![[BACK]](/cvsweb/icons/back.gif){kind=icon}
Return to cp-expr.c CVS log ![[TXT]](/cvsweb/icons/text.gif){kind=icon}
![[DIR]](/cvsweb/icons/dir.gif){kind=icon}
Up to [GCC 2.x] / gcc|
Return to cp-expr.c CVS log | Up to [GCC 2.x] / gcc |
1.1 root 1: /* Convert language-specific tree expression to rtl instructions,
2: for GNU compiler.
3: Copyright (C) 1988, 1992 Free Software Foundation, Inc.
4:
5: This file is part of GNU CC.
6:
7: GNU CC is free software; you can redistribute it and/or modify
8: it under the terms of the GNU General Public License as published by
9: the Free Software Foundation; either version 2, or (at your option)
10: any later version.
11:
12: GNU CC is distributed in the hope that it will be useful,
13: but WITHOUT ANY WARRANTY; without even the implied warranty of
14: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15: GNU General Public License for more details.
16:
17: You should have received a copy of the GNU General Public License
18: along with GNU CC; see the file COPYING. If not, write to
19: the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
20:
21:
22: #include "config.h"
23: #include "rtl.h"
24: #include "tree.h"
25: #include "flags.h"
26: #include "expr.h"
27: #include "cp-tree.h"
28: #include "assert.h"
29:
30: #define NULL 0
31:
32: /* Hook used by expand_expr to expand language-specific tree codes. */
33:
34: rtx
35: cplus_expand_expr (exp, target, tmode, modifier)
36: tree exp;
37: rtx target;
38: enum machine_mode tmode;
39: enum expand_modifier modifier;
40: {
41: tree type = TREE_TYPE (exp);
42: register enum machine_mode mode = TYPE_MODE (type);
43: register enum tree_code code = TREE_CODE (exp);
44: rtx original_target = target;
45: int ignore = target == const0_rtx;
46:
47: if (ignore) target = 0, original_target = 0;
48:
49: /* No sense saving up arithmetic to be done
50: if it's all in the wrong mode to form part of an address.
51: And force_operand won't know whether to sign-extend or zero-extend. */
52:
53: if (mode != Pmode && modifier == EXPAND_SUM)
54: modifier = EXPAND_NORMAL;
55:
56: switch (code)
57: {
58: case NEW_EXPR:
59: {
60: /* Something needs to be initialized, but we didn't know
61: where that thing was when building the tree. For example,
62: it could be the return value of a function, or a parameter
63: to a function which lays down in the stack, or a temporary
64: variable which must be passed by reference.
65:
66: Cleanups are handled in a language-specific way: they
67: might be run by the called function (true in GNU C++
68: for parameters with cleanups), or they might be
69: run by the caller, after the call (true in GNU C++
70: for other cleanup needs). */
71:
72: tree func = TREE_OPERAND (exp, 0);
73: tree args = TREE_OPERAND (exp, 1);
74: tree type = TREE_TYPE (exp), slot;
75: tree fn_type = TREE_TYPE (TREE_TYPE (func));
76: tree return_type = TREE_TYPE (fn_type);
77: rtx call_target, return_target;
78:
79: /* The expression `init' wants to initialize what
80: `target' represents. SLOT holds the slot for TARGET. */
81: slot = TREE_OPERAND (exp, 2);
82:
83: if (target == 0)
84: {
85: /* Should always be called with a target in BLKmode case. */
86: assert (mode != BLKmode);
87: assert (DECL_RTL (slot) != 0);
88:
89: target = gen_reg_rtx (mode);
90: }
91:
92: /* The target the initializer will initialize (CALL_TARGET)
93: must now be directed to initialize the target we are
94: supposed to initialize (TARGET). The semantics for
95: choosing what CALL_TARGET is is language-specific,
96: as is building the call which will perform the
97: initialization. It is left here to show the choices that
98: exist for C++. */
99:
100: if (TREE_CODE (func) == ADDR_EXPR
101: && TREE_CODE (TREE_OPERAND (func, 0)) == FUNCTION_DECL
102: && DECL_CONSTRUCTOR_P (TREE_OPERAND (func, 0)))
103: {
104: type = TYPE_POINTER_TO (type);
105: /* Don't clobber a value that might be part of a default
106: parameter value. */
107: if (TREE_PERMANENT (args))
108: args = tree_cons (0, build1 (ADDR_EXPR, type, slot),
109: TREE_CHAIN (args));
110: else
111: TREE_VALUE (args) = build1 (ADDR_EXPR, type, slot);
112: call_target = 0;
113: }
114: else if (TREE_CODE (return_type) == REFERENCE_TYPE)
115: {
116: type = return_type;
117: call_target = 0;
118: }
119: else
120: {
121: call_target = target;
122: }
123: if (call_target)
124: preserve_temp_slots (call_target);
125: preserve_temp_slots (DECL_RTL (slot));
126: return_target = expand_expr (build (CALL_EXPR, type, func, args, 0), call_target, mode, 0);
127: free_temp_slots ();
128: if (call_target == 0)
129: call_target = return_target;
130: else if (call_target != return_target)
131: {
132: if (GET_MODE (return_target) == BLKmode)
133: emit_block_move (call_target, return_target, expr_size (exp),
134: TYPE_ALIGN (type) / BITS_PER_UNIT);
135: else
136: emit_move_insn (call_target, return_target);
137: }
138:
139: if (TREE_CODE (return_type) == REFERENCE_TYPE)
140: {
141: tree init;
142:
143: if (GET_CODE (call_target) == REG
144: && REGNO (call_target) < FIRST_PSEUDO_REGISTER)
1.1.1.3 ! root 145: my_friendly_abort (39);
1.1 root 146:
147: type = TREE_TYPE (exp);
148:
149: init = build (RTL_EXPR, return_type, 0, call_target);
1.1.1.2 root 150: /* We got back a reference to the type we want. Now initialize
1.1 root 151: target with that. */
152: expand_aggr_init (slot, init, 0);
153: }
154:
155: if (DECL_RTL (slot) != target)
156: emit_move_insn (DECL_RTL (slot), target);
157: return DECL_RTL (slot);
158: }
159:
160: case OFFSET_REF:
161: {
162: tree base = build_unary_op (ADDR_EXPR, TREE_OPERAND (exp, 0), 0);
163: tree offset = build_unary_op (ADDR_EXPR, TREE_OPERAND (exp, 1), 0);
164: return expand_expr (build (PLUS_EXPR, TREE_TYPE (exp), base, offset),
165: target, tmode, EXPAND_NORMAL);
166: }
167:
168: default:
169: break;
170: }
1.1.1.3 ! root 171: my_friendly_abort (40);
1.1 root 172: /* NOTREACHED */
173: return NULL;
174: }
175:
176: void
177: init_cplus_expand ()
178: {
179: lang_expand_expr = cplus_expand_expr;
180: }
181:
182: /* If DECL had its rtl moved from where callers expect it
183: to be, fix it up. RESULT is the nominal rtl for the RESULT_DECL,
184: which may be a pseudo instead of a hard register. */
185:
186: void
187: fixup_result_decl (decl, result)
188: tree decl;
189: rtx result;
190: {
191: if (REG_P (result))
192: {
193: if (REGNO (result) >= FIRST_PSEUDO_REGISTER)
194: {
195: rtx real_decl_result;
196:
197: #ifdef FUNCTION_OUTGOING_VALUE
198: real_decl_result
199: = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl), current_function_decl);
200: #else
201: real_decl_result
202: = FUNCTION_VALUE (TREE_TYPE (decl), current_function_decl);
203: #endif
204: REG_FUNCTION_VALUE_P (real_decl_result) = 1;
205: result = real_decl_result;
206: }
207: emit_move_insn (result, DECL_RTL (decl));
208: emit_insn (gen_rtx (USE, VOIDmode, result));
209: }
210: }
211:
212: /* Return nonzero iff DECL is memory-based. The DECL_RTL of
213: certain const variables might be a CONST_INT, or a REG
214: in some cases. We cannot use `memory_operand' as a test
215: here because on most RISC machines, a variable's address
216: is not, by itself, a legitimate address. */
217: int
218: decl_in_memory_p (decl)
219: tree decl;
220: {
221: return DECL_RTL (decl) != 0 && GET_CODE (DECL_RTL (decl)) == MEM;
222: }
This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.