gcc/doc/gccint/gimple/tuple-specific-accessors/gimpleassign.rst

   1 ..
   2   Copyright 1988-2022 Free Software Foundation, Inc.
   3   This is part of the GCC manual.
   4   For copying conditions, see the copyright.rst file.
   5
   6 .. index:: GIMPLE_ASSIGN
   7
   8 GIMPLE_ASSIGN
   9 ^^^^^^^^^^^^^
  10
  11 .. function:: gassign *gimple_build_assign (tree lhs, tree rhs)
  12
  13   Build a ``GIMPLE_ASSIGN`` statement.  The left-hand side is an lvalue
  14   passed in lhs.  The right-hand side can be either a unary or
  15   binary tree expression.  The expression tree rhs will be
  16   flattened and its operands assigned to the corresponding operand
  17   slots in the new statement.  This function is useful when you
  18   already have a tree expression that you want to convert into a
  19   tuple.  However, try to avoid building expression trees for the
  20   sole purpose of calling this function.  If you already have the
  21   operands in separate trees, it is better to use
  22   ``gimple_build_assign`` with ``enum tree_code`` argument and separate
  23   arguments for each operand.
  24
  25 .. function:: gassign *gimple_build_assign (tree lhs, enum tree_code subcode, tree op1, tree op2, tree op3)
  26
  27   This function is similar to two operand ``gimple_build_assign``,
  28   but is used to build a ``GIMPLE_ASSIGN`` statement when the operands of the
  29   right-hand side of the assignment are already split into
  30   different operands.
  31
  32   The left-hand side is an lvalue passed in lhs.  Subcode is the
  33   ``tree_code`` for the right-hand side of the assignment.  Op1, op2 and op3
  34   are the operands.
  35
  36 .. function:: gassign *gimple_build_assign (tree lhs, enum tree_code subcode, tree op1, tree op2)
  37
  38   Like the above 5 operand ``gimple_build_assign``, but with the last
  39   argument ``NULL`` - this overload should not be used for
  40   ``GIMPLE_TERNARY_RHS`` assignments.
  41
  42 .. function:: gassign *gimple_build_assign (tree lhs, enum tree_code subcode, tree op1)
  43
  44   Like the above 4 operand ``gimple_build_assign``, but with the last
  45   argument ``NULL`` - this overload should be used only for
  46   ``GIMPLE_UNARY_RHS`` and ``GIMPLE_SINGLE_RHS`` assignments.
  47
  48 .. function:: gimple gimplify_assign (tree dst, tree src, gimple_seq *seq_p)
  49
  50   Build a new ``GIMPLE_ASSIGN`` tuple and append it to the end of
  51   ``*SEQ_P``.
  52
  53 ``DST`` / ``SRC`` are the destination and source respectively.  You can
  54 pass ungimplified trees in ``DST`` or ``SRC``, in which
  55 case they will be converted to a gimple operand if necessary.
  56
  57 This function returns the newly created ``GIMPLE_ASSIGN`` tuple.
  58
  59 .. function:: enum tree_code gimple_assign_rhs_code (gimple g)
  60
  61   Return the code of the expression computed on the ``RHS`` of
  62   assignment statement ``G``.
  63
  64 .. function:: enum gimple_rhs_class gimple_assign_rhs_class (gimple g)
  65
  66   Return the gimple rhs class of the code for the expression
  67   computed on the rhs of assignment statement ``G``.  This will never
  68   return ``GIMPLE_INVALID_RHS``.
  69
  70 .. function:: tree gimple_assign_lhs (gimple g)
  71
  72   Return the ``LHS`` of assignment statement ``G``.
  73
  74 .. function:: tree * gimple_assign_lhs_ptr (gimple g)
  75
  76   Return a pointer to the ``LHS`` of assignment statement ``G``.
  77
  78 .. function:: tree gimple_assign_rhs1 (gimple g)
  79
  80   Return the first operand on the ``RHS`` of assignment statement ``G``.
  81
  82 .. function:: tree * gimple_assign_rhs1_ptr (gimple g)
  83
  84   Return the address of the first operand on the ``RHS`` of assignment
  85   statement ``G``.
  86
  87 .. function:: tree gimple_assign_rhs2 (gimple g)
  88
  89   Return the second operand on the ``RHS`` of assignment statement ``G``.
  90
  91 .. function:: tree * gimple_assign_rhs2_ptr (gimple g)
  92
  93   Return the address of the second operand on the ``RHS`` of assignment
  94   statement ``G``.
  95
  96 .. function:: tree gimple_assign_rhs3 (gimple g)
  97
  98   Return the third operand on the ``RHS`` of assignment statement ``G``.
  99
 100 .. function:: tree * gimple_assign_rhs3_ptr (gimple g)
 101
 102   Return the address of the third operand on the ``RHS`` of assignment
 103   statement ``G``.
 104
 105 .. function:: void gimple_assign_set_lhs (gimple g, tree lhs)
 106
 107   Set ``LHS`` to be the ``LHS`` operand of assignment statement ``G``.
 108
 109 .. function:: void gimple_assign_set_rhs1 (gimple g, tree rhs)
 110
 111   Set ``RHS`` to be the first operand on the ``RHS`` of assignment
 112   statement ``G``.
 113
 114 .. function:: void gimple_assign_set_rhs2 (gimple g, tree rhs)
 115
 116   Set ``RHS`` to be the second operand on the ``RHS`` of assignment
 117   statement ``G``.
 118
 119 .. function:: void gimple_assign_set_rhs3 (gimple g, tree rhs)
 120
 121   Set ``RHS`` to be the third operand on the ``RHS`` of assignment
 122   statement ``G``.
 123
 124 .. function:: bool gimple_assign_cast_p (const_gimple s)
 125
 126   Return true if ``S`` is a type-cast assignment.