1 /*
2 * Copyright (c) 1997, 2010, 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 // A frame represents a physical stack frame (an activation). Frames can be
26 // C or Java frames, and the Java frames can be interpreted or compiled.
27 // In contrast, vframes represent source-level activations, so that one physical frame
28 // can correspond to multiple source level frames because of inlining.
29 // A frame is comprised of {pc, sp, younger_sp}
30
31
32 // Layout of asm interpreter frame:
33 //
34 // 0xfffffff
35 // ......
36 // [last extra incoming arg, (local # Nargs > 6 ? Nargs-1 : undef)]
37 // .. Note: incoming args are copied to local frame area upon entry
38 // [first extra incoming arg, (local # Nargs > 6 ? 6 : undef)]
39 // [6 words for C-arg storage (unused)] Are this and next one really needed?
40 // [C-aggregate-word (unused)] Yes, if want extra params to be in same place as C convention
41 // [16 words for register saving] <--- FP
42 // [interpreter_frame_vm_locals ] (see below)
43
44 // Note: Llocals is always double-word aligned
45 // [first local i.e. local # 0] <-- Llocals
46 // ...
47 // [last local, i.e. local # Nlocals-1]
48
49 // [monitors ]
50 // ....
51 // [monitors ] <-- Lmonitors (same as Llocals + 6*4 if none)
52 // (must be double-word aligned because
53 // monitor element size is constrained to
54 // doubleword)
55 //
56 // <-- Lesp (points 1 past TOS)
57 // [bottom word used for stack ]
58 // ...
59 // [top word used for stack] (first word of stack is double-word aligned)
60
61 // [space for outgoing args (conservatively allocated as max_stack - 6 + interpreter_frame_extra_outgoing_argument_words)]
62 // [6 words for C-arg storage]
63 // [C-aggregate-word (unused)]
64 // [16 words for register saving] <--- SP
65 // ...
66 // 0x0000000
67 //
68 // The in registers and local registers are preserved in a block at SP.
69 //
70 // The first six in registers (I0..I5) hold the first six locals.
71 // The locals are used as follows:
72 // Lesp first free element of expression stack
73 // (which grows towards __higher__ addresses)
74 // Lbcp is set to address of bytecode to execute
75 // It is accessed in the frame under the name "bcx".
76 // It may at times (during GC) be an index instead.
77 // Lmethod the method being interpreted
78 // Llocals the base pointer for accessing the locals array
79 // (lower-numbered locals have lower addresses)
80 // Lmonitors the base pointer for accessing active monitors
81 // Lcache a saved pointer to the method's constant pool cache
82 //
83 //
84 // When calling out to another method,
85 // G5_method is set to method to call, G5_inline_cache_klass may be set,
86 // parameters are put in O registers, and also extra parameters
87 // must be cleverly copied from the top of stack to the outgoing param area in the frame,
88 // ------------------------------ C++ interpreter ----------------------------------------
89 // Layout of C++ interpreter frame:
90 //
91
92
93
94 // All frames:
95
96 public:
97
98 enum {
99 // normal return address is 2 words past PC
100 pc_return_offset = 2 * BytesPerInstWord,
101
102 // size of each block, in order of increasing address:
103 register_save_words = 16,
104 #ifdef _LP64
105 callee_aggregate_return_pointer_words = 0,
106 #else
107 callee_aggregate_return_pointer_words = 1,
108 #endif
109 callee_register_argument_save_area_words = 6,
110 // memory_parameter_words = <arbitrary>,
111
112 // offset of each block, in order of increasing address:
113 // (note: callee_register_argument_save_area_words == Assembler::n_register_parameters)
114 register_save_words_sp_offset = 0,
115 callee_aggregate_return_pointer_sp_offset = register_save_words_sp_offset + register_save_words,
116 callee_register_argument_save_area_sp_offset = callee_aggregate_return_pointer_sp_offset + callee_aggregate_return_pointer_words,
117 memory_parameter_word_sp_offset = callee_register_argument_save_area_sp_offset + callee_register_argument_save_area_words,
118 varargs_offset = memory_parameter_word_sp_offset
119 };
120
121 private:
122 intptr_t* _younger_sp; // optional SP of callee (used to locate O7)
123 int _sp_adjustment_by_callee; // adjustment in words to SP by callee for making locals contiguous
124
125 // Note: On SPARC, unlike Intel, the saved PC for a stack frame
126 // is stored at a __variable__ distance from that frame's SP.
127 // (In fact, it may be in the register save area of the callee frame,
128 // but that fact need not bother us.) Thus, we must store the
129 // address of that saved PC explicitly. On the other hand, SPARC
130 // stores the FP for a frame at a fixed offset from the frame's SP,
131 // so there is no need for a separate "frame::_fp" field.
132
133 public:
134 // Accessors
135
136 intptr_t* younger_sp() const {
137 assert(_younger_sp != NULL, "frame must possess a younger_sp");
138 return _younger_sp;
139 }
140
141 int callee_sp_adjustment() const { return _sp_adjustment_by_callee; }
142 void set_sp_adjustment_by_callee(int number_of_words) { _sp_adjustment_by_callee = number_of_words; }
143
144 // Constructors
145
146 // This constructor relies on the fact that the creator of a frame
147 // has flushed register windows which the frame will refer to, and
148 // that those register windows will not be reloaded until the frame is
149 // done reading and writing the stack. Moreover, if the "younger_sp"
150 // argument points into the register save area of the next younger
151 // frame (though it need not), the register window for that next
152 // younger frame must also stay flushed. (The caller is responsible
153 // for ensuring this.)
154
155 frame(intptr_t* sp, intptr_t* younger_sp, bool younger_frame_adjusted_stack = false);
156
157 // make a deficient frame which doesn't know where its PC is:
158 enum unpatchable_t { unpatchable };
159 frame(intptr_t* sp, unpatchable_t, address pc = NULL, CodeBlob* cb = NULL);
160
161 // Walk from sp outward looking for old_sp, and return old_sp's predecessor
162 // (i.e. return the sp from the frame where old_sp is the fp).
163 // Register windows are assumed to be flushed for the stack in question.
164
165 static intptr_t* next_younger_sp_or_null(intptr_t* old_sp, intptr_t* sp);
166
167 // Return true if sp is a younger sp in the stack described by valid_sp.
168 static bool is_valid_stack_pointer(intptr_t* valid_sp, intptr_t* sp);
169
170 public:
171 // accessors for the instance variables
172 intptr_t* fp() const { return (intptr_t*) ((intptr_t)(sp()[FP->sp_offset_in_saved_window()]) + STACK_BIAS ); }
173
174 // All frames
175
176 intptr_t* fp_addr_at(int index) const { return &fp()[index]; }
177 intptr_t* sp_addr_at(int index) const { return &sp()[index]; }
178 intptr_t fp_at( int index) const { return *fp_addr_at(index); }
179 intptr_t sp_at( int index) const { return *sp_addr_at(index); }
180
181 private:
182 inline address* I7_addr() const;
183 inline address* O7_addr() const;
184
185 inline address* I0_addr() const;
186 inline address* O0_addr() const;
187 intptr_t* younger_sp_addr_at(int index) const { return &younger_sp()[index]; }
188
189 public:
190 // access to SPARC arguments and argument registers
191
192 // Assumes reg is an in/local register
193 intptr_t* register_addr(Register reg) const {
194 return sp_addr_at(reg->sp_offset_in_saved_window());
195 }
196
197 // Assumes reg is an out register
198 intptr_t* out_register_addr(Register reg) const {
199 return younger_sp_addr_at(reg->after_save()->sp_offset_in_saved_window());
200 }
201 intptr_t* memory_param_addr(int param_ix, bool is_in) const {
202 int offset = callee_register_argument_save_area_sp_offset + param_ix;
203 if (is_in)
204 return fp_addr_at(offset);
205 else
206 return sp_addr_at(offset);
207 }
208 intptr_t* param_addr(int param_ix, bool is_in) const {
209 if (param_ix >= callee_register_argument_save_area_words)
210 return memory_param_addr(param_ix, is_in);
211 else if (is_in)
212 return register_addr(Argument(param_ix, true).as_register());
213 else {
214 // the registers are stored in the next younger frame
215 // %%% is this really necessary?
216 ShouldNotReachHere();
217 return NULL;
218 }
219 }
220
221
222 // Interpreter frames
223
224 public:
225 // Asm interpreter
226 #ifndef CC_INTERP
227 enum interpreter_frame_vm_locals {
228 // 2 words, also used to save float regs across calls to C
229 interpreter_frame_d_scratch_fp_offset = -2,
230 interpreter_frame_l_scratch_fp_offset = -4,
231 interpreter_frame_padding_offset = -5, // for native calls only
232 interpreter_frame_oop_temp_offset = -6, // for native calls only
233 interpreter_frame_vm_locals_fp_offset = -6, // should be same as above, and should be zero mod 8
234
235 interpreter_frame_vm_local_words = -interpreter_frame_vm_locals_fp_offset,
236
237
238 // interpreter frame set-up needs to save 2 extra words in outgoing param area
239 // for class and jnienv arguments for native stubs (see nativeStubGen_sparc.cpp_
240
241 interpreter_frame_extra_outgoing_argument_words = 2
242 };
243 #else
244 enum interpreter_frame_vm_locals {
245 // 2 words, also used to save float regs across calls to C
246 interpreter_state_ptr_offset = 0, // Is in L0 (Lstate) in save area
247 interpreter_frame_mirror_offset = 1, // Is in L1 (Lmirror) in save area (for native calls only)
248
249 // interpreter frame set-up needs to save 2 extra words in outgoing param area
250 // for class and jnienv arguments for native stubs (see nativeStubGen_sparc.cpp_
251
252 interpreter_frame_extra_outgoing_argument_words = 2
253 };
254 #endif /* CC_INTERP */
255
256 // the compiler frame has many of the same fields as the interpreter frame
257 // %%%%% factor out declarations of the shared fields
258 enum compiler_frame_fixed_locals {
259 compiler_frame_d_scratch_fp_offset = -2,
260 compiler_frame_vm_locals_fp_offset = -2, // should be same as above
261
262 compiler_frame_vm_local_words = -compiler_frame_vm_locals_fp_offset
263 };
264
265 private:
266 constantPoolCacheOop* interpreter_frame_cpoolcache_addr() const;
267
268 #ifndef CC_INTERP
269
270 // where Lmonitors is saved:
271 BasicObjectLock** interpreter_frame_monitors_addr() const {
272 return (BasicObjectLock**) sp_addr_at(Lmonitors->sp_offset_in_saved_window());
273 }
274 intptr_t** interpreter_frame_esp_addr() const {
275 return (intptr_t**)sp_addr_at(Lesp->sp_offset_in_saved_window());
276 }
277
278 inline void interpreter_frame_set_tos_address(intptr_t* x);
279
280
281 // %%%%% Another idea: instead of defining 3 fns per item, just define one returning a ref
282
283 // monitors:
284
285 // next two fns read and write Lmonitors value,
286 private:
287 BasicObjectLock* interpreter_frame_monitors() const { return *interpreter_frame_monitors_addr(); }
288 void interpreter_frame_set_monitors(BasicObjectLock* monitors) { *interpreter_frame_monitors_addr() = monitors; }
289 #else
290 public:
291 inline interpreterState get_interpreterState() const {
292 return ((interpreterState)sp_at(interpreter_state_ptr_offset));
293 }
294
295
296 #endif /* CC_INTERP */
297
298
299
300 // Compiled frames
301
302 public:
303 // Tells if this register can hold 64 bits on V9 (really, V8+).
304 static bool holds_a_doubleword(Register reg) {
305 #ifdef _LP64
306 // return true;
307 return reg->is_out() || reg->is_global();
308 #else
309 return reg->is_out() || reg->is_global();
310 #endif
311 }