1/*
2 * Copyright (c) 2003, 2016, Oracle and/or its affiliates. All rights reserved.
3 * Copyright 2007, 2008, 2010, 2015 Red Hat, Inc.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 *
24 */
25
26#include "precompiled.hpp"
27#include "asm/assembler.hpp"
28#include "assembler_zero.inline.hpp"
29#include "interpreter/interpreter.hpp"
30#include "nativeInst_zero.hpp"
31#include "oops/instanceOop.hpp"
32#include "oops/method.hpp"
33#include "oops/objArrayKlass.hpp"
34#include "oops/oop.inline.hpp"
35#include "prims/methodHandles.hpp"
36#include "runtime/frame.inline.hpp"
37#include "runtime/handles.inline.hpp"
38#include "runtime/sharedRuntime.hpp"
39#include "runtime/stubCodeGenerator.hpp"
40#include "runtime/stubRoutines.hpp"
41#include "runtime/thread.inline.hpp"
42#include "stack_zero.inline.hpp"
43#ifdef COMPILER2
44#include "opto/runtime.hpp"
45#endif
46
47// For SafeFetch we need POSIX tls and setjmp
48#include <setjmp.h>
49#include <pthread.h>
50static pthread_key_t g_jmpbuf_key;
51
52// return the currently active jump buffer for this thread
53//  - if there is any, NULL otherwise. Called from
54//    zero signal handlers.
55extern sigjmp_buf* get_jmp_buf_for_continuation() {
56  return (sigjmp_buf*) pthread_getspecific(g_jmpbuf_key);
57}
58
59// Declaration and definition of StubGenerator (no .hpp file).
60// For a more detailed description of the stub routine structure
61// see the comment in stubRoutines.hpp
62
63class StubGenerator: public StubCodeGenerator {
64 private:
65  // The call stub is used to call Java from C
66  static void call_stub(
67    JavaCallWrapper *call_wrapper,
68    intptr_t*        result,
69    BasicType        result_type,
70    Method*          method,
71    address          entry_point,
72    intptr_t*        parameters,
73    int              parameter_words,
74    TRAPS) {
75    JavaThread *thread = (JavaThread *) THREAD;
76    ZeroStack *stack = thread->zero_stack();
77
78    // Make sure we have no pending exceptions
79    assert(!HAS_PENDING_EXCEPTION, "call_stub called with pending exception");
80
81    // Set up the stack if necessary
82    bool stack_needs_teardown = false;
83    if (stack->needs_setup()) {
84      size_t zero_stack_size = stack->suggest_size(thread);
85      stack->setup(alloca(zero_stack_size), zero_stack_size);
86      stack_needs_teardown = true;
87    }
88
89    // Allocate and initialize our frame
90    EntryFrame *frame =
91      EntryFrame::build(parameters, parameter_words, call_wrapper, THREAD);
92
93    if (!HAS_PENDING_EXCEPTION) {
94      // Push the frame
95      thread->push_zero_frame(frame);
96
97      // Make the call
98      Interpreter::invoke_method(method, entry_point, THREAD);
99
100      // Store the result
101      if (!HAS_PENDING_EXCEPTION) {
102        switch (result_type) {
103        case T_INT:
104          *(jint *) result = *(jint *) stack->sp();
105          break;
106        case T_LONG:
107          *(jlong *) result = *(jlong *) stack->sp();
108          break;
109        case T_FLOAT:
110          *(jfloat *) result = *(jfloat *) stack->sp();
111          break;
112        case T_DOUBLE:
113          *(jdouble *) result = *(jdouble *) stack->sp();
114          break;
115        case T_OBJECT:
116          *(oop *) result = *(oop *) stack->sp();
117          break;
118        default:
119          ShouldNotReachHere();
120        }
121      }
122
123      // Unwind the frame
124      thread->pop_zero_frame();
125    }
126
127    // Tear down the stack if necessary
128    if (stack_needs_teardown)
129      stack->teardown();
130  }
131
132  // These stubs get called from some dumb test routine.
133  // I'll write them properly when they're called from
134  // something that's actually doing something.
135  static void fake_arraycopy_stub(address src, address dst, int count) {
136    assert(count == 0, "huh?");
137  }
138
139  void generate_arraycopy_stubs() {
140    // Call the conjoint generation methods immediately after
141    // the disjoint ones so that short branches from the former
142    // to the latter can be generated.
143    StubRoutines::_jbyte_disjoint_arraycopy  = (address) fake_arraycopy_stub;
144    StubRoutines::_jbyte_arraycopy           = (address) fake_arraycopy_stub;
145
146    StubRoutines::_jshort_disjoint_arraycopy = (address) fake_arraycopy_stub;
147    StubRoutines::_jshort_arraycopy          = (address) fake_arraycopy_stub;
148
149    StubRoutines::_jint_disjoint_arraycopy   = (address) fake_arraycopy_stub;
150    StubRoutines::_jint_arraycopy            = (address) fake_arraycopy_stub;
151
152    StubRoutines::_jlong_disjoint_arraycopy  = (address) fake_arraycopy_stub;
153    StubRoutines::_jlong_arraycopy           = (address) fake_arraycopy_stub;
154
155    StubRoutines::_oop_disjoint_arraycopy    = ShouldNotCallThisStub();
156    StubRoutines::_oop_arraycopy             = ShouldNotCallThisStub();
157
158    StubRoutines::_checkcast_arraycopy       = ShouldNotCallThisStub();
159    StubRoutines::_unsafe_arraycopy          = ShouldNotCallThisStub();
160    StubRoutines::_generic_arraycopy         = ShouldNotCallThisStub();
161
162    // We don't generate specialized code for HeapWord-aligned source
163    // arrays, so just use the code we've already generated
164    StubRoutines::_arrayof_jbyte_disjoint_arraycopy =
165      StubRoutines::_jbyte_disjoint_arraycopy;
166    StubRoutines::_arrayof_jbyte_arraycopy =
167      StubRoutines::_jbyte_arraycopy;
168
169    StubRoutines::_arrayof_jshort_disjoint_arraycopy =
170      StubRoutines::_jshort_disjoint_arraycopy;
171    StubRoutines::_arrayof_jshort_arraycopy =
172      StubRoutines::_jshort_arraycopy;
173
174    StubRoutines::_arrayof_jint_disjoint_arraycopy =
175      StubRoutines::_jint_disjoint_arraycopy;
176    StubRoutines::_arrayof_jint_arraycopy =
177      StubRoutines::_jint_arraycopy;
178
179    StubRoutines::_arrayof_jlong_disjoint_arraycopy =
180      StubRoutines::_jlong_disjoint_arraycopy;
181    StubRoutines::_arrayof_jlong_arraycopy =
182      StubRoutines::_jlong_arraycopy;
183
184    StubRoutines::_arrayof_oop_disjoint_arraycopy =
185      StubRoutines::_oop_disjoint_arraycopy;
186    StubRoutines::_arrayof_oop_arraycopy =
187      StubRoutines::_oop_arraycopy;
188  }
189
190  static int SafeFetch32(int *adr, int errValue) {
191
192    // set up a jump buffer; anchor the pointer to the jump buffer in tls; then
193    // do the pointer access. If pointer is invalid, we crash; in signal
194    // handler, we retrieve pointer to jmp buffer from tls, and jump back.
195    //
196    // Note: the jump buffer itself - which can get pretty large depending on
197    // the architecture - lives on the stack and that is fine, because we will
198    // not rewind the stack: either we crash, in which case signal handler
199    // frame is below us, or we don't crash, in which case it does not matter.
200    sigjmp_buf jb;
201    if (sigsetjmp(jb, 1)) {
202      // we crashed. clean up tls and return default value.
203      pthread_setspecific(g_jmpbuf_key, NULL);
204      return errValue;
205    } else {
206      // preparation phase
207      pthread_setspecific(g_jmpbuf_key, &jb);
208    }
209
210    int value = errValue;
211    value = *adr;
212
213    // all went well. clean tls.
214    pthread_setspecific(g_jmpbuf_key, NULL);
215
216    return value;
217  }
218
219  static intptr_t SafeFetchN(intptr_t *adr, intptr_t errValue) {
220
221    sigjmp_buf jb;
222    if (sigsetjmp(jb, 1)) {
223      // we crashed. clean up tls and return default value.
224      pthread_setspecific(g_jmpbuf_key, NULL);
225      return errValue;
226    } else {
227      // preparation phase
228      pthread_setspecific(g_jmpbuf_key, &jb);
229    }
230
231    intptr_t value = errValue;
232    value = *adr;
233
234    // all went well. clean tls.
235    pthread_setspecific(g_jmpbuf_key, NULL);
236
237    return value;
238
239  }
240
241  void generate_initial() {
242    // Generates all stubs and initializes the entry points
243
244    // entry points that exist in all platforms Note: This is code
245    // that could be shared among different platforms - however the
246    // benefit seems to be smaller than the disadvantage of having a
247    // much more complicated generator structure. See also comment in
248    // stubRoutines.hpp.
249
250    StubRoutines::_forward_exception_entry   = ShouldNotCallThisStub();
251    StubRoutines::_call_stub_entry           = (address) call_stub;
252    StubRoutines::_catch_exception_entry     = ShouldNotCallThisStub();
253
254    // atomic calls
255    StubRoutines::_atomic_xchg_entry         = ShouldNotCallThisStub();
256    StubRoutines::_atomic_xchg_ptr_entry     = ShouldNotCallThisStub();
257    StubRoutines::_atomic_cmpxchg_entry      = ShouldNotCallThisStub();
258    StubRoutines::_atomic_cmpxchg_ptr_entry  = ShouldNotCallThisStub();
259    StubRoutines::_atomic_cmpxchg_byte_entry = ShouldNotCallThisStub();
260    StubRoutines::_atomic_cmpxchg_long_entry = ShouldNotCallThisStub();
261    StubRoutines::_atomic_add_entry          = ShouldNotCallThisStub();
262    StubRoutines::_atomic_add_ptr_entry      = ShouldNotCallThisStub();
263    StubRoutines::_fence_entry               = ShouldNotCallThisStub();
264  }
265
266  void generate_all() {
267    // Generates all stubs and initializes the entry points
268
269    // These entry points require SharedInfo::stack0 to be set up in
270    // non-core builds and need to be relocatable, so they each
271    // fabricate a RuntimeStub internally.
272    StubRoutines::_throw_AbstractMethodError_entry =
273      ShouldNotCallThisStub();
274
275    StubRoutines::_throw_NullPointerException_at_call_entry =
276      ShouldNotCallThisStub();
277
278    StubRoutines::_throw_StackOverflowError_entry =
279      ShouldNotCallThisStub();
280
281    // support for verify_oop (must happen after universe_init)
282    StubRoutines::_verify_oop_subroutine_entry =
283      ShouldNotCallThisStub();
284
285    // arraycopy stubs used by compilers
286    generate_arraycopy_stubs();
287
288    // Safefetch stubs.
289    pthread_key_create(&g_jmpbuf_key, NULL);
290    StubRoutines::_safefetch32_entry = CAST_FROM_FN_PTR(address, StubGenerator::SafeFetch32);
291    StubRoutines::_safefetch32_fault_pc = NULL;
292    StubRoutines::_safefetch32_continuation_pc = NULL;
293
294    StubRoutines::_safefetchN_entry = CAST_FROM_FN_PTR(address, StubGenerator::SafeFetchN);
295    StubRoutines::_safefetchN_fault_pc = NULL;
296    StubRoutines::_safefetchN_continuation_pc = NULL;
297  }
298
299 public:
300  StubGenerator(CodeBuffer* code, bool all) : StubCodeGenerator(code) {
301    if (all) {
302      generate_all();
303    } else {
304      generate_initial();
305    }
306  }
307};
308
309void StubGenerator_generate(CodeBuffer* code, bool all) {
310  StubGenerator g(code, all);
311}
312
313EntryFrame *EntryFrame::build(const intptr_t*  parameters,
314                              int              parameter_words,
315                              JavaCallWrapper* call_wrapper,
316                              TRAPS) {
317
318  ZeroStack *stack = ((JavaThread *) THREAD)->zero_stack();
319  stack->overflow_check(header_words + parameter_words, CHECK_NULL);
320
321  stack->push(0); // next_frame, filled in later
322  intptr_t *fp = stack->sp();
323  assert(fp - stack->sp() == next_frame_off, "should be");
324
325  stack->push(ENTRY_FRAME);
326  assert(fp - stack->sp() == frame_type_off, "should be");
327
328  stack->push((intptr_t) call_wrapper);
329  assert(fp - stack->sp() == call_wrapper_off, "should be");
330
331  for (int i = 0; i < parameter_words; i++)
332    stack->push(parameters[i]);
333
334  return (EntryFrame *) fp;
335}
336