1 /*
2 * Copyright (c) 1999, 2006, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 class ValueStack: public CompilationResourceObj {
26 public:
27 enum Kind {
28 Parsing, // During abstract interpretation in GraphBuilder
29 CallerState, // Caller state when inlining
30 StateBefore, // Before before execution of instruction
31 StateAfter, // After execution of instruction
32 ExceptionState, // Exception handling of instruction
33 EmptyExceptionState, // Exception handling of instructions not covered by an xhandler
34 BlockBeginState // State of BlockBegin instruction with phi functions of this block
35 };
36
37 private:
38 IRScope* _scope; // the enclosing scope
39 ValueStack* _caller_state;
40 int _bci;
41 Kind _kind;
42
43 Values _locals; // the locals
44 Values _stack; // the expression stack
45 Values _locks; // the monitor stack (holding the locked values)
46
47 Value check(ValueTag tag, Value t) {
48 assert(tag == t->type()->tag() || tag == objectTag && t->type()->tag() == addressTag, "types must correspond");
49 return t;
50 }
51
52 Value check(ValueTag tag, Value t, Value h) {
53 assert(h == NULL, "hi-word of doubleword value must be NULL");
54 return check(tag, t);
55 }
56
57 // helper routine
58 static void apply(Values list, ValueVisitor* f);
59
60 // for simplified copying
61 ValueStack(ValueStack* copy_from, Kind kind, int bci);
62
63 public:
64 // creation
65 ValueStack(IRScope* scope, ValueStack* caller_state);
66
67 ValueStack* copy() { return new ValueStack(this, _kind, _bci); }
68 ValueStack* copy(Kind new_kind, int new_bci) { return new ValueStack(this, new_kind, new_bci); }
69 ValueStack* copy_for_parsing() { return new ValueStack(this, Parsing, -99); }
70
71 void set_caller_state(ValueStack* s) {
72 assert(kind() == EmptyExceptionState ||
73 (Compilation::current()->env()->jvmti_can_access_local_variables() && kind() == ExceptionState),
74 "only EmptyExceptionStates can be modified");
75 _caller_state = s;
76 }
77
78 bool is_same(ValueStack* s); // returns true if this & s's types match (w/o checking locals)
79
80 // accessors
81 IRScope* scope() const { return _scope; }
82 ValueStack* caller_state() const { return _caller_state; }
83 int bci() const { return _bci; }
84 Kind kind() const { return _kind; }
85
86 int locals_size() const { return _locals.length(); }
87 int stack_size() const { return _stack.length(); }
88 int locks_size() const { return _locks.length(); }
89 bool stack_is_empty() const { return _stack.is_empty(); }
90 bool no_active_locks() const { return _locks.is_empty(); }
91 int total_locks_size() const;
92
93 // locals access
94 void clear_locals(); // sets all locals to NULL;
95
96 void invalidate_local(int i) {
97 assert(_locals.at(i)->type()->is_single_word() ||
98 _locals.at(i + 1) == NULL, "hi-word of doubleword value must be NULL");
99 _locals.at_put(i, NULL);
100 }
101
102 Value local_at(int i) const {
103 Value x = _locals.at(i);
104 assert(x == NULL || x->type()->is_single_word() ||
105 _locals.at(i + 1) == NULL, "hi-word of doubleword value must be NULL");
106 return x;
107 }
108
109 void store_local(int i, Value x) {
110 // When overwriting local i, check if i - 1 was the start of a
111 // double word local and kill it.
112 if (i > 0) {
113 Value prev = _locals.at(i - 1);
114 if (prev != NULL && prev->type()->is_double_word()) {
115 _locals.at_put(i - 1, NULL);
116 }
117 }
118
119 _locals.at_put(i, x);
120 if (x->type()->is_double_word()) {
121 // hi-word of doubleword value is always NULL
122 _locals.at_put(i + 1, NULL);
123 }
124 }
125
126 // stack access
127 Value stack_at(int i) const {
128 Value x = _stack.at(i);
129 assert(x->type()->is_single_word() ||
130 _stack.at(i + 1) == NULL, "hi-word of doubleword value must be NULL");
131 return x;
132 }
133
134 Value stack_at_inc(int& i) const {
135 Value x = stack_at(i);
136 i += x->type()->size();
137 return x;
138 }
139
140 // pinning support
141 void pin_stack_for_linear_scan();
142
143 // iteration
144 void values_do(ValueVisitor* f);
145
146 // untyped manipulation (for dup_x1, etc.)
147 void truncate_stack(int size) { _stack.trunc_to(size); }
148 void raw_push(Value t) { _stack.push(t); }
149 Value raw_pop() { return _stack.pop(); }
150
151 // typed manipulation
152 void ipush(Value t) { _stack.push(check(intTag , t)); }
153 void fpush(Value t) { _stack.push(check(floatTag , t)); }
154 void apush(Value t) { _stack.push(check(objectTag , t)); }
155 void rpush(Value t) { _stack.push(check(addressTag, t)); }
156 void lpush(Value t) { _stack.push(check(longTag , t)); _stack.push(NULL); }
157 void dpush(Value t) { _stack.push(check(doubleTag , t)); _stack.push(NULL); }
158
159 void push(ValueType* type, Value t) {
160 switch (type->tag()) {
161 case intTag : ipush(t); return;
162 case longTag : lpush(t); return;
163 case floatTag : fpush(t); return;
164 case doubleTag : dpush(t); return;
165 case objectTag : apush(t); return;
166 case addressTag: rpush(t); return;
167 }
168 ShouldNotReachHere();
169 }
170
171 Value ipop() { return check(intTag , _stack.pop()); }
172 Value fpop() { return check(floatTag , _stack.pop()); }
173 Value apop() { return check(objectTag , _stack.pop()); }
174 Value rpop() { return check(addressTag, _stack.pop()); }
175 Value lpop() { Value h = _stack.pop(); return check(longTag , _stack.pop(), h); }
176 Value dpop() { Value h = _stack.pop(); return check(doubleTag, _stack.pop(), h); }
177
178 Value pop(ValueType* type) {
179 switch (type->tag()) {
180 case intTag : return ipop();
181 case longTag : return lpop();
182 case floatTag : return fpop();
183 case doubleTag : return dpop();
184 case objectTag : return apop();
185 case addressTag: return rpop();
186 }
187 ShouldNotReachHere();
188 return NULL;
189 }
190
191 Values* pop_arguments(int argument_size);
192
193 // locks access
194 int lock (Value obj);
195 int unlock();
196 Value lock_at(int i) const { return _locks.at(i); }
197
198 // SSA form IR support
199 void setup_phi_for_stack(BlockBegin* b, int index);
200 void setup_phi_for_local(BlockBegin* b, int index);
201
202 // debugging
203 void print() PRODUCT_RETURN;
204 void verify() PRODUCT_RETURN;
205 };
206
207
208
209 // Macro definitions for simple iteration of stack and local values of a ValueStack
210 // The macros can be used like a for-loop. All variables (state, index and value)
211 // must be defined before the loop.
212 // When states are nested because of inlining, the stack of the innermost state
213 // cumulates also the stack of the nested states. In contrast, the locals of all
214 // states must be iterated each.
215 // Use the following code pattern to iterate all stack values and all nested local values:
216 //
217 // ValueStack* state = ... // state that is iterated
218 // int index; // current loop index (overwritten in loop)
219 // Value value; // value at current loop index (overwritten in loop)
220 //
221 // for_each_stack_value(state, index, value {
222 // do something with value and index
223 // }
224 //
225 // for_each_state(state) {
226 // for_each_local_value(state, index, value) {
227 // do something with value and index
228 // }
229 // }
230 // as an invariant, state is NULL now
231
232
233 // construct a unique variable name with the line number where the macro is used
234 #define temp_var3(x) temp__ ## x
235 #define temp_var2(x) temp_var3(x)
236 #define temp_var temp_var2(__LINE__)
237
238 #define for_each_state(state) \
239 for (; state != NULL; state = state->caller_state())
240
241 #define for_each_local_value(state, index, value) \
242 int temp_var = state->locals_size(); \
243 for (index = 0; \
244 index < temp_var && (value = state->local_at(index), true); \
245 index += (value == NULL || value->type()->is_illegal() ? 1 : value->type()->size())) \
246 if (value != NULL)
247
248
249 #define for_each_stack_value(state, index, value) \
250 int temp_var = state->stack_size(); \
251 for (index = 0; \
252 index < temp_var && (value = state->stack_at(index), true); \
253 index += value->type()->size())
254
255
256 #define for_each_lock_value(state, index, value) \
257 int temp_var = state->locks_size(); \
258 for (index = 0; \
259 index < temp_var && (value = state->lock_at(index), true); \
260 index++) \
261 if (value != NULL)
262
263
264 // Macro definition for simple iteration of all state values of a ValueStack
265 // Because the code cannot be executed in a single loop, the code must be passed
266 // as a macro parameter.
267 // Use the following code pattern to iterate all stack values and all nested local values:
268 //
269 // ValueStack* state = ... // state that is iterated
270 // for_each_state_value(state, value,
271 // do something with value (note that this is a macro parameter)
272 // );
273
274 #define for_each_state_value(v_state, v_value, v_code) \
275 { \
276 int cur_index; \
277 ValueStack* cur_state = v_state; \
278 Value v_value; \
279 for_each_state(cur_state) { \
280 { \
281 for_each_local_value(cur_state, cur_index, v_value) { \
282 v_code; \
283 } \
284 } \
285 { \
286 for_each_stack_value(cur_state, cur_index, v_value) { \
287 v_code; \
288 } \
289 } \
290 } \
291 }
292
293
294 // Macro definition for simple iteration of all phif functions of a block, i.e all
295 // phi functions of the ValueStack where the block matches.
296 // Use the following code pattern to iterate all phi functions of a block:
297 //
298 // BlockBegin* block = ... // block that is iterated
299 // for_each_phi_function(block, phi,
300 // do something with the phi function phi (note that this is a macro parameter)
301 // );
302
303 #define for_each_phi_fun(v_block, v_phi, v_code) \
304 { \
305 int cur_index; \
306 ValueStack* cur_state = v_block->state(); \
307 Value value; \
308 { \
309 for_each_stack_value(cur_state, cur_index, value) { \
310 Phi* v_phi = value->as_Phi(); \
311 if (v_phi != NULL && v_phi->block() == v_block) { \
312 v_code; \
313 } \
314 } \
315 } \
316 { \
317 for_each_local_value(cur_state, cur_index, value) { \
318 Phi* v_phi = value->as_Phi(); \
319 if (v_phi != NULL && v_phi->block() == v_block) { \
320 v_code; \
321 } \
322 } \
323 } \
324 }