| blob | 47ea6df3f6a87ed66d186647cb7d80e38804bc62 |
1 /****************************************************************************
2 * *
3 * GNAT COMPILER COMPONENTS *
4 * *
5 * T R A N S *
6 * *
7 * C Implementation File *
8 * *
9 * Copyright (C) 1992-2005, 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 2, 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 COPYING. If not, write *
19 * to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, *
20 * MA 02111-1307, USA. *
21 * *
22 * GNAT was originally developed by the GNAT team at New York University. *
23 * Extensive contributions were provided by Ada Core Technologies Inc. *
24 * *
25 ****************************************************************************/
70 /* Current filename without path. */
73 /* If true, then gigi is being called on an analyzed but unexpanded
74 tree, and the only purpose of the call is to properly annotate
75 types with representation information. */
78 /* A structure used to gather together information about a statement group.
79 We use this to gather related statements, for example the "then" part
80 of a IF. In the case where it represents a lexical scope, we may also
81 have a BLOCK node corresponding to it and/or cleanups. */
88 };
92 /* List of unused struct stmt_group nodes. */
95 /* A structure used to record information on elaboration procedures
96 we've made and need to process.
98 ??? gnat_node should be Node_Id, but gengtype gets confused. */
104 };
108 /* Free list of TREE_LIST nodes used for stacks. */
111 /* List of TREE_LIST nodes representing a stack of exception pointer
112 variables. TREE_VALUE is the VAR_DECL that stores the address of
113 the raised exception. Nonzero means we are in an exception
114 handler. Not used in the zero-cost case. */
117 /* List of TREE_LIST nodes used to store the current elaboration procedure
118 decl. TREE_VALUE is the decl. */
121 /* Variable that stores a list of labels to be used as a goto target instead of
122 a return in some functions. See processing for N_Subprogram_Body. */
125 /* List of TREE_LIST nodes representing a stack of LOOP_STMT nodes.
126 TREE_VALUE of each entry is the label of the corresponding LOOP_STMT. */
129 /* List of TREE_LIST nodes representing labels for switch statements.
130 TREE_VALUE of each entry is the label at the end of the switch. */
133 /* Map GNAT tree codes to GCC tree codes for simple expressions. */
136 /* Current node being treated, in case abort called. */
137 Node_Id error_gnat_node;
168 \f
169 /* This is the main program of the back-end. It sets up all the table
170 structures and then generates code. */
172 void
180 Int gigi_operating_mode)
181 {
182 tree gnu_standard_long_long_float;
183 tree gnu_standard_exception_type;
203 /* If we are just annotating types, give VOID_TYPE zero sizes to avoid
204 errors. */
206 {
209 }
211 /* Save the type we made for integer as the type for Standard.Integer.
212 Then make the rest of the standard types. Note that some of these
213 may be subtypes. */
219 gnu_standard_long_long_float
221 gnu_standard_exception_type
226 /* Process any Pragma Ident for the main unit. */
227 #ifdef ASM_OUTPUT_IDENT
229 ASM_OUTPUT_IDENT
232 #endif
234 /* If we are using the GCC exception mechanism, let GCC know. */
241 /* Now see if we have any elaboration procedures to deal with. */
243 {
245 tree gnu_stmts;
247 /* Mark everything we have as not visited. */
250 /* Set the current function to be the elaboration procedure and gimplify
251 what we have. */
255 /* We should have a BIND_EXPR, but it may or may not have any statements
256 in it. If it doesn't have any, we have nothing to do. */
261 /* If there are no statements, there is no elaboration code. */
264 else
265 {
266 /* Otherwise, compile the function. Note that we'll be gimplifying
267 it twice, but that's fine for the nodes we use. */
270 }
271 }
272 }
273 \f
274 /* Perform initializations for this module. */
276 void
278 {
279 /* Initialize ourselves. */
283 /* Enable GNAT stack checking method if needed */
288 }
289 \f
290 /* Subroutine of gnat_to_gnu to translate gnat_node, an N_Identifier,
291 to a GCC tree, which is returned. GNU_RESULT_TYPE_P is a pointer to
292 where we should place the result type. */
294 static tree
296 {
297 tree gnu_result_type;
298 tree gnu_result;
301 /* If the Etype of this node does not equal the Etype of the Entity,
302 something is wrong with the entity map, probably in generic
303 instantiation. However, this does not apply to types. Since we sometime
304 have strange Ekind's, just do this test for objects. Also, if the Etype of
305 the Entity is private, the Etype of the N_Identifier is allowed to be the
306 full type and also we consider a packed array type to be the same as the
307 original type. Similarly, a class-wide type is equivalent to a subtype of
308 itself. Finally, if the types are Itypes, one may be a copy of the other,
309 which is also legal. */
332 /* If this is a reference to a deferred constant whose partial view is an
333 unconstrained private type, the proper type is on the full view of the
334 constant, not on the full view of the type, which may be unconstrained.
336 This may be a reference to a type, for example in the prefix of the
337 attribute Position, generated for dispatching code (see Make_DT in
338 exp_disp,adb). In that case we need the type itself, not is parent,
339 in particular if it is a derived type */
344 {
348 }
349 else
350 {
351 /* Expand the type of this identitier first, in case it is an enumeral
352 literal, which only get made when the type is expanded. There is no
353 order-of-elaboration issue here. We want to use the Actual_Subtype if
354 it has already been elaborated, otherwise the Etype. Avoid using
355 Actual_Subtype for packed arrays to simplify things. */
363 else
367 }
371 /* If we are in an exception handler, force this variable into memory to
372 ensure optimization does not remove stores that appear redundant but are
373 actually needed in case an exception occurs.
375 ??? Note that we need not do this if the variable is declared within the
376 handler, only if it is referenced in the handler and declared in an
377 enclosing block, but we have no way of testing that right now.
379 ??? Also, for now all we can do is make it volatile. But we only
380 do this for SJLJ. */
385 /* Some objects (such as parameters passed by reference, globals of
386 variable size, and renamed objects) actually represent the address
387 of the object. In that case, we must do the dereference. Likewise,
388 deal with parameters to foreign convention subprograms. Call fold
389 here since GNU_RESULT may be a CONST_DECL. */
394 {
396 tree initial;
400 gnu_result
403 gnu_result));
405 /* If the object is constant, we try to do the dereference directly
406 through the DECL_INITIAL. This is actually required in order to get
407 correct aliasing information for renamed objects that are components
408 of non-aliased aggregates, because the type of the renamed object and
409 that of the aggregate don't alias.
411 Note that we expect the initial value to have been stabilized.
412 If it contains e.g. a variable reference, we certainly don't want
413 to re-evaluate the variable each time the renaming is used.
415 Stabilization is currently not performed at the global level but
416 create_var_decl avoids setting DECL_INITIAL if the value is not
417 constant then, and we get to the pointer dereference below.
419 ??? Couldn't the aliasing issue show up again in this case ?
420 There is no obvious reason why not. */
423 /* Strip possible conversion to reference type. */
425 == NOP_EXPR
433 else
438 }
440 /* The GNAT tree has the type of a function as the type of its result. Also
441 use the type of the result if the Etype is a subtype which is nominally
442 unconstrained. But remove any padding from the resulting type. */
445 {
450 }
452 /* We always want to return the underlying INTEGER_CST for an enumeration
453 literal to avoid the need to call fold in lots of places. But don't do
454 this is the parent will be taking the address of this object. */
456 {
470 }
474 }
475 \f
476 /* Subroutine of gnat_to_gnu to process gnat_node, an N_Pragma. Return
477 any statements we generate. */
479 static tree
481 {
482 Node_Id gnat_temp;
485 /* Check for (and ignore) unrecognized pragma and do nothing if we are just
486 annotating types. */
491 {
493 /* Do nothing at top level: all such variables are already viewable. */
500 {
509 }
515 {
528 }
535 }
538 }
539 /* Subroutine of gnat_to_gnu to translate gnat_node, an N_Attribute,
540 to a GCC tree, which is returned. GNU_RESULT_TYPE_P is a pointer to
541 where we should place the result type. ATTRIBUTE is the attribute ID. */
543 static tree
545 {
547 tree gnu_result_type;
548 tree gnu_expr;
553 /* If the input is a NULL_EXPR, make a new one. */
555 {
559 }
562 {
565 /* These are just conversions until since representation clauses for
566 enumerations are handled in the front end. */
567 {
574 }
579 /* These just add or subject the constant 1. Representation clauses for
580 enumerations are handled in the front-end. */
585 {
587 gnu_expr
588 = emit_check
590 gnu_expr,
591 attribute == Attr_Pred
595 }
597 gnu_result
606 /* Conversions don't change something's address but can cause us to miss
607 the COMPONENT_REF case below, so strip them off. */
611 /* If we are taking 'Address of an unconstrained object, this is the
612 pointer to the underlying array. */
615 /* ... fall through ... */
621 gnu_result
628 /* For 'Code_Address, find an inner ADDR_EXPR and mark it so that we
629 don't try to build a trampoline. */
631 {
640 }
644 {
645 tree gnu_obj_type;
650 /* If this is an unconstrained array, we know the object must have been
651 allocated with the template in front of the object. So compute the
652 template address.*/
654 gnu_ptr
656 (TYPE_OBJECT_RECORD_TYPE
658 gnu_ptr);
663 {
666 tree gnu_byte_offset
673 }
676 }
685 /* Remove NOPS from gnu_expr and conversions from gnu_prefix.
686 We only use GNU_EXPR to see if a COMPONENT_REF was involved. */
689 ;
695 /* Replace an unconstrained array type with the type of the underlying
696 array. We can't do this with a call to maybe_unconstrained_array
697 since we may have a TYPE_DECL. For 'Max_Size_In_Storage_Elements,
698 use the record type that will be used to allocate the object and its
699 template. */
701 {
705 }
707 /* If we're looking for the size of a field, return the field size.
708 Otherwise, if the prefix is an object, or if 'Object_Size or
709 'Max_Size_In_Storage_Elements has been specified, the result is the
710 GCC size of the type. Otherwise, the result is the RM_Size of the
711 type. */
717 {
718 /* If this is a padded type, the GCC size isn't relevant to the
719 programmer. Normally, what we want is the RM_Size, which was set
720 from the specified size, but if it was not set, we want the size
721 of the relevant field. Using the MAX of those two produces the
722 right result in all case. Don't use the size of the field if it's
723 a self-referential type, since that's never what's wanted. */
727 {
731 gnu_result
734 }
735 else
737 }
738 else
743 /* Deal with a self-referential size by returning the maximum size for a
744 type and by qualifying the size with the object for 'Size of an
745 object. */
747 {
750 gnu_expr);
751 else
753 }
755 /* If the type contains a template, subtract its size. */
763 /* Always perform division using unsigned arithmetic as the size cannot
764 be negative, but may be an overflowed positive value. This provides
765 correct results for sizes up to 512 MB.
767 ??? Size should be calculated in storage elements directly. */
788 else
798 {
805 else
806 gnu_result
807 = build_binary_op
809 build_binary_op
821 }
823 /* ... fall through ... */
826 {
831 /* Make sure any implicit dereference gets done. */
839 {
841 tree gnu_type_temp;
847 ;
850 }
857 gnu_result
860 gnu_result
862 else
863 /* 'Length or 'Range_Length. */
864 {
865 tree gnu_compute_type
869 gnu_result
870 = build_binary_op
872 build_binary_op
874 build_binary_op
877 TYPE_MAX_VALUE
880 TYPE_MIN_VALUE
884 }
886 /* If this has a PLACEHOLDER_EXPR, qualify it by the object we are
887 handling. Note that these attributes could not have been used on
888 an unconstrained array type. */
890 gnu_prefix);
892 }
899 {
900 HOST_WIDE_INT bitsize;
901 HOST_WIDE_INT bitpos;
902 tree gnu_offset;
903 tree gnu_field_bitpos;
904 tree gnu_field_offset;
905 tree gnu_inner;
913 /* We can have 'Bit on any object, but if it isn't a COMPONENT_REF,
914 the result is 0. Don't allow 'Bit on a bare component, though. */
918 {
921 }
923 else
932 {
940 {
941 gnu_field_bitpos
944 gnu_field_offset
947 }
948 }
950 {
953 }
954 else
955 {
958 }
961 {
976 bitsize_one_node);
982 }
984 /* If this has a PLACEHOLDER_EXPR, qualify it by the object
985 we are handling. */
988 }
992 {
1000 }
1028 /* Note this size cannot be self-referential. */
1035 /* This is just a zero cast to the pointer type for
1036 our prefix and dereferenced. */
1038 gnu_result
1041 integer_zero_node));
1046 {
1053 {
1058 ;
1059 }
1067 && (DECL_BY_COMPONENT_PTR_P
1071 }
1075 /* Say we have an unimplemented attribute. Then set the value to be
1076 returned to be a zero and hope that's something we can convert to the
1077 type of this attribute. */
1082 }
1084 /* If this is an attribute where the prefix was unused, force a use of it if
1085 it has a side-effect. But don't do it if the prefix is just an entity
1086 name. However, if an access check is needed, we must do it. See second
1087 example in AARM 11.6(5.e). */
1095 }
1096 \f
1097 /* Subroutine of gnat_to_gnu to translate gnat_node, an N_Case_Statement,
1098 to a GCC tree, which is returned. */
1100 static tree
1102 {
1103 tree gnu_result;
1104 tree gnu_expr;
1105 Node_Id gnat_when;
1110 /* The range of values in a case statement is determined by the rules in
1111 RM 5.4(7-9). In almost all cases, this range is represented by the Etype
1112 of the expression. One exception arises in the case of a simple name that
1113 is parenthesized. This still has the Etype of the name, but since it is
1114 not a name, para 7 does not apply, and we need to go to the base type.
1115 This is the only case where parenthesization affects the dynamic
1116 semantics (i.e. the range of possible values at runtime that is covered
1117 by the others alternative.
1119 Another exception is if the subtype of the expression is non-static. In
1120 that case, we also have to use the base type. */
1126 /* We build a SWITCH_EXPR that contains the code with interspersed
1127 CASE_LABEL_EXPRs for each label. */
1134 {
1135 Node_Id gnat_choice;
1137 /* First compile all the different case choices for the current WHEN
1138 alternative. */
1141 {
1145 {
1160 /* This represents either a subtype range or a static value of
1161 some kind; Ekind says which. If a static value, fall through
1162 to the next case. */
1164 {
1170 }
1172 /* ... fall through ... */
1184 }
1189 gnat_choice);
1190 }
1192 /* Push a binding level here in case variables are declared since we want
1193 them to be local to this set of statements instead of the block
1194 containing the Case statement. */
1198 }
1200 /* Now emit a definition of the label all the cases branched to. */
1208 }
1209 \f
1210 /* Subroutine of gnat_to_gnu to translate gnat_node, an N_Loop_Statement,
1211 to a GCC tree, which is returned. */
1213 static tree
1215 {
1216 /* ??? It would be nice to use "build" here, but there's no build5. */
1222 tree gnu_result;
1229 /* Save the end label of this LOOP_STMT in a stack so that the corresponding
1230 N_Exit_Statement can find it. */
1234 /* Set the condition that under which the loop should continue.
1235 For "LOOP .... END LOOP;" the condition is always true. */
1237 ;
1238 /* The case "WHILE condition LOOP ..... END LOOP;" */
1242 else
1243 {
1244 /* We have an iteration scheme. */
1259 /* We know the loop variable will not overflow if GNU_LAST is a constant
1260 and is not equal to GNU_LIMIT. If it might overflow, we have to move
1261 the limit test to the end of the loop. In that case, we have to test
1262 for an empty loop outside the loop. */
1266 {
1267 gnu_cond_expr
1273 }
1275 /* Open a new nesting level that will surround the loop to declare the
1276 loop index variable. */
1280 /* Declare the loop index and set it to its initial value. */
1285 /* The loop variable might be a padded type, so use `convert' to get a
1286 reference to the inner variable if so. */
1289 /* Set either the top or bottom exit condition as appropriate depending
1290 on whether or not we know an overflow cannot occur. */
1295 else
1304 gnu_loop_var,
1306 integer_one_node));
1308 gnat_iter_scheme);
1309 }
1311 /* If the loop was named, have the name point to this loop. In this case,
1312 the association is not a ..._DECL node, but the end label from this
1313 LOOP_STMT. */
1318 /* Make the loop body into its own block, so any allocated storage will be
1319 released every iteration. This is needed for stack allocation. */
1323 /* If we declared a variable, then we are in a statement group for that
1324 declaration. Add the LOOP_STMT to it and make that the "loop". */
1326 {
1330 }
1332 /* If we have an outer COND_EXPR, that's our result and this loop is its
1333 "true" statement. Otherwise, the result is the LOOP_STMT. */
1335 {
1339 }
1340 else
1346 }
1347 \f
1348 /* Subroutine of gnat_to_gnu to process gnat_node, an N_Subprogram_Body. We
1349 don't return anything. */
1351 static void
1353 {
1354 /* Save debug output mode in case it is reset. */
1357 /* Definining identifier of a parameter to the subprogram. */
1358 Entity_Id gnat_param;
1359 /* The defining identifier for the subprogram body. Note that if a
1360 specification has appeared before for this body, then the identifier
1361 occurring in that specification will also be a defining identifier and all
1362 the calls to this subprogram will point to that specification. */
1363 Entity_Id gnat_subprog_id
1366 /* The FUNCTION_DECL node corresponding to the subprogram spec. */
1367 tree gnu_subprog_decl;
1368 /* The FUNCTION_TYPE node corresponding to the subprogram spec. */
1369 tree gnu_subprog_type;
1370 tree gnu_cico_list;
1371 tree gnu_result;
1373 /* If this is a generic object or if it has been eliminated,
1374 ignore it. */
1380 /* If debug information is suppressed for the subprogram, turn debug
1381 mode off for the duration of processing. */
1383 {
1386 }
1388 /* If this subprogram acts as its own spec, define it. Otherwise, just get
1389 the already-elaborated tree node. However, if this subprogram had its
1390 elaboration deferred, we will already have made a tree node for it. So
1391 treat it as not being defined in that case. Such a subprogram cannot
1392 have an address clause or a freeze node, so this test is safe, though it
1393 does disable some otherwise-useful error checking. */
1394 gnu_subprog_decl
1401 /* Set the line number in the decl to correspond to that of the body so that
1402 the line number notes are written
1403 correctly. */
1409 /* If there are OUT parameters, we need to ensure that the return statement
1410 properly copies them out. We do this by making a new block and converting
1411 any inner return into a goto to a label at the end of the block. */
1415 /* Get a tree corresponding to the code for the subprogram. */
1419 /* See if there are any parameters for which we don't yet have GCC entities.
1420 These must be for OUT parameters for which we will be making VAR_DECL
1421 nodes here. Fill them in to TYPE_CI_CO_LIST, which must contain the empty
1422 entry as well. We can match up the entries because TYPE_CI_CO_LIST is in
1423 the order of the parameters. */
1428 {
1429 /* Skip any entries that have been already filled in; they must
1430 correspond to IN OUT parameters. */
1433 ;
1435 /* Do any needed references for padded types. */
1439 }
1443 /* Generate the code of the subprogram itself. A return statement will be
1444 present and any OUT parameters will be handled there. */
1449 /* If we made a special return label, we need to make a block that contains
1450 the definition of that label and the copying to the return value. That
1451 block first contains the function, then the label and copy statement. */
1453 {
1454 tree gnu_retval;
1465 else
1467 gnu_cico_list);
1472 add_stmt_with_node
1474 gnat_node);
1477 }
1481 /* Initialize the information node for the function and set the
1482 end location. */
1484 Sloc_to_locus
1492 /* Disconnect the trees for parameters that we made variables for from the
1493 GNAT entities since these are unusable after we end the function. */
1503 }
1504 \f
1505 /* Subroutine of gnat_to_gnu to translate gnat_node, either an N_Function_Call
1506 or an N_Procedure_Call_Statement, to a GCC tree, which is returned.
1507 GNU_RESULT_TYPE_P is a pointer to where we should place the result type.
1508 If GNU_TARGET is non-null, this must be a function call and the result
1509 of the call is to be placed into that object. */
1511 static tree
1513 {
1514 tree gnu_result;
1515 /* The GCC node corresponding to the GNAT subprogram name. This can either
1516 be a FUNCTION_DECL node if we are dealing with a standard subprogram call,
1517 or an indirect reference expression (an INDIRECT_REF node) pointing to a
1518 subprogram. */
1520 /* The FUNCTION_TYPE node giving the GCC type of the subprogram. */
1523 gnu_subprog_node);
1524 Entity_Id gnat_formal;
1525 Node_Id gnat_actual;
1530 tree gnu_subprog_call;
1533 {
1540 }
1544 /* If we are calling a stubbed function, make this into a raise of
1545 Program_Error. Elaborate all our args first. */
1548 {
1555 {
1559 }
1560 else
1562 }
1564 /* If we are calling by supplying a pointer to a target, set up that
1565 pointer as the first argument. Use GNU_TARGET if one was passed;
1566 otherwise, make a target by building a variable of the maximum size
1567 of the type. */
1569 {
1570 tree gnu_real_ret_type
1574 {
1575 tree gnu_obj_type
1583 }
1585 gnu_actual_list
1589 gnu_target,
1591 NULL_TREE);
1593 }
1595 /* The only way we can be making a call via an access type is if Name is an
1596 explicit dereference. In that case, get the list of formal args from the
1597 type the access type is pointing to. Otherwise, get the formals from
1598 entity being called. */
1602 /* Assume here that this must be 'Elab_Body or 'Elab_Spec. */
1604 else
1607 /* Create the list of the actual parameters as GCC expects it, namely a chain
1608 of TREE_LIST nodes in which the TREE_VALUE field of each node is a
1609 parameter-expression and the TREE_PURPOSE field is null. Skip OUT
1610 parameters not passed by reference and don't need to be copied in. */
1615 {
1616 tree gnu_formal
1619 /* We treat a conversion between aggregate types as if it is an
1620 unchecked conversion. */
1621 bool unchecked_convert_p
1625 Node_Id gnat_name = (unchecked_convert_p
1629 tree gnu_actual;
1630 tree gnu_formal_type;
1632 /* If it's possible we may need to use this expression twice, make sure
1633 than any side-effects are handled via SAVE_EXPRs. Likewise if we need
1634 to force side-effects before the call.
1636 ??? This is more conservative than we need since we don't need to do
1637 this for pass-by-ref with no conversion. If we are passing a
1638 non-addressable Out or In Out parameter by reference, pass the address
1639 of a copy and set up to copy back out after the call. */
1641 {
1644 && gnu_formal
1649 {
1651 tree gnu_temp;
1653 /* Remove any unpadding on the actual and make a copy. But if
1654 the actual is a justified modular type, first convert
1655 to it. */
1659 && (TYPE_IS_PADDING_P
1668 /* Since we're going to take the address of the SAVE_EXPR, we
1669 don't want it to be marked as unchanging. So set
1670 TREE_ADDRESSABLE. */
1673 {
1676 }
1678 /* Set up to move the copy back to the original. */
1684 /* Account for next statement just below. */
1686 }
1687 }
1689 /* If this was a procedure call, we may not have removed any padding.
1690 So do it here for the part we will use as an input, if any. */
1696 gnu_actual);
1698 /* Unless this is an In parameter, we must remove any LJM building
1699 from GNU_NAME. */
1705 gnu_name);
1708 && !unchecked_convert_p
1712 /* Do any needed conversions. We need only check for unchecked
1713 conversion since normal conversions will be handled by just
1714 converting to the formal type. */
1716 {
1717 gnu_actual
1719 gnu_actual,
1724 /* One we've done the unchecked conversion, we still must ensure that
1725 the object is in range of the formal's type. */
1730 }
1732 /* We may have suppressed a conversion to the Etype of the actual since
1733 the parent is a procedure call. So add the conversion here. */
1735 gnu_actual);
1737 /* If we have not saved a GCC object for the formal, it means it is an
1738 OUT parameter not passed by reference and that does not need to be
1739 copied in. Otherwise, look at the PARM_DECL to see if it is passed by
1740 reference. */
1743 {
1745 {
1748 /* If we have a padded type, be sure we've removed padding. */
1753 gnu_actual);
1755 /* If we have the constructed subtype of an aliased object
1756 with an unconstrained nominal subtype, the type of the
1757 actual includes the template, although it is formally
1758 constrained. So we need to convert it back to the real
1759 constructed subtype to retrieve the constrained part
1760 and takes its address. */
1767 gnu_actual);
1768 }
1770 /* Otherwise, if we have a non-addressable COMPONENT_REF of a
1771 variable-size type see if it's doing a unpadding operation. If
1772 so, remove that operation since we have no way of allocating the
1773 required temporary. */
1783 /* The symmetry of the paths to the type of an entity is broken here
1784 since arguments don't know that they will be passed by ref. */
1787 }
1790 {
1797 {
1800 }
1802 /* Take the address of the object and convert to the proper pointer
1803 type. We'd like to actually compute the address of the beginning
1804 of the array using an ADDR_EXPR of an ARRAY_REF, but there's a
1805 possibility that the ARRAY_REF might return a constant and we'd be
1806 getting the wrong address. Neither approach is exactly correct,
1807 but this is the most likely to work in all cases. */
1810 gnu_actual));
1811 }
1814 {
1815 /* If arg is 'Null_Parameter, pass zero descriptor. */
1820 integer_zero_node);
1821 else
1824 gnat_formal));
1825 }
1826 else
1827 {
1836 /* If this is 'Null_Parameter, pass a zero even though we are
1837 dereferencing it. */
1842 BITS_PER_WORD))
1843 gnu_actual
1848 integer_zero_node),
1850 else
1852 }
1855 }
1859 NULL_TREE);
1861 /* If we return by passing a target, we emit the call and return the target
1862 as our result. */
1864 {
1866 *gnu_result_type_p
1869 }
1871 /* If it is a function call, the result is the call expression unless
1872 a target is specified, in which case we copy the result into the target
1873 and return the assignment statement. */
1875 {
1878 /* If the function returns an unconstrained array or by reference,
1879 we have to de-dereference the pointer. */
1887 else
1891 }
1893 /* If this is the case where the GNAT tree contains a procedure call
1894 but the Ada procedure has copy in copy out parameters, the special
1895 parameter passing mechanism must be used. */
1897 {
1898 /* List of FIELD_DECLs associated with the PARM_DECLs of the copy
1899 in copy out parameters. */
1904 {
1905 tree gnu_name;
1910 /* If any of the names had side-effects, ensure they are all
1911 evaluated before the call. */
1917 }
1921 else
1928 /* If we are dealing with a copy in copy out parameter, we must
1929 retrieve its value from the record returned in the call. */
1935 || (DECL_BY_DESCRIPTOR_P
1938 {
1939 /* Get the value to assign to this OUT or IN OUT parameter. It is
1940 either the result of the function if there is only a single such
1941 parameter or the appropriate field from the record returned. */
1942 tree gnu_result
1949 /* If the actual is a conversion, get the inner expression, which
1950 will be the real destination, and convert the result to the
1951 type of the actual parameter. */
1952 tree gnu_actual
1955 /* If the result is a padded type, remove the padding. */
1960 gnu_result);
1962 /* If the result is a type conversion, do it. */
1964 gnu_result
1965 = convert_with_check
1973 gnu_result,
1975 else
1976 {
1984 }
1992 }
1993 }
1994 else
1995 {
1998 }
2002 }
2003 \f
2004 /* Subroutine of gnat_to_gnu to translate gnat_node, an
2005 N_Handled_Sequence_Of_Statements, to a GCC tree, which is returned. */
2007 static tree
2009 {
2012 /* If just annotating, ignore all EH and cleanups. */
2016 bool setjmp_longjmp
2022 tree gnu_result;
2023 tree gnu_expr;
2024 Node_Id gnat_temp;
2026 /* The GCC exception handling mechanism can handle both ZCX and SJLJ schemes
2027 and we have our own SJLJ mechanism. To call the GCC mechanism, we call
2028 add_cleanup, and when we leave the binding, end_stmt_group will create
2029 the TRY_FINALLY_EXPR.
2031 ??? The region level calls down there have been specifically put in place
2032 for a ZCX context and currently the order in which things are emitted
2033 (region/handlers) is different from the SJLJ case. Instead of putting
2034 other calls with different conditions at other places for the SJLJ case,
2035 it seems cleaner to reorder things for the SJLJ case and generalize the
2036 condition to make it not ZCX specific.
2038 If there are any exceptions or cleanup processing involved, we need an
2039 outer statement group (for Setjmp_Longjmp) and binding level. */
2041 {
2044 }
2046 /* If we are to call a function when exiting this block add a cleanup
2047 to the binding level we made above. */
2051 /* If using setjmp_longjmp, make the variables for the setjmp buffer and save
2052 area for address of previous buffer. Do this first since we need to have
2053 the setjmp buf known for any decls in this block. */
2055 {
2060 gnat_node);
2068 /* When we exit this block, restore the saved value. */
2070 }
2072 /* Now build the tree for the declarations and statements inside this block.
2073 If this is SJLJ, set our jmp_buf as the current buffer. */
2079 gnu_jmpbuf_decl)));
2085 /* Generate code for each statement in the block. */
2093 /* Now generate code for the two exception models, if either is relevant for
2094 this block. */
2096 {
2098 tree gnu_handler;
2100 /* Make a binding level for the exception handling declarations and code
2101 and set up gnu_except_ptr_stack for the handlers to use. */
2107 NULL_TREE,
2112 /* Generate code for each handler. The N_Exception_Handler case does the
2113 real work and returns a COND_EXPR for each handler, which we chain
2114 together here. */
2117 {
2120 /* If this is the first one, set it as the outer one. Otherwise,
2121 point the "else" part of the previous handler to us. Then point
2122 to our "else" part. */
2125 else
2129 }
2131 /* If none of the exception handlers did anything, re-raise but do not
2132 defer abortion. */
2139 else
2142 /* End the binding level dedicated to the exception handlers and get the
2143 whole statement group. */
2148 /* If the setjmp returns 1, we restore our incoming longjmp value and
2149 then check the handlers. */
2152 gnu_jmpsave_decl),
2153 gnat_node);
2157 /* This block is now "if (setjmp) ... <handlers> else <block>". */
2159 (build_call_1_expr
2162 gnu_jmpbuf_decl))),
2164 }
2166 {
2167 tree gnu_handlers;
2169 /* First make a block containing the handlers. */
2177 /* Now make the TRY_CATCH_EXPR for the block. */
2180 }
2181 else
2184 /* Now close our outer block, if we had to make one. */
2186 {
2190 }
2193 }
2194 \f
2195 /* Subroutine of gnat_to_gnu to translate gnat_node, an N_Exception_Handler,
2196 to a GCC tree, which is returned. This is the variant for Setjmp_Longjmp
2197 exception handling. */
2199 static tree
2201 {
2202 /* Unless this is "Others" or the special "Non-Ada" exception for Ada, make
2203 an "if" statement to select the proper exceptions. For "Others", exclude
2204 exceptions where Handled_By_Others is nonzero unless the All_Others flag
2205 is set. For "Non-ada", accept an exception if "Lang" is 'V'. */
2208 Node_Id gnat_temp;
2212 {
2213 tree this_choice;
2216 {
2219 else
2220 this_choice
2221 = build_binary_op
2223 convert
2225 build_component_ref
2226 (build_unary_op
2231 integer_zero_node);
2232 }
2236 {
2238 tree gnu_expr;
2240 /* Exception may be a renaming. Recover original exception which is
2241 the one elaborated and registered. */
2247 this_choice
2248 = build_binary_op
2253 /* If this is the distinguished exception "Non_Ada_Error" (and we are
2254 in VMS mode), also allow a non-Ada exception (a VMS condition) t
2255 match. */
2257 {
2258 tree gnu_comp
2259 = build_component_ref
2264 this_choice
2265 = build_binary_op
2269 this_choice);
2270 }
2271 }
2272 else
2277 }
2280 }
2281 \f
2282 /* Subroutine of gnat_to_gnu to translate gnat_node, an N_Exception_Handler,
2283 to a GCC tree, which is returned. This is the variant for ZCX. */
2285 static tree
2287 {
2289 tree gnu_expr;
2290 tree gnu_etype;
2291 tree gnu_current_exc_ptr;
2292 tree gnu_incoming_exc_ptr;
2293 Node_Id gnat_temp;
2295 /* We build a TREE_LIST of nodes representing what exception types this
2296 handler can catch, with special cases for others and all others cases.
2298 Each exception type is actually identified by a pointer to the exception
2299 id, or to a dummy object for "others" and "all others".
2301 Care should be taken to ensure that the control flow impact of "others"
2302 and "all others" is known to GCC. lang_eh_type_covers is doing the trick
2303 currently. */
2306 {
2308 {
2309 tree gnu_expr
2312 gnu_etype
2314 }
2317 {
2320 /* Exception may be a renaming. Recover original exception which is
2321 the one elaborated and registered. */
2328 /* The Non_Ada_Error case for VMS exceptions is handled
2329 by the personality routine. */
2330 }
2331 else
2334 /* The GCC interface expects NULL to be passed for catch all handlers, so
2335 it would be quite tempting to set gnu_etypes_list to NULL if gnu_etype
2336 is integer_zero_node. It would not work, however, because GCC's
2337 notion of "catch all" is stronger than our notion of "others". Until
2338 we correctly use the cleanup interface as well, doing that would
2339 prevent the "all others" handlers from beeing seen, because nothing
2340 can be caught beyond a catch all from GCC's point of view. */
2342 }
2347 /* Expand a call to the begin_handler hook at the beginning of the handler,
2348 and arrange for a call to the end_handler hook to occur on every possible
2349 exit path.
2351 The hooks expect a pointer to the low level occurrence. This is required
2352 for our stack management scheme because a raise inside the handler pushes
2353 a new occurrence on top of the stack, which means that this top does not
2354 necessarily match the occurrence this handler was dealing with.
2356 The EXC_PTR_EXPR object references the exception occurrence being
2357 propagated. Upon handler entry, this is the exception for which the
2358 handler is triggered. This might not be the case upon handler exit,
2359 however, as we might have a new occurrence propagated by the handler's
2360 body, and the end_handler hook called as a cleanup in this context.
2362 We use a local variable to retrieve the incoming value at handler entry
2363 time, and reuse it to feed the end_handler hook's argument at exit. */
2368 gnat_node);
2371 gnu_incoming_exc_ptr),
2372 gnat_node);
2379 }
2380 \f
2381 /* Subroutine of gnat_to_gnu to generate code for an N_Compilation unit. */
2383 static void
2385 {
2386 /* Make the decl for the elaboration procedure. */
2391 tree gnu_elab_proc_decl
2392 = create_subprog_decl
2396 gnat_unit_entity);
2406 /* For a body, first process the spec if there is one. */
2415 {
2422 }
2428 /* Process any pragmas and actions following the unit. */
2432 /* Save away what we've made so far and record this potential elaboration
2433 procedure. */
2443 /* Generate elaboration code for this unit, if necessary, and say whether
2444 we did or not. */
2446 }
2447 \f
2448 /* This function is the driver of the GNAT to GCC tree transformation
2449 process. It is the entry point of the tree transformer. GNAT_NODE is the
2450 root of some GNAT tree. Return the root of the corresponding GCC tree.
2451 If this is an expression, return the GCC equivalent of the expression. If
2452 it is a statement, return the statement. In the case when called for a
2453 statement, it may also add statements to the current statement group, in
2454 which case anything it returns is to be interpreted as occuring after
2455 anything `it already added. */
2457 tree
2459 {
2463 tree gnu_expr;
2465 Node_Id gnat_temp;
2467 /* Save node number for error message and set location information. */
2475 /* If this node is a non-static subexpression and we are only
2476 annotating types, make this into a NULL_EXPR. */
2484 /* If this is a Statement and we are at top level, it must be part of
2485 the elaboration procedure, so mark us as being in that procedure
2486 and push our context. */
2498 {
2503 }
2506 {
2507 /********************************/
2508 /* Chapter 2: Lexical Elements: */
2509 /********************************/
2519 {
2520 tree gnu_type;
2522 /* Get the type of the result, looking inside any padding and
2523 justified modular types. Then get the value in that type. */
2532 /* If the result overflows (meaning it doesn't fit in its base type),
2533 abort. We would like to check that the value is within the range
2534 of the subtype, but that causes problems with subtypes whose usage
2535 will raise Constraint_Error and with biased representation, so
2536 we don't. */
2538 }
2542 /* If a Entity is present, it means that this was one of the
2543 literals in a user-defined character type. In that case,
2544 just return the value in the CONST_DECL. Otherwise, use the
2545 character code. In that case, the base type should be an
2546 INTEGER_TYPE, but we won't bother checking for that. */
2550 else
2551 gnu_result
2552 = force_fit_type
2553 (build_int_cst
2559 /* If this is of a fixed-point type, the value we want is the
2560 value of the corresponding integer. */
2562 {
2565 gnu_result_type);
2567 }
2569 /* We should never see a Vax_Float type literal, since the front end
2570 is supposed to transform these using appropriate conversions */
2574 else
2575 {
2580 /* If the real value is zero, so is the result. Otherwise,
2581 convert it to a machine number if it isn't already. That
2582 forces BASE to 0 or 2 and simplifies the rest of our logic. */
2585 else
2586 {
2588 ur_realval
2592 gnu_result
2595 /* If we have a base of zero, divide by the denominator.
2596 Otherwise, the base must be 2 and we scale the value, which
2597 we know can fit in the mantissa of the type (hence the use
2598 of that type above). */
2600 gnu_result
2603 gnu_result,
2605 gnu_result_type));
2606 else
2607 {
2608 REAL_VALUE_TYPE tmp;
2614 }
2615 }
2617 /* Now see if we need to negate the result. Do it this way to
2618 properly handle -0. */
2620 gnu_result
2622 gnu_result);
2623 }
2630 {
2636 /* Build the string with the characters in the literal. Note
2637 that Ada strings are 1-origin. */
2641 /* Put a null at the end of the string in case it's in a context
2642 where GCC will want to treat it as a C string. */
2647 /* Strings in GCC don't normally have types, but we want
2648 this to not be converted to the array type. */
2650 }
2651 else
2652 {
2653 /* Build a list consisting of each character, then make
2654 the aggregate. */
2662 {
2663 gnu_list
2668 gnu_list);
2672 }
2674 gnu_result
2676 }
2683 /**************************************/
2684 /* Chapter 3: Declarations and Types: */
2685 /**************************************/
2702 /* If we are just annotating types and this object has an unconstrained
2703 or task type, don't elaborate it. */
2714 && (!type_annotate_only
2716 {
2721 /* If this object has its elaboration delayed, we must force
2722 evaluation of GNU_EXPR right now and save it for when the object
2723 is frozen. */
2725 {
2728 gnu_expr
2733 else
2737 }
2738 }
2739 else
2752 /* Don't do anything if this renaming is handled by the front end or if
2753 we are just annotating types and this object has a composite or task
2754 type, don't elaborate it. We return the result in case it has any
2755 SAVE_EXPRs in it that need to be evaluated here. */
2757 && ! (type_annotate_only
2761 gnu_result
2764 else
2777 /* These are fully handled in the front end. */
2781 /*************************************/
2782 /* Chapter 4: Names and Expressions: */
2783 /*************************************/
2792 {
2794 tree gnu_type;
2802 /* If we got a padded type, remove it too. */
2805 gnu_array_object
2807 gnu_array_object);
2811 /* First compute the number of dimensions of the array, then
2812 fill the expression array, the order depending on whether
2813 this is a Convention_Fortran array or not. */
2818 ;
2827 else
2835 {
2841 gnu_expr
2842 = emit_index_check
2849 }
2850 }
2856 {
2857 tree gnu_type;
2863 /* Do any implicit dereferences of the prefix and do any needed
2864 range check. */
2869 {
2870 /* Get the bounds of the slice. */
2871 tree gnu_index_type
2877 /* Check to see that the minimum slice value is in range */
2878 gnu_expr_l
2879 = emit_index_check
2884 /* Check to see that the maximum slice value is in range */
2885 gnu_expr_h
2886 = emit_index_check
2891 /* Derive a good type to convert everything too */
2894 /* Build a compound expression that does the range checks */
2895 gnu_expr
2900 /* Build a conditional expression that returns the range checks
2901 expression if the slice range is not null (max >= min) or
2902 returns the min if the slice range is null */
2903 gnu_expr
2907 gnu_max_expr),
2909 gnu_min_expr)),
2911 }
2912 else
2917 }
2921 {
2925 tree gnu_field;
2929 {
2934 }
2938 /* For discriminant references in tagged types always substitute the
2939 corresponding discriminant as the actual selected component. */
2945 /* For discriminant references of untagged types always substitute the
2946 corresponding stored discriminant. */
2951 /* Handle extracting the real or imaginary part of a complex.
2952 The real part is the first field and the imaginary the last. */
2958 else
2959 {
2962 /* If there are discriminants, the prefix might be
2963 evaluated more than once, which is a problem if it has
2964 side-effects. */
2971 gnu_result
2975 }
2979 }
2983 {
2984 /* The attribute designator (like an enumeration value). */
2987 /* The Elab_Spec and Elab_Body attributes are special in that
2988 Prefix is a unit, not an object with a GCC equivalent. Similarly
2989 for Elaborated, since that variable isn't otherwise known. */
2993 attribute == Attr_Elab_Body
2996 gnat_node));
2999 }
3003 /* Like 'Access as far as we are concerned. */
3011 {
3012 tree gnu_aggr_type;
3014 /* ??? It is wrong to evaluate the type now, but there doesn't
3015 seem to be any other practical way of doing it. */
3019 gnu_aggr_type = gnu_result_type
3024 gnu_aggr_type
3032 {
3033 /* The first element is the discrimant, which we ignore. The
3034 next is the field we're building. Convert the expression
3035 to the type of the field and then to the union type. */
3036 Node_Id gnat_assoc
3039 tree gnu_field_type
3044 }
3047 gnu_result
3049 gnu_aggr_type);
3052 gnu_aggr_type,
3055 gnu_result
3056 = build_binary_op
3061 (Next
3063 else
3067 }
3077 /* Get the operand expression. */
3081 gnu_result
3093 /* If the result is a pointer type, see if we are improperly
3094 converting to a stricter alignment. */
3098 {
3104 post_error_ne_tree_2
3108 }
3116 {
3119 tree gnu_low;
3120 tree gnu_high;
3122 /* GNAT_RANGE is either an N_Range node or an identifier
3123 denoting a subtype. */
3125 {
3128 }
3131 {
3136 }
3137 else
3142 /* If LOW and HIGH are identical, perform an equality test.
3143 Otherwise, ensure that GNU_OBJECT is only evaluated once
3144 and perform a full range test. */
3148 else
3149 {
3151 gnu_result
3157 }
3161 }
3169 ? RDIV_EXPR
3176 /* These can either be operations on booleans or on modular types.
3177 Fall through for boolean types since that's the way GNU_CODES is
3178 set up. */
3180 Modular_Integer_Kind))
3181 {
3182 enum tree_code code
3193 }
3195 /* ... fall through ... */
3207 {
3209 tree gnu_type;
3215 /* If this is a comparison operator, convert any references to
3216 an unconstrained array value into a reference to the
3217 actual array. */
3219 {
3222 }
3224 /* If the result type is a private type, its full view may be a
3225 numeric subtype. The representation we need is that of its base
3226 type, given that it is the result of an arithmetic operation. */
3228 gnu_type = gnu_result_type
3231 /* If this is a shift whose count is not guaranteed to be correct,
3232 we need to adjust the shift count. */
3235 {
3237 tree gnu_max_shift
3245 gnu_rhs
3246 = build_binary_op
3249 gnu_count_type,
3250 gnu_max_shift,
3252 integer_one_node)),
3253 gnu_rhs);
3254 }
3256 /* For right shifts, the type says what kind of shift to do,
3257 so we may need to choose a different type. */
3266 {
3269 }
3273 /* If this is a logical shift with the shift count not verified,
3274 we must return zero if it is too large. We cannot compensate
3275 above in this case. */
3279 gnu_result
3280 = build_cond_expr
3283 gnu_rhs,
3287 gnu_result);
3288 }
3292 {
3295 tree gnu_false
3302 }
3311 /* This case can apply to a boolean or a modular type.
3312 Fall through for a boolean operand since GNU_CODES is set
3313 up to handle this. */
3315 {
3319 gnu_expr);
3321 }
3323 /* ... fall through ... */
3330 else
3339 {
3341 tree gnu_type;
3345 /* The Expression operand can either be an N_Identifier or
3346 Expanded_Name, which must represent a type, or a
3347 N_Qualified_Expression, which contains both the object type and an
3348 initial value for the object. */
3353 {
3354 Entity_Id gnat_desig_type
3365 {
3368 }
3369 else
3370 {
3376 }
3377 }
3378 else
3385 }
3388 /***************************/
3389 /* Chapter 5: Statements: */
3390 /***************************/
3402 /* Get the LHS and RHS of the statement and convert any reference to an
3403 unconstrained array into a reference to the underlying array.
3404 If we are not to do range checking and the RHS is an N_Function_Call,
3405 pass the LHS to the call function. */
3408 /* If the type has a size that overflows, convert this into raise of
3409 Storage_Error: execution shouldn't have gotten here anyway. */
3417 else
3418 {
3419 gnu_rhs
3422 /* If range check is needed, emit code to generate it */
3426 gnu_result
3428 }
3432 {
3435 /* Make the outer COND_EXPR. Avoid non-determinism. */
3444 /* Now make a COND_EXPR for each of the "else if" parts. Put each
3445 into the previous "else" part and point to where to put any
3446 outer "else". Also avoid non-determinism. */
3450 {
3460 }
3463 }
3487 gnu_result
3497 {
3498 /* The gnu function type of the subprogram currently processed. */
3500 /* The return value from the subprogram. */
3502 /* The place to put the return value. */
3503 tree gnu_lhs;
3505 /* If we are dealing with a "return;" from an Ada procedure with
3506 parameters passed by copy in copy out, we need to return a record
3507 containing the final values of these parameters. If the list
3508 contains only one entry, return just that entry.
3510 For a full description of the copy in copy out parameter mechanism,
3511 see the part of the gnat_to_gnu_entity routine dealing with the
3512 translation of subprograms.
3514 But if we have a return label defined, convert this into
3515 a branch to that label. */
3518 {
3522 }
3525 {
3529 else
3530 gnu_ret_val
3533 }
3535 /* If the Ada subprogram is a function, we just need to return the
3536 expression. If the subprogram returns an unconstrained
3537 array, we have to allocate a new version of the result and
3538 return it. If we return by reference, return a pointer. */
3541 {
3542 /* If the current function returns by target pointer and we
3543 are doing a call, pass that target to the call. */
3546 {
3547 gnu_lhs
3552 }
3553 else
3554 {
3558 /* The original return type was unconstrained so dereference
3559 the TARGET pointer in the return value's type. */
3560 gnu_lhs
3563 else
3566 /* Do not remove the padding from GNU_RET_VAL if the inner
3567 type is self-referential since we want to allocate the fixed
3568 size in that case. */
3572 && (TYPE_IS_PADDING_P
3574 && (CONTAINS_PLACEHOLDER_P
3580 gnu_ret_val
3584 {
3587 /* We have two cases: either the function returns with
3588 depressed stack or not. If not, we allocate on the
3589 secondary stack. If so, we allocate in the stack frame.
3590 if no copy is needed, the front end will set By_Ref,
3591 which we handle in the case above. */
3593 gnu_ret_val
3595 gnu_ret_val,
3598 else
3599 gnu_ret_val
3601 gnu_ret_val,
3605 gnat_node);
3606 }
3607 }
3608 }
3609 else
3610 /* If the Ada subprogram is a regular procedure, just return. */
3614 {
3620 }
3623 }
3631 /****************************/
3632 /* Chapter 6: Subprograms: */
3633 /****************************/
3636 /* Unless there is a freeze node, declare the subprogram. We consider
3637 this a "definition" even though we're not generating code for
3638 the subprogram because we will be making the corresponding GCC
3639 node here. */
3648 /* This subprogram doesn't exist for code generation purposes, but we
3649 have to elaborate the types of any parameters, unless they are
3650 imported types (nothing to generate in this case). */
3663 /* For a child unit identifier go up a level to get the
3664 specificaton. We get this when we try to find the spec of
3665 a child unit package that is the compilation unit being compiled. */
3679 /*************************/
3680 /* Chapter 7: Packages: */
3681 /*************************/
3697 /* If this is the body of a generic package - do nothing */
3699 {
3702 }
3713 /*********************************/
3714 /* Chapter 8: Visibility Rules: */
3715 /*********************************/
3719 /* Nothing to do here - but these may appear in list of declarations */
3723 /***********************/
3724 /* Chapter 9: Tasks: */
3725 /***********************/
3736 /***********************************************************/
3737 /* Chapter 10: Program Structure and Compilation Issues: */
3738 /***********************************************************/
3742 /* This is not called for the main unit, which is handled in function
3743 gigi above. */
3755 /* Simply process whatever unit is being inserted. */
3763 /***************************/
3764 /* Chapter 11: Exceptions: */
3765 /***************************/
3768 /* If there is an At_End procedure attached to this node, and the EH
3769 mechanism is SJLJ, we must have at least a corresponding At_End
3770 handler, unless the No_Exception_Handlers restriction is set. */
3785 else
3790 /*******************************/
3791 /* Chapter 12: Generic Units: */
3792 /*******************************/
3802 /* These nodes can appear on a declaration list but there is nothing to
3803 to be done with them. */
3807 /***************************************************/
3808 /* Chapter 13: Representation Clauses and */
3809 /* Implementation-Dependent Features: */
3810 /***************************************************/
3816 /* The only one we need deal with is for 'Address. For the others, SEM
3817 puts the information elsewhere. We need only deal with 'Address
3818 if the object has a Freeze_Node (which it never will currently). */
3823 /* Get the value to use as the address and save it as the
3824 equivalent for GNAT_TEMP. When the object is frozen,
3825 gnat_to_gnu_entity will do the right thing. */
3833 /* We do nothing with these. SEM puts the information elsewhere. */
3839 {
3845 /* First process inputs, then outputs, then clobbers. */
3848 {
3853 gnu_input_list
3856 }
3860 {
3865 gnu_output_list
3868 }
3872 gnu_clobber_list
3875 gnu_clobber_list);
3883 }
3884 else
3889 /***************************************************/
3890 /* Added Nodes */
3891 /***************************************************/
3909 {
3911 tree gnu_obj_type;
3912 tree gnu_obj_size;
3915 /* If this is a thin pointer, we must dereference it to create
3916 a fat pointer, then go back below to a thin pointer. The
3917 reason for this is that we need a fat pointer someplace in
3918 order to properly compute the size. */
3922 gnu_ptr));
3924 /* If this is an unconstrained array, we know the object must
3925 have been allocated with the template in front of the object.
3926 So pass the template address, but get the total size. Do this
3927 by converting to a thin pointer. */
3929 gnu_ptr
3931 (TYPE_OBJECT_RECORD_TYPE
3933 gnu_ptr);
3941 {
3944 tree gnu_byte_offset
3951 }
3956 gnat_node);
3957 }
3964 {
3967 }
3972 /* If the type is VOID, this is a statement, so we need to
3973 generate the code for the call. Handle a Condition, if there
3974 is one. */
3976 {
3983 }
3984 else
3989 /* If the result is a pointer type, see if we are either converting
3990 from a non-pointer or from a pointer to a type with a different
3991 alias set and warn if so. If the result defined in the same unit as
3992 this unchecked convertion, we can allow this because we can know to
3993 make that type have alias set 0. */
3994 {
4005 {
4006 post_error_ne
4009 post_error
4011 gnat_node);
4012 post_error_ne
4015 }
4016 }
4029 }
4031 /* If we pushed our level as part of processing the elaboration routine,
4032 pop it back now. */
4034 {
4039 }
4041 /* Set the location information into the result. Note that we may have
4042 no result if we just expanded a procedure with no side-effects. */
4046 /* If we're supposed to return something of void_type, it means we have
4047 something we're elaborating for effect, so just return. */
4051 /* If the result is a constant that overflows, raise constraint error. */
4054 {
4057 gnu_result
4060 }
4062 /* If our result has side-effects and is of an unconstrained type,
4063 make a SAVE_EXPR so that we can be sure it will only be referenced
4064 once. Note we must do this before any conversions. */
4070 /* Now convert the result to the proper type. If the type is void or if
4071 we have no result, return error_mark_node to show we have no result.
4072 If the type of the result is correct or if we have a label (which doesn't
4073 have any well-defined type), return our result. Also don't do the
4074 conversion if the "desired" type involves a PLACEHOLDER_EXPR in its size
4075 since those are the cases where the front end may have the type wrong due
4076 to "instantiating" the unconstrained record with discriminant values
4077 or if this is a FIELD_DECL. If this is the Name of an assignment
4078 statement or a parameter of a procedure call, return what we have since
4079 the RHS has to be converted to our type there in that case, unless
4080 GNU_RESULT_TYPE has a simpler size. Similarly, if the two types are
4081 record types with the same name, the expression type has integral mode,
4082 and GNU_RESULT_TYPE BLKmode, don't convert. This will be the case when
4083 we are converting from a packable type to its actual type and we need
4084 those conversions to be NOPs in order for assignments into these types to
4085 work properly if the inner object is a bitfield and hence can't have
4086 its address taken. Finally, don't convert integral types that are the
4087 operand of an unchecked conversion since we need to ignore those
4088 conversions (for 'Valid). Otherwise, convert the result to the proper
4089 type. */
4109 && (CONTAINS_PLACEHOLDER_P
4113 {
4114 /* In this case remove padding only if the inner object is of
4115 self-referential size: in that case it must be an object of
4116 unconstrained type with a default discriminant. In other cases,
4117 we want to avoid copying too much data. */
4124 gnu_result);
4125 }
4141 {
4142 /* Remove any padding record, but do nothing more in this case. */
4146 gnu_result);
4147 }
4155 /* We don't need any NOP_EXPR or NON_LVALUE_EXPR on GNU_RESULT. */
4162 }
4163 \f
4164 /* Record the current code position in GNAT_NODE. */
4166 static void
4168 {
4173 }
4175 /* Insert the code for GNAT_NODE at the position saved for that node. */
4177 static void
4179 {
4182 }
4183 \f
4184 /* Start a new statement group chained to the previous group. */
4186 static void
4188 {
4191 /* First see if we can get one from the free list. */
4194 else
4200 }
4202 /* Add GNU_STMT to the current statement group. */
4204 void
4206 {
4209 /* If we're at top level, show everything in here is in use in case
4210 any of it is shared by a subprogram. */
4214 }
4216 /* Similar, but set the location of GNU_STMT to that of GNAT_NODE. */
4218 void
4220 {
4224 }
4226 /* Add a declaration statement for GNU_DECL to the current statement group.
4227 Get SLOC from Entity_Id. */
4229 void
4231 {
4232 tree gnu_stmt;
4234 /* If this is a variable that Gigi is to ignore, we may have been given
4235 an ERROR_MARK. So test for it. We also might have been given a
4236 reference for a renaming. So only do something for a decl. Also
4237 ignore a TYPE_DECL for an UNCONSTRAINED_ARRAY_TYPE. */
4243 /* If we are global, we don't want to actually output the DECL_EXPR for
4244 this decl since we already have evaluated the expressions in the
4245 sizes and positions as globals and doing it again would be wrong.
4246 But we do have to mark everything as used. */
4250 else
4251 {
4255 {
4259 }
4260 }
4262 /* If this is a DECL_EXPR for a variable with DECL_INITIAl set,
4263 there are two cases we need to handle here. */
4265 {
4269 /* If this is a DECL_EXPR for a variable with DECL_INITIAL set
4270 and decl has a padded type, convert it to the unpadded type so the
4271 assignment is done properly. */
4274 gnu_lhs
4277 /* Otherwise, if this is going into memory and the initializer isn't
4278 valid for the assembler and loader. Gimplification could do this,
4279 but would be run too late if -fno-unit-at-a-time. */
4286 {
4287 tree gnu_assign_stmt
4296 }
4297 }
4298 }
4300 /* Utility function to mark nodes with TREE_VISITED and types as having their
4301 sized gimplified. Called from walk_tree. We use this to indicate all
4302 variable sizes and positions in global types may not be shared by any
4303 subprogram. */
4305 static tree
4307 {
4311 /* Don't mark a dummy type as visited because we want to mark its sizes
4312 and fields once it's filled in. */
4320 }
4322 /* Likewise, but to mark as unvisited. */
4324 static tree
4327 {
4331 }
4333 /* Add GNU_CLEANUP, a cleanup action, to the current code group. */
4335 static void
4337 {
4339 }
4341 /* Set the BLOCK node corresponding to the current code group to GNU_BLOCK. */
4343 void
4345 {
4348 }
4350 /* Return code corresponding to the current code group. It is normally
4351 a STATEMENT_LIST, but may also be a BIND_EXPR or TRY_FINALLY_EXPR if
4352 BLOCK or cleanups were set. */
4354 static tree
4356 {
4360 /* If this is a null list, allocate a new STATEMENT_LIST. Then, if there
4361 are cleanups, make a TRY_FINALLY_EXPR. Last, if there is a BLOCK,
4362 make a BIND_EXPR. Note that we nest in that because the cleanup may
4363 reference variables in the block. */
4375 /* Remove this group from the stack and add it to the free list. */
4381 }
4383 /* Add a list of statements from GNAT_LIST, a possibly-empty list of
4384 statements.*/
4386 static void
4388 {
4389 Node_Id gnat_node;
4395 }
4397 /* Build a tree from GNAT_LIST, a possibly-empty list of statements.
4398 If BINDING_P is true, push and pop a binding level around the list. */
4400 static tree
4402 {
4412 }
4413 \f
4414 /* Push and pop routines for stacks. We keep a free list around so we
4415 don't waste tree nodes. */
4417 static void
4419 {
4423 {
4428 }
4429 else
4433 }
4435 static void
4437 {
4443 }
4444 \f
4445 /* GNU_STMT is a statement. We generate code for that statement. */
4447 void
4449 {
4450 #if 0
4452 #endif
4455 {
4456 #if 0
4458 /* First write a volatile ASM_INPUT to prevent anything from being
4459 moved. */
4465 modifier);
4468 #endif
4472 }
4473 }
4474 \f
4475 /* Generate GIMPLE in place for the expression at *EXPR_P. */
4477 int
4479 {
4486 {
4488 /* If this is for a scalar, just make a VAR_DECL for it. If for
4489 an aggregate, get a null pointer of the appropriate type and
4490 dereference it. */
4494 integer_zero_node));
4495 else
4496 {
4499 }
4505 /* We should only do this if we are just elaborating for side-effects,
4506 but we can't know that yet. */
4511 /* If we're taking the address of a constant CONSTRUCTOR, force it to
4512 be put into static memory. We know it's going to be readonly given
4513 the semantics we have and it's required to be static memory in
4514 the case when the reference is in an elaboration procedure. */
4517 {
4518 tree new_var
4528 }
4532 /* We have a kludge here. If the FIELD_DECL is from a fat pointer and is
4533 from an early dummy type, replace it with the proper FIELD_DECL. */
4536 {
4540 }
4542 /* ... fall through ... */
4546 }
4547 }
4549 /* Generate GIMPLE in place for the statement at *STMT_P. */
4551 static enum gimplify_status
4553 {
4557 {
4567 {
4571 /* Set to emit the statements of the loop. */
4574 /* We first emit the start label and then a conditional jump to
4575 the end label if there's a top condition, then the body of the
4576 loop, then a conditional branch to the end label, then the update,
4577 if any, and finally a jump to the start label and the definition
4578 of the end label. */
4580 gnu_start_label),
4581 stmt_p);
4588 void_type_node,
4589 gnu_end_label)),
4590 stmt_p);
4599 void_type_node,
4600 gnu_end_label)),
4601 stmt_p);
4607 gnu_start_label),
4608 stmt_p);
4610 gnu_end_label),
4611 stmt_p);
4613 }
4616 /* Build a statement to jump to the corresponding end label, then
4617 see if it needs to be conditional. */
4626 }
4627 }
4628 \f
4629 /* Force references to each of the entities in packages GNAT_NODE with's
4630 so that the debugging information for all of them are identical
4631 in all clients. Operate recursively on anything it with's, but check
4632 that we aren't elaborating something more than once. */
4634 /* The reason for this routine's existence is two-fold.
4635 First, with some debugging formats, notably MDEBUG on SGI
4636 IRIX, the linker will remove duplicate debugging information if two
4637 clients have identical debugguing information. With the normal scheme
4638 of elaboration, this does not usually occur, since entities in with'ed
4639 packages are elaborated on demand, and if clients have different usage
4640 patterns, the normal case, then the order and selection of entities
4641 will differ. In most cases however, it seems that linkers do not know
4642 how to eliminate duplicate debugging information, even if it is
4643 identical, so the use of this routine would increase the total amount
4644 of debugging information in the final executable.
4646 Second, this routine is called in type_annotate mode, to compute DDA
4647 information for types in withed units, for ASIS use */
4649 static void
4651 {
4654 /* Process each unit only once. As we trace the context of all relevant
4655 units transitively, including generic bodies, we may encounter the
4656 same generic unit repeatedly */
4661 /* Save entities in all context units. A body may have an implicit_with
4662 on its own spec, if the context includes a child unit, so don't save
4663 the spec twice. */
4671 {
4675 {
4692 }
4694 {
4695 Node_Id gnat_body
4698 /* Retrieve compilation unit node of generic body. */
4703 /* If body is available, elaborate its context. */
4706 }
4707 }
4711 }
4712 \f
4713 /* Do the processing of N_Freeze_Entity, GNAT_NODE. */
4715 static void
4717 {
4719 tree gnu_old;
4720 tree gnu_new;
4721 tree gnu_init
4726 /* If this is a package, need to generate code for the package. */
4728 {
4729 insert_code_for
4733 }
4735 /* Check for old definition after the above call. This Freeze_Node
4736 might be for one its Itypes. */
4737 gnu_old
4740 /* If this entity has an Address representation clause, GNU_OLD is the
4741 address, so discard it here. */
4745 /* Don't do anything for class-wide types they are always
4746 transformed into their root type. */
4752 /* Don't do anything for subprograms that may have been elaborated before
4753 their freeze nodes. This can happen, for example because of an inner call
4754 in an instance body. */
4761 /* If we have a non-dummy type old tree, we have nothing to do. Unless
4762 this is the public view of a private type whose full view was not
4763 delayed, this node was never delayed as it should have been.
4764 Also allow this to happen for concurrent types since we may have
4765 frozen both the Corresponding_Record_Type and this type. */
4769 {
4775 }
4777 /* Reset the saved tree, if any, and elaborate the object or type for real.
4778 If there is a full declaration, elaborate it and copy the type to
4779 GNAT_ENTITY. Likewise if this is the record subtype corresponding to
4780 a class wide type or subtype. */
4782 {
4791 }
4795 {
4798 /* The above call may have defined this entity (the simplest example
4799 of this is when we have a private enumeral type since the bounds
4800 will have the public view. */
4806 }
4807 else
4810 /* If we've made any pointers to the old version of this type, we
4811 have to update them. */
4815 }
4816 \f
4817 /* Process the list of inlined subprograms of GNAT_NODE, which is an
4818 N_Compilation_Unit. */
4820 static void
4822 {
4823 Entity_Id gnat_entity;
4824 Node_Id gnat_body;
4826 /* If we can inline, generate RTL for all the inlined subprograms.
4827 Define the entity first so we set DECL_EXTERNAL. */
4832 {
4836 {
4837 /* ??? This really should always be Present. */
4841 gnat_body
4843 }
4846 {
4849 }
4850 }
4851 }
4852 \f
4853 /* Elaborate decls in the lists GNAT_DECLS and GNAT_DECLS2, if present.
4854 We make two passes, one to elaborate anything other than bodies (but
4855 we declare a function if there was no spec). The second pass
4856 elaborates the bodies.
4858 GNAT_END_LIST gives the element in the list past the end. Normally,
4859 this is Empty, but can be First_Real_Statement for a
4860 Handled_Sequence_Of_Statements.
4862 We make a complete pass through both lists if PASS1P is true, then make
4863 the second pass over both lists if PASS2P is true. The lists usually
4864 correspond to the public and private parts of a package. */
4866 static void
4869 {
4871 Node_Id gnat_decl;
4881 {
4882 /* For package specs, we recurse inside the declarations,
4883 thus taking the two pass approach inside the boundary. */
4891 /* Similarly for any declarations in the actions of a
4892 freeze node. */
4894 {
4897 }
4899 /* Package bodies with freeze nodes get their elaboration deferred
4900 until the freeze node, but the code must be placed in the right
4901 place, so record the code position now. */
4909 (Corresponding_Spec
4912 record_code_position
4915 /* We defer most subprogram bodies to the second pass. */
4917 {
4919 {
4925 }
4926 }
4927 /* For bodies and stubs that act as their own specs, the entity
4928 itself must be elaborated in the first pass, because it may
4929 be used in other declarations. */
4931 {
4932 Node_Id gnat_subprog_id =
4939 }
4941 /* Concurrent stubs stand for the corresponding subprogram bodies,
4942 which are deferred like other bodies. */
4945 ;
4946 else
4948 }
4950 /* Here we elaborate everything we deferred above except for package bodies,
4951 which are elaborated at their freeze nodes. Note that we must also
4952 go inside things (package specs and freeze nodes) the first pass did. */
4958 {
4974 }
4975 }
4976 \f
4977 /* Emit code for a range check. GNU_EXPR is the expression to be checked,
4978 GNAT_RANGE_TYPE the gnat type or subtype containing the bounds against
4979 which we have to check. */
4981 static tree
4983 {
4989 /* If GNU_EXPR has an integral type that is narrower than GNU_RANGE_TYPE,
4990 we can't do anything since we might be truncating the bounds. No
4991 check is needed in this case. */
4997 /* Checked expressions must be evaluated only once. */
5000 /* There's no good type to use here, so we might as well use
5001 integer_type_node. Note that the form of the check is
5002 (not (expr >= lo)) or (not (expr >= hi))
5003 the reason for this slightly convoluted form is that NaN's
5004 are not considered to be in range in the float case. */
5005 return emit_check
5007 invert_truthvalue
5011 invert_truthvalue
5015 gnu_high)))),
5017 }
5018 \f
5019 /* Emit code for an index check. GNU_ARRAY_OBJECT is the array object
5020 which we are about to index, GNU_EXPR is the index expression to be
5021 checked, GNU_LOW and GNU_HIGH are the lower and upper bounds
5022 against which GNU_EXPR has to be checked. Note that for index
5023 checking we cannot use the emit_range_check function (although very
5024 similar code needs to be generated in both cases) since for index
5025 checking the array type against which we are checking the indeces
5026 may be unconstrained and consequently we need to retrieve the
5027 actual index bounds from the array object itself
5028 (GNU_ARRAY_OBJECT). The place where we need to do that is in
5029 subprograms having unconstrained array formal parameters */
5031 static tree
5033 tree gnu_expr,
5034 tree gnu_low,
5035 tree gnu_high)
5036 {
5037 tree gnu_expr_check;
5039 /* Checked expressions must be evaluated only once. */
5042 /* Must do this computation in the base type in case the expression's
5043 type is an unsigned subtypes. */
5046 /* If GNU_LOW or GNU_HIGH are a PLACEHOLDER_EXPR, qualify them by
5047 the object we are handling. */
5051 /* There's no good type to use here, so we might as well use
5052 integer_type_node. */
5053 return emit_check
5056 gnu_expr_check,
5058 gnu_low)),
5060 gnu_expr_check,
5062 gnu_high))),
5064 }
5065 \f
5066 /* GNU_COND contains the condition corresponding to an access, discriminant or
5067 range check of value GNU_EXPR. Build a COND_EXPR that returns GNU_EXPR if
5068 GNU_COND is false and raises a CONSTRAINT_ERROR if GNU_COND is true.
5069 REASON is the code that says why the exception was raised. */
5071 static tree
5073 {
5074 tree gnu_call;
5075 tree gnu_result;
5079 /* Use an outer COMPOUND_EXPR to make sure that GNU_EXPR will get evaluated
5080 in front of the comparison in case it ends up being a SAVE_EXPR. Put the
5081 whole thing inside its own SAVE_EXPR so the inner SAVE_EXPR doesn't leak
5082 out. */
5086 gnu_expr));
5088 /* If GNU_EXPR has side effects, make the outer COMPOUND_EXPR and
5089 protect it. Otherwise, show GNU_RESULT has no side effects: we
5090 don't need to evaluate it just for the check. */
5092 gnu_result
5094 else
5097 /* ??? Unfortunately, if we don't put a SAVE_EXPR around this whole thing,
5098 we will repeatedly do the test. It would be nice if GCC was able
5099 to optimize this and only do it once. */
5101 }
5102 \f
5103 /* Return an expression that converts GNU_EXPR to GNAT_TYPE, doing
5104 overflow checks if OVERFLOW_P is nonzero and range checks if
5105 RANGE_P is nonzero. GNAT_TYPE is known to be an integral type.
5106 If TRUNCATE_P is nonzero, do a float to integer conversion with
5107 truncation; otherwise round. */
5109 static tree
5112 {
5120 /* If we are not doing any checks, the output is an integral type, and
5121 the input is not a floating type, just do the conversion. This
5122 shortcut is required to avoid problems with packed array types
5123 and simplifies code in all cases anyway. */
5128 /* First convert the expression to its base type. This
5129 will never generate code, but makes the tests below much simpler.
5130 But don't do this if converting from an integer type to an unconstrained
5131 array type since then we need to get the bounds from the original
5132 (unpacked) type. */
5136 /* If overflow checks are requested, we need to be sure the result will
5137 fit in the output base type. But don't do this if the input
5138 is integer and the output floating-point. */
5141 {
5142 /* Ensure GNU_EXPR only gets evaluated once. */
5150 /* Convert the lower bounds to signed types, so we're sure we're
5151 comparing them properly. Likewise, convert the upper bounds
5152 to unsigned types. */
5166 /* Check each bound separately and only if the result bound
5167 is tighter than the bound on the input type. Note that all the
5168 types are base types, so the bounds must be constant. Also,
5169 the comparison is done in the base type of the input, which
5170 always has the proper signedness. First check for input
5171 integer (which means output integer), output float (which means
5172 both float), or mixed, in which case we always compare.
5173 Note that we have to do the comparison which would *fail* in the
5174 case of an error since if it's an FP comparison and one of the
5175 values is a NaN or Inf, the comparison will fail. */
5182 gnu_cond
5183 = invert_truthvalue
5186 gnu_out_lb)));
5194 gnu_cond
5196 invert_truthvalue
5198 gnu_input,
5200 gnu_out_ub))));
5204 CE_Overflow_Check_Failed);
5205 }
5207 /* Now convert to the result base type. If this is a non-truncating
5208 float-to-integer conversion, round. */
5211 {
5217 /* The following calculations depend on proper rounding to even
5218 of each arithmetic operation. In order to prevent excess
5219 precision from spoiling this property, use the widest hardware
5220 floating-point type.
5222 FIXME: For maximum efficiency, this should only be done for machines
5223 and types where intermediates may have extra precision. */
5226 /* FIXME: Should not have padding in the first place */
5231 /* Compute the exact value calc_type'Pred (0.5) at compile time. */
5235 half_minus_pred_half);
5238 /* If the input is strictly negative, subtract this value
5239 and otherwise add it from the input. For 0.5, the result
5240 is exactly between 1.0 and the machine number preceding 1.0
5241 (for calc_type). Since the last bit of 1.0 is even, this 0.5
5242 will round to 1.0, while all other number with an absolute
5243 value less than 0.5 round to 0.0. For larger numbers exactly
5244 halfway between integers, rounding will always be correct as
5245 the true mathematical result will be closer to the higher
5246 integer compared to the lower one. So, this constant works
5247 for all floating-point numbers.
5249 The reason to use the same constant with subtract/add instead
5250 of a positive and negative constant is to allow the comparison
5251 to be scheduled in parallel with retrieval of the constant and
5252 conversion of the input to the calc_type (if necessary).
5253 */
5260 gnu_add_pred_half
5262 gnu_subtract_pred_half
5266 }
5272 else
5275 /* Finally, do the range check if requested. Note that if the
5276 result type is a modular type, the range check is actually
5277 an overflow check. */
5285 }
5286 \f
5287 /* Return 1 if GNU_EXPR can be directly addressed. This is the case unless
5288 it is an expression involving computation or if it involves a bitfield
5289 reference. This returns the same as gnat_mark_addressable in most
5290 cases. */
5292 static bool
5294 {
5296 {
5301 /* All DECLs are addressable: if they are in a register, we can force
5302 them to memory. */
5328 {
5329 /* This is addressable if we can avoid a copy. */
5343 }
5347 }
5348 }
5349 \f
5350 /* Do the processing for the declaration of a GNAT_ENTITY, a type. If
5351 a separate Freeze node exists, delay the bulk of the processing. Otherwise
5352 make a GCC type for GNAT_ENTITY and set up the correspondance. */
5354 void
5356 {
5357 tree gnu_old
5359 tree gnu_new;
5361 /* If we are to delay elaboration of this type, just do any
5362 elaborations needed for expressions within the declaration and
5363 make a dummy type entry for this node and its Full_View (if
5364 any) in case something points to it. Don't do this if it
5365 has already been done (the only way that can happen is if
5366 the private completion is also delayed). */
5372 {
5376 {
5385 }
5388 }
5390 /* If we saved away a dummy type for this node it means that this
5391 made the type that corresponds to the full type of an incomplete
5392 type. Clear that type for now and then update the type in the
5393 pointers. */
5395 {
5398 {
5399 /* If this was a withed access type, this is not an error
5400 and merely indicates we've already elaborated the type
5401 already. */
5404 }
5407 }
5409 /* Now fully elaborate the type. */
5413 /* If we have an old type and we've made pointers to this type,
5414 update those pointers. */
5419 /* If this is a record type corresponding to a task or protected type
5420 that is a completion of an incomplete type, perform a similar update
5421 on the type. */
5422 /* ??? Including protected types here is a guess. */
5427 {
5428 tree gnu_task_old
5438 }
5439 }
5440 \f
5441 /* GNAT_ASSOC is the front of the Component_Associations of an N_Aggregate.
5442 GNU_TYPE is the GCC type of the corresponding record.
5444 Return a CONSTRUCTOR to build the record. */
5446 static tree
5448 {
5451 /* We test for GNU_FIELD being empty in the case where a variant
5452 was the last thing since we don't take things off GNAT_ASSOC in
5453 that case. We check GNAT_ASSOC in case we have a variant, but it
5454 has no fields. */
5458 {
5463 /* The expander is supposed to put a single component selector name
5464 in every record component association */
5467 /* Ignore fields that have Corresponding_Discriminants since we'll
5468 be setting that field in the parent. */
5473 /* Before assigning a value in an aggregate make sure range checks
5474 are done if required. Then convert to the type of the field. */
5480 /* Add the field and expression to the list. */
5482 }
5486 #ifdef ENABLE_CHECKING
5487 {
5488 tree gnu_field;
5490 /* Verify every enty in GNU_LIST was used. */
5493 }
5494 #endif
5497 }
5499 /* Builds a possibly nested constructor for array aggregates. GNAT_EXPR
5500 is the first element of an array aggregate. It may itself be an
5501 aggregate (an array or record aggregate). GNU_ARRAY_TYPE is the gnu type
5502 corresponding to the array aggregate. GNAT_COMPONENT_TYPE is the type
5503 of the array component. It is needed for range checking. */
5505 static tree
5507 Entity_Id gnat_component_type)
5508 {
5511 tree gnu_expr;
5514 {
5515 /* If the expression is itself an array aggregate then first build the
5516 innermost constructor if it is part of our array (multi-dimensional
5517 case). */
5524 gnat_component_type);
5525 else
5526 {
5529 /* before assigning the element to the array make sure it is
5530 in range */
5533 }
5535 gnu_expr_list
5537 gnu_expr_list);
5540 }
5543 }
5544 \f
5545 /* Subroutine of assoc_to_constructor: VALUES is a list of field associations,
5546 some of which are from RECORD_TYPE. Return a CONSTRUCTOR consisting
5547 of the associations that are from RECORD_TYPE. If we see an internal
5548 record, make a recursive call to fill it in as well. */
5550 static tree
5552 {
5557 {
5560 /* _Parent is an internal field, but may have values in the aggregate,
5561 so check for values first. */
5563 {
5566 }
5569 {
5573 }
5574 else
5575 /* If we have a record subtype, the names will match, but not the
5576 actual FIELD_DECLs. */
5579 {
5582 }
5588 }
5591 }
5592 \f
5593 /* EXP is to be treated as an array or record. Handle the cases when it is
5594 an access object and perform the required dereferences. */
5596 static tree
5598 {
5599 /* If the type is a pointer, dereference it. */
5604 /* If we got a padded type, remove it too. */
5610 }
5611 \f
5612 /* Protect EXP from multiple evaluation. This may make a SAVE_EXPR. */
5614 tree
5616 {
5619 /* If this has no side effects, we don't need to do anything. */
5623 /* If it is a conversion, protect what's inside the conversion.
5624 Similarly, if we're indirectly referencing something, we only
5625 actually need to protect the address since the data itself can't
5626 change in these situations. */
5635 /* If EXP is a fat pointer or something that can be placed into a register,
5636 just make a SAVE_EXPR. */
5640 /* Otherwise, dereference, protect the address, and re-reference. */
5641 else
5642 return
5646 exp)));
5647 }
5648 \f
5649 /* This is equivalent to stabilize_reference in GCC's tree.c, but we know
5650 how to handle our new nodes and we take an extra argument that says
5651 whether to force evaluation of everything. */
5653 tree
5655 {
5658 tree result;
5661 {
5665 /* No action is needed in this case. */
5677 result
5686 force));
5692 force),
5700 force),
5702 force));
5710 force),
5717 force),
5719 force));
5722 /* If arg isn't a kind of lvalue we recognize, make no change.
5723 Caller should recognize the error for an invalid lvalue. */
5729 }
5733 /* TREE_THIS_VOLATILE and TREE_SIDE_EFFECTS attached to the initial
5734 expression may not be sustained across some paths, such as the way via
5735 build1 for INDIRECT_REF. We re-populate those flags here for the general
5736 case, which is consistent with the GCC version of this routine.
5738 Special care should be taken regarding TREE_SIDE_EFFECTS, because some
5739 paths introduce side effects where there was none initially (e.g. calls
5740 to save_expr), and we also want to keep track of that. */
5746 }
5748 /* Similar to stabilize_reference_1 in tree.c, but supports an extra
5749 arg to force a SAVE_EXPR for everything. */
5751 static tree
5753 {
5756 tree result;
5758 /* We cannot ignore const expressions because it might be a reference
5759 to a const array but whose index contains side-effects. But we can
5760 ignore things that are actual constant or that already have been
5761 handled by this function. */
5767 {
5775 /* If this is a COMPONENT_REF of a fat pointer, save the entire
5776 fat pointer. This may be more efficient, but will also allow
5777 us to more easily find the match for the PLACEHOLDER_EXPR. */
5782 force),
5786 else
5791 /* Constants need no processing. In fact, we should never reach
5792 here. */
5796 /* Recursively stabilize each operand. */
5800 force));
5804 /* Recursively stabilize each operand. */
5807 force));
5812 }
5819 }
5820 \f
5823 /* Convert Sloc into *LOCUS (a location_t). Return true if this Sloc
5824 corresponds to a source code location and false if it doesn't. In the
5825 latter case, we don't update *LOCUS. We also set the Gigi global variable
5826 REF_FILENAME to the reference file name as given by sinput (i.e no
5827 directory). */
5829 bool
5831 {
5832 /* If node not from source code, ignore. */
5836 /* Use the identifier table to make a hashed, permanent copy of the filename,
5837 since the name table gets reallocated after Gigi returns but before all
5838 the debugging information is output. The __gnat_to_canonical_file_spec
5839 call translates filenames from pragmas Source_Reference that contain host
5840 style syntax not understood by gdb. */
5841 locus->file
5842 = IDENTIFIER_POINTER
5843 (get_identifier
5844 (__gnat_to_canonical_file_spec
5849 ref_filename
5850 = IDENTIFIER_POINTER
5851 (get_identifier
5855 }
5857 /* Similar to annotate_with_locus, but start with the Sloc of GNAT_NODE and
5858 don't do anything if it doesn't correspond to a source location. */
5860 static void
5862 {
5863 location_t locus;
5869 }
5870 \f
5871 /* Post an error message. MSG is the error message, properly annotated.
5872 NODE is the node at which to post the error and the node to use for the
5873 "&" substitution. */
5875 void
5877 {
5878 String_Template temp;
5879 Fat_Pointer fp;
5885 }
5887 /* Similar, but NODE is the node at which to post the error and ENT
5888 is the node to use for the "&" substitution. */
5890 void
5892 {
5893 String_Template temp;
5894 Fat_Pointer fp;
5900 }
5902 /* Similar, but NODE is the node at which to post the error, ENT is the node
5903 to use for the "&" substitution, and N is the number to use for the ^. */
5905 void
5907 {
5908 String_Template temp;
5909 Fat_Pointer fp;
5917 }
5918 \f
5919 /* Similar to post_error_ne_num, but T is a GCC tree representing the
5920 number to write. If the tree represents a constant that fits within
5921 a host integer, the text inside curly brackets in MSG will be output
5922 (presumably including a '^'). Otherwise that text will not be output
5923 and the text inside square brackets will be output instead. */
5925 void
5927 {
5930 Fat_Pointer fp;
5938 #if HOST_BITS_PER_WIDE_INT > HOST_BITS_PER_INT
5939 &&
5940 compare_tree_int
5942 #endif
5943 )
5944 {
5947 }
5948 else
5952 {
5958 ;
5959 else
5961 }
5968 }
5970 /* Similar to post_error_ne_tree, except that NUM is a second
5971 integer to write in the message. */
5973 void
5975 Node_Id node,
5976 Entity_Id ent,
5977 tree t,
5979 {
5982 }
5984 /* Set the node for a second '&' in the error message. */
5986 void
5988 {
5990 }
5991 \f
5992 /* Initialize the table that maps GNAT codes to GCC codes for simple
5993 binary and unary operations. */
5995 void
5997 {
6023 }