xref: /aosp_15_r20/art/runtime/arch/riscv64/native_entrypoints_riscv64.S (revision 795d594fd825385562da6b089ea9b2033f3abf5a)
1/*
2 * Copyright (C) 2024 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include "asm_support_riscv64.S"
18#include "interpreter/cfi_asm_support.h"
19
20/*
21 * This file contains all native entrypoints that are called using the native ABI and do not
22 * transition to the quick ABI. For example: the switch interpreter (using the native ABI) directly
23 * calls ExecuteSwitchImplAsm and this code will always return back to the switch interpreter,
24 * again using the native ABI. Because of this behaviour ExecuteSwitchImplAsm should be included in
25 * this file. This is done so these native entrypoints can be compiled independently to quick
26 * entrypoints for cases when the kRuntimeISA and kRuntimeQuickCodeISA do not match.
27 *
28 * See comment on StackType (thread.h) for definitions and examples of quick ABI/code and
29 * native ABI/code.
30 */
31
32// Wrap ExecuteSwitchImpl in assembly method which specifies DEX PC for unwinding.
33//  Argument 0: a0: The context pointer for ExecuteSwitchImpl.
34//  Argument 1: a1: Pointer to the templated ExecuteSwitchImpl to call.
35//  Argument 2: a2: The value of DEX PC (memory address of the methods bytecode).
36ENTRY ExecuteSwitchImplAsm
37    INCREASE_FRAME 16
38    SAVE_GPR s1, 0
39    SAVE_GPR ra, 8
40
41    mv s1, a2   // s1 = DEX PC
42    CFI_DEFINE_DEX_PC_WITH_OFFSET(0 /* a0 */, 9 /* s1, a.k.a. x9 */, 0)
43    jalr a1     // Call the wrapped method.
44
45    RESTORE_GPR s1, 0
46    RESTORE_GPR ra, 8
47    DECREASE_FRAME 16
48    ret
49END ExecuteSwitchImplAsm
50
51// JNI dlsym lookup stub.
52.extern artFindNativeMethod
53.extern artFindNativeMethodRunnable
54ENTRY art_jni_dlsym_lookup_stub
55    SAVE_ALL_ARGS_INCREASE_FRAME 2*8
56    SAVE_GPR fp, (ALL_ARGS_SIZE + 0)
57    SAVE_GPR ra, (ALL_ARGS_SIZE + 8)
58    add  fp, sp, ALL_ARGS_SIZE
59
60    // Call artFindNativeMethod for normal native.
61    // Call artFindNativeMethodRunnable for @FastNative or @CriticalNative.
62    // Both functions have a single argument: Thread::Current() in a0.
63    mv   a0, xSELF
64    ld   t0, THREAD_TOP_QUICK_FRAME_OFFSET(a0)   // uintptr_t tagged_quick_frame
65    andi t0, t0, ~TAGGED_JNI_SP_MASK             // ArtMethod** sp
66    ld   t0, (t0)                                // ArtMethod* method
67    lw   t0, ART_METHOD_ACCESS_FLAGS_OFFSET(t0)  // uint32_t access_flags
68    li   t1, (ACCESS_FLAGS_METHOD_IS_FAST_NATIVE | ACCESS_FLAGS_METHOD_IS_CRITICAL_NATIVE)
69    and  t0, t0, t1
70    bnez t0, .Llookup_stub_fast_or_critical_native
71    call artFindNativeMethod
72    j    .Llookup_stub_continue
73
74.Llookup_stub_fast_or_critical_native:
75    call  artFindNativeMethodRunnable
76
77.Llookup_stub_continue:
78    mv    t0, a0  // store result in a temp reg.
79    RESTORE_GPR fp, (ALL_ARGS_SIZE + 0)
80    RESTORE_GPR ra, (ALL_ARGS_SIZE + 8)
81    RESTORE_ALL_ARGS_DECREASE_FRAME 2*8
82
83    beqz  t0, 1f  // is method code null?
84    jr    t0      // if non-null, tail call to method code.
851:
86    ret           // restore regs and return to caller to handle exception.
87END art_jni_dlsym_lookup_stub
88