| blob | fb741a3e03081409cfc78c80de97f7e8d79c0592 |
1 /****************************************************************************
2 * *
3 * GNAT COMPILER COMPONENTS *
4 * *
5 * T R A N S *
6 * *
7 * C Implementation File *
8 * *
9 * Copyright (C) 1992-2005, Free Software Foundation, Inc. *
10 * *
11 * GNAT is free software; you can redistribute it and/or modify it under *
12 * terms of the GNU General Public License as published by the Free Soft- *
13 * ware Foundation; either version 2, or (at your option) any later ver- *
14 * sion. GNAT is distributed in the hope that it will be useful, but WITH- *
15 * OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY *
16 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License *
17 * for more details. You should have received a copy of the GNU General *
18 * Public License distributed with GNAT; see file COPYING. If not, write *
19 * to the Free Software Foundation, 51 Franklin Street, Fifth Floor, *
20 * Boston, MA 02110-1301, 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 ****************************************************************************/
71 /* Current filename without path. */
74 /* If true, then gigi is being called on an analyzed but unexpanded
75 tree, and the only purpose of the call is to properly annotate
76 types with representation information. */
79 /* A structure used to gather together information about a statement group.
80 We use this to gather related statements, for example the "then" part
81 of a IF. In the case where it represents a lexical scope, we may also
82 have a BLOCK node corresponding to it and/or cleanups. */
89 };
93 /* List of unused struct stmt_group nodes. */
96 /* A structure used to record information on elaboration procedures
97 we've made and need to process.
99 ??? gnat_node should be Node_Id, but gengtype gets confused. */
105 };
109 /* Free list of TREE_LIST nodes used for stacks. */
112 /* List of TREE_LIST nodes representing a stack of exception pointer
113 variables. TREE_VALUE is the VAR_DECL that stores the address of
114 the raised exception. Nonzero means we are in an exception
115 handler. Not used in the zero-cost case. */
118 /* List of TREE_LIST nodes used to store the current elaboration procedure
119 decl. TREE_VALUE is the decl. */
122 /* Variable that stores a list of labels to be used as a goto target instead of
123 a return in some functions. See processing for N_Subprogram_Body. */
126 /* List of TREE_LIST nodes representing a stack of LOOP_STMT nodes.
127 TREE_VALUE of each entry is the label of the corresponding LOOP_STMT. */
130 /* List of TREE_LIST nodes representing labels for switch statements.
131 TREE_VALUE of each entry is the label at the end of the switch. */
134 /* Map GNAT tree codes to GCC tree codes for simple expressions. */
137 /* Current node being treated, in case abort called. */
138 Node_Id error_gnat_node;
170 \f
171 /* This is the main program of the back-end. It sets up all the table
172 structures and then generates code. */
174 void
182 Int gigi_operating_mode)
183 {
184 tree gnu_standard_long_long_float;
185 tree gnu_standard_exception_type;
205 /* If we are just annotating types, give VOID_TYPE zero sizes to avoid
206 errors. */
208 {
211 }
213 /* Save the type we made for integer as the type for Standard.Integer.
214 Then make the rest of the standard types. Note that some of these
215 may be subtypes. */
221 gnu_standard_long_long_float
223 gnu_standard_exception_type
228 /* Process any Pragma Ident for the main unit. */
229 #ifdef ASM_OUTPUT_IDENT
231 ASM_OUTPUT_IDENT
234 #endif
236 /* If we are using the GCC exception mechanism, let GCC know. */
243 /* Now see if we have any elaboration procedures to deal with. */
245 {
247 tree gnu_stmts;
249 /* Mark everything we have as not visited. */
252 /* Set the current function to be the elaboration procedure and gimplify
253 what we have. */
257 /* We should have a BIND_EXPR, but it may or may not have any statements
258 in it. If it doesn't have any, we have nothing to do. */
263 /* If there are no statements, there is no elaboration code. */
266 else
267 {
268 /* Otherwise, compile the function. Note that we'll be gimplifying
269 it twice, but that's fine for the nodes we use. */
272 }
273 }
274 }
275 \f
276 /* Perform initializations for this module. */
278 void
280 {
281 /* Initialize ourselves. */
285 /* Enable GNAT stack checking method if needed */
288 }
289 \f
290 /* Subroutine of gnat_to_gnu to translate gnat_node, an N_Identifier,
291 to a GCC tree, which is returned. GNU_RESULT_TYPE_P is a pointer to
292 where we should place the result type. */
294 static tree
296 {
297 tree gnu_result_type;
298 tree gnu_result;
301 /* If the Etype of this node does not equal the Etype of the Entity,
302 something is wrong with the entity map, probably in generic
303 instantiation. However, this does not apply to types. Since we sometime
304 have strange Ekind's, just do this test for objects. Also, if the Etype of
305 the Entity is private, the Etype of the N_Identifier is allowed to be the
306 full type and also we consider a packed array type to be the same as the
307 original type. Similarly, a class-wide type is equivalent to a subtype of
308 itself. Finally, if the types are Itypes, one may be a copy of the other,
309 which is also legal. */
332 /* If this is a reference to a deferred constant whose partial view is an
333 unconstrained private type, the proper type is on the full view of the
334 constant, not on the full view of the type, which may be unconstrained.
336 This may be a reference to a type, for example in the prefix of the
337 attribute Position, generated for dispatching code (see Make_DT in
338 exp_disp,adb). In that case we need the type itself, not is parent,
339 in particular if it is a derived type */
344 {
348 }
349 else
350 {
351 /* Expand the type of this identifier first, in case it is an enumeral
352 literal, which only get made when the type is expanded. There is no
353 order-of-elaboration issue here. We want to use the Actual_Subtype if
354 it has already been elaborated, otherwise the Etype. Avoid using
355 Actual_Subtype for packed arrays to simplify things. */
363 else
367 }
371 /* If we are in an exception handler, force this variable into memory to
372 ensure optimization does not remove stores that appear redundant but are
373 actually needed in case an exception occurs.
375 ??? Note that we need not do this if the variable is declared within the
376 handler, only if it is referenced in the handler and declared in an
377 enclosing block, but we have no way of testing that right now.
379 ??? Also, for now all we can do is make it volatile. But we only
380 do this for SJLJ. */
385 /* Some objects (such as parameters passed by reference, globals of
386 variable size, and renamed objects) actually represent the address
387 of the object. In that case, we must do the dereference. Likewise,
388 deal with parameters to foreign convention subprograms. Call fold
389 here since GNU_RESULT may be a CONST_DECL. */
394 {
396 tree renamed_obj;
400 gnu_result
403 gnu_result));
405 /* If it's a renaming pointer and we are at the right binding level,
406 we can reference the renamed object directly, since the renamed
407 expression has been protected against multiple evaluations. */
412 /* Make sure it's an lvalue like INDIRECT_REF. */
419 else
424 }
426 /* The GNAT tree has the type of a function as the type of its result. Also
427 use the type of the result if the Etype is a subtype which is nominally
428 unconstrained. But remove any padding from the resulting type. */
431 {
436 }
438 /* We always want to return the underlying INTEGER_CST for an enumeration
439 literal to avoid the need to call fold in lots of places. But don't do
440 this is the parent will be taking the address of this object. */
442 {
456 }
460 }
461 \f
462 /* Subroutine of gnat_to_gnu to process gnat_node, an N_Pragma. Return
463 any statements we generate. */
465 static tree
467 {
468 Node_Id gnat_temp;
471 /* Check for (and ignore) unrecognized pragma and do nothing if we are just
472 annotating types. */
477 {
479 /* Do nothing at top level: all such variables are already viewable. */
486 {
495 }
501 {
514 }
521 }
524 }
525 /* Subroutine of gnat_to_gnu to translate gnat_node, an N_Attribute,
526 to a GCC tree, which is returned. GNU_RESULT_TYPE_P is a pointer to
527 where we should place the result type. ATTRIBUTE is the attribute ID. */
529 static tree
531 {
533 tree gnu_result_type;
534 tree gnu_expr;
539 /* If the input is a NULL_EXPR, make a new one. */
541 {
545 }
548 {
551 /* These are just conversions until since representation clauses for
552 enumerations are handled in the front end. */
553 {
560 }
565 /* These just add or subject the constant 1. Representation clauses for
566 enumerations are handled in the front-end. */
571 {
573 gnu_expr
574 = emit_check
576 gnu_expr,
577 attribute == Attr_Pred
581 }
583 gnu_result
592 /* Conversions don't change something's address but can cause us to miss
593 the COMPONENT_REF case below, so strip them off. */
597 /* If we are taking 'Address of an unconstrained object, this is the
598 pointer to the underlying array. */
602 /* ... fall through ... */
608 gnu_result
615 /* For 'Code_Address, find an inner ADDR_EXPR and mark it so that we
616 don't try to build a trampoline. */
618 {
627 }
631 {
632 tree gnu_obj_type;
637 /* If this is an unconstrained array, we know the object must have been
638 allocated with the template in front of the object. So compute the
639 template address.*/
641 gnu_ptr
643 (TYPE_OBJECT_RECORD_TYPE
645 gnu_ptr);
650 {
653 tree gnu_byte_offset
660 }
663 }
672 /* Remove NOPS from gnu_expr and conversions from gnu_prefix.
673 We only use GNU_EXPR to see if a COMPONENT_REF was involved. */
676 ;
682 /* Replace an unconstrained array type with the type of the underlying
683 array. We can't do this with a call to maybe_unconstrained_array
684 since we may have a TYPE_DECL. For 'Max_Size_In_Storage_Elements,
685 use the record type that will be used to allocate the object and its
686 template. */
688 {
692 }
694 /* If we're looking for the size of a field, return the field size.
695 Otherwise, if the prefix is an object, or if 'Object_Size or
696 'Max_Size_In_Storage_Elements has been specified, the result is the
697 GCC size of the type. Otherwise, the result is the RM_Size of the
698 type. */
704 {
705 /* If this is a padded type, the GCC size isn't relevant to the
706 programmer. Normally, what we want is the RM_Size, which was set
707 from the specified size, but if it was not set, we want the size
708 of the relevant field. Using the MAX of those two produces the
709 right result in all case. Don't use the size of the field if it's
710 a self-referential type, since that's never what's wanted. */
714 {
718 gnu_result
721 }
722 else
724 }
725 else
730 /* Deal with a self-referential size by returning the maximum size for a
731 type and by qualifying the size with the object for 'Size of an
732 object. */
734 {
737 else
739 }
741 /* If the type contains a template, subtract its size. */
749 /* Always perform division using unsigned arithmetic as the size cannot
750 be negative, but may be an overflowed positive value. This provides
751 correct results for sizes up to 512 MB.
753 ??? Size should be calculated in storage elements directly. */
774 else
784 {
791 else
792 gnu_result
793 = build_binary_op
795 build_binary_op
807 }
809 /* ... fall through ... */
812 {
817 /* Make sure any implicit dereference gets done. */
825 {
827 tree gnu_type_temp;
833 ;
836 }
843 gnu_result
846 gnu_result
848 else
849 /* 'Length or 'Range_Length. */
850 {
851 tree gnu_compute_type
855 gnu_result
856 = build_binary_op
858 build_binary_op
860 build_binary_op
863 TYPE_MAX_VALUE
866 TYPE_MIN_VALUE
870 }
872 /* If this has a PLACEHOLDER_EXPR, qualify it by the object we are
873 handling. Note that these attributes could not have been used on
874 an unconstrained array type. */
876 gnu_prefix);
878 }
885 {
886 HOST_WIDE_INT bitsize;
887 HOST_WIDE_INT bitpos;
888 tree gnu_offset;
889 tree gnu_field_bitpos;
890 tree gnu_field_offset;
891 tree gnu_inner;
899 /* We can have 'Bit on any object, but if it isn't a COMPONENT_REF,
900 the result is 0. Don't allow 'Bit on a bare component, though. */
904 {
907 }
909 else
918 {
926 {
927 gnu_field_bitpos
930 gnu_field_offset
933 }
934 }
936 {
939 }
940 else
941 {
944 }
947 {
962 bitsize_one_node);
968 }
970 /* If this has a PLACEHOLDER_EXPR, qualify it by the object
971 we are handling. */
974 }
978 {
986 }
1014 /* Note this size cannot be self-referential. */
1021 /* This is just a zero cast to the pointer type for
1022 our prefix and dereferenced. */
1024 gnu_result
1027 integer_zero_node));
1032 {
1039 {
1044 ;
1045 }
1053 && (DECL_BY_COMPONENT_PTR_P
1057 }
1061 /* Say we have an unimplemented attribute. Then set the value to be
1062 returned to be a zero and hope that's something we can convert to the
1063 type of this attribute. */
1068 }
1070 /* If this is an attribute where the prefix was unused, force a use of it if
1071 it has a side-effect. But don't do it if the prefix is just an entity
1072 name. However, if an access check is needed, we must do it. See second
1073 example in AARM 11.6(5.e). */
1081 }
1082 \f
1083 /* Subroutine of gnat_to_gnu to translate gnat_node, an N_Case_Statement,
1084 to a GCC tree, which is returned. */
1086 static tree
1088 {
1089 tree gnu_result;
1090 tree gnu_expr;
1091 Node_Id gnat_when;
1096 /* The range of values in a case statement is determined by the rules in
1097 RM 5.4(7-9). In almost all cases, this range is represented by the Etype
1098 of the expression. One exception arises in the case of a simple name that
1099 is parenthesized. This still has the Etype of the name, but since it is
1100 not a name, para 7 does not apply, and we need to go to the base type.
1101 This is the only case where parenthesization affects the dynamic
1102 semantics (i.e. the range of possible values at runtime that is covered
1103 by the others alternative.
1105 Another exception is if the subtype of the expression is non-static. In
1106 that case, we also have to use the base type. */
1112 /* We build a SWITCH_EXPR that contains the code with interspersed
1113 CASE_LABEL_EXPRs for each label. */
1120 {
1121 Node_Id gnat_choice;
1123 /* First compile all the different case choices for the current WHEN
1124 alternative. */
1127 {
1131 {
1146 /* This represents either a subtype range or a static value of
1147 some kind; Ekind says which. If a static value, fall through
1148 to the next case. */
1150 {
1156 }
1158 /* ... fall through ... */
1170 }
1175 gnat_choice);
1176 }
1178 /* Push a binding level here in case variables are declared since we want
1179 them to be local to this set of statements instead of the block
1180 containing the Case statement. */
1184 }
1186 /* Now emit a definition of the label all the cases branched to. */
1194 }
1195 \f
1196 /* Subroutine of gnat_to_gnu to translate gnat_node, an N_Loop_Statement,
1197 to a GCC tree, which is returned. */
1199 static tree
1201 {
1202 /* ??? It would be nice to use "build" here, but there's no build5. */
1208 tree gnu_result;
1215 /* Save the end label of this LOOP_STMT in a stack so that the corresponding
1216 N_Exit_Statement can find it. */
1220 /* Set the condition that under which the loop should continue.
1221 For "LOOP .... END LOOP;" the condition is always true. */
1223 ;
1224 /* The case "WHILE condition LOOP ..... END LOOP;" */
1228 else
1229 {
1230 /* We have an iteration scheme. */
1245 /* We know the loop variable will not overflow if GNU_LAST is a constant
1246 and is not equal to GNU_LIMIT. If it might overflow, we have to move
1247 the limit test to the end of the loop. In that case, we have to test
1248 for an empty loop outside the loop. */
1252 {
1253 gnu_cond_expr
1259 }
1261 /* Open a new nesting level that will surround the loop to declare the
1262 loop index variable. */
1266 /* Declare the loop index and set it to its initial value. */
1271 /* The loop variable might be a padded type, so use `convert' to get a
1272 reference to the inner variable if so. */
1275 /* Set either the top or bottom exit condition as appropriate depending
1276 on whether or not we know an overflow cannot occur. */
1281 else
1290 gnu_loop_var,
1292 integer_one_node));
1294 gnat_iter_scheme);
1295 }
1297 /* If the loop was named, have the name point to this loop. In this case,
1298 the association is not a ..._DECL node, but the end label from this
1299 LOOP_STMT. */
1304 /* Make the loop body into its own block, so any allocated storage will be
1305 released every iteration. This is needed for stack allocation. */
1309 /* If we declared a variable, then we are in a statement group for that
1310 declaration. Add the LOOP_STMT to it and make that the "loop". */
1312 {
1316 }
1318 /* If we have an outer COND_EXPR, that's our result and this loop is its
1319 "true" statement. Otherwise, the result is the LOOP_STMT. */
1321 {
1325 }
1326 else
1332 }
1333 \f
1334 /* Subroutine of gnat_to_gnu to process gnat_node, an N_Subprogram_Body. We
1335 don't return anything. */
1337 static void
1339 {
1340 /* Save debug output mode in case it is reset. */
1343 /* Defining identifier of a parameter to the subprogram. */
1344 Entity_Id gnat_param;
1345 /* The defining identifier for the subprogram body. Note that if a
1346 specification has appeared before for this body, then the identifier
1347 occurring in that specification will also be a defining identifier and all
1348 the calls to this subprogram will point to that specification. */
1349 Entity_Id gnat_subprog_id
1352 /* The FUNCTION_DECL node corresponding to the subprogram spec. */
1353 tree gnu_subprog_decl;
1354 /* The FUNCTION_TYPE node corresponding to the subprogram spec. */
1355 tree gnu_subprog_type;
1356 tree gnu_cico_list;
1357 tree gnu_result;
1359 /* If this is a generic object or if it has been eliminated,
1360 ignore it. */
1366 /* If debug information is suppressed for the subprogram, turn debug
1367 mode off for the duration of processing. */
1369 {
1372 }
1374 /* If this subprogram acts as its own spec, define it. Otherwise, just get
1375 the already-elaborated tree node. However, if this subprogram had its
1376 elaboration deferred, we will already have made a tree node for it. So
1377 treat it as not being defined in that case. Such a subprogram cannot
1378 have an address clause or a freeze node, so this test is safe, though it
1379 does disable some otherwise-useful error checking. */
1380 gnu_subprog_decl
1387 /* Set the line number in the decl to correspond to that of the body so that
1388 the line number notes are written
1389 correctly. */
1395 /* If there are OUT parameters, we need to ensure that the return statement
1396 properly copies them out. We do this by making a new block and converting
1397 any inner return into a goto to a label at the end of the block. */
1401 /* Get a tree corresponding to the code for the subprogram. */
1405 /* See if there are any parameters for which we don't yet have GCC entities.
1406 These must be for OUT parameters for which we will be making VAR_DECL
1407 nodes here. Fill them in to TYPE_CI_CO_LIST, which must contain the empty
1408 entry as well. We can match up the entries because TYPE_CI_CO_LIST is in
1409 the order of the parameters. */
1414 {
1415 /* Skip any entries that have been already filled in; they must
1416 correspond to IN OUT parameters. */
1419 ;
1421 /* Do any needed references for padded types. */
1425 }
1429 /* Generate the code of the subprogram itself. A return statement will be
1430 present and any OUT parameters will be handled there. */
1435 /* If we made a special return label, we need to make a block that contains
1436 the definition of that label and the copying to the return value. That
1437 block first contains the function, then the label and copy statement. */
1439 {
1440 tree gnu_retval;
1451 else
1453 gnu_cico_list);
1458 add_stmt_with_node
1462 gnat_node);
1465 }
1469 /* Initialize the information node for the function and set the
1470 end location. */
1472 Sloc_to_locus
1480 /* Disconnect the trees for parameters that we made variables for from the
1481 GNAT entities since these are unusable after we end the function. */
1491 }
1492 \f
1493 /* Subroutine of gnat_to_gnu to translate gnat_node, either an N_Function_Call
1494 or an N_Procedure_Call_Statement, to a GCC tree, which is returned.
1495 GNU_RESULT_TYPE_P is a pointer to where we should place the result type.
1496 If GNU_TARGET is non-null, this must be a function call and the result
1497 of the call is to be placed into that object. */
1499 static tree
1501 {
1502 tree gnu_result;
1503 /* The GCC node corresponding to the GNAT subprogram name. This can either
1504 be a FUNCTION_DECL node if we are dealing with a standard subprogram call,
1505 or an indirect reference expression (an INDIRECT_REF node) pointing to a
1506 subprogram. */
1508 /* The FUNCTION_TYPE node giving the GCC type of the subprogram. */
1511 gnu_subprog_node);
1512 Entity_Id gnat_formal;
1513 Node_Id gnat_actual;
1518 tree gnu_subprog_call;
1521 {
1528 }
1532 /* If we are calling a stubbed function, make this into a raise of
1533 Program_Error. Elaborate all our args first. */
1536 {
1543 {
1547 }
1548 else
1550 }
1552 /* If we are calling by supplying a pointer to a target, set up that
1553 pointer as the first argument. Use GNU_TARGET if one was passed;
1554 otherwise, make a target by building a variable of the maximum size
1555 of the type. */
1557 {
1558 tree gnu_real_ret_type
1562 {
1563 tree gnu_obj_type
1571 }
1573 gnu_actual_list
1577 gnu_target,
1579 NULL_TREE);
1581 }
1583 /* The only way we can be making a call via an access type is if Name is an
1584 explicit dereference. In that case, get the list of formal args from the
1585 type the access type is pointing to. Otherwise, get the formals from
1586 entity being called. */
1590 /* Assume here that this must be 'Elab_Body or 'Elab_Spec. */
1592 else
1595 /* Create the list of the actual parameters as GCC expects it, namely a chain
1596 of TREE_LIST nodes in which the TREE_VALUE field of each node is a
1597 parameter-expression and the TREE_PURPOSE field is null. Skip OUT
1598 parameters not passed by reference and don't need to be copied in. */
1603 {
1604 tree gnu_formal
1607 /* We treat a conversion between aggregate types as if it is an
1608 unchecked conversion. */
1609 bool unchecked_convert_p
1613 Node_Id gnat_name = (unchecked_convert_p
1617 tree gnu_actual;
1618 tree gnu_formal_type;
1620 /* If it's possible we may need to use this expression twice, make sure
1621 than any side-effects are handled via SAVE_EXPRs. Likewise if we need
1622 to force side-effects before the call.
1624 ??? This is more conservative than we need since we don't need to do
1625 this for pass-by-ref with no conversion. If we are passing a
1626 non-addressable Out or In Out parameter by reference, pass the address
1627 of a copy and set up to copy back out after the call. */
1629 {
1632 && gnu_formal
1637 {
1639 tree gnu_temp;
1641 /* For users of Starlet we issue a warning because the
1642 interface apparently assumes that by-ref parameters
1643 outlive the procedure invocation. The code still
1644 will not work as intended, but we cannot do much
1645 better since other low-level parts of the back-end
1646 would allocate temporaries at will because of the
1647 misalignment if we did not do so here. */
1650 {
1651 post_error
1653 gnat_actual);
1654 post_error_ne
1657 post_error_ne
1660 }
1662 /* Remove any unpadding on the actual and make a copy. But if
1663 the actual is a justified modular type, first convert
1664 to it. */
1668 && (TYPE_IS_PADDING_P
1677 /* Since we're going to take the address of the SAVE_EXPR, we
1678 don't want it to be marked as unchanging. So set
1679 TREE_ADDRESSABLE. */
1682 {
1685 }
1687 /* Set up to move the copy back to the original. */
1692 }
1693 }
1695 /* If this was a procedure call, we may not have removed any padding.
1696 So do it here for the part we will use as an input, if any. */
1702 gnu_actual);
1704 /* Unless this is an In parameter, we must remove any LJM building
1705 from GNU_NAME. */
1711 gnu_name);
1714 && !unchecked_convert_p
1718 /* Do any needed conversions. We need only check for unchecked
1719 conversion since normal conversions will be handled by just
1720 converting to the formal type. */
1722 {
1723 gnu_actual
1725 gnu_actual,
1730 /* One we've done the unchecked conversion, we still must ensure that
1731 the object is in range of the formal's type. */
1736 }
1738 /* We may have suppressed a conversion to the Etype of the actual since
1739 the parent is a procedure call. So add the conversion here. */
1741 gnu_actual);
1743 /* If we have not saved a GCC object for the formal, it means it is an
1744 OUT parameter not passed by reference and that does not need to be
1745 copied in. Otherwise, look at the PARM_DECL to see if it is passed by
1746 reference. */
1749 {
1751 {
1754 /* If we have a padded type, be sure we've removed padding. */
1759 gnu_actual);
1761 /* If we have the constructed subtype of an aliased object
1762 with an unconstrained nominal subtype, the type of the
1763 actual includes the template, although it is formally
1764 constrained. So we need to convert it back to the real
1765 constructed subtype to retrieve the constrained part
1766 and takes its address. */
1773 gnu_actual);
1774 }
1776 /* Otherwise, if we have a non-addressable COMPONENT_REF of a
1777 variable-size type see if it's doing a unpadding operation. If
1778 so, remove that operation since we have no way of allocating the
1779 required temporary. */
1789 /* The symmetry of the paths to the type of an entity is broken here
1790 since arguments don't know that they will be passed by ref. */
1793 }
1796 {
1803 {
1806 }
1808 /* Take the address of the object and convert to the proper pointer
1809 type. We'd like to actually compute the address of the beginning
1810 of the array using an ADDR_EXPR of an ARRAY_REF, but there's a
1811 possibility that the ARRAY_REF might return a constant and we'd be
1812 getting the wrong address. Neither approach is exactly correct,
1813 but this is the most likely to work in all cases. */
1816 gnu_actual));
1817 }
1820 {
1821 /* If arg is 'Null_Parameter, pass zero descriptor. */
1826 integer_zero_node);
1827 else
1830 gnat_formal));
1831 }
1832 else
1833 {
1842 /* If this is 'Null_Parameter, pass a zero even though we are
1843 dereferencing it. */
1848 BITS_PER_WORD))
1849 gnu_actual
1854 integer_zero_node),
1856 else
1858 }
1861 }
1865 NULL_TREE);
1867 /* If we return by passing a target, we emit the call and return the target
1868 as our result. */
1870 {
1872 *gnu_result_type_p
1875 }
1877 /* If it is a function call, the result is the call expression unless
1878 a target is specified, in which case we copy the result into the target
1879 and return the assignment statement. */
1881 {
1884 /* If the function returns an unconstrained array or by reference,
1885 we have to de-dereference the pointer. */
1893 else
1897 }
1899 /* If this is the case where the GNAT tree contains a procedure call
1900 but the Ada procedure has copy in copy out parameters, the special
1901 parameter passing mechanism must be used. */
1903 {
1904 /* List of FIELD_DECLs associated with the PARM_DECLs of the copy
1905 in copy out parameters. */
1910 {
1911 tree gnu_name;
1916 /* If any of the names had side-effects, ensure they are all
1917 evaluated before the call. */
1923 }
1927 else
1934 /* If we are dealing with a copy in copy out parameter, we must
1935 retrieve its value from the record returned in the call. */
1941 || (DECL_BY_DESCRIPTOR_P
1944 {
1945 /* Get the value to assign to this OUT or IN OUT parameter. It is
1946 either the result of the function if there is only a single such
1947 parameter or the appropriate field from the record returned. */
1948 tree gnu_result
1955 /* If the actual is a conversion, get the inner expression, which
1956 will be the real destination, and convert the result to the
1957 type of the actual parameter. */
1958 tree gnu_actual
1961 /* If the result is a padded type, remove the padding. */
1966 gnu_result);
1968 /* If the result is a type conversion, do it. */
1970 gnu_result
1971 = convert_with_check
1979 gnu_result,
1981 else
1982 {
1990 }
1998 }
1999 }
2000 else
2001 {
2004 }
2008 }
2009 \f
2010 /* Subroutine of gnat_to_gnu to translate gnat_node, an
2011 N_Handled_Sequence_Of_Statements, to a GCC tree, which is returned. */
2013 static tree
2015 {
2018 /* If just annotating, ignore all EH and cleanups. */
2022 bool setjmp_longjmp
2028 tree gnu_result;
2029 tree gnu_expr;
2030 Node_Id gnat_temp;
2032 /* The GCC exception handling mechanism can handle both ZCX and SJLJ schemes
2033 and we have our own SJLJ mechanism. To call the GCC mechanism, we call
2034 add_cleanup, and when we leave the binding, end_stmt_group will create
2035 the TRY_FINALLY_EXPR.
2037 ??? The region level calls down there have been specifically put in place
2038 for a ZCX context and currently the order in which things are emitted
2039 (region/handlers) is different from the SJLJ case. Instead of putting
2040 other calls with different conditions at other places for the SJLJ case,
2041 it seems cleaner to reorder things for the SJLJ case and generalize the
2042 condition to make it not ZCX specific.
2044 If there are any exceptions or cleanup processing involved, we need an
2045 outer statement group (for Setjmp_Longjmp) and binding level. */
2047 {
2050 }
2052 /* If we are to call a function when exiting this block add a cleanup
2053 to the binding level we made above. */
2057 /* If using setjmp_longjmp, make the variables for the setjmp buffer and save
2058 area for address of previous buffer. Do this first since we need to have
2059 the setjmp buf known for any decls in this block. */
2061 {
2066 gnat_node);
2074 /* When we exit this block, restore the saved value. */
2076 }
2078 /* Now build the tree for the declarations and statements inside this block.
2079 If this is SJLJ, set our jmp_buf as the current buffer. */
2085 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 {
2244 tree gnu_expr;
2246 /* Exception may be a renaming. Recover original exception which is
2247 the one elaborated and registered. */
2253 this_choice
2254 = build_binary_op
2259 /* If this is the distinguished exception "Non_Ada_Error" (and we are
2260 in VMS mode), also allow a non-Ada exception (a VMS condition) t
2261 match. */
2263 {
2264 tree gnu_comp
2265 = build_component_ref
2270 this_choice
2271 = build_binary_op
2275 this_choice);
2276 }
2277 }
2278 else
2283 }
2286 }
2287 \f
2288 /* Subroutine of gnat_to_gnu to translate gnat_node, an N_Exception_Handler,
2289 to a GCC tree, which is returned. This is the variant for ZCX. */
2291 static tree
2293 {
2295 tree gnu_expr;
2296 tree gnu_etype;
2297 tree gnu_current_exc_ptr;
2298 tree gnu_incoming_exc_ptr;
2299 Node_Id gnat_temp;
2301 /* We build a TREE_LIST of nodes representing what exception types this
2302 handler can catch, with special cases for others and all others cases.
2304 Each exception type is actually identified by a pointer to the exception
2305 id, or to a dummy object for "others" and "all others".
2307 Care should be taken to ensure that the control flow impact of "others"
2308 and "all others" is known to GCC. lang_eh_type_covers is doing the trick
2309 currently. */
2312 {
2314 {
2315 tree gnu_expr
2318 gnu_etype
2320 }
2323 {
2326 /* Exception may be a renaming. Recover original exception which is
2327 the one elaborated and registered. */
2334 /* The Non_Ada_Error case for VMS exceptions is handled
2335 by the personality routine. */
2336 }
2337 else
2340 /* The GCC interface expects NULL to be passed for catch all handlers, so
2341 it would be quite tempting to set gnu_etypes_list to NULL if gnu_etype
2342 is integer_zero_node. It would not work, however, because GCC's
2343 notion of "catch all" is stronger than our notion of "others". Until
2344 we correctly use the cleanup interface as well, doing that would
2345 prevent the "all others" handlers from being seen, because nothing
2346 can be caught beyond a catch all from GCC's point of view. */
2348 }
2353 /* Expand a call to the begin_handler hook at the beginning of the handler,
2354 and arrange for a call to the end_handler hook to occur on every possible
2355 exit path.
2357 The hooks expect a pointer to the low level occurrence. This is required
2358 for our stack management scheme because a raise inside the handler pushes
2359 a new occurrence on top of the stack, which means that this top does not
2360 necessarily match the occurrence this handler was dealing with.
2362 The EXC_PTR_EXPR object references the exception occurrence being
2363 propagated. Upon handler entry, this is the exception for which the
2364 handler is triggered. This might not be the case upon handler exit,
2365 however, as we might have a new occurrence propagated by the handler's
2366 body, and the end_handler hook called as a cleanup in this context.
2368 We use a local variable to retrieve the incoming value at handler entry
2369 time, and reuse it to feed the end_handler hook's argument at exit. */
2374 gnat_node);
2377 gnu_incoming_exc_ptr),
2378 gnat_node);
2385 }
2386 \f
2387 /* Subroutine of gnat_to_gnu to generate code for an N_Compilation unit. */
2389 static void
2391 {
2392 /* Make the decl for the elaboration procedure. */
2397 tree gnu_elab_proc_decl
2398 = create_subprog_decl
2402 gnat_unit_entity);
2412 /* For a body, first process the spec if there is one. */
2421 {
2428 }
2434 /* Process any pragmas and actions following the unit. */
2438 /* Save away what we've made so far and record this potential elaboration
2439 procedure. */
2449 /* Generate elaboration code for this unit, if necessary, and say whether
2450 we did or not. */
2453 /* Generate functions to call static constructors and destructors
2454 for targets that do not support .ctors/.dtors sections. These
2455 functions have magic names which are detected by collect2. */
2461 }
2462 \f
2463 /* This function is the driver of the GNAT to GCC tree transformation
2464 process. It is the entry point of the tree transformer. GNAT_NODE is the
2465 root of some GNAT tree. Return the root of the corresponding GCC tree.
2466 If this is an expression, return the GCC equivalent of the expression. If
2467 it is a statement, return the statement. In the case when called for a
2468 statement, it may also add statements to the current statement group, in
2469 which case anything it returns is to be interpreted as occurring after
2470 anything `it already added. */
2472 tree
2474 {
2478 tree gnu_expr;
2480 Node_Id gnat_temp;
2482 /* Save node number for error message and set location information. */
2490 /* If this node is a non-static subexpression and we are only
2491 annotating types, make this into a NULL_EXPR. */
2499 /* If this is a Statement and we are at top level, it must be part of
2500 the elaboration procedure, so mark us as being in that procedure
2501 and push our context. */
2513 {
2518 }
2521 {
2522 /********************************/
2523 /* Chapter 2: Lexical Elements: */
2524 /********************************/
2534 {
2535 tree gnu_type;
2537 /* Get the type of the result, looking inside any padding and
2538 justified modular types. Then get the value in that type. */
2547 /* If the result overflows (meaning it doesn't fit in its base type),
2548 abort. We would like to check that the value is within the range
2549 of the subtype, but that causes problems with subtypes whose usage
2550 will raise Constraint_Error and with biased representation, so
2551 we don't. */
2553 }
2557 /* If a Entity is present, it means that this was one of the
2558 literals in a user-defined character type. In that case,
2559 just return the value in the CONST_DECL. Otherwise, use the
2560 character code. In that case, the base type should be an
2561 INTEGER_TYPE, but we won't bother checking for that. */
2565 else
2566 gnu_result
2567 = force_fit_type
2568 (build_int_cst
2574 /* If this is of a fixed-point type, the value we want is the
2575 value of the corresponding integer. */
2577 {
2580 gnu_result_type);
2582 }
2584 /* We should never see a Vax_Float type literal, since the front end
2585 is supposed to transform these using appropriate conversions */
2589 else
2590 {
2595 /* If the real value is zero, so is the result. Otherwise,
2596 convert it to a machine number if it isn't already. That
2597 forces BASE to 0 or 2 and simplifies the rest of our logic. */
2600 else
2601 {
2603 ur_realval
2607 gnu_result
2610 /* If we have a base of zero, divide by the denominator.
2611 Otherwise, the base must be 2 and we scale the value, which
2612 we know can fit in the mantissa of the type (hence the use
2613 of that type above). */
2615 gnu_result
2618 gnu_result,
2620 gnu_result_type));
2621 else
2622 {
2623 REAL_VALUE_TYPE tmp;
2629 }
2630 }
2632 /* Now see if we need to negate the result. Do it this way to
2633 properly handle -0. */
2635 gnu_result
2637 gnu_result);
2638 }
2645 {
2651 /* Build the string with the characters in the literal. Note
2652 that Ada strings are 1-origin. */
2656 /* Put a null at the end of the string in case it's in a context
2657 where GCC will want to treat it as a C string. */
2662 /* Strings in GCC don't normally have types, but we want
2663 this to not be converted to the array type. */
2665 }
2666 else
2667 {
2668 /* Build a list consisting of each character, then make
2669 the aggregate. */
2677 {
2678 gnu_list
2683 gnu_list);
2687 }
2689 gnu_result
2691 }
2698 /**************************************/
2699 /* Chapter 3: Declarations and Types: */
2700 /**************************************/
2717 /* If we are just annotating types and this object has an unconstrained
2718 or task type, don't elaborate it. */
2729 && (!type_annotate_only
2731 {
2736 /* If this object has its elaboration delayed, we must force
2737 evaluation of GNU_EXPR right now and save it for when the object
2738 is frozen. */
2740 {
2743 gnu_expr
2748 else
2752 }
2753 }
2754 else
2767 /* Don't do anything if this renaming is handled by the front end or if
2768 we are just annotating types and this object has a composite or task
2769 type, don't elaborate it. We return the result in case it has any
2770 SAVE_EXPRs in it that need to be evaluated here. */
2772 && ! (type_annotate_only
2776 gnu_result
2779 else
2792 /* These are fully handled in the front end. */
2796 /*************************************/
2797 /* Chapter 4: Names and Expressions: */
2798 /*************************************/
2807 {
2809 tree gnu_type;
2817 /* If we got a padded type, remove it too. */
2820 gnu_array_object
2822 gnu_array_object);
2826 /* First compute the number of dimensions of the array, then
2827 fill the expression array, the order depending on whether
2828 this is a Convention_Fortran array or not. */
2833 ;
2842 else
2850 {
2856 gnu_expr
2857 = emit_index_check
2864 }
2865 }
2871 {
2872 tree gnu_type;
2878 /* Do any implicit dereferences of the prefix and do any needed
2879 range check. */
2884 {
2885 /* Get the bounds of the slice. */
2886 tree gnu_index_type
2892 /* Check to see that the minimum slice value is in range */
2893 gnu_expr_l
2894 = emit_index_check
2899 /* Check to see that the maximum slice value is in range */
2900 gnu_expr_h
2901 = emit_index_check
2906 /* Derive a good type to convert everything too */
2909 /* Build a compound expression that does the range checks */
2910 gnu_expr
2915 /* Build a conditional expression that returns the range checks
2916 expression if the slice range is not null (max >= min) or
2917 returns the min if the slice range is null */
2918 gnu_expr
2922 gnu_max_expr),
2924 gnu_min_expr)),
2926 }
2927 else
2932 }
2936 {
2940 tree gnu_field;
2944 {
2949 }
2953 /* For discriminant references in tagged types always substitute the
2954 corresponding discriminant as the actual selected component. */
2960 /* For discriminant references of untagged types always substitute the
2961 corresponding stored discriminant. */
2966 /* Handle extracting the real or imaginary part of a complex.
2967 The real part is the first field and the imaginary the last. */
2973 else
2974 {
2977 /* If there are discriminants, the prefix might be
2978 evaluated more than once, which is a problem if it has
2979 side-effects. */
2986 gnu_result
2990 }
2994 }
2998 {
2999 /* The attribute designator (like an enumeration value). */
3002 /* The Elab_Spec and Elab_Body attributes are special in that
3003 Prefix is a unit, not an object with a GCC equivalent. Similarly
3004 for Elaborated, since that variable isn't otherwise known. */
3008 attribute == Attr_Elab_Body
3011 gnat_node));
3014 }
3018 /* Like 'Access as far as we are concerned. */
3026 {
3027 tree gnu_aggr_type;
3029 /* ??? It is wrong to evaluate the type now, but there doesn't
3030 seem to be any other practical way of doing it. */
3034 gnu_aggr_type = gnu_result_type
3039 gnu_aggr_type
3047 {
3048 /* The first element is the discrimant, which we ignore. The
3049 next is the field we're building. Convert the expression
3050 to the type of the field and then to the union type. */
3051 Node_Id gnat_assoc
3054 tree gnu_field_type
3059 }
3062 gnu_result
3064 gnu_aggr_type);
3067 gnu_aggr_type,
3070 gnu_result
3071 = build_binary_op
3076 (Next
3078 else
3082 }
3092 /* Get the operand expression. */
3096 gnu_result
3108 /* If the result is a pointer type, see if we are improperly
3109 converting to a stricter alignment. */
3113 {
3119 post_error_ne_tree_2
3123 }
3131 {
3134 tree gnu_low;
3135 tree gnu_high;
3137 /* GNAT_RANGE is either an N_Range node or an identifier
3138 denoting a subtype. */
3140 {
3143 }
3146 {
3151 }
3152 else
3157 /* If LOW and HIGH are identical, perform an equality test.
3158 Otherwise, ensure that GNU_OBJECT is only evaluated once
3159 and perform a full range test. */
3163 else
3164 {
3166 gnu_result
3172 }
3176 }
3184 ? RDIV_EXPR
3191 /* These can either be operations on booleans or on modular types.
3192 Fall through for boolean types since that's the way GNU_CODES is
3193 set up. */
3195 Modular_Integer_Kind))
3196 {
3197 enum tree_code code
3208 }
3210 /* ... fall through ... */
3222 {
3224 tree gnu_type;
3230 /* If this is a comparison operator, convert any references to
3231 an unconstrained array value into a reference to the
3232 actual array. */
3234 {
3237 }
3239 /* If the result type is a private type, its full view may be a
3240 numeric subtype. The representation we need is that of its base
3241 type, given that it is the result of an arithmetic operation. */
3243 gnu_type = gnu_result_type
3246 /* If this is a shift whose count is not guaranteed to be correct,
3247 we need to adjust the shift count. */
3250 {
3252 tree gnu_max_shift
3260 gnu_rhs
3261 = build_binary_op
3264 gnu_count_type,
3265 gnu_max_shift,
3267 integer_one_node)),
3268 gnu_rhs);
3269 }
3271 /* For right shifts, the type says what kind of shift to do,
3272 so we may need to choose a different type. */
3281 {
3284 }
3288 /* If this is a logical shift with the shift count not verified,
3289 we must return zero if it is too large. We cannot compensate
3290 above in this case. */
3294 gnu_result
3295 = build_cond_expr
3298 gnu_rhs,
3302 gnu_result);
3303 }
3307 {
3310 tree gnu_false
3317 }
3326 /* This case can apply to a boolean or a modular type.
3327 Fall through for a boolean operand since GNU_CODES is set
3328 up to handle this. */
3330 {
3334 gnu_expr);
3336 }
3338 /* ... fall through ... */
3345 else
3354 {
3356 tree gnu_type;
3361 /* The Expression operand can either be an N_Identifier or
3362 Expanded_Name, which must represent a type, or a
3363 N_Qualified_Expression, which contains both the object type and an
3364 initial value for the object. */
3369 {
3370 Entity_Id gnat_desig_type
3382 {
3385 }
3386 else
3387 {
3393 }
3394 }
3395 else
3402 ignore_init_type);
3403 }
3406 /***************************/
3407 /* Chapter 5: Statements: */
3408 /***************************/
3420 /* Get the LHS and RHS of the statement and convert any reference to an
3421 unconstrained array into a reference to the underlying array.
3422 If we are not to do range checking and the RHS is an N_Function_Call,
3423 pass the LHS to the call function. */
3426 /* If the type has a size that overflows, convert this into raise of
3427 Storage_Error: execution shouldn't have gotten here anyway. */
3435 else
3436 {
3437 gnu_rhs
3440 /* If range check is needed, emit code to generate it */
3444 gnu_result
3446 }
3450 {
3453 /* Make the outer COND_EXPR. Avoid non-determinism. */
3462 /* Now make a COND_EXPR for each of the "else if" parts. Put each
3463 into the previous "else" part and point to where to put any
3464 outer "else". Also avoid non-determinism. */
3468 {
3478 }
3481 }
3505 gnu_result
3515 {
3516 /* The gnu function type of the subprogram currently processed. */
3518 /* The return value from the subprogram. */
3520 /* The place to put the return value. */
3521 tree gnu_lhs;
3522 /* Avoid passing error_mark_node to RETURN_EXPR. */
3525 /* If we are dealing with a "return;" from an Ada procedure with
3526 parameters passed by copy in copy out, we need to return a record
3527 containing the final values of these parameters. If the list
3528 contains only one entry, return just that entry.
3530 For a full description of the copy in copy out parameter mechanism,
3531 see the part of the gnat_to_gnu_entity routine dealing with the
3532 translation of subprograms.
3534 But if we have a return label defined, convert this into
3535 a branch to that label. */
3538 {
3542 }
3545 {
3549 else
3550 gnu_ret_val
3553 }
3555 /* If the Ada subprogram is a function, we just need to return the
3556 expression. If the subprogram returns an unconstrained
3557 array, we have to allocate a new version of the result and
3558 return it. If we return by reference, return a pointer. */
3561 {
3562 /* If the current function returns by target pointer and we
3563 are doing a call, pass that target to the call. */
3566 {
3567 gnu_lhs
3572 }
3573 else
3574 {
3578 /* The original return type was unconstrained so dereference
3579 the TARGET pointer in the actual return value's type. */
3580 gnu_lhs
3583 else
3586 /* Do not remove the padding from GNU_RET_VAL if the inner
3587 type is self-referential since we want to allocate the fixed
3588 size in that case. */
3592 && (TYPE_IS_PADDING_P
3594 && (CONTAINS_PLACEHOLDER_P
3600 gnu_ret_val
3604 {
3607 /* We have two cases: either the function returns with
3608 depressed stack or not. If not, we allocate on the
3609 secondary stack. If so, we allocate in the stack frame.
3610 if no copy is needed, the front end will set By_Ref,
3611 which we handle in the case above. */
3613 gnu_ret_val
3615 gnu_ret_val,
3618 else
3619 gnu_ret_val
3621 gnu_ret_val,
3626 }
3627 }
3628 }
3635 {
3638 }
3641 }
3649 /****************************/
3650 /* Chapter 6: Subprograms: */
3651 /****************************/
3654 /* Unless there is a freeze node, declare the subprogram. We consider
3655 this a "definition" even though we're not generating code for
3656 the subprogram because we will be making the corresponding GCC
3657 node here. */
3666 /* This subprogram doesn't exist for code generation purposes, but we
3667 have to elaborate the types of any parameters, unless they are
3668 imported types (nothing to generate in this case). */
3681 /* For a child unit identifier go up a level to get the
3682 specification. We get this when we try to find the spec of
3683 a child unit package that is the compilation unit being compiled. */
3697 /*************************/
3698 /* Chapter 7: Packages: */
3699 /*************************/
3715 /* If this is the body of a generic package - do nothing */
3717 {
3720 }
3731 /*********************************/
3732 /* Chapter 8: Visibility Rules: */
3733 /*********************************/
3737 /* Nothing to do here - but these may appear in list of declarations */
3741 /***********************/
3742 /* Chapter 9: Tasks: */
3743 /***********************/
3754 /***********************************************************/
3755 /* Chapter 10: Program Structure and Compilation Issues: */
3756 /***********************************************************/
3760 /* This is not called for the main unit, which is handled in function
3761 gigi above. */
3773 /* Simply process whatever unit is being inserted. */
3781 /***************************/
3782 /* Chapter 11: Exceptions: */
3783 /***************************/
3786 /* If there is an At_End procedure attached to this node, and the EH
3787 mechanism is SJLJ, we must have at least a corresponding At_End
3788 handler, unless the No_Exception_Handlers restriction is set. */
3803 else
3808 /*******************************/
3809 /* Chapter 12: Generic Units: */
3810 /*******************************/
3820 /* These nodes can appear on a declaration list but there is nothing to
3821 to be done with them. */
3825 /***************************************************/
3826 /* Chapter 13: Representation Clauses and */
3827 /* Implementation-Dependent Features: */
3828 /***************************************************/
3834 /* The only one we need deal with is for 'Address. For the others, SEM
3835 puts the information elsewhere. We need only deal with 'Address
3836 if the object has a Freeze_Node (which it never will currently). */
3841 /* Get the value to use as the address and save it as the
3842 equivalent for GNAT_TEMP. When the object is frozen,
3843 gnat_to_gnu_entity will do the right thing. */
3851 /* We do nothing with these. SEM puts the information elsewhere. */
3857 {
3863 /* First process inputs, then outputs, then clobbers. */
3866 {
3871 gnu_input_list
3874 }
3878 {
3883 gnu_output_list
3886 }
3890 gnu_clobber_list
3893 gnu_clobber_list);
3901 }
3902 else
3907 /***************************************************/
3908 /* Added Nodes */
3909 /***************************************************/
3927 {
3929 tree gnu_obj_type;
3930 tree gnu_obj_size;
3933 /* If this is a thin pointer, we must dereference it to create
3934 a fat pointer, then go back below to a thin pointer. The
3935 reason for this is that we need a fat pointer someplace in
3936 order to properly compute the size. */
3940 gnu_ptr));
3942 /* If this is an unconstrained array, we know the object must
3943 have been allocated with the template in front of the object.
3944 So pass the template address, but get the total size. Do this
3945 by converting to a thin pointer. */
3947 gnu_ptr
3949 (TYPE_OBJECT_RECORD_TYPE
3951 gnu_ptr);
3959 {
3962 tree gnu_byte_offset
3969 }
3974 gnat_node);
3975 }
3982 {
3985 }
3990 /* If the type is VOID, this is a statement, so we need to
3991 generate the code for the call. Handle a Condition, if there
3992 is one. */
3994 {
4001 }
4002 else
4007 /* If the result is a pointer type, see if we are either converting
4008 from a non-pointer or from a pointer to a type with a different
4009 alias set and warn if so. If the result defined in the same unit as
4010 this unchecked conversion, we can allow this because we can know to
4011 make that type have alias set 0. */
4012 {
4023 {
4024 post_error_ne
4027 post_error
4029 gnat_node);
4030 post_error_ne
4033 }
4035 /* The No_Strict_Aliasing flag is not propagated to the back-end for
4036 fat pointers so unconditionally warn in problematic cases. */
4038 {
4039 tree array_type
4046 {
4047 post_error_ne
4050 post_error
4052 gnat_node);
4053 }
4054 }
4055 }
4068 }
4070 /* If we pushed our level as part of processing the elaboration routine,
4071 pop it back now. */
4073 {
4078 }
4080 /* Set the location information into the result. Note that we may have
4081 no result if we tried to build a CALL_EXPR node to a procedure with
4082 no side-effects and optimization is enabled. */
4086 /* If we're supposed to return something of void_type, it means we have
4087 something we're elaborating for effect, so just return. */
4091 /* If the result is a constant that overflows, raise constraint error. */
4094 {
4097 gnu_result
4100 }
4102 /* If our result has side-effects and is of an unconstrained type,
4103 make a SAVE_EXPR so that we can be sure it will only be referenced
4104 once. Note we must do this before any conversions. */
4110 /* Now convert the result to the proper type. If the type is void or if
4111 we have no result, return error_mark_node to show we have no result.
4112 If the type of the result is correct or if we have a label (which doesn't
4113 have any well-defined type), return our result. Also don't do the
4114 conversion if the "desired" type involves a PLACEHOLDER_EXPR in its size
4115 since those are the cases where the front end may have the type wrong due
4116 to "instantiating" the unconstrained record with discriminant values
4117 or if this is a FIELD_DECL. If this is the Name of an assignment
4118 statement or a parameter of a procedure call, return what we have since
4119 the RHS has to be converted to our type there in that case, unless
4120 GNU_RESULT_TYPE has a simpler size. Similarly, if the two types are
4121 record types with the same name, the expression type has integral mode,
4122 and GNU_RESULT_TYPE BLKmode, don't convert. This will be the case when
4123 we are converting from a packable type to its actual type and we need
4124 those conversions to be NOPs in order for assignments into these types to
4125 work properly if the inner object is a bitfield and hence can't have
4126 its address taken. Finally, don't convert integral types that are the
4127 operand of an unchecked conversion since we need to ignore those
4128 conversions (for 'Valid). Otherwise, convert the result to the proper
4129 type. */
4149 && (CONTAINS_PLACEHOLDER_P
4153 {
4154 /* In this case remove padding only if the inner object is of
4155 self-referential size: in that case it must be an object of
4156 unconstrained type with a default discriminant. In other cases,
4157 we want to avoid copying too much data. */
4164 gnu_result);
4165 }
4181 {
4182 /* Remove any padding record, but do nothing more in this case. */
4186 gnu_result);
4187 }
4195 /* We don't need any NOP_EXPR or NON_LVALUE_EXPR on GNU_RESULT. */
4202 }
4203 \f
4204 /* Record the current code position in GNAT_NODE. */
4206 static void
4208 {
4213 }
4215 /* Insert the code for GNAT_NODE at the position saved for that node. */
4217 static void
4219 {
4222 }
4223 \f
4224 /* Start a new statement group chained to the previous group. */
4226 static void
4228 {
4231 /* First see if we can get one from the free list. */
4234 else
4240 }
4242 /* Add GNU_STMT to the current statement group. */
4244 void
4246 {
4249 /* If we're at top level, show everything in here is in use in case
4250 any of it is shared by a subprogram. */
4254 }
4256 /* Similar, but set the location of GNU_STMT to that of GNAT_NODE. */
4258 void
4260 {
4264 }
4266 /* Add a declaration statement for GNU_DECL to the current statement group.
4267 Get SLOC from Entity_Id. */
4269 void
4271 {
4272 tree gnu_stmt;
4274 /* If this is a variable that Gigi is to ignore, we may have been given
4275 an ERROR_MARK. So test for it. We also might have been given a
4276 reference for a renaming. So only do something for a decl. Also
4277 ignore a TYPE_DECL for an UNCONSTRAINED_ARRAY_TYPE. */
4283 /* If we are global, we don't want to actually output the DECL_EXPR for
4284 this decl since we already have evaluated the expressions in the
4285 sizes and positions as globals and doing it again would be wrong.
4286 But we do have to mark everything as used. */
4290 else
4291 {
4295 {
4299 }
4300 }
4302 /* If this is a DECL_EXPR for a variable with DECL_INITIAL set,
4303 there are two cases we need to handle here. */
4305 {
4309 /* If this is a DECL_EXPR for a variable with DECL_INITIAL set
4310 and decl has a padded type, convert it to the unpadded type so the
4311 assignment is done properly. */
4314 gnu_lhs
4317 /* Otherwise, if this is going into memory and the initializer isn't
4318 valid for the assembler and loader. Gimplification could do this,
4319 but would be run too late if -fno-unit-at-a-time. */
4326 {
4327 tree gnu_assign_stmt
4336 }
4337 }
4338 }
4340 /* Utility function to mark nodes with TREE_VISITED and types as having their
4341 sized gimplified. Called from walk_tree. We use this to indicate all
4342 variable sizes and positions in global types may not be shared by any
4343 subprogram. */
4345 static tree
4347 {
4351 /* Don't mark a dummy type as visited because we want to mark its sizes
4352 and fields once it's filled in. */
4360 }
4362 /* Likewise, but to mark as unvisited. */
4364 static tree
4367 {
4371 }
4373 /* Add GNU_CLEANUP, a cleanup action, to the current code group. */
4375 static void
4377 {
4379 }
4381 /* Set the BLOCK node corresponding to the current code group to GNU_BLOCK. */
4383 void
4385 {
4388 }
4390 /* Return code corresponding to the current code group. It is normally
4391 a STATEMENT_LIST, but may also be a BIND_EXPR or TRY_FINALLY_EXPR if
4392 BLOCK or cleanups were set. */
4394 static tree
4396 {
4400 /* If this is a null list, allocate a new STATEMENT_LIST. Then, if there
4401 are cleanups, make a TRY_FINALLY_EXPR. Last, if there is a BLOCK,
4402 make a BIND_EXPR. Note that we nest in that because the cleanup may
4403 reference variables in the block. */
4415 /* Remove this group from the stack and add it to the free list. */
4421 }
4423 /* Add a list of statements from GNAT_LIST, a possibly-empty list of
4424 statements.*/
4426 static void
4428 {
4429 Node_Id gnat_node;
4435 }
4437 /* Build a tree from GNAT_LIST, a possibly-empty list of statements.
4438 If BINDING_P is true, push and pop a binding level around the list. */
4440 static tree
4442 {
4452 }
4453 \f
4454 /* Push and pop routines for stacks. We keep a free list around so we
4455 don't waste tree nodes. */
4457 static void
4459 {
4463 {
4468 }
4469 else
4473 }
4475 static void
4477 {
4483 }
4484 \f
4485 /* GNU_STMT is a statement. We generate code for that statement. */
4487 void
4489 {
4490 #if 0
4492 #endif
4495 {
4496 #if 0
4498 /* First write a volatile ASM_INPUT to prevent anything from being
4499 moved. */
4505 modifier);
4508 #endif
4512 }
4513 }
4514 \f
4515 /* Generate GIMPLE in place for the expression at *EXPR_P. */
4517 int
4519 {
4526 {
4528 /* If this is for a scalar, just make a VAR_DECL for it. If for
4529 an aggregate, get a null pointer of the appropriate type and
4530 dereference it. */
4534 integer_zero_node));
4535 else
4536 {
4539 }
4545 /* We should only do this if we are just elaborating for side-effects,
4546 but we can't know that yet. */
4551 /* If we're taking the address of a constant CONSTRUCTOR, force it to
4552 be put into static memory. We know it's going to be readonly given
4553 the semantics we have and it's required to be static memory in
4554 the case when the reference is in an elaboration procedure. */
4557 {
4558 tree new_var
4569 }
4573 /* We have a kludge here. If the FIELD_DECL is from a fat pointer and is
4574 from an early dummy type, replace it with the proper FIELD_DECL. */
4577 {
4581 }
4583 /* ... fall through ... */
4587 }
4588 }
4590 /* Generate GIMPLE in place for the statement at *STMT_P. */
4592 static enum gimplify_status
4594 {
4598 {
4608 {
4612 /* Set to emit the statements of the loop. */
4615 /* We first emit the start label and then a conditional jump to
4616 the end label if there's a top condition, then the body of the
4617 loop, then a conditional branch to the end label, then the update,
4618 if any, and finally a jump to the start label and the definition
4619 of the end label. */
4621 gnu_start_label),
4622 stmt_p);
4629 void_type_node,
4630 gnu_end_label)),
4631 stmt_p);
4640 void_type_node,
4641 gnu_end_label)),
4642 stmt_p);
4648 gnu_start_label),
4649 stmt_p);
4651 gnu_end_label),
4652 stmt_p);
4654 }
4657 /* Build a statement to jump to the corresponding end label, then
4658 see if it needs to be conditional. */
4667 }
4668 }
4669 \f
4670 /* Force references to each of the entities in packages GNAT_NODE with's
4671 so that the debugging information for all of them are identical
4672 in all clients. Operate recursively on anything it with's, but check
4673 that we aren't elaborating something more than once. */
4675 /* The reason for this routine's existence is two-fold.
4676 First, with some debugging formats, notably MDEBUG on SGI
4677 IRIX, the linker will remove duplicate debugging information if two
4678 clients have identical debugguing information. With the normal scheme
4679 of elaboration, this does not usually occur, since entities in with'ed
4680 packages are elaborated on demand, and if clients have different usage
4681 patterns, the normal case, then the order and selection of entities
4682 will differ. In most cases however, it seems that linkers do not know
4683 how to eliminate duplicate debugging information, even if it is
4684 identical, so the use of this routine would increase the total amount
4685 of debugging information in the final executable.
4687 Second, this routine is called in type_annotate mode, to compute DDA
4688 information for types in withed units, for ASIS use */
4690 static void
4692 {
4695 /* Process each unit only once. As we trace the context of all relevant
4696 units transitively, including generic bodies, we may encounter the
4697 same generic unit repeatedly */
4702 /* Save entities in all context units. A body may have an implicit_with
4703 on its own spec, if the context includes a child unit, so don't save
4704 the spec twice. */
4712 {
4716 {
4733 }
4735 {
4736 Node_Id gnat_body
4739 /* Retrieve compilation unit node of generic body. */
4744 /* If body is available, elaborate its context. */
4747 }
4748 }
4752 }
4753 \f
4754 /* Do the processing of N_Freeze_Entity, GNAT_NODE. */
4756 static void
4758 {
4760 tree gnu_old;
4761 tree gnu_new;
4762 tree gnu_init
4767 /* If this is a package, need to generate code for the package. */
4769 {
4770 insert_code_for
4774 }
4776 /* Check for old definition after the above call. This Freeze_Node
4777 might be for one its Itypes. */
4778 gnu_old
4781 /* If this entity has an Address representation clause, GNU_OLD is the
4782 address, so discard it here. */
4786 /* Don't do anything for class-wide types they are always
4787 transformed into their root type. */
4793 /* Don't do anything for subprograms that may have been elaborated before
4794 their freeze nodes. This can happen, for example because of an inner call
4795 in an instance body, or a previous compilation of a spec for inlining
4796 purposes. */
4801 || (gnu_old
4806 /* If we have a non-dummy type old tree, we have nothing to do. Unless
4807 this is the public view of a private type whose full view was not
4808 delayed, this node was never delayed as it should have been.
4809 Also allow this to happen for concurrent types since we may have
4810 frozen both the Corresponding_Record_Type and this type. */
4814 {
4820 }
4822 /* Reset the saved tree, if any, and elaborate the object or type for real.
4823 If there is a full declaration, elaborate it and copy the type to
4824 GNAT_ENTITY. Likewise if this is the record subtype corresponding to
4825 a class wide type or subtype. */
4827 {
4836 }
4840 {
4843 /* Propagate back-annotations from full view to partial view. */
4853 /* The above call may have defined this entity (the simplest example
4854 of this is when we have a private enumeral type since the bounds
4855 will have the public view. */
4861 }
4862 else
4865 /* If we've made any pointers to the old version of this type, we
4866 have to update them. */
4870 }
4871 \f
4872 /* Process the list of inlined subprograms of GNAT_NODE, which is an
4873 N_Compilation_Unit. */
4875 static void
4877 {
4878 Entity_Id gnat_entity;
4879 Node_Id gnat_body;
4881 /* If we can inline, generate RTL for all the inlined subprograms.
4882 Define the entity first so we set DECL_EXTERNAL. */
4887 {
4891 {
4892 /* ??? This really should always be Present. */
4896 gnat_body
4898 }
4901 {
4904 }
4905 }
4906 }
4907 \f
4908 /* Elaborate decls in the lists GNAT_DECLS and GNAT_DECLS2, if present.
4909 We make two passes, one to elaborate anything other than bodies (but
4910 we declare a function if there was no spec). The second pass
4911 elaborates the bodies.
4913 GNAT_END_LIST gives the element in the list past the end. Normally,
4914 this is Empty, but can be First_Real_Statement for a
4915 Handled_Sequence_Of_Statements.
4917 We make a complete pass through both lists if PASS1P is true, then make
4918 the second pass over both lists if PASS2P is true. The lists usually
4919 correspond to the public and private parts of a package. */
4921 static void
4924 {
4926 Node_Id gnat_decl;
4936 {
4937 /* For package specs, we recurse inside the declarations,
4938 thus taking the two pass approach inside the boundary. */
4946 /* Similarly for any declarations in the actions of a
4947 freeze node. */
4949 {
4952 }
4954 /* Package bodies with freeze nodes get their elaboration deferred
4955 until the freeze node, but the code must be placed in the right
4956 place, so record the code position now. */
4964 (Corresponding_Spec
4967 record_code_position
4970 /* We defer most subprogram bodies to the second pass. */
4972 {
4974 {
4980 }
4981 }
4982 /* For bodies and stubs that act as their own specs, the entity
4983 itself must be elaborated in the first pass, because it may
4984 be used in other declarations. */
4986 {
4987 Node_Id gnat_subprog_id =
4994 }
4996 /* Concurrent stubs stand for the corresponding subprogram bodies,
4997 which are deferred like other bodies. */
5000 ;
5001 else
5003 }
5005 /* Here we elaborate everything we deferred above except for package bodies,
5006 which are elaborated at their freeze nodes. Note that we must also
5007 go inside things (package specs and freeze nodes) the first pass did. */
5013 {
5029 }
5030 }
5031 \f
5032 /* Emit code for a range check. GNU_EXPR is the expression to be checked,
5033 GNAT_RANGE_TYPE the gnat type or subtype containing the bounds against
5034 which we have to check. */
5036 static tree
5038 {
5044 /* If GNU_EXPR has an integral type that is narrower than GNU_RANGE_TYPE,
5045 we can't do anything since we might be truncating the bounds. No
5046 check is needed in this case. */
5052 /* Checked expressions must be evaluated only once. */
5055 /* There's no good type to use here, so we might as well use
5056 integer_type_node. Note that the form of the check is
5057 (not (expr >= lo)) or (not (expr >= hi))
5058 the reason for this slightly convoluted form is that NaN's
5059 are not considered to be in range in the float case. */
5060 return emit_check
5062 invert_truthvalue
5066 invert_truthvalue
5070 gnu_high)))),
5072 }
5073 \f
5074 /* Emit code for an index check. GNU_ARRAY_OBJECT is the array object
5075 which we are about to index, GNU_EXPR is the index expression to be
5076 checked, GNU_LOW and GNU_HIGH are the lower and upper bounds
5077 against which GNU_EXPR has to be checked. Note that for index
5078 checking we cannot use the emit_range_check function (although very
5079 similar code needs to be generated in both cases) since for index
5080 checking the array type against which we are checking the indeces
5081 may be unconstrained and consequently we need to retrieve the
5082 actual index bounds from the array object itself
5083 (GNU_ARRAY_OBJECT). The place where we need to do that is in
5084 subprograms having unconstrained array formal parameters */
5086 static tree
5088 tree gnu_expr,
5089 tree gnu_low,
5090 tree gnu_high)
5091 {
5092 tree gnu_expr_check;
5094 /* Checked expressions must be evaluated only once. */
5097 /* Must do this computation in the base type in case the expression's
5098 type is an unsigned subtypes. */
5101 /* If GNU_LOW or GNU_HIGH are a PLACEHOLDER_EXPR, qualify them by
5102 the object we are handling. */
5106 /* There's no good type to use here, so we might as well use
5107 integer_type_node. */
5108 return emit_check
5111 gnu_expr_check,
5113 gnu_low)),
5115 gnu_expr_check,
5117 gnu_high))),
5119 }
5120 \f
5121 /* GNU_COND contains the condition corresponding to an access, discriminant or
5122 range check of value GNU_EXPR. Build a COND_EXPR that returns GNU_EXPR if
5123 GNU_COND is false and raises a CONSTRAINT_ERROR if GNU_COND is true.
5124 REASON is the code that says why the exception was raised. */
5126 static tree
5128 {
5129 tree gnu_call;
5130 tree gnu_result;
5134 /* Use an outer COMPOUND_EXPR to make sure that GNU_EXPR will get evaluated
5135 in front of the comparison in case it ends up being a SAVE_EXPR. Put the
5136 whole thing inside its own SAVE_EXPR so the inner SAVE_EXPR doesn't leak
5137 out. */
5141 gnu_expr));
5143 /* If GNU_EXPR has side effects, make the outer COMPOUND_EXPR and
5144 protect it. Otherwise, show GNU_RESULT has no side effects: we
5145 don't need to evaluate it just for the check. */
5147 gnu_result
5149 else
5152 /* ??? Unfortunately, if we don't put a SAVE_EXPR around this whole thing,
5153 we will repeatedly do the test. It would be nice if GCC was able
5154 to optimize this and only do it once. */
5156 }
5157 \f
5158 /* Return an expression that converts GNU_EXPR to GNAT_TYPE, doing
5159 overflow checks if OVERFLOW_P is nonzero and range checks if
5160 RANGE_P is nonzero. GNAT_TYPE is known to be an integral type.
5161 If TRUNCATE_P is nonzero, do a float to integer conversion with
5162 truncation; otherwise round. */
5164 static tree
5167 {
5175 /* If we are not doing any checks, the output is an integral type, and
5176 the input is not a floating type, just do the conversion. This
5177 shortcut is required to avoid problems with packed array types
5178 and simplifies code in all cases anyway. */
5183 /* First convert the expression to its base type. This
5184 will never generate code, but makes the tests below much simpler.
5185 But don't do this if converting from an integer type to an unconstrained
5186 array type since then we need to get the bounds from the original
5187 (unpacked) type. */
5191 /* If overflow checks are requested, we need to be sure the result will
5192 fit in the output base type. But don't do this if the input
5193 is integer and the output floating-point. */
5196 {
5197 /* Ensure GNU_EXPR only gets evaluated once. */
5205 /* Convert the lower bounds to signed types, so we're sure we're
5206 comparing them properly. Likewise, convert the upper bounds
5207 to unsigned types. */
5221 /* Check each bound separately and only if the result bound
5222 is tighter than the bound on the input type. Note that all the
5223 types are base types, so the bounds must be constant. Also,
5224 the comparison is done in the base type of the input, which
5225 always has the proper signedness. First check for input
5226 integer (which means output integer), output float (which means
5227 both float), or mixed, in which case we always compare.
5228 Note that we have to do the comparison which would *fail* in the
5229 case of an error since if it's an FP comparison and one of the
5230 values is a NaN or Inf, the comparison will fail. */
5237 gnu_cond
5238 = invert_truthvalue
5241 gnu_out_lb)));
5249 gnu_cond
5251 invert_truthvalue
5253 gnu_input,
5255 gnu_out_ub))));
5259 CE_Overflow_Check_Failed);
5260 }
5262 /* Now convert to the result base type. If this is a non-truncating
5263 float-to-integer conversion, round. */
5266 {
5272 /* The following calculations depend on proper rounding to even
5273 of each arithmetic operation. In order to prevent excess
5274 precision from spoiling this property, use the widest hardware
5275 floating-point type.
5277 FIXME: For maximum efficiency, this should only be done for machines
5278 and types where intermediates may have extra precision. */
5281 /* FIXME: Should not have padding in the first place */
5286 /* Compute the exact value calc_type'Pred (0.5) at compile time. */
5290 half_minus_pred_half);
5293 /* If the input is strictly negative, subtract this value
5294 and otherwise add it from the input. For 0.5, the result
5295 is exactly between 1.0 and the machine number preceding 1.0
5296 (for calc_type). Since the last bit of 1.0 is even, this 0.5
5297 will round to 1.0, while all other number with an absolute
5298 value less than 0.5 round to 0.0. For larger numbers exactly
5299 halfway between integers, rounding will always be correct as
5300 the true mathematical result will be closer to the higher
5301 integer compared to the lower one. So, this constant works
5302 for all floating-point numbers.
5304 The reason to use the same constant with subtract/add instead
5305 of a positive and negative constant is to allow the comparison
5306 to be scheduled in parallel with retrieval of the constant and
5307 conversion of the input to the calc_type (if necessary).
5308 */
5315 gnu_add_pred_half
5317 gnu_subtract_pred_half
5321 }
5327 else
5330 /* Finally, do the range check if requested. Note that if the
5331 result type is a modular type, the range check is actually
5332 an overflow check. */
5340 }
5341 \f
5342 /* Return 1 if GNU_EXPR can be directly addressed. This is the case unless
5343 it is an expression involving computation or if it involves a reference
5344 to a bitfield or to a field not sufficiently aligned for its type. */
5346 static bool
5348 {
5350 {
5355 /* All DECLs are addressable: if they are in a register, we can force
5356 them to memory. */
5368 && (!STRICT_ALIGNMENT
5369 /* If the field was marked as "semantically" addressable
5370 in create_field_decl, we are guaranteed that it can
5371 be directly addressed. */
5373 /* Otherwise it can nevertheless be directly addressed
5374 if it has been sufficiently aligned in the record. */
5389 {
5390 /* This is addressable if we can avoid a copy. */
5404 }
5408 }
5409 }
5410 \f
5411 /* Do the processing for the declaration of a GNAT_ENTITY, a type. If
5412 a separate Freeze node exists, delay the bulk of the processing. Otherwise
5413 make a GCC type for GNAT_ENTITY and set up the correspondence. */
5415 void
5417 {
5418 tree gnu_old
5420 tree gnu_new;
5422 /* If we are to delay elaboration of this type, just do any
5423 elaborations needed for expressions within the declaration and
5424 make a dummy type entry for this node and its Full_View (if
5425 any) in case something points to it. Don't do this if it
5426 has already been done (the only way that can happen is if
5427 the private completion is also delayed). */
5433 {
5437 {
5446 }
5449 }
5451 /* If we saved away a dummy type for this node it means that this
5452 made the type that corresponds to the full type of an incomplete
5453 type. Clear that type for now and then update the type in the
5454 pointers. */
5456 {
5459 {
5460 /* If this was a withed access type, this is not an error
5461 and merely indicates we've already elaborated the type
5462 already. */
5465 }
5468 }
5470 /* Now fully elaborate the type. */
5474 /* If we have an old type and we've made pointers to this type,
5475 update those pointers. */
5480 /* If this is a record type corresponding to a task or protected type
5481 that is a completion of an incomplete type, perform a similar update
5482 on the type. */
5483 /* ??? Including protected types here is a guess. */
5488 {
5489 tree gnu_task_old
5499 }
5500 }
5501 \f
5502 /* GNAT_ASSOC is the front of the Component_Associations of an N_Aggregate.
5503 GNU_TYPE is the GCC type of the corresponding record.
5505 Return a CONSTRUCTOR to build the record. */
5507 static tree
5509 {
5512 /* We test for GNU_FIELD being empty in the case where a variant
5513 was the last thing since we don't take things off GNAT_ASSOC in
5514 that case. We check GNAT_ASSOC in case we have a variant, but it
5515 has no fields. */
5519 {
5524 /* The expander is supposed to put a single component selector name
5525 in every record component association */
5528 /* Ignore fields that have Corresponding_Discriminants since we'll
5529 be setting that field in the parent. */
5534 /* Before assigning a value in an aggregate make sure range checks
5535 are done if required. Then convert to the type of the field. */
5541 /* Add the field and expression to the list. */
5543 }
5547 #ifdef ENABLE_CHECKING
5548 {
5549 tree gnu_field;
5551 /* Verify every enty in GNU_LIST was used. */
5554 }
5555 #endif
5558 }
5560 /* Builds a possibly nested constructor for array aggregates. GNAT_EXPR
5561 is the first element of an array aggregate. It may itself be an
5562 aggregate (an array or record aggregate). GNU_ARRAY_TYPE is the gnu type
5563 corresponding to the array aggregate. GNAT_COMPONENT_TYPE is the type
5564 of the array component. It is needed for range checking. */
5566 static tree
5568 Entity_Id gnat_component_type)
5569 {
5572 tree gnu_expr;
5575 {
5576 /* If the expression is itself an array aggregate then first build the
5577 innermost constructor if it is part of our array (multi-dimensional
5578 case). */
5585 gnat_component_type);
5586 else
5587 {
5590 /* before assigning the element to the array make sure it is
5591 in range */
5594 }
5596 gnu_expr_list
5598 gnu_expr_list);
5601 }
5604 }
5605 \f
5606 /* Subroutine of assoc_to_constructor: VALUES is a list of field associations,
5607 some of which are from RECORD_TYPE. Return a CONSTRUCTOR consisting
5608 of the associations that are from RECORD_TYPE. If we see an internal
5609 record, make a recursive call to fill it in as well. */
5611 static tree
5613 {
5618 {
5621 /* _Parent is an internal field, but may have values in the aggregate,
5622 so check for values first. */
5624 {
5627 }
5630 {
5635 }
5636 else
5637 /* If we have a record subtype, the names will match, but not the
5638 actual FIELD_DECLs. */
5641 {
5644 }
5650 }
5653 }
5654 \f
5655 /* EXP is to be treated as an array or record. Handle the cases when it is
5656 an access object and perform the required dereferences. */
5658 static tree
5660 {
5661 /* If the type is a pointer, dereference it. */
5666 /* If we got a padded type, remove it too. */
5672 }
5673 \f
5674 /* Protect EXP from multiple evaluation. This may make a SAVE_EXPR. */
5676 tree
5678 {
5681 /* If this has no side effects, we don't need to do anything. */
5685 /* If it is a conversion, protect what's inside the conversion.
5686 Similarly, if we're indirectly referencing something, we only
5687 actually need to protect the address since the data itself can't
5688 change in these situations. */
5697 /* If EXP is a fat pointer or something that can be placed into a register,
5698 just make a SAVE_EXPR. */
5702 /* Otherwise, dereference, protect the address, and re-reference. */
5703 else
5704 return
5708 exp)));
5709 }
5710 \f
5711 /* This is equivalent to stabilize_reference in GCC's tree.c, but we know
5712 how to handle our new nodes and we take an extra argument that says
5713 whether to force evaluation of everything. */
5715 tree
5717 {
5720 tree result;
5723 {
5727 /* No action is needed in this case. */
5739 result
5748 force));
5754 force),
5762 force),
5764 force));
5772 force),
5779 force),
5781 force));
5784 /* If arg isn't a kind of lvalue we recognize, make no change.
5785 Caller should recognize the error for an invalid lvalue. */
5791 }
5795 /* TREE_THIS_VOLATILE and TREE_SIDE_EFFECTS attached to the initial
5796 expression may not be sustained across some paths, such as the way via
5797 build1 for INDIRECT_REF. We re-populate those flags here for the general
5798 case, which is consistent with the GCC version of this routine.
5800 Special care should be taken regarding TREE_SIDE_EFFECTS, because some
5801 paths introduce side effects where there was none initially (e.g. calls
5802 to save_expr), and we also want to keep track of that. */
5808 }
5810 /* Similar to stabilize_reference_1 in tree.c, but supports an extra
5811 arg to force a SAVE_EXPR for everything. */
5813 static tree
5815 {
5818 tree result;
5820 /* We cannot ignore const expressions because it might be a reference
5821 to a const array but whose index contains side-effects. But we can
5822 ignore things that are actual constant or that already have been
5823 handled by this function. */
5829 {
5837 /* If this is a COMPONENT_REF of a fat pointer, save the entire
5838 fat pointer. This may be more efficient, but will also allow
5839 us to more easily find the match for the PLACEHOLDER_EXPR. */
5844 force),
5848 else
5853 /* Constants need no processing. In fact, we should never reach
5854 here. */
5858 /* Recursively stabilize each operand. */
5862 force));
5866 /* Recursively stabilize each operand. */
5869 force));
5874 }
5881 }
5883 /* Build a global constructor or destructor function. METHOD_TYPE gives
5884 the type of the function and CDTORS points to the list of constructor
5885 or destructor functions to be invoked. FIXME: Migrate into cgraph. */
5887 static void
5889 {
5893 {
5898 NULL_TREE);
5900 }
5903 }
5904 \f
5907 /* Convert Sloc into *LOCUS (a location_t). Return true if this Sloc
5908 corresponds to a source code location and false if it doesn't. In the
5909 latter case, we don't update *LOCUS. We also set the Gigi global variable
5910 REF_FILENAME to the reference file name as given by sinput (i.e no
5911 directory). */
5913 bool
5915 {
5916 /* If node not from source code, ignore. */
5920 /* Use the identifier table to make a hashed, permanent copy of the filename,
5921 since the name table gets reallocated after Gigi returns but before all
5922 the debugging information is output. The __gnat_to_canonical_file_spec
5923 call translates filenames from pragmas Source_Reference that contain host
5924 style syntax not understood by gdb. */
5925 locus->file
5926 = IDENTIFIER_POINTER
5927 (get_identifier
5928 (__gnat_to_canonical_file_spec
5933 ref_filename
5934 = IDENTIFIER_POINTER
5935 (get_identifier
5939 }
5941 /* Similar to annotate_with_locus, but start with the Sloc of GNAT_NODE and
5942 don't do anything if it doesn't correspond to a source location. */
5944 static void
5946 {
5947 location_t locus;
5953 }
5954 \f
5955 /* Post an error message. MSG is the error message, properly annotated.
5956 NODE is the node at which to post the error and the node to use for the
5957 "&" substitution. */
5959 void
5961 {
5962 String_Template temp;
5963 Fat_Pointer fp;
5969 }
5971 /* Similar, but NODE is the node at which to post the error and ENT
5972 is the node to use for the "&" substitution. */
5974 void
5976 {
5977 String_Template temp;
5978 Fat_Pointer fp;
5984 }
5986 /* Similar, but NODE is the node at which to post the error, ENT is the node
5987 to use for the "&" substitution, and N is the number to use for the ^. */
5989 void
5991 {
5992 String_Template temp;
5993 Fat_Pointer fp;
6001 }
6002 \f
6003 /* Similar to post_error_ne_num, but T is a GCC tree representing the
6004 number to write. If the tree represents a constant that fits within
6005 a host integer, the text inside curly brackets in MSG will be output
6006 (presumably including a '^'). Otherwise that text will not be output
6007 and the text inside square brackets will be output instead. */
6009 void
6011 {
6014 Fat_Pointer fp;
6022 #if HOST_BITS_PER_WIDE_INT > HOST_BITS_PER_INT
6023 &&
6024 compare_tree_int
6026 #endif
6027 )
6028 {
6031 }
6032 else
6036 {
6042 ;
6043 else
6045 }
6052 }
6054 /* Similar to post_error_ne_tree, except that NUM is a second
6055 integer to write in the message. */
6057 void
6059 Node_Id node,
6060 Entity_Id ent,
6061 tree t,
6063 {
6066 }
6067 \f
6068 /* Initialize the table that maps GNAT codes to GCC codes for simple
6069 binary and unary operations. */
6071 void
6073 {
6099 }