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Diffstat (limited to 'gcc/tree-dfa.cc')
| -rw-r--r-- | gcc/tree-dfa.cc | 1048 |
1 files changed, 1048 insertions, 0 deletions
diff --git a/gcc/tree-dfa.cc b/gcc/tree-dfa.cc new file mode 100644 index 0000000..21c82ce --- /dev/null +++ b/gcc/tree-dfa.cc @@ -0,0 +1,1048 @@ +/* Data flow functions for trees. + Copyright (C) 2001-2022 Free Software Foundation, Inc. + Contributed by Diego Novillo <dnovillo@redhat.com> + +This file is part of GCC. + +GCC is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 3, or (at your option) +any later version. + +GCC is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +You should have received a copy of the GNU General Public License +along with GCC; see the file COPYING3. If not see +<http://www.gnu.org/licenses/>. */ + +#include "config.h" +#include "system.h" +#include "coretypes.h" +#include "backend.h" +#include "rtl.h" +#include "tree.h" +#include "gimple.h" +#include "tree-pass.h" +#include "ssa.h" +#include "tree-pretty-print.h" +#include "fold-const.h" +#include "stor-layout.h" +#include "langhooks.h" +#include "gimple-iterator.h" +#include "gimple-walk.h" +#include "tree-dfa.h" +#include "gimple-range.h" + +/* Build and maintain data flow information for trees. */ + +/* Counters used to display DFA and SSA statistics. */ +struct dfa_stats_d +{ + long num_defs; + long num_uses; + long num_phis; + long num_phi_args; + size_t max_num_phi_args; + long num_vdefs; + long num_vuses; +}; + + +/* Local functions. */ +static void collect_dfa_stats (struct dfa_stats_d *); + + +/*--------------------------------------------------------------------------- + Dataflow analysis (DFA) routines +---------------------------------------------------------------------------*/ + +/* Renumber all of the gimple stmt uids. */ + +void +renumber_gimple_stmt_uids (struct function *fun) +{ + basic_block bb; + + set_gimple_stmt_max_uid (fun, 0); + FOR_ALL_BB_FN (bb, fun) + { + gimple_stmt_iterator bsi; + for (bsi = gsi_start_phis (bb); !gsi_end_p (bsi); gsi_next (&bsi)) + { + gimple *stmt = gsi_stmt (bsi); + gimple_set_uid (stmt, inc_gimple_stmt_max_uid (fun)); + } + for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) + { + gimple *stmt = gsi_stmt (bsi); + gimple_set_uid (stmt, inc_gimple_stmt_max_uid (fun)); + } + } +} + +/* Like renumber_gimple_stmt_uids, but only do work on the basic blocks + in BLOCKS, of which there are N_BLOCKS. Also renumbers PHIs. */ + +void +renumber_gimple_stmt_uids_in_blocks (basic_block *blocks, int n_blocks) +{ + int i; + + set_gimple_stmt_max_uid (cfun, 0); + for (i = 0; i < n_blocks; i++) + { + basic_block bb = blocks[i]; + gimple_stmt_iterator bsi; + for (bsi = gsi_start_phis (bb); !gsi_end_p (bsi); gsi_next (&bsi)) + { + gimple *stmt = gsi_stmt (bsi); + gimple_set_uid (stmt, inc_gimple_stmt_max_uid (cfun)); + } + for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) + { + gimple *stmt = gsi_stmt (bsi); + gimple_set_uid (stmt, inc_gimple_stmt_max_uid (cfun)); + } + } +} + + + +/*--------------------------------------------------------------------------- + Debugging functions +---------------------------------------------------------------------------*/ + +/* Dump variable VAR and its may-aliases to FILE. */ + +void +dump_variable (FILE *file, tree var) +{ + if (TREE_CODE (var) == SSA_NAME) + { + if (POINTER_TYPE_P (TREE_TYPE (var))) + dump_points_to_info_for (file, var); + var = SSA_NAME_VAR (var); + } + + if (var == NULL_TREE) + { + fprintf (file, "<nil>"); + return; + } + + print_generic_expr (file, var, dump_flags); + + fprintf (file, ", UID D.%u", (unsigned) DECL_UID (var)); + if (DECL_PT_UID (var) != DECL_UID (var)) + fprintf (file, ", PT-UID D.%u", (unsigned) DECL_PT_UID (var)); + + fprintf (file, ", "); + print_generic_expr (file, TREE_TYPE (var), dump_flags); + + if (TREE_ADDRESSABLE (var)) + fprintf (file, ", is addressable"); + + if (is_global_var (var)) + fprintf (file, ", is global"); + + if (TREE_THIS_VOLATILE (var)) + fprintf (file, ", is volatile"); + + if (cfun && ssa_default_def (cfun, var)) + { + fprintf (file, ", default def: "); + print_generic_expr (file, ssa_default_def (cfun, var), dump_flags); + } + + if (DECL_INITIAL (var)) + { + fprintf (file, ", initial: "); + print_generic_expr (file, DECL_INITIAL (var), dump_flags); + } + + fprintf (file, "\n"); +} + + +/* Dump variable VAR and its may-aliases to stderr. */ + +DEBUG_FUNCTION void +debug_variable (tree var) +{ + dump_variable (stderr, var); +} + + +/* Dump various DFA statistics to FILE. */ + +void +dump_dfa_stats (FILE *file) +{ + struct dfa_stats_d dfa_stats; + + unsigned long size, total = 0; + const char * const fmt_str = "%-30s%-13s%12s\n"; + const char * const fmt_str_1 = "%-30s%13lu" PRsa (11) "\n"; + const char * const fmt_str_3 = "%-43s" PRsa (11) "\n"; + const char *funcname + = lang_hooks.decl_printable_name (current_function_decl, 2); + + collect_dfa_stats (&dfa_stats); + + fprintf (file, "\nDFA Statistics for %s\n\n", funcname); + + fprintf (file, "---------------------------------------------------------\n"); + fprintf (file, fmt_str, "", " Number of ", "Memory"); + fprintf (file, fmt_str, "", " instances ", "used "); + fprintf (file, "---------------------------------------------------------\n"); + + size = dfa_stats.num_uses * sizeof (tree *); + total += size; + fprintf (file, fmt_str_1, "USE operands", dfa_stats.num_uses, + SIZE_AMOUNT (size)); + + size = dfa_stats.num_defs * sizeof (tree *); + total += size; + fprintf (file, fmt_str_1, "DEF operands", dfa_stats.num_defs, + SIZE_AMOUNT (size)); + + size = dfa_stats.num_vuses * sizeof (tree *); + total += size; + fprintf (file, fmt_str_1, "VUSE operands", dfa_stats.num_vuses, + SIZE_AMOUNT (size)); + + size = dfa_stats.num_vdefs * sizeof (tree *); + total += size; + fprintf (file, fmt_str_1, "VDEF operands", dfa_stats.num_vdefs, + SIZE_AMOUNT (size)); + + size = dfa_stats.num_phis * sizeof (struct gphi); + total += size; + fprintf (file, fmt_str_1, "PHI nodes", dfa_stats.num_phis, + SIZE_AMOUNT (size)); + + size = dfa_stats.num_phi_args * sizeof (struct phi_arg_d); + total += size; + fprintf (file, fmt_str_1, "PHI arguments", dfa_stats.num_phi_args, + SIZE_AMOUNT (size)); + + fprintf (file, "---------------------------------------------------------\n"); + fprintf (file, fmt_str_3, "Total memory used by DFA/SSA data", + SIZE_AMOUNT (total)); + fprintf (file, "---------------------------------------------------------\n"); + fprintf (file, "\n"); + + if (dfa_stats.num_phis) + fprintf (file, "Average number of arguments per PHI node: %.1f (max: %ld)\n", + (float) dfa_stats.num_phi_args / (float) dfa_stats.num_phis, + (long) dfa_stats.max_num_phi_args); + + fprintf (file, "\n"); +} + + +/* Dump DFA statistics on stderr. */ + +DEBUG_FUNCTION void +debug_dfa_stats (void) +{ + dump_dfa_stats (stderr); +} + + +/* Collect DFA statistics and store them in the structure pointed to by + DFA_STATS_P. */ + +static void +collect_dfa_stats (struct dfa_stats_d *dfa_stats_p ATTRIBUTE_UNUSED) +{ + basic_block bb; + + gcc_assert (dfa_stats_p); + + memset ((void *)dfa_stats_p, 0, sizeof (struct dfa_stats_d)); + + /* Walk all the statements in the function counting references. */ + FOR_EACH_BB_FN (bb, cfun) + { + for (gphi_iterator si = gsi_start_phis (bb); !gsi_end_p (si); + gsi_next (&si)) + { + gphi *phi = si.phi (); + dfa_stats_p->num_phis++; + dfa_stats_p->num_phi_args += gimple_phi_num_args (phi); + if (gimple_phi_num_args (phi) > dfa_stats_p->max_num_phi_args) + dfa_stats_p->max_num_phi_args = gimple_phi_num_args (phi); + } + + for (gimple_stmt_iterator si = gsi_start_bb (bb); !gsi_end_p (si); + gsi_next (&si)) + { + gimple *stmt = gsi_stmt (si); + dfa_stats_p->num_defs += NUM_SSA_OPERANDS (stmt, SSA_OP_DEF); + dfa_stats_p->num_uses += NUM_SSA_OPERANDS (stmt, SSA_OP_USE); + dfa_stats_p->num_vdefs += gimple_vdef (stmt) ? 1 : 0; + dfa_stats_p->num_vuses += gimple_vuse (stmt) ? 1 : 0; + } + } +} + + +/*--------------------------------------------------------------------------- + Miscellaneous helpers +---------------------------------------------------------------------------*/ + +/* Lookup VAR UID in the default_defs hashtable and return the associated + variable. */ + +tree +ssa_default_def (struct function *fn, tree var) +{ + struct tree_decl_minimal ind; + struct tree_ssa_name in; + gcc_assert (VAR_P (var) + || TREE_CODE (var) == PARM_DECL + || TREE_CODE (var) == RESULT_DECL); + + /* Always NULL_TREE for rtl function dumps. */ + if (!fn->gimple_df) + return NULL_TREE; + + in.var = (tree)&ind; + ind.uid = DECL_UID (var); + return DEFAULT_DEFS (fn)->find_with_hash ((tree)&in, DECL_UID (var)); +} + +/* Insert the pair VAR's UID, DEF into the default_defs hashtable + of function FN. */ + +void +set_ssa_default_def (struct function *fn, tree var, tree def) +{ + struct tree_decl_minimal ind; + struct tree_ssa_name in; + + gcc_assert (VAR_P (var) + || TREE_CODE (var) == PARM_DECL + || TREE_CODE (var) == RESULT_DECL); + in.var = (tree)&ind; + ind.uid = DECL_UID (var); + if (!def) + { + tree *loc = DEFAULT_DEFS (fn)->find_slot_with_hash ((tree)&in, + DECL_UID (var), + NO_INSERT); + if (loc) + { + SSA_NAME_IS_DEFAULT_DEF (*(tree *)loc) = false; + DEFAULT_DEFS (fn)->clear_slot (loc); + } + return; + } + gcc_assert (TREE_CODE (def) == SSA_NAME && SSA_NAME_VAR (def) == var); + tree *loc = DEFAULT_DEFS (fn)->find_slot_with_hash ((tree)&in, + DECL_UID (var), INSERT); + + /* Default definition might be changed by tail call optimization. */ + if (*loc) + SSA_NAME_IS_DEFAULT_DEF (*loc) = false; + + /* Mark DEF as the default definition for VAR. */ + *loc = def; + SSA_NAME_IS_DEFAULT_DEF (def) = true; +} + +/* Retrieve or create a default definition for VAR. */ + +tree +get_or_create_ssa_default_def (struct function *fn, tree var) +{ + tree ddef = ssa_default_def (fn, var); + if (ddef == NULL_TREE) + { + ddef = make_ssa_name_fn (fn, var, gimple_build_nop ()); + set_ssa_default_def (fn, var, ddef); + } + return ddef; +} + + +/* If EXP is a handled component reference for a structure, return the + base variable. The access range is delimited by bit positions *POFFSET and + *POFFSET + *PMAX_SIZE. The access size is *PSIZE bits. If either + *PSIZE or *PMAX_SIZE is -1, they could not be determined. If *PSIZE + and *PMAX_SIZE are equal, the access is non-variable. If *PREVERSE is + true, the storage order of the reference is reversed. */ + +tree +get_ref_base_and_extent (tree exp, poly_int64_pod *poffset, + poly_int64_pod *psize, + poly_int64_pod *pmax_size, + bool *preverse) +{ + poly_offset_int bitsize = -1; + poly_offset_int maxsize; + tree size_tree = NULL_TREE; + poly_offset_int bit_offset = 0; + bool seen_variable_array_ref = false; + + /* First get the final access size and the storage order from just the + outermost expression. */ + if (TREE_CODE (exp) == COMPONENT_REF) + size_tree = DECL_SIZE (TREE_OPERAND (exp, 1)); + else if (TREE_CODE (exp) == BIT_FIELD_REF) + size_tree = TREE_OPERAND (exp, 1); + else if (TREE_CODE (exp) == WITH_SIZE_EXPR) + { + size_tree = TREE_OPERAND (exp, 1); + exp = TREE_OPERAND (exp, 0); + } + else if (!VOID_TYPE_P (TREE_TYPE (exp))) + { + machine_mode mode = TYPE_MODE (TREE_TYPE (exp)); + if (mode == BLKmode) + size_tree = TYPE_SIZE (TREE_TYPE (exp)); + else + bitsize = GET_MODE_BITSIZE (mode); + } + if (size_tree != NULL_TREE + && poly_int_tree_p (size_tree)) + bitsize = wi::to_poly_offset (size_tree); + + *preverse = reverse_storage_order_for_component_p (exp); + + /* Initially, maxsize is the same as the accessed element size. + In the following it will only grow (or become -1). */ + maxsize = bitsize; + + /* Compute cumulative bit-offset for nested component-refs and array-refs, + and find the ultimate containing object. */ + while (1) + { + switch (TREE_CODE (exp)) + { + case BIT_FIELD_REF: + bit_offset += wi::to_poly_offset (TREE_OPERAND (exp, 2)); + break; + + case COMPONENT_REF: + { + tree field = TREE_OPERAND (exp, 1); + tree this_offset = component_ref_field_offset (exp); + + if (this_offset && poly_int_tree_p (this_offset)) + { + poly_offset_int woffset = (wi::to_poly_offset (this_offset) + << LOG2_BITS_PER_UNIT); + woffset += wi::to_offset (DECL_FIELD_BIT_OFFSET (field)); + bit_offset += woffset; + + /* If we had seen a variable array ref already and we just + referenced the last field of a struct or a union member + then we have to adjust maxsize by the padding at the end + of our field. */ + if (seen_variable_array_ref) + { + tree stype = TREE_TYPE (TREE_OPERAND (exp, 0)); + tree next = DECL_CHAIN (field); + while (next && TREE_CODE (next) != FIELD_DECL) + next = DECL_CHAIN (next); + if (!next + || TREE_CODE (stype) != RECORD_TYPE) + { + tree fsize = DECL_SIZE_UNIT (field); + tree ssize = TYPE_SIZE_UNIT (stype); + if (fsize == NULL + || !poly_int_tree_p (fsize) + || ssize == NULL + || !poly_int_tree_p (ssize)) + maxsize = -1; + else if (known_size_p (maxsize)) + { + poly_offset_int tem + = (wi::to_poly_offset (ssize) + - wi::to_poly_offset (fsize)); + tem <<= LOG2_BITS_PER_UNIT; + tem -= woffset; + maxsize += tem; + } + } + /* An component ref with an adjacent field up in the + structure hierarchy constrains the size of any variable + array ref lower in the access hierarchy. */ + else + seen_variable_array_ref = false; + } + } + else + { + tree csize = TYPE_SIZE (TREE_TYPE (TREE_OPERAND (exp, 0))); + /* We need to adjust maxsize to the whole structure bitsize. + But we can subtract any constant offset seen so far, + because that would get us out of the structure otherwise. */ + if (known_size_p (maxsize) + && csize + && poly_int_tree_p (csize)) + maxsize = wi::to_poly_offset (csize) - bit_offset; + else + maxsize = -1; + } + } + break; + + case ARRAY_REF: + case ARRAY_RANGE_REF: + { + tree index = TREE_OPERAND (exp, 1); + tree low_bound, unit_size; + + /* If the resulting bit-offset is constant, track it. */ + if (poly_int_tree_p (index) + && (low_bound = array_ref_low_bound (exp), + poly_int_tree_p (low_bound)) + && (unit_size = array_ref_element_size (exp), + TREE_CODE (unit_size) == INTEGER_CST)) + { + poly_offset_int woffset + = wi::sext (wi::to_poly_offset (index) + - wi::to_poly_offset (low_bound), + TYPE_PRECISION (sizetype)); + woffset *= wi::to_offset (unit_size); + woffset <<= LOG2_BITS_PER_UNIT; + bit_offset += woffset; + + /* An array ref with a constant index up in the structure + hierarchy will constrain the size of any variable array ref + lower in the access hierarchy. */ + seen_variable_array_ref = false; + } + else + { + tree asize = TYPE_SIZE (TREE_TYPE (TREE_OPERAND (exp, 0))); + /* We need to adjust maxsize to the whole array bitsize. + But we can subtract any constant offset seen so far, + because that would get us outside of the array otherwise. */ + if (known_size_p (maxsize) + && asize + && poly_int_tree_p (asize)) + maxsize = wi::to_poly_offset (asize) - bit_offset; + else + maxsize = -1; + + /* Remember that we have seen an array ref with a variable + index. */ + seen_variable_array_ref = true; + + value_range vr; + range_query *query; + if (cfun) + query = get_range_query (cfun); + else + query = get_global_range_query (); + + if (TREE_CODE (index) == SSA_NAME + && (low_bound = array_ref_low_bound (exp), + poly_int_tree_p (low_bound)) + && (unit_size = array_ref_element_size (exp), + TREE_CODE (unit_size) == INTEGER_CST) + && query->range_of_expr (vr, index) + && vr.kind () == VR_RANGE) + { + wide_int min = vr.lower_bound (); + wide_int max = vr.upper_bound (); + poly_offset_int lbound = wi::to_poly_offset (low_bound); + /* Try to constrain maxsize with range information. */ + offset_int omax + = offset_int::from (max, TYPE_SIGN (TREE_TYPE (index))); + if (known_lt (lbound, omax)) + { + poly_offset_int rmaxsize; + rmaxsize = (omax - lbound + 1) + * wi::to_offset (unit_size) << LOG2_BITS_PER_UNIT; + if (!known_size_p (maxsize) + || known_lt (rmaxsize, maxsize)) + { + /* If we know an upper bound below the declared + one this is no longer variable. */ + if (known_size_p (maxsize)) + seen_variable_array_ref = false; + maxsize = rmaxsize; + } + } + /* Try to adjust bit_offset with range information. */ + offset_int omin + = offset_int::from (min, TYPE_SIGN (TREE_TYPE (index))); + if (known_le (lbound, omin)) + { + poly_offset_int woffset + = wi::sext (omin - lbound, + TYPE_PRECISION (sizetype)); + woffset *= wi::to_offset (unit_size); + woffset <<= LOG2_BITS_PER_UNIT; + bit_offset += woffset; + if (known_size_p (maxsize)) + maxsize -= woffset; + } + } + } + } + break; + + case REALPART_EXPR: + break; + + case IMAGPART_EXPR: + bit_offset += bitsize; + break; + + case VIEW_CONVERT_EXPR: + break; + + case TARGET_MEM_REF: + /* Via the variable index or index2 we can reach the + whole object. Still hand back the decl here. */ + if (TREE_CODE (TMR_BASE (exp)) == ADDR_EXPR + && (TMR_INDEX (exp) || TMR_INDEX2 (exp))) + { + exp = TREE_OPERAND (TMR_BASE (exp), 0); + bit_offset = 0; + maxsize = -1; + goto done; + } + /* Fallthru. */ + case MEM_REF: + /* We need to deal with variable arrays ending structures such as + struct { int length; int a[1]; } x; x.a[d] + struct { struct { int a; int b; } a[1]; } x; x.a[d].a + struct { struct { int a[1]; } a[1]; } x; x.a[0][d], x.a[d][0] + struct { int len; union { int a[1]; struct X x; } u; } x; x.u.a[d] + where we do not know maxsize for variable index accesses to + the array. The simplest way to conservatively deal with this + is to punt in the case that offset + maxsize reaches the + base type boundary. This needs to include possible trailing + padding that is there for alignment purposes. */ + if (seen_variable_array_ref + && known_size_p (maxsize) + && (TYPE_SIZE (TREE_TYPE (exp)) == NULL_TREE + || !poly_int_tree_p (TYPE_SIZE (TREE_TYPE (exp))) + || (maybe_eq + (bit_offset + maxsize, + wi::to_poly_offset (TYPE_SIZE (TREE_TYPE (exp))))))) + maxsize = -1; + + /* Hand back the decl for MEM[&decl, off]. */ + if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR) + { + if (integer_zerop (TREE_OPERAND (exp, 1))) + exp = TREE_OPERAND (TREE_OPERAND (exp, 0), 0); + else + { + poly_offset_int off = mem_ref_offset (exp); + off <<= LOG2_BITS_PER_UNIT; + off += bit_offset; + poly_int64 off_hwi; + if (off.to_shwi (&off_hwi)) + { + bit_offset = off_hwi; + exp = TREE_OPERAND (TREE_OPERAND (exp, 0), 0); + } + } + } + goto done; + + default: + goto done; + } + + exp = TREE_OPERAND (exp, 0); + } + + done: + if (!bitsize.to_shwi (psize) || maybe_lt (*psize, 0)) + { + *poffset = 0; + *psize = -1; + *pmax_size = -1; + + return exp; + } + + /* ??? Due to negative offsets in ARRAY_REF we can end up with + negative bit_offset here. We might want to store a zero offset + in this case. */ + if (!bit_offset.to_shwi (poffset)) + { + *poffset = 0; + *pmax_size = -1; + + return exp; + } + + /* In case of a decl or constant base object we can do better. */ + + if (DECL_P (exp)) + { + if (VAR_P (exp) + && ((flag_unconstrained_commons && DECL_COMMON (exp)) + || (DECL_EXTERNAL (exp) && seen_variable_array_ref))) + { + tree sz_tree = TYPE_SIZE (TREE_TYPE (exp)); + /* If size is unknown, or we have read to the end, assume there + may be more to the structure than we are told. */ + if (TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE + || (seen_variable_array_ref + && (sz_tree == NULL_TREE + || !poly_int_tree_p (sz_tree) + || maybe_eq (bit_offset + maxsize, + wi::to_poly_offset (sz_tree))))) + maxsize = -1; + } + /* If maxsize is unknown adjust it according to the size of the + base decl. */ + else if (!known_size_p (maxsize) + && DECL_SIZE (exp) + && poly_int_tree_p (DECL_SIZE (exp))) + maxsize = wi::to_poly_offset (DECL_SIZE (exp)) - bit_offset; + } + else if (CONSTANT_CLASS_P (exp)) + { + /* If maxsize is unknown adjust it according to the size of the + base type constant. */ + if (!known_size_p (maxsize) + && TYPE_SIZE (TREE_TYPE (exp)) + && poly_int_tree_p (TYPE_SIZE (TREE_TYPE (exp)))) + maxsize = (wi::to_poly_offset (TYPE_SIZE (TREE_TYPE (exp))) + - bit_offset); + } + + if (!maxsize.to_shwi (pmax_size) + || maybe_lt (*pmax_size, 0) + || !endpoint_representable_p (*poffset, *pmax_size)) + *pmax_size = -1; + + /* Punt if *POFFSET + *PSIZE overflows in HOST_WIDE_INT, the callers don't + check for such overflows individually and assume it works. */ + if (!endpoint_representable_p (*poffset, *psize)) + { + *poffset = 0; + *psize = -1; + *pmax_size = -1; + + return exp; + } + + return exp; +} + +/* Like get_ref_base_and_extent, but for cases in which we only care + about constant-width accesses at constant offsets. Return null + if the access is anything else. */ + +tree +get_ref_base_and_extent_hwi (tree exp, HOST_WIDE_INT *poffset, + HOST_WIDE_INT *psize, bool *preverse) +{ + poly_int64 offset, size, max_size; + HOST_WIDE_INT const_offset, const_size; + bool reverse; + tree decl = get_ref_base_and_extent (exp, &offset, &size, &max_size, + &reverse); + if (!offset.is_constant (&const_offset) + || !size.is_constant (&const_size) + || const_offset < 0 + || !known_size_p (max_size) + || maybe_ne (max_size, const_size)) + return NULL_TREE; + + *poffset = const_offset; + *psize = const_size; + *preverse = reverse; + return decl; +} + +/* Returns the base object and a constant BITS_PER_UNIT offset in *POFFSET that + denotes the starting address of the memory access EXP. + Returns NULL_TREE if the offset is not constant or any component + is not BITS_PER_UNIT-aligned. + VALUEIZE if non-NULL is used to valueize SSA names. It should return + its argument or a constant if the argument is known to be constant. */ + +tree +get_addr_base_and_unit_offset_1 (tree exp, poly_int64_pod *poffset, + tree (*valueize) (tree)) +{ + poly_int64 byte_offset = 0; + + /* Compute cumulative byte-offset for nested component-refs and array-refs, + and find the ultimate containing object. */ + while (1) + { + switch (TREE_CODE (exp)) + { + case BIT_FIELD_REF: + { + poly_int64 this_byte_offset; + poly_uint64 this_bit_offset; + if (!poly_int_tree_p (TREE_OPERAND (exp, 2), &this_bit_offset) + || !multiple_p (this_bit_offset, BITS_PER_UNIT, + &this_byte_offset)) + return NULL_TREE; + byte_offset += this_byte_offset; + } + break; + + case COMPONENT_REF: + { + tree field = TREE_OPERAND (exp, 1); + tree this_offset = component_ref_field_offset (exp); + poly_int64 hthis_offset; + + if (!this_offset + || !poly_int_tree_p (this_offset, &hthis_offset) + || (TREE_INT_CST_LOW (DECL_FIELD_BIT_OFFSET (field)) + % BITS_PER_UNIT)) + return NULL_TREE; + + hthis_offset += (TREE_INT_CST_LOW (DECL_FIELD_BIT_OFFSET (field)) + / BITS_PER_UNIT); + byte_offset += hthis_offset; + } + break; + + case ARRAY_REF: + case ARRAY_RANGE_REF: + { + tree index = TREE_OPERAND (exp, 1); + tree low_bound, unit_size; + + if (valueize + && TREE_CODE (index) == SSA_NAME) + index = (*valueize) (index); + if (!poly_int_tree_p (index)) + return NULL_TREE; + low_bound = array_ref_low_bound (exp); + if (valueize + && TREE_CODE (low_bound) == SSA_NAME) + low_bound = (*valueize) (low_bound); + if (!poly_int_tree_p (low_bound)) + return NULL_TREE; + unit_size = array_ref_element_size (exp); + if (TREE_CODE (unit_size) != INTEGER_CST) + return NULL_TREE; + + /* If the resulting bit-offset is constant, track it. */ + poly_offset_int woffset + = wi::sext (wi::to_poly_offset (index) + - wi::to_poly_offset (low_bound), + TYPE_PRECISION (sizetype)); + woffset *= wi::to_offset (unit_size); + byte_offset += woffset.force_shwi (); + } + break; + + case REALPART_EXPR: + break; + + case IMAGPART_EXPR: + byte_offset += TREE_INT_CST_LOW (TYPE_SIZE_UNIT (TREE_TYPE (exp))); + break; + + case VIEW_CONVERT_EXPR: + break; + + case MEM_REF: + { + tree base = TREE_OPERAND (exp, 0); + if (valueize + && TREE_CODE (base) == SSA_NAME) + base = (*valueize) (base); + + /* Hand back the decl for MEM[&decl, off]. */ + if (TREE_CODE (base) == ADDR_EXPR) + { + if (!integer_zerop (TREE_OPERAND (exp, 1))) + { + poly_offset_int off = mem_ref_offset (exp); + byte_offset += off.force_shwi (); + } + exp = TREE_OPERAND (base, 0); + } + goto done; + } + + case TARGET_MEM_REF: + { + tree base = TREE_OPERAND (exp, 0); + if (valueize + && TREE_CODE (base) == SSA_NAME) + base = (*valueize) (base); + + /* Hand back the decl for MEM[&decl, off]. */ + if (TREE_CODE (base) == ADDR_EXPR) + { + if (TMR_INDEX (exp) || TMR_INDEX2 (exp)) + return NULL_TREE; + if (!integer_zerop (TMR_OFFSET (exp))) + { + poly_offset_int off = mem_ref_offset (exp); + byte_offset += off.force_shwi (); + } + exp = TREE_OPERAND (base, 0); + } + goto done; + } + + default: + goto done; + } + + exp = TREE_OPERAND (exp, 0); + } +done: + + *poffset = byte_offset; + return exp; +} + +/* Returns the base object and a constant BITS_PER_UNIT offset in *POFFSET that + denotes the starting address of the memory access EXP. + Returns NULL_TREE if the offset is not constant or any component + is not BITS_PER_UNIT-aligned. */ + +tree +get_addr_base_and_unit_offset (tree exp, poly_int64_pod *poffset) +{ + return get_addr_base_and_unit_offset_1 (exp, poffset, NULL); +} + +/* Returns true if STMT references an SSA_NAME that has + SSA_NAME_OCCURS_IN_ABNORMAL_PHI set, otherwise false. */ + +bool +stmt_references_abnormal_ssa_name (gimple *stmt) +{ + ssa_op_iter oi; + use_operand_p use_p; + + FOR_EACH_SSA_USE_OPERAND (use_p, stmt, oi, SSA_OP_USE) + { + if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (USE_FROM_PTR (use_p))) + return true; + } + + return false; +} + +/* If STMT takes any abnormal PHI values as input, replace them with + local copies. */ + +void +replace_abnormal_ssa_names (gimple *stmt) +{ + ssa_op_iter oi; + use_operand_p use_p; + + FOR_EACH_SSA_USE_OPERAND (use_p, stmt, oi, SSA_OP_USE) + { + tree op = USE_FROM_PTR (use_p); + if (TREE_CODE (op) == SSA_NAME && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (op)) + { + gimple_stmt_iterator gsi = gsi_for_stmt (stmt); + tree new_name = make_ssa_name (TREE_TYPE (op)); + gassign *assign = gimple_build_assign (new_name, op); + gsi_insert_before (&gsi, assign, GSI_SAME_STMT); + SET_USE (use_p, new_name); + } + } +} + +/* Pair of tree and a sorting index, for dump_enumerated_decls. */ +struct GTY(()) numbered_tree +{ + tree t; + int num; +}; + + +/* Compare two declarations references by their DECL_UID / sequence number. + Called via qsort. */ + +static int +compare_decls_by_uid (const void *pa, const void *pb) +{ + const numbered_tree *nt_a = ((const numbered_tree *)pa); + const numbered_tree *nt_b = ((const numbered_tree *)pb); + + if (DECL_UID (nt_a->t) != DECL_UID (nt_b->t)) + return DECL_UID (nt_a->t) - DECL_UID (nt_b->t); + return nt_a->num - nt_b->num; +} + +/* Called via walk_gimple_stmt / walk_gimple_op by dump_enumerated_decls. */ +static tree +dump_enumerated_decls_push (tree *tp, int *walk_subtrees, void *data) +{ + struct walk_stmt_info *wi = (struct walk_stmt_info *) data; + vec<numbered_tree> *list = (vec<numbered_tree> *) wi->info; + numbered_tree nt; + + if (!DECL_P (*tp)) + return NULL_TREE; + nt.t = *tp; + nt.num = list->length (); + list->safe_push (nt); + *walk_subtrees = 0; + return NULL_TREE; +} + +/* Find all the declarations used by the current function, sort them by uid, + and emit the sorted list. Each declaration is tagged with a sequence + number indicating when it was found during statement / tree walking, + so that TDF_NOUID comparisons of anonymous declarations are still + meaningful. Where a declaration was encountered more than once, we + emit only the sequence number of the first encounter. + FILE is the dump file where to output the list and FLAGS is as in + print_generic_expr. */ +void +dump_enumerated_decls (FILE *file, dump_flags_t flags) +{ + if (!cfun->cfg) + return; + + basic_block bb; + struct walk_stmt_info wi; + auto_vec<numbered_tree, 40> decl_list; + + memset (&wi, '\0', sizeof (wi)); + wi.info = (void *) &decl_list; + FOR_EACH_BB_FN (bb, cfun) + { + gimple_stmt_iterator gsi; + + for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) + if (!is_gimple_debug (gsi_stmt (gsi))) + walk_gimple_stmt (&gsi, NULL, dump_enumerated_decls_push, &wi); + } + decl_list.qsort (compare_decls_by_uid); + if (decl_list.length ()) + { + unsigned ix; + numbered_tree *ntp; + tree last = NULL_TREE; + + fprintf (file, "Declarations used by %s, sorted by DECL_UID:\n", + current_function_name ()); + FOR_EACH_VEC_ELT (decl_list, ix, ntp) + { + if (ntp->t == last) + continue; + fprintf (file, "%d: ", ntp->num); + print_generic_decl (file, ntp->t, flags); + fprintf (file, "\n"); + last = ntp->t; + } + } +} |