| blob | 4defe553e628f50b28509662d7b27cecddcd7104 |
1 /****************************************************************************
2 * *
3 * GNAT COMPILER COMPONENTS *
4 * *
5 * T R A N S *
6 * *
7 * C Implementation File *
8 * *
9 * Copyright (C) 1992-2004, 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 /* Constants for +0.5 and -0.5 for float-to-integer rounding. */
171 \f
172 /* This is the main program of the back-end. It sets up all the table
173 structures and then generates code. */
175 void
183 Int gigi_operating_mode)
184 {
185 tree gnu_standard_long_long_float;
186 tree gnu_standard_exception_type;
206 /* If we are just annotating types, give VOID_TYPE zero sizes to avoid
207 errors. */
209 {
212 }
214 /* Save the type we made for integer as the type for Standard.Integer.
215 Then make the rest of the standard types. Note that some of these
216 may be subtypes. */
222 gnu_standard_long_long_float
224 gnu_standard_exception_type
229 /* Process any Pragma Ident for the main unit. */
230 #ifdef ASM_OUTPUT_IDENT
232 ASM_OUTPUT_IDENT
235 #endif
237 /* If we are using the GCC exception mechanism, let GCC know. */
246 /* Now see if we have any elaboration procedures to deal with. */
248 {
250 tree gnu_stmts;
252 /* Mark everything we have as not visited. */
255 /* Set the current function to be the elaboration procedure and gimplify
256 what we have. */
260 /* We should have a BIND_EXPR, but it may or may not have any statements
261 in it. If it doesn't have any, we have nothing to do. */
266 /* If there are no statements, there is no elaboration code. */
269 else
270 {
271 /* Otherwise, compile the function. Note that we'll be gimplifying
272 it twice, but that's fine for the nodes we use. */
275 }
276 }
277 }
278 \f
279 /* Perform initializations for this module. */
281 void
283 {
284 /* Initialize ourselves. */
288 /* Enable GNAT stack checking method if needed */
297 }
298 \f
299 /* Subroutine of gnat_to_gnu to translate gnat_node, an N_Identifier,
300 to a GCC tree, which is returned. GNU_RESULT_TYPE_P is a pointer to
301 where we should place the result type. */
303 static tree
305 {
306 tree gnu_result_type;
307 tree gnu_result;
310 /* If the Etype of this node does not equal the Etype of the Entity,
311 something is wrong with the entity map, probably in generic
312 instantiation. However, this does not apply to types. Since we sometime
313 have strange Ekind's, just do this test for objects. Also, if the Etype of
314 the Entity is private, the Etype of the N_Identifier is allowed to be the
315 full type and also we consider a packed array type to be the same as the
316 original type. Similarly, a class-wide type is equivalent to a subtype of
317 itself. Finally, if the types are Itypes, one may be a copy of the other,
318 which is also legal. */
341 /* If this is a reference to a deferred constant whose partial view is an
342 unconstrained private type, the proper type is on the full view of the
343 constant, not on the full view of the type, which may be unconstrained.
345 This may be a reference to a type, for example in the prefix of the
346 attribute Position, generated for dispatching code (see Make_DT in
347 exp_disp,adb). In that case we need the type itself, not is parent,
348 in particular if it is a derived type */
353 {
357 }
358 else
359 {
360 /* Expand the type of this identitier first, in case it is an enumeral
361 literal, which only get made when the type is expanded. There is no
362 order-of-elaboration issue here. We want to use the Actual_Subtype if
363 it has already been elaborated, otherwise the Etype. Avoid using
364 Actual_Subtype for packed arrays to simplify things. */
372 else
376 }
380 /* If we are in an exception handler, force this variable into memory to
381 ensure optimization does not remove stores that appear redundant but are
382 actually needed in case an exception occurs.
384 ??? Note that we need not do this if the variable is declared within the
385 handler, only if it is referenced in the handler and declared in an
386 enclosing block, but we have no way of testing that right now.
388 ??? Also, for now all we can do is make it volatile. But we only
389 do this for SJLJ. */
394 /* Some objects (such as parameters passed by reference, globals of
395 variable size, and renamed objects) actually represent the address
396 of the object. In that case, we must do the dereference. Likewise,
397 deal with parameters to foreign convention subprograms. Call fold
398 here since GNU_RESULT may be a CONST_DECL. */
403 {
405 tree initial;
409 gnu_result
412 gnu_result));
414 /* If the object is constant, we try to do the dereference directly
415 through the DECL_INITIAL. This is actually required in order to get
416 correct aliasing information for renamed objects that are components
417 of non-aliased aggregates, because the type of the renamed object and
418 that of the aggregate don't alias.
420 Note that we expect the initial value to have been stabilized.
421 If it contains e.g. a variable reference, we certainly don't want
422 to re-evaluate the variable each time the renaming is used.
424 Stabilization is currently not performed at the global level but
425 create_var_decl avoids setting DECL_INITIAL if the value is not
426 constant then, and we get to the pointer dereference below.
428 ??? Couldn't the aliasing issue show up again in this case ?
429 There is no obvious reason why not. */
432 /* Strip possible conversion to reference type. */
434 == NOP_EXPR
442 else
447 }
449 /* The GNAT tree has the type of a function as the type of its result. Also
450 use the type of the result if the Etype is a subtype which is nominally
451 unconstrained. But remove any padding from the resulting type. */
454 {
459 }
461 /* We always want to return the underlying INTEGER_CST for an enumeration
462 literal to avoid the need to call fold in lots of places. But don't do
463 this is the parent will be taking the address of this object. */
465 {
479 }
483 }
484 \f
485 /* Subroutine of gnat_to_gnu to process gnat_node, an N_Pragma. Return
486 any statements we generate. */
488 static tree
490 {
491 Node_Id gnat_temp;
494 /* Check for (and ignore) unrecognized pragma and do nothing if we are just
495 annotating types. */
500 {
502 /* Do nothing at top level: all such variables are already viewable. */
509 {
518 }
524 {
538 }
545 }
548 }
549 /* Subroutine of gnat_to_gnu to translate gnat_node, an N_Attribute,
550 to a GCC tree, which is returned. GNU_RESULT_TYPE_P is a pointer to
551 where we should place the result type. ATTRIBUTE is the attribute ID. */
553 static tree
555 {
557 tree gnu_result_type;
558 tree gnu_expr;
563 /* If the input is a NULL_EXPR, make a new one. */
565 {
569 }
572 {
575 /* These are just conversions until since representation clauses for
576 enumerations are handled in the front end. */
577 {
584 }
589 /* These just add or subject the constant 1. Representation clauses for
590 enumerations are handled in the front-end. */
595 {
597 gnu_expr
598 = emit_check
600 gnu_expr,
601 attribute == Attr_Pred
605 }
607 gnu_result
616 /* Conversions don't change something's address but can cause us to miss
617 the COMPONENT_REF case below, so strip them off. */
621 /* If we are taking 'Address of an unconstrained object, this is the
622 pointer to the underlying array. */
625 /* ... fall through ... */
631 gnu_result
638 /* For 'Code_Address, find an inner ADDR_EXPR and mark it so that we
639 don't try to build a trampoline. */
641 {
650 }
654 {
655 tree gnu_obj_type;
660 /* If this is an unconstrained array, we know the object must have been
661 allocated with the template in front of the object. So compute the
662 template address.*/
664 gnu_ptr
666 (TYPE_OBJECT_RECORD_TYPE
668 gnu_ptr);
673 {
676 tree gnu_byte_offset
683 }
686 }
695 /* Remove NOPS from gnu_expr and conversions from gnu_prefix.
696 We only use GNU_EXPR to see if a COMPONENT_REF was involved. */
699 ;
705 /* Replace an unconstrained array type with the type of the underlying
706 array. We can't do this with a call to maybe_unconstrained_array
707 since we may have a TYPE_DECL. For 'Max_Size_In_Storage_Elements,
708 use the record type that will be used to allocate the object and its
709 template. */
711 {
715 }
717 /* If we're looking for the size of a field, return the field size.
718 Otherwise, if the prefix is an object, or if 'Object_Size or
719 'Max_Size_In_Storage_Elements has been specified, the result is the
720 GCC size of the type. Otherwise, the result is the RM_Size of the
721 type. */
727 {
728 /* If this is a padded type, the GCC size isn't relevant to the
729 programmer. Normally, what we want is the RM_Size, which was set
730 from the specified size, but if it was not set, we want the size
731 of the relevant field. Using the MAX of those two produces the
732 right result in all case. Don't use the size of the field if it's
733 a self-referential type, since that's never what's wanted. */
737 {
741 gnu_result
744 }
745 else
747 }
748 else
754 /* Deal with a self-referential size by returning the maximum size for a
755 type and by qualifying the size with the object for 'Size of an
756 object. */
758 {
761 gnu_expr);
762 else
764 }
766 /* If the type contains a template, subtract its size. */
774 /* Always perform division using unsigned arithmetic as the size cannot
775 be negative, but may be an overflowed positive value. This provides
776 correct results for sizes up to 512 MB.
778 ??? Size should be calculated in storage elements directly. */
799 else
809 {
816 else
817 gnu_result
818 = build_binary_op
820 build_binary_op
832 }
834 /* ... fall through ... */
837 {
842 /* Make sure any implicit dereference gets done. */
850 {
852 tree gnu_type_temp;
858 ;
861 }
870 gnu_result
873 gnu_result
875 else
876 /* 'Length or 'Range_Length. */
877 {
878 tree gnu_compute_type
882 gnu_result
883 = build_binary_op
885 build_binary_op
887 build_binary_op
890 TYPE_MAX_VALUE
893 TYPE_MIN_VALUE
897 }
899 /* If this has a PLACEHOLDER_EXPR, qualify it by the object we are
900 handling. Note that these attributes could not have been used on
901 an unconstrained array type. */
903 gnu_prefix);
905 }
912 {
913 HOST_WIDE_INT bitsize;
914 HOST_WIDE_INT bitpos;
915 tree gnu_offset;
916 tree gnu_field_bitpos;
917 tree gnu_field_offset;
918 tree gnu_inner;
926 /* We can have 'Bit on any object, but if it isn't a COMPONENT_REF,
927 the result is 0. Don't allow 'Bit on a bare component, though. */
931 {
934 }
945 {
953 {
954 gnu_field_bitpos
957 gnu_field_offset
960 }
961 }
963 {
966 }
967 else
968 {
971 }
974 {
989 bitsize_one_node);
995 }
997 /* If this has a PLACEHOLDER_EXPR, qualify it by the object
998 we are handling. */
1001 }
1005 {
1013 }
1042 /* Note this size cannot be self-referential. */
1049 /* This is just a zero cast to the pointer type for
1050 our prefix and dereferenced. */
1052 gnu_result
1055 integer_zero_node));
1060 {
1067 {
1072 ;
1073 }
1081 && (DECL_BY_COMPONENT_PTR_P
1085 }
1089 /* Say we have an unimplemented attribute. Then set the value to be
1090 returned to be a zero and hope that's something we can convert to the
1091 type of this attribute. */
1096 }
1098 /* If this is an attribute where the prefix was unused, force a use of it if
1099 it has a side-effect. But don't do it if the prefix is just an entity
1100 name. However, if an access check is needed, we must do it. See second
1101 example in AARM 11.6(5.e). */
1109 }
1110 \f
1111 /* Subroutine of gnat_to_gnu to translate gnat_node, an N_Case_Statement,
1112 to a GCC tree, which is returned. */
1114 static tree
1116 {
1117 tree gnu_result;
1118 tree gnu_expr;
1119 Node_Id gnat_when;
1124 /* The range of values in a case statement is determined by the rules in
1125 RM 5.4(7-9). In almost all cases, this range is represented by the Etype
1126 of the expression. One exception arises in the case of a simple name that
1127 is parenthesized. This still has the Etype of the name, but since it is
1128 not a name, para 7 does not apply, and we need to go to the base type.
1129 This is the only case where parenthesization affects the dynamic
1130 semantics (i.e. the range of possible values at runtime that is covered
1131 by the others alternative.
1133 Another exception is if the subtype of the expression is non-static. In
1134 that case, we also have to use the base type. */
1140 /* We build a SWITCH_EXPR that contains the code with interspersed
1141 CASE_LABEL_EXPRs for each label. */
1148 {
1149 Node_Id gnat_choice;
1151 /* First compile all the different case choices for the current WHEN
1152 alternative. */
1155 {
1159 {
1174 /* This represents either a subtype range or a static value of
1175 some kind; Ekind says which. If a static value, fall through
1176 to the next case. */
1178 {
1184 }
1186 /* ... fall through ... */
1198 }
1203 gnat_choice);
1204 }
1206 /* Push a binding level here in case variables are declared since we want
1207 them to be local to this set of statements instead of the block
1208 containing the Case statement. */
1212 }
1214 /* Now emit a definition of the label all the cases branched to. */
1222 }
1223 \f
1224 /* Subroutine of gnat_to_gnu to translate gnat_node, an N_Loop_Statement,
1225 to a GCC tree, which is returned. */
1227 static tree
1229 {
1230 /* ??? It would be nice to use "build" here, but there's no build5. */
1236 tree gnu_result;
1243 /* Save the end label of this LOOP_STMT in a stack so that the corresponding
1244 N_Exit_Statement can find it. */
1248 /* Set the condition that under which the loop should continue.
1249 For "LOOP .... END LOOP;" the condition is always true. */
1251 ;
1252 /* The case "WHILE condition LOOP ..... END LOOP;" */
1256 else
1257 {
1258 /* We have an iteration scheme. */
1273 /* We know the loop variable will not overflow if GNU_LAST is a constant
1274 and is not equal to GNU_LIMIT. If it might overflow, we have to move
1275 the limit test to the end of the loop. In that case, we have to test
1276 for an empty loop outside the loop. */
1280 {
1281 gnu_cond_expr
1287 }
1289 /* Open a new nesting level that will surround the loop to declare the
1290 loop index variable. */
1294 /* Declare the loop index and set it to its initial value. */
1299 /* The loop variable might be a padded type, so use `convert' to get a
1300 reference to the inner variable if so. */
1303 /* Set either the top or bottom exit condition as appropriate depending
1304 on whether or not we know an overflow cannot occur. */
1309 else
1318 gnu_loop_var,
1320 integer_one_node));
1322 gnat_iter_scheme);
1323 }
1325 /* If the loop was named, have the name point to this loop. In this case,
1326 the association is not a ..._DECL node, but the end label from this
1327 LOOP_STMT. */
1332 /* Make the loop body into its own block, so any allocated storage will be
1333 released every iteration. This is needed for stack allocation. */
1337 /* If we declared a variable, then we are in a statement group for that
1338 declaration. Add the LOOP_STMT to it and make that the "loop". */
1340 {
1344 }
1346 /* If we have an outer COND_EXPR, that's our result and this loop is its
1347 "true" statement. Otherwise, the result is the LOOP_STMT. */
1349 {
1353 }
1354 else
1360 }
1361 \f
1362 /* Subroutine of gnat_to_gnu to process gnat_node, an N_Subprogram_Body. We
1363 don't return anything. */
1365 static void
1367 {
1368 /* Save debug output mode in case it is reset. */
1371 /* Definining identifier of a parameter to the subprogram. */
1372 Entity_Id gnat_param;
1373 /* The defining identifier for the subprogram body. Note that if a
1374 specification has appeared before for this body, then the identifier
1375 occurring in that specification will also be a defining identifier and all
1376 the calls to this subprogram will point to that specification. */
1377 Entity_Id gnat_subprog_id
1380 /* The FUNCTION_DECL node corresponding to the subprogram spec. */
1381 tree gnu_subprog_decl;
1382 /* The FUNCTION_TYPE node corresponding to the subprogram spec. */
1383 tree gnu_subprog_type;
1384 tree gnu_cico_list;
1385 tree gnu_result;
1387 /* If this is a generic object or if it has been eliminated,
1388 ignore it. */
1394 /* If debug information is suppressed for the subprogram, turn debug
1395 mode off for the duration of processing. */
1397 {
1400 }
1402 /* If this subprogram acts as its own spec, define it. Otherwise, just get
1403 the already-elaborated tree node. However, if this subprogram had its
1404 elaboration deferred, we will already have made a tree node for it. So
1405 treat it as not being defined in that case. Such a subprogram cannot
1406 have an address clause or a freeze node, so this test is safe, though it
1407 does disable some otherwise-useful error checking. */
1408 gnu_subprog_decl
1415 /* Set the line number in the decl to correspond to that of the body so that
1416 the line number notes are written
1417 correctly. */
1423 /* If there are OUT parameters, we need to ensure that the return statement
1424 properly copies them out. We do this by making a new block and converting
1425 any inner return into a goto to a label at the end of the block. */
1429 /* Get a tree corresponding to the code for the subprogram. */
1433 /* See if there are any parameters for which we don't yet have GCC entities.
1434 These must be for OUT parameters for which we will be making VAR_DECL
1435 nodes here. Fill them in to TYPE_CI_CO_LIST, which must contain the empty
1436 entry as well. We can match up the entries because TYPE_CI_CO_LIST is in
1437 the order of the parameters. */
1442 {
1443 /* Skip any entries that have been already filled in; they must
1444 correspond to IN OUT parameters. */
1447 ;
1449 /* Do any needed references for padded types. */
1453 }
1457 /* Generate the code of the subprogram itself. A return statement will be
1458 present and any OUT parameters will be handled there. */
1463 /* If we made a special return label, we need to make a block that contains
1464 the definition of that label and the copying to the return value. That
1465 block first contains the function, then the label and copy statement. */
1467 {
1468 tree gnu_retval;
1479 else
1481 gnu_cico_list);
1486 add_stmt_with_node
1490 gnat_node);
1493 }
1497 /* Initialize the information node for the function and set the
1498 end location. */
1500 Sloc_to_locus
1508 /* Disconnect the trees for parameters that we made variables for from the
1509 GNAT entities since these are unusable after we end the function. */
1519 }
1520 \f
1521 /* Subroutine of gnat_to_gnu to translate gnat_node, either an N_Function_Call
1522 or an N_Procedure_Call_Statement, to a GCC tree, which is returned.
1523 GNU_RESULT_TYPE_P is a pointer to where we should place the result type.
1524 If GNU_TARGET is non-null, this must be a function call and the result
1525 of the call is to be placed into that object. */
1527 static tree
1529 {
1530 tree gnu_result;
1531 /* The GCC node corresponding to the GNAT subprogram name. This can either
1532 be a FUNCTION_DECL node if we are dealing with a standard subprogram call,
1533 or an indirect reference expression (an INDIRECT_REF node) pointing to a
1534 subprogram. */
1536 /* The FUNCTION_TYPE node giving the GCC type of the subprogram. */
1539 gnu_subprog_node);
1540 Entity_Id gnat_formal;
1541 Node_Id gnat_actual;
1546 tree gnu_subprog_call;
1549 {
1556 }
1561 /* If we are calling a stubbed function, make this into a raise of
1562 Program_Error. Elaborate all our args first. */
1565 {
1572 {
1576 }
1577 else
1579 }
1581 /* If we are calling by supplying a pointer to a target, set up that
1582 pointer as the first argument. Use GNU_TARGET if one was passed;
1583 otherwise, make a target by building a variable of the maximum size
1584 of the type. */
1586 {
1587 tree gnu_real_ret_type
1591 {
1592 tree gnu_obj_type
1600 }
1602 gnu_actual_list
1606 gnu_target,
1608 NULL_TREE);
1610 }
1612 /* The only way we can be making a call via an access type is if Name is an
1613 explicit dereference. In that case, get the list of formal args from the
1614 type the access type is pointing to. Otherwise, get the formals from
1615 entity being called. */
1619 /* Assume here that this must be 'Elab_Body or 'Elab_Spec. */
1621 else
1624 /* Create the list of the actual parameters as GCC expects it, namely a chain
1625 of TREE_LIST nodes in which the TREE_VALUE field of each node is a
1626 parameter-expression and the TREE_PURPOSE field is null. Skip OUT
1627 parameters not passed by reference and don't need to be copied in. */
1632 {
1634 /* We treat a conversion between aggregate types as if it is an
1635 unchecked conversion. */
1636 bool unchecked_convert_p
1640 Node_Id gnat_name = (unchecked_convert_p
1644 tree gnu_formal
1647 tree gnu_actual;
1649 /* If it's possible we may need to use this expression twice, make sure
1650 than any side-effects are handled via SAVE_EXPRs. Likewise if we need
1651 to force side-effects before the call.
1653 ??? This is more conservative than we need since we don't need to do
1654 this for pass-by-ref with no conversion. If we are passing a
1655 non-addressable Out or In Out parameter by reference, pass the address
1656 of a copy and set up to copy back out after the call. */
1658 {
1661 && gnu_formal
1666 {
1668 tree gnu_temp;
1670 /* Remove any unpadding on the actual and make a copy. But if
1671 the actual is a left-justified modular type, first convert
1672 to it. */
1676 && (TYPE_IS_PADDING_P
1685 /* Since we're going to take the address of the SAVE_EXPR, we
1686 don't want it to be marked as unchanging. So set
1687 TREE_ADDRESSABLE. */
1690 {
1693 }
1695 /* Set up to move the copy back to the original. */
1700 }
1701 }
1703 /* If this was a procedure call, we may not have removed any padding.
1704 So do it here for the part we will use as an input, if any. */
1710 gnu_actual);
1712 /* Unless this is an In parameter, we must remove any LJM building
1713 from GNU_NAME. */
1719 gnu_name);
1722 && !unchecked_convert_p
1726 /* Do any needed conversions. We need only check for unchecked
1727 conversion since normal conversions will be handled by just
1728 converting to the formal type. */
1730 {
1731 gnu_actual
1733 gnu_actual,
1738 /* One we've done the unchecked conversion, we still must ensure that
1739 the object is in range of the formal's type. */
1744 }
1746 /* We may have suppressed a conversion to the Etype of the actual since
1747 the parent is a procedure call. So add the conversion here. */
1749 gnu_actual);
1754 /* If we have not saved a GCC object for the formal, it means it is an
1755 OUT parameter not passed by reference and that does not need to be
1756 copied in. Otherwise, look at the PARM_DECL to see if it is passed by
1757 reference. */
1760 {
1762 {
1765 /* If we have a padded type, be sure we've removed padding. */
1770 gnu_actual);
1771 }
1773 /* Otherwise, if we have a non-addressable COMPONENT_REF of a
1774 variable-size type see if it's doing a unpadding operation. If
1775 so, remove that operation since we have no way of allocating the
1776 required temporary. */
1786 /* The symmetry of the paths to the type of an entity is broken here
1787 since arguments don't know that they will be passed by ref. */
1790 }
1793 {
1800 {
1803 }
1805 /* Take the address of the object and convert to the proper pointer
1806 type. We'd like to actually compute the address of the beginning
1807 of the array using an ADDR_EXPR of an ARRAY_REF, but there's a
1808 possibility that the ARRAY_REF might return a constant and we'd be
1809 getting the wrong address. Neither approach is exactly correct,
1810 but this is the most likely to work in all cases. */
1813 gnu_actual));
1814 }
1817 {
1818 /* If arg is 'Null_Parameter, pass zero descriptor. */
1823 integer_zero_node);
1824 else
1827 gnat_formal));
1828 }
1829 else
1830 {
1839 /* If this is 'Null_Parameter, pass a zero even though we are
1840 dereferencing it. */
1845 BITS_PER_WORD))
1846 gnu_actual
1851 integer_zero_node),
1853 else
1854 gnu_actual
1856 gnu_actual);
1857 }
1860 }
1864 NULL_TREE);
1866 /* If we return by passing a target, we emit the call and return the target
1867 as our result. */
1869 {
1871 *gnu_result_type_p
1874 }
1876 /* If it is a function call, the result is the call expression unless
1877 a target is specified, in which case we copy the result into the target
1878 and return the assignment statement. */
1880 {
1883 /* If the function returns an unconstrained array or by reference,
1884 we have to de-dereference the pointer. */
1892 else
1896 }
1898 /* If this is the case where the GNAT tree contains a procedure call
1899 but the Ada procedure has copy in copy out parameters, the special
1900 parameter passing mechanism must be used. */
1902 {
1903 /* List of FIELD_DECLs associated with the PARM_DECLs of the copy
1904 in copy out parameters. */
1909 {
1910 tree gnu_name;
1915 /* If any of the names had side-effects, ensure they are all
1916 evaluated before the call. */
1922 }
1926 else
1933 /* If we are dealing with a copy in copy out parameter, we must
1934 retrieve its value from the record returned in the call. */
1940 || (DECL_BY_DESCRIPTOR_P
1943 {
1944 /* Get the value to assign to this OUT or IN OUT parameter. It is
1945 either the result of the function if there is only a single such
1946 parameter or the appropriate field from the record returned. */
1947 tree gnu_result
1954 /* If the actual is a conversion, get the inner expression, which
1955 will be the real destination, and convert the result to the
1956 type of the actual parameter. */
1957 tree gnu_actual
1960 /* If the result is a padded type, remove the padding. */
1965 gnu_result);
1967 /* If the result is a type conversion, do it. */
1969 gnu_result
1970 = convert_with_check
1978 gnu_result,
1980 else
1981 {
1989 }
1997 }
1998 }
1999 else
2000 {
2003 }
2007 }
2008 \f
2009 /* Subroutine of gnat_to_gnu to translate gnat_node, an
2010 N_Handled_Sequence_Of_Statements, to a GCC tree, which is returned. */
2012 static tree
2014 {
2017 /* If just annotating, ignore all EH and cleanups. */
2021 bool setjmp_longjmp
2027 tree gnu_result;
2028 tree gnu_expr;
2029 Node_Id gnat_temp;
2031 /* The GCC exception handling mechanism can handle both ZCX and SJLJ schemes
2032 and we have our own SJLJ mechanism. To call the GCC mechanism, we call
2033 add_cleanup, and when we leave the binding, end_stmt_group will create
2034 the TRY_FINALLY_EXPR.
2036 ??? The region level calls down there have been specifically put in place
2037 for a ZCX context and currently the order in which things are emitted
2038 (region/handlers) is different from the SJLJ case. Instead of putting
2039 other calls with different conditions at other places for the SJLJ case,
2040 it seems cleaner to reorder things for the SJLJ case and generalize the
2041 condition to make it not ZCX specific.
2043 If there are any exceptions or cleanup processing involved, we need an
2044 outer statement group (for Setjmp_Longjmp) and binding level. */
2046 {
2049 }
2051 /* If we are to call a function when exiting this block add a cleanup
2052 to the binding level we made above. */
2056 /* If using setjmp_longjmp, make the variables for the setjmp buffer and save
2057 area for address of previous buffer. Do this first since we need to have
2058 the setjmp buf known for any decls in this block. */
2060 {
2065 gnat_node);
2073 /* When we exit this block, restore the saved value. */
2075 }
2077 /* Now build the tree for the declarations and statements inside this block.
2078 If this is SJLJ, set our jmp_buf as the current buffer. */
2084 gnu_jmpbuf_decl)));
2091 /* Generate code for each statement in the block. */
2099 /* Now generate code for the two exception models, if either is relevant for
2100 this block. */
2102 {
2104 tree gnu_handler;
2106 /* Make a binding level for the exception handling declarations and code
2107 and set up gnu_except_ptr_stack for the handlers to use. */
2113 NULL_TREE,
2118 /* Generate code for each handler. The N_Exception_Handler case does the
2119 real work and returns a COND_EXPR for each handler, which we chain
2120 together here. */
2123 {
2126 /* If this is the first one, set it as the outer one. Otherwise,
2127 point the "else" part of the previous handler to us. Then point
2128 to our "else" part. */
2131 else
2135 }
2137 /* If none of the exception handlers did anything, re-raise but do not
2138 defer abortion. */
2145 else
2148 /* End the binding level dedicated to the exception handlers and get the
2149 whole statement group. */
2154 /* If the setjmp returns 1, we restore our incoming longjmp value and
2155 then check the handlers. */
2158 gnu_jmpsave_decl),
2159 gnat_node);
2163 /* This block is now "if (setjmp) ... <handlers> else <block>". */
2165 (build_call_1_expr
2168 gnu_jmpbuf_decl))),
2170 }
2172 {
2173 tree gnu_handlers;
2175 /* First make a block containing the handlers. */
2183 /* Now make the TRY_CATCH_EXPR for the block. */
2186 }
2187 else
2190 /* Now close our outer block, if we had to make one. */
2192 {
2196 }
2199 }
2200 \f
2201 /* Subroutine of gnat_to_gnu to translate gnat_node, an N_Exception_Handler,
2202 to a GCC tree, which is returned. This is the variant for Setjmp_Longjmp
2203 exception handling. */
2205 static tree
2207 {
2208 /* Unless this is "Others" or the special "Non-Ada" exception for Ada, make
2209 an "if" statement to select the proper exceptions. For "Others", exclude
2210 exceptions where Handled_By_Others is nonzero unless the All_Others flag
2211 is set. For "Non-ada", accept an exception if "Lang" is 'V'. */
2214 Node_Id gnat_temp;
2218 {
2219 tree this_choice;
2222 {
2225 else
2226 this_choice
2227 = build_binary_op
2229 convert
2231 build_component_ref
2232 (build_unary_op
2237 integer_zero_node);
2238 }
2242 {
2243 tree gnu_expr
2246 this_choice
2247 = build_binary_op
2252 /* If this is the distinguished exception "Non_Ada_Error" (and we are
2253 in VMS mode), also allow a non-Ada exception (a VMS condition) t
2254 match. */
2256 {
2257 tree gnu_comp
2258 = build_component_ref
2263 this_choice
2264 = build_binary_op
2268 this_choice);
2269 }
2270 }
2271 else
2276 }
2279 }
2280 \f
2281 /* Subroutine of gnat_to_gnu to translate gnat_node, an N_Exception_Handler,
2282 to a GCC tree, which is returned. This is the variant for ZCX. */
2284 static tree
2286 {
2288 tree gnu_expr;
2289 tree gnu_etype;
2290 tree gnu_current_exc_ptr;
2291 tree gnu_incoming_exc_ptr;
2292 Node_Id gnat_temp;
2294 /* We build a TREE_LIST of nodes representing what exception types this
2295 handler can catch, with special cases for others and all others cases.
2297 Each exception type is actually identified by a pointer to the exception
2298 id, with special value zero for "others" and one for "all others". Beware
2299 that these special values are known and used by the personality routine to
2300 identify the corresponding specific kinds of handlers.
2302 ??? For initial time frame reasons, the others and all_others cases have
2303 been handled using specific type trees, but this somehow hides information
2304 from the back-end, which expects NULL to be passed for catch all and
2305 end_cleanup to be used for cleanups.
2307 Care should be taken to ensure that the control flow impact of such
2308 clauses is rendered in some way. lang_eh_type_covers is doing the trick
2309 currently. */
2312 {
2318 {
2321 /* Exception may be a renaming. Recover original exception which is
2322 the one elaborated and registered. */
2329 /* The Non_Ada_Error case for VMS exceptions is handled
2330 by the personality routine. */
2331 }
2332 else
2335 /* The GCC interface expects NULL to be passed for catch all handlers, so
2336 it would be quite tempting to set gnu_etypes_list to NULL if gnu_etype
2337 is integer_zero_node. It would not work, however, because GCC's
2338 notion of "catch all" is stronger than our notion of "others". Until
2339 we correctly use the cleanup interface as well, doing that would
2340 prevent the "all others" handlers from beeing seen, because nothing
2341 can be caught beyond a catch all from GCC's point of view. */
2343 }
2348 /* Expand a call to the begin_handler hook at the beginning of the handler,
2349 and arrange for a call to the end_handler hook to occur on every possible
2350 exit path.
2352 The hooks expect a pointer to the low level occurrence. This is required
2353 for our stack management scheme because a raise inside the handler pushes
2354 a new occurrence on top of the stack, which means that this top does not
2355 necessarily match the occurrence this handler was dealing with.
2357 The EXC_PTR_EXPR object references the exception occurrence being
2358 propagated. Upon handler entry, this is the exception for which the
2359 handler is triggered. This might not be the case upon handler exit,
2360 however, as we might have a new occurrence propagated by the handler's
2361 body, and the end_handler hook called as a cleanup in this context.
2363 We use a local variable to retrieve the incoming value at handler entry
2364 time, and reuse it to feed the end_handler hook's argument at exit. */
2369 gnat_node);
2372 gnu_incoming_exc_ptr),
2373 gnat_node);
2380 }
2381 \f
2382 /* Subroutine of gnat_to_gnu to generate code for an N_Compilation unit. */
2384 static void
2386 {
2387 /* Make the decl for the elaboration procedure. */
2392 tree gnu_elab_proc_decl
2393 = create_subprog_decl
2397 gnat_unit_entity);
2407 /* For a body, first process the spec if there is one. */
2416 {
2423 }
2429 /* Process any pragmas and actions following the unit. */
2433 /* Save away what we've made so far and record this potential elaboration
2434 procedure. */
2444 /* Generate elaboration code for this unit, if necessary, and say whether
2445 we did or not. */
2447 }
2448 \f
2449 /* This function is the driver of the GNAT to GCC tree transformation
2450 process. It is the entry point of the tree transformer. GNAT_NODE is the
2451 root of some GNAT tree. Return the root of the corresponding GCC tree.
2452 If this is an expression, return the GCC equivalent of the expression. If
2453 it is a statement, return the statement. In the case when called for a
2454 statement, it may also add statements to the current statement group, in
2455 which case anything it returns is to be interpreted as occuring after
2456 anything `it already added. */
2458 tree
2460 {
2464 tree gnu_expr;
2466 Node_Id gnat_temp;
2468 /* Save node number for error message and set location information. */
2476 /* If this node is a non-static subexpression and we are only
2477 annotating types, make this into a NULL_EXPR. */
2485 /* If this is a Statement and we are at top level, it must be part of
2486 the elaboration procedure, so mark us as being in that procedure
2487 and push our context. */
2499 {
2504 }
2507 {
2508 /********************************/
2509 /* Chapter 2: Lexical Elements: */
2510 /********************************/
2520 {
2521 tree gnu_type;
2523 /* Get the type of the result, looking inside any padding and
2524 left-justified modular types. Then get the value in that type. */
2533 /* If the result overflows (meaning it doesn't fit in its base type),
2534 abort. We would like to check that the value is within the range
2535 of the subtype, but that causes problems with subtypes whose usage
2536 will raise Constraint_Error and with biased representation, so
2537 we don't. */
2540 }
2544 /* If a Entity is present, it means that this was one of the
2545 literals in a user-defined character type. In that case,
2546 just return the value in the CONST_DECL. Otherwise, use the
2547 character code. In that case, the base type should be an
2548 INTEGER_TYPE, but we won't bother checking for that. */
2552 else
2553 gnu_result
2554 = force_fit_type
2560 /* If this is of a fixed-point type, the value we want is the
2561 value of the corresponding integer. */
2563 {
2566 gnu_result_type);
2569 }
2571 /* We should never see a Vax_Float type literal, since the front end
2572 is supposed to transform these using appropriate conversions */
2576 else
2577 {
2582 /* If the real value is zero, so is the result. Otherwise,
2583 convert it to a machine number if it isn't already. That
2584 forces BASE to 0 or 2 and simplifies the rest of our logic. */
2587 else
2588 {
2590 ur_realval
2594 gnu_result
2597 /* If we have a base of zero, divide by the denominator.
2598 Otherwise, the base must be 2 and we scale the value, which
2599 we know can fit in the mantissa of the type (hence the use
2600 of that type above). */
2602 gnu_result
2605 gnu_result,
2607 gnu_result_type));
2611 else
2612 {
2613 REAL_VALUE_TYPE tmp;
2618 }
2619 }
2621 /* Now see if we need to negate the result. Do it this way to
2622 properly handle -0. */
2624 gnu_result
2626 gnu_result);
2627 }
2634 {
2640 /* Build the string with the characters in the literal. Note
2641 that Ada strings are 1-origin. */
2645 /* Put a null at the end of the string in case it's in a context
2646 where GCC will want to treat it as a C string. */
2651 /* Strings in GCC don't normally have types, but we want
2652 this to not be converted to the array type. */
2654 }
2655 else
2656 {
2657 /* Build a list consisting of each character, then make
2658 the aggregate. */
2666 {
2667 gnu_list
2672 gnu_list);
2676 }
2678 gnu_result
2680 }
2687 /**************************************/
2688 /* Chapter 3: Declarations and Types: */
2689 /**************************************/
2706 /* If we are just annotating types and this object has an unconstrained
2707 or task type, don't elaborate it. */
2718 && (!type_annotate_only
2720 {
2725 /* If this object has its elaboration delayed, we must force
2726 evaluation of GNU_EXPR right now and save it for when the object
2727 is frozen. */
2729 {
2732 gnu_expr
2737 else
2741 }
2742 }
2743 else
2756 /* Don't do anything if this renaming is handled by the front end. or if
2757 we are just annotating types and this object has a composite or task
2758 type, don't elaborate it. We return the result in case it has any
2759 SAVE_EXPRs in it that need to be evaluated here. */
2761 && ! (type_annotate_only
2765 gnu_result
2768 else
2781 /* These are fully handled in the front end. */
2785 /*************************************/
2786 /* Chapter 4: Names and Expressions: */
2787 /*************************************/
2796 {
2798 tree gnu_type;
2806 /* If we got a padded type, remove it too. */
2809 gnu_array_object
2811 gnu_array_object);
2815 /* First compute the number of dimensions of the array, then
2816 fill the expression array, the order depending on whether
2817 this is a Convention_Fortran array or not. */
2822 ;
2831 else
2839 {
2847 gnu_expr
2848 = emit_index_check
2855 }
2856 }
2862 {
2863 tree gnu_type;
2869 /* Do any implicit dereferences of the prefix and do any needed
2870 range check. */
2875 {
2876 /* Get the bounds of the slice. */
2877 tree gnu_index_type
2883 /* Check to see that the minimum slice value is in range */
2884 gnu_expr_l
2885 = emit_index_check
2890 /* Check to see that the maximum slice value is in range */
2891 gnu_expr_h
2892 = emit_index_check
2897 /* Derive a good type to convert everything too */
2900 /* Build a compound expression that does the range checks */
2901 gnu_expr
2906 /* Build a conditional expression that returns the range checks
2907 expression if the slice range is not null (max >= min) or
2908 returns the min if the slice range is null */
2909 gnu_expr
2913 gnu_max_expr),
2915 gnu_min_expr)),
2917 }
2918 else
2923 }
2927 {
2931 tree gnu_field;
2935 {
2940 }
2944 /* For discriminant references in tagged types always substitute the
2945 corresponding discriminant as the actual selected component. */
2951 /* For discriminant references of untagged types always substitute the
2952 corresponding stored discriminant. */
2957 /* Handle extracting the real or imaginary part of a complex.
2958 The real part is the first field and the imaginary the last. */
2964 else
2965 {
2968 /* If there are discriminants, the prefix might be
2969 evaluated more than once, which is a problem if it has
2970 side-effects. */
2977 gnu_result
2981 }
2987 }
2991 {
2992 /* The attribute designator (like an enumeration value). */
2995 /* The Elab_Spec and Elab_Body attributes are special in that
2996 Prefix is a unit, not an object with a GCC equivalent. Similarly
2997 for Elaborated, since that variable isn't otherwise known. */
3001 attribute == Attr_Elab_Body
3004 gnat_node));
3007 }
3011 /* Like 'Access as far as we are concerned. */
3019 {
3020 tree gnu_aggr_type;
3022 /* ??? It is wrong to evaluate the type now, but there doesn't
3023 seem to be any other practical way of doing it. */
3025 gnu_aggr_type = gnu_result_type
3030 gnu_aggr_type
3037 gnu_result
3039 gnu_aggr_type);
3041 {
3042 /* The first element is the discrimant, which we ignore. The
3043 next is the field we're building. Convert the expression
3044 to the type of the field and then to the union type. */
3045 Node_Id gnat_assoc
3048 tree gnu_field_type
3053 }
3056 gnu_aggr_type,
3059 gnu_result
3060 = build_binary_op
3065 (Next
3067 else
3071 }
3081 /* Get the operand expression. */
3085 gnu_result
3097 /* If the result is a pointer type, see if we are improperly
3098 converting to a stricter alignment. */
3102 {
3108 post_error_ne_tree_2
3112 }
3120 {
3123 tree gnu_low;
3124 tree gnu_high;
3126 /* GNAT_RANGE is either an N_Range node or an identifier
3127 denoting a subtype. */
3129 {
3132 }
3135 {
3140 }
3141 else
3146 /* If LOW and HIGH are identical, perform an equality test.
3147 Otherwise, ensure that GNU_OBJECT is only evaluated once
3148 and perform a full range test. */
3152 else
3153 {
3155 gnu_result
3161 }
3165 }
3173 ? RDIV_EXPR
3180 /* These can either be operations on booleans or on modular types.
3181 Fall through for boolean types since that's the way GNU_CODES is
3182 set up. */
3184 Modular_Integer_Kind))
3185 {
3186 enum tree_code code
3197 }
3199 /* ... fall through ... */
3211 {
3213 tree gnu_type;
3219 /* If this is a comparison operator, convert any references to
3220 an unconstrained array value into a reference to the
3221 actual array. */
3223 {
3226 }
3228 /* If the result type is a private type, its full view may be a
3229 numeric subtype. The representation we need is that of its base
3230 type, given that it is the result of an arithmetic operation. */
3232 gnu_type = gnu_result_type
3235 /* If this is a shift whose count is not guaranteed to be correct,
3236 we need to adjust the shift count. */
3239 {
3241 tree gnu_max_shift
3249 gnu_rhs
3250 = build_binary_op
3253 gnu_count_type,
3254 gnu_max_shift,
3256 integer_one_node)),
3257 gnu_rhs);
3258 }
3260 /* For right shifts, the type says what kind of shift to do,
3261 so we may need to choose a different type. */
3270 {
3273 }
3277 /* If this is a logical shift with the shift count not verified,
3278 we must return zero if it is too large. We cannot compensate
3279 above in this case. */
3283 gnu_result
3284 = build_cond_expr
3287 gnu_rhs,
3291 gnu_result);
3292 }
3296 {
3299 tree gnu_false
3306 }
3315 /* This case can apply to a boolean or a modular type.
3316 Fall through for a boolean operand since GNU_CODES is set
3317 up to handle this. */
3319 {
3323 gnu_expr);
3325 }
3327 /* ... fall through ... */
3334 else
3343 {
3345 tree gnu_type;
3349 /* The Expression operand can either be an N_Identifier or
3350 Expanded_Name, which must represent a type, or a
3351 N_Qualified_Expression, which contains both the object type and an
3352 initial value for the object. */
3357 {
3358 Entity_Id gnat_desig_type
3369 {
3372 }
3373 else
3374 {
3380 }
3381 }
3382 else
3389 }
3392 /***************************/
3393 /* Chapter 5: Statements: */
3394 /***************************/
3406 /* Get the LHS and RHS of the statement and convert any reference to an
3407 unconstrained array into a reference to the underlying array.
3408 If we are not to do range checking and the RHS is an N_Function_Call,
3409 pass the LHS to the call function. */
3412 /* If the type has a size that overflows, convert this into raise of
3413 Storage_Error: execution shouldn't have gotten here anyway. */
3421 else
3422 {
3423 gnu_rhs
3426 /* If range check is needed, emit code to generate it */
3430 gnu_result
3432 }
3436 {
3439 /* Make the outer COND_EXPR. Avoid non-determinism. */
3448 /* Now make a COND_EXPR for each of the "else if" parts. Put each
3449 into the previous "else" part and point to where to put any
3450 outer "else". Also avoid non-determinism. */
3454 {
3464 }
3467 }
3491 gnu_result
3501 {
3502 /* The gnu function type of the subprogram currently processed. */
3504 /* The return value from the subprogram. */
3506 /* The place to put the return value. */
3507 tree gnu_lhs
3513 /* If we are dealing with a "return;" from an Ada procedure with
3514 parameters passed by copy in copy out, we need to return a record
3515 containing the final values of these parameters. If the list
3516 contains only one entry, return just that entry.
3518 For a full description of the copy in copy out parameter mechanism,
3519 see the part of the gnat_to_gnu_entity routine dealing with the
3520 translation of subprograms.
3522 But if we have a return label defined, convert this into
3523 a branch to that label. */
3526 {
3530 }
3533 {
3536 else
3537 gnu_ret_val
3540 }
3542 /* If the Ada subprogram is a function, we just need to return the
3543 expression. If the subprogram returns an unconstrained
3544 array, we have to allocate a new version of the result and
3545 return it. If we return by reference, return a pointer. */
3548 {
3549 /* If the current function returns by target pointer and we
3550 are doing a call, pass that target to the call. */
3556 else
3557 {
3560 /* Do not remove the padding from GNU_RET_VAL if the inner
3561 type is self-referential since we want to allocate the fixed
3562 size in that case. */
3566 && (TYPE_IS_PADDING_P
3568 && (CONTAINS_PLACEHOLDER_P
3574 gnu_ret_val
3578 {
3581 /* We have two cases: either the function returns with
3582 depressed stack or not. If not, we allocate on the
3583 secondary stack. If so, we allocate in the stack frame.
3584 if no copy is needed, the front end will set By_Ref,
3585 which we handle in the case above. */
3587 gnu_ret_val
3589 gnu_ret_val,
3592 else
3593 gnu_ret_val
3595 gnu_ret_val,
3599 gnat_node);
3600 }
3601 }
3606 {
3609 }
3610 }
3614 }
3622 /****************************/
3623 /* Chapter 6: Subprograms: */
3624 /****************************/
3627 /* Unless there is a freeze node, declare the subprogram. We consider
3628 this a "definition" even though we're not generating code for
3629 the subprogram because we will be making the corresponding GCC
3630 node here. */
3639 /* This subprogram doesn't exist for code generation purposes, but we
3640 have to elaborate the types of any parameters, unless they are
3641 imported types (nothing to generate in this case). */
3654 /* For a child unit identifier go up a level to get the
3655 specificaton. We get this when we try to find the spec of
3656 a child unit package that is the compilation unit being compiled. */
3670 /*************************/
3671 /* Chapter 7: Packages: */
3672 /*************************/
3688 /* If this is the body of a generic package - do nothing */
3690 {
3693 }
3704 /*********************************/
3705 /* Chapter 8: Visibility Rules: */
3706 /*********************************/
3710 /* Nothing to do here - but these may appear in list of declarations */
3714 /***********************/
3715 /* Chapter 9: Tasks: */
3716 /***********************/
3727 /***********************************************************/
3728 /* Chapter 10: Program Structure and Compilation Issues: */
3729 /***********************************************************/
3733 /* This is not called for the main unit, which is handled in function
3734 gigi above. */
3746 /* Simply process whatever unit is being inserted. */
3754 /***************************/
3755 /* Chapter 11: Exceptions: */
3756 /***************************/
3759 /* If there is an At_End procedure attached to this node, and the EH
3760 mechanism is SJLJ, we must have at least a corresponding At_End
3761 handler, unless the No_Exception_Handlers restriction is set. */
3777 else
3782 /*******************************/
3783 /* Chapter 12: Generic Units: */
3784 /*******************************/
3794 /* These nodes can appear on a declaration list but there is nothing to
3795 to be done with them. */
3799 /***************************************************/
3800 /* Chapter 13: Representation Clauses and */
3801 /* Implementation-Dependent Features: */
3802 /***************************************************/
3808 /* The only one we need deal with is for 'Address. For the others, SEM
3809 puts the information elsewhere. We need only deal with 'Address
3810 if the object has a Freeze_Node (which it never will currently). */
3815 /* Get the value to use as the address and save it as the
3816 equivalent for GNAT_TEMP. When the object is frozen,
3817 gnat_to_gnu_entity will do the right thing. */
3825 /* We do nothing with these. SEM puts the information elsewhere. */
3831 {
3837 /* First process inputs, then outputs, then clobbers. */
3840 {
3845 gnu_input_list
3848 }
3852 {
3857 gnu_output_list
3860 }
3864 gnu_clobber_list
3867 gnu_clobber_list);
3875 }
3876 else
3881 /***************************************************/
3882 /* Added Nodes */
3883 /***************************************************/
3901 {
3903 tree gnu_obj_type;
3904 tree gnu_obj_size;
3907 /* If this is a thin pointer, we must dereference it to create
3908 a fat pointer, then go back below to a thin pointer. The
3909 reason for this is that we need a fat pointer someplace in
3910 order to properly compute the size. */
3914 gnu_ptr));
3916 /* If this is an unconstrained array, we know the object must
3917 have been allocated with the template in front of the object.
3918 So pass the template address, but get the total size. Do this
3919 by converting to a thin pointer. */
3921 gnu_ptr
3923 (TYPE_OBJECT_RECORD_TYPE
3925 gnu_ptr);
3933 {
3936 tree gnu_byte_offset
3943 }
3948 gnat_node);
3949 }
3956 {
3959 }
3964 /* If the type is VOID, this is a statement, so we need to
3965 generate the code for the call. Handle a Condition, if there
3966 is one. */
3968 {
3975 }
3976 else
3981 /* If the result is a pointer type, see if we are either converting
3982 from a non-pointer or from a pointer to a type with a different
3983 alias set and warn if so. If the result defined in the same unit as
3984 this unchecked convertion, we can allow this because we can know to
3985 make that type have alias set 0. */
3986 {
3997 {
3998 post_error_ne
4001 post_error
4003 gnat_node);
4004 post_error_ne
4007 }
4008 }
4023 }
4025 /* If we pushed our level as part of processing the elaboration routine,
4026 pop it back now. */
4028 {
4033 }
4035 /* Set the location information into the result. If we're supposed to
4036 return something of void_type, it means we have something we're
4037 elaborating for effect, so just return. */
4044 /* If the result is a constant that overflows, raise constraint error. */
4047 {
4050 gnu_result
4053 }
4055 /* If our result has side-effects and is of an unconstrained type,
4056 make a SAVE_EXPR so that we can be sure it will only be referenced
4057 once. Note we must do this before any conversions. */
4063 /* Now convert the result to the proper type. If the type is void or if
4064 we have no result, return error_mark_node to show we have no result.
4065 If the type of the result is correct or if we have a label (which doesn't
4066 have any well-defined type), return our result. Also don't do the
4067 conversion if the "desired" type involves a PLACEHOLDER_EXPR in its size
4068 since those are the cases where the front end may have the type wrong due
4069 to "instantiating" the unconstrained record with discriminant values
4070 or if this is a FIELD_DECL. If this is the Name of an assignment
4071 statement or a parameter of a procedure call, return what we have since
4072 the RHS has to be converted to our type there in that case, unless
4073 GNU_RESULT_TYPE has a simpler size. Similarly, if the two types are
4074 record types with the same name, the expression type has integral mode,
4075 and GNU_RESULT_TYPE BLKmode, don't convert. This will be the case when
4076 we are converting from a packable type to its actual type and we need
4077 those conversions to be NOPs in order for assignments into these types to
4078 work properly if the inner object is a bitfield and hence can't have
4079 its address taken. Finally, don't convert integral types that are the
4080 operand of an unchecked conversion since we need to ignore those
4081 conversions (for 'Valid). Otherwise, convert the result to the proper
4082 type. */
4102 && (CONTAINS_PLACEHOLDER_P
4106 {
4107 /* In this case remove padding only if the inner object is of
4108 self-referential size: in that case it must be an object of
4109 unconstrained type with a default discriminant. In other cases,
4110 we want to avoid copying too much data. */
4117 gnu_result);
4118 }
4134 {
4135 /* Remove any padding record, but do nothing more in this case. */
4139 gnu_result);
4140 }
4148 /* We don't need any NOP_EXPR or NON_LVALUE_EXPR on GNU_RESULT. */
4155 }
4156 \f
4157 /* Record the current code position in GNAT_NODE. */
4159 static void
4161 {
4166 }
4168 /* Insert the code for GNAT_NODE at the position saved for that node. */
4170 static void
4172 {
4175 }
4176 \f
4177 /* Start a new statement group chained to the previous group. */
4179 static void
4181 {
4184 /* First see if we can get one from the free list. */
4187 else
4193 }
4195 /* Add GNU_STMT to the current statement group. */
4197 void
4199 {
4202 /* If we're at top level, show everything in here is in use in case
4203 any of it is shared by a subprogram. */
4207 }
4209 /* Similar, but set the location of GNU_STMT to that of GNAT_NODE. */
4211 void
4213 {
4217 }
4219 /* Add a declaration statement for GNU_DECL to the current statement group.
4220 Get SLOC from Entity_Id. */
4222 void
4224 {
4225 tree gnu_stmt;
4227 /* If this is a variable that Gigi is to ignore, we may have been given
4228 an ERROR_MARK. So test for it. We also might have been given a
4229 reference for a renaming. So only do something for a decl. Also
4230 ignore a TYPE_DECL for an UNCONSTRAINED_ARRAY_TYPE. */
4236 /* If we are global, we don't want to actually output the DECL_EXPR for
4237 this decl since we already have evaluated the expressions in the
4238 sizes and positions as globals and doing it again would be wrong.
4239 But we do have to mark everything as used. */
4243 else
4244 {
4248 {
4252 }
4253 }
4255 /* If this is a DECL_EXPR for a variable with DECL_INITIAl set,
4256 there are two cases we need to handle here. */
4258 {
4262 /* If this is a DECL_EXPR for a variable with DECL_INITIAL set
4263 and decl has a padded type, convert it to the unpadded type so the
4264 assignment is done properly. */
4267 gnu_lhs
4270 /* Otherwise, if this is going into memory and the initializer isn't
4271 valid for the assembler and loader. Gimplification could do this,
4272 but would be run too late if -fno-unit-at-a-time. */
4279 {
4280 tree gnu_assign_stmt
4289 }
4290 }
4291 }
4293 /* Utility function to mark nodes with TREE_VISITED. Called from walk_tree.
4294 We use this to indicate all variable sizes and positions in global types
4295 may not be shared by any subprogram. */
4297 static tree
4299 {
4303 /* Don't mark a dummy type as visited because we want to mark its sizes
4304 and fields once it's filled in. */
4309 }
4311 /* Likewise, but to mark as unvisited. */
4313 static tree
4316 {
4320 }
4322 /* Add GNU_CLEANUP, a cleanup action, to the current code group. */
4324 static void
4326 {
4328 }
4330 /* Set the BLOCK node corresponding to the current code group to GNU_BLOCK. */
4332 void
4334 {
4339 }
4341 /* Return code corresponding to the current code group. It is normally
4342 a STATEMENT_LIST, but may also be a BIND_EXPR or TRY_FINALLY_EXPR if
4343 BLOCK or cleanups were set. */
4345 static tree
4347 {
4351 /* If this is a null list, allocate a new STATEMENT_LIST. Then, if there
4352 are cleanups, make a TRY_FINALLY_EXPR. Last, if there is a BLOCK,
4353 make a BIND_EXPR. Note that we nest in that because the cleanup may
4354 reference variables in the block. */
4366 /* Remove this group from the stack and add it to the free list. */
4372 }
4374 /* Add a list of statements from GNAT_LIST, a possibly-empty list of
4375 statements.*/
4377 static void
4379 {
4380 Node_Id gnat_node;
4386 }
4388 /* Build a tree from GNAT_LIST, a possibly-empty list of statements.
4389 If BINDING_P is true, push and pop a binding level around the list. */
4391 static tree
4393 {
4403 }
4404 \f
4405 /* Push and pop routines for stacks. We keep a free list around so we
4406 don't waste tree nodes. */
4408 static void
4410 {
4414 {
4419 }
4420 else
4424 }
4426 static void
4428 {
4434 }
4435 \f
4436 /* GNU_STMT is a statement. We generate code for that statement. */
4438 void
4440 {
4441 #if 0
4443 #endif
4446 {
4447 #if 0
4449 /* First write a volatile ASM_INPUT to prevent anything from being
4450 moved. */
4456 modifier);
4459 #endif
4463 }
4464 }
4465 \f
4466 /* Generate GIMPLE in place for the expression at *EXPR_P. */
4468 int
4470 {
4477 {
4479 /* If this is for a scalar, just make a VAR_DECL for it. If for
4480 an aggregate, get a null pointer of the appropriate type and
4481 dereference it. */
4485 integer_zero_node));
4486 else
4487 {
4490 }
4496 /* We should only do this if we are just elaborating for side-effects,
4497 but we can't know that yet. */
4502 /* If we're taking the address of a constant CONSTRUCTOR, force it to
4503 be put into static memory. We know it's going to be readonly given
4504 the semantics we have and it's required to be static memory in
4505 the case when the reference is in an elaboration procedure. */
4508 {
4509 tree new_var
4518 pre_p);
4522 }
4526 /* We have a kludge here. If the FIELD_DECL is from a fat pointer and is
4527 from an early dummy type, replace it with the proper FIELD_DECL. */
4530 {
4534 }
4536 /* ... fall through ... */
4540 }
4541 }
4543 /* Generate GIMPLE in place for the statement at *STMT_P. */
4545 static enum gimplify_status
4547 {
4551 {
4561 {
4565 /* Set to emit the statements of the loop. */
4568 /* We first emit the start label and then a conditional jump to
4569 the end label if there's a top condition, then the body of the
4570 loop, then a conditional branch to the end label, then the update,
4571 if any, and finally a jump to the start label and the definition
4572 of the end label. */
4574 gnu_start_label),
4575 stmt_p);
4582 void_type_node,
4583 gnu_end_label)),
4584 stmt_p);
4593 void_type_node,
4594 gnu_end_label)),
4595 stmt_p);
4601 gnu_start_label),
4602 stmt_p);
4604 gnu_end_label),
4605 stmt_p);
4607 }
4610 /* Build a statement to jump to the corresponding end label, then
4611 see if it needs to be conditional. */
4620 }
4621 }
4622 \f
4623 /* Force references to each of the entities in packages GNAT_NODE with's
4624 so that the debugging information for all of them are identical
4625 in all clients. Operate recursively on anything it with's, but check
4626 that we aren't elaborating something more than once. */
4628 /* The reason for this routine's existence is two-fold.
4629 First, with some debugging formats, notably MDEBUG on SGI
4630 IRIX, the linker will remove duplicate debugging information if two
4631 clients have identical debugguing information. With the normal scheme
4632 of elaboration, this does not usually occur, since entities in with'ed
4633 packages are elaborated on demand, and if clients have different usage
4634 patterns, the normal case, then the order and selection of entities
4635 will differ. In most cases however, it seems that linkers do not know
4636 how to eliminate duplicate debugging information, even if it is
4637 identical, so the use of this routine would increase the total amount
4638 of debugging information in the final executable.
4640 Second, this routine is called in type_annotate mode, to compute DDA
4641 information for types in withed units, for ASIS use */
4643 static void
4645 {
4648 /* Process each unit only once. As we trace the context of all relevant
4649 units transitively, including generic bodies, we may encounter the
4650 same generic unit repeatedly */
4655 /* Save entities in all context units. A body may have an implicit_with
4656 on its own spec, if the context includes a child unit, so don't save
4657 the spec twice. */
4665 {
4669 {
4686 }
4688 {
4689 Node_Id gnat_body
4692 /* Retrieve compilation unit node of generic body. */
4697 /* If body is available, elaborate its context. */
4700 }
4701 }
4705 }
4706 \f
4707 /* Do the processing of N_Freeze_Entity, GNAT_NODE. */
4709 static void
4711 {
4713 tree gnu_old;
4714 tree gnu_new;
4715 tree gnu_init
4720 /* If this is a package, need to generate code for the package. */
4722 {
4723 insert_code_for
4727 }
4729 /* Check for old definition after the above call. This Freeze_Node
4730 might be for one its Itypes. */
4731 gnu_old
4734 /* If this entity has an Address representation clause, GNU_OLD is the
4735 address, so discard it here. */
4739 /* Don't do anything for class-wide types they are always
4740 transformed into their root type. */
4746 /* Don't do anything for subprograms that may have been elaborated before
4747 their freeze nodes. This can happen, for example because of an inner call
4748 in an instance body. */
4755 /* If we have a non-dummy type old tree, we have nothing to do. Unless
4756 this is the public view of a private type whose full view was not
4757 delayed, this node was never delayed as it should have been.
4758 Also allow this to happen for concurrent types since we may have
4759 frozen both the Corresponding_Record_Type and this type. */
4763 {
4770 else
4772 }
4774 /* Reset the saved tree, if any, and elaborate the object or type for real.
4775 If there is a full declaration, elaborate it and copy the type to
4776 GNAT_ENTITY. Likewise if this is the record subtype corresponding to
4777 a class wide type or subtype. */
4779 {
4788 }
4792 {
4795 /* The above call may have defined this entity (the simplest example
4796 of this is when we have a private enumeral type since the bounds
4797 will have the public view. */
4803 }
4804 else
4807 /* If we've made any pointers to the old version of this type, we
4808 have to update them. */
4812 }
4813 \f
4814 /* Process the list of inlined subprograms of GNAT_NODE, which is an
4815 N_Compilation_Unit. */
4817 static void
4819 {
4820 Entity_Id gnat_entity;
4821 Node_Id gnat_body;
4823 /* If we can inline, generate RTL for all the inlined subprograms.
4824 Define the entity first so we set DECL_EXTERNAL. */
4829 {
4833 {
4834 /* ??? This really should always be Present. */
4838 gnat_body
4840 }
4843 {
4846 }
4847 }
4848 }
4849 \f
4850 /* Elaborate decls in the lists GNAT_DECLS and GNAT_DECLS2, if present.
4851 We make two passes, one to elaborate anything other than bodies (but
4852 we declare a function if there was no spec). The second pass
4853 elaborates the bodies.
4855 GNAT_END_LIST gives the element in the list past the end. Normally,
4856 this is Empty, but can be First_Real_Statement for a
4857 Handled_Sequence_Of_Statements.
4859 We make a complete pass through both lists if PASS1P is true, then make
4860 the second pass over both lists if PASS2P is true. The lists usually
4861 correspond to the public and private parts of a package. */
4863 static void
4866 {
4868 Node_Id gnat_decl;
4878 {
4879 /* For package specs, we recurse inside the declarations,
4880 thus taking the two pass approach inside the boundary. */
4888 /* Similarly for any declarations in the actions of a
4889 freeze node. */
4891 {
4894 }
4896 /* Package bodies with freeze nodes get their elaboration deferred
4897 until the freeze node, but the code must be placed in the right
4898 place, so record the code position now. */
4906 (Corresponding_Spec
4909 record_code_position
4912 /* We defer most subprogram bodies to the second pass. */
4914 {
4916 {
4922 }
4923 }
4924 /* For bodies and stubs that act as their own specs, the entity
4925 itself must be elaborated in the first pass, because it may
4926 be used in other declarations. */
4928 {
4929 Node_Id gnat_subprog_id =
4936 }
4938 /* Concurrent stubs stand for the corresponding subprogram bodies,
4939 which are deferred like other bodies. */
4942 ;
4943 else
4945 }
4947 /* Here we elaborate everything we deferred above except for package bodies,
4948 which are elaborated at their freeze nodes. Note that we must also
4949 go inside things (package specs and freeze nodes) the first pass did. */
4955 {
4971 }
4972 }
4973 \f
4974 /* Emit code for a range check. GNU_EXPR is the expression to be checked,
4975 GNAT_RANGE_TYPE the gnat type or subtype containing the bounds against
4976 which we have to check. */
4978 static tree
4980 {
4986 /* If GNU_EXPR has an integral type that is narrower than GNU_RANGE_TYPE,
4987 we can't do anything since we might be truncating the bounds. No
4988 check is needed in this case. */
4994 /* Checked expressions must be evaluated only once. */
4997 /* There's no good type to use here, so we might as well use
4998 integer_type_node. Note that the form of the check is
4999 (not (expr >= lo)) or (not (expr >= hi))
5000 the reason for this slightly convoluted form is that NaN's
5001 are not considered to be in range in the float case. */
5002 return emit_check
5004 invert_truthvalue
5008 invert_truthvalue
5012 gnu_high)))),
5014 }
5015 \f
5016 /* Emit code for an index check. GNU_ARRAY_OBJECT is the array object
5017 which we are about to index, GNU_EXPR is the index expression to be
5018 checked, GNU_LOW and GNU_HIGH are the lower and upper bounds
5019 against which GNU_EXPR has to be checked. Note that for index
5020 checking we cannot use the emit_range_check function (although very
5021 similar code needs to be generated in both cases) since for index
5022 checking the array type against which we are checking the indeces
5023 may be unconstrained and consequently we need to retrieve the
5024 actual index bounds from the array object itself
5025 (GNU_ARRAY_OBJECT). The place where we need to do that is in
5026 subprograms having unconstrained array formal parameters */
5028 static tree
5030 tree gnu_expr,
5031 tree gnu_low,
5032 tree gnu_high)
5033 {
5034 tree gnu_expr_check;
5036 /* Checked expressions must be evaluated only once. */
5039 /* Must do this computation in the base type in case the expression's
5040 type is an unsigned subtypes. */
5043 /* If GNU_LOW or GNU_HIGH are a PLACEHOLDER_EXPR, qualify them by
5044 the object we are handling. */
5048 /* There's no good type to use here, so we might as well use
5049 integer_type_node. */
5050 return emit_check
5053 gnu_expr_check,
5055 gnu_low)),
5057 gnu_expr_check,
5059 gnu_high))),
5061 }
5062 \f
5063 /* GNU_COND contains the condition corresponding to an access, discriminant or
5064 range check of value GNU_EXPR. Build a COND_EXPR that returns GNU_EXPR if
5065 GNU_COND is false and raises a CONSTRAINT_ERROR if GNU_COND is true.
5066 REASON is the code that says why the exception was raised. */
5068 static tree
5070 {
5071 tree gnu_call;
5072 tree gnu_result;
5076 /* Use an outer COMPOUND_EXPR to make sure that GNU_EXPR will get evaluated
5077 in front of the comparison in case it ends up being a SAVE_EXPR. Put the
5078 whole thing inside its own SAVE_EXPR so the inner SAVE_EXPR doesn't leak
5079 out. */
5083 gnu_expr));
5085 /* If GNU_EXPR has side effects, make the outer COMPOUND_EXPR and
5086 protect it. Otherwise, show GNU_RESULT has no side effects: we
5087 don't need to evaluate it just for the check. */
5089 gnu_result
5091 else
5094 /* ??? Unfortunately, if we don't put a SAVE_EXPR around this whole thing,
5095 we will repeatedly do the test. It would be nice if GCC was able
5096 to optimize this and only do it once. */
5098 }
5099 \f
5100 /* Return an expression that converts GNU_EXPR to GNAT_TYPE, doing
5101 overflow checks if OVERFLOW_P is nonzero and range checks if
5102 RANGE_P is nonzero. GNAT_TYPE is known to be an integral type.
5103 If TRUNCATE_P is nonzero, do a float to integer conversion with
5104 truncation; otherwise round. */
5106 static tree
5109 {
5117 /* If we are not doing any checks, the output is an integral type, and
5118 the input is not a floating type, just do the conversion. This
5119 shortcut is required to avoid problems with packed array types
5120 and simplifies code in all cases anyway. */
5125 /* First convert the expression to its base type. This
5126 will never generate code, but makes the tests below much simpler.
5127 But don't do this if converting from an integer type to an unconstrained
5128 array type since then we need to get the bounds from the original
5129 (unpacked) type. */
5133 /* If overflow checks are requested, we need to be sure the result will
5134 fit in the output base type. But don't do this if the input
5135 is integer and the output floating-point. */
5138 {
5139 /* Ensure GNU_EXPR only gets evaluated once. */
5147 /* Convert the lower bounds to signed types, so we're sure we're
5148 comparing them properly. Likewise, convert the upper bounds
5149 to unsigned types. */
5163 /* Check each bound separately and only if the result bound
5164 is tighter than the bound on the input type. Note that all the
5165 types are base types, so the bounds must be constant. Also,
5166 the comparison is done in the base type of the input, which
5167 always has the proper signedness. First check for input
5168 integer (which means output integer), output float (which means
5169 both float), or mixed, in which case we always compare.
5170 Note that we have to do the comparison which would *fail* in the
5171 case of an error since if it's an FP comparison and one of the
5172 values is a NaN or Inf, the comparison will fail. */
5179 gnu_cond
5180 = invert_truthvalue
5183 gnu_out_lb)));
5191 gnu_cond
5193 invert_truthvalue
5195 gnu_input,
5197 gnu_out_ub))));
5201 CE_Overflow_Check_Failed);
5202 }
5204 /* Now convert to the result base type. If this is a non-truncating
5205 float-to-integer conversion, round. */
5208 {
5218 gnu_result
5220 }
5226 else
5229 /* Finally, do the range check if requested. Note that if the
5230 result type is a modular type, the range check is actually
5231 an overflow check. */
5239 }
5240 \f
5241 /* Return 1 if GNU_EXPR can be directly addressed. This is the case unless
5242 it is an expression involving computation or if it involves a bitfield
5243 reference. This returns the same as gnat_mark_addressable in most
5244 cases. */
5246 static bool
5248 {
5250 {
5255 /* All DECLs are addressable: if they are in a register, we can force
5256 them to memory. */
5282 {
5283 /* This is addressable if we can avoid a copy. */
5297 }
5301 }
5302 }
5303 \f
5304 /* Do the processing for the declaration of a GNAT_ENTITY, a type. If
5305 a separate Freeze node exists, delay the bulk of the processing. Otherwise
5306 make a GCC type for GNAT_ENTITY and set up the correspondance. */
5308 void
5310 {
5311 tree gnu_old
5313 tree gnu_new;
5315 /* If we are to delay elaboration of this type, just do any
5316 elaborations needed for expressions within the declaration and
5317 make a dummy type entry for this node and its Full_View (if
5318 any) in case something points to it. Don't do this if it
5319 has already been done (the only way that can happen is if
5320 the private completion is also delayed). */
5326 {
5330 {
5339 }
5342 }
5344 /* If we saved away a dummy type for this node it means that this
5345 made the type that corresponds to the full type of an incomplete
5346 type. Clear that type for now and then update the type in the
5347 pointers. */
5349 {
5352 {
5353 /* If this was a withed access type, this is not an error
5354 and merely indicates we've already elaborated the type
5355 already. */
5360 }
5363 }
5365 /* Now fully elaborate the type. */
5370 /* If we have an old type and we've made pointers to this type,
5371 update those pointers. */
5376 /* If this is a record type corresponding to a task or protected type
5377 that is a completion of an incomplete type, perform a similar update
5378 on the type. */
5379 /* ??? Including protected types here is a guess. */
5384 {
5385 tree gnu_task_old
5395 }
5396 }
5397 \f
5398 /* GNAT_ASSOC is the front of the Component_Associations of an N_Aggregate.
5399 GNU_TYPE is the GCC type of the corresponding record.
5401 Return a CONSTRUCTOR to build the record. */
5403 static tree
5405 {
5408 /* We test for GNU_FIELD being empty in the case where a variant
5409 was the last thing since we don't take things off GNAT_ASSOC in
5410 that case. We check GNAT_ASSOC in case we have a variant, but it
5411 has no fields. */
5415 {
5420 /* The expander is supposed to put a single component selector name
5421 in every record component association */
5425 /* Before assigning a value in an aggregate make sure range checks
5426 are done if required. Then convert to the type of the field. */
5432 /* Add the field and expression to the list. */
5434 }
5438 /* Verify every enty in GNU_LIST was used. */
5444 }
5446 /* Builds a possibly nested constructor for array aggregates. GNAT_EXPR
5447 is the first element of an array aggregate. It may itself be an
5448 aggregate (an array or record aggregate). GNU_ARRAY_TYPE is the gnu type
5449 corresponding to the array aggregate. GNAT_COMPONENT_TYPE is the type
5450 of the array component. It is needed for range checking. */
5452 static tree
5454 Entity_Id gnat_component_type)
5455 {
5458 tree gnu_expr;
5461 {
5462 /* If the expression is itself an array aggregate then first build the
5463 innermost constructor if it is part of our array (multi-dimensional
5464 case). */
5471 gnat_component_type);
5472 else
5473 {
5476 /* before assigning the element to the array make sure it is
5477 in range */
5480 }
5482 gnu_expr_list
5484 gnu_expr_list);
5487 }
5490 }
5491 \f
5492 /* Subroutine of assoc_to_constructor: VALUES is a list of field associations,
5493 some of which are from RECORD_TYPE. Return a CONSTRUCTOR consisting
5494 of the associations that are from RECORD_TYPE. If we see an internal
5495 record, make a recursive call to fill it in as well. */
5497 static tree
5499 {
5504 {
5507 /* _Parent is an internal field, but may have values in the aggregate,
5508 so check for values first. */
5510 {
5513 }
5516 {
5520 }
5521 else
5522 /* If we have a record subtype, the names will match, but not the
5523 actual FIELD_DECLs. */
5526 {
5529 }
5535 }
5538 }
5539 \f
5540 /* EXP is to be treated as an array or record. Handle the cases when it is
5541 an access object and perform the required dereferences. */
5543 static tree
5545 {
5546 /* If the type is a pointer, dereference it. */
5551 /* If we got a padded type, remove it too. */
5557 }
5558 \f
5559 /* Protect EXP from multiple evaluation. This may make a SAVE_EXPR. */
5561 tree
5563 {
5566 /* If this has no side effects, we don't need to do anything. */
5570 /* If it is a conversion, protect what's inside the conversion.
5571 Similarly, if we're indirectly referencing something, we only
5572 actually need to protect the address since the data itself can't
5573 change in these situations. */
5582 /* If EXP is a fat pointer or something that can be placed into a register,
5583 just make a SAVE_EXPR. */
5587 /* Otherwise, dereference, protect the address, and re-reference. */
5588 else
5589 return
5593 exp)));
5594 }
5595 \f
5596 /* This is equivalent to stabilize_reference in GCC's tree.c, but we know
5597 how to handle our new nodes and we take an extra argument that says
5598 whether to force evaluation of everything. */
5600 tree
5602 {
5605 tree result;
5608 {
5612 /* No action is needed in this case. */
5624 result
5633 force));
5639 force),
5647 force),
5649 force));
5657 force),
5664 force),
5666 force));
5669 /* If arg isn't a kind of lvalue we recognize, make no change.
5670 Caller should recognize the error for an invalid lvalue. */
5676 }
5680 /* TREE_THIS_VOLATILE and TREE_SIDE_EFFECTS attached to the initial
5681 expression may not be sustained across some paths, such as the way via
5682 build1 for INDIRECT_REF. We re-populate those flags here for the general
5683 case, which is consistent with the GCC version of this routine.
5685 Special care should be taken regarding TREE_SIDE_EFFECTS, because some
5686 paths introduce side effects where there was none initially (e.g. calls
5687 to save_expr), and we also want to keep track of that. */
5693 }
5695 /* Similar to stabilize_reference_1 in tree.c, but supports an extra
5696 arg to force a SAVE_EXPR for everything. */
5698 static tree
5700 {
5703 tree result;
5705 /* We cannot ignore const expressions because it might be a reference
5706 to a const array but whose index contains side-effects. But we can
5707 ignore things that are actual constant or that already have been
5708 handled by this function. */
5714 {
5722 /* If this is a COMPONENT_REF of a fat pointer, save the entire
5723 fat pointer. This may be more efficient, but will also allow
5724 us to more easily find the match for the PLACEHOLDER_EXPR. */
5729 force),
5733 else
5738 /* Constants need no processing. In fact, we should never reach
5739 here. */
5743 /* Recursively stabilize each operand. */
5747 force));
5751 /* Recursively stabilize each operand. */
5754 force));
5759 }
5766 }
5767 \f
5770 /* Convert Sloc into *LOCUS (a location_t). Return true if this Sloc
5771 corresponds to a source code location and false if it doesn't. In the
5772 latter case, we don't update *LOCUS. We also set the Gigi global variable
5773 REF_FILENAME to the reference file name as given by sinput (i.e no
5774 directory). */
5776 bool
5778 {
5779 /* If node not from source code, ignore. */
5783 /* Use the identifier table to make a hashed, permanent copy of the filename,
5784 since the name table gets reallocated after Gigi returns but before all
5785 the debugging information is output. The __gnat_to_canonical_file_spec
5786 call translates filenames from pragmas Source_Reference that contain host
5787 style syntax not understood by gdb. */
5788 locus->file
5789 = IDENTIFIER_POINTER
5790 (get_identifier
5791 (__gnat_to_canonical_file_spec
5796 ref_filename
5797 = IDENTIFIER_POINTER
5798 (get_identifier
5802 }
5804 /* Similar to annotate_with_locus, but start with the Sloc of GNAT_NODE and
5805 don't do anything if it doesn't correspond to a source location. */
5807 static void
5809 {
5810 location_t locus;
5816 }
5817 \f
5818 /* Post an error message. MSG is the error message, properly annotated.
5819 NODE is the node at which to post the error and the node to use for the
5820 "&" substitution. */
5822 void
5824 {
5825 String_Template temp;
5826 Fat_Pointer fp;
5832 }
5834 /* Similar, but NODE is the node at which to post the error and ENT
5835 is the node to use for the "&" substitution. */
5837 void
5839 {
5840 String_Template temp;
5841 Fat_Pointer fp;
5847 }
5849 /* Similar, but NODE is the node at which to post the error, ENT is the node
5850 to use for the "&" substitution, and N is the number to use for the ^. */
5852 void
5854 {
5855 String_Template temp;
5856 Fat_Pointer fp;
5864 }
5865 \f
5866 /* Similar to post_error_ne_num, but T is a GCC tree representing the
5867 number to write. If the tree represents a constant that fits within
5868 a host integer, the text inside curly brackets in MSG will be output
5869 (presumably including a '^'). Otherwise that text will not be output
5870 and the text inside square brackets will be output instead. */
5872 void
5874 {
5877 Fat_Pointer fp;
5885 #if HOST_BITS_PER_WIDE_INT > HOST_BITS_PER_INT
5886 &&
5887 compare_tree_int
5889 #endif
5890 )
5891 {
5894 }
5895 else
5899 {
5905 ;
5906 else
5908 }
5915 }
5917 /* Similar to post_error_ne_tree, except that NUM is a second
5918 integer to write in the message. */
5920 void
5922 Node_Id node,
5923 Entity_Id ent,
5924 tree t,
5926 {
5929 }
5931 /* Set the node for a second '&' in the error message. */
5933 void
5935 {
5937 }
5938 \f
5939 /* Initialize the table that maps GNAT codes to GCC codes for simple
5940 binary and unary operations. */
5942 void
5944 {
5970 }