| /* RTL manipulation functions exported by Pointer Bounds Checker. |
| Copyright (C) 2014-2017 Free Software Foundation, Inc. |
| Contributed by Ilya Enkovich (ilya.enkovich@intel.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 "target.h" |
| #include "rtl.h" |
| #include "tree.h" |
| #include "memmodel.h" |
| #include "emit-rtl.h" |
| #include "expr.h" |
| #include "rtl-chkp.h" |
| #include "tree-chkp.h" |
| |
| static hash_map<tree, rtx> *chkp_rtx_bounds_map; |
| |
| /* Get bounds rtx associated with NODE via |
| chkp_set_rtl_bounds call. */ |
| rtx |
| chkp_get_rtl_bounds (tree node) |
| { |
| rtx *slot; |
| |
| if (!chkp_rtx_bounds_map) |
| return NULL_RTX; |
| |
| slot = chkp_rtx_bounds_map->get (node); |
| return slot ? *slot : NULL_RTX; |
| } |
| |
| /* Associate bounds rtx VAL with NODE. */ |
| void |
| chkp_set_rtl_bounds (tree node, rtx val) |
| { |
| if (!chkp_rtx_bounds_map) |
| chkp_rtx_bounds_map = new hash_map<tree, rtx>; |
| |
| chkp_rtx_bounds_map->put (node, val); |
| } |
| |
| /* Reset all bounds stored via chkp_set_rtl_bounds. */ |
| void |
| chkp_reset_rtl_bounds () |
| { |
| if (!chkp_rtx_bounds_map) |
| return; |
| |
| delete chkp_rtx_bounds_map; |
| chkp_rtx_bounds_map = NULL; |
| } |
| |
| /* Split SLOT identifying slot for function value or |
| argument into two parts SLOT_VAL and SLOT_BND. |
| First is the slot for regular value and the other one is |
| for bounds. */ |
| void |
| chkp_split_slot (rtx slot, rtx *slot_val, rtx *slot_bnd) |
| { |
| int i; |
| int val_num = 0; |
| int bnd_num = 0; |
| rtx *val_tmps; |
| rtx *bnd_tmps; |
| |
| *slot_bnd = 0; |
| |
| if (!slot |
| || GET_CODE (slot) != PARALLEL) |
| { |
| *slot_val = slot; |
| return; |
| } |
| |
| val_tmps = XALLOCAVEC (rtx, XVECLEN (slot, 0)); |
| bnd_tmps = XALLOCAVEC (rtx, XVECLEN (slot, 0)); |
| |
| for (i = 0; i < XVECLEN (slot, 0); i++) |
| { |
| rtx elem = XVECEXP (slot, 0, i); |
| rtx reg = GET_CODE (elem) == EXPR_LIST ? XEXP (elem, 0) : elem; |
| |
| if (!reg) |
| continue; |
| |
| if (POINTER_BOUNDS_MODE_P (GET_MODE (reg)) || CONST_INT_P (reg)) |
| bnd_tmps[bnd_num++] = elem; |
| else |
| val_tmps[val_num++] = elem; |
| } |
| |
| gcc_assert (val_num); |
| |
| if (!bnd_num) |
| { |
| *slot_val = slot; |
| return; |
| } |
| |
| if ((GET_CODE (val_tmps[0]) == EXPR_LIST) || (val_num > 1)) |
| *slot_val = gen_rtx_PARALLEL (GET_MODE (slot), |
| gen_rtvec_v (val_num, val_tmps)); |
| else |
| *slot_val = val_tmps[0]; |
| |
| if ((GET_CODE (bnd_tmps[0]) == EXPR_LIST) || (bnd_num > 1)) |
| *slot_bnd = gen_rtx_PARALLEL (VOIDmode, |
| gen_rtvec_v (bnd_num, bnd_tmps)); |
| else |
| *slot_bnd = bnd_tmps[0]; |
| } |
| |
| /* Join previously splitted to VAL and BND rtx for function |
| value or argument and return it. */ |
| rtx |
| chkp_join_splitted_slot (rtx val, rtx bnd) |
| { |
| rtx res; |
| int i, n = 0; |
| |
| if (!bnd) |
| return val; |
| |
| if (GET_CODE (val) == PARALLEL) |
| n += XVECLEN (val, 0); |
| else |
| n++; |
| |
| if (GET_CODE (bnd) == PARALLEL) |
| n += XVECLEN (bnd, 0); |
| else |
| n++; |
| |
| res = gen_rtx_PARALLEL (GET_MODE (val), rtvec_alloc (n)); |
| |
| n = 0; |
| |
| if (GET_CODE (val) == PARALLEL) |
| for (i = 0; i < XVECLEN (val, 0); i++) |
| XVECEXP (res, 0, n++) = XVECEXP (val, 0, i); |
| else |
| XVECEXP (res, 0, n++) = val; |
| |
| if (GET_CODE (bnd) == PARALLEL) |
| for (i = 0; i < XVECLEN (bnd, 0); i++) |
| XVECEXP (res, 0, n++) = XVECEXP (bnd, 0, i); |
| else |
| XVECEXP (res, 0, n++) = bnd; |
| |
| return res; |
| } |
| |
| /* If PAR is PARALLEL holding registers then transform |
| it into PARALLEL holding EXPR_LISTs of those regs |
| and zero constant (similar to how function value |
| on multiple registers looks like). */ |
| void |
| chkp_put_regs_to_expr_list (rtx par) |
| { |
| int n; |
| |
| if (GET_CODE (par) != PARALLEL |
| || GET_CODE (XVECEXP (par, 0, 0)) == EXPR_LIST) |
| return; |
| |
| for (n = 0; n < XVECLEN (par, 0); n++) |
| XVECEXP (par, 0, n) = gen_rtx_EXPR_LIST (VOIDmode, |
| XVECEXP (par, 0, n), |
| const0_rtx); |
| } |
| |
| /* Search rtx PAR describing function return value for an |
| item related to value at offset OFFS and return it. |
| Return NULL if item was not found. */ |
| rtx |
| chkp_get_value_with_offs (rtx par, rtx offs) |
| { |
| int n; |
| |
| gcc_assert (GET_CODE (par) == PARALLEL); |
| |
| for (n = 0; n < XVECLEN (par, 0); n++) |
| { |
| rtx par_offs = XEXP (XVECEXP (par, 0, n), 1); |
| if (INTVAL (offs) == INTVAL (par_offs)) |
| return XEXP (XVECEXP (par, 0, n), 0); |
| } |
| |
| return NULL; |
| } |
| |
| /* Emit instructions to store BOUNDS for pointer VALUE |
| stored in MEM. |
| Function is used by expand to pass bounds for args |
| passed on stack. */ |
| void |
| chkp_emit_bounds_store (rtx bounds, rtx value, rtx mem) |
| { |
| gcc_assert (MEM_P (mem)); |
| |
| if (REG_P (bounds) || CONST_INT_P (bounds)) |
| { |
| rtx ptr; |
| |
| if (REG_P (value)) |
| ptr = value; |
| else |
| { |
| rtx slot = adjust_address (value, Pmode, 0); |
| ptr = gen_reg_rtx (Pmode); |
| emit_move_insn (ptr, slot); |
| } |
| |
| if (CONST_INT_P (bounds)) |
| bounds = targetm.calls.load_bounds_for_arg (value, ptr, bounds); |
| |
| targetm.calls.store_bounds_for_arg (ptr, mem, |
| bounds, NULL); |
| } |
| else |
| { |
| int i; |
| |
| gcc_assert (GET_CODE (bounds) == PARALLEL); |
| gcc_assert (GET_CODE (value) == PARALLEL || MEM_P (value) || REG_P (value)); |
| |
| for (i = 0; i < XVECLEN (bounds, 0); i++) |
| { |
| rtx reg = XEXP (XVECEXP (bounds, 0, i), 0); |
| rtx offs = XEXP (XVECEXP (bounds, 0, i), 1); |
| rtx slot = adjust_address (mem, Pmode, INTVAL (offs)); |
| rtx ptr; |
| |
| if (GET_CODE (value) == PARALLEL) |
| ptr = chkp_get_value_with_offs (value, offs); |
| else if (MEM_P (value)) |
| { |
| rtx tmp = adjust_address (value, Pmode, INTVAL (offs)); |
| ptr = gen_reg_rtx (Pmode); |
| emit_move_insn (ptr, tmp); |
| } |
| else |
| ptr = gen_rtx_SUBREG (Pmode, value, INTVAL (offs)); |
| |
| targetm.calls.store_bounds_for_arg (ptr, slot, reg, NULL); |
| } |
| } |
| } |
| |
| /* Emit code to copy bounds for structure VALUE of type TYPE |
| copied to SLOT. */ |
| void |
| chkp_copy_bounds_for_stack_parm (rtx slot, rtx value, tree type) |
| { |
| bitmap have_bound; |
| bitmap_iterator bi; |
| unsigned i; |
| rtx tmp = NULL, bnd; |
| |
| gcc_assert (TYPE_SIZE (type)); |
| gcc_assert (MEM_P (value)); |
| gcc_assert (MEM_P (slot)); |
| gcc_assert (RECORD_OR_UNION_TYPE_P (type)); |
| |
| bitmap_obstack_initialize (NULL); |
| have_bound = BITMAP_ALLOC (NULL); |
| chkp_find_bound_slots (type, have_bound); |
| |
| EXECUTE_IF_SET_IN_BITMAP (have_bound, 0, i, bi) |
| { |
| rtx ptr = adjust_address (value, Pmode, i * POINTER_SIZE / 8); |
| rtx to = adjust_address (slot, Pmode, i * POINTER_SIZE / 8); |
| |
| if (!tmp) |
| tmp = gen_reg_rtx (Pmode); |
| |
| emit_move_insn (tmp, ptr); |
| bnd = targetm.calls.load_bounds_for_arg (ptr, tmp, NULL); |
| targetm.calls.store_bounds_for_arg (tmp, to, bnd, NULL); |
| } |
| |
| BITMAP_FREE (have_bound); |
| bitmap_obstack_release (NULL); |
| } |