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/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "asm_support_arm.S"
/*
* Jni dlsym lookup stub.
*/
.extern artFindNativeMethod
.extern artFindNativeMethodRunnable
ENTRY art_jni_dlsym_lookup_stub
push {r0, r1, r2, r3, lr} @ spill regs
.cfi_adjust_cfa_offset 20
.cfi_rel_offset r0, 0
.cfi_rel_offset r1, 4
.cfi_rel_offset r2, 8
.cfi_rel_offset r3, 12
.cfi_rel_offset lr, 16
sub sp, #12 @ pad stack pointer to align frame
.cfi_adjust_cfa_offset 12
mov r0, rSELF @ pass Thread::Current()
// Call artFindNativeMethod() for normal native and artFindNativeMethodRunnable()
// for @FastNative or @CriticalNative.
ldr ip, [r0, #THREAD_TOP_QUICK_FRAME_OFFSET] // uintptr_t tagged_quick_frame
bic ip, #1 // ArtMethod** sp
ldr ip, [ip] // ArtMethod* method
ldr ip, [ip, #ART_METHOD_ACCESS_FLAGS_OFFSET] // uint32_t access_flags
tst ip, #(ACCESS_FLAGS_METHOD_IS_FAST_NATIVE | ACCESS_FLAGS_METHOD_IS_CRITICAL_NATIVE)
bne .Llookup_stub_fast_native
blx artFindNativeMethod
b .Llookup_stub_continue
.Llookup_stub_fast_native:
blx artFindNativeMethodRunnable
.Llookup_stub_continue:
mov r12, r0 @ save result in r12
add sp, #12 @ restore stack pointer
.cfi_adjust_cfa_offset -12
cbz r0, 1f @ is method code null?
pop {r0, r1, r2, r3, lr} @ restore regs
.cfi_adjust_cfa_offset -20
.cfi_restore r0
.cfi_restore r1
.cfi_restore r2
.cfi_restore r3
.cfi_restore lr
bx r12 @ if non-null, tail call to method's code
1:
pop {r0, r1, r2, r3, pc} @ restore regs and return to caller to handle exception
END art_jni_dlsym_lookup_stub
ENTRY art_jni_dlsym_lookup_critical_stub
// The hidden arg holding the tagged method (bit 0 set means GenericJNI) is r4.
// For Generic JNI we already have a managed frame, so we reuse the art_jni_dlsym_lookup_stub.
tst r4, #1
bne art_jni_dlsym_lookup_stub
// We need to create a GenericJNI managed frame above the stack args.
// GenericJNI frame is similar to SaveRegsAndArgs frame with the native method
// instead of runtime method saved at the bottom. Note that the runtime shall
// not examine the args here, otherwise we would have to move them in registers
// and stack to account for the difference between managed and native ABIs.
SETUP_SAVE_REFS_AND_ARGS_FRAME_REGISTERS_ONLY
// Save the hidden arg as method pointer, r0 in the padding.
// (x0 is an arg in native ABI but not considered an arg in managed ABI.)
strd r4, r0, [sp]
// Call artCriticalNativeOutArgsSize(method)
mov r0, r4 // r0 := method (from hidden arg)
bl artCriticalNativeOutArgsSize
// Check if we have any stack args.
cbnz r0, .Lcritical_has_stack_args
// Without stack args, the frame is fully constructed.
// Place tagged managed sp in Thread::Current()->top_quick_frame.
mov ip, sp
orr ip, #1 // Tag as GenericJNI frame.
str ip, [rSELF, #THREAD_TOP_QUICK_FRAME_OFFSET]
// Call artFindNativeMethodRunnable()
mov r0, rSELF // pass Thread::Current()
bl artFindNativeMethodRunnable
// Store result in scratch reg.
mov ip, r0
// Restore frame.
.cfi_remember_state
ldrd r4, r0, [sp]
RESTORE_SAVE_REFS_AND_ARGS_FRAME
REFRESH_MARKING_REGISTER
// Check for exception.
cmp ip, #0
beq .Lcritical_deliver_exception
// Do the tail call.
bx ip
.cfi_restore_state
.cfi_def_cfa_offset FRAME_SIZE_SAVE_REFS_AND_ARGS
.Lcritical_has_stack_args:
// Move the out args size to a scratch register.
mov ip, r0
// Restore register args as we're about to move stack args.
ldrd r4, r0, [sp]
RESTORE_SAVE_REFS_AND_ARGS_FRAME
// Reserve space for SaveRefsAndArgs frame.
sub sp, #FRAME_SIZE_SAVE_REFS_AND_ARGS
.cfi_adjust_cfa_offset FRAME_SIZE_SAVE_REFS_AND_ARGS
// Save arg regs so that we can use them as temporaries.
push {r0-r3}
.cfi_adjust_cfa_offset 16
// Move out args. For simplicity include the return address at the end.
add r0, sp, #16 // Destination.
add ip, r0, ip // Destination end.
1:
ldrd r2, r3, [r0, #FRAME_SIZE_SAVE_REFS_AND_ARGS]
strd r2, r3, [r0], #8
cmp r0, ip
bne 1b
// Save our LR, load caller's LR and redefine CFI to take ownership of the JNI stub frame.
str lr, [ip, #-__SIZEOF_POINTER__]
mov lr, r3 // The last moved value from the loop above.
.cfi_def_cfa ip, FRAME_SIZE_SAVE_REFS_AND_ARGS
// Restore arg regs.
pop {r0-r3} // No `.cfi_adjust_cfa_offset`, CFA register is currently ip, not sp.
// Re-create the SaveRefsAndArgs frame above the args.
strd r4, r0, [ip] // r0 in the padding as before.
add r4, ip, FRAME_SIZE_SAVE_REFS_AND_ARGS - 40
stmia r4, {r1-r3, r5-r8, r10-r11, lr} @ 10 words of callee saves and args.
.cfi_rel_offset r1, FRAME_SIZE_SAVE_REFS_AND_ARGS - 40 + 0
.cfi_rel_offset r2, FRAME_SIZE_SAVE_REFS_AND_ARGS - 40 + 4
.cfi_rel_offset r3, FRAME_SIZE_SAVE_REFS_AND_ARGS - 40 + 8
.cfi_rel_offset r5, FRAME_SIZE_SAVE_REFS_AND_ARGS - 40 + 12
.cfi_rel_offset r6, FRAME_SIZE_SAVE_REFS_AND_ARGS - 40 + 16
.cfi_rel_offset r7, FRAME_SIZE_SAVE_REFS_AND_ARGS - 40 + 20
.cfi_rel_offset r8, FRAME_SIZE_SAVE_REFS_AND_ARGS - 40 + 24
.cfi_rel_offset r10, FRAME_SIZE_SAVE_REFS_AND_ARGS - 40 + 28
.cfi_rel_offset r11, FRAME_SIZE_SAVE_REFS_AND_ARGS - 40 + 32
.cfi_rel_offset lr, FRAME_SIZE_SAVE_REFS_AND_ARGS - 40 + 36
vstmdb r4!, {s0-s15} @ 16 words of float args.
// Move the frame register to a callee-save register.
mov r11, ip
.cfi_def_cfa_register r11
// Place tagged managed sp in Thread::Current()->top_quick_frame.
orr ip, r11, #1 // Tag as GenericJNI frame.
str ip, [rSELF, #THREAD_TOP_QUICK_FRAME_OFFSET]
// Call artFindNativeMethodRunnable()
mov r0, rSELF // pass Thread::Current()
bl artFindNativeMethodRunnable
// Store result in scratch reg.
mov ip, r0
// Restore the frame. We shall not need the method anymore, so use r4 as scratch register.
mov r4, r11
.cfi_def_cfa_register r4
ldr r0, [r4, #4]
add r11, r4, #(FRAME_SIZE_SAVE_REFS_AND_ARGS - 40 - 64)
vldmia r11!, {s0-s15} @ 16 words of float args.
ldmia r11, {r1-r3, r5-r8, r10-r11, lr} @ 10 words of callee saves and args.
.cfi_restore r1
.cfi_restore r2
.cfi_restore r3
.cfi_restore r5
.cfi_restore r6
.cfi_restore r7
.cfi_restore r8
.cfi_restore r10
.cfi_restore r11
.cfi_restore lr
REFRESH_MARKING_REGISTER
// Check for exception.
cmp ip, #0
beq 3f
// Save arg regs so that we can use them as temporaries.
push {r0-r3} // No `.cfi_adjust_cfa_offset`, CFA register is currently r4, not sp.
// Move stack args to their original place.
mov r0, r4
add r1, sp, #16
2:
ldrd r2, r3, [r0, #-8]!
strd r2, r3, [r0, #FRAME_SIZE_SAVE_REFS_AND_ARGS]
cmp r1, r0
bne 2b
// Replace original return address with caller's return address.
ldr r1, [r4, #(FRAME_SIZE_SAVE_REFS_AND_ARGS - __SIZEOF_POINTER__)]
str lr, [r4, #(FRAME_SIZE_SAVE_REFS_AND_ARGS - __SIZEOF_POINTER__)]
// Restore LR and redefine CFI to release ownership of the JNI stub frame.
.cfi_remember_state
mov lr, r1
.cfi_def_cfa sp, FRAME_SIZE_SAVE_REFS_AND_ARGS + 16
// Restore args
pop {r0-r3}
.cfi_adjust_cfa_offset -16
// Remove the frame reservation.
add sp, #FRAME_SIZE_SAVE_REFS_AND_ARGS
.cfi_adjust_cfa_offset -FRAME_SIZE_SAVE_REFS_AND_ARGS
// Do the tail call.
bx ip
.cfi_restore_state
.cfi_def_cfa r4, FRAME_SIZE_SAVE_REFS_AND_ARGS
3:
// Drop stack args and the SaveRefsAndArgs reservation.
mov sp, r4
add sp, #FRAME_SIZE_SAVE_REFS_AND_ARGS
.cfi_def_cfa sp, 0
.Lcritical_deliver_exception:
// When delivering exception, we check that rSELF was saved but the SaveRefsAndArgs frame does
// not save it, so we cannot use DELIVER_PENDING_EXCEPTION_FRAME_READY with the above frames.
DELIVER_PENDING_EXCEPTION
END art_jni_dlsym_lookup_critical_stub
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