File : exp_code.ads
1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- E X P _ C O D E --
6 -- --
7 -- S p e c --
8 -- --
9 -- Copyright (C) 1996-2007, Free Software Foundation, Inc. --
10 -- --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
20 -- --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
23 -- --
24 ------------------------------------------------------------------------------
25
26 -- Processing for handling code statements
27
28 with Types; use Types;
29
30 with System; use System;
31 package Exp_Code is
32
33 procedure Expand_Asm_Call (N : Node_Id);
34 -- Expands a call to Asm into an equivalent N_Code_Statement node
35
36 -- The following routines provide an abstract interface to analyze
37 -- code statements, for use by Gigi processing for code statements.
38 -- Note that the implementations of these routines must not attempt
39 -- to expand tables that are frozen on entry to Gigi.
40
41 function Is_Asm_Volatile (N : Node_Id) return Boolean;
42 -- Given an N_Code_Statement node N, return True if Volatile=True is
43 -- specified, and False if Volatile=False is specified (or set by default).
44
45 function Asm_Template (N : Node_Id) return Node_Id;
46 -- Given an N_Code_Statement node N, returns string literal node for
47 -- template in call
48
49 procedure Clobber_Setup (N : Node_Id);
50 -- Given an N_Code_Statement node N, setup to process the clobber list
51 -- with subsequent calls to Clobber_Get_Next.
52
53 function Clobber_Get_Next return System.Address;
54 -- Can only be called after a previous call to Clobber_Setup. The
55 -- returned value is a pointer to a null terminated (C format) string
56 -- for the next register argument. Null_Address is returned when there
57 -- are no more arguments.
58
59 procedure Setup_Asm_Inputs (N : Node_Id);
60 -- Given an N_Code_Statement node N, setup to read list of Asm_Input
61 -- arguments. The protocol is to construct a loop as follows:
62 --
63 -- Setup_Asm_Inputs (N);
64 -- while Present (Asm_Input_Value)
65 -- body
66 -- Next_Asm_Input;
67 -- end loop;
68 --
69 -- where the loop body calls Asm_Input_Constraint or Asm_Input_Value to
70 -- obtain the constraint string or input value expression from the current
71 -- Asm_Input argument.
72
73 function Asm_Input_Constraint return Node_Id;
74 -- Called within a loop initialized by Setup_Asm_Inputs and controlled
75 -- by Next_Asm_Input as described above. Returns a string literal node
76 -- for the constraint component of the current Asm_Input_Parameter, or
77 -- Empty if there are no more Asm_Input parameters.
78
79 function Asm_Input_Value return Node_Id;
80 -- Called within a loop initialized by Setup_Asm_Inputs and controlled
81 -- by Next_Asm_Input as described above. Returns the expression node for
82 -- the value component of the current Asm_Input parameter, or Empty if
83 -- there are no more Asm_Input parameters, or Error if an error was
84 -- previously detected in the input parameters (note that the backend
85 -- need not worry about this case, since it won't be called if there
86 -- were any such serious errors detected).
87
88 procedure Next_Asm_Input;
89 -- Step to next Asm_Input parameter. It is an error to call this procedure
90 -- if there are no more available parameters (which is impossible if the
91 -- call appears in a loop as in the above example).
92
93 procedure Setup_Asm_Outputs (N : Node_Id);
94 -- Given an N_Code_Statement node N, setup to read list of Asm_Output
95 -- arguments. The protocol is to construct a loop as follows:
96 --
97 -- Setup_Asm_Outputs (N);
98 -- while Present (Asm_Output_Variable)
99 -- body
100 -- Next_Asm_Output;
101 -- end loop;
102 --
103 -- where the loop body calls Asm_Output_Constraint or Asm_Output_Variable
104 -- to obtain the constraint string or output variable name from the current
105 -- Asm_Output argument.
106
107 function Asm_Output_Constraint return Node_Id;
108 -- Called within a loop initialized by Setup_Asm_Outputs and controlled
109 -- by Next_Asm_Output as described above. Returns a string literal node
110 -- for the constraint component of the current Asm_Output_Parameter, or
111 -- Empty if there are no more Asm_Output parameters.
112
113 function Asm_Output_Variable return Node_Id;
114 -- Called within a loop initialized by Setup_Asm_Outputs and controlled by
115 -- Next_Asm_Output as described above. Returns the expression node for the
116 -- output variable component of the current Asm_Output parameter, or Empty
117 -- if there are no more Asm_Output parameters, or Error if an error was
118 -- previously detected in the input parameters (note that the backend need
119 -- not worry about this case, since it won't be called if there were any
120 -- such serious errors detected).
121
122 procedure Next_Asm_Output;
123 -- Step to next Asm_Output parameter. It is an error to call this procedure
124 -- if there are no more available parameters (which is impossible if the
125 -- call appears in a loop as in the above example).
126
127 end Exp_Code;