Exemple #1
0
void
ubsan_expand_bounds_ifn (gimple_stmt_iterator *gsi)
{
  gimple stmt = gsi_stmt (*gsi);
  location_t loc = gimple_location (stmt);
  gcc_assert (gimple_call_num_args (stmt) == 3);

  /* Pick up the arguments of the UBSAN_BOUNDS call.  */
  tree type = TREE_TYPE (TREE_TYPE (gimple_call_arg (stmt, 0)));
  tree index = gimple_call_arg (stmt, 1);
  tree orig_index_type = TREE_TYPE (index);
  tree bound = gimple_call_arg (stmt, 2);

  gimple_stmt_iterator gsi_orig = *gsi;

  /* Create condition "if (index > bound)".  */
  basic_block then_bb, fallthru_bb;
  gimple_stmt_iterator cond_insert_point
    = create_cond_insert_point (gsi, 0/*before_p*/, false, true,
				&then_bb, &fallthru_bb);
  index = fold_convert (TREE_TYPE (bound), index);
  index = force_gimple_operand_gsi (&cond_insert_point, index,
				    true/*simple_p*/, NULL_TREE,
				    false/*before*/, GSI_NEW_STMT);
  gimple g = gimple_build_cond (GT_EXPR, index, bound, NULL_TREE, NULL_TREE);
  gimple_set_location (g, loc);
  gsi_insert_after (&cond_insert_point, g, GSI_NEW_STMT);

  /* Generate __ubsan_handle_out_of_bounds call.  */
  *gsi = gsi_after_labels (then_bb);
  if (flag_sanitize_undefined_trap_on_error)
    g = gimple_build_call (builtin_decl_explicit (BUILT_IN_TRAP), 0);
  else
    {
      tree data
	= ubsan_create_data ("__ubsan_out_of_bounds_data", &loc, NULL,
			     ubsan_type_descriptor (type, UBSAN_PRINT_ARRAY),
			     ubsan_type_descriptor (orig_index_type),
			     NULL_TREE);
      data = build_fold_addr_expr_loc (loc, data);
      enum built_in_function bcode
	= flag_sanitize_recover
	  ? BUILT_IN_UBSAN_HANDLE_OUT_OF_BOUNDS
	  : BUILT_IN_UBSAN_HANDLE_OUT_OF_BOUNDS_ABORT;
      tree fn = builtin_decl_explicit (bcode);
      tree val = force_gimple_operand_gsi (gsi, ubsan_encode_value (index),
					   true, NULL_TREE, true,
					   GSI_SAME_STMT);
      g = gimple_build_call (fn, 2, data, val);
    }
  gimple_set_location (g, loc);
  gsi_insert_before (gsi, g, GSI_SAME_STMT);

  /* Get rid of the UBSAN_BOUNDS call from the IR.  */
  unlink_stmt_vdef (stmt);
  gsi_remove (&gsi_orig, true);

  /* Point GSI to next logical statement.  */
  *gsi = gsi_start_bb (fallthru_bb);
}
static void
lower_builtin_posix_memalign (gimple_stmt_iterator *gsi)
{
  gimple stmt, call = gsi_stmt (*gsi);
  tree pptr = gimple_call_arg (call, 0);
  tree align = gimple_call_arg (call, 1);
  tree res = gimple_call_lhs (call);
  tree ptr = create_tmp_reg (ptr_type_node, NULL);
  if (TREE_CODE (pptr) == ADDR_EXPR)
    {
      tree tem = create_tmp_var (ptr_type_node, NULL);
      TREE_ADDRESSABLE (tem) = 1;
      gimple_call_set_arg (call, 0, build_fold_addr_expr (tem));
      stmt = gimple_build_assign (ptr, tem);
    }
  else
    stmt = gimple_build_assign (ptr,
				fold_build2 (MEM_REF, ptr_type_node, pptr,
					     build_int_cst (ptr_type_node, 0)));
  if (res == NULL_TREE)
    {
      res = create_tmp_reg (integer_type_node, NULL);
      gimple_call_set_lhs (call, res);
    }
  tree align_label = create_artificial_label (UNKNOWN_LOCATION);
  tree noalign_label = create_artificial_label (UNKNOWN_LOCATION);
  gimple cond = gimple_build_cond (EQ_EXPR, res, integer_zero_node,
				   align_label, noalign_label);
  gsi_insert_after (gsi, cond, GSI_NEW_STMT);
  gsi_insert_after (gsi, gimple_build_label (align_label), GSI_NEW_STMT);
  gsi_insert_after (gsi, stmt, GSI_NEW_STMT);
  stmt = gimple_build_call (builtin_decl_implicit (BUILT_IN_ASSUME_ALIGNED),
			    2, ptr, align);
  gimple_call_set_lhs (stmt, ptr);
  gsi_insert_after (gsi, stmt, GSI_NEW_STMT);
  stmt = gimple_build_assign (fold_build2 (MEM_REF, ptr_type_node, pptr,
					   build_int_cst (ptr_type_node, 0)),
			      ptr);
  gsi_insert_after (gsi, stmt, GSI_NEW_STMT);
  gsi_insert_after (gsi, gimple_build_label (noalign_label), GSI_NEW_STMT);
}
Exemple #3
0
static void
mf_build_check_statement_for (tree base, tree limit,
                              gimple_stmt_iterator *instr_gsi,
                              location_t location, tree dirflag)
{
  gimple_stmt_iterator gsi;
  basic_block cond_bb, then_bb, join_bb;
  edge e;
  tree cond, t, u, v;
  tree mf_base;
  tree mf_elem;
  tree mf_limit;
  gimple g;
  gimple_seq seq, stmts;

  /* We first need to split the current basic block, and start altering
     the CFG.  This allows us to insert the statements we're about to
     construct into the right basic blocks.  */

  cond_bb = gimple_bb (gsi_stmt (*instr_gsi));
  gsi = *instr_gsi;
  gsi_prev (&gsi);
  if (! gsi_end_p (gsi))
    e = split_block (cond_bb, gsi_stmt (gsi));
  else
    e = split_block_after_labels (cond_bb);
  cond_bb = e->src;
  join_bb = e->dest;

  /* A recap at this point: join_bb is the basic block at whose head
     is the gimple statement for which this check expression is being
     built.  cond_bb is the (possibly new, synthetic) basic block the
     end of which will contain the cache-lookup code, and a
     conditional that jumps to the cache-miss code or, much more
     likely, over to join_bb.  */

  /* Create the bb that contains the cache-miss fallback block (mf_check).  */
  then_bb = create_empty_bb (cond_bb);
  make_edge (cond_bb, then_bb, EDGE_TRUE_VALUE);
  make_single_succ_edge (then_bb, join_bb, EDGE_FALLTHRU);

  /* Mark the pseudo-fallthrough edge from cond_bb to join_bb.  */
  e = find_edge (cond_bb, join_bb);
  e->flags = EDGE_FALSE_VALUE;
  e->count = cond_bb->count;
  e->probability = REG_BR_PROB_BASE;

  /* Update dominance info.  Note that bb_join's data was
     updated by split_block.  */
  if (dom_info_available_p (CDI_DOMINATORS))
    {
      set_immediate_dominator (CDI_DOMINATORS, then_bb, cond_bb);
      set_immediate_dominator (CDI_DOMINATORS, join_bb, cond_bb);
    }

  /* Update loop info.  */
  if (current_loops)
    add_bb_to_loop (then_bb, cond_bb->loop_father);

  /* Build our local variables.  */
  mf_elem = create_tmp_reg (mf_cache_structptr_type, "__mf_elem");
  mf_base = create_tmp_reg (mf_uintptr_type, "__mf_base");
  mf_limit = create_tmp_reg (mf_uintptr_type, "__mf_limit");

  /* Build: __mf_base = (uintptr_t) <base address expression>.  */
  seq = NULL;
  t = fold_convert_loc (location, mf_uintptr_type,
			unshare_expr (base));
  t = force_gimple_operand (t, &stmts, false, NULL_TREE);
  gimple_seq_add_seq (&seq, stmts);
  g = gimple_build_assign (mf_base, t);
  gimple_set_location (g, location);
  gimple_seq_add_stmt (&seq, g);

  /* Build: __mf_limit = (uintptr_t) <limit address expression>.  */
  t = fold_convert_loc (location, mf_uintptr_type,
			unshare_expr (limit));
  t = force_gimple_operand (t, &stmts, false, NULL_TREE);
  gimple_seq_add_seq (&seq, stmts);
  g = gimple_build_assign (mf_limit, t);
  gimple_set_location (g, location);
  gimple_seq_add_stmt (&seq, g);

  /* Build: __mf_elem = &__mf_lookup_cache [(__mf_base >> __mf_shift)
                                            & __mf_mask].  */
  t = build2 (RSHIFT_EXPR, mf_uintptr_type, mf_base,
              flag_mudflap_threads ? mf_cache_shift_decl
	       : mf_cache_shift_decl_l);
  t = build2 (BIT_AND_EXPR, mf_uintptr_type, t,
              flag_mudflap_threads ? mf_cache_mask_decl
	       : mf_cache_mask_decl_l);
  t = build4 (ARRAY_REF,
              TREE_TYPE (TREE_TYPE (mf_cache_array_decl)),
              mf_cache_array_decl, t, NULL_TREE, NULL_TREE);
  t = build1 (ADDR_EXPR, mf_cache_structptr_type, t);
  t = force_gimple_operand (t, &stmts, false, NULL_TREE);
  gimple_seq_add_seq (&seq, stmts);
  g = gimple_build_assign (mf_elem, t);
  gimple_set_location (g, location);
  gimple_seq_add_stmt (&seq, g);

  /* Quick validity check.

     if (__mf_elem->low > __mf_base
         || (__mf_elem_high < __mf_limit))
        {
          __mf_check ();
          ... and only if single-threaded:
          __mf_lookup_shift_1 = f...;
          __mf_lookup_mask_l = ...;
        }

     It is expected that this body of code is rarely executed so we mark
     the edge to the THEN clause of the conditional jump as unlikely.  */

  /* Construct t <-- '__mf_elem->low  > __mf_base'.  */
  t = build3 (COMPONENT_REF, mf_uintptr_type,
              build1 (INDIRECT_REF, mf_cache_struct_type, mf_elem),
              TYPE_FIELDS (mf_cache_struct_type), NULL_TREE);
  t = build2 (GT_EXPR, boolean_type_node, t, mf_base);

  /* Construct '__mf_elem->high < __mf_limit'.

     First build:
        1) u <--  '__mf_elem->high'
        2) v <--  '__mf_limit'.

     Then build 'u <-- (u < v).  */

  u = build3 (COMPONENT_REF, mf_uintptr_type,
              build1 (INDIRECT_REF, mf_cache_struct_type, mf_elem),
              DECL_CHAIN (TYPE_FIELDS (mf_cache_struct_type)), NULL_TREE);

  v = mf_limit;

  u = build2 (LT_EXPR, boolean_type_node, u, v);

  /* Build the composed conditional: t <-- 't || u'.  Then store the
     result of the evaluation of 't' in a temporary variable which we
     can use as the condition for the conditional jump.  */
  t = build2 (TRUTH_OR_EXPR, boolean_type_node, t, u);
  t = force_gimple_operand (t, &stmts, false, NULL_TREE);
  gimple_seq_add_seq (&seq, stmts);
  cond = create_tmp_reg (boolean_type_node, "__mf_unlikely_cond");
  g = gimple_build_assign  (cond, t);
  gimple_set_location (g, location);
  gimple_seq_add_stmt (&seq, g);

  /* Build the conditional jump.  'cond' is just a temporary so we can
     simply build a void COND_EXPR.  We do need labels in both arms though.  */
  g = gimple_build_cond (NE_EXPR, cond, boolean_false_node, NULL_TREE,
			 NULL_TREE);
  gimple_set_location (g, location);
  gimple_seq_add_stmt (&seq, g);

  /* At this point, after so much hard work, we have only constructed
     the conditional jump,

     if (__mf_elem->low > __mf_base
         || (__mf_elem_high < __mf_limit))

     The lowered GIMPLE tree representing this code is in the statement
     list starting at 'head'.

     We can insert this now in the current basic block, i.e. the one that
     the statement we're instrumenting was originally in.  */
  gsi = gsi_last_bb (cond_bb);
  gsi_insert_seq_after (&gsi, seq, GSI_CONTINUE_LINKING);

  /*  Now build up the body of the cache-miss handling:

     __mf_check();
     refresh *_l vars.

     This is the body of the conditional.  */

  seq = NULL;
  /* u is a string, so it is already a gimple value.  */
  u = mf_file_function_line_tree (location);
  /* NB: we pass the overall [base..limit] range to mf_check.  */
  v = fold_build2_loc (location, PLUS_EXPR, mf_uintptr_type,
		   fold_build2_loc (location,
				MINUS_EXPR, mf_uintptr_type, mf_limit, mf_base),
		   build_int_cst (mf_uintptr_type, 1));
  v = force_gimple_operand (v, &stmts, true, NULL_TREE);
  gimple_seq_add_seq (&seq, stmts);
  g = gimple_build_call (mf_check_fndecl, 4, mf_base, v, dirflag, u);
  gimple_seq_add_stmt (&seq, g);

  if (! flag_mudflap_threads)
    {
      if (stmt_ends_bb_p (g))
	{
	  gsi = gsi_start_bb (then_bb);
	  gsi_insert_seq_after (&gsi, seq, GSI_CONTINUE_LINKING);
	  e = split_block (then_bb, g);
	  then_bb = e->dest;
	  seq = NULL;
	}

      g = gimple_build_assign (mf_cache_shift_decl_l, mf_cache_shift_decl);
      gimple_seq_add_stmt (&seq, g);

      g = gimple_build_assign (mf_cache_mask_decl_l, mf_cache_mask_decl);
      gimple_seq_add_stmt (&seq, g);
    }

  /* Insert the check code in the THEN block.  */
  gsi = gsi_start_bb (then_bb);
  gsi_insert_seq_after (&gsi, seq, GSI_CONTINUE_LINKING);

  *instr_gsi = gsi_start_bb (join_bb);
}
Exemple #4
0
/* Find memcpy, mempcpy, memmove and memset calls, perform
   checks before call and then call no_chk version of
   functions.  We do it on O2 to enable inlining of these
   functions during expand.

   Also try to find memcpy, mempcpy, memmove and memset calls
   which are known to not write pointers to memory and use
   faster function versions for them.  */
static void
chkp_optimize_string_function_calls (void)
{
    basic_block bb;

    if (dump_file && (dump_flags & TDF_DETAILS))
        fprintf (dump_file, "Searching for replaceable string function calls...\n");

    FOR_EACH_BB_FN (bb, cfun)
    {
        gimple_stmt_iterator i;

        for (i = gsi_start_bb (bb); !gsi_end_p (i); gsi_next (&i))
        {
            gimple *stmt = gsi_stmt (i);
            tree fndecl;

            if (gimple_code (stmt) != GIMPLE_CALL
                    || !gimple_call_with_bounds_p (stmt))
                continue;

            fndecl = gimple_call_fndecl (stmt);

            if (!fndecl || DECL_BUILT_IN_CLASS (fndecl) != BUILT_IN_NORMAL)
                continue;

            if (DECL_FUNCTION_CODE (fndecl) == BUILT_IN_MEMCPY_CHKP
                    || DECL_FUNCTION_CODE (fndecl) == BUILT_IN_MEMPCPY_CHKP
                    || DECL_FUNCTION_CODE (fndecl) == BUILT_IN_MEMMOVE_CHKP
                    || DECL_FUNCTION_CODE (fndecl) == BUILT_IN_MEMSET_CHKP)
            {
                tree dst = gimple_call_arg (stmt, 0);
                tree dst_bnd = gimple_call_arg (stmt, 1);
                bool is_memset = DECL_FUNCTION_CODE (fndecl) == BUILT_IN_MEMSET_CHKP;
                tree size = gimple_call_arg (stmt, is_memset ? 3 : 4);
                tree fndecl_nochk;
                gimple_stmt_iterator j;
                basic_block check_bb;
                address_t size_val;
                int sign;
                bool known;

                /* We may replace call with corresponding __chkp_*_nobnd
                call in case destination pointer base type is not
                 void or pointer.  */
                if (POINTER_TYPE_P (TREE_TYPE (dst))
                        && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (dst)))
                        && !chkp_type_has_pointer (TREE_TYPE (TREE_TYPE (dst))))
                {
                    tree fndecl_nobnd
                        = chkp_get_nobnd_fndecl (DECL_FUNCTION_CODE (fndecl));

                    if (fndecl_nobnd)
                        fndecl = fndecl_nobnd;
                }

                fndecl_nochk = chkp_get_nochk_fndecl (DECL_FUNCTION_CODE (fndecl));

                if (fndecl_nochk)
                    fndecl = fndecl_nochk;

                if (fndecl != gimple_call_fndecl (stmt))
                {
                    if (dump_file && (dump_flags & TDF_DETAILS))
                    {
                        fprintf (dump_file, "Replacing call: ");
                        print_gimple_stmt (dump_file, stmt, 0,
                                           TDF_VOPS|TDF_MEMSYMS);
                    }

                    gimple_call_set_fndecl (stmt, fndecl);

                    if (dump_file && (dump_flags & TDF_DETAILS))
                    {
                        fprintf (dump_file, "With a new call: ");
                        print_gimple_stmt (dump_file, stmt, 0,
                                           TDF_VOPS|TDF_MEMSYMS);
                    }
                }

                /* If there is no nochk version of function then
                do nothing.  Otherwise insert checks before
                 the call.  */
                if (!fndecl_nochk)
                    continue;

                /* If size passed to call is known and > 0
                then we may insert checks unconditionally.  */
                size_val.pol.create (0);
                chkp_collect_value (size, size_val);
                known = chkp_is_constant_addr (size_val, &sign);
                size_val.pol.release ();

                /* If we are not sure size is not zero then we have
                to perform runtime check for size and perform
                 checks only when size is not zero.  */
                if (!known)
                {
                    gimple *check = gimple_build_cond (NE_EXPR,
                                                       size,
                                                       size_zero_node,
                                                       NULL_TREE,
                                                       NULL_TREE);

                    /* Split block before string function call.  */
                    gsi_prev (&i);
                    check_bb = insert_cond_bb (bb, gsi_stmt (i), check);

                    /* Set position for checks.  */
                    j = gsi_last_bb (check_bb);

                    /* The block was splitted and therefore we
                       need to set iterator to its end.  */
                    i = gsi_last_bb (bb);
                }
                /* If size is known to be zero then no checks
                should be performed.  */
                else if (!sign)
                    continue;
                else
                    j = i;

                size = size_binop (MINUS_EXPR, size, size_one_node);
                if (!is_memset)
                {
                    tree src = gimple_call_arg (stmt, 2);
                    tree src_bnd = gimple_call_arg (stmt, 3);

                    chkp_check_mem_access (src, fold_build_pointer_plus (src, size),
                                           src_bnd, j, gimple_location (stmt),
                                           integer_zero_node);
                }

                chkp_check_mem_access (dst, fold_build_pointer_plus (dst, size),
                                       dst_bnd, j, gimple_location (stmt),
                                       integer_one_node);

            }
        }
    }
Exemple #5
0
static void
gen_conditions_for_pow_int_base (tree base, tree expn,
                                 vec<gimple> conds,
                                 unsigned *nconds)
{
  gimple base_def;
  tree base_val0;
  tree int_type;
  tree temp, tempn;
  tree cst0;
  gimple stmt1, stmt2;
  int bit_sz, max_exp;
  inp_domain exp_domain;

  base_def = SSA_NAME_DEF_STMT (base);
  base_val0 = gimple_assign_rhs1 (base_def);
  int_type = TREE_TYPE (base_val0);
  bit_sz = TYPE_PRECISION (int_type);
  gcc_assert (bit_sz > 0
              && bit_sz <= MAX_BASE_INT_BIT_SIZE);

  /* Determine the max exp argument value according to
     the size of the base integer.  The max exp value
     is conservatively estimated assuming IEEE754 double
     precision format.  */
  if (bit_sz == 8)
    max_exp = 128;
  else if (bit_sz == 16)
    max_exp = 64;
  else
    {
      gcc_assert (bit_sz == MAX_BASE_INT_BIT_SIZE);
      max_exp = 32;
    }

  /* For pow ((double)x, y), generate the following conditions:
     cond 1:
     temp1 = x;
     if (temp1 <= 0)

     cond 2:
     temp2 = y;
     if (temp2 > max_exp_real_cst)  */

  /* Generate condition in reverse order -- first
     the condition for the exp argument.  */

  exp_domain = get_domain (0, false, false,
                           max_exp, true, true);

  gen_conditions_for_domain (expn, exp_domain,
                             conds, nconds);

  /* Now generate condition for the base argument.
     Note it does not use the helper function
     gen_conditions_for_domain because the base
     type is integer.  */

  /* Push a separator.  */
  conds.quick_push (NULL);

  temp = create_tmp_var (int_type, "DCE_COND1");
  cst0 = build_int_cst (int_type, 0);
  stmt1 = gimple_build_assign (temp, base_val0);
  tempn = make_ssa_name (temp, stmt1);
  gimple_assign_set_lhs (stmt1, tempn);
  stmt2 = gimple_build_cond (LE_EXPR, tempn, cst0, NULL_TREE, NULL_TREE);

  conds.quick_push (stmt1);
  conds.quick_push (stmt2);
  (*nconds)++;
}
Exemple #6
0
static void
instrument_bool_enum_load (gimple_stmt_iterator *gsi)
{
  gimple stmt = gsi_stmt (*gsi);
  tree rhs = gimple_assign_rhs1 (stmt);
  tree type = TREE_TYPE (rhs);
  tree minv = NULL_TREE, maxv = NULL_TREE;

  if (TREE_CODE (type) == BOOLEAN_TYPE && (flag_sanitize & SANITIZE_BOOL))
    {
      minv = boolean_false_node;
      maxv = boolean_true_node;
    }
  else if (TREE_CODE (type) == ENUMERAL_TYPE
	   && (flag_sanitize & SANITIZE_ENUM)
	   && TREE_TYPE (type) != NULL_TREE
	   && TREE_CODE (TREE_TYPE (type)) == INTEGER_TYPE
	   && (TYPE_PRECISION (TREE_TYPE (type))
	       < GET_MODE_PRECISION (TYPE_MODE (type))))
    {
      minv = TYPE_MIN_VALUE (TREE_TYPE (type));
      maxv = TYPE_MAX_VALUE (TREE_TYPE (type));
    }
  else
    return;

  int modebitsize = GET_MODE_BITSIZE (TYPE_MODE (type));
  HOST_WIDE_INT bitsize, bitpos;
  tree offset;
  enum machine_mode mode;
  int volatilep = 0, unsignedp = 0;
  tree base = get_inner_reference (rhs, &bitsize, &bitpos, &offset, &mode,
				   &unsignedp, &volatilep, false);
  tree utype = build_nonstandard_integer_type (modebitsize, 1);

  if ((TREE_CODE (base) == VAR_DECL && DECL_HARD_REGISTER (base))
      || (bitpos % modebitsize) != 0
      || bitsize != modebitsize
      || GET_MODE_BITSIZE (TYPE_MODE (utype)) != modebitsize
      || TREE_CODE (gimple_assign_lhs (stmt)) != SSA_NAME)
    return;

  location_t loc = gimple_location (stmt);
  tree ptype = build_pointer_type (TREE_TYPE (rhs));
  tree atype = reference_alias_ptr_type (rhs);
  gimple g = gimple_build_assign (make_ssa_name (ptype, NULL),
				  build_fold_addr_expr (rhs));
  gimple_set_location (g, loc);
  gsi_insert_before (gsi, g, GSI_SAME_STMT);
  tree mem = build2 (MEM_REF, utype, gimple_assign_lhs (g),
		     build_int_cst (atype, 0));
  tree urhs = make_ssa_name (utype, NULL);
  g = gimple_build_assign (urhs, mem);
  gimple_set_location (g, loc);
  gsi_insert_before (gsi, g, GSI_SAME_STMT);
  minv = fold_convert (utype, minv);
  maxv = fold_convert (utype, maxv);
  if (!integer_zerop (minv))
    {
      g = gimple_build_assign_with_ops (MINUS_EXPR,
					make_ssa_name (utype, NULL),
					urhs, minv);
      gimple_set_location (g, loc);
      gsi_insert_before (gsi, g, GSI_SAME_STMT);
    }

  gimple_stmt_iterator gsi2 = *gsi;
  basic_block then_bb, fallthru_bb;
  *gsi = create_cond_insert_point (gsi, true, false, true,
				   &then_bb, &fallthru_bb);
  g = gimple_build_cond (GT_EXPR, gimple_assign_lhs (g),
			 int_const_binop (MINUS_EXPR, maxv, minv),
			 NULL_TREE, NULL_TREE);
  gimple_set_location (g, loc);
  gsi_insert_after (gsi, g, GSI_NEW_STMT);

  gimple_assign_set_rhs_with_ops (&gsi2, NOP_EXPR, urhs, NULL_TREE);
  update_stmt (stmt);

  gsi2 = gsi_after_labels (then_bb);
  if (flag_sanitize_undefined_trap_on_error)
    g = gimple_build_call (builtin_decl_explicit (BUILT_IN_TRAP), 0);
  else
    {
      tree data = ubsan_create_data ("__ubsan_invalid_value_data", &loc, NULL,
				     ubsan_type_descriptor (type), NULL_TREE);
      data = build_fold_addr_expr_loc (loc, data);
      enum built_in_function bcode
	= flag_sanitize_recover
	  ? BUILT_IN_UBSAN_HANDLE_LOAD_INVALID_VALUE
	  : BUILT_IN_UBSAN_HANDLE_LOAD_INVALID_VALUE_ABORT;
      tree fn = builtin_decl_explicit (bcode);

      tree val = force_gimple_operand_gsi (&gsi2, ubsan_encode_value (urhs),
					   true, NULL_TREE, true,
					   GSI_SAME_STMT);
      g = gimple_build_call (fn, 2, data, val);
    }
  gimple_set_location (g, loc);
  gsi_insert_before (&gsi2, g, GSI_SAME_STMT);
}
Exemple #7
0
void
ubsan_expand_null_ifn (gimple_stmt_iterator gsi)
{
  gimple stmt = gsi_stmt (gsi);
  location_t loc = gimple_location (stmt);
  gcc_assert (gimple_call_num_args (stmt) == 2);
  tree ptr = gimple_call_arg (stmt, 0);
  tree ckind = gimple_call_arg (stmt, 1);

  basic_block cur_bb = gsi_bb (gsi);

  /* Split the original block holding the pointer dereference.  */
  edge e = split_block (cur_bb, stmt);

  /* Get a hold on the 'condition block', the 'then block' and the
     'else block'.  */
  basic_block cond_bb = e->src;
  basic_block fallthru_bb = e->dest;
  basic_block then_bb = create_empty_bb (cond_bb);
  add_bb_to_loop (then_bb, cond_bb->loop_father);
  loops_state_set (LOOPS_NEED_FIXUP);

  /* Make an edge coming from the 'cond block' into the 'then block';
     this edge is unlikely taken, so set up the probability accordingly.  */
  e = make_edge (cond_bb, then_bb, EDGE_TRUE_VALUE);
  e->probability = PROB_VERY_UNLIKELY;

  /* Connect 'then block' with the 'else block'.  This is needed
     as the ubsan routines we call in the 'then block' are not noreturn.
     The 'then block' only has one outcoming edge.  */
  make_single_succ_edge (then_bb, fallthru_bb, EDGE_FALLTHRU);

  /* Set up the fallthrough basic block.  */
  e = find_edge (cond_bb, fallthru_bb);
  e->flags = EDGE_FALSE_VALUE;
  e->count = cond_bb->count;
  e->probability = REG_BR_PROB_BASE - PROB_VERY_UNLIKELY;

  /* Update dominance info for the newly created then_bb; note that
     fallthru_bb's dominance info has already been updated by
     split_bock.  */
  if (dom_info_available_p (CDI_DOMINATORS))
    set_immediate_dominator (CDI_DOMINATORS, then_bb, cond_bb);

  /* Put the ubsan builtin call into the newly created BB.  */
  gimple g;
  if (flag_sanitize_undefined_trap_on_error)
    g = gimple_build_call (builtin_decl_implicit (BUILT_IN_TRAP), 0);
  else
    {
      enum built_in_function bcode
	= flag_sanitize_recover
	  ? BUILT_IN_UBSAN_HANDLE_TYPE_MISMATCH
	  : BUILT_IN_UBSAN_HANDLE_TYPE_MISMATCH_ABORT;
      tree fn = builtin_decl_implicit (bcode);
      const struct ubsan_mismatch_data m
	= { build_zero_cst (pointer_sized_int_node), ckind };
      tree data
	= ubsan_create_data ("__ubsan_null_data", &loc, &m,
			     ubsan_type_descriptor (TREE_TYPE (ptr),
						    UBSAN_PRINT_POINTER),
			     NULL_TREE);
      data = build_fold_addr_expr_loc (loc, data);
      g = gimple_build_call (fn, 2, data,
			     build_zero_cst (pointer_sized_int_node));
    }
  gimple_set_location (g, loc);
  gimple_stmt_iterator gsi2 = gsi_start_bb (then_bb);
  gsi_insert_after (&gsi2, g, GSI_NEW_STMT);

  /* Unlink the UBSAN_NULLs vops before replacing it.  */
  unlink_stmt_vdef (stmt);

  g = gimple_build_cond (EQ_EXPR, ptr, build_int_cst (TREE_TYPE (ptr), 0),
			 NULL_TREE, NULL_TREE);
  gimple_set_location (g, loc);

  /* Replace the UBSAN_NULL with a GIMPLE_COND stmt.  */
  gsi_replace (&gsi, g, false);
}
static void
use_internal_fn (gcall *call)
{
  /* We'll be inserting another call with the same arguments after the
     lhs has been set, so prevent any possible coalescing failure from
     having both values live at once.  See PR 71020.  */
  replace_abnormal_ssa_names (call);

  unsigned nconds = 0;
  auto_vec<gimple *, 12> conds;
  if (can_test_argument_range (call))
    {
      gen_shrink_wrap_conditions (call, conds, &nconds);
      gcc_assert (nconds != 0);
    }
  else
    gcc_assert (edom_only_function (call));

  internal_fn ifn = replacement_internal_fn (call);
  gcc_assert (ifn != IFN_LAST);

  /* Construct the new call, with the same arguments as the original one.  */
  auto_vec <tree, 16> args;
  unsigned int nargs = gimple_call_num_args (call);
  for (unsigned int i = 0; i < nargs; ++i)
    args.safe_push (gimple_call_arg (call, i));
  gcall *new_call = gimple_build_call_internal_vec (ifn, args);
  gimple_set_location (new_call, gimple_location (call));
  gimple_call_set_nothrow (new_call, gimple_call_nothrow_p (call));

  /* Transfer the LHS to the new call.  */
  tree lhs = gimple_call_lhs (call);
  gimple_call_set_lhs (new_call, lhs);
  gimple_call_set_lhs (call, NULL_TREE);
  SSA_NAME_DEF_STMT (lhs) = new_call;

  /* Insert the new call.  */
  gimple_stmt_iterator gsi = gsi_for_stmt (call);
  gsi_insert_before (&gsi, new_call, GSI_SAME_STMT);

  if (nconds == 0)
    {
      /* Skip the call if LHS == LHS.  If we reach here, EDOM is the only
	 valid errno value and it is used iff the result is NaN.  */
      conds.quick_push (gimple_build_cond (EQ_EXPR, lhs, lhs,
					   NULL_TREE, NULL_TREE));
      nconds++;

      /* Try replacing the original call with a direct assignment to
	 errno, via an internal function.  */
      if (set_edom_supported_p () && !stmt_ends_bb_p (call))
	{
	  gimple_stmt_iterator gsi = gsi_for_stmt (call);
	  gcall *new_call = gimple_build_call_internal (IFN_SET_EDOM, 0);
	  gimple_set_vuse (new_call, gimple_vuse (call));
	  gimple_set_vdef (new_call, gimple_vdef (call));
	  SSA_NAME_DEF_STMT (gimple_vdef (new_call)) = new_call;
	  gimple_set_location (new_call, gimple_location (call));
	  gsi_replace (&gsi, new_call, false);
	  call = new_call;
	}
    }

  shrink_wrap_one_built_in_call_with_conds (call, conds, nconds);
}
Exemple #9
0
static gimple_seq
gimplify_cp_loop (tree cond, tree body, tree incr, bool cond_is_first)
{
  gimple top, entry, stmt;
  gimple_seq stmt_list, body_seq, incr_seq, exit_seq;
  tree cont_block, break_block;
  location_t stmt_locus;

  stmt_locus = input_location;
  stmt_list = NULL;
  body_seq = NULL;
  incr_seq = NULL;
  exit_seq = NULL;
  entry = NULL;

  break_block = begin_bc_block (bc_break);
  cont_block = begin_bc_block (bc_continue);

  /* If condition is zero don't generate a loop construct.  */
  if (cond && integer_zerop (cond))
    {
      top = NULL;
      if (cond_is_first)
	{
	  stmt = gimple_build_goto (get_bc_label (bc_break));
	  gimple_set_location (stmt, stmt_locus);
	  gimple_seq_add_stmt (&stmt_list, stmt);
	}
    }
  else
    {
      /* If we use a LOOP_EXPR here, we have to feed the whole thing
	 back through the main gimplifier to lower it.  Given that we
	 have to gimplify the loop body NOW so that we can resolve
	 break/continue stmts, seems easier to just expand to gotos.  */
      top = gimple_build_label (create_artificial_label ());

      /* If we have an exit condition, then we build an IF with gotos either
	 out of the loop, or to the top of it.  If there's no exit condition,
	 then we just build a jump back to the top.  */
      if (cond && !integer_nonzerop (cond))
	{
	  if (cond != error_mark_node)
	    { 
	      gimplify_expr (&cond, &exit_seq, NULL, is_gimple_val, fb_rvalue);
	      stmt = gimple_build_cond (NE_EXPR, cond,
					build_int_cst (TREE_TYPE (cond), 0),
					gimple_label_label (top),
					get_bc_label (bc_break));
	      gimple_seq_add_stmt (&exit_seq, stmt);
	    }

	  if (cond_is_first)
	    {
	      if (incr)
		{
		  entry = gimple_build_label (create_artificial_label ());
		  stmt = gimple_build_goto (gimple_label_label (entry));
		}
	      else
		stmt = gimple_build_goto (get_bc_label (bc_continue));
	      gimple_set_location (stmt, stmt_locus);
	      gimple_seq_add_stmt (&stmt_list, stmt);
	    }
	}
      else
	{
	  stmt = gimple_build_goto (gimple_label_label (top));
	  gimple_seq_add_stmt (&exit_seq, stmt);
	}
    }

  gimplify_stmt (&body, &body_seq);
  gimplify_stmt (&incr, &incr_seq);

  body_seq = finish_bc_block (bc_continue, cont_block, body_seq);

  gimple_seq_add_stmt (&stmt_list, top);
  gimple_seq_add_seq (&stmt_list, body_seq);
  gimple_seq_add_seq (&stmt_list, incr_seq);
  gimple_seq_add_stmt (&stmt_list, entry);
  gimple_seq_add_seq (&stmt_list, exit_seq);

  annotate_all_with_location (stmt_list, stmt_locus);

  return finish_bc_block (bc_break, break_block, stmt_list);
}