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Diffstat (limited to 'gcc/cp/expr.c')
| -rwxr-xr-x | gcc/cp/expr.c | 433 |
1 files changed, 433 insertions, 0 deletions
diff --git a/gcc/cp/expr.c b/gcc/cp/expr.c new file mode 100755 index 0000000..3dc8eae --- /dev/null +++ b/gcc/cp/expr.c @@ -0,0 +1,433 @@ +/* Convert language-specific tree expression to rtl instructions, + for GNU compiler. + Copyright (C) 1988, 92-97, 1998 Free Software Foundation, Inc. + +This file is part of GNU CC. + +GNU CC is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2, or (at your option) +any later version. + +GNU CC is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +You should have received a copy of the GNU General Public License +along with GNU CC; see the file COPYING. If not, write to +the Free Software Foundation, 59 Temple Place - Suite 330, +Boston, MA 02111-1307, USA. */ + + +#include "config.h" +#include "system.h" +#include "rtl.h" +#include "tree.h" +#include "flags.h" +#include "expr.h" +#include "cp-tree.h" +#include "toplev.h" + +#if 0 +static tree extract_aggr_init PROTO((tree, tree)); +static tree extract_scalar_init PROTO((tree, tree)); +#endif +static rtx cplus_expand_expr PROTO((tree, rtx, enum machine_mode, + enum expand_modifier)); + +/* Hook used by expand_expr to expand language-specific tree codes. */ + +static rtx +cplus_expand_expr (exp, target, tmode, modifier) + tree exp; + rtx target; + enum machine_mode tmode; + enum expand_modifier modifier; +{ + tree type = TREE_TYPE (exp); + register enum machine_mode mode = TYPE_MODE (type); + register enum tree_code code = TREE_CODE (exp); + int ignore = target == const0_rtx; + + if (ignore) + target = 0; + + /* No sense saving up arithmetic to be done + if it's all in the wrong mode to form part of an address. + And force_operand won't know whether to sign-extend or zero-extend. */ + + if (mode != Pmode && modifier == EXPAND_SUM) + modifier = EXPAND_NORMAL; + + switch (code) + { + case AGGR_INIT_EXPR: + { + /* Something needs to be initialized, but we didn't know + where that thing was when building the tree. For example, + it could be the return value of a function, or a parameter + to a function which lays down in the stack, or a temporary + variable which must be passed by reference. + + Cleanups are handled in a language-specific way: they + might be run by the called function (true in GNU C++ + for parameters with cleanups), or they might be + run by the caller, after the call (true in GNU C++ + for other cleanup needs). */ + + tree func = TREE_OPERAND (exp, 0); + tree args = TREE_OPERAND (exp, 1); + tree type = TREE_TYPE (exp), slot; + tree call_exp; + rtx call_target, return_target; + int pcc_struct_return = 0; + + /* The expression `init' wants to initialize what + `target' represents. SLOT holds the slot for TARGET. */ + slot = TREE_OPERAND (exp, 2); + + /* Should always be called with a target. */ + my_friendly_assert (target != NULL_RTX, 205); + + /* The target the initializer will initialize (CALL_TARGET) + must now be directed to initialize the target we are + supposed to initialize (TARGET). The semantics for + choosing what CALL_TARGET is is language-specific, + as is building the call which will perform the + initialization. It is left here to show the choices that + exist for C++. */ + + if (TREE_CODE (func) == ADDR_EXPR + && TREE_CODE (TREE_OPERAND (func, 0)) == FUNCTION_DECL + && DECL_CONSTRUCTOR_P (TREE_OPERAND (func, 0))) + { + type = build_pointer_type (type); + /* Don't clobber a value that might be part of a default + parameter value. */ + mark_addressable (slot); + if (TREE_PERMANENT (args)) + args = expr_tree_cons (0, build1 (ADDR_EXPR, type, slot), + TREE_CHAIN (args)); + else + TREE_VALUE (args) = build1 (ADDR_EXPR, type, slot); + call_target = 0; + } + else + { + call_target = target; +#ifdef PCC_STATIC_STRUCT_RETURN + if (aggregate_value_p (type)) + { + pcc_struct_return = 1; + call_target = 0; + } +#endif + } + + call_exp = build (CALL_EXPR, type, func, args, NULL_TREE); + TREE_SIDE_EFFECTS (call_exp) = 1; + return_target = expand_call (call_exp, call_target, ignore); + + if (call_target) + /* Trust that the right thing has been done; it's too hard to + verify. */ + return return_target; + + /* If we're suffering under the ancient PCC_STATIC_STRUCT_RETURN + calling convention, we need to copy the return value out of + the static return buffer into slot. */ + if (pcc_struct_return) + { + extern int flag_access_control; + int old_ac = flag_access_control; + + tree init = build_decl (VAR_DECL, NULL_TREE, + build_reference_type (type)); + DECL_RTL (init) = XEXP (return_target, 0); + init = convert_from_reference (init); + + flag_access_control = 0; + expand_aggr_init (slot, init, LOOKUP_ONLYCONVERTING); + flag_access_control = old_ac; + + if (TYPE_NEEDS_DESTRUCTOR (type)) + { + init = maybe_build_cleanup (init); + if (init != NULL_TREE) + expand_expr (init, const0_rtx, VOIDmode, 0); + } + } + + return DECL_RTL (slot); + } + + case PTRMEM_CST: + { + tree member; + tree offset; + + /* Find the member. */ + member = PTRMEM_CST_MEMBER (exp); + + if (TREE_CODE (member) == FIELD_DECL) + { + /* Find the offset for the field. */ + offset = convert (sizetype, + size_binop (EASY_DIV_EXPR, + DECL_FIELD_BITPOS (member), + size_int (BITS_PER_UNIT))); + + /* We offset all pointer to data members by 1 so that we + can distinguish between a null pointer to data member + and the first data member of a structure. */ + offset = size_binop (PLUS_EXPR, offset, size_int (1)); + + return expand_expr (cp_convert (type, offset), target, tmode, + modifier); + } + else + { + /* We don't yet handle pointer-to-member functions this + way. */ + my_friendly_abort (0); + return 0; + } + } + + case OFFSET_REF: + { + return expand_expr (default_conversion (resolve_offset_ref (exp)), + target, tmode, EXPAND_NORMAL); + } + + case THUNK_DECL: + return DECL_RTL (exp); + + case THROW_EXPR: + expand_throw (TREE_OPERAND (exp, 0)); + return NULL; + + case VEC_INIT_EXPR: + return expand_expr + (expand_vec_init + (NULL_TREE, TREE_OPERAND (exp, 0), + build_binary_op (MINUS_EXPR, TREE_OPERAND (exp, 2), + integer_one_node, 1), + TREE_OPERAND (exp, 1), 0), target, tmode, modifier); + + case NEW_EXPR: + return expand_expr (build_new_1 (exp), target, tmode, modifier); + + default: + break; + } + my_friendly_abort (40); + /* NOTREACHED */ + return NULL; +} + +void +init_cplus_expand () +{ + lang_expand_expr = cplus_expand_expr; +} + +/* If DECL had its rtl moved from where callers expect it + to be, fix it up. RESULT is the nominal rtl for the RESULT_DECL, + which may be a pseudo instead of a hard register. */ + +void +fixup_result_decl (decl, result) + tree decl; + rtx result; +{ + if (REG_P (result)) + { + if (REGNO (result) >= FIRST_PSEUDO_REGISTER) + { + rtx real_decl_result; + +#ifdef FUNCTION_OUTGOING_VALUE + real_decl_result + = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl), current_function_decl); +#else + real_decl_result + = FUNCTION_VALUE (TREE_TYPE (decl), current_function_decl); +#endif + REG_FUNCTION_VALUE_P (real_decl_result) = 1; + result = real_decl_result; + } + store_expr (decl, result, 0); + emit_insn (gen_rtx (USE, VOIDmode, result)); + } +} + +#if 0 +/* Expand this initialization inline and see if it's simple enough that + it can be done at compile-time. */ + +static tree +extract_aggr_init (decl, init) + tree decl, init; +{ + return 0; +} + +static tree +extract_scalar_init (decl, init) + tree decl, init; +{ + rtx value, insns, insn; + extern struct obstack temporary_obstack; + tree t = NULL_TREE; + + push_obstacks (&temporary_obstack, &temporary_obstack); + start_sequence (); + value = expand_expr (init, NULL_RTX, VOIDmode, 0); + insns = get_insns (); + end_sequence (); + reg_scan (insns, max_reg_num (), 0); + jump_optimize (insns, 0, 0, 1); + pop_obstacks (); + + for (insn = insns; insn; insn = NEXT_INSN (insn)) + { + rtx r, to; + + if (GET_CODE (insn) == NOTE) + continue; + else if (GET_CODE (insn) != INSN) + return 0; + + r = PATTERN (insn); + if (GET_CODE (r) != SET) + return 0; + + to = XEXP (r, 0); + + if (! (to == value + || (GET_CODE (to) == SUBREG && XEXP (to, 0) == value))) + return 0; + + r = XEXP (r, 1); + + switch (GET_CODE (r)) + { + case CONST_INT: + t = build_int_2 (XEXP (r, 0), 0); + break; + default: + return 0; + } + } + + return t; +} +#endif + +int +extract_init (decl, init) + tree decl ATTRIBUTE_UNUSED, init ATTRIBUTE_UNUSED; +{ + return 0; + +#if 0 + if (IS_AGGR_TYPE (TREE_TYPE (decl)) + || TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE) + init = extract_aggr_init (decl, init); + else + init = extract_scalar_init (decl, init); + + if (init == NULL_TREE) + return 0; + + DECL_INITIAL (decl) = init; + return 1; +#endif +} + +void +do_case (start, end) + tree start, end; +{ + tree value1 = NULL_TREE, value2 = NULL_TREE, label; + + if (start != NULL_TREE && TREE_TYPE (start) != NULL_TREE + && POINTER_TYPE_P (TREE_TYPE (start))) + error ("pointers are not permitted as case values"); + + if (end && pedantic) + pedwarn ("ANSI C++ forbids range expressions in switch statement"); + + if (processing_template_decl) + { + add_tree (build_min_nt (CASE_LABEL, start, end)); + return; + } + + if (start) + value1 = check_cp_case_value (start); + if (end) + value2 = check_cp_case_value (end); + + label = build_decl (LABEL_DECL, NULL_TREE, NULL_TREE); + + if (value1 != error_mark_node + && value2 != error_mark_node) + { + tree duplicate; + int success; + + if (end) + success = pushcase_range (value1, value2, convert_and_check, + label, &duplicate); + else if (start) + success = pushcase (value1, convert_and_check, label, &duplicate); + else + success = pushcase (NULL_TREE, 0, label, &duplicate); + + if (success == 1) + { + if (end) + error ("case label not within a switch statement"); + else if (start) + cp_error ("case label `%E' not within a switch statement", start); + else + error ("default label not within a switch statement"); + } + else if (success == 2) + { + if (end) + { + error ("duplicate (or overlapping) case value"); + cp_error_at ("this is the first entry overlapping that value", + duplicate); + } + else if (start) + { + cp_error ("duplicate case value `%E'", start); + cp_error_at ("previously used here", duplicate); + } + else + { + error ("multiple default labels in one switch"); + cp_error_at ("this is the first default label", duplicate); + } + } + else if (success == 3) + warning ("case value out of range"); + else if (success == 4) + warning ("empty range specified"); + else if (success == 5) + { + if (end) + error ("case label within scope of cleanup or variable array"); + else if (! start) + error ("`default' label within scope of cleanup or variable array"); + else + cp_error ("case label `%E' within scope of cleanup or variable array", start); + } + } + define_case_label (); +} |