| blob | 2acf8323849e8b10fdbc6f8293c6e4e09586d93a |
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. */
244 /* Now see if we have any elaboration procedures to deal with. */
246 {
248 tree gnu_stmts;
250 /* Mark everything we have as not visited. */
253 /* Set the current function to be the elaboration procedure and gimplify
254 what we have. */
258 /* We should have a BIND_EXPR, but it may or may not have any statements
259 in it. If it doesn't have any, we have nothing to do. */
264 /* If there are no statements, there is no elaboration code. */
267 else
268 {
269 /* Otherwise, compile the function. Note that we'll be gimplifying
270 it twice, but that's fine for the nodes we use. */
273 }
274 }
275 }
276 \f
277 /* Perform initializations for this module. */
279 void
281 {
282 /* Initialize ourselves. */
286 /* Enable GNAT stack checking method if needed */
294 }
295 \f
296 /* Subroutine of gnat_to_gnu to translate gnat_node, an N_Identifier,
297 to a GCC tree, which is returned. GNU_RESULT_TYPE_P is a pointer to
298 where we should place the result type. */
300 static tree
302 {
303 tree gnu_result_type;
304 tree gnu_result;
307 /* If the Etype of this node does not equal the Etype of the Entity,
308 something is wrong with the entity map, probably in generic
309 instantiation. However, this does not apply to types. Since we sometime
310 have strange Ekind's, just do this test for objects. Also, if the Etype of
311 the Entity is private, the Etype of the N_Identifier is allowed to be the
312 full type and also we consider a packed array type to be the same as the
313 original type. Similarly, a class-wide type is equivalent to a subtype of
314 itself. Finally, if the types are Itypes, one may be a copy of the other,
315 which is also legal. */
338 /* If this is a reference to a deferred constant whose partial view is an
339 unconstrained private type, the proper type is on the full view of the
340 constant, not on the full view of the type, which may be unconstrained.
342 This may be a reference to a type, for example in the prefix of the
343 attribute Position, generated for dispatching code (see Make_DT in
344 exp_disp,adb). In that case we need the type itself, not is parent,
345 in particular if it is a derived type */
350 {
354 }
355 else
356 {
357 /* Expand the type of this identitier first, in case it is an enumeral
358 literal, which only get made when the type is expanded. There is no
359 order-of-elaboration issue here. We want to use the Actual_Subtype if
360 it has already been elaborated, otherwise the Etype. Avoid using
361 Actual_Subtype for packed arrays to simplify things. */
369 else
373 }
377 /* If we are in an exception handler, force this variable into memory to
378 ensure optimization does not remove stores that appear redundant but are
379 actually needed in case an exception occurs.
381 ??? Note that we need not do this if the variable is declared within the
382 handler, only if it is referenced in the handler and declared in an
383 enclosing block, but we have no way of testing that right now.
385 ??? Also, for now all we can do is make it volatile. But we only
386 do this for SJLJ. */
391 /* Some objects (such as parameters passed by reference, globals of
392 variable size, and renamed objects) actually represent the address
393 of the object. In that case, we must do the dereference. Likewise,
394 deal with parameters to foreign convention subprograms. Call fold
395 here since GNU_RESULT may be a CONST_DECL. */
400 {
402 tree initial;
406 gnu_result
409 gnu_result));
411 /* If the object is constant, we try to do the dereference directly
412 through the DECL_INITIAL. This is actually required in order to get
413 correct aliasing information for renamed objects that are components
414 of non-aliased aggregates, because the type of the renamed object and
415 that of the aggregate don't alias.
417 Note that we expect the initial value to have been stabilized.
418 If it contains e.g. a variable reference, we certainly don't want
419 to re-evaluate the variable each time the renaming is used.
421 Stabilization is currently not performed at the global level but
422 create_var_decl avoids setting DECL_INITIAL if the value is not
423 constant then, and we get to the pointer dereference below.
425 ??? Couldn't the aliasing issue show up again in this case ?
426 There is no obvious reason why not. */
429 /* Strip possible conversion to reference type. */
431 == NOP_EXPR
439 else
444 }
446 /* The GNAT tree has the type of a function as the type of its result. Also
447 use the type of the result if the Etype is a subtype which is nominally
448 unconstrained. But remove any padding from the resulting type. */
451 {
456 }
458 /* We always want to return the underlying INTEGER_CST for an enumeration
459 literal to avoid the need to call fold in lots of places. But don't do
460 this is the parent will be taking the address of this object. */
462 {
476 }
480 }
481 \f
482 /* Subroutine of gnat_to_gnu to process gnat_node, an N_Pragma. Return
483 any statements we generate. */
485 static tree
487 {
488 Node_Id gnat_temp;
491 /* Check for (and ignore) unrecognized pragma and do nothing if we are just
492 annotating types. */
497 {
499 /* Do nothing at top level: all such variables are already viewable. */
506 {
515 }
521 {
534 }
541 }
544 }
545 /* Subroutine of gnat_to_gnu to translate gnat_node, an N_Attribute,
546 to a GCC tree, which is returned. GNU_RESULT_TYPE_P is a pointer to
547 where we should place the result type. ATTRIBUTE is the attribute ID. */
549 static tree
551 {
553 tree gnu_result_type;
554 tree gnu_expr;
559 /* If the input is a NULL_EXPR, make a new one. */
561 {
565 }
568 {
571 /* These are just conversions until since representation clauses for
572 enumerations are handled in the front end. */
573 {
580 }
585 /* These just add or subject the constant 1. Representation clauses for
586 enumerations are handled in the front-end. */
591 {
593 gnu_expr
594 = emit_check
596 gnu_expr,
597 attribute == Attr_Pred
601 }
603 gnu_result
612 /* Conversions don't change something's address but can cause us to miss
613 the COMPONENT_REF case below, so strip them off. */
617 /* If we are taking 'Address of an unconstrained object, this is the
618 pointer to the underlying array. */
621 /* ... fall through ... */
627 gnu_result
634 /* For 'Code_Address, find an inner ADDR_EXPR and mark it so that we
635 don't try to build a trampoline. */
637 {
646 }
650 {
651 tree gnu_obj_type;
656 /* If this is an unconstrained array, we know the object must have been
657 allocated with the template in front of the object. So compute the
658 template address.*/
660 gnu_ptr
662 (TYPE_OBJECT_RECORD_TYPE
664 gnu_ptr);
669 {
672 tree gnu_byte_offset
679 }
682 }
691 /* Remove NOPS from gnu_expr and conversions from gnu_prefix.
692 We only use GNU_EXPR to see if a COMPONENT_REF was involved. */
695 ;
701 /* Replace an unconstrained array type with the type of the underlying
702 array. We can't do this with a call to maybe_unconstrained_array
703 since we may have a TYPE_DECL. For 'Max_Size_In_Storage_Elements,
704 use the record type that will be used to allocate the object and its
705 template. */
707 {
711 }
713 /* If we're looking for the size of a field, return the field size.
714 Otherwise, if the prefix is an object, or if 'Object_Size or
715 'Max_Size_In_Storage_Elements has been specified, the result is the
716 GCC size of the type. Otherwise, the result is the RM_Size of the
717 type. */
723 {
724 /* If this is a padded type, the GCC size isn't relevant to the
725 programmer. Normally, what we want is the RM_Size, which was set
726 from the specified size, but if it was not set, we want the size
727 of the relevant field. Using the MAX of those two produces the
728 right result in all case. Don't use the size of the field if it's
729 a self-referential type, since that's never what's wanted. */
733 {
737 gnu_result
740 }
741 else
743 }
744 else
749 /* Deal with a self-referential size by returning the maximum size for a
750 type and by qualifying the size with the object for 'Size of an
751 object. */
753 {
756 gnu_expr);
757 else
759 }
761 /* If the type contains a template, subtract its size. */
769 /* Always perform division using unsigned arithmetic as the size cannot
770 be negative, but may be an overflowed positive value. This provides
771 correct results for sizes up to 512 MB.
773 ??? Size should be calculated in storage elements directly. */
794 else
804 {
811 else
812 gnu_result
813 = build_binary_op
815 build_binary_op
827 }
829 /* ... fall through ... */
832 {
837 /* Make sure any implicit dereference gets done. */
845 {
847 tree gnu_type_temp;
853 ;
856 }
863 gnu_result
866 gnu_result
868 else
869 /* 'Length or 'Range_Length. */
870 {
871 tree gnu_compute_type
875 gnu_result
876 = build_binary_op
878 build_binary_op
880 build_binary_op
883 TYPE_MAX_VALUE
886 TYPE_MIN_VALUE
890 }
892 /* If this has a PLACEHOLDER_EXPR, qualify it by the object we are
893 handling. Note that these attributes could not have been used on
894 an unconstrained array type. */
896 gnu_prefix);
898 }
905 {
906 HOST_WIDE_INT bitsize;
907 HOST_WIDE_INT bitpos;
908 tree gnu_offset;
909 tree gnu_field_bitpos;
910 tree gnu_field_offset;
911 tree gnu_inner;
919 /* We can have 'Bit on any object, but if it isn't a COMPONENT_REF,
920 the result is 0. Don't allow 'Bit on a bare component, though. */
924 {
927 }
929 else
938 {
946 {
947 gnu_field_bitpos
950 gnu_field_offset
953 }
954 }
956 {
959 }
960 else
961 {
964 }
967 {
982 bitsize_one_node);
988 }
990 /* If this has a PLACEHOLDER_EXPR, qualify it by the object
991 we are handling. */
994 }
998 {
1006 }
1034 /* Note this size cannot be self-referential. */
1041 /* This is just a zero cast to the pointer type for
1042 our prefix and dereferenced. */
1044 gnu_result
1047 integer_zero_node));
1052 {
1059 {
1064 ;
1065 }
1073 && (DECL_BY_COMPONENT_PTR_P
1077 }
1081 /* Say we have an unimplemented attribute. Then set the value to be
1082 returned to be a zero and hope that's something we can convert to the
1083 type of this attribute. */
1088 }
1090 /* If this is an attribute where the prefix was unused, force a use of it if
1091 it has a side-effect. But don't do it if the prefix is just an entity
1092 name. However, if an access check is needed, we must do it. See second
1093 example in AARM 11.6(5.e). */
1101 }
1102 \f
1103 /* Subroutine of gnat_to_gnu to translate gnat_node, an N_Case_Statement,
1104 to a GCC tree, which is returned. */
1106 static tree
1108 {
1109 tree gnu_result;
1110 tree gnu_expr;
1111 Node_Id gnat_when;
1116 /* The range of values in a case statement is determined by the rules in
1117 RM 5.4(7-9). In almost all cases, this range is represented by the Etype
1118 of the expression. One exception arises in the case of a simple name that
1119 is parenthesized. This still has the Etype of the name, but since it is
1120 not a name, para 7 does not apply, and we need to go to the base type.
1121 This is the only case where parenthesization affects the dynamic
1122 semantics (i.e. the range of possible values at runtime that is covered
1123 by the others alternative.
1125 Another exception is if the subtype of the expression is non-static. In
1126 that case, we also have to use the base type. */
1132 /* We build a SWITCH_EXPR that contains the code with interspersed
1133 CASE_LABEL_EXPRs for each label. */
1140 {
1141 Node_Id gnat_choice;
1143 /* First compile all the different case choices for the current WHEN
1144 alternative. */
1147 {
1151 {
1166 /* This represents either a subtype range or a static value of
1167 some kind; Ekind says which. If a static value, fall through
1168 to the next case. */
1170 {
1176 }
1178 /* ... fall through ... */
1190 }
1195 gnat_choice);
1196 }
1198 /* Push a binding level here in case variables are declared since we want
1199 them to be local to this set of statements instead of the block
1200 containing the Case statement. */
1204 }
1206 /* Now emit a definition of the label all the cases branched to. */
1214 }
1215 \f
1216 /* Subroutine of gnat_to_gnu to translate gnat_node, an N_Loop_Statement,
1217 to a GCC tree, which is returned. */
1219 static tree
1221 {
1222 /* ??? It would be nice to use "build" here, but there's no build5. */
1228 tree gnu_result;
1235 /* Save the end label of this LOOP_STMT in a stack so that the corresponding
1236 N_Exit_Statement can find it. */
1240 /* Set the condition that under which the loop should continue.
1241 For "LOOP .... END LOOP;" the condition is always true. */
1243 ;
1244 /* The case "WHILE condition LOOP ..... END LOOP;" */
1248 else
1249 {
1250 /* We have an iteration scheme. */
1265 /* We know the loop variable will not overflow if GNU_LAST is a constant
1266 and is not equal to GNU_LIMIT. If it might overflow, we have to move
1267 the limit test to the end of the loop. In that case, we have to test
1268 for an empty loop outside the loop. */
1272 {
1273 gnu_cond_expr
1279 }
1281 /* Open a new nesting level that will surround the loop to declare the
1282 loop index variable. */
1286 /* Declare the loop index and set it to its initial value. */
1291 /* The loop variable might be a padded type, so use `convert' to get a
1292 reference to the inner variable if so. */
1295 /* Set either the top or bottom exit condition as appropriate depending
1296 on whether or not we know an overflow cannot occur. */
1301 else
1310 gnu_loop_var,
1312 integer_one_node));
1314 gnat_iter_scheme);
1315 }
1317 /* If the loop was named, have the name point to this loop. In this case,
1318 the association is not a ..._DECL node, but the end label from this
1319 LOOP_STMT. */
1324 /* Make the loop body into its own block, so any allocated storage will be
1325 released every iteration. This is needed for stack allocation. */
1329 /* If we declared a variable, then we are in a statement group for that
1330 declaration. Add the LOOP_STMT to it and make that the "loop". */
1332 {
1336 }
1338 /* If we have an outer COND_EXPR, that's our result and this loop is its
1339 "true" statement. Otherwise, the result is the LOOP_STMT. */
1341 {
1345 }
1346 else
1352 }
1353 \f
1354 /* Subroutine of gnat_to_gnu to process gnat_node, an N_Subprogram_Body. We
1355 don't return anything. */
1357 static void
1359 {
1360 /* Save debug output mode in case it is reset. */
1363 /* Definining identifier of a parameter to the subprogram. */
1364 Entity_Id gnat_param;
1365 /* The defining identifier for the subprogram body. Note that if a
1366 specification has appeared before for this body, then the identifier
1367 occurring in that specification will also be a defining identifier and all
1368 the calls to this subprogram will point to that specification. */
1369 Entity_Id gnat_subprog_id
1372 /* The FUNCTION_DECL node corresponding to the subprogram spec. */
1373 tree gnu_subprog_decl;
1374 /* The FUNCTION_TYPE node corresponding to the subprogram spec. */
1375 tree gnu_subprog_type;
1376 tree gnu_cico_list;
1377 tree gnu_result;
1379 /* If this is a generic object or if it has been eliminated,
1380 ignore it. */
1386 /* If debug information is suppressed for the subprogram, turn debug
1387 mode off for the duration of processing. */
1389 {
1392 }
1394 /* If this subprogram acts as its own spec, define it. Otherwise, just get
1395 the already-elaborated tree node. However, if this subprogram had its
1396 elaboration deferred, we will already have made a tree node for it. So
1397 treat it as not being defined in that case. Such a subprogram cannot
1398 have an address clause or a freeze node, so this test is safe, though it
1399 does disable some otherwise-useful error checking. */
1400 gnu_subprog_decl
1407 /* Set the line number in the decl to correspond to that of the body so that
1408 the line number notes are written
1409 correctly. */
1415 /* If there are OUT parameters, we need to ensure that the return statement
1416 properly copies them out. We do this by making a new block and converting
1417 any inner return into a goto to a label at the end of the block. */
1421 /* Get a tree corresponding to the code for the subprogram. */
1425 /* See if there are any parameters for which we don't yet have GCC entities.
1426 These must be for OUT parameters for which we will be making VAR_DECL
1427 nodes here. Fill them in to TYPE_CI_CO_LIST, which must contain the empty
1428 entry as well. We can match up the entries because TYPE_CI_CO_LIST is in
1429 the order of the parameters. */
1434 {
1435 /* Skip any entries that have been already filled in; they must
1436 correspond to IN OUT parameters. */
1439 ;
1441 /* Do any needed references for padded types. */
1445 }
1449 /* Generate the code of the subprogram itself. A return statement will be
1450 present and any OUT parameters will be handled there. */
1455 /* If we made a special return label, we need to make a block that contains
1456 the definition of that label and the copying to the return value. That
1457 block first contains the function, then the label and copy statement. */
1459 {
1460 tree gnu_retval;
1471 else
1473 gnu_cico_list);
1478 add_stmt_with_node
1482 gnat_node);
1485 }
1489 /* Initialize the information node for the function and set the
1490 end location. */
1492 Sloc_to_locus
1500 /* Disconnect the trees for parameters that we made variables for from the
1501 GNAT entities since these are unusable after we end the function. */
1511 }
1512 \f
1513 /* Subroutine of gnat_to_gnu to translate gnat_node, either an N_Function_Call
1514 or an N_Procedure_Call_Statement, to a GCC tree, which is returned.
1515 GNU_RESULT_TYPE_P is a pointer to where we should place the result type.
1516 If GNU_TARGET is non-null, this must be a function call and the result
1517 of the call is to be placed into that object. */
1519 static tree
1521 {
1522 tree gnu_result;
1523 /* The GCC node corresponding to the GNAT subprogram name. This can either
1524 be a FUNCTION_DECL node if we are dealing with a standard subprogram call,
1525 or an indirect reference expression (an INDIRECT_REF node) pointing to a
1526 subprogram. */
1528 /* The FUNCTION_TYPE node giving the GCC type of the subprogram. */
1531 gnu_subprog_node);
1532 Entity_Id gnat_formal;
1533 Node_Id gnat_actual;
1538 tree gnu_subprog_call;
1541 {
1548 }
1552 /* If we are calling a stubbed function, make this into a raise of
1553 Program_Error. Elaborate all our args first. */
1556 {
1563 {
1567 }
1568 else
1570 }
1572 /* If we are calling by supplying a pointer to a target, set up that
1573 pointer as the first argument. Use GNU_TARGET if one was passed;
1574 otherwise, make a target by building a variable of the maximum size
1575 of the type. */
1577 {
1578 tree gnu_real_ret_type
1582 {
1583 tree gnu_obj_type
1591 }
1593 gnu_actual_list
1597 gnu_target,
1599 NULL_TREE);
1601 }
1603 /* The only way we can be making a call via an access type is if Name is an
1604 explicit dereference. In that case, get the list of formal args from the
1605 type the access type is pointing to. Otherwise, get the formals from
1606 entity being called. */
1610 /* Assume here that this must be 'Elab_Body or 'Elab_Spec. */
1612 else
1615 /* Create the list of the actual parameters as GCC expects it, namely a chain
1616 of TREE_LIST nodes in which the TREE_VALUE field of each node is a
1617 parameter-expression and the TREE_PURPOSE field is null. Skip OUT
1618 parameters not passed by reference and don't need to be copied in. */
1623 {
1624 tree gnu_formal
1627 /* We treat a conversion between aggregate types as if it is an
1628 unchecked conversion. */
1629 bool unchecked_convert_p
1633 Node_Id gnat_name = (unchecked_convert_p
1637 tree gnu_actual;
1638 tree gnu_formal_type;
1640 /* If it's possible we may need to use this expression twice, make sure
1641 than any side-effects are handled via SAVE_EXPRs. Likewise if we need
1642 to force side-effects before the call.
1644 ??? This is more conservative than we need since we don't need to do
1645 this for pass-by-ref with no conversion. If we are passing a
1646 non-addressable Out or In Out parameter by reference, pass the address
1647 of a copy and set up to copy back out after the call. */
1649 {
1652 && gnu_formal
1657 {
1659 tree gnu_temp;
1661 /* Remove any unpadding on the actual and make a copy. But if
1662 the actual is a justified modular type, first convert
1663 to it. */
1667 && (TYPE_IS_PADDING_P
1676 /* Since we're going to take the address of the SAVE_EXPR, we
1677 don't want it to be marked as unchanging. So set
1678 TREE_ADDRESSABLE. */
1681 {
1684 }
1686 /* Set up to move the copy back to the original. */
1691 }
1692 }
1694 /* If this was a procedure call, we may not have removed any padding.
1695 So do it here for the part we will use as an input, if any. */
1701 gnu_actual);
1703 /* Unless this is an In parameter, we must remove any LJM building
1704 from GNU_NAME. */
1710 gnu_name);
1713 && !unchecked_convert_p
1717 /* Do any needed conversions. We need only check for unchecked
1718 conversion since normal conversions will be handled by just
1719 converting to the formal type. */
1721 {
1722 gnu_actual
1724 gnu_actual,
1729 /* One we've done the unchecked conversion, we still must ensure that
1730 the object is in range of the formal's type. */
1735 }
1737 /* We may have suppressed a conversion to the Etype of the actual since
1738 the parent is a procedure call. So add the conversion here. */
1740 gnu_actual);
1742 /* If we have not saved a GCC object for the formal, it means it is an
1743 OUT parameter not passed by reference and that does not need to be
1744 copied in. Otherwise, look at the PARM_DECL to see if it is passed by
1745 reference. */
1748 {
1750 {
1753 /* If we have a padded type, be sure we've removed padding. */
1758 gnu_actual);
1760 /* If we have the constructed subtype of an aliased object
1761 with an unconstrained nominal subtype, the type of the
1762 actual includes the template, although it is formally
1763 constrained. So we need to convert it back to the real
1764 constructed subtype to retrieve the constrained part
1765 and takes its address. */
1772 gnu_actual);
1773 }
1775 /* Otherwise, if we have a non-addressable COMPONENT_REF of a
1776 variable-size type see if it's doing a unpadding operation. If
1777 so, remove that operation since we have no way of allocating the
1778 required temporary. */
1788 /* The symmetry of the paths to the type of an entity is broken here
1789 since arguments don't know that they will be passed by ref. */
1792 }
1795 {
1802 {
1805 }
1807 /* Take the address of the object and convert to the proper pointer
1808 type. We'd like to actually compute the address of the beginning
1809 of the array using an ADDR_EXPR of an ARRAY_REF, but there's a
1810 possibility that the ARRAY_REF might return a constant and we'd be
1811 getting the wrong address. Neither approach is exactly correct,
1812 but this is the most likely to work in all cases. */
1815 gnu_actual));
1816 }
1819 {
1820 /* If arg is 'Null_Parameter, pass zero descriptor. */
1825 integer_zero_node);
1826 else
1829 gnat_formal));
1830 }
1831 else
1832 {
1841 /* If this is 'Null_Parameter, pass a zero even though we are
1842 dereferencing it. */
1847 BITS_PER_WORD))
1848 gnu_actual
1853 integer_zero_node),
1855 else
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)));
2090 /* Generate code for each statement in the block. */
2098 /* Now generate code for the two exception models, if either is relevant for
2099 this block. */
2101 {
2103 tree gnu_handler;
2105 /* Make a binding level for the exception handling declarations and code
2106 and set up gnu_except_ptr_stack for the handlers to use. */
2112 NULL_TREE,
2117 /* Generate code for each handler. The N_Exception_Handler case does the
2118 real work and returns a COND_EXPR for each handler, which we chain
2119 together here. */
2122 {
2125 /* If this is the first one, set it as the outer one. Otherwise,
2126 point the "else" part of the previous handler to us. Then point
2127 to our "else" part. */
2130 else
2134 }
2136 /* If none of the exception handlers did anything, re-raise but do not
2137 defer abortion. */
2144 else
2147 /* End the binding level dedicated to the exception handlers and get the
2148 whole statement group. */
2153 /* If the setjmp returns 1, we restore our incoming longjmp value and
2154 then check the handlers. */
2157 gnu_jmpsave_decl),
2158 gnat_node);
2162 /* This block is now "if (setjmp) ... <handlers> else <block>". */
2164 (build_call_1_expr
2167 gnu_jmpbuf_decl))),
2169 }
2171 {
2172 tree gnu_handlers;
2174 /* First make a block containing the handlers. */
2182 /* Now make the TRY_CATCH_EXPR for the block. */
2185 }
2186 else
2189 /* Now close our outer block, if we had to make one. */
2191 {
2195 }
2198 }
2199 \f
2200 /* Subroutine of gnat_to_gnu to translate gnat_node, an N_Exception_Handler,
2201 to a GCC tree, which is returned. This is the variant for Setjmp_Longjmp
2202 exception handling. */
2204 static tree
2206 {
2207 /* Unless this is "Others" or the special "Non-Ada" exception for Ada, make
2208 an "if" statement to select the proper exceptions. For "Others", exclude
2209 exceptions where Handled_By_Others is nonzero unless the All_Others flag
2210 is set. For "Non-ada", accept an exception if "Lang" is 'V'. */
2213 Node_Id gnat_temp;
2217 {
2218 tree this_choice;
2221 {
2224 else
2225 this_choice
2226 = build_binary_op
2228 convert
2230 build_component_ref
2231 (build_unary_op
2236 integer_zero_node);
2237 }
2241 {
2243 tree gnu_expr;
2245 /* Exception may be a renaming. Recover original exception which is
2246 the one elaborated and registered. */
2252 this_choice
2253 = build_binary_op
2258 /* If this is the distinguished exception "Non_Ada_Error" (and we are
2259 in VMS mode), also allow a non-Ada exception (a VMS condition) t
2260 match. */
2262 {
2263 tree gnu_comp
2264 = build_component_ref
2269 this_choice
2270 = build_binary_op
2274 this_choice);
2275 }
2276 }
2277 else
2282 }
2285 }
2286 \f
2287 /* Subroutine of gnat_to_gnu to translate gnat_node, an N_Exception_Handler,
2288 to a GCC tree, which is returned. This is the variant for ZCX. */
2290 static tree
2292 {
2294 tree gnu_expr;
2295 tree gnu_etype;
2296 tree gnu_current_exc_ptr;
2297 tree gnu_incoming_exc_ptr;
2298 Node_Id gnat_temp;
2300 /* We build a TREE_LIST of nodes representing what exception types this
2301 handler can catch, with special cases for others and all others cases.
2303 Each exception type is actually identified by a pointer to the exception
2304 id, or to a dummy object for "others" and "all others".
2306 Care should be taken to ensure that the control flow impact of "others"
2307 and "all others" is known to GCC. lang_eh_type_covers is doing the trick
2308 currently. */
2311 {
2313 {
2314 tree gnu_expr
2317 gnu_etype
2319 }
2322 {
2325 /* Exception may be a renaming. Recover original exception which is
2326 the one elaborated and registered. */
2333 /* The Non_Ada_Error case for VMS exceptions is handled
2334 by the personality routine. */
2335 }
2336 else
2339 /* The GCC interface expects NULL to be passed for catch all handlers, so
2340 it would be quite tempting to set gnu_etypes_list to NULL if gnu_etype
2341 is integer_zero_node. It would not work, however, because GCC's
2342 notion of "catch all" is stronger than our notion of "others". Until
2343 we correctly use the cleanup interface as well, doing that would
2344 prevent the "all others" handlers from beeing seen, because nothing
2345 can be caught beyond a catch all from GCC's point of view. */
2347 }
2352 /* Expand a call to the begin_handler hook at the beginning of the handler,
2353 and arrange for a call to the end_handler hook to occur on every possible
2354 exit path.
2356 The hooks expect a pointer to the low level occurrence. This is required
2357 for our stack management scheme because a raise inside the handler pushes
2358 a new occurrence on top of the stack, which means that this top does not
2359 necessarily match the occurrence this handler was dealing with.
2361 The EXC_PTR_EXPR object references the exception occurrence being
2362 propagated. Upon handler entry, this is the exception for which the
2363 handler is triggered. This might not be the case upon handler exit,
2364 however, as we might have a new occurrence propagated by the handler's
2365 body, and the end_handler hook called as a cleanup in this context.
2367 We use a local variable to retrieve the incoming value at handler entry
2368 time, and reuse it to feed the end_handler hook's argument at exit. */
2373 gnat_node);
2376 gnu_incoming_exc_ptr),
2377 gnat_node);
2384 }
2385 \f
2386 /* Subroutine of gnat_to_gnu to generate code for an N_Compilation unit. */
2388 static void
2390 {
2391 /* Make the decl for the elaboration procedure. */
2396 tree gnu_elab_proc_decl
2397 = create_subprog_decl
2401 gnat_unit_entity);
2411 /* For a body, first process the spec if there is one. */
2420 {
2427 }
2433 /* Process any pragmas and actions following the unit. */
2437 /* Save away what we've made so far and record this potential elaboration
2438 procedure. */
2448 /* Generate elaboration code for this unit, if necessary, and say whether
2449 we did or not. */
2451 }
2452 \f
2453 /* This function is the driver of the GNAT to GCC tree transformation
2454 process. It is the entry point of the tree transformer. GNAT_NODE is the
2455 root of some GNAT tree. Return the root of the corresponding GCC tree.
2456 If this is an expression, return the GCC equivalent of the expression. If
2457 it is a statement, return the statement. In the case when called for a
2458 statement, it may also add statements to the current statement group, in
2459 which case anything it returns is to be interpreted as occuring after
2460 anything `it already added. */
2462 tree
2464 {
2468 tree gnu_expr;
2470 Node_Id gnat_temp;
2472 /* Save node number for error message and set location information. */
2480 /* If this node is a non-static subexpression and we are only
2481 annotating types, make this into a NULL_EXPR. */
2489 /* If this is a Statement and we are at top level, it must be part of
2490 the elaboration procedure, so mark us as being in that procedure
2491 and push our context. */
2503 {
2508 }
2511 {
2512 /********************************/
2513 /* Chapter 2: Lexical Elements: */
2514 /********************************/
2524 {
2525 tree gnu_type;
2527 /* Get the type of the result, looking inside any padding and
2528 justified modular types. Then get the value in that type. */
2537 /* If the result overflows (meaning it doesn't fit in its base type),
2538 abort. We would like to check that the value is within the range
2539 of the subtype, but that causes problems with subtypes whose usage
2540 will raise Constraint_Error and with biased representation, so
2541 we don't. */
2543 }
2547 /* If a Entity is present, it means that this was one of the
2548 literals in a user-defined character type. In that case,
2549 just return the value in the CONST_DECL. Otherwise, use the
2550 character code. In that case, the base type should be an
2551 INTEGER_TYPE, but we won't bother checking for that. */
2555 else
2556 gnu_result
2557 = force_fit_type
2563 /* If this is of a fixed-point type, the value we want is the
2564 value of the corresponding integer. */
2566 {
2569 gnu_result_type);
2571 }
2573 /* We should never see a Vax_Float type literal, since the front end
2574 is supposed to transform these using appropriate conversions */
2578 else
2579 {
2584 /* If the real value is zero, so is the result. Otherwise,
2585 convert it to a machine number if it isn't already. That
2586 forces BASE to 0 or 2 and simplifies the rest of our logic. */
2589 else
2590 {
2592 ur_realval
2596 gnu_result
2599 /* If we have a base of zero, divide by the denominator.
2600 Otherwise, the base must be 2 and we scale the value, which
2601 we know can fit in the mantissa of the type (hence the use
2602 of that type above). */
2604 gnu_result
2607 gnu_result,
2609 gnu_result_type));
2610 else
2611 {
2612 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 {
2845 gnu_expr
2846 = emit_index_check
2853 }
2854 }
2860 {
2861 tree gnu_type;
2867 /* Do any implicit dereferences of the prefix and do any needed
2868 range check. */
2873 {
2874 /* Get the bounds of the slice. */
2875 tree gnu_index_type
2881 /* Check to see that the minimum slice value is in range */
2882 gnu_expr_l
2883 = emit_index_check
2888 /* Check to see that the maximum slice value is in range */
2889 gnu_expr_h
2890 = emit_index_check
2895 /* Derive a good type to convert everything too */
2898 /* Build a compound expression that does the range checks */
2899 gnu_expr
2904 /* Build a conditional expression that returns the range checks
2905 expression if the slice range is not null (max >= min) or
2906 returns the min if the slice range is null */
2907 gnu_expr
2911 gnu_max_expr),
2913 gnu_min_expr)),
2915 }
2916 else
2921 }
2925 {
2929 tree gnu_field;
2933 {
2938 }
2942 /* For discriminant references in tagged types always substitute the
2943 corresponding discriminant as the actual selected component. */
2949 /* For discriminant references of untagged types always substitute the
2950 corresponding stored discriminant. */
2955 /* Handle extracting the real or imaginary part of a complex.
2956 The real part is the first field and the imaginary the last. */
2962 else
2963 {
2966 /* If there are discriminants, the prefix might be
2967 evaluated more than once, which is a problem if it has
2968 side-effects. */
2975 gnu_result
2979 }
2983 }
2987 {
2988 /* The attribute designator (like an enumeration value). */
2991 /* The Elab_Spec and Elab_Body attributes are special in that
2992 Prefix is a unit, not an object with a GCC equivalent. Similarly
2993 for Elaborated, since that variable isn't otherwise known. */
2997 attribute == Attr_Elab_Body
3000 gnat_node));
3003 }
3007 /* Like 'Access as far as we are concerned. */
3015 {
3016 tree gnu_aggr_type;
3018 /* ??? It is wrong to evaluate the type now, but there doesn't
3019 seem to be any other practical way of doing it. */
3021 gnu_aggr_type = gnu_result_type
3026 gnu_aggr_type
3033 gnu_result
3035 gnu_aggr_type);
3037 {
3038 /* The first element is the discrimant, which we ignore. The
3039 next is the field we're building. Convert the expression
3040 to the type of the field and then to the union type. */
3041 Node_Id gnat_assoc
3044 tree gnu_field_type
3049 }
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
3509 /* If we are dealing with a "return;" from an Ada procedure with
3510 parameters passed by copy in copy out, we need to return a record
3511 containing the final values of these parameters. If the list
3512 contains only one entry, return just that entry.
3514 For a full description of the copy in copy out parameter mechanism,
3515 see the part of the gnat_to_gnu_entity routine dealing with the
3516 translation of subprograms.
3518 But if we have a return label defined, convert this into
3519 a branch to that label. */
3522 {
3526 }
3529 {
3532 else
3533 gnu_ret_val
3536 }
3538 /* If the Ada subprogram is a function, we just need to return the
3539 expression. If the subprogram returns an unconstrained
3540 array, we have to allocate a new version of the result and
3541 return it. If we return by reference, return a pointer. */
3544 {
3545 /* If the current function returns by target pointer and we
3546 are doing a call, pass that target to the call. */
3552 else
3553 {
3556 /* Do not remove the padding from GNU_RET_VAL if the inner
3557 type is self-referential since we want to allocate the fixed
3558 size in that case. */
3562 && (TYPE_IS_PADDING_P
3564 && (CONTAINS_PLACEHOLDER_P
3570 gnu_ret_val
3574 {
3577 /* We have two cases: either the function returns with
3578 depressed stack or not. If not, we allocate on the
3579 secondary stack. If so, we allocate in the stack frame.
3580 if no copy is needed, the front end will set By_Ref,
3581 which we handle in the case above. */
3583 gnu_ret_val
3585 gnu_ret_val,
3588 else
3589 gnu_ret_val
3591 gnu_ret_val,
3595 gnat_node);
3596 }
3597 }
3602 {
3605 }
3606 }
3610 }
3618 /****************************/
3619 /* Chapter 6: Subprograms: */
3620 /****************************/
3623 /* Unless there is a freeze node, declare the subprogram. We consider
3624 this a "definition" even though we're not generating code for
3625 the subprogram because we will be making the corresponding GCC
3626 node here. */
3635 /* This subprogram doesn't exist for code generation purposes, but we
3636 have to elaborate the types of any parameters, unless they are
3637 imported types (nothing to generate in this case). */
3650 /* For a child unit identifier go up a level to get the
3651 specificaton. We get this when we try to find the spec of
3652 a child unit package that is the compilation unit being compiled. */
3666 /*************************/
3667 /* Chapter 7: Packages: */
3668 /*************************/
3684 /* If this is the body of a generic package - do nothing */
3686 {
3689 }
3700 /*********************************/
3701 /* Chapter 8: Visibility Rules: */
3702 /*********************************/
3706 /* Nothing to do here - but these may appear in list of declarations */
3710 /***********************/
3711 /* Chapter 9: Tasks: */
3712 /***********************/
3723 /***********************************************************/
3724 /* Chapter 10: Program Structure and Compilation Issues: */
3725 /***********************************************************/
3729 /* This is not called for the main unit, which is handled in function
3730 gigi above. */
3742 /* Simply process whatever unit is being inserted. */
3750 /***************************/
3751 /* Chapter 11: Exceptions: */
3752 /***************************/
3755 /* If there is an At_End procedure attached to this node, and the EH
3756 mechanism is SJLJ, we must have at least a corresponding At_End
3757 handler, unless the No_Exception_Handlers restriction is set. */
3772 else
3777 /*******************************/
3778 /* Chapter 12: Generic Units: */
3779 /*******************************/
3789 /* These nodes can appear on a declaration list but there is nothing to
3790 to be done with them. */
3794 /***************************************************/
3795 /* Chapter 13: Representation Clauses and */
3796 /* Implementation-Dependent Features: */
3797 /***************************************************/
3803 /* The only one we need deal with is for 'Address. For the others, SEM
3804 puts the information elsewhere. We need only deal with 'Address
3805 if the object has a Freeze_Node (which it never will currently). */
3810 /* Get the value to use as the address and save it as the
3811 equivalent for GNAT_TEMP. When the object is frozen,
3812 gnat_to_gnu_entity will do the right thing. */
3820 /* We do nothing with these. SEM puts the information elsewhere. */
3826 {
3832 /* First process inputs, then outputs, then clobbers. */
3835 {
3840 gnu_input_list
3843 }
3847 {
3852 gnu_output_list
3855 }
3859 gnu_clobber_list
3862 gnu_clobber_list);
3870 }
3871 else
3876 /***************************************************/
3877 /* Added Nodes */
3878 /***************************************************/
3896 {
3898 tree gnu_obj_type;
3899 tree gnu_obj_size;
3902 /* If this is a thin pointer, we must dereference it to create
3903 a fat pointer, then go back below to a thin pointer. The
3904 reason for this is that we need a fat pointer someplace in
3905 order to properly compute the size. */
3909 gnu_ptr));
3911 /* If this is an unconstrained array, we know the object must
3912 have been allocated with the template in front of the object.
3913 So pass the template address, but get the total size. Do this
3914 by converting to a thin pointer. */
3916 gnu_ptr
3918 (TYPE_OBJECT_RECORD_TYPE
3920 gnu_ptr);
3928 {
3931 tree gnu_byte_offset
3938 }
3943 gnat_node);
3944 }
3951 {
3954 }
3959 /* If the type is VOID, this is a statement, so we need to
3960 generate the code for the call. Handle a Condition, if there
3961 is one. */
3963 {
3970 }
3971 else
3976 /* If the result is a pointer type, see if we are either converting
3977 from a non-pointer or from a pointer to a type with a different
3978 alias set and warn if so. If the result defined in the same unit as
3979 this unchecked convertion, we can allow this because we can know to
3980 make that type have alias set 0. */
3981 {
3992 {
3993 post_error_ne
3996 post_error
3998 gnat_node);
3999 post_error_ne
4002 }
4003 }
4016 }
4018 /* If we pushed our level as part of processing the elaboration routine,
4019 pop it back now. */
4021 {
4026 }
4028 /* Set the location information into the result. If we're supposed to
4029 return something of void_type, it means we have something we're
4030 elaborating for effect, so just return. */
4037 /* If the result is a constant that overflows, raise constraint error. */
4040 {
4043 gnu_result
4046 }
4048 /* If our result has side-effects and is of an unconstrained type,
4049 make a SAVE_EXPR so that we can be sure it will only be referenced
4050 once. Note we must do this before any conversions. */
4056 /* Now convert the result to the proper type. If the type is void or if
4057 we have no result, return error_mark_node to show we have no result.
4058 If the type of the result is correct or if we have a label (which doesn't
4059 have any well-defined type), return our result. Also don't do the
4060 conversion if the "desired" type involves a PLACEHOLDER_EXPR in its size
4061 since those are the cases where the front end may have the type wrong due
4062 to "instantiating" the unconstrained record with discriminant values
4063 or if this is a FIELD_DECL. If this is the Name of an assignment
4064 statement or a parameter of a procedure call, return what we have since
4065 the RHS has to be converted to our type there in that case, unless
4066 GNU_RESULT_TYPE has a simpler size. Similarly, if the two types are
4067 record types with the same name, the expression type has integral mode,
4068 and GNU_RESULT_TYPE BLKmode, don't convert. This will be the case when
4069 we are converting from a packable type to its actual type and we need
4070 those conversions to be NOPs in order for assignments into these types to
4071 work properly if the inner object is a bitfield and hence can't have
4072 its address taken. Finally, don't convert integral types that are the
4073 operand of an unchecked conversion since we need to ignore those
4074 conversions (for 'Valid). Otherwise, convert the result to the proper
4075 type. */
4095 && (CONTAINS_PLACEHOLDER_P
4099 {
4100 /* In this case remove padding only if the inner object is of
4101 self-referential size: in that case it must be an object of
4102 unconstrained type with a default discriminant. In other cases,
4103 we want to avoid copying too much data. */
4110 gnu_result);
4111 }
4127 {
4128 /* Remove any padding record, but do nothing more in this case. */
4132 gnu_result);
4133 }
4141 /* We don't need any NOP_EXPR or NON_LVALUE_EXPR on GNU_RESULT. */
4148 }
4149 \f
4150 /* Record the current code position in GNAT_NODE. */
4152 static void
4154 {
4159 }
4161 /* Insert the code for GNAT_NODE at the position saved for that node. */
4163 static void
4165 {
4168 }
4169 \f
4170 /* Start a new statement group chained to the previous group. */
4172 static void
4174 {
4177 /* First see if we can get one from the free list. */
4180 else
4186 }
4188 /* Add GNU_STMT to the current statement group. */
4190 void
4192 {
4195 /* If we're at top level, show everything in here is in use in case
4196 any of it is shared by a subprogram. */
4200 }
4202 /* Similar, but set the location of GNU_STMT to that of GNAT_NODE. */
4204 void
4206 {
4210 }
4212 /* Add a declaration statement for GNU_DECL to the current statement group.
4213 Get SLOC from Entity_Id. */
4215 void
4217 {
4218 tree gnu_stmt;
4220 /* If this is a variable that Gigi is to ignore, we may have been given
4221 an ERROR_MARK. So test for it. We also might have been given a
4222 reference for a renaming. So only do something for a decl. Also
4223 ignore a TYPE_DECL for an UNCONSTRAINED_ARRAY_TYPE. */
4229 /* If we are global, we don't want to actually output the DECL_EXPR for
4230 this decl since we already have evaluated the expressions in the
4231 sizes and positions as globals and doing it again would be wrong.
4232 But we do have to mark everything as used. */
4236 else
4237 {
4241 {
4245 }
4246 }
4248 /* If this is a DECL_EXPR for a variable with DECL_INITIAl set,
4249 there are two cases we need to handle here. */
4251 {
4255 /* If this is a DECL_EXPR for a variable with DECL_INITIAL set
4256 and decl has a padded type, convert it to the unpadded type so the
4257 assignment is done properly. */
4260 gnu_lhs
4263 /* Otherwise, if this is going into memory and the initializer isn't
4264 valid for the assembler and loader. Gimplification could do this,
4265 but would be run too late if -fno-unit-at-a-time. */
4272 {
4273 tree gnu_assign_stmt
4282 }
4283 }
4284 }
4286 /* Utility function to mark nodes with TREE_VISITED. Called from walk_tree.
4287 We use this to indicate all variable sizes and positions in global types
4288 may not be shared by any subprogram. */
4290 static tree
4292 {
4296 /* Don't mark a dummy type as visited because we want to mark its sizes
4297 and fields once it's filled in. */
4302 }
4304 /* Likewise, but to mark as unvisited. */
4306 static tree
4309 {
4313 }
4315 /* Add GNU_CLEANUP, a cleanup action, to the current code group. */
4317 static void
4319 {
4321 }
4323 /* Set the BLOCK node corresponding to the current code group to GNU_BLOCK. */
4325 void
4327 {
4330 }
4332 /* Return code corresponding to the current code group. It is normally
4333 a STATEMENT_LIST, but may also be a BIND_EXPR or TRY_FINALLY_EXPR if
4334 BLOCK or cleanups were set. */
4336 static tree
4338 {
4342 /* If this is a null list, allocate a new STATEMENT_LIST. Then, if there
4343 are cleanups, make a TRY_FINALLY_EXPR. Last, if there is a BLOCK,
4344 make a BIND_EXPR. Note that we nest in that because the cleanup may
4345 reference variables in the block. */
4357 /* Remove this group from the stack and add it to the free list. */
4363 }
4365 /* Add a list of statements from GNAT_LIST, a possibly-empty list of
4366 statements.*/
4368 static void
4370 {
4371 Node_Id gnat_node;
4377 }
4379 /* Build a tree from GNAT_LIST, a possibly-empty list of statements.
4380 If BINDING_P is true, push and pop a binding level around the list. */
4382 static tree
4384 {
4394 }
4395 \f
4396 /* Push and pop routines for stacks. We keep a free list around so we
4397 don't waste tree nodes. */
4399 static void
4401 {
4405 {
4410 }
4411 else
4415 }
4417 static void
4419 {
4425 }
4426 \f
4427 /* GNU_STMT is a statement. We generate code for that statement. */
4429 void
4431 {
4432 #if 0
4434 #endif
4437 {
4438 #if 0
4440 /* First write a volatile ASM_INPUT to prevent anything from being
4441 moved. */
4447 modifier);
4450 #endif
4454 }
4455 }
4456 \f
4457 /* Generate GIMPLE in place for the expression at *EXPR_P. */
4459 int
4461 {
4468 {
4470 /* If this is for a scalar, just make a VAR_DECL for it. If for
4471 an aggregate, get a null pointer of the appropriate type and
4472 dereference it. */
4476 integer_zero_node));
4477 else
4478 {
4481 }
4487 /* We should only do this if we are just elaborating for side-effects,
4488 but we can't know that yet. */
4493 /* If we're taking the address of a constant CONSTRUCTOR, force it to
4494 be put into static memory. We know it's going to be readonly given
4495 the semantics we have and it's required to be static memory in
4496 the case when the reference is in an elaboration procedure. */
4499 {
4500 tree new_var
4510 }
4514 /* We have a kludge here. If the FIELD_DECL is from a fat pointer and is
4515 from an early dummy type, replace it with the proper FIELD_DECL. */
4518 {
4522 }
4524 /* ... fall through ... */
4528 }
4529 }
4531 /* Generate GIMPLE in place for the statement at *STMT_P. */
4533 static enum gimplify_status
4535 {
4539 {
4549 {
4553 /* Set to emit the statements of the loop. */
4556 /* We first emit the start label and then a conditional jump to
4557 the end label if there's a top condition, then the body of the
4558 loop, then a conditional branch to the end label, then the update,
4559 if any, and finally a jump to the start label and the definition
4560 of the end label. */
4562 gnu_start_label),
4563 stmt_p);
4570 void_type_node,
4571 gnu_end_label)),
4572 stmt_p);
4581 void_type_node,
4582 gnu_end_label)),
4583 stmt_p);
4589 gnu_start_label),
4590 stmt_p);
4592 gnu_end_label),
4593 stmt_p);
4595 }
4598 /* Build a statement to jump to the corresponding end label, then
4599 see if it needs to be conditional. */
4608 }
4609 }
4610 \f
4611 /* Force references to each of the entities in packages GNAT_NODE with's
4612 so that the debugging information for all of them are identical
4613 in all clients. Operate recursively on anything it with's, but check
4614 that we aren't elaborating something more than once. */
4616 /* The reason for this routine's existence is two-fold.
4617 First, with some debugging formats, notably MDEBUG on SGI
4618 IRIX, the linker will remove duplicate debugging information if two
4619 clients have identical debugguing information. With the normal scheme
4620 of elaboration, this does not usually occur, since entities in with'ed
4621 packages are elaborated on demand, and if clients have different usage
4622 patterns, the normal case, then the order and selection of entities
4623 will differ. In most cases however, it seems that linkers do not know
4624 how to eliminate duplicate debugging information, even if it is
4625 identical, so the use of this routine would increase the total amount
4626 of debugging information in the final executable.
4628 Second, this routine is called in type_annotate mode, to compute DDA
4629 information for types in withed units, for ASIS use */
4631 static void
4633 {
4636 /* Process each unit only once. As we trace the context of all relevant
4637 units transitively, including generic bodies, we may encounter the
4638 same generic unit repeatedly */
4643 /* Save entities in all context units. A body may have an implicit_with
4644 on its own spec, if the context includes a child unit, so don't save
4645 the spec twice. */
4653 {
4657 {
4674 }
4676 {
4677 Node_Id gnat_body
4680 /* Retrieve compilation unit node of generic body. */
4685 /* If body is available, elaborate its context. */
4688 }
4689 }
4693 }
4694 \f
4695 /* Do the processing of N_Freeze_Entity, GNAT_NODE. */
4697 static void
4699 {
4701 tree gnu_old;
4702 tree gnu_new;
4703 tree gnu_init
4708 /* If this is a package, need to generate code for the package. */
4710 {
4711 insert_code_for
4715 }
4717 /* Check for old definition after the above call. This Freeze_Node
4718 might be for one its Itypes. */
4719 gnu_old
4722 /* If this entity has an Address representation clause, GNU_OLD is the
4723 address, so discard it here. */
4727 /* Don't do anything for class-wide types they are always
4728 transformed into their root type. */
4734 /* Don't do anything for subprograms that may have been elaborated before
4735 their freeze nodes. This can happen, for example because of an inner call
4736 in an instance body. */
4743 /* If we have a non-dummy type old tree, we have nothing to do. Unless
4744 this is the public view of a private type whose full view was not
4745 delayed, this node was never delayed as it should have been.
4746 Also allow this to happen for concurrent types since we may have
4747 frozen both the Corresponding_Record_Type and this type. */
4751 {
4757 }
4759 /* Reset the saved tree, if any, and elaborate the object or type for real.
4760 If there is a full declaration, elaborate it and copy the type to
4761 GNAT_ENTITY. Likewise if this is the record subtype corresponding to
4762 a class wide type or subtype. */
4764 {
4773 }
4777 {
4780 /* The above call may have defined this entity (the simplest example
4781 of this is when we have a private enumeral type since the bounds
4782 will have the public view. */
4788 }
4789 else
4792 /* If we've made any pointers to the old version of this type, we
4793 have to update them. */
4797 }
4798 \f
4799 /* Process the list of inlined subprograms of GNAT_NODE, which is an
4800 N_Compilation_Unit. */
4802 static void
4804 {
4805 Entity_Id gnat_entity;
4806 Node_Id gnat_body;
4808 /* If we can inline, generate RTL for all the inlined subprograms.
4809 Define the entity first so we set DECL_EXTERNAL. */
4814 {
4818 {
4819 /* ??? This really should always be Present. */
4823 gnat_body
4825 }
4828 {
4831 }
4832 }
4833 }
4834 \f
4835 /* Elaborate decls in the lists GNAT_DECLS and GNAT_DECLS2, if present.
4836 We make two passes, one to elaborate anything other than bodies (but
4837 we declare a function if there was no spec). The second pass
4838 elaborates the bodies.
4840 GNAT_END_LIST gives the element in the list past the end. Normally,
4841 this is Empty, but can be First_Real_Statement for a
4842 Handled_Sequence_Of_Statements.
4844 We make a complete pass through both lists if PASS1P is true, then make
4845 the second pass over both lists if PASS2P is true. The lists usually
4846 correspond to the public and private parts of a package. */
4848 static void
4851 {
4853 Node_Id gnat_decl;
4863 {
4864 /* For package specs, we recurse inside the declarations,
4865 thus taking the two pass approach inside the boundary. */
4873 /* Similarly for any declarations in the actions of a
4874 freeze node. */
4876 {
4879 }
4881 /* Package bodies with freeze nodes get their elaboration deferred
4882 until the freeze node, but the code must be placed in the right
4883 place, so record the code position now. */
4891 (Corresponding_Spec
4894 record_code_position
4897 /* We defer most subprogram bodies to the second pass. */
4899 {
4901 {
4907 }
4908 }
4909 /* For bodies and stubs that act as their own specs, the entity
4910 itself must be elaborated in the first pass, because it may
4911 be used in other declarations. */
4913 {
4914 Node_Id gnat_subprog_id =
4921 }
4923 /* Concurrent stubs stand for the corresponding subprogram bodies,
4924 which are deferred like other bodies. */
4927 ;
4928 else
4930 }
4932 /* Here we elaborate everything we deferred above except for package bodies,
4933 which are elaborated at their freeze nodes. Note that we must also
4934 go inside things (package specs and freeze nodes) the first pass did. */
4940 {
4956 }
4957 }
4958 \f
4959 /* Emit code for a range check. GNU_EXPR is the expression to be checked,
4960 GNAT_RANGE_TYPE the gnat type or subtype containing the bounds against
4961 which we have to check. */
4963 static tree
4965 {
4971 /* If GNU_EXPR has an integral type that is narrower than GNU_RANGE_TYPE,
4972 we can't do anything since we might be truncating the bounds. No
4973 check is needed in this case. */
4979 /* Checked expressions must be evaluated only once. */
4982 /* There's no good type to use here, so we might as well use
4983 integer_type_node. Note that the form of the check is
4984 (not (expr >= lo)) or (not (expr >= hi))
4985 the reason for this slightly convoluted form is that NaN's
4986 are not considered to be in range in the float case. */
4987 return emit_check
4989 invert_truthvalue
4993 invert_truthvalue
4997 gnu_high)))),
4999 }
5000 \f
5001 /* Emit code for an index check. GNU_ARRAY_OBJECT is the array object
5002 which we are about to index, GNU_EXPR is the index expression to be
5003 checked, GNU_LOW and GNU_HIGH are the lower and upper bounds
5004 against which GNU_EXPR has to be checked. Note that for index
5005 checking we cannot use the emit_range_check function (although very
5006 similar code needs to be generated in both cases) since for index
5007 checking the array type against which we are checking the indeces
5008 may be unconstrained and consequently we need to retrieve the
5009 actual index bounds from the array object itself
5010 (GNU_ARRAY_OBJECT). The place where we need to do that is in
5011 subprograms having unconstrained array formal parameters */
5013 static tree
5015 tree gnu_expr,
5016 tree gnu_low,
5017 tree gnu_high)
5018 {
5019 tree gnu_expr_check;
5021 /* Checked expressions must be evaluated only once. */
5024 /* Must do this computation in the base type in case the expression's
5025 type is an unsigned subtypes. */
5028 /* If GNU_LOW or GNU_HIGH are a PLACEHOLDER_EXPR, qualify them by
5029 the object we are handling. */
5033 /* There's no good type to use here, so we might as well use
5034 integer_type_node. */
5035 return emit_check
5038 gnu_expr_check,
5040 gnu_low)),
5042 gnu_expr_check,
5044 gnu_high))),
5046 }
5047 \f
5048 /* GNU_COND contains the condition corresponding to an access, discriminant or
5049 range check of value GNU_EXPR. Build a COND_EXPR that returns GNU_EXPR if
5050 GNU_COND is false and raises a CONSTRAINT_ERROR if GNU_COND is true.
5051 REASON is the code that says why the exception was raised. */
5053 static tree
5055 {
5056 tree gnu_call;
5057 tree gnu_result;
5061 /* Use an outer COMPOUND_EXPR to make sure that GNU_EXPR will get evaluated
5062 in front of the comparison in case it ends up being a SAVE_EXPR. Put the
5063 whole thing inside its own SAVE_EXPR so the inner SAVE_EXPR doesn't leak
5064 out. */
5068 gnu_expr));
5070 /* If GNU_EXPR has side effects, make the outer COMPOUND_EXPR and
5071 protect it. Otherwise, show GNU_RESULT has no side effects: we
5072 don't need to evaluate it just for the check. */
5074 gnu_result
5076 else
5079 /* ??? Unfortunately, if we don't put a SAVE_EXPR around this whole thing,
5080 we will repeatedly do the test. It would be nice if GCC was able
5081 to optimize this and only do it once. */
5083 }
5084 \f
5085 /* Return an expression that converts GNU_EXPR to GNAT_TYPE, doing
5086 overflow checks if OVERFLOW_P is nonzero and range checks if
5087 RANGE_P is nonzero. GNAT_TYPE is known to be an integral type.
5088 If TRUNCATE_P is nonzero, do a float to integer conversion with
5089 truncation; otherwise round. */
5091 static tree
5094 {
5102 /* If we are not doing any checks, the output is an integral type, and
5103 the input is not a floating type, just do the conversion. This
5104 shortcut is required to avoid problems with packed array types
5105 and simplifies code in all cases anyway. */
5110 /* First convert the expression to its base type. This
5111 will never generate code, but makes the tests below much simpler.
5112 But don't do this if converting from an integer type to an unconstrained
5113 array type since then we need to get the bounds from the original
5114 (unpacked) type. */
5118 /* If overflow checks are requested, we need to be sure the result will
5119 fit in the output base type. But don't do this if the input
5120 is integer and the output floating-point. */
5123 {
5124 /* Ensure GNU_EXPR only gets evaluated once. */
5132 /* Convert the lower bounds to signed types, so we're sure we're
5133 comparing them properly. Likewise, convert the upper bounds
5134 to unsigned types. */
5148 /* Check each bound separately and only if the result bound
5149 is tighter than the bound on the input type. Note that all the
5150 types are base types, so the bounds must be constant. Also,
5151 the comparison is done in the base type of the input, which
5152 always has the proper signedness. First check for input
5153 integer (which means output integer), output float (which means
5154 both float), or mixed, in which case we always compare.
5155 Note that we have to do the comparison which would *fail* in the
5156 case of an error since if it's an FP comparison and one of the
5157 values is a NaN or Inf, the comparison will fail. */
5164 gnu_cond
5165 = invert_truthvalue
5168 gnu_out_lb)));
5176 gnu_cond
5178 invert_truthvalue
5180 gnu_input,
5182 gnu_out_ub))));
5186 CE_Overflow_Check_Failed);
5187 }
5189 /* Now convert to the result base type. If this is a non-truncating
5190 float-to-integer conversion, round. */
5193 {
5203 gnu_result
5205 }
5211 else
5214 /* Finally, do the range check if requested. Note that if the
5215 result type is a modular type, the range check is actually
5216 an overflow check. */
5224 }
5225 \f
5226 /* Return 1 if GNU_EXPR can be directly addressed. This is the case unless
5227 it is an expression involving computation or if it involves a bitfield
5228 reference. This returns the same as gnat_mark_addressable in most
5229 cases. */
5231 static bool
5233 {
5235 {
5240 /* All DECLs are addressable: if they are in a register, we can force
5241 them to memory. */
5267 {
5268 /* This is addressable if we can avoid a copy. */
5282 }
5286 }
5287 }
5288 \f
5289 /* Do the processing for the declaration of a GNAT_ENTITY, a type. If
5290 a separate Freeze node exists, delay the bulk of the processing. Otherwise
5291 make a GCC type for GNAT_ENTITY and set up the correspondance. */
5293 void
5295 {
5296 tree gnu_old
5298 tree gnu_new;
5300 /* If we are to delay elaboration of this type, just do any
5301 elaborations needed for expressions within the declaration and
5302 make a dummy type entry for this node and its Full_View (if
5303 any) in case something points to it. Don't do this if it
5304 has already been done (the only way that can happen is if
5305 the private completion is also delayed). */
5311 {
5315 {
5324 }
5327 }
5329 /* If we saved away a dummy type for this node it means that this
5330 made the type that corresponds to the full type of an incomplete
5331 type. Clear that type for now and then update the type in the
5332 pointers. */
5334 {
5337 {
5338 /* If this was a withed access type, this is not an error
5339 and merely indicates we've already elaborated the type
5340 already. */
5343 }
5346 }
5348 /* Now fully elaborate the type. */
5352 /* If we have an old type and we've made pointers to this type,
5353 update those pointers. */
5358 /* If this is a record type corresponding to a task or protected type
5359 that is a completion of an incomplete type, perform a similar update
5360 on the type. */
5361 /* ??? Including protected types here is a guess. */
5366 {
5367 tree gnu_task_old
5377 }
5378 }
5379 \f
5380 /* GNAT_ASSOC is the front of the Component_Associations of an N_Aggregate.
5381 GNU_TYPE is the GCC type of the corresponding record.
5383 Return a CONSTRUCTOR to build the record. */
5385 static tree
5387 {
5390 /* We test for GNU_FIELD being empty in the case where a variant
5391 was the last thing since we don't take things off GNAT_ASSOC in
5392 that case. We check GNAT_ASSOC in case we have a variant, but it
5393 has no fields. */
5397 {
5402 /* The expander is supposed to put a single component selector name
5403 in every record component association */
5406 /* Before assigning a value in an aggregate make sure range checks
5407 are done if required. Then convert to the type of the field. */
5413 /* Add the field and expression to the list. */
5415 }
5419 #ifdef ENABLE_CHECKING
5420 {
5421 tree gnu_field;
5423 /* Verify every enty in GNU_LIST was used. */
5426 }
5427 #endif
5430 }
5432 /* Builds a possibly nested constructor for array aggregates. GNAT_EXPR
5433 is the first element of an array aggregate. It may itself be an
5434 aggregate (an array or record aggregate). GNU_ARRAY_TYPE is the gnu type
5435 corresponding to the array aggregate. GNAT_COMPONENT_TYPE is the type
5436 of the array component. It is needed for range checking. */
5438 static tree
5440 Entity_Id gnat_component_type)
5441 {
5444 tree gnu_expr;
5447 {
5448 /* If the expression is itself an array aggregate then first build the
5449 innermost constructor if it is part of our array (multi-dimensional
5450 case). */
5457 gnat_component_type);
5458 else
5459 {
5462 /* before assigning the element to the array make sure it is
5463 in range */
5466 }
5468 gnu_expr_list
5470 gnu_expr_list);
5473 }
5476 }
5477 \f
5478 /* Subroutine of assoc_to_constructor: VALUES is a list of field associations,
5479 some of which are from RECORD_TYPE. Return a CONSTRUCTOR consisting
5480 of the associations that are from RECORD_TYPE. If we see an internal
5481 record, make a recursive call to fill it in as well. */
5483 static tree
5485 {
5490 {
5493 /* _Parent is an internal field, but may have values in the aggregate,
5494 so check for values first. */
5496 {
5499 }
5502 {
5506 }
5507 else
5508 /* If we have a record subtype, the names will match, but not the
5509 actual FIELD_DECLs. */
5512 {
5515 }
5521 }
5524 }
5525 \f
5526 /* EXP is to be treated as an array or record. Handle the cases when it is
5527 an access object and perform the required dereferences. */
5529 static tree
5531 {
5532 /* If the type is a pointer, dereference it. */
5537 /* If we got a padded type, remove it too. */
5543 }
5544 \f
5545 /* Protect EXP from multiple evaluation. This may make a SAVE_EXPR. */
5547 tree
5549 {
5552 /* If this has no side effects, we don't need to do anything. */
5556 /* If it is a conversion, protect what's inside the conversion.
5557 Similarly, if we're indirectly referencing something, we only
5558 actually need to protect the address since the data itself can't
5559 change in these situations. */
5568 /* If EXP is a fat pointer or something that can be placed into a register,
5569 just make a SAVE_EXPR. */
5573 /* Otherwise, dereference, protect the address, and re-reference. */
5574 else
5575 return
5579 exp)));
5580 }
5581 \f
5582 /* This is equivalent to stabilize_reference in GCC's tree.c, but we know
5583 how to handle our new nodes and we take an extra argument that says
5584 whether to force evaluation of everything. */
5586 tree
5588 {
5591 tree result;
5594 {
5598 /* No action is needed in this case. */
5610 result
5619 force));
5625 force),
5633 force),
5635 force));
5643 force),
5650 force),
5652 force));
5655 /* If arg isn't a kind of lvalue we recognize, make no change.
5656 Caller should recognize the error for an invalid lvalue. */
5662 }
5666 /* TREE_THIS_VOLATILE and TREE_SIDE_EFFECTS attached to the initial
5667 expression may not be sustained across some paths, such as the way via
5668 build1 for INDIRECT_REF. We re-populate those flags here for the general
5669 case, which is consistent with the GCC version of this routine.
5671 Special care should be taken regarding TREE_SIDE_EFFECTS, because some
5672 paths introduce side effects where there was none initially (e.g. calls
5673 to save_expr), and we also want to keep track of that. */
5679 }
5681 /* Similar to stabilize_reference_1 in tree.c, but supports an extra
5682 arg to force a SAVE_EXPR for everything. */
5684 static tree
5686 {
5689 tree result;
5691 /* We cannot ignore const expressions because it might be a reference
5692 to a const array but whose index contains side-effects. But we can
5693 ignore things that are actual constant or that already have been
5694 handled by this function. */
5700 {
5708 /* If this is a COMPONENT_REF of a fat pointer, save the entire
5709 fat pointer. This may be more efficient, but will also allow
5710 us to more easily find the match for the PLACEHOLDER_EXPR. */
5715 force),
5719 else
5724 /* Constants need no processing. In fact, we should never reach
5725 here. */
5729 /* Recursively stabilize each operand. */
5733 force));
5737 /* Recursively stabilize each operand. */
5740 force));
5745 }
5752 }
5753 \f
5756 /* Convert Sloc into *LOCUS (a location_t). Return true if this Sloc
5757 corresponds to a source code location and false if it doesn't. In the
5758 latter case, we don't update *LOCUS. We also set the Gigi global variable
5759 REF_FILENAME to the reference file name as given by sinput (i.e no
5760 directory). */
5762 bool
5764 {
5765 /* If node not from source code, ignore. */
5769 /* Use the identifier table to make a hashed, permanent copy of the filename,
5770 since the name table gets reallocated after Gigi returns but before all
5771 the debugging information is output. The __gnat_to_canonical_file_spec
5772 call translates filenames from pragmas Source_Reference that contain host
5773 style syntax not understood by gdb. */
5774 locus->file
5775 = IDENTIFIER_POINTER
5776 (get_identifier
5777 (__gnat_to_canonical_file_spec
5782 ref_filename
5783 = IDENTIFIER_POINTER
5784 (get_identifier
5788 }
5790 /* Similar to annotate_with_locus, but start with the Sloc of GNAT_NODE and
5791 don't do anything if it doesn't correspond to a source location. */
5793 static void
5795 {
5796 location_t locus;
5802 }
5803 \f
5804 /* Post an error message. MSG is the error message, properly annotated.
5805 NODE is the node at which to post the error and the node to use for the
5806 "&" substitution. */
5808 void
5810 {
5811 String_Template temp;
5812 Fat_Pointer fp;
5818 }
5820 /* Similar, but NODE is the node at which to post the error and ENT
5821 is the node to use for the "&" substitution. */
5823 void
5825 {
5826 String_Template temp;
5827 Fat_Pointer fp;
5833 }
5835 /* Similar, but NODE is the node at which to post the error, ENT is the node
5836 to use for the "&" substitution, and N is the number to use for the ^. */
5838 void
5840 {
5841 String_Template temp;
5842 Fat_Pointer fp;
5850 }
5851 \f
5852 /* Similar to post_error_ne_num, but T is a GCC tree representing the
5853 number to write. If the tree represents a constant that fits within
5854 a host integer, the text inside curly brackets in MSG will be output
5855 (presumably including a '^'). Otherwise that text will not be output
5856 and the text inside square brackets will be output instead. */
5858 void
5860 {
5863 Fat_Pointer fp;
5871 #if HOST_BITS_PER_WIDE_INT > HOST_BITS_PER_INT
5872 &&
5873 compare_tree_int
5875 #endif
5876 )
5877 {
5880 }
5881 else
5885 {
5891 ;
5892 else
5894 }
5901 }
5903 /* Similar to post_error_ne_tree, except that NUM is a second
5904 integer to write in the message. */
5906 void
5908 Node_Id node,
5909 Entity_Id ent,
5910 tree t,
5912 {
5915 }
5917 /* Set the node for a second '&' in the error message. */
5919 void
5921 {
5923 }
5924 \f
5925 /* Initialize the table that maps GNAT codes to GCC codes for simple
5926 binary and unary operations. */
5928 void
5930 {
5956 }