)" % (inl, j))
                    for inl in range(par.inline)
                ] + [Line()] + [
                    S("d%drst%d += %s * field_value%d" %
                      (inl, axis, get_mat_entry("SEGMENT_DOF", j, axis), inl))
                    for axis in dims for inl in range(par.inline)
                ] + [Line()], given.dofs_per_el(), self.plan.max_unroll))

            store_code = Block()
            for inl in range(par.inline):
                for rst_axis in dims:
                    store_code.append(
                        Assign(
                            "drst%d_global[GLOBAL_MB_DOF_BASE"
                            " + %d*ALIGNED_DOFS_PER_MB + MB_DOF]" %
                            (rst_axis, inl),
                            "d%drst%d" % (inl, rst_axis),
                        ))

            code.append(If("MB_DOF < DOFS_PER_EL*ELS_PER_MB", store_code))

            return code

        f_body.extend([
            For("unsigned short seq_mb_number = 0",
                "seq_mb_number < SEQ_MB_COUNT", "++seq_mb_number",
                Block(get_scalar_diff_code()))
        ])

        # finish off ----------------------------------------------------------
        cmod.append(FunctionBody(f_decl, f_body))

        if not for_benchmark and "cuda_dump_kernels" in discr.debug:
            from hedge.tools import open_unique_debug_file
            open_unique_debug_file("diff", ".cu").write(str(cmod))

        mod = SourceModule(
            cmod,
            keep="cuda_keep_kernels" in discr.debug,
            #options=["--maxrregcount=10"]
        )

        field_texref = mod.get_texref("field_tex")

        func = mod.get_function("apply_diff_mat")
        func.prepare(discr.dimensions * [float_type] + ["P"],
                     block=(self.plan.segment_size, par.parallel, 1),
                     texrefs=[field_texref])

        if "cuda_diff" in discr.debug:
            print "diff: lmem=%d smem=%d regs=%d" % (
                func.local_size_bytes, func.shared_size_bytes, func.num_regs)

        return func, field_texref
Exemplo n.º 6
0
    def get_kernel(self, with_scaling, for_benchmark=False):
        from cgen import \
                Pointer, POD, Value, ArrayOf, \
                Module, FunctionDeclaration, FunctionBody, Block, \
                Line, Define, Include, \
                Initializer, If, For, Statement, Assign, \
                ArrayInitializer

        from cgen import dtype_to_ctype
        from cgen.cuda import CudaShared, CudaConstant, CudaGlobal

        discr = self.discr
        d = discr.dimensions
        dims = range(d)
        given = self.plan.given

        float_type = given.float_type

        f_decl = CudaGlobal(
            FunctionDeclaration(Value("void", "apply_el_local_mat_smem_mat"), [
                Pointer(POD(float_type, "out_vector")),
                Pointer(POD(numpy.uint8, "gmem_matrix")),
                Pointer(POD(float_type, "debugbuf")),
                POD(numpy.uint32, "microblock_count"),
            ]))

        cmod = Module([
            Include("pycuda-helpers.hpp"),
            Line(),
            Value(
                "texture<fp_tex_%s, 1, cudaReadModeElementType>" %
                dtype_to_ctype(float_type), "in_vector_tex"),
        ])
        if with_scaling:
            cmod.append(
                Value(
                    "texture<fp_tex_%s, 1, cudaReadModeElementType>" %
                    dtype_to_ctype(float_type), "scaling_tex"), )

        par = self.plan.parallelism

        cmod.extend([
            Line(),
            Define("DIMENSIONS", discr.dimensions),
            Define("DOFS_PER_EL", given.dofs_per_el()),
            Define("PREIMAGE_DOFS_PER_EL", self.plan.preimage_dofs_per_el),
            Line(),
            Define("SEGMENT_DOF", "threadIdx.x"),
            Define("PAR_MB_NR", "threadIdx.y"),
            Line(),
            Define("MB_SEGMENT", "blockIdx.x"),
            Define("MACROBLOCK_NR", "blockIdx.y"),
            Line(),
            Define("DOFS_PER_SEGMENT", self.plan.segment_size),
            Define("SEGMENTS_PER_MB", self.plan.segments_per_microblock()),
            Define("ALIGNED_DOFS_PER_MB", given.microblock.aligned_floats),
            Define("ALIGNED_PREIMAGE_DOFS_PER_MB",
                   self.plan.aligned_preimage_dofs_per_microblock),
            Define("MB_EL_COUNT", given.microblock.elements),
            Line(),
            Define("PAR_MB_COUNT", par.parallel),
            Define("INLINE_MB_COUNT", par.inline),
            Define("SEQ_MB_COUNT", par.serial),
            Line(),
            Define("THREAD_NUM", "(SEGMENT_DOF+PAR_MB_NR*DOFS_PER_SEGMENT)"),
            Define("COALESCING_THREAD_COUNT",
                   "(PAR_MB_COUNT*DOFS_PER_SEGMENT)"),
            Line(),
            Define("MB_DOF_BASE", "(MB_SEGMENT*DOFS_PER_SEGMENT)"),
            Define("MB_DOF", "(MB_DOF_BASE+SEGMENT_DOF)"),
            Define(
                "GLOBAL_MB_NR_BASE",
                "(MACROBLOCK_NR*PAR_MB_COUNT*INLINE_MB_COUNT*SEQ_MB_COUNT)"),
            Define(
                "GLOBAL_MB_NR", "(GLOBAL_MB_NR_BASE"
                "+ (seq_mb_number*PAR_MB_COUNT + PAR_MB_NR)*INLINE_MB_COUNT)"),
            Define("GLOBAL_MB_DOF_BASE", "(GLOBAL_MB_NR*ALIGNED_DOFS_PER_MB)"),
            Define("GLOBAL_MB_PREIMG_DOF_BASE",
                   "(GLOBAL_MB_NR*ALIGNED_PREIMAGE_DOFS_PER_MB)"),
            Line(),
            Define("MATRIX_COLUMNS", self.plan.gpu_matrix_columns()),
            Define("MATRIX_SEGMENT_FLOATS",
                   self.plan.gpu_matrix_block_floats()),
            Define("MATRIX_SEGMENT_BYTES",
                   "(MATRIX_SEGMENT_FLOATS*%d)" % given.float_size()),
            Line(),
            CudaShared(
                ArrayOf(POD(float_type, "smem_matrix"),
                        "MATRIX_SEGMENT_FLOATS")),
            CudaShared(
                ArrayOf(
                    ArrayOf(
                        ArrayOf(POD(float_type, "dof_buffer"), "PAR_MB_COUNT"),
                        "INLINE_MB_COUNT"), "DOFS_PER_SEGMENT"), ),
            CudaShared(POD(numpy.uint16, "segment_start_el")),
            CudaShared(POD(numpy.uint16, "segment_stop_el")),
            CudaShared(POD(numpy.uint16, "segment_el_count")),
            Line(),
            ArrayInitializer(
                CudaConstant(
                    ArrayOf(POD(numpy.uint32, "segment_start_el_lookup"),
                            "SEGMENTS_PER_MB")),
                [(chk * self.plan.segment_size) // given.dofs_per_el()
                 for chk in range(self.plan.segments_per_microblock())]),
            ArrayInitializer(
                CudaConstant(
                    ArrayOf(POD(numpy.uint32, "segment_stop_el_lookup"),
                            "SEGMENTS_PER_MB")),
                [
                    min(given.microblock.elements,
                        (chk * self.plan.segment_size +
                         self.plan.segment_size - 1) // given.dofs_per_el() +
                        1)
                    for chk in range(self.plan.segments_per_microblock())
                ]),
        ])

        S = Statement
        f_body = Block()

        f_body.extend_log_block(
            "calculate this dof's element",
            [Initializer(POD(numpy.uint8, "mb_el"), "MB_DOF/DOFS_PER_EL")])

        if self.plan.use_prefetch_branch:
            f_body.extend_log_block("calculate segment responsibility data", [
                If(
                    "THREAD_NUM==0",
                    Block([
                        Assign("segment_start_el",
                               "segment_start_el_lookup[MB_SEGMENT]"),
                        Assign("segment_stop_el",
                               "segment_stop_el_lookup[MB_SEGMENT]"),
                        Assign("segment_el_count",
                               "segment_stop_el-segment_start_el"),
                    ])),
                S("__syncthreads()")
            ])

        from hedge.backends.cuda.tools import get_load_code
        f_body.extend(
            get_load_code(dest="smem_matrix",
                          base=(
                              "gmem_matrix + MB_SEGMENT*MATRIX_SEGMENT_BYTES"),
                          bytes="MATRIX_SEGMENT_BYTES",
                          descr="load matrix segment") +
            [S("__syncthreads()")])

        # ---------------------------------------------------------------------
        def get_batched_fetch_mat_mul_code(el_fetch_count):
            result = []
            dofs = range(self.plan.preimage_dofs_per_el)

            for load_segment_start in range(0, self.plan.preimage_dofs_per_el,
                                            self.plan.segment_size):
                result.extend([S("__syncthreads()")] + [
                    Assign(
                        "dof_buffer[PAR_MB_NR][%d][SEGMENT_DOF]" %
                        inl, "fp_tex1Dfetch(in_vector_tex, "
                        "GLOBAL_MB_PREIMG_DOF_BASE"
                        " + %d*ALIGNED_PREIMAGE_DOFS_PER_MB"
                        " + (segment_start_el)*PREIMAGE_DOFS_PER_EL + %d + SEGMENT_DOF)"
                        % (inl, load_segment_start))
                    for inl in range(par.inline)
                ] + [
                    S("__syncthreads()"),
                    Line(),
                ])

                for dof in dofs[load_segment_start:load_segment_start +
                                self.plan.segment_size]:
                    for inl in range(par.inline):
                        result.append(
                            S("result%d += "
                              "smem_matrix[SEGMENT_DOF*MATRIX_COLUMNS + %d]"
                              "*"
                              "dof_buffer[PAR_MB_NR][%d][%d]" %
                              (inl, dof, inl, dof - load_segment_start)))
                result.append(Line())
            return result

        from hedge.backends.cuda.tools import unroll

        def get_direct_tex_mat_mul_code():
            return (
                [POD(float_type, "fof%d" % inl) for inl in range(par.inline)] +
                [POD(float_type, "lm"), Line()] + unroll(
                    lambda j: [
                        Assign(
                            "fof%d" % inl,
                            "fp_tex1Dfetch(in_vector_tex, "
                            "GLOBAL_MB_PREIMG_DOF_BASE"
                            " + %(inl)d * ALIGNED_PREIMAGE_DOFS_PER_MB"
                            " + mb_el*PREIMAGE_DOFS_PER_EL+%(j)s)" % {
                                "j": j,
                                "inl": inl,
                                "row": "SEGMENT_DOF"
                            },
                        ) for inl in range(par.inline)
                    ] + [
                        Assign(
                            "lm",
                            "smem_matrix["
                            "%(row)s*MATRIX_COLUMNS + %(j)s]" % {
                                "j": j,
                                "row": "SEGMENT_DOF"
                            },
                        )
                    ] + [
                        S("result%(inl)d += fof%(inl)d*lm" % {"inl": inl})
                        for inl in range(par.inline)
                    ],
                    total_number=self.plan.preimage_dofs_per_el,
                    max_unroll=self.plan.max_unroll) + [Line()])

        def get_mat_mul_code(el_fetch_count):
            if el_fetch_count == 1:
                return get_batched_fetch_mat_mul_code(el_fetch_count)
            else:
                return get_direct_tex_mat_mul_code()

        def mat_mul_outer_loop(fetch_count):
            if with_scaling:
                inv_jac_multiplier = (
                    "fp_tex1Dfetch(scaling_tex,"
                    "(GLOBAL_MB_NR + %(inl)d)*MB_EL_COUNT + mb_el)")
            else:
                inv_jac_multiplier = "1"

            write_condition = "MB_DOF < DOFS_PER_EL*MB_EL_COUNT"
            if self.with_index_check:
                write_condition += " && GLOBAL_MB_NR < microblock_count"
            return For(
                "unsigned short seq_mb_number = 0",
                "seq_mb_number < SEQ_MB_COUNT", "++seq_mb_number",
                Block([
                    Initializer(POD(float_type, "result%d" % inl), 0)
                    for inl in range(par.inline)
                ] + [Line()] + get_mat_mul_code(fetch_count) + [
                    If(
                        write_condition,
                        Block([
                            Assign(
                                "out_vector[GLOBAL_MB_DOF_BASE"
                                " + %d*ALIGNED_DOFS_PER_MB"
                                " + MB_DOF]" % inl, "result%d * %s" %
                                (inl, (inv_jac_multiplier % {
                                    "inl": inl
                                }))) for inl in range(par.inline)
                        ]))
                ]))

        if self.plan.use_prefetch_branch:
            from cgen import make_multiple_ifs
            f_body.append(
                make_multiple_ifs([
                    ("segment_el_count == %d" % fetch_count,
                     mat_mul_outer_loop(fetch_count)) for fetch_count in range(
                         1,
                         self.plan.max_elements_touched_by_segment() + 1)
                ]))
        else:
            f_body.append(mat_mul_outer_loop(0))

        # finish off ----------------------------------------------------------
        cmod.append(FunctionBody(f_decl, f_body))

        if not for_benchmark and "cuda_dump_kernels" in discr.debug:
            from hedge.tools import open_unique_debug_file
            open_unique_debug_file(self.plan.debug_name,
                                   ".cu").write(str(cmod))

        mod = SourceModule(
            cmod,
            keep="cuda_keep_kernels" in discr.debug,
            #options=["--maxrregcount=12"]
        )

        func = mod.get_function("apply_el_local_mat_smem_mat")

        if self.plan.debug_name in discr.debug:
            print "%s: lmem=%d smem=%d regs=%d" % (
                self.plan.debug_name, func.local_size_bytes,
                func.shared_size_bytes, func.num_regs)

        in_vector_texref = mod.get_texref("in_vector_tex")
        texrefs = [in_vector_texref]

        if with_scaling:
            scaling_texref = mod.get_texref("scaling_tex")
            texrefs.append(scaling_texref)
        else:
            scaling_texref = None

        func.prepare("PPPI",
                     block=(self.plan.segment_size,
                            self.plan.parallelism.parallel, 1),
                     texrefs=texrefs)

        return func, in_vector_texref, scaling_texref