toolchain/gcc/patches/11.2.0/001-Revert-Cleanup-range-of-address-calculations.patch

   1 From: Felix Fietkau <nbd@nbd.name>
   2 Date: Tue, 16 Nov 2021 10:39:51 +0100
   3 Subject: [PATCH] Revert "Cleanup range of address calculations."
   4
   5 This reverts commit 47923622c663ffad8b14aa93706183290d4f6791.
   6 This commit is causing issues with offset of struct members.
   7
   8 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103255
   9 ---
  10  delete mode 100644 gcc/testsuite/gcc.dg/tree-ssa/pr78655.c
  11
  12 --- a/gcc/gimple-range.cc
  13 +++ b/gcc/gimple-range.cc
  14 @@ -431,9 +431,8 @@ gimple_ranger::range_of_range_op (irange
  15        m_cache.register_dependency (lhs, op2);
  16      }
  17
  18 -  if (gimple_code (s) == GIMPLE_ASSIGN
  19 -      && gimple_assign_rhs_code (s) == ADDR_EXPR)
  20 -    return range_of_address (r, s);
  21 +  if (range_of_non_trivial_assignment (r, s))
  22 +    return true;
  23
  24    if (range_of_expr (range1, op1, s))
  25      {
  26 @@ -447,84 +446,48 @@ gimple_ranger::range_of_range_op (irange
  27    return true;
  28  }
  29
  30 -// Calculate the range of an assignment containing an ADDR_EXPR.
  31 +// Calculate the range of a non-trivial assignment.  That is, is one
  32 +// inolving arithmetic on an SSA name (for example, an ADDR_EXPR).
  33  // Return the range in R.
  34 -// If a range cannot be calculated, set it to VARYING and return true.
  35 +//
  36 +// If a range cannot be calculated, return false.
  37
  38  bool
  39 -gimple_ranger::range_of_address (irange &r, gimple *stmt)
  40 +gimple_ranger::range_of_non_trivial_assignment (irange &r, gimple *stmt)
  41  {
  42 -  gcc_checking_assert (gimple_code (stmt) == GIMPLE_ASSIGN);
  43 -  gcc_checking_assert (gimple_assign_rhs_code (stmt) == ADDR_EXPR);
  44 +  if (gimple_code (stmt) != GIMPLE_ASSIGN)
  45 +    return false;
  46
  47 -  bool strict_overflow_p;
  48 -  tree expr = gimple_assign_rhs1 (stmt);
  49 -  poly_int64 bitsize, bitpos;
  50 -  tree offset;
  51 -  machine_mode mode;
  52 -  int unsignedp, reversep, volatilep;
  53 -  tree base = get_inner_reference (TREE_OPERAND (expr, 0), &bitsize,
  54 -                                  &bitpos, &offset, &mode, &unsignedp,
  55 -                                  &reversep, &volatilep);
  56 -
  57 -
  58 -  if (base != NULL_TREE
  59 -      && TREE_CODE (base) == MEM_REF
  60 -      && TREE_CODE (TREE_OPERAND (base, 0)) == SSA_NAME)
  61 +  tree base = gimple_range_base_of_assignment (stmt);
  62 +  if (base)
  63      {
  64 -      tree ssa = TREE_OPERAND (base, 0);
  65 -      gcc_checking_assert (irange::supports_type_p (TREE_TYPE (ssa)));
  66 -      range_of_expr (r, ssa, stmt);
  67 -      range_cast (r, TREE_TYPE (gimple_assign_rhs1 (stmt)));
  68 -
  69 -      poly_offset_int off = 0;
  70 -      bool off_cst = false;
  71 -      if (offset == NULL_TREE || TREE_CODE (offset) == INTEGER_CST)
  72 +      if (TREE_CODE (base) == MEM_REF)
  73         {
  74 -         off = mem_ref_offset (base);
  75 -         if (offset)
  76 -           off += poly_offset_int::from (wi::to_poly_wide (offset),
  77 -                                         SIGNED);
  78 -         off <<= LOG2_BITS_PER_UNIT;
  79 -         off += bitpos;
  80 -         off_cst = true;
  81 +         if (TREE_CODE (TREE_OPERAND (base, 0)) == SSA_NAME)
  82 +           {
  83 +             int_range_max range1;
  84 +             tree ssa = TREE_OPERAND (base, 0);
  85 +             if (range_of_expr (range1, ssa, stmt))
  86 +               {
  87 +                 tree type = TREE_TYPE (ssa);
  88 +                 range_operator *op = range_op_handler (POINTER_PLUS_EXPR,
  89 +                                                        type);
  90 +                 int_range<2> offset (TREE_OPERAND (base, 1),
  91 +                                      TREE_OPERAND (base, 1));
  92 +                 op->fold_range (r, type, range1, offset);
  93 +                 return true;
  94 +               }
  95 +           }
  96 +         return false;
  97         }
  98 -      /* If &X->a is equal to X, the range of X is the result.  */
  99 -      if (off_cst && known_eq (off, 0))
 100 -         return true;
 101 -      else if (flag_delete_null_pointer_checks
 102 -              && !TYPE_OVERFLOW_WRAPS (TREE_TYPE (expr)))
 103 -       {
 104 -        /* For -fdelete-null-pointer-checks -fno-wrapv-pointer we don't
 105 -        allow going from non-NULL pointer to NULL.  */
 106 -          if(!range_includes_zero_p (&r))
 107 -           return true;
 108 -       }
 109 -      /* If MEM_REF has a "positive" offset, consider it non-NULL
 110 -        always, for -fdelete-null-pointer-checks also "negative"
 111 -        ones.  Punt for unknown offsets (e.g. variable ones).  */
 112 -      if (!TYPE_OVERFLOW_WRAPS (TREE_TYPE (expr))
 113 -         && off_cst
 114 -         && known_ne (off, 0)
 115 -         && (flag_delete_null_pointer_checks || known_gt (off, 0)))
 116 +      if (gimple_assign_rhs_code (stmt) == ADDR_EXPR)
 117         {
 118 +         // Handle "= &a"  and return non-zero.
 119           r = range_nonzero (TREE_TYPE (gimple_assign_rhs1 (stmt)));
 120           return true;
 121         }
 122 -      r = int_range<2> (TREE_TYPE (gimple_assign_rhs1 (stmt)));
 123 -      return true;
 124 -    }
 125 -
 126 -  // Handle "= &a".
 127 -  if (tree_single_nonzero_warnv_p (expr, &strict_overflow_p))
 128 -    {
 129 -      r = range_nonzero (TREE_TYPE (gimple_assign_rhs1 (stmt)));
 130 -      return true;
 131      }
 132 -
 133 -  // Otherwise return varying.
 134 -  r = int_range<2> (TREE_TYPE (gimple_assign_rhs1 (stmt)));
 135 -  return true;
 136 +  return false;
 137  }
 138
 139  // Calculate a range for phi statement S and return it in R.
 140 --- a/gcc/gimple-range.h
 141 +++ b/gcc/gimple-range.h
 142 @@ -62,7 +62,7 @@ protected:
 143    ranger_cache m_cache;
 144  private:
 145    bool range_of_phi (irange &r, gphi *phi);
 146 -  bool range_of_address (irange &r, gimple *s);
 147 +  bool range_of_non_trivial_assignment (irange &r, gimple *s);
 148    bool range_of_builtin_call (irange &r, gcall *call);
 149    bool range_with_loop_info (irange &r, tree name);
 150    void range_of_ssa_name_with_loop_info (irange &, tree, class loop *,
 151 --- a/gcc/range-op.cc
 152 +++ b/gcc/range-op.cc
 153 @@ -3447,7 +3447,6 @@ pointer_table::pointer_table ()
 154    set (GT_EXPR, op_gt);
 155    set (GE_EXPR, op_ge);
 156    set (SSA_NAME, op_identity);
 157 -  set (INTEGER_CST, op_integer_cst);
 158    set (ADDR_EXPR, op_addr);
 159    set (NOP_EXPR, op_convert);
 160    set (CONVERT_EXPR, op_convert);