xref: /aosp_15_r20/art/runtime/arch/arm/native_entrypoints_arm.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_arm.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: r0: The context pointer for ExecuteSwitchImpl.
34//  Argument 1: r1: Pointer to the templated ExecuteSwitchImpl to call.
35//  Argument 2: r2: The value of DEX PC (memory address of the methods bytecode).
36ENTRY ExecuteSwitchImplAsm
37    push {r4, lr}                                 // 2 words of callee saves.
38    .cfi_adjust_cfa_offset 8
39    .cfi_rel_offset r4, 0
40    .cfi_rel_offset lr, 4
41    mov r4, r2                                    // r4 = DEX PC
42    CFI_DEFINE_DEX_PC_WITH_OFFSET(0 /* r0 */, 4 /* r4 */, 0)
43    blx r1                                        // Call the wrapped method.
44    pop {r4, pc}
45END ExecuteSwitchImplAsm
46
47    /*
48     * Jni dlsym lookup stub.
49     */
50    .extern artFindNativeMethod
51    .extern artFindNativeMethodRunnable
52ENTRY art_jni_dlsym_lookup_stub
53    push   {r0, r1, r2, r3, lr}           @ spill regs
54    .cfi_adjust_cfa_offset 20
55    .cfi_rel_offset lr, 16
56    sub    sp, #12                        @ pad stack pointer to align frame
57    .cfi_adjust_cfa_offset 12
58
59    mov    r0, rSELF                      @ pass Thread::Current()
60    // Call artFindNativeMethod() for normal native and artFindNativeMethodRunnable()
61    // for @FastNative or @CriticalNative.
62    ldr    ip, [r0, #THREAD_TOP_QUICK_FRAME_OFFSET]   // uintptr_t tagged_quick_frame
63    bic    ip, #TAGGED_JNI_SP_MASK                    // ArtMethod** sp
64    ldr    ip, [ip]                                   // ArtMethod* method
65    ldr    ip, [ip, #ART_METHOD_ACCESS_FLAGS_OFFSET]  // uint32_t access_flags
66    tst    ip, #(ACCESS_FLAGS_METHOD_IS_FAST_NATIVE | ACCESS_FLAGS_METHOD_IS_CRITICAL_NATIVE)
67    bne    .Llookup_stub_fast_or_critical_native
68    blx    artFindNativeMethod
69    b      .Llookup_stub_continue
70.Llookup_stub_fast_or_critical_native:
71    blx    artFindNativeMethodRunnable
72.Llookup_stub_continue:
73    mov    r12, r0                        @ save result in r12
74
75    add    sp, #12                        @ restore stack pointer
76    .cfi_adjust_cfa_offset -12
77    CFI_REMEMBER_STATE
78    cbz    r0, 1f                         @ is method code null?
79    pop    {r0, r1, r2, r3, lr}           @ restore regs
80    .cfi_adjust_cfa_offset -20
81    .cfi_restore lr
82    bx     r12                            @ if non-null, tail call to method's code
831:
84    CFI_RESTORE_STATE_AND_DEF_CFA sp, 20
85    pop    {r0, r1, r2, r3, pc}           @ restore regs and return to caller to handle exception
86END art_jni_dlsym_lookup_stub
87
88