-}
-
-
-/* Function vect_get_new_vect_var.
-
- Returns a name for a new variable. The current naming scheme appends the
- prefix "vect_" or "vect_p" (depending on the value of VAR_KIND) to
- the name of vectorizer generated variables, and appends that to NAME if
- provided. */
-
-static tree
-vect_get_new_vect_var (tree type, enum vect_var_kind var_kind, const char *name)
-{
- const char *prefix;
- int prefix_len;
- tree new_vect_var;
-
- if (var_kind == vect_simple_var)
- prefix = "vect_";
- else
- prefix = "vect_p";
-
- prefix_len = strlen (prefix);
-
- if (name)
- new_vect_var = create_tmp_var (type, concat (prefix, name, NULL));
- else
- new_vect_var = create_tmp_var (type, prefix);
-
- return new_vect_var;
-}
-
-
-/* Function vect_create_index_for_vector_ref.
-
- Create (and return) an index variable, along with it's update chain in the
- loop. This variable will be used to access a memory location in a vector
- operation.
-
- Input:
- LOOP: The loop being vectorized.
- BSI: The block_stmt_iterator where STMT is. Any new stmts created by this
- function can be added here, or in the loop pre-header.
-
- Output:
- Return an index that will be used to index a vector array. It is expected
- that a pointer to the first vector will be used as the base address for the
- indexed reference.
-
- FORNOW: we are not trying to be efficient, just creating a new index each
- time from scratch. At this time all vector references could use the same
- index.
-
- TODO: create only one index to be used by all vector references. Record
- the index in the LOOP_VINFO the first time this procedure is called and
- return it on subsequent calls. The increment of this index must be placed
- just before the conditional expression that ends the single block loop. */
-
-static tree
-vect_create_index_for_vector_ref (struct loop *loop, block_stmt_iterator *bsi)
-{
- tree init, step;
- tree indx_before_incr, indx_after_incr;
-
- /* It is assumed that the base pointer used for vectorized access contains
- the address of the first vector. Therefore the index used for vectorized
- access must be initialized to zero and incremented by 1. */
-
- init = integer_zero_node;
- step = integer_one_node;
-
- /* Assuming that bsi_insert is used with BSI_NEW_STMT */
- create_iv (init, step, NULL_TREE, loop, bsi, false,
- &indx_before_incr, &indx_after_incr);
-
- return indx_before_incr;
-}
-
-
-/* Function vect_create_addr_base_for_vector_ref.
-
- Create an expression that computes the address of the first memory location
- that will be accessed for a data reference.
-
- Input:
- STMT: The statement containing the data reference.
- NEW_STMT_LIST: Must be initialized to NULL_TREE or a statement list.
- OFFSET: Optional. If supplied, it is be added to the initial address.
-
- Output:
- 1. Return an SSA_NAME whose value is the address of the memory location of
- the first vector of the data reference.
- 2. If new_stmt_list is not NULL_TREE after return then the caller must insert
- these statement(s) which define the returned SSA_NAME.
-
- FORNOW: We are only handling array accesses with step 1. */
-
-static tree
-vect_create_addr_base_for_vector_ref (tree stmt,
- tree *new_stmt_list,
- tree offset)
-{
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- struct loop *loop = STMT_VINFO_LOOP (stmt_info);
- struct data_reference *dr = STMT_VINFO_DATA_REF (stmt_info);
- tree data_ref_base = unshare_expr (STMT_VINFO_VECT_DR_BASE (stmt_info));
- tree base_name = unshare_expr (DR_BASE_NAME (dr));
- tree ref = DR_REF (dr);
- tree data_ref_base_type = TREE_TYPE (data_ref_base);
- tree scalar_type = TREE_TYPE (ref);
- tree scalar_ptr_type = build_pointer_type (scalar_type);
- tree access_fn;
- tree init_val, step, init_oval;
- bool ok;
- bool is_ptr_ref, is_array_ref, is_addr_expr;
- tree array_base;
- tree vec_stmt;
- tree new_temp;
- tree array_ref;
- tree addr_base, addr_expr;
- tree dest, new_stmt;
-
- /* Only the access function of the last index is relevant (i_n in
- a[i_1][i_2]...[i_n]), the others correspond to loop invariants. */
- access_fn = DR_ACCESS_FN (dr, 0);
- ok = vect_is_simple_iv_evolution (loop->num, access_fn, &init_oval, &step,
- true);
- if (!ok)
- init_oval = integer_zero_node;
-
- is_ptr_ref = TREE_CODE (data_ref_base_type) == POINTER_TYPE
- && TREE_CODE (data_ref_base) == SSA_NAME;
- is_array_ref = TREE_CODE (data_ref_base_type) == ARRAY_TYPE;
- is_addr_expr = TREE_CODE (data_ref_base) == ADDR_EXPR
- || TREE_CODE (data_ref_base) == PLUS_EXPR
- || TREE_CODE (data_ref_base) == MINUS_EXPR;
- gcc_assert (is_ptr_ref || is_array_ref || is_addr_expr);
-
- /** Create: &(base[init_val])
-
- if data_ref_base is an ARRAY_TYPE:
- base = data_ref_base
-
- if data_ref_base is the SSA_NAME of a POINTER_TYPE:
- base = *((scalar_array *) data_ref_base)
- **/
-
- if (is_array_ref)
- array_base = data_ref_base;
- else /* is_ptr_ref or is_addr_expr */
- {
- /* array_ptr = (scalar_array_ptr_type *) data_ref_base; */
- tree scalar_array_type = build_array_type (scalar_type, 0);
- tree scalar_array_ptr_type = build_pointer_type (scalar_array_type);
- tree array_ptr = create_tmp_var (scalar_array_ptr_type, "array_ptr");
- add_referenced_tmp_var (array_ptr);
-
- dest = create_tmp_var (TREE_TYPE (data_ref_base), "dataref");
- add_referenced_tmp_var (dest);
- data_ref_base =
- force_gimple_operand (data_ref_base, &new_stmt, false, dest);
- append_to_statement_list_force (new_stmt, new_stmt_list);
-
- vec_stmt = fold_convert (scalar_array_ptr_type, data_ref_base);
- vec_stmt = build2 (MODIFY_EXPR, void_type_node, array_ptr, vec_stmt);
- new_temp = make_ssa_name (array_ptr, vec_stmt);
- TREE_OPERAND (vec_stmt, 0) = new_temp;
- append_to_statement_list_force (vec_stmt, new_stmt_list);
-
- /* (*array_ptr) */
- array_base = build_fold_indirect_ref (new_temp);
- }
-
- dest = create_tmp_var (TREE_TYPE (init_oval), "newinit");
- add_referenced_tmp_var (dest);
- init_val = force_gimple_operand (init_oval, &new_stmt, false, dest);
- append_to_statement_list_force (new_stmt, new_stmt_list);
-
- if (offset)
- {
- tree tmp = create_tmp_var (TREE_TYPE (init_val), "offset");
- add_referenced_tmp_var (tmp);
- vec_stmt = build2 (PLUS_EXPR, TREE_TYPE (init_val), init_val, offset);
- vec_stmt = build2 (MODIFY_EXPR, TREE_TYPE (init_val), tmp, vec_stmt);
- init_val = make_ssa_name (tmp, vec_stmt);
- TREE_OPERAND (vec_stmt, 0) = init_val;
- append_to_statement_list_force (vec_stmt, new_stmt_list);
- }
-
- array_ref = build4 (ARRAY_REF, scalar_type, array_base, init_val,
- NULL_TREE, NULL_TREE);
- addr_base = build_fold_addr_expr (array_ref);
-
- /* addr_expr = addr_base */
- addr_expr = vect_get_new_vect_var (scalar_ptr_type, vect_pointer_var,
- get_name (base_name));
- add_referenced_tmp_var (addr_expr);
- vec_stmt = build2 (MODIFY_EXPR, void_type_node, addr_expr, addr_base);
- new_temp = make_ssa_name (addr_expr, vec_stmt);
- TREE_OPERAND (vec_stmt, 0) = new_temp;
- append_to_statement_list_force (vec_stmt, new_stmt_list);
-
- return new_temp;
-}
-
-
-/* Function get_vectype_for_scalar_type.
-
- Returns the vector type corresponding to SCALAR_TYPE as supported
- by the target. */
-
-static tree
-get_vectype_for_scalar_type (tree scalar_type)
-{
- enum machine_mode inner_mode = TYPE_MODE (scalar_type);
- int nbytes = GET_MODE_SIZE (inner_mode);
- int nunits;
- tree vectype;
-
- if (nbytes == 0)
- return NULL_TREE;
-
- /* FORNOW: Only a single vector size per target (UNITS_PER_SIMD_WORD)
- is expected. */
- nunits = UNITS_PER_SIMD_WORD / nbytes;
-
- vectype = build_vector_type (scalar_type, nunits);
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "get vectype with %d units of type ", nunits);
- print_generic_expr (dump_file, scalar_type, TDF_SLIM);
- }
-
- if (!vectype)
- return NULL_TREE;
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "vectype: ");
- print_generic_expr (dump_file, vectype, TDF_SLIM);
- }
-
- if (!VECTOR_MODE_P (TYPE_MODE (vectype)))
- {
- /* TODO: tree-complex.c sometimes can parallelize operations
- on generic vectors. We can vectorize the loop in that case,
- but then we should re-run the lowering pass. */
- if (vect_debug_details (NULL))
- fprintf (dump_file, "mode not supported by target.");
- return NULL_TREE;
- }
-
- return vectype;
-}
-
-
-/* Function vect_align_data_ref.
-
- Handle mislignment of a memory accesses.
-
- FORNOW: Can't handle misaligned accesses.
- Make sure that the dataref is aligned. */
-
-static void
-vect_align_data_ref (tree stmt)
-{
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- struct data_reference *dr = STMT_VINFO_DATA_REF (stmt_info);
-
- /* FORNOW: can't handle misaligned accesses;
- all accesses expected to be aligned. */
- gcc_assert (aligned_access_p (dr));
-}
-
-
-/* Function vect_create_data_ref_ptr.
-
- Create a memory reference expression for vector access, to be used in a
- vector load/store stmt. The reference is based on a new pointer to vector
- type (vp).
-
- Input:
- 1. STMT: a stmt that references memory. Expected to be of the form
- MODIFY_EXPR <name, data-ref> or MODIFY_EXPR <data-ref, name>.
- 2. BSI: block_stmt_iterator where new stmts can be added.
- 3. OFFSET (optional): an offset to be added to the initial address accessed
- by the data-ref in STMT.
- 4. ONLY_INIT: indicate if vp is to be updated in the loop, or remain
- pointing to the initial address.
-
- Output:
- 1. Declare a new ptr to vector_type, and have it point to the base of the
- data reference (initial addressed accessed by the data reference).
- For example, for vector of type V8HI, the following code is generated:
-
- v8hi *vp;
- vp = (v8hi *)initial_address;
-
- if OFFSET is not supplied:
- initial_address = &a[init];
- if OFFSET is supplied:
- initial_address = &a[init + OFFSET];
-
- Return the initial_address in INITIAL_ADDRESS.
-
- 2. Create a data-reference in the loop based on the new vector pointer vp,
- and using a new index variable 'idx' as follows:
-
- vp' = vp + update
-
- where if ONLY_INIT is true:
- update = zero
- and otherwise
- update = idx + vector_type_size
-
- Return the pointer vp'.
-
-
- FORNOW: handle only aligned and consecutive accesses. */
-
-static tree
-vect_create_data_ref_ptr (tree stmt, block_stmt_iterator *bsi, tree offset,
- tree *initial_address, bool only_init)
-{
- tree base_name;
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- struct data_reference *dr = STMT_VINFO_DATA_REF (stmt_info);
- struct loop *loop = STMT_VINFO_LOOP (stmt_info);
- tree vectype = STMT_VINFO_VECTYPE (stmt_info);
- tree vect_ptr_type;
- tree vect_ptr;
- tree tag;
- v_may_def_optype v_may_defs = STMT_V_MAY_DEF_OPS (stmt);
- v_must_def_optype v_must_defs = STMT_V_MUST_DEF_OPS (stmt);
- vuse_optype vuses = STMT_VUSE_OPS (stmt);
- int nvuses, nv_may_defs, nv_must_defs;
- int i;
- tree new_temp;
- tree vec_stmt;
- tree new_stmt_list = NULL_TREE;
- tree idx;
- edge pe = loop_preheader_edge (loop);
- basic_block new_bb;
- tree vect_ptr_init;
- tree vectype_size;
- tree ptr_update;
- tree data_ref_ptr;
- tree type, tmp, size;
-
- base_name = unshare_expr (DR_BASE_NAME (dr));
- if (vect_debug_details (NULL))
- {
- tree data_ref_base = base_name;
- fprintf (dump_file, "create array_ref of type: ");
- print_generic_expr (dump_file, vectype, TDF_SLIM);
- if (TREE_CODE (data_ref_base) == VAR_DECL)
- fprintf (dump_file, "vectorizing a one dimensional array ref: ");
- else if (TREE_CODE (data_ref_base) == ARRAY_REF)
- fprintf (dump_file, "vectorizing a multidimensional array ref: ");
- else if (TREE_CODE (data_ref_base) == COMPONENT_REF)
- fprintf (dump_file, "vectorizing a record based array ref: ");
- else if (TREE_CODE (data_ref_base) == SSA_NAME)
- fprintf (dump_file, "vectorizing a pointer ref: ");
- print_generic_expr (dump_file, base_name, TDF_SLIM);
- }
-
- /** (1) Create the new vector-pointer variable: **/
-
- vect_ptr_type = build_pointer_type (vectype);
- vect_ptr = vect_get_new_vect_var (vect_ptr_type, vect_pointer_var,
- get_name (base_name));
- add_referenced_tmp_var (vect_ptr);
-
-
- /** (2) Handle aliasing information of the new vector-pointer: **/
-
- tag = STMT_VINFO_MEMTAG (stmt_info);
- gcc_assert (tag);
- get_var_ann (vect_ptr)->type_mem_tag = tag;
-
- /* Mark for renaming all aliased variables
- (i.e, the may-aliases of the type-mem-tag). */
- nvuses = NUM_VUSES (vuses);
- nv_may_defs = NUM_V_MAY_DEFS (v_may_defs);
- nv_must_defs = NUM_V_MUST_DEFS (v_must_defs);
- for (i = 0; i < nvuses; i++)
- {
- tree use = VUSE_OP (vuses, i);
- if (TREE_CODE (use) == SSA_NAME)
- bitmap_set_bit (vars_to_rename, var_ann (SSA_NAME_VAR (use))->uid);
- }
- for (i = 0; i < nv_may_defs; i++)
- {
- tree def = V_MAY_DEF_RESULT (v_may_defs, i);
- if (TREE_CODE (def) == SSA_NAME)
- bitmap_set_bit (vars_to_rename, var_ann (SSA_NAME_VAR (def))->uid);
- }
- for (i = 0; i < nv_must_defs; i++)
- {
- tree def = V_MUST_DEF_RESULT (v_must_defs, i);
- if (TREE_CODE (def) == SSA_NAME)
- bitmap_set_bit (vars_to_rename, var_ann (SSA_NAME_VAR (def))->uid);
- }
-
-
- /** (3) Calculate the initial address the vector-pointer, and set
- the vector-pointer to point to it before the loop: **/
-
- /* Create: (&(base[init_val+offset]) in the loop preheader. */
- new_temp = vect_create_addr_base_for_vector_ref (stmt, &new_stmt_list,
- offset);
- pe = loop_preheader_edge (loop);
- new_bb = bsi_insert_on_edge_immediate (pe, new_stmt_list);
- gcc_assert (!new_bb);
- *initial_address = new_temp;
-
- /* Create: p = (vectype *) initial_base */
- vec_stmt = fold_convert (vect_ptr_type, new_temp);
- vec_stmt = build2 (MODIFY_EXPR, void_type_node, vect_ptr, vec_stmt);
- new_temp = make_ssa_name (vect_ptr, vec_stmt);
- TREE_OPERAND (vec_stmt, 0) = new_temp;
- new_bb = bsi_insert_on_edge_immediate (pe, vec_stmt);
- gcc_assert (!new_bb);
- vect_ptr_init = TREE_OPERAND (vec_stmt, 0);
-
-
- /** (4) Handle the updating of the vector-pointer inside the loop: **/
-
- if (only_init) /* No update in loop is required. */
- return vect_ptr_init;
-
- idx = vect_create_index_for_vector_ref (loop, bsi);
-
- /* Create: update = idx * vectype_size */
- tmp = create_tmp_var (integer_type_node, "update");
- add_referenced_tmp_var (tmp);
- size = TYPE_SIZE (vect_ptr_type);
- type = lang_hooks.types.type_for_size (tree_low_cst (size, 1), 1);
- ptr_update = create_tmp_var (type, "update");
- add_referenced_tmp_var (ptr_update);
- vectype_size = build_int_cst (integer_type_node,
- GET_MODE_SIZE (TYPE_MODE (vectype)));
- vec_stmt = build2 (MULT_EXPR, integer_type_node, idx, vectype_size);
- vec_stmt = build2 (MODIFY_EXPR, void_type_node, tmp, vec_stmt);
- new_temp = make_ssa_name (tmp, vec_stmt);
- TREE_OPERAND (vec_stmt, 0) = new_temp;
- bsi_insert_before (bsi, vec_stmt, BSI_SAME_STMT);
- vec_stmt = fold_convert (type, new_temp);
- vec_stmt = build2 (MODIFY_EXPR, void_type_node, ptr_update, vec_stmt);
- new_temp = make_ssa_name (ptr_update, vec_stmt);
- TREE_OPERAND (vec_stmt, 0) = new_temp;
- bsi_insert_before (bsi, vec_stmt, BSI_SAME_STMT);
-
- /* Create: data_ref_ptr = vect_ptr_init + update */
- vec_stmt = build2 (PLUS_EXPR, vect_ptr_type, vect_ptr_init, new_temp);
- vec_stmt = build2 (MODIFY_EXPR, void_type_node, vect_ptr, vec_stmt);
- new_temp = make_ssa_name (vect_ptr, vec_stmt);
- TREE_OPERAND (vec_stmt, 0) = new_temp;
- bsi_insert_before (bsi, vec_stmt, BSI_SAME_STMT);
- data_ref_ptr = TREE_OPERAND (vec_stmt, 0);
-
- return data_ref_ptr;
-}
-
-
-/* Function vect_create_destination_var.
-
- Create a new temporary of type VECTYPE. */
-
-static tree
-vect_create_destination_var (tree scalar_dest, tree vectype)
-{
- tree vec_dest;
- const char *new_name;
-
- gcc_assert (TREE_CODE (scalar_dest) == SSA_NAME);
-
- new_name = get_name (scalar_dest);
- if (!new_name)
- new_name = "var_";
- vec_dest = vect_get_new_vect_var (vectype, vect_simple_var, new_name);
- add_referenced_tmp_var (vec_dest);
-
- return vec_dest;
-}
-
-
-/* Function vect_init_vector.
-
- Insert a new stmt (INIT_STMT) that initializes a new vector variable with
- the vector elements of VECTOR_VAR. Return the DEF of INIT_STMT. It will be
- used in the vectorization of STMT. */
-
-static tree
-vect_init_vector (tree stmt, tree vector_var)
-{
- stmt_vec_info stmt_vinfo = vinfo_for_stmt (stmt);
- struct loop *loop = STMT_VINFO_LOOP (stmt_vinfo);
- tree new_var;
- tree init_stmt;
- tree vectype = STMT_VINFO_VECTYPE (stmt_vinfo);
- tree vec_oprnd;
- edge pe;
- tree new_temp;
- basic_block new_bb;
-
- new_var = vect_get_new_vect_var (vectype, vect_simple_var, "cst_");
- add_referenced_tmp_var (new_var);
-
- init_stmt = build2 (MODIFY_EXPR, vectype, new_var, vector_var);
- new_temp = make_ssa_name (new_var, init_stmt);
- TREE_OPERAND (init_stmt, 0) = new_temp;
-
- pe = loop_preheader_edge (loop);
- new_bb = bsi_insert_on_edge_immediate (pe, init_stmt);
- gcc_assert (!new_bb);
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "created new init_stmt: ");
- print_generic_expr (dump_file, init_stmt, TDF_SLIM);
- }
-
- vec_oprnd = TREE_OPERAND (init_stmt, 0);
- return vec_oprnd;
-}
-
-
-/* Function vect_get_vec_def_for_operand.
-
- OP is an operand in STMT. This function returns a (vector) def that will be
- used in the vectorized stmt for STMT.
-
- In the case that OP is an SSA_NAME which is defined in the loop, then
- STMT_VINFO_VEC_STMT of the defining stmt holds the relevant def.
-
- In case OP is an invariant or constant, a new stmt that creates a vector def
- needs to be introduced. */
-
-static tree
-vect_get_vec_def_for_operand (tree op, tree stmt)
-{
- tree vec_oprnd;
- tree vec_stmt;
- tree def_stmt;
- stmt_vec_info def_stmt_info = NULL;
- stmt_vec_info stmt_vinfo = vinfo_for_stmt (stmt);
- tree vectype = STMT_VINFO_VECTYPE (stmt_vinfo);
- int nunits = GET_MODE_NUNITS (TYPE_MODE (vectype));
- struct loop *loop = STMT_VINFO_LOOP (stmt_vinfo);
- basic_block bb;
- tree vec_inv;
- tree t = NULL_TREE;
- tree def;
- int i;
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "vect_get_vec_def_for_operand: ");
- print_generic_expr (dump_file, op, TDF_SLIM);
- }
-
- /** ===> Case 1: operand is a constant. **/
-
- if (TREE_CODE (op) == INTEGER_CST || TREE_CODE (op) == REAL_CST)
- {
- /* Create 'vect_cst_ = {cst,cst,...,cst}' */
-
- tree vec_cst;
-
- /* Build a tree with vector elements. */
- if (vect_debug_details (NULL))
- fprintf (dump_file, "Create vector_cst. nunits = %d", nunits);
-
- for (i = nunits - 1; i >= 0; --i)
- {
- t = tree_cons (NULL_TREE, op, t);
- }
- vec_cst = build_vector (vectype, t);
- return vect_init_vector (stmt, vec_cst);
- }
-
- gcc_assert (TREE_CODE (op) == SSA_NAME);
-
- /** ===> Case 2: operand is an SSA_NAME - find the stmt that defines it. **/
-
- def_stmt = SSA_NAME_DEF_STMT (op);
- def_stmt_info = vinfo_for_stmt (def_stmt);
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "vect_get_vec_def_for_operand: def_stmt: ");
- print_generic_expr (dump_file, def_stmt, TDF_SLIM);
- }
-
-
- /** ==> Case 2.1: operand is defined inside the loop. **/
-
- if (def_stmt_info)
- {
- /* Get the def from the vectorized stmt. */
-
- vec_stmt = STMT_VINFO_VEC_STMT (def_stmt_info);
- gcc_assert (vec_stmt);
- vec_oprnd = TREE_OPERAND (vec_stmt, 0);
- return vec_oprnd;
- }
-
-
- /** ==> Case 2.2: operand is defined by the loop-header phi-node -
- it is a reduction/induction. **/
-
- bb = bb_for_stmt (def_stmt);
- if (TREE_CODE (def_stmt) == PHI_NODE && flow_bb_inside_loop_p (loop, bb))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "reduction/induction - unsupported.");
- internal_error ("no support for reduction/induction"); /* FORNOW */
- }
-
-
- /** ==> Case 2.3: operand is defined outside the loop -
- it is a loop invariant. */
-
- switch (TREE_CODE (def_stmt))
- {
- case PHI_NODE:
- def = PHI_RESULT (def_stmt);
- break;
- case MODIFY_EXPR:
- def = TREE_OPERAND (def_stmt, 0);
- break;
- case NOP_EXPR:
- def = TREE_OPERAND (def_stmt, 0);
- gcc_assert (IS_EMPTY_STMT (def_stmt));
- def = op;
- break;
- default:
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "unsupported defining stmt: ");
- print_generic_expr (dump_file, def_stmt, TDF_SLIM);
- }
- internal_error ("unsupported defining stmt");
- }
-
- /* Build a tree with vector elements. Create 'vec_inv = {inv,inv,..,inv}' */
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "Create vector_inv.");
-
- for (i = nunits - 1; i >= 0; --i)
- {
- t = tree_cons (NULL_TREE, def, t);
- }
-
- vec_inv = build_constructor (vectype, t);
- return vect_init_vector (stmt, vec_inv);
-}
-
-
-/* Function vect_finish_stmt_generation.
-
- Insert a new stmt. */
-
-static void
-vect_finish_stmt_generation (tree stmt, tree vec_stmt, block_stmt_iterator *bsi)
-{
- bsi_insert_before (bsi, vec_stmt, BSI_SAME_STMT);
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "add new stmt: ");
- print_generic_expr (dump_file, vec_stmt, TDF_SLIM);
- }
-
- /* Make sure bsi points to the stmt that is being vectorized. */
-
- /* Assumption: any stmts created for the vectorization of stmt S were
- inserted before S. BSI is expected to point to S or some new stmt before S.
- */
-
- while (stmt != bsi_stmt (*bsi) && !bsi_end_p (*bsi))
- bsi_next (bsi);
- gcc_assert (stmt == bsi_stmt (*bsi));
-}
-
-
-/* Function vectorizable_assignment.
-
- Check if STMT performs an assignment (copy) that can be vectorized.
- If VEC_STMT is also passed, vectorize the STMT: create a vectorized
- stmt to replace it, put it in VEC_STMT, and insert it at BSI.
- Return FALSE if not a vectorizable STMT, TRUE otherwise. */
-
-static bool
-vectorizable_assignment (tree stmt, block_stmt_iterator *bsi, tree *vec_stmt)
-{
- tree vec_dest;
- tree scalar_dest;
- tree op;
- tree vec_oprnd;
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- tree vectype = STMT_VINFO_VECTYPE (stmt_info);
- struct loop *loop = STMT_VINFO_LOOP (stmt_info);
- tree new_temp;
-
- /* Is vectorizable assignment? */
-
- if (TREE_CODE (stmt) != MODIFY_EXPR)
- return false;
-
- scalar_dest = TREE_OPERAND (stmt, 0);
- if (TREE_CODE (scalar_dest) != SSA_NAME)
- return false;
-
- op = TREE_OPERAND (stmt, 1);
- if (!vect_is_simple_use (op, loop, NULL))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "use not simple.");
- return false;
- }
-
- if (!vec_stmt) /* transformation not required. */
- {
- STMT_VINFO_TYPE (stmt_info) = assignment_vec_info_type;
- return true;
- }
-
- /** Trasform. **/
- if (vect_debug_details (NULL))
- fprintf (dump_file, "transform assignment.");
-
- /* Handle def. */
- vec_dest = vect_create_destination_var (scalar_dest, vectype);
-
- /* Handle use. */
- op = TREE_OPERAND (stmt, 1);
- vec_oprnd = vect_get_vec_def_for_operand (op, stmt);
-
- /* Arguments are ready. create the new vector stmt. */
- *vec_stmt = build2 (MODIFY_EXPR, vectype, vec_dest, vec_oprnd);
- new_temp = make_ssa_name (vec_dest, *vec_stmt);
- TREE_OPERAND (*vec_stmt, 0) = new_temp;
- vect_finish_stmt_generation (stmt, *vec_stmt, bsi);
-
- return true;
-}
-
-
-/* Function vectorizable_operation.
-
- Check if STMT performs a binary or unary operation that can be vectorized.
- If VEC_STMT is also passed, vectorize the STMT: create a vectorized
- stmt to replace it, put it in VEC_STMT, and insert it at BSI.
- Return FALSE if not a vectorizable STMT, TRUE otherwise. */
-
-static bool
-vectorizable_operation (tree stmt, block_stmt_iterator *bsi, tree *vec_stmt)
-{
- tree vec_dest;
- tree scalar_dest;
- tree operation;
- tree op0, op1 = NULL;
- tree vec_oprnd0, vec_oprnd1=NULL;
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- tree vectype = STMT_VINFO_VECTYPE (stmt_info);
- struct loop *loop = STMT_VINFO_LOOP (stmt_info);
- int i;
- enum tree_code code;
- enum machine_mode vec_mode;
- tree new_temp;
- int op_type;
- tree op;
- optab optab;
-
- /* Is STMT a vectorizable binary/unary operation? */
- if (TREE_CODE (stmt) != MODIFY_EXPR)
- return false;
-
- if (TREE_CODE (TREE_OPERAND (stmt, 0)) != SSA_NAME)
- return false;
-
- operation = TREE_OPERAND (stmt, 1);
- code = TREE_CODE (operation);
- optab = optab_for_tree_code (code, vectype);
-
- /* Support only unary or binary operations. */
- op_type = TREE_CODE_LENGTH (code);
- if (op_type != unary_op && op_type != binary_op)
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "num. args = %d (not unary/binary op).", op_type);
- return false;
- }
-
- for (i = 0; i < op_type; i++)
- {
- op = TREE_OPERAND (operation, i);
- if (!vect_is_simple_use (op, loop, NULL))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "use not simple.");
- return false;
- }
- }
-
- /* Supportable by target? */
- if (!optab)
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "no optab.");
- return false;
- }
- vec_mode = TYPE_MODE (vectype);
- if (optab->handlers[(int) vec_mode].insn_code == CODE_FOR_nothing)
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "op not supported by target.");
- return false;
- }
-
- if (!vec_stmt) /* transformation not required. */
- {
- STMT_VINFO_TYPE (stmt_info) = op_vec_info_type;
- return true;
- }
-
- /** Transform. **/
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "transform binary/unary operation.");
-
- /* Handle def. */
- scalar_dest = TREE_OPERAND (stmt, 0);
- vec_dest = vect_create_destination_var (scalar_dest, vectype);
-
- /* Handle uses. */
- op0 = TREE_OPERAND (operation, 0);
- vec_oprnd0 = vect_get_vec_def_for_operand (op0, stmt);
-
- if (op_type == binary_op)
- {
- op1 = TREE_OPERAND (operation, 1);
- vec_oprnd1 = vect_get_vec_def_for_operand (op1, stmt);
- }
-
- /* Arguments are ready. create the new vector stmt. */
-
- if (op_type == binary_op)
- *vec_stmt = build2 (MODIFY_EXPR, vectype, vec_dest,
- build2 (code, vectype, vec_oprnd0, vec_oprnd1));
- else
- *vec_stmt = build2 (MODIFY_EXPR, vectype, vec_dest,
- build1 (code, vectype, vec_oprnd0));
- new_temp = make_ssa_name (vec_dest, *vec_stmt);
- TREE_OPERAND (*vec_stmt, 0) = new_temp;
- vect_finish_stmt_generation (stmt, *vec_stmt, bsi);
-
- return true;
-}
-
-
-/* Function vectorizable_store.
-
- Check if STMT defines a non scalar data-ref (array/pointer/structure) that
- can be vectorized.
- If VEC_STMT is also passed, vectorize the STMT: create a vectorized
- stmt to replace it, put it in VEC_STMT, and insert it at BSI.
- Return FALSE if not a vectorizable STMT, TRUE otherwise. */
-
-static bool
-vectorizable_store (tree stmt, block_stmt_iterator *bsi, tree *vec_stmt)
-{
- tree scalar_dest;
- tree data_ref;
- tree op;
- tree vec_oprnd1;
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- struct data_reference *dr = STMT_VINFO_DATA_REF (stmt_info);
- tree vectype = STMT_VINFO_VECTYPE (stmt_info);
- struct loop *loop = STMT_VINFO_LOOP (stmt_info);
- enum machine_mode vec_mode;
- tree dummy;
- enum dr_alignment_support alignment_support_cheme;
-
- /* Is vectorizable store? */
-
- if (TREE_CODE (stmt) != MODIFY_EXPR)
- return false;
-
- scalar_dest = TREE_OPERAND (stmt, 0);
- if (TREE_CODE (scalar_dest) != ARRAY_REF
- && TREE_CODE (scalar_dest) != INDIRECT_REF)
- return false;
-
- op = TREE_OPERAND (stmt, 1);
- if (!vect_is_simple_use (op, loop, NULL))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "use not simple.");
- return false;
- }
-
- vec_mode = TYPE_MODE (vectype);
- /* FORNOW. In some cases can vectorize even if data-type not supported
- (e.g. - array initialization with 0). */
- if (mov_optab->handlers[(int)vec_mode].insn_code == CODE_FOR_nothing)
- return false;
-
- if (!STMT_VINFO_DATA_REF (stmt_info))
- return false;
-
-
- if (!vec_stmt) /* transformation not required. */
- {
- STMT_VINFO_TYPE (stmt_info) = store_vec_info_type;
- return true;
- }
-
- /** Trasform. **/
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "transform store");
-
- alignment_support_cheme = vect_supportable_dr_alignment (dr);
- gcc_assert (alignment_support_cheme);
- gcc_assert (alignment_support_cheme = dr_aligned); /* FORNOW */
-
- /* Handle use - get the vectorized def from the defining stmt. */
- vec_oprnd1 = vect_get_vec_def_for_operand (op, stmt);
-
- /* Handle def. */
- /* FORNOW: make sure the data reference is aligned. */
- vect_align_data_ref (stmt);
- data_ref = vect_create_data_ref_ptr (stmt, bsi, NULL_TREE, &dummy, false);
- data_ref = build_fold_indirect_ref (data_ref);
-
- /* Arguments are ready. create the new vector stmt. */
- *vec_stmt = build2 (MODIFY_EXPR, vectype, data_ref, vec_oprnd1);
- vect_finish_stmt_generation (stmt, *vec_stmt, bsi);
-
- return true;
-}
-
-
-/* vectorizable_load.
-
- Check if STMT reads a non scalar data-ref (array/pointer/structure) that
- can be vectorized.
- If VEC_STMT is also passed, vectorize the STMT: create a vectorized
- stmt to replace it, put it in VEC_STMT, and insert it at BSI.
- Return FALSE if not a vectorizable STMT, TRUE otherwise. */
-
-static bool
-vectorizable_load (tree stmt, block_stmt_iterator *bsi, tree *vec_stmt)
-{
- tree scalar_dest;
- tree vec_dest = NULL;
- tree data_ref = NULL;
- tree op;
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- struct data_reference *dr = STMT_VINFO_DATA_REF (stmt_info);
- tree vectype = STMT_VINFO_VECTYPE (stmt_info);
- tree new_temp;
- int mode;
- tree init_addr;
- tree new_stmt;
- tree dummy;
- basic_block new_bb;
- struct loop *loop = STMT_VINFO_LOOP (stmt_info);
- edge pe = loop_preheader_edge (loop);
- enum dr_alignment_support alignment_support_cheme;
-
- /* Is vectorizable load? */
-
- if (TREE_CODE (stmt) != MODIFY_EXPR)
- return false;
-
- scalar_dest = TREE_OPERAND (stmt, 0);
- if (TREE_CODE (scalar_dest) != SSA_NAME)
- return false;
-
- op = TREE_OPERAND (stmt, 1);
- if (TREE_CODE (op) != ARRAY_REF && TREE_CODE (op) != INDIRECT_REF)
- return false;
-
- if (!STMT_VINFO_DATA_REF (stmt_info))
- return false;
-
- mode = (int) TYPE_MODE (vectype);
-
- /* FORNOW. In some cases can vectorize even if data-type not supported
- (e.g. - data copies). */
- if (mov_optab->handlers[mode].insn_code == CODE_FOR_nothing)
- {
- if (vect_debug_details (loop))
- fprintf (dump_file, "Aligned load, but unsupported type.");
- return false;
- }
-
- if (!vec_stmt) /* transformation not required. */
- {
- STMT_VINFO_TYPE (stmt_info) = load_vec_info_type;
- return true;
- }
-
- /** Trasform. **/
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "transform load.");
-
- alignment_support_cheme = vect_supportable_dr_alignment (dr);
- gcc_assert (alignment_support_cheme);
-
- if (alignment_support_cheme == dr_aligned
- || alignment_support_cheme == dr_unaligned_supported)
- {
- /* Create:
- p = initial_addr;
- indx = 0;
- loop {
- vec_dest = *(p);
- indx = indx + 1;
- }
- */
-
- vec_dest = vect_create_destination_var (scalar_dest, vectype);
- data_ref = vect_create_data_ref_ptr (stmt, bsi, NULL_TREE, &dummy, false);
- if (aligned_access_p (dr))
- data_ref = build_fold_indirect_ref (data_ref);
- else
- {
- int mis = DR_MISALIGNMENT (dr);
- tree tmis = (mis == -1 ?
- integer_zero_node :
- build_int_cst (integer_type_node, mis));
- tmis = int_const_binop (MULT_EXPR, tmis,
- build_int_cst (integer_type_node, BITS_PER_UNIT), 1);
- data_ref = build2 (MISALIGNED_INDIRECT_REF, vectype, data_ref, tmis);
- }
- new_stmt = build2 (MODIFY_EXPR, vectype, vec_dest, data_ref);
- new_temp = make_ssa_name (vec_dest, new_stmt);
- TREE_OPERAND (new_stmt, 0) = new_temp;
- vect_finish_stmt_generation (stmt, new_stmt, bsi);
- }
- else if (alignment_support_cheme == dr_unaligned_software_pipeline)
- {
- /* Create:
- p1 = initial_addr;
- msq_init = *(floor(p1))
- p2 = initial_addr + VS - 1;
- magic = have_builtin ? builtin_result : initial_address;
- indx = 0;
- loop {
- p2' = p2 + indx * vectype_size
- lsq = *(floor(p2'))
- vec_dest = realign_load (msq, lsq, magic)
- indx = indx + 1;
- msq = lsq;
- }
- */
-
- tree offset;
- tree magic;
- tree phi_stmt;
- tree msq_init;
- tree msq, lsq;
- tree dataref_ptr;
- tree params;
-
- /* <1> Create msq_init = *(floor(p1)) in the loop preheader */
- vec_dest = vect_create_destination_var (scalar_dest, vectype);
- data_ref = vect_create_data_ref_ptr (stmt, bsi, NULL_TREE,
- &init_addr, true);
- data_ref = build1 (ALIGN_INDIRECT_REF, vectype, data_ref);
- new_stmt = build2 (MODIFY_EXPR, vectype, vec_dest, data_ref);
- new_temp = make_ssa_name (vec_dest, new_stmt);
- TREE_OPERAND (new_stmt, 0) = new_temp;
- new_bb = bsi_insert_on_edge_immediate (pe, new_stmt);
- gcc_assert (!new_bb);
- msq_init = TREE_OPERAND (new_stmt, 0);
-
-
- /* <2> Create lsq = *(floor(p2')) in the loop */
- offset = build_int_cst (integer_type_node,
- GET_MODE_NUNITS (TYPE_MODE (vectype)));
- offset = int_const_binop (MINUS_EXPR, offset, integer_one_node, 1);
- vec_dest = vect_create_destination_var (scalar_dest, vectype);
- dataref_ptr = vect_create_data_ref_ptr (stmt, bsi, offset, &dummy, false);
- data_ref = build1 (ALIGN_INDIRECT_REF, vectype, dataref_ptr);
- new_stmt = build2 (MODIFY_EXPR, vectype, vec_dest, data_ref);
- new_temp = make_ssa_name (vec_dest, new_stmt);
- TREE_OPERAND (new_stmt, 0) = new_temp;
- vect_finish_stmt_generation (stmt, new_stmt, bsi);
- lsq = TREE_OPERAND (new_stmt, 0);
-
-
- /* <3> */
- if (targetm.vectorize.builtin_mask_for_load)
- {
- /* Create permutation mask, if required, in loop preheader. */
- tree builtin_decl;
- params = build_tree_list (NULL_TREE, init_addr);
- vec_dest = vect_create_destination_var (scalar_dest, vectype);
- builtin_decl = targetm.vectorize.builtin_mask_for_load ();
- new_stmt = build_function_call_expr (builtin_decl, params);
- new_stmt = build2 (MODIFY_EXPR, vectype, vec_dest, new_stmt);
- new_temp = make_ssa_name (vec_dest, new_stmt);
- TREE_OPERAND (new_stmt, 0) = new_temp;
- new_bb = bsi_insert_on_edge_immediate (pe, new_stmt);
- gcc_assert (!new_bb);
- magic = TREE_OPERAND (new_stmt, 0);
-
- /* Since we have just created a CALL_EXPR, we may need to
- rename call-clobbered variables. */
- mark_call_clobbered_vars_to_rename ();
- }
- else
- {
- /* Use current address instead of init_addr for reduced reg pressure.
- */
- magic = dataref_ptr;
- }
-
-
- /* <4> Create msq = phi <msq_init, lsq> in loop */
- vec_dest = vect_create_destination_var (scalar_dest, vectype);
- msq = make_ssa_name (vec_dest, NULL_TREE);
- phi_stmt = create_phi_node (msq, loop->header); /* CHECKME */
- SSA_NAME_DEF_STMT (msq) = phi_stmt;
- add_phi_arg (phi_stmt, msq_init, loop_preheader_edge (loop));
- add_phi_arg (phi_stmt, lsq, loop_latch_edge (loop));
-
-
- /* <5> Create <vec_dest = realign_load (msq, lsq, magic)> in loop */
- vec_dest = vect_create_destination_var (scalar_dest, vectype);
- new_stmt = build3 (REALIGN_LOAD_EXPR, vectype, msq, lsq, magic);
- new_stmt = build2 (MODIFY_EXPR, vectype, vec_dest, new_stmt);
- new_temp = make_ssa_name (vec_dest, new_stmt);
- TREE_OPERAND (new_stmt, 0) = new_temp;
- vect_finish_stmt_generation (stmt, new_stmt, bsi);
- }
- else
- gcc_unreachable ();
-
- *vec_stmt = new_stmt;
- return true;
-}
-
-
-/* Function vect_supportable_dr_alignment
-
- Return whether the data reference DR is supported with respect to its
- alignment. */
-
-static enum dr_alignment_support
-vect_supportable_dr_alignment (struct data_reference *dr)
-{
- tree vectype = STMT_VINFO_VECTYPE (vinfo_for_stmt (DR_STMT (dr)));
- enum machine_mode mode = (int) TYPE_MODE (vectype);
-
- if (aligned_access_p (dr))
- return dr_aligned;
-
- /* Possibly unaligned access. */
-
- if (DR_IS_READ (dr))
- {
- if (vec_realign_load_optab->handlers[mode].insn_code != CODE_FOR_nothing
- && (!targetm.vectorize.builtin_mask_for_load
- || targetm.vectorize.builtin_mask_for_load ()))
- return dr_unaligned_software_pipeline;
-
- if (movmisalign_optab->handlers[mode].insn_code != CODE_FOR_nothing)
- /* Can't software pipeline the loads, but can at least do them. */
- return dr_unaligned_supported;
- }
-
- /* Unsupported. */
- return dr_unaligned_unsupported;
-}
-
-
-/* Function vect_transform_stmt.
-
- Create a vectorized stmt to replace STMT, and insert it at BSI. */
-
-static bool
-vect_transform_stmt (tree stmt, block_stmt_iterator *bsi)
-{
- bool is_store = false;
- tree vec_stmt = NULL_TREE;
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- bool done;
-
- switch (STMT_VINFO_TYPE (stmt_info))
- {
- case op_vec_info_type:
- done = vectorizable_operation (stmt, bsi, &vec_stmt);
- gcc_assert (done);
- break;
-
- case assignment_vec_info_type:
- done = vectorizable_assignment (stmt, bsi, &vec_stmt);
- gcc_assert (done);
- break;
-
- case load_vec_info_type:
- done = vectorizable_load (stmt, bsi, &vec_stmt);
- gcc_assert (done);
- break;
-
- case store_vec_info_type:
- done = vectorizable_store (stmt, bsi, &vec_stmt);
- gcc_assert (done);
- is_store = true;
- break;
- default:
- if (vect_debug_details (NULL))
- fprintf (dump_file, "stmt not supported.");
- gcc_unreachable ();
- }
-
- STMT_VINFO_VEC_STMT (stmt_info) = vec_stmt;
-
- return is_store;
-}
-
-
-/* This function builds ni_name = number of iterations loop executes
- on the loop preheader. */
-
-static tree
-vect_build_loop_niters (loop_vec_info loop_vinfo)
-{
- tree ni_name, stmt, var;
- edge pe;
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- tree ni = unshare_expr (LOOP_VINFO_NITERS (loop_vinfo));
-
- var = create_tmp_var (TREE_TYPE (ni), "niters");
- add_referenced_tmp_var (var);
- ni_name = force_gimple_operand (ni, &stmt, false, var);
-
- pe = loop_preheader_edge (loop);
- if (stmt)
- {
- basic_block new_bb = bsi_insert_on_edge_immediate (pe, stmt);
- gcc_assert (!new_bb);
- }
-
- return ni_name;
-}
-
-
-/* This function generates the following statements:
-
- ni_name = number of iterations loop executes
- ratio = ni_name / vf
- ratio_mult_vf_name = ratio * vf
-
- and places them at the loop preheader edge. */
-
-static void
-vect_generate_tmps_on_preheader (loop_vec_info loop_vinfo,
- tree *ni_name_ptr,
- tree *ratio_mult_vf_name_ptr,
- tree *ratio_name_ptr)
-{
-
- edge pe;
- basic_block new_bb;
- tree stmt, ni_name;
- tree var;
- tree ratio_name;
- tree ratio_mult_vf_name;
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- tree ni = LOOP_VINFO_NITERS (loop_vinfo);
- int vf = LOOP_VINFO_VECT_FACTOR (loop_vinfo);
- tree log_vf = build_int_cst (unsigned_type_node, exact_log2 (vf));
-
- pe = loop_preheader_edge (loop);
-
- /* Generate temporary variable that contains
- number of iterations loop executes. */
-
- ni_name = vect_build_loop_niters (loop_vinfo);
-
- /* Create: ratio = ni >> log2(vf) */
-
- var = create_tmp_var (TREE_TYPE (ni), "bnd");
- add_referenced_tmp_var (var);
- ratio_name = make_ssa_name (var, NULL_TREE);
- stmt = build2 (MODIFY_EXPR, void_type_node, ratio_name,
- build2 (RSHIFT_EXPR, TREE_TYPE (ni_name), ni_name, log_vf));
- SSA_NAME_DEF_STMT (ratio_name) = stmt;
-
- pe = loop_preheader_edge (loop);
- new_bb = bsi_insert_on_edge_immediate (pe, stmt);
- gcc_assert (!new_bb);
-
- /* Create: ratio_mult_vf = ratio << log2 (vf). */
-
- var = create_tmp_var (TREE_TYPE (ni), "ratio_mult_vf");
- add_referenced_tmp_var (var);
- ratio_mult_vf_name = make_ssa_name (var, NULL_TREE);
- stmt = build2 (MODIFY_EXPR, void_type_node, ratio_mult_vf_name,
- build2 (LSHIFT_EXPR, TREE_TYPE (ratio_name), ratio_name, log_vf));
- SSA_NAME_DEF_STMT (ratio_mult_vf_name) = stmt;
-
- pe = loop_preheader_edge (loop);
- new_bb = bsi_insert_on_edge_immediate (pe, stmt);
- gcc_assert (!new_bb);
-
- *ni_name_ptr = ni_name;
- *ratio_mult_vf_name_ptr = ratio_mult_vf_name;
- *ratio_name_ptr = ratio_name;
-
- return;
-}
-
-
-/* Function vect_update_ivs_after_vectorizer.
-
- "Advance" the induction variables of LOOP to the value they should take
- after the execution of LOOP. This is currently necessary because the
- vectorizer does not handle induction variables that are used after the
- loop. Such a situation occurs when the last iterations of LOOP are
- peeled, because:
- 1. We introduced new uses after LOOP for IVs that were not originally used
- after LOOP: the IVs of LOOP are now used by an epilog loop.
- 2. LOOP is going to be vectorized; this means that it will iterate N/VF
- times, whereas the loop IVs should be bumped N times.
-
- Input:
- - LOOP - a loop that is going to be vectorized. The last few iterations
- of LOOP were peeled.
- - NITERS - the number of iterations that LOOP executes (before it is
- vectorized). i.e, the number of times the ivs should be bumped.
- - UPDATE_E - a successor edge of LOOP->exit that is on the (only) path
- coming out from LOOP on which there are uses of the LOOP ivs
- (this is the path from LOOP->exit to epilog_loop->preheader).
-
- The new definitions of the ivs are placed in LOOP->exit.
- The phi args associated with the edge UPDATE_E in the bb
- UPDATE_E->dest are updated accordingly.
-
- Assumption 1: Like the rest of the vectorizer, this function assumes
- a single loop exit that has a single predecessor.
-
- Assumption 2: The phi nodes in the LOOP header and in update_bb are
- organized in the same order.
-
- Assumption 3: The access function of the ivs is simple enough (see
- vect_can_advance_ivs_p). This assumption will be relaxed in the future.
-
- Assumption 4: Exactly one of the successors of LOOP exit-bb is on a path
- coming out of LOOP on which the ivs of LOOP are used (this is the path
- that leads to the epilog loop; other paths skip the epilog loop). This
- path starts with the edge UPDATE_E, and its destination (denoted update_bb)
- needs to have its phis updated.
- */
-
-static void
-vect_update_ivs_after_vectorizer (struct loop *loop, tree niters, edge update_e)
-{
- basic_block exit_bb = loop->exit_edges[0]->dest;
- tree phi, phi1;
- basic_block update_bb = update_e->dest;
-
- /* gcc_assert (vect_can_advance_ivs_p (loop)); */
-
- /* Make sure there exists a single-predecessor exit bb: */
- gcc_assert (EDGE_COUNT (exit_bb->preds) == 1);
-
- for (phi = phi_nodes (loop->header), phi1 = phi_nodes (update_bb);
- phi && phi1;
- phi = PHI_CHAIN (phi), phi1 = PHI_CHAIN (phi1))
- {
- tree access_fn = NULL;
- tree evolution_part;
- tree init_expr;
- tree step_expr;
- tree var, stmt, ni, ni_name;
- block_stmt_iterator last_bsi;
-
- /* Skip virtual phi's. */
- if (!is_gimple_reg (SSA_NAME_VAR (PHI_RESULT (phi))))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "virtual phi. skip.");
- continue;
- }
-
- access_fn = analyze_scalar_evolution (loop, PHI_RESULT (phi));
- gcc_assert (access_fn);
- evolution_part =
- unshare_expr (evolution_part_in_loop_num (access_fn, loop->num));
- gcc_assert (evolution_part != NULL_TREE);
-
- /* FORNOW: We do not support IVs whose evolution function is a polynomial
- of degree >= 2 or exponential. */
- gcc_assert (!tree_is_chrec (evolution_part));
-
- step_expr = evolution_part;
- init_expr = unshare_expr (initial_condition (access_fn));
-
- ni = build2 (PLUS_EXPR, TREE_TYPE (init_expr),
- build2 (MULT_EXPR, TREE_TYPE (niters),
- niters, step_expr), init_expr);
-
- var = create_tmp_var (TREE_TYPE (init_expr), "tmp");
- add_referenced_tmp_var (var);
-
- ni_name = force_gimple_operand (ni, &stmt, false, var);
-
- /* Insert stmt into exit_bb. */
- last_bsi = bsi_last (exit_bb);
- if (stmt)
- bsi_insert_before (&last_bsi, stmt, BSI_SAME_STMT);
-
- /* Fix phi expressions in the successor bb. */
- gcc_assert (PHI_ARG_DEF_FROM_EDGE (phi1, update_e) ==
- PHI_ARG_DEF_FROM_EDGE (phi, EDGE_SUCC (loop->latch, 0)));
- SET_PHI_ARG_DEF (phi1, phi_arg_from_edge (phi1, update_e), ni_name);
- }
-}
-
-
-/* Function vect_do_peeling_for_loop_bound
-
- Peel the last iterations of the loop represented by LOOP_VINFO.
- The peeled iterations form a new epilog loop. Given that the loop now
- iterates NITERS times, the new epilog loop iterates
- NITERS % VECTORIZATION_FACTOR times.
-
- The original loop will later be made to iterate
- NITERS / VECTORIZATION_FACTOR times (this value is placed into RATIO). */
-
-static void
-vect_do_peeling_for_loop_bound (loop_vec_info loop_vinfo, tree *ratio,
- struct loops *loops)
-{
-
- tree ni_name, ratio_mult_vf_name;
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- struct loop *new_loop;
- edge update_e;
-#ifdef ENABLE_CHECKING
- int loop_num;
-#endif
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "\n<<vect_transtorm_for_unknown_loop_bound>>\n");
-
- /* Generate the following variables on the preheader of original loop:
-
- ni_name = number of iteration the original loop executes
- ratio = ni_name / vf
- ratio_mult_vf_name = ratio * vf */
- vect_generate_tmps_on_preheader (loop_vinfo, &ni_name,
- &ratio_mult_vf_name, ratio);
-
- /* Update loop info. */
- loop->pre_header = loop_preheader_edge (loop)->src;
- loop->pre_header_edges[0] = loop_preheader_edge (loop);
-
-#ifdef ENABLE_CHECKING
- loop_num = loop->num;
-#endif
- new_loop = slpeel_tree_peel_loop_to_edge (loop, loops, loop->exit_edges[0],
- ratio_mult_vf_name, ni_name, false);
-#ifdef ENABLE_CHECKING
- gcc_assert (new_loop);
- gcc_assert (loop_num == loop->num);
- slpeel_verify_cfg_after_peeling (loop, new_loop);
-#endif
-
- /* A guard that controls whether the new_loop is to be executed or skipped
- is placed in LOOP->exit. LOOP->exit therefore has two successors - one
- is the preheader of NEW_LOOP, where the IVs from LOOP are used. The other
- is a bb after NEW_LOOP, where these IVs are not used. Find the edge that
- is on the path where the LOOP IVs are used and need to be updated. */
-
- if (EDGE_PRED (new_loop->pre_header, 0)->src == loop->exit_edges[0]->dest)
- update_e = EDGE_PRED (new_loop->pre_header, 0);
- else
- update_e = EDGE_PRED (new_loop->pre_header, 1);
-
- /* Update IVs of original loop as if they were advanced
- by ratio_mult_vf_name steps. */
- vect_update_ivs_after_vectorizer (loop, ratio_mult_vf_name, update_e);
-
- /* After peeling we have to reset scalar evolution analyzer. */
- scev_reset ();
-
- return;
-}
-
-
-/* Function vect_gen_niters_for_prolog_loop
-
- Set the number of iterations for the loop represented by LOOP_VINFO
- to the minimum between LOOP_NITERS (the original iteration count of the loop)
- and the misalignment of DR - the first data reference recorded in
- LOOP_VINFO_UNALIGNED_DR (LOOP_VINFO). As a result, after the execution of
- this loop, the data reference DR will refer to an aligned location.
-
- The following computation is generated:
-
- compute address misalignment in bytes:
- addr_mis = addr & (vectype_size - 1)
-
- prolog_niters = min ( LOOP_NITERS , (VF - addr_mis/elem_size)&(VF-1) )
-
- (elem_size = element type size; an element is the scalar element
- whose type is the inner type of the vectype) */
-
-static tree
-vect_gen_niters_for_prolog_loop (loop_vec_info loop_vinfo, tree loop_niters)
-{
- struct data_reference *dr = LOOP_VINFO_UNALIGNED_DR (loop_vinfo);
- int vf = LOOP_VINFO_VECT_FACTOR (loop_vinfo);
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- tree var, stmt;
- tree iters, iters_name;
- edge pe;
- basic_block new_bb;
- tree dr_stmt = DR_STMT (dr);
- stmt_vec_info stmt_info = vinfo_for_stmt (dr_stmt);
- tree vectype = STMT_VINFO_VECTYPE (stmt_info);
- int vectype_align = TYPE_ALIGN (vectype) / BITS_PER_UNIT;
- tree elem_misalign;
- tree byte_misalign;
- tree new_stmts = NULL_TREE;
- tree start_addr =
- vect_create_addr_base_for_vector_ref (dr_stmt, &new_stmts, NULL_TREE);
- tree ptr_type = TREE_TYPE (start_addr);
- tree size = TYPE_SIZE (ptr_type);
- tree type = lang_hooks.types.type_for_size (tree_low_cst (size, 1), 1);
- tree vectype_size_minus_1 = build_int_cst (type, vectype_align - 1);
- tree vf_minus_1 = build_int_cst (unsigned_type_node, vf - 1);
- tree niters_type = TREE_TYPE (loop_niters);
- tree elem_size_log =
- build_int_cst (unsigned_type_node, exact_log2 (vectype_align/vf));
- tree vf_tree = build_int_cst (unsigned_type_node, vf);
-
- pe = loop_preheader_edge (loop);
- new_bb = bsi_insert_on_edge_immediate (pe, new_stmts);
- gcc_assert (!new_bb);
-
- /* Create: byte_misalign = addr & (vectype_size - 1) */
- byte_misalign = build2 (BIT_AND_EXPR, type, start_addr, vectype_size_minus_1);
-
- /* Create: elem_misalign = byte_misalign / element_size */
- elem_misalign =
- build2 (RSHIFT_EXPR, unsigned_type_node, byte_misalign, elem_size_log);
-
- /* Create: (niters_type) (VF - elem_misalign)&(VF - 1) */
- iters = build2 (MINUS_EXPR, unsigned_type_node, vf_tree, elem_misalign);
- iters = build2 (BIT_AND_EXPR, unsigned_type_node, iters, vf_minus_1);
- iters = fold_convert (niters_type, iters);
-
- /* Create: prolog_loop_niters = min (iters, loop_niters) */
- /* If the loop bound is known at compile time we already verified that it is
- greater than vf; since the misalignment ('iters') is at most vf, there's
- no need to generate the MIN_EXPR in this case. */
- if (!host_integerp (loop_niters, 0))
- iters = build2 (MIN_EXPR, niters_type, iters, loop_niters);
-
- var = create_tmp_var (niters_type, "prolog_loop_niters");
- add_referenced_tmp_var (var);
- iters_name = force_gimple_operand (iters, &stmt, false, var);
-
- /* Insert stmt on loop preheader edge. */
- pe = loop_preheader_edge (loop);
- if (stmt)
- {
- basic_block new_bb = bsi_insert_on_edge_immediate (pe, stmt);
- gcc_assert (!new_bb);
- }
-
- return iters_name;
-}
-
-
-/* Function vect_update_inits_of_dr
-
- NITERS iterations were peeled from LOOP. DR represents a data reference
- in LOOP. This function updates the information recorded in DR to
- account for the fact that the first NITERS iterations had already been
- executed. Specifically, it updates the initial_condition of the
- access_function of DR. */
-
-static void
-vect_update_inits_of_dr (struct data_reference *dr, struct loop *loop,
- tree niters)
-{
- tree access_fn = DR_ACCESS_FN (dr, 0);
- tree init, init_new, step;
-
- step = evolution_part_in_loop_num (access_fn, loop->num);
- init = initial_condition (access_fn);
-
- init_new = build2 (PLUS_EXPR, TREE_TYPE (init),
- build2 (MULT_EXPR, TREE_TYPE (niters),
- niters, step), init);
- DR_ACCESS_FN (dr, 0) = chrec_replace_initial_condition (access_fn, init_new);
-
- return;
-}
-
-
-/* Function vect_update_inits_of_drs
-
- NITERS iterations were peeled from the loop represented by LOOP_VINFO.
- This function updates the information recorded for the data references in
- the loop to account for the fact that the first NITERS iterations had
- already been executed. Specifically, it updates the initial_condition of the
- access_function of all the data_references in the loop. */
-
-static void
-vect_update_inits_of_drs (loop_vec_info loop_vinfo, tree niters)
-{
- unsigned int i;
- varray_type loop_write_datarefs = LOOP_VINFO_DATAREF_WRITES (loop_vinfo);
- varray_type loop_read_datarefs = LOOP_VINFO_DATAREF_READS (loop_vinfo);
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
-
- if (dump_file && (dump_flags & TDF_DETAILS))
- fprintf (dump_file, "\n<<vect_update_inits_of_dr>>\n");
-
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_write_datarefs); i++)
- {
- struct data_reference *dr = VARRAY_GENERIC_PTR (loop_write_datarefs, i);
- vect_update_inits_of_dr (dr, loop, niters);
- }
-
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_read_datarefs); i++)
- {
- struct data_reference *dr = VARRAY_GENERIC_PTR (loop_read_datarefs, i);
- vect_update_inits_of_dr (dr, loop, niters);
- }
-}
-
-
-/* Function vect_do_peeling_for_alignment
-
- Peel the first 'niters' iterations of the loop represented by LOOP_VINFO.
- 'niters' is set to the misalignment of one of the data references in the
- loop, thereby forcing it to refer to an aligned location at the beginning
- of the execution of this loop. The data reference for which we are
- peeling is recorded in LOOP_VINFO_UNALIGNED_DR. */
-
-static void
-vect_do_peeling_for_alignment (loop_vec_info loop_vinfo, struct loops *loops)
-{
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- tree niters_of_prolog_loop, ni_name;
- tree n_iters;
- struct loop *new_loop;
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "\n<<vect_do_peeling_for_alignment>>\n");
-
- ni_name = vect_build_loop_niters (loop_vinfo);
- niters_of_prolog_loop = vect_gen_niters_for_prolog_loop (loop_vinfo, ni_name);
-
- /* Peel the prolog loop and iterate it niters_of_prolog_loop. */
- new_loop =
- slpeel_tree_peel_loop_to_edge (loop, loops, loop_preheader_edge (loop),
- niters_of_prolog_loop, ni_name, true);
-#ifdef ENABLE_CHECKING
- gcc_assert (new_loop);
- slpeel_verify_cfg_after_peeling (new_loop, loop);
-#endif
-
- /* Update number of times loop executes. */
- n_iters = LOOP_VINFO_NITERS (loop_vinfo);
- LOOP_VINFO_NITERS (loop_vinfo) =
- build2 (MINUS_EXPR, TREE_TYPE (n_iters), n_iters, niters_of_prolog_loop);
-
- /* Update the init conditions of the access functions of all data refs. */
- vect_update_inits_of_drs (loop_vinfo, niters_of_prolog_loop);
-
- /* After peeling we have to reset scalar evolution analyzer. */
- scev_reset ();
-
- return;
-}
-
-
-/* Function vect_transform_loop.
-
- The analysis phase has determined that the loop is vectorizable.
- Vectorize the loop - created vectorized stmts to replace the scalar
- stmts in the loop, and update the loop exit condition. */
-
-static void
-vect_transform_loop (loop_vec_info loop_vinfo,
- struct loops *loops ATTRIBUTE_UNUSED)
-{
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- basic_block *bbs = LOOP_VINFO_BBS (loop_vinfo);
- int nbbs = loop->num_nodes;
- block_stmt_iterator si;
- int i;
- tree ratio = NULL;
- int vectorization_factor = LOOP_VINFO_VECT_FACTOR (loop_vinfo);
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "\n<<vec_transform_loop>>\n");
-
-
- /* Peel the loop if there are data refs with unknown alignment.
- Only one data ref with unknown store is allowed. */
-
- if (LOOP_DO_PEELING_FOR_ALIGNMENT (loop_vinfo))
- vect_do_peeling_for_alignment (loop_vinfo, loops);
-
- /* If the loop has a symbolic number of iterations 'n' (i.e. it's not a
- compile time constant), or it is a constant that doesn't divide by the
- vectorization factor, then an epilog loop needs to be created.
- We therefore duplicate the loop: the original loop will be vectorized,
- and will compute the first (n/VF) iterations. The second copy of the loop
- will remain scalar and will compute the remaining (n%VF) iterations.
- (VF is the vectorization factor). */
-
- if (!LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo)
- || (LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo)
- && LOOP_VINFO_INT_NITERS (loop_vinfo) % vectorization_factor != 0))
- vect_do_peeling_for_loop_bound (loop_vinfo, &ratio, loops);
- else
- ratio = build_int_cst (TREE_TYPE (LOOP_VINFO_NITERS (loop_vinfo)),
- LOOP_VINFO_INT_NITERS (loop_vinfo) / vectorization_factor);
-
- /* 1) Make sure the loop header has exactly two entries
- 2) Make sure we have a preheader basic block. */
-
- gcc_assert (EDGE_COUNT (loop->header->preds) == 2);
-
- loop_split_edge_with (loop_preheader_edge (loop), NULL);
-
-
- /* FORNOW: the vectorizer supports only loops which body consist
- of one basic block (header + empty latch). When the vectorizer will
- support more involved loop forms, the order by which the BBs are
- traversed need to be reconsidered. */
-
- for (i = 0; i < nbbs; i++)
- {
- basic_block bb = bbs[i];
-
- for (si = bsi_start (bb); !bsi_end_p (si);)
- {
- tree stmt = bsi_stmt (si);
- stmt_vec_info stmt_info;
- bool is_store;
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "------>vectorizing statement: ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
- stmt_info = vinfo_for_stmt (stmt);
- gcc_assert (stmt_info);
- if (!STMT_VINFO_RELEVANT_P (stmt_info))
- {
- bsi_next (&si);
- continue;
- }
-#ifdef ENABLE_CHECKING
- /* FORNOW: Verify that all stmts operate on the same number of
- units and no inner unrolling is necessary. */
- gcc_assert
- (GET_MODE_NUNITS (TYPE_MODE (STMT_VINFO_VECTYPE (stmt_info)))
- == vectorization_factor);
-#endif
- /* -------- vectorize statement ------------ */
- if (vect_debug_details (NULL))
- fprintf (dump_file, "transform statement.");
-
- is_store = vect_transform_stmt (stmt, &si);
- if (is_store)
- {
- /* free the attached stmt_vec_info and remove the stmt. */
- stmt_ann_t ann = stmt_ann (stmt);
- free (stmt_info);
- set_stmt_info (ann, NULL);
- bsi_remove (&si);
- continue;
- }
-
- bsi_next (&si);
- } /* stmts in BB */
- } /* BBs in loop */
-
- slpeel_make_loop_iterate_ntimes (loop, ratio);
-
- if (vect_debug_details (loop))
- fprintf (dump_file,"Success! loop vectorized.");
- if (vect_debug_stats (loop))
- fprintf (dump_file, "LOOP VECTORIZED.");
-}
-
-
-/* Function vect_is_simple_use.
-
- Input:
- LOOP - the loop that is being vectorized.
- OPERAND - operand of a stmt in LOOP.
- DEF - the defining stmt in case OPERAND is an SSA_NAME.
-
- Returns whether a stmt with OPERAND can be vectorized.
- Supportable operands are constants, loop invariants, and operands that are
- defined by the current iteration of the loop. Unsupportable operands are
- those that are defined by a previous iteration of the loop (as is the case
- in reduction/induction computations). */
-
-static bool
-vect_is_simple_use (tree operand, struct loop *loop, tree *def)
-{
- tree def_stmt;
- basic_block bb;
-
- if (def)
- *def = NULL_TREE;
-
- if (TREE_CODE (operand) == INTEGER_CST || TREE_CODE (operand) == REAL_CST)
- return true;
-
- if (TREE_CODE (operand) != SSA_NAME)
- return false;
-
- def_stmt = SSA_NAME_DEF_STMT (operand);
- if (def_stmt == NULL_TREE )
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "no def_stmt.");
- return false;
- }
-
- /* empty stmt is expected only in case of a function argument.
- (Otherwise - we expect a phi_node or a modify_expr). */
- if (IS_EMPTY_STMT (def_stmt))
- {
- tree arg = TREE_OPERAND (def_stmt, 0);
- if (TREE_CODE (arg) == INTEGER_CST || TREE_CODE (arg) == REAL_CST)
- return true;
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "Unexpected empty stmt: ");
- print_generic_expr (dump_file, def_stmt, TDF_SLIM);
- }
- return false;
- }
-
- /* phi_node inside the loop indicates an induction/reduction pattern.
- This is not supported yet. */
- bb = bb_for_stmt (def_stmt);
- if (TREE_CODE (def_stmt) == PHI_NODE && flow_bb_inside_loop_p (loop, bb))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "reduction/induction - unsupported.");
- return false; /* FORNOW: not supported yet. */
- }
-
- /* Expecting a modify_expr or a phi_node. */
- if (TREE_CODE (def_stmt) == MODIFY_EXPR
- || TREE_CODE (def_stmt) == PHI_NODE)
- {
- if (def)
- *def = def_stmt;
- return true;
- }
-
- return false;
-}
-
-
-/* Function vect_analyze_operations.
-
- Scan the loop stmts and make sure they are all vectorizable. */
-
-static bool
-vect_analyze_operations (loop_vec_info loop_vinfo)
-{
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- basic_block *bbs = LOOP_VINFO_BBS (loop_vinfo);
- int nbbs = loop->num_nodes;
- block_stmt_iterator si;
- unsigned int vectorization_factor = 0;
- int i;
- bool ok;
- tree scalar_type;
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "\n<<vect_analyze_operations>>\n");
-
- for (i = 0; i < nbbs; i++)
- {
- basic_block bb = bbs[i];
-
- for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
- {
- tree stmt = bsi_stmt (si);
- unsigned int nunits;
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- tree vectype;
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "==> examining statement: ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
-
- gcc_assert (stmt_info);
-
- /* skip stmts which do not need to be vectorized.
- this is expected to include:
- - the COND_EXPR which is the loop exit condition
- - any LABEL_EXPRs in the loop
- - computations that are used only for array indexing or loop
- control */
-
- if (!STMT_VINFO_RELEVANT_P (stmt_info))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "irrelevant.");
- continue;
- }
-
- if (VECTOR_MODE_P (TYPE_MODE (TREE_TYPE (stmt))))
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- {
- fprintf (dump_file, "not vectorized: vector stmt in loop:");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
- return false;
- }
-
- if (STMT_VINFO_DATA_REF (stmt_info))
- scalar_type = TREE_TYPE (DR_REF (STMT_VINFO_DATA_REF (stmt_info)));
- else if (TREE_CODE (stmt) == MODIFY_EXPR)
- scalar_type = TREE_TYPE (TREE_OPERAND (stmt, 0));
- else
- scalar_type = TREE_TYPE (stmt);
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "get vectype for scalar type: ");
- print_generic_expr (dump_file, scalar_type, TDF_SLIM);
- }
-
- vectype = get_vectype_for_scalar_type (scalar_type);
- if (!vectype)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- {
- fprintf (dump_file, "not vectorized: unsupported data-type ");
- print_generic_expr (dump_file, scalar_type, TDF_SLIM);
- }
- return false;
- }
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "vectype: ");
- print_generic_expr (dump_file, vectype, TDF_SLIM);
- }
- STMT_VINFO_VECTYPE (stmt_info) = vectype;
-
- ok = (vectorizable_operation (stmt, NULL, NULL)
- || vectorizable_assignment (stmt, NULL, NULL)
- || vectorizable_load (stmt, NULL, NULL)
- || vectorizable_store (stmt, NULL, NULL));
-
- if (!ok)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- {
- fprintf (dump_file, "not vectorized: stmt not supported: ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
- return false;
- }
-
- nunits = GET_MODE_NUNITS (TYPE_MODE (vectype));
- if (vect_debug_details (NULL))
- fprintf (dump_file, "nunits = %d", nunits);
-
- if (vectorization_factor)
- {
- /* FORNOW: don't allow mixed units.
- This restriction will be relaxed in the future. */
- if (nunits != vectorization_factor)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: mixed data-types");
- return false;
- }
- }
- else
- vectorization_factor = nunits;
-
-#ifdef ENABLE_CHECKING
- gcc_assert (GET_MODE_SIZE (TYPE_MODE (scalar_type))
- * vectorization_factor == UNITS_PER_SIMD_WORD);
-#endif
- }
- }
-
- /* TODO: Analyze cost. Decide if worth while to vectorize. */
-
- if (vectorization_factor <= 1)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: unsupported data-type");
- return false;
- }
- LOOP_VINFO_VECT_FACTOR (loop_vinfo) = vectorization_factor;
-
- if (LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo) && vect_debug_details (NULL))
- fprintf (dump_file,
- "vectorization_factor = %d, niters = " HOST_WIDE_INT_PRINT_DEC,
- vectorization_factor, LOOP_VINFO_INT_NITERS (loop_vinfo));
-
- if (LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo)
- && LOOP_VINFO_INT_NITERS (loop_vinfo) < vectorization_factor)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: iteration count too small.");
- return false;
- }
-
- if (!LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo)
- || LOOP_VINFO_INT_NITERS (loop_vinfo) % vectorization_factor != 0)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "epilog loop required.");
- if (!vect_can_advance_ivs_p (loop))
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: can't create epilog loop 1.");
- return false;
- }
- if (!slpeel_can_duplicate_loop_p (loop, loop->exit_edges[0]))
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: can't create epilog loop 2.");
- return false;
- }
- }
-
- return true;
-}
-
-
-/* Function exist_non_indexing_operands_for_use_p
-
- USE is one of the uses attached to STMT. Check if USE is
- used in STMT for anything other than indexing an array. */
-
-static bool
-exist_non_indexing_operands_for_use_p (tree use, tree stmt)
-{
- tree operand;
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
-
- /* USE corresponds to some operand in STMT. If there is no data
- reference in STMT, then any operand that corresponds to USE
- is not indexing an array. */
- if (!STMT_VINFO_DATA_REF (stmt_info))
- return true;
-
- /* STMT has a data_ref. FORNOW this means that its of one of
- the following forms:
- -1- ARRAY_REF = var
- -2- var = ARRAY_REF
- (This should have been verified in analyze_data_refs).
-
- 'var' in the second case corresponds to a def, not a use,
- so USE cannot correspond to any operands that are not used
- for array indexing.
-
- Therefore, all we need to check is if STMT falls into the
- first case, and whether var corresponds to USE. */
-
- if (TREE_CODE (TREE_OPERAND (stmt, 0)) == SSA_NAME)
- return false;
-
- operand = TREE_OPERAND (stmt, 1);
-
- if (TREE_CODE (operand) != SSA_NAME)
- return false;
-
- if (operand == use)
- return true;
-
- return false;
-}
-
-
-/* Function vect_is_simple_iv_evolution.
-
- FORNOW: A simple evolution of an induction variables in the loop is
- considered a polynomial evolution with constant step. */
-
-static bool
-vect_is_simple_iv_evolution (unsigned loop_nb, tree access_fn, tree * init,
- tree * step, bool strict)
-{
- tree init_expr;
- tree step_expr;
-
- tree evolution_part = evolution_part_in_loop_num (access_fn, loop_nb);
-
- /* When there is no evolution in this loop, the evolution function
- is not "simple". */
- if (evolution_part == NULL_TREE)
- return false;
-
- /* When the evolution is a polynomial of degree >= 2
- the evolution function is not "simple". */
- if (tree_is_chrec (evolution_part))
- return false;
-
- step_expr = evolution_part;
- init_expr = unshare_expr (initial_condition (access_fn));
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "step: ");
- print_generic_expr (dump_file, step_expr, TDF_SLIM);
- fprintf (dump_file, ", init: ");
- print_generic_expr (dump_file, init_expr, TDF_SLIM);
- }
-
- *init = init_expr;
- *step = step_expr;
-
- if (TREE_CODE (step_expr) != INTEGER_CST)
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "step unknown.");
- return false;
- }
-
- if (strict)
- if (!integer_onep (step_expr))
- {
- if (vect_debug_details (NULL))
- print_generic_expr (dump_file, step_expr, TDF_SLIM);
- return false;
- }
-
- return true;
-}
-
-
-/* Function vect_analyze_scalar_cycles.
-
- Examine the cross iteration def-use cycles of scalar variables, by
- analyzing the loop (scalar) PHIs; verify that the cross iteration def-use
- cycles that they represent do not impede vectorization.
-
- FORNOW: Reduction as in the following loop, is not supported yet:
- loop1:
- for (i=0; i<N; i++)
- sum += a[i];
- The cross-iteration cycle corresponding to variable 'sum' will be
- considered too complicated and will impede vectorization.
-
- FORNOW: Induction as in the following loop, is not supported yet:
- loop2:
- for (i=0; i<N; i++)
- a[i] = i;
-
- However, the following loop *is* vectorizable:
- loop3:
- for (i=0; i<N; i++)
- a[i] = b[i];
-
- In both loops there exists a def-use cycle for the variable i:
- loop: i_2 = PHI (i_0, i_1)
- a[i_2] = ...;
- i_1 = i_2 + 1;
- GOTO loop;
-
- The evolution of the above cycle is considered simple enough,
- however, we also check that the cycle does not need to be
- vectorized, i.e - we check that the variable that this cycle
- defines is only used for array indexing or in stmts that do not
- need to be vectorized. This is not the case in loop2, but it
- *is* the case in loop3. */
-
-static bool
-vect_analyze_scalar_cycles (loop_vec_info loop_vinfo)
-{
- tree phi;
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- basic_block bb = loop->header;
- tree dummy;
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "\n<<vect_analyze_scalar_cycles>>\n");
-
- for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
- {
- tree access_fn = NULL;
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "Analyze phi: ");
- print_generic_expr (dump_file, phi, TDF_SLIM);
- }
-
- /* Skip virtual phi's. The data dependences that are associated with
- virtual defs/uses (i.e., memory accesses) are analyzed elsewhere. */
-
- if (!is_gimple_reg (SSA_NAME_VAR (PHI_RESULT (phi))))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "virtual phi. skip.");
- continue;
- }
-
- /* Analyze the evolution function. */
-
- /* FORNOW: The only scalar cross-iteration cycles that we allow are
- those of loop induction variables; This property is verified here.
-
- Furthermore, if that induction variable is used in an operation
- that needs to be vectorized (i.e, is not solely used to index
- arrays and check the exit condition) - we do not support its
- vectorization yet. This property is verified in vect_is_simple_use,
- during vect_analyze_operations. */
-
- access_fn = /* instantiate_parameters
- (loop,*/
- analyze_scalar_evolution (loop, PHI_RESULT (phi));
-
- if (!access_fn)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: unsupported scalar cycle.");
- return false;
- }
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "Access function of PHI: ");
- print_generic_expr (dump_file, access_fn, TDF_SLIM);
- }
-
- if (!vect_is_simple_iv_evolution (loop->num, access_fn, &dummy,
- &dummy, false))
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: unsupported scalar cycle.");
- return false;
- }
- }
-
- return true;
-}
-
-
-/* Function vect_analyze_data_ref_dependence.
-
- Return TRUE if there (might) exist a dependence between a memory-reference
- DRA and a memory-reference DRB. */
-
-static bool
-vect_analyze_data_ref_dependence (struct data_reference *dra,
- struct data_reference *drb,
- struct loop *loop)
-{
- bool differ_p;
- struct data_dependence_relation *ddr;
-
- if (!array_base_name_differ_p (dra, drb, &differ_p))
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- {
- fprintf (dump_file,
- "not vectorized: can't determine dependence between: ");
- print_generic_expr (dump_file, DR_REF (dra), TDF_SLIM);
- fprintf (dump_file, " and ");
- print_generic_expr (dump_file, DR_REF (drb), TDF_SLIM);
- }
- return true;
- }
-
- if (differ_p)
- return false;
-
- ddr = initialize_data_dependence_relation (dra, drb);
- compute_affine_dependence (ddr);
-
- if (DDR_ARE_DEPENDENT (ddr) == chrec_known)
- return false;
-
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- {
- fprintf (dump_file,
- "not vectorized: possible dependence between data-refs ");
- print_generic_expr (dump_file, DR_REF (dra), TDF_SLIM);
- fprintf (dump_file, " and ");
- print_generic_expr (dump_file, DR_REF (drb), TDF_SLIM);
- }
-
- return true;
-}
-
-
-/* Function vect_analyze_data_ref_dependences.
-
- Examine all the data references in the loop, and make sure there do not
- exist any data dependences between them.
-
- TODO: dependences which distance is greater than the vectorization factor
- can be ignored. */
-
-static bool
-vect_analyze_data_ref_dependences (loop_vec_info loop_vinfo)
-{
- unsigned int i, j;
- varray_type loop_write_refs = LOOP_VINFO_DATAREF_WRITES (loop_vinfo);
- varray_type loop_read_refs = LOOP_VINFO_DATAREF_READS (loop_vinfo);
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
-
- /* Examine store-store (output) dependences. */
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "\n<<vect_analyze_dependences>>\n");
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "compare all store-store pairs.");
-
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_write_refs); i++)
- {
- for (j = i + 1; j < VARRAY_ACTIVE_SIZE (loop_write_refs); j++)
- {
- struct data_reference *dra =
- VARRAY_GENERIC_PTR (loop_write_refs, i);
- struct data_reference *drb =
- VARRAY_GENERIC_PTR (loop_write_refs, j);
- if (vect_analyze_data_ref_dependence (dra, drb, loop))
- return false;
- }
- }
-
- /* Examine load-store (true/anti) dependences. */
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "compare all load-store pairs.");
-
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_read_refs); i++)
- {
- for (j = 0; j < VARRAY_ACTIVE_SIZE (loop_write_refs); j++)
- {
- struct data_reference *dra = VARRAY_GENERIC_PTR (loop_read_refs, i);
- struct data_reference *drb =
- VARRAY_GENERIC_PTR (loop_write_refs, j);
- if (vect_analyze_data_ref_dependence (dra, drb, loop))
- return false;
- }
- }
-
- return true;
-}
-
-
-/* Function vect_get_first_index.
-
- REF is a data reference.
- If it is an ARRAY_REF: if its lower bound is simple enough,
- put it in ARRAY_FIRST_INDEX and return TRUE; otherwise - return FALSE.
- If it is not an ARRAY_REF: REF has no "first index";
- ARRAY_FIRST_INDEX in zero, and the function returns TRUE. */
-
-static bool
-vect_get_first_index (tree ref, tree *array_first_index)
-{
- tree array_start;
-
- if (TREE_CODE (ref) != ARRAY_REF)
- *array_first_index = size_zero_node;
- else
- {
- array_start = array_ref_low_bound (ref);
- if (!host_integerp (array_start, 0))
- {
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "array min val not simple integer cst.");
- print_generic_expr (dump_file, array_start, TDF_DETAILS);
- }
- return false;
- }
- *array_first_index = array_start;
- }
-
- return true;
-}
-
-
-/* Function vect_compute_array_base_alignment.
- A utility function of vect_compute_array_ref_alignment.
-
- Compute the misalignment of ARRAY in bits.
-
- Input:
- ARRAY - an array_ref (possibly multidimensional) of type ARRAY_TYPE.
- VECTYPE - we are interested in the misalignment modulo the size of vectype.
- if NULL: don't compute misalignment, just return the base of ARRAY.
- PREV_DIMENSIONS - initialized to one.
- MISALIGNMENT - the computed misalignment in bits.
-
- Output:
- If VECTYPE is not NULL:
- Return NULL_TREE if the misalignment cannot be computed. Otherwise, return
- the base of the array, and put the computed misalignment in MISALIGNMENT.
- If VECTYPE is NULL:
- Return the base of the array.
-
- For a[idx_N]...[idx_2][idx_1][idx_0], the address of
- a[idx_N]...[idx_2][idx_1] is
- {&a + idx_1 * dim_0 + idx_2 * dim_0 * dim_1 + ...
- ... + idx_N * dim_0 * ... * dim_N-1}.
- (The misalignment of &a is not checked here).
- Note, that every term contains dim_0, therefore, if dim_0 is a
- multiple of NUNITS, the whole sum is a multiple of NUNITS.
- Otherwise, if idx_1 is constant, and dim_1 is a multiple of
- NUINTS, we can say that the misalignment of the sum is equal to
- the misalignment of {idx_1 * dim_0}. If idx_1 is not constant,
- we can't determine this array misalignment, and we return
- false.
- We proceed recursively in this manner, accumulating total misalignment
- and the multiplication of previous dimensions for correct misalignment
- calculation. */
-
-static tree
-vect_compute_array_base_alignment (tree array,
- tree vectype,
- tree *prev_dimensions,
- tree *misalignment)
-{
- tree index;
- tree domain;
- tree dimension_size;
- tree mis;
- tree bits_per_vectype;
- tree bits_per_vectype_unit;
-
- /* The 'stop condition' of the recursion. */
- if (TREE_CODE (array) != ARRAY_REF)
- return array;
-
- if (!vectype)
- /* Just get the base decl. */
- return vect_compute_array_base_alignment
- (TREE_OPERAND (array, 0), NULL, NULL, NULL);
-
- if (!host_integerp (*misalignment, 1) || TREE_OVERFLOW (*misalignment) ||
- !host_integerp (*prev_dimensions, 1) || TREE_OVERFLOW (*prev_dimensions))
- return NULL_TREE;
-
- domain = TYPE_DOMAIN (TREE_TYPE (array));
- dimension_size =
- int_const_binop (PLUS_EXPR,
- int_const_binop (MINUS_EXPR, TYPE_MAX_VALUE (domain),
- TYPE_MIN_VALUE (domain), 1),
- size_one_node, 1);
-
- /* Check if the dimension size is a multiple of NUNITS, the remaining sum
- is a multiple of NUNITS:
-
- dimension_size % GET_MODE_NUNITS (TYPE_MODE (vectype)) == 0 ?
- */
- mis = int_const_binop (TRUNC_MOD_EXPR, dimension_size,
- build_int_cst (NULL_TREE, GET_MODE_NUNITS (TYPE_MODE (vectype))), 1);
- if (integer_zerop (mis))
- /* This array is aligned. Continue just in order to get the base decl. */
- return vect_compute_array_base_alignment
- (TREE_OPERAND (array, 0), NULL, NULL, NULL);
-
- index = TREE_OPERAND (array, 1);
- if (!host_integerp (index, 1))
- /* The current index is not constant. */
- return NULL_TREE;
-
- index = int_const_binop (MINUS_EXPR, index, TYPE_MIN_VALUE (domain), 0);
-
- bits_per_vectype = fold_convert (unsigned_type_node,
- build_int_cst (NULL_TREE, BITS_PER_UNIT *
- GET_MODE_SIZE (TYPE_MODE (vectype))));
- bits_per_vectype_unit = fold_convert (unsigned_type_node,
- build_int_cst (NULL_TREE, BITS_PER_UNIT *
- GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (vectype)))));
-
- /* Add {idx_i * dim_i-1 * ... * dim_0 } to the misalignment computed
- earlier:
-
- *misalignment =
- (*misalignment + index_val * dimension_size * *prev_dimensions)
- % vectype_nunits;
- */
-
- mis = int_const_binop (MULT_EXPR, index, dimension_size, 1);
- mis = int_const_binop (MULT_EXPR, mis, *prev_dimensions, 1);
- mis = int_const_binop (MULT_EXPR, mis, bits_per_vectype_unit, 1);
- mis = int_const_binop (PLUS_EXPR, *misalignment, mis, 1);
- *misalignment = int_const_binop (TRUNC_MOD_EXPR, mis, bits_per_vectype, 1);
-
-
- *prev_dimensions = int_const_binop (MULT_EXPR,
- *prev_dimensions, dimension_size, 1);
-
- return vect_compute_array_base_alignment (TREE_OPERAND (array, 0), vectype,
- prev_dimensions,
- misalignment);
-}
-
-
-/* Function vect_compute_data_ref_alignment
-
- Compute the misalignment of the data reference DR.
-
- Output:
- 1. If during the misalignment computation it is found that the data reference
- cannot be vectorized then false is returned.
- 2. DR_MISALIGNMENT (DR) is defined.
-
- FOR NOW: No analysis is actually performed. Misalignment is calculated
- only for trivial cases. TODO. */
-
-static bool
-vect_compute_data_ref_alignment (struct data_reference *dr,
- loop_vec_info loop_vinfo)
-{
- tree stmt = DR_STMT (dr);
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- tree ref = DR_REF (dr);
- tree vectype;
- tree scalar_type;
- tree offset = size_zero_node;
- tree base, bit_offset, alignment;
- tree unit_bits = fold_convert (unsigned_type_node,
- build_int_cst (NULL_TREE, BITS_PER_UNIT));
- tree dr_base;
- bool base_aligned_p;
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "vect_compute_data_ref_alignment:");
-
- /* Initialize misalignment to unknown. */
- DR_MISALIGNMENT (dr) = -1;
-
- scalar_type = TREE_TYPE (ref);
- vectype = get_vectype_for_scalar_type (scalar_type);
- if (!vectype)
- {
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "no vectype for stmt: ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- fprintf (dump_file, " scalar_type: ");
- print_generic_expr (dump_file, scalar_type, TDF_DETAILS);
- }
- /* It is not possible to vectorize this data reference. */
- return false;
- }
- STMT_VINFO_VECTYPE (stmt_info) = vectype;
- gcc_assert (TREE_CODE (ref) == ARRAY_REF || TREE_CODE (ref) == INDIRECT_REF);
-
- if (TREE_CODE (ref) == ARRAY_REF)
- dr_base = ref;
- else
- dr_base = STMT_VINFO_VECT_DR_BASE (stmt_info);
-
- base = vect_get_base_and_bit_offset (dr, dr_base, vectype,
- loop_vinfo, &bit_offset, &base_aligned_p);
- if (!base)
- {
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "Unknown alignment for access: ");
- print_generic_expr (dump_file,
- STMT_VINFO_VECT_DR_BASE (stmt_info), TDF_SLIM);
- }
- return true;
- }
-
- if (!base_aligned_p)
- {
- if (!vect_can_force_dr_alignment_p (base, TYPE_ALIGN (vectype)))
- {
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "can't force alignment of ref: ");
- print_generic_expr (dump_file, ref, TDF_SLIM);
- }
- return true;
- }
-
- /* Force the alignment of the decl.
- NOTE: This is the only change to the code we make during
- the analysis phase, before deciding to vectorize the loop. */
- if (vect_debug_details (NULL))
- fprintf (dump_file, "force alignment");
- DECL_ALIGN (base) = TYPE_ALIGN (vectype);
- DECL_USER_ALIGN (base) = 1;
- }
-
- /* At this point we assume that the base is aligned, and the offset from it
- (including index, if relevant) has been computed and is in BIT_OFFSET. */
- gcc_assert (base_aligned_p
- || (TREE_CODE (base) == VAR_DECL
- && DECL_ALIGN (base) >= TYPE_ALIGN (vectype)));
-
- /* Convert into bytes. */
- offset = int_const_binop (TRUNC_DIV_EXPR, bit_offset, unit_bits, 1);
- /* Check that there is no remainder in bits. */
- bit_offset = int_const_binop (TRUNC_MOD_EXPR, bit_offset, unit_bits, 1);
- if (!integer_zerop (bit_offset))
- {
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "bit offset alignment: ");
- print_generic_expr (dump_file, bit_offset, TDF_SLIM);
- }
- return false;
- }
-
- /* Alignment required, in bytes: */
- alignment = fold_convert (unsigned_type_node,
- build_int_cst (NULL_TREE, TYPE_ALIGN (vectype)/BITS_PER_UNIT));
-
- /* Modulo alignment. */
- offset = int_const_binop (TRUNC_MOD_EXPR, offset, alignment, 0);
- if (!host_integerp (offset, 1) || TREE_OVERFLOW (offset))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "unexpected misalign value");
- return false;
- }
-
- DR_MISALIGNMENT (dr) = tree_low_cst (offset, 1);
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "misalign = %d", DR_MISALIGNMENT (dr));
-
- return true;
-}
-
-
-/* Function vect_compute_array_ref_alignment
-
- Compute the alignment of an array-ref.
- The alignment we compute here is relative to
- TYPE_ALIGN(VECTYPE) boundary.
-
- Output:
- OFFSET - the alignment in bits
- Return value - the base of the array-ref. E.g,
- if the array-ref is a.b[k].c[i][j] the returned
- base is a.b[k].c
-*/
-
-static tree
-vect_compute_array_ref_alignment (struct data_reference *dr,
- loop_vec_info loop_vinfo,
- tree vectype,
- tree *offset)
-{
- tree array_first_index = size_zero_node;
- tree init;
- tree ref = DR_REF (dr);
- tree scalar_type = TREE_TYPE (ref);
- tree oprnd0 = TREE_OPERAND (ref, 0);
- tree dims = size_one_node;
- tree misalign = size_zero_node;
- tree next_ref, this_offset = size_zero_node;
- tree nunits;
- tree nbits;
-
- if (TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE)
- /* The reference is an array without its last index. */
- next_ref = vect_compute_array_base_alignment (ref, vectype, &dims,
- &misalign);
- else
- next_ref = vect_compute_array_base_alignment (oprnd0, vectype, &dims,
- &misalign);
- if (!vectype)
- /* Alignment is not requested. Just return the base. */
- return next_ref;
-
- /* Compute alignment. */
- if (!host_integerp (misalign, 1) || TREE_OVERFLOW (misalign) || !next_ref)
- return NULL_TREE;
- this_offset = misalign;
-
- /* Check the first index accessed. */
- if (!vect_get_first_index (ref, &array_first_index))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "no first_index for array.");
- return NULL_TREE;
- }
-
- /* Check the index of the array_ref. */
- init = initial_condition_in_loop_num (DR_ACCESS_FN (dr, 0),
- LOOP_VINFO_LOOP (loop_vinfo)->num);
-
- /* FORNOW: In order to simplify the handling of alignment, we make sure
- that the first location at which the array is accessed ('init') is on an
- 'NUNITS' boundary, since we are assuming here that 'array base' is aligned.
- This is too conservative, since we require that
- both {'array_base' is a multiple of NUNITS} && {'init' is a multiple of
- NUNITS}, instead of just {('array_base' + 'init') is a multiple of NUNITS}.
- This should be relaxed in the future. */
-
- if (!init || !host_integerp (init, 0))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "non constant init. ");
- return NULL_TREE;
- }
-
- /* bytes per scalar element: */
- nunits = fold_convert (unsigned_type_node,
- build_int_cst (NULL_TREE, GET_MODE_SIZE (TYPE_MODE (scalar_type))));
- nbits = int_const_binop (MULT_EXPR, nunits,
- build_int_cst (NULL_TREE, BITS_PER_UNIT), 1);
-
- /* misalign = offset + (init-array_first_index)*nunits*bits_in_byte */
- misalign = int_const_binop (MINUS_EXPR, init, array_first_index, 0);
- misalign = int_const_binop (MULT_EXPR, misalign, nbits, 0);
- misalign = int_const_binop (PLUS_EXPR, misalign, this_offset, 0);
-
- /* TODO: allow negative misalign values. */
- if (!host_integerp (misalign, 1) || TREE_OVERFLOW (misalign))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "unexpected misalign value");
- return NULL_TREE;
- }
- *offset = misalign;
- return next_ref;
-}
-
-
-/* Function vect_compute_data_refs_alignment
-
- Compute the misalignment of data references in the loop.
- This pass may take place at function granularity instead of at loop
- granularity.
-
- FOR NOW: No analysis is actually performed. Misalignment is calculated
- only for trivial cases. TODO. */
-
-static bool
-vect_compute_data_refs_alignment (loop_vec_info loop_vinfo)
-{
- varray_type loop_write_datarefs = LOOP_VINFO_DATAREF_WRITES (loop_vinfo);
- varray_type loop_read_datarefs = LOOP_VINFO_DATAREF_READS (loop_vinfo);
- unsigned int i;
-
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_write_datarefs); i++)
- {
- struct data_reference *dr = VARRAY_GENERIC_PTR (loop_write_datarefs, i);
- if (!vect_compute_data_ref_alignment (dr, loop_vinfo))
- return false;
- }
-
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_read_datarefs); i++)
- {
- struct data_reference *dr = VARRAY_GENERIC_PTR (loop_read_datarefs, i);
- if (!vect_compute_data_ref_alignment (dr, loop_vinfo))
- return false;
- }
-
- return true;
-}
-
-
-/* Function vect_enhance_data_refs_alignment
-
- This pass will use loop versioning and loop peeling in order to enhance
- the alignment of data references in the loop.
-
- FOR NOW: we assume that whatever versioning/peeling takes place, only the
- original loop is to be vectorized; Any other loops that are created by
- the transformations performed in this pass - are not supposed to be
- vectorized. This restriction will be relaxed. */
-
-static void
-vect_enhance_data_refs_alignment (loop_vec_info loop_vinfo)
-{
- varray_type loop_read_datarefs = LOOP_VINFO_DATAREF_READS (loop_vinfo);
- varray_type loop_write_datarefs = LOOP_VINFO_DATAREF_WRITES (loop_vinfo);
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- unsigned int i;
-
- /*
- This pass will require a cost model to guide it whether to apply peeling
- or versioning or a combination of the two. For example, the scheme that
- intel uses when given a loop with several memory accesses, is as follows:
- choose one memory access ('p') which alignment you want to force by doing
- peeling. Then, either (1) generate a loop in which 'p' is aligned and all
- other accesses are not necessarily aligned, or (2) use loop versioning to
- generate one loop in which all accesses are aligned, and another loop in
- which only 'p' is necessarily aligned.
-
- ("Automatic Intra-Register Vectorization for the Intel Architecture",
- Aart J.C. Bik, Milind Girkar, Paul M. Grey and Ximmin Tian, International
- Journal of Parallel Programming, Vol. 30, No. 2, April 2002.)
-
- Devising a cost model is the most critical aspect of this work. It will
- guide us on which access to peel for, whether to use loop versioning, how
- many versions to create, etc. The cost model will probably consist of
- generic considerations as well as target specific considerations (on
- powerpc for example, misaligned stores are more painful than misaligned
- loads).
-
- Here is the general steps involved in alignment enhancements:
-
- -- original loop, before alignment analysis:
- for (i=0; i<N; i++){
- x = q[i]; # DR_MISALIGNMENT(q) = unknown
- p[i] = y; # DR_MISALIGNMENT(p) = unknown
- }
-
- -- After vect_compute_data_refs_alignment:
- for (i=0; i<N; i++){
- x = q[i]; # DR_MISALIGNMENT(q) = 3
- p[i] = y; # DR_MISALIGNMENT(p) = unknown
- }
-
- -- Possibility 1: we do loop versioning:
- if (p is aligned) {
- for (i=0; i<N; i++){ # loop 1A
- x = q[i]; # DR_MISALIGNMENT(q) = 3
- p[i] = y; # DR_MISALIGNMENT(p) = 0
- }
- }
- else {
- for (i=0; i<N; i++){ # loop 1B
- x = q[i]; # DR_MISALIGNMENT(q) = 3
- p[i] = y; # DR_MISALIGNMENT(p) = unaligned
- }
- }
-
- -- Possibility 2: we do loop peeling:
- for (i = 0; i < 3; i++){ # (scalar loop, not to be vectorized).
- x = q[i];
- p[i] = y;
- }
- for (i = 3; i < N; i++){ # loop 2A
- x = q[i]; # DR_MISALIGNMENT(q) = 0
- p[i] = y; # DR_MISALIGNMENT(p) = unknown
- }
-
- -- Possibility 3: combination of loop peeling and versioning:
- for (i = 0; i < 3; i++){ # (scalar loop, not to be vectorized).
- x = q[i];
- p[i] = y;
- }
- if (p is aligned) {
- for (i = 3; i<N; i++){ # loop 3A
- x = q[i]; # DR_MISALIGNMENT(q) = 0
- p[i] = y; # DR_MISALIGNMENT(p) = 0
- }
- }
- else {
- for (i = 3; i<N; i++){ # loop 3B
- x = q[i]; # DR_MISALIGNMENT(q) = 0
- p[i] = y; # DR_MISALIGNMENT(p) = unaligned
- }
- }
-
- These loops are later passed to loop_transform to be vectorized. The
- vectorizer will use the alignment information to guide the transformation
- (whether to generate regular loads/stores, or with special handling for
- misalignment).
- */
-
- /* (1) Peeling to force alignment. */
-
- /* (1.1) Decide whether to perform peeling, and how many iterations to peel:
- Considerations:
- + How many accesses will become aligned due to the peeling
- - How many accesses will become unaligned due to the peeling,
- and the cost of misaligned accesses.
- - The cost of peeling (the extra runtime checks, the increase
- in code size).
-
- The scheme we use FORNOW: peel to force the alignment of the first
- misaligned store in the loop.
- Rationale: misaligned stores are not yet supported.
-
- TODO: Use a better cost model. */
-
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_write_datarefs); i++)
- {
- struct data_reference *dr = VARRAY_GENERIC_PTR (loop_write_datarefs, i);
- if (!aligned_access_p (dr))
- {
- LOOP_VINFO_UNALIGNED_DR (loop_vinfo) = dr;
- LOOP_DO_PEELING_FOR_ALIGNMENT (loop_vinfo) = true;
- break;
- }
- }
-
- if (!LOOP_VINFO_UNALIGNED_DR (loop_vinfo))
- {
- if (vect_debug_details (loop))
- fprintf (dump_file, "Peeling for alignment will not be applied.");
- return;
- }
- else
- if (vect_debug_details (loop))
- fprintf (dump_file, "Peeling for alignment will be applied.");
-
-
- /* (1.2) Update the alignment info according to the peeling factor.
- If the misalignment of the DR we peel for is M, then the
- peeling factor is VF - M, and the misalignment of each access DR_i
- in the loop is DR_MISALIGNMENT (DR_i) + VF - M.
- If the misalignment of the DR we peel for is unknown, then the
- misalignment of each access DR_i in the loop is also unknown.
-
- FORNOW: set the misalignment of the accesses to unknown even
- if the peeling factor is known at compile time.
-
- TODO: - if the peeling factor is known at compile time, use that
- when updating the misalignment info of the loop DRs.
- - consider accesses that are known to have the same
- alignment, even if that alignment is unknown. */
-
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_write_datarefs); i++)
- {
- struct data_reference *dr = VARRAY_GENERIC_PTR (loop_write_datarefs, i);
- if (dr == LOOP_VINFO_UNALIGNED_DR (loop_vinfo))
- DR_MISALIGNMENT (dr) = 0;
- else
- DR_MISALIGNMENT (dr) = -1;
- }
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_read_datarefs); i++)
- {
- struct data_reference *dr = VARRAY_GENERIC_PTR (loop_read_datarefs, i);
- if (dr == LOOP_VINFO_UNALIGNED_DR (loop_vinfo))
- DR_MISALIGNMENT (dr) = 0;
- else
- DR_MISALIGNMENT (dr) = -1;
- }
-}
-
-
-/* Function vect_analyze_data_refs_alignment
-
- Analyze the alignment of the data-references in the loop.
- FOR NOW: Until support for misliagned accesses is in place, only if all
- accesses are aligned can the loop be vectorized. This restriction will be
- relaxed. */
-
-static bool
-vect_analyze_data_refs_alignment (loop_vec_info loop_vinfo)
-{
- varray_type loop_read_datarefs = LOOP_VINFO_DATAREF_READS (loop_vinfo);
- varray_type loop_write_datarefs = LOOP_VINFO_DATAREF_WRITES (loop_vinfo);
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- enum dr_alignment_support supportable_dr_alignment;
- unsigned int i;
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "\n<<vect_analyze_data_refs_alignment>>\n");
-
-
- /* This pass may take place at function granularity instead of at loop
- granularity. */
-
- if (!vect_compute_data_refs_alignment (loop_vinfo))
- {
- if (vect_debug_details (loop) || vect_debug_stats (loop))
- fprintf (dump_file,
- "not vectorized: can't calculate alignment for data ref.");
- return false;
- }
-
-
- /* This pass will decide on using loop versioning and/or loop peeling in
- order to enhance the alignment of data references in the loop. */
-
- vect_enhance_data_refs_alignment (loop_vinfo);
-
-
- /* Finally, check that all the data references in the loop can be
- handled with respect to their alignment. */
-
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_read_datarefs); i++)
- {
- struct data_reference *dr = VARRAY_GENERIC_PTR (loop_read_datarefs, i);
- supportable_dr_alignment = vect_supportable_dr_alignment (dr);
- if (!supportable_dr_alignment)
- {
- if (vect_debug_details (loop) || vect_debug_stats (loop))
- fprintf (dump_file, "not vectorized: unsupported unaligned load.");
- return false;
- }
- }
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_write_datarefs); i++)
- {
- struct data_reference *dr = VARRAY_GENERIC_PTR (loop_write_datarefs, i);
- supportable_dr_alignment = vect_supportable_dr_alignment (dr);
- if (!supportable_dr_alignment)
- {
- if (vect_debug_details (loop) || vect_debug_stats (loop))
- fprintf (dump_file, "not vectorized: unsupported unaligned store.");
- return false;
- }
- }
-
- return true;
-}
-
-
-/* Function vect_analyze_data_ref_access.
-
- Analyze the access pattern of the data-reference DR. For now, a data access
- has to consecutive and aligned to be considered vectorizable. */
-
-static bool
-vect_analyze_data_ref_access (struct data_reference *dr)
-{
- varray_type access_fns = DR_ACCESS_FNS (dr);
- tree access_fn;
- tree init, step;
- unsigned int dimensions, i;
-
- /* Check that in case of multidimensional array ref A[i1][i2]..[iN],
- i1, i2, ..., iN-1 are loop invariant (to make sure that the memory
- access is contiguous). */
- dimensions = VARRAY_ACTIVE_SIZE (access_fns);
-
- for (i = 1; i < dimensions; i++) /* Not including the last dimension. */
- {
- access_fn = DR_ACCESS_FN (dr, i);
-
- if (evolution_part_in_loop_num (access_fn,
- loop_containing_stmt (DR_STMT (dr))->num))
- {
- /* Evolution part is not NULL in this loop (it is neither constant
- nor invariant). */
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file,
- "not vectorized: complicated multidim. array access.");
- print_generic_expr (dump_file, access_fn, TDF_SLIM);
- }
- return false;
- }
- }
-
- access_fn = DR_ACCESS_FN (dr, 0); /* The last dimension access function. */
- if (!evolution_function_is_constant_p (access_fn)
- && !vect_is_simple_iv_evolution (loop_containing_stmt (DR_STMT (dr))->num,
- access_fn, &init, &step, true))
- {
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "not vectorized: complicated access function.");
- print_generic_expr (dump_file, access_fn, TDF_SLIM);
- }
- return false;
- }
-
- return true;
-}
-
-
-/* Function vect_analyze_data_ref_accesses.
-
- Analyze the access pattern of all the data references in the loop.
-
- FORNOW: the only access pattern that is considered vectorizable is a
- simple step 1 (consecutive) access.
-
- FORNOW: handle only arrays and pointer accesses. */
-
-static bool
-vect_analyze_data_ref_accesses (loop_vec_info loop_vinfo)
-{
- unsigned int i;
- varray_type loop_write_datarefs = LOOP_VINFO_DATAREF_WRITES (loop_vinfo);
- varray_type loop_read_datarefs = LOOP_VINFO_DATAREF_READS (loop_vinfo);
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "\n<<vect_analyze_data_ref_accesses>>\n");
-
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_write_datarefs); i++)
- {
- struct data_reference *dr = VARRAY_GENERIC_PTR (loop_write_datarefs, i);
- bool ok = vect_analyze_data_ref_access (dr);
- if (!ok)
- {
- if (vect_debug_stats (LOOP_VINFO_LOOP (loop_vinfo))
- || vect_debug_details (LOOP_VINFO_LOOP (loop_vinfo)))
- fprintf (dump_file, "not vectorized: complicated access pattern.");
- return false;
- }
- }
-
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_read_datarefs); i++)
- {
- struct data_reference *dr = VARRAY_GENERIC_PTR (loop_read_datarefs, i);
- bool ok = vect_analyze_data_ref_access (dr);
- if (!ok)
- {
- if (vect_debug_stats (LOOP_VINFO_LOOP (loop_vinfo))
- || vect_debug_details (LOOP_VINFO_LOOP (loop_vinfo)))
- fprintf (dump_file, "not vectorized: complicated access pattern.");
- return false;
- }
- }
-
- return true;
-}
-
-
-/* Function vect_analyze_pointer_ref_access.
-
- Input:
- STMT - a stmt that contains a data-ref
- MEMREF - a data-ref in STMT, which is an INDIRECT_REF.
-
- If the data-ref access is vectorizable, return a data_reference structure
- that represents it (DR). Otherwise - return NULL. */
-
-static struct data_reference *
-vect_analyze_pointer_ref_access (tree memref, tree stmt, bool is_read)
-{
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- struct loop *loop = STMT_VINFO_LOOP (stmt_info);
- tree access_fn = analyze_scalar_evolution (loop, TREE_OPERAND (memref, 0));
- tree init, step;
- int step_val;
- tree reftype, innertype;
- enum machine_mode innermode;
- tree indx_access_fn;
- int loopnum = loop->num;
- struct data_reference *dr;
-
- if (!access_fn)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: complicated pointer access.");
- return NULL;
- }
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "Access function of ptr: ");
- print_generic_expr (dump_file, access_fn, TDF_SLIM);
- }
-
- if (!vect_is_simple_iv_evolution (loopnum, access_fn, &init, &step, false))
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: pointer access is not simple.");
- return NULL;
- }
-
- STRIP_NOPS (init);
-
- if (!host_integerp (step,0))
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file,
- "not vectorized: non constant step for pointer access.");
- return NULL;
- }
-
- step_val = TREE_INT_CST_LOW (step);
-
- reftype = TREE_TYPE (TREE_OPERAND (memref, 0));
- if (TREE_CODE (reftype) != POINTER_TYPE)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: unexpected pointer access form.");
- return NULL;
- }
-
- reftype = TREE_TYPE (init);
- if (TREE_CODE (reftype) != POINTER_TYPE)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: unexpected pointer access form.");
- return NULL;
- }
-
- innertype = TREE_TYPE (reftype);
- innermode = TYPE_MODE (innertype);
- if (GET_MODE_SIZE (innermode) != step_val)
- {
- /* FORNOW: support only consecutive access */
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: non consecutive access.");
- return NULL;
- }
-
- indx_access_fn =
- build_polynomial_chrec (loopnum, integer_zero_node, integer_one_node);
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "Access function of ptr indx: ");
- print_generic_expr (dump_file, indx_access_fn, TDF_SLIM);
- }
- dr = init_data_ref (stmt, memref, init, indx_access_fn, is_read);
- return dr;
-}
-
-
-/* Function vect_get_symbl_and_dr.
-
- The function returns SYMBL - the relevant variable for
- memory tag (for aliasing purposes).
- Also data reference structure DR is created.
-
- Input:
- MEMREF - data reference in STMT
- IS_READ - TRUE if STMT reads from MEMREF, FALSE if writes to MEMREF
-
- Output:
- DR - data_reference struct for MEMREF
- return value - the relevant variable for memory tag (for aliasing purposes).
-
-*/
-
-static tree
-vect_get_symbl_and_dr (tree memref, tree stmt, bool is_read,
- loop_vec_info loop_vinfo, struct data_reference **dr)
-{
- tree symbl, oprnd0, oprnd1;
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- tree offset;
- tree array_base, base;
- struct data_reference *new_dr;
- bool base_aligned_p;
-
- *dr = NULL;
- switch (TREE_CODE (memref))
- {
- case INDIRECT_REF:
- new_dr = vect_analyze_pointer_ref_access (memref, stmt, is_read);
- if (! new_dr)
- return NULL_TREE;
- *dr = new_dr;
- symbl = DR_BASE_NAME (new_dr);
- STMT_VINFO_VECT_DR_BASE (stmt_info) = symbl;
-
- switch (TREE_CODE (symbl))
- {
- case PLUS_EXPR:
- case MINUS_EXPR:
- oprnd0 = TREE_OPERAND (symbl, 0);
- oprnd1 = TREE_OPERAND (symbl, 1);
-
- STRIP_NOPS(oprnd1);
- /* Only {address_base + offset} expressions are supported,
- where address_base can be POINTER_TYPE or ARRAY_TYPE and
- offset can be anything but POINTER_TYPE or ARRAY_TYPE.
- TODO: swap operands if {offset + address_base}. */
- if ((TREE_CODE (TREE_TYPE (oprnd1)) == POINTER_TYPE
- && TREE_CODE (oprnd1) != INTEGER_CST)
- || TREE_CODE (TREE_TYPE (oprnd1)) == ARRAY_TYPE)
- return NULL_TREE;
-
- if (TREE_CODE (TREE_TYPE (oprnd0)) == POINTER_TYPE)
- symbl = oprnd0;
- else
- symbl = vect_get_symbl_and_dr (oprnd0, stmt, is_read,
- loop_vinfo, &new_dr);
-
- case SSA_NAME:
- case ADDR_EXPR:
- /* symbl remains unchanged. */
- break;
-
- default:
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "unhandled data ref: ");
- print_generic_expr (dump_file, memref, TDF_SLIM);
- fprintf (dump_file, " (symbl ");
- print_generic_expr (dump_file, symbl, TDF_SLIM);
- fprintf (dump_file, ") in stmt ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
- return NULL_TREE;
- }
- break;
-
- case ARRAY_REF:
- offset = size_zero_node;
-
- /* Store the array base in the stmt info.
- For one dimensional array ref a[i], the base is a,
- for multidimensional a[i1][i2]..[iN], the base is
- a[i1][i2]..[iN-1]. */
- array_base = TREE_OPERAND (memref, 0);
- STMT_VINFO_VECT_DR_BASE (stmt_info) = array_base;
-
- new_dr = analyze_array (stmt, memref, is_read);
- *dr = new_dr;
-
- /* Find the relevant symbol for aliasing purposes. */
- base = DR_BASE_NAME (new_dr);
- switch (TREE_CODE (base))
- {
- case VAR_DECL:
- symbl = base;
- break;
-
- case INDIRECT_REF:
- symbl = TREE_OPERAND (base, 0);
- break;
-
- case COMPONENT_REF:
- /* Could have recorded more accurate information -
- i.e, the actual FIELD_DECL that is being referenced -
- but later passes expect VAR_DECL as the nmt. */
- symbl = vect_get_base_and_bit_offset (new_dr, base, NULL_TREE,
- loop_vinfo, &offset, &base_aligned_p);
- if (symbl)
- break;
- /* fall through */
- default:
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "unhandled struct/class field access ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
- return NULL_TREE;
- }
- break;
-
- default:
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "unhandled data ref: ");
- print_generic_expr (dump_file, memref, TDF_SLIM);
- fprintf (dump_file, " in stmt ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
- return NULL_TREE;
- }
- return symbl;
-}
-
-
-/* Function vect_analyze_data_refs.
-
- Find all the data references in the loop.
-
- FORNOW: Handle aligned INDIRECT_REFs and ARRAY_REFs
- which base is really an array (not a pointer) and which alignment
- can be forced. This restriction will be relaxed. */
-
-static bool
-vect_analyze_data_refs (loop_vec_info loop_vinfo)
-{
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- basic_block *bbs = LOOP_VINFO_BBS (loop_vinfo);
- int nbbs = loop->num_nodes;
- block_stmt_iterator si;
- int j;
- struct data_reference *dr;
- tree tag;
- tree address_base;
- bool base_aligned_p;
- tree offset;
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "\n<<vect_analyze_data_refs>>\n");
-
- for (j = 0; j < nbbs; j++)
- {
- basic_block bb = bbs[j];
- for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
- {
- bool is_read = false;
- tree stmt = bsi_stmt (si);
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- v_may_def_optype v_may_defs = STMT_V_MAY_DEF_OPS (stmt);
- v_must_def_optype v_must_defs = STMT_V_MUST_DEF_OPS (stmt);
- vuse_optype vuses = STMT_VUSE_OPS (stmt);
- varray_type *datarefs = NULL;
- int nvuses, nv_may_defs, nv_must_defs;
- tree memref = NULL;
- tree symbl;
-
- /* Assumption: there exists a data-ref in stmt, if and only if
- it has vuses/vdefs. */
-
- if (!vuses && !v_may_defs && !v_must_defs)
- continue;
-
- nvuses = NUM_VUSES (vuses);
- nv_may_defs = NUM_V_MAY_DEFS (v_may_defs);
- nv_must_defs = NUM_V_MUST_DEFS (v_must_defs);
-
- if (nvuses && (nv_may_defs || nv_must_defs))
- {
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "unexpected vdefs and vuses in stmt: ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
- return false;
- }
-
- if (TREE_CODE (stmt) != MODIFY_EXPR)
- {
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "unexpected vops in stmt: ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
- return false;
- }
-
- if (vuses)
- {
- memref = TREE_OPERAND (stmt, 1);
- datarefs = &(LOOP_VINFO_DATAREF_READS (loop_vinfo));
- is_read = true;
- }
- else /* vdefs */
- {
- memref = TREE_OPERAND (stmt, 0);
- datarefs = &(LOOP_VINFO_DATAREF_WRITES (loop_vinfo));
- is_read = false;
- }
-
- /* Analyze MEMREF. If it is of a supported form, build data_reference
- struct for it (DR) and find the relevant symbol for aliasing
- purposes. */
- symbl = vect_get_symbl_and_dr (memref, stmt, is_read, loop_vinfo,
- &dr);
- if (!symbl)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- {
- fprintf (dump_file, "not vectorized: unhandled data ref: ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
- return false;
- }
-
- /* Find and record the memtag assigned to this data-ref. */
- switch (TREE_CODE (symbl))
- {
- case VAR_DECL:
- STMT_VINFO_MEMTAG (stmt_info) = symbl;
- break;
-
- case SSA_NAME:
- symbl = SSA_NAME_VAR (symbl);
- tag = get_var_ann (symbl)->type_mem_tag;
- if (!tag)
- {
- tree ptr = TREE_OPERAND (memref, 0);
- if (TREE_CODE (ptr) == SSA_NAME)
- tag = get_var_ann (SSA_NAME_VAR (ptr))->type_mem_tag;
- }
- if (!tag)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: no memtag for ref.");
- return false;
- }
- STMT_VINFO_MEMTAG (stmt_info) = tag;
- break;
-
- case ADDR_EXPR:
- address_base = TREE_OPERAND (symbl, 0);
-
- switch (TREE_CODE (address_base))
- {
- case ARRAY_REF:
- {
- struct data_reference *tmp_dr;
-
- tmp_dr = analyze_array (stmt, TREE_OPERAND (symbl, 0),
- DR_IS_READ (dr));
- tag = vect_get_base_and_bit_offset
- (tmp_dr, DR_BASE_NAME (tmp_dr),
- NULL_TREE, loop_vinfo, &offset, &base_aligned_p);
- if (!tag)
- {
- if (vect_debug_stats (loop)
- || vect_debug_details (loop))
- fprintf (dump_file,
- "not vectorized: no memtag for ref.");
- return false;
- }
- STMT_VINFO_MEMTAG (stmt_info) = tag;
- }
-
- break;
-
- case VAR_DECL:
- STMT_VINFO_MEMTAG (stmt_info) = address_base;
- break;
-
- default:
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- {
- fprintf (dump_file,
- "not vectorized: unhandled address expr: ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
- return false;
- }
- break;
-
- default:
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- {
- fprintf (dump_file, "not vectorized: unsupported data-ref: ");
- print_generic_expr (dump_file, memref, TDF_SLIM);
- }
- return false;
- }
-
- VARRAY_PUSH_GENERIC_PTR (*datarefs, dr);
- STMT_VINFO_DATA_REF (stmt_info) = dr;
- }
- }
-
- return true;
-}
-
-
-/* Utility functions used by vect_mark_stmts_to_be_vectorized. */
-
-/* Function vect_mark_relevant.
-
- Mark STMT as "relevant for vectorization" and add it to WORKLIST. */
-
-static void
-vect_mark_relevant (varray_type worklist, tree stmt)
-{
- stmt_vec_info stmt_info;
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "mark relevant.");
-
- if (TREE_CODE (stmt) == PHI_NODE)
- {
- VARRAY_PUSH_TREE (worklist, stmt);
- return;
- }
-
- stmt_info = vinfo_for_stmt (stmt);
-
- if (!stmt_info)
- {
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "mark relevant: no stmt info!!.");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
- return;
- }
-
- if (STMT_VINFO_RELEVANT_P (stmt_info))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "already marked relevant.");
- return;
- }
-
- STMT_VINFO_RELEVANT_P (stmt_info) = 1;
- VARRAY_PUSH_TREE (worklist, stmt);
-}
-
-
-/* Function vect_stmt_relevant_p.
-
- Return true if STMT in loop that is represented by LOOP_VINFO is
- "relevant for vectorization".
-
- A stmt is considered "relevant for vectorization" if:
- - it has uses outside the loop.
- - it has vdefs (it alters memory).
- - control stmts in the loop (except for the exit condition).
-
- CHECKME: what other side effects would the vectorizer allow? */
-
-static bool
-vect_stmt_relevant_p (tree stmt, loop_vec_info loop_vinfo)
-{
- v_may_def_optype v_may_defs;
- v_must_def_optype v_must_defs;
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- int i;
- dataflow_t df;
- int num_uses;
-
- /* cond stmt other than loop exit cond. */
- if (is_ctrl_stmt (stmt) && (stmt != LOOP_VINFO_EXIT_COND (loop_vinfo)))
- return true;
-
- /* changing memory. */
- v_may_defs = STMT_V_MAY_DEF_OPS (stmt);
- v_must_defs = STMT_V_MUST_DEF_OPS (stmt);
- if (v_may_defs || v_must_defs)
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "vec_stmt_relevant_p: stmt has vdefs.");
- return true;
- }
-
- /* uses outside the loop. */
- df = get_immediate_uses (stmt);
- num_uses = num_immediate_uses (df);
- for (i = 0; i < num_uses; i++)
- {
- tree use = immediate_use (df, i);
- basic_block bb = bb_for_stmt (use);
- if (!flow_bb_inside_loop_p (loop, bb))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "vec_stmt_relevant_p: used out of loop.");
- return true;
- }
- }
-
- return false;
-}
-
-
-/* Function vect_mark_stmts_to_be_vectorized.
-
- Not all stmts in the loop need to be vectorized. For example:
-
- for i...
- for j...
- 1. T0 = i + j
- 2. T1 = a[T0]
-
- 3. j = j + 1
-
- Stmt 1 and 3 do not need to be vectorized, because loop control and
- addressing of vectorized data-refs are handled differently.
-
- This pass detects such stmts. */
-
-static bool
-vect_mark_stmts_to_be_vectorized (loop_vec_info loop_vinfo)
-{
- varray_type worklist;
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- basic_block *bbs = LOOP_VINFO_BBS (loop_vinfo);
- unsigned int nbbs = loop->num_nodes;
- block_stmt_iterator si;
- tree stmt;
- stmt_ann_t ann;
- unsigned int i;
- int j;
- use_optype use_ops;
- stmt_vec_info stmt_info;
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "\n<<vect_mark_stmts_to_be_vectorized>>\n");
-
- VARRAY_TREE_INIT (worklist, 64, "work list");
-
- /* 1. Init worklist. */
-
- for (i = 0; i < nbbs; i++)
- {
- basic_block bb = bbs[i];
- for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
- {
- stmt = bsi_stmt (si);
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "init: stmt relevant? ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
-
- stmt_info = vinfo_for_stmt (stmt);
- STMT_VINFO_RELEVANT_P (stmt_info) = 0;
-
- if (vect_stmt_relevant_p (stmt, loop_vinfo))
- vect_mark_relevant (worklist, stmt);
- }
- }
-
-
- /* 2. Process_worklist */
-
- while (VARRAY_ACTIVE_SIZE (worklist) > 0)
- {
- stmt = VARRAY_TOP_TREE (worklist);
- VARRAY_POP (worklist);
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "worklist: examine stmt: ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
-
- /* Examine the USES in this statement. Mark all the statements which
- feed this statement's uses as "relevant", unless the USE is used as
- an array index. */
-
- if (TREE_CODE (stmt) == PHI_NODE)
- {
- /* follow the def-use chain inside the loop. */
- for (j = 0; j < PHI_NUM_ARGS (stmt); j++)
- {
- tree arg = PHI_ARG_DEF (stmt, j);
- tree def_stmt = NULL_TREE;
- basic_block bb;
- if (!vect_is_simple_use (arg, loop, &def_stmt))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "worklist: unsupported use.");
- varray_clear (worklist);
- return false;
- }
- if (!def_stmt)
- continue;
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "worklist: def_stmt: ");
- print_generic_expr (dump_file, def_stmt, TDF_SLIM);
- }
-
- bb = bb_for_stmt (def_stmt);
- if (flow_bb_inside_loop_p (loop, bb))
- vect_mark_relevant (worklist, def_stmt);
- }
- }
-
- ann = stmt_ann (stmt);
- use_ops = USE_OPS (ann);
-
- for (i = 0; i < NUM_USES (use_ops); i++)
- {
- tree use = USE_OP (use_ops, i);
-
- /* We are only interested in uses that need to be vectorized. Uses
- that are used for address computation are not considered relevant.
- */
- if (exist_non_indexing_operands_for_use_p (use, stmt))
- {
- tree def_stmt = NULL_TREE;
- basic_block bb;
- if (!vect_is_simple_use (use, loop, &def_stmt))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "worklist: unsupported use.");
- varray_clear (worklist);
- return false;
- }
-
- if (!def_stmt)
- continue;
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "worklist: examine use %d: ", i);
- print_generic_expr (dump_file, use, TDF_SLIM);
- }
-
- bb = bb_for_stmt (def_stmt);
- if (flow_bb_inside_loop_p (loop, bb))
- vect_mark_relevant (worklist, def_stmt);
- }
- }
- } /* while worklist */
-
- varray_clear (worklist);
- return true;
-}
-
-
-/* Function vect_can_advance_ivs_p
-
- In case the number of iterations that LOOP iterates in unknown at compile
- time, an epilog loop will be generated, and the loop induction variables
- (IVs) will be "advanced" to the value they are supposed to take just before
- the epilog loop. Here we check that the access function of the loop IVs
- and the expression that represents the loop bound are simple enough.
- These restrictions will be relaxed in the future. */
-
-static bool
-vect_can_advance_ivs_p (struct loop *loop)
-{
- basic_block bb = loop->header;
- tree phi;
-
- /* Analyze phi functions of the loop header. */
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