1 /*
2 * Copyright (c) 1997, 2026, 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.
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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.
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23 */
24
25 #ifndef CPU_X86_FRAME_X86_HPP
26 #define CPU_X86_FRAME_X86_HPP
27
28 // A frame represents a physical stack frame (an activation). Frames can be
29 // C or Java frames, and the Java frames can be interpreted or compiled.
30 // In contrast, vframes represent source-level activations, so that one physical frame
31 // can correspond to multiple source level frames because of inlining.
32 // A frame is comprised of {pc, fp, sp}
33 // ------------------------------ Asm interpreter ----------------------------------------
34 // Layout of asm interpreter frame:
35 // [expression stack ] * <- sp
36 // [monitors ] \
37 // ... | monitor block size
38 // [monitors ] /
39 // [monitor block size ]
40 // [byte code pointer ] = bcp() bcp_offset
41 // [pointer to locals ] = locals() locals_offset
42 // [constant pool cache ] = cache() cache_offset
43 // [methodData ] = mdp() mdx_offset
44 // [klass of method ] = mirror() mirror_offset
45 // [Method* ] = method() method_offset
46 // [last sp ] = last_sp() last_sp_offset
47 // [old stack pointer ] (sender_sp) sender_sp_offset
48 // [old frame pointer ] <- fp = link()
49 // [return pc ]
50 // [oop temp ] (only for native calls)
51 // [locals and parameters ]
52 // <- sender sp
53 // ------------------------------ Asm interpreter ----------------------------------------
54
55 public:
56 enum {
57 // All frames
58 link_offset = 0,
59 return_addr_offset = 1,
60 // non-interpreter frames
61 sender_sp_offset = 2,
62
63 // Interpreter frames
64 interpreter_frame_result_handler_offset = 3, // for native calls only
65 interpreter_frame_oop_temp_offset = 2, // for native calls only
66
67 interpreter_frame_sender_sp_offset = -1,
68 // outgoing sp before a call to an invoked method
69 interpreter_frame_last_sp_offset = interpreter_frame_sender_sp_offset - 1,
70 interpreter_frame_method_offset = interpreter_frame_last_sp_offset - 1,
71 interpreter_frame_mirror_offset = interpreter_frame_method_offset - 1,
72 interpreter_frame_mdp_offset = interpreter_frame_mirror_offset - 1,
73 interpreter_frame_cache_offset = interpreter_frame_mdp_offset - 1,
74 interpreter_frame_locals_offset = interpreter_frame_cache_offset - 1,
75 interpreter_frame_bcp_offset = interpreter_frame_locals_offset - 1,
76 interpreter_frame_initial_sp_offset = interpreter_frame_bcp_offset - 1,
77
78 interpreter_frame_monitor_block_top_offset = interpreter_frame_initial_sp_offset,
79 interpreter_frame_monitor_block_bottom_offset = interpreter_frame_initial_sp_offset,
80
81 // Entry frames
82 #ifdef _WINDOWS
83 entry_frame_after_call_words = 28,
84 entry_frame_call_wrapper_offset = 2,
85
86 arg_reg_save_area_bytes = 32, // Register argument save area
87 #else
88 entry_frame_after_call_words = 13,
89 entry_frame_call_wrapper_offset = -6,
90
91 arg_reg_save_area_bytes = 0,
92 #endif // _WINDOWS
93
94 // size, in words, of frame metadata (e.g. pc and link)
95 metadata_words = sender_sp_offset,
96 // size, in words, of metadata at frame bottom, i.e. it is not part of the
97 // caller/callee overlap
98 metadata_words_at_bottom = metadata_words,
99 // size, in words, of frame metadata at the frame top, i.e. it is located
100 // between a callee frame and its stack arguments, where it is part
101 // of the caller/callee overlap
102 metadata_words_at_top = 0,
103 // in bytes
104 frame_alignment = 16,
105 // size, in words, of maximum shift in frame position due to alignment
106 align_wiggle = 1
107 };
108
109 intptr_t ptr_at(int offset) const {
110 return *ptr_at_addr(offset);
111 }
112
113 void ptr_at_put(int offset, intptr_t value) {
114 *ptr_at_addr(offset) = value;
115 }
116
117 private:
118 // an additional field beyond _sp and _pc:
119 union {
120 intptr_t* _fp; // frame pointer
121 int _offset_fp; // relative frame pointer for use in stack-chunk frames
122 };
123 // The interpreter and adapters will extend the frame of the caller.
124 // Since oopMaps are based on the sp of the caller before extension
125 // we need to know that value. However in order to compute the address
126 // of the return address we need the real "raw" sp. By convention we
127 // use sp() to mean "raw" sp and unextended_sp() to mean the caller's
128 // original sp.
129
130 union {
131 intptr_t* _unextended_sp;
132 int _offset_unextended_sp; // for use in stack-chunk frames
133 };
134
135 intptr_t* ptr_at_addr(int offset) const {
136 return (intptr_t*) addr_at(offset);
137 }
138
139 public:
140 // Constructors
141
142 frame(intptr_t* sp, intptr_t* fp, address pc);
143
144 frame(intptr_t* sp, intptr_t* unextended_sp, intptr_t* fp, address pc);
145
146 frame(intptr_t* sp, intptr_t* unextended_sp, intptr_t* fp, address pc, CodeBlob* cb);
147 // used for heap frame construction by continuations
148 frame(intptr_t* sp, intptr_t* unextended_sp, intptr_t* fp, address pc, CodeBlob* cb, const ImmutableOopMap* oop_map, bool relative);
149
150 frame(intptr_t* sp, intptr_t* fp);
151
152 void init(intptr_t* sp, intptr_t* fp, address pc);
153 void setup(address pc);
154
155 // accessors for the instance variables
156 // Note: not necessarily the real 'frame pointer' (see real_fp)
157 intptr_t* fp() const { assert_absolute(); return _fp; }
158 void set_fp(intptr_t* newfp) { _fp = newfp; }
159 int offset_fp() const { assert_offset(); return _offset_fp; }
160 void set_offset_fp(int value) { assert_on_heap(); _offset_fp = value; }
161
162 inline address* sender_pc_addr() const;
163
164 // expression stack tos if we are nested in a java call
165 intptr_t* interpreter_frame_last_sp() const;
166
167 template <typename RegisterMapT>
168 static void update_map_with_saved_link(RegisterMapT* map, intptr_t** link_addr);
169
170 // deoptimization support
171 void interpreter_frame_set_last_sp(intptr_t* sp);
172
173 static jint interpreter_frame_expression_stack_direction() { return -1; }
174
175 // returns the sending frame, without applying any barriers
176 inline frame sender_raw(RegisterMap* map) const;
177
178 #endif // CPU_X86_FRAME_X86_HPP