/*
 * 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.h"

#if defined(__APPLE__)
    // Mac OS' as(1) doesn't let you name macro parameters.
    #define MACRO0(macro_name) .macro macro_name
    #define MACRO1(macro_name, macro_arg1) .macro macro_name
    #define MACRO2(macro_name, macro_arg1, macro_args2) .macro macro_name
    #define MACRO3(macro_name, macro_arg1, macro_args2, macro_args3) .macro macro_name
    #define END_MACRO .endmacro

    // Mac OS' as(1) uses $0, $1, and so on for macro arguments, and function names
    // are mangled with an extra underscore prefix. The use of $x for arguments
    // mean that literals need to be represented with $$x in macros.
    #define SYMBOL(name) _ ## name
    #define VAR(name,index) SYMBOL($index)
    #define CALL_MACRO(name,index) $index
    #define LITERAL(value) $value
    #define MACRO_LITERAL(value) $$value
#else
    // Regular gas(1) lets you name macro parameters.
    #define MACRO0(macro_name) .macro macro_name
    #define MACRO1(macro_name, macro_arg1) .macro macro_name macro_arg1
    #define MACRO2(macro_name, macro_arg1, macro_arg2) .macro macro_name macro_arg1, macro_arg2
    #define MACRO3(macro_name, macro_arg1, macro_arg2, macro_arg3) .macro macro_name macro_arg1, macro_arg2, macro_arg3
    #define END_MACRO .endm

    // Regular gas(1) uses \argument_name for macro arguments.
    // We need to turn on alternate macro syntax so we can use & instead or the preprocessor
    // will screw us by inserting a space between the \ and the name. Even in this mode there's
    // no special meaning to $, so literals are still just $x.
    .altmacro
    #define SYMBOL(name) name
    #define VAR(name,index) name&
    #define CALL_MACRO(name,index) name&
    #define LITERAL(value) $value
    #define MACRO_LITERAL(value) $value
#endif

    /* Cache alignment for function entry */
MACRO0(ALIGN_FUNCTION_ENTRY)
    .balign 16
END_MACRO

MACRO1(DEFINE_FUNCTION,c_name)
    .globl VAR(c_name, 0)
    ALIGN_FUNCTION_ENTRY
VAR(c_name, 0):
END_MACRO

    /*
     * Macro that sets up the callee save frame to conform with
     * Runtime::CreateCalleeSaveMethod(kSaveAll)
     */
MACRO0(SETUP_SAVE_ALL_CALLEE_SAVE_FRAME)
    pushl %edi  // Save callee saves (ebx is saved/restored by the upcall)
    pushl %esi
    pushl %ebp
    subl  MACRO_LITERAL(16), %esp  // Grow stack by 4 words, bottom word will hold Method*
END_MACRO

    /*
     * Macro that sets up the callee save frame to conform with
     * Runtime::CreateCalleeSaveMethod(kRefsOnly)
     */
MACRO0(SETUP_REF_ONLY_CALLEE_SAVE_FRAME)
    pushl %edi  // Save callee saves (ebx is saved/restored by the upcall)
    pushl %esi
    pushl %ebp
    subl  MACRO_LITERAL(16), %esp  // Grow stack by 4 words, bottom word will hold Method*
END_MACRO

MACRO0(RESTORE_REF_ONLY_CALLEE_SAVE_FRAME)
    addl MACRO_LITERAL(28), %esp  // Unwind stack up to return address
END_MACRO

    /*
     * Macro that sets up the callee save frame to conform with
     * Runtime::CreateCalleeSaveMethod(kRefsAndArgs)
     */
MACRO0(SETUP_REF_AND_ARG_CALLEE_SAVE_FRAME)
    pushl %edi  // Save callee saves
    pushl %esi
    pushl %ebp
    pushl %ebx  // Save args
    pushl %edx
    pushl %ecx
    pushl %eax  // Align stack, eax will be clobbered by Method*
END_MACRO

MACRO0(RESTORE_REF_AND_ARG_CALLEE_SAVE_FRAME)
    addl MACRO_LITERAL(4), %esp  // Remove padding
    popl %ecx  // Restore args except eax
    popl %edx
    popl %ebx
    popl %ebp  // Restore callee saves
    popl %esi
    popl %edi
END_MACRO

    /*
     * Macro that set calls through to artDeliverPendingExceptionFromCode, where the pending
     * exception is Thread::Current()->exception_.
     */
MACRO0(DELIVER_PENDING_EXCEPTION)
    SETUP_SAVE_ALL_CALLEE_SAVE_FRAME         // save callee saves for throw
    mov %esp, %ecx
    // Outgoing argument set up
    subl  MACRO_LITERAL(8), %esp             // Alignment padding
    pushl %ecx                               // pass SP
    pushl %fs:THREAD_SELF_OFFSET             // pass Thread::Current()
    call SYMBOL(artDeliverPendingExceptionFromCode)  // artDeliverExceptionFromCode(Thread*, SP)
    int3
END_MACRO

MACRO2(NO_ARG_RUNTIME_EXCEPTION, c_name, cxx_name)
    .globl VAR(c_name, 0)
    ALIGN_FUNCTION_ENTRY
VAR(c_name, 0):
    SETUP_SAVE_ALL_CALLEE_SAVE_FRAME  // save all registers as basis for long jump context
    mov %esp, %ecx
    // Outgoing argument set up
    subl  MACRO_LITERAL(8), %esp  // alignment padding
    pushl %ecx                    // pass SP
    pushl %fs:THREAD_SELF_OFFSET  // pass Thread::Current()
    call VAR(cxx_name, 1)         // cxx_name(Thread*, SP)
    int3                          // unreached
END_MACRO

MACRO2(ONE_ARG_RUNTIME_EXCEPTION, c_name, cxx_name)
    .globl VAR(c_name, 0)
    ALIGN_FUNCTION_ENTRY
VAR(c_name, 0):
    SETUP_SAVE_ALL_CALLEE_SAVE_FRAME  // save all registers as basis for long jump context
    mov %esp, %ecx
    // Outgoing argument set up
    pushl %eax                    // alignment padding
    pushl %ecx                    // pass SP
    pushl %fs:THREAD_SELF_OFFSET  // pass Thread::Current()
    pushl %eax                    // pass arg1
    call VAR(cxx_name, 1)         // cxx_name(arg1, Thread*, SP)
    int3                          // unreached
END_MACRO

MACRO2(TWO_ARG_RUNTIME_EXCEPTION, c_name, cxx_name)
    .globl VAR(c_name, 0)
    ALIGN_FUNCTION_ENTRY
VAR(c_name, 0):
    SETUP_SAVE_ALL_CALLEE_SAVE_FRAME  // save all registers as basis for long jump context
    mov %esp, %edx
    // Outgoing argument set up
    pushl %edx                    // pass SP
    pushl %fs:THREAD_SELF_OFFSET  // pass Thread::Current()
    pushl %ecx                    // pass arg2
    pushl %eax                    // pass arg1
    call VAR(cxx_name, 1)         // cxx_name(arg1, arg2, Thread*, SP)
    int3                          // unreached
END_MACRO

    /*
     * Called by managed code to create and deliver a NullPointerException.
     */
NO_ARG_RUNTIME_EXCEPTION art_throw_null_pointer_exception_from_code, artThrowNullPointerExceptionFromCode

    /*
     * Called by managed code to create and deliver an ArithmeticException.
     */
NO_ARG_RUNTIME_EXCEPTION art_throw_div_zero_from_code, artThrowDivZeroFromCode

    /*
     * Called by managed code to create and deliver a StackOverflowError.
     */
NO_ARG_RUNTIME_EXCEPTION art_throw_stack_overflow_from_code, artThrowStackOverflowFromCode

    /*
     * Called by managed code, saves callee saves and then calls artThrowException
     * that will place a mock Method* at the bottom of the stack. Arg1 holds the exception.
     */
ONE_ARG_RUNTIME_EXCEPTION art_deliver_exception_from_code, artDeliverExceptionFromCode

    /*
     * Called by managed code to create and deliver a NoSuchMethodError.
     */
ONE_ARG_RUNTIME_EXCEPTION art_throw_no_such_method_from_code, artThrowNoSuchMethodFromCode

    /*
     * Called by managed code to create and deliver an ArrayIndexOutOfBoundsException. Arg1 holds
     * index, arg2 holds limit.
     */
TWO_ARG_RUNTIME_EXCEPTION art_throw_array_bounds_from_code, artThrowArrayBoundsFromCode

    /*
     * Called by managed code to create and deliver verification errors. Arg1 is kind, arg2 is ref.
     */
TWO_ARG_RUNTIME_EXCEPTION art_throw_verification_error_from_code, artThrowVerificationErrorFromCode

    /*
     * All generated callsites for interface invokes and invocation slow paths will load arguments
     * as usual - except instead of loading arg0/r0 with the target Method*, arg0/r0 will contain
     * the method_idx.  This wrapper will save arg1-arg3, load the caller's Method*, align the
     * stack and call the appropriate C helper.
     * NOTE: "this" is first visible argument of the target, and so can be found in arg1/r1.
     *
     * The helper will attempt to locate the target and return a 64-bit result in r0/r1 consisting
     * of the target Method* in r0 and method->code_ in r1.
     *
     * If unsuccessful, the helper will return NULL/NULL. There will bea pending exception in the
     * thread and we branch to another stub to deliver it.
     *
     * On success this wrapper will restore arguments and *jump* to the target, leaving the lr
     * pointing back to the original caller.
     */
MACRO2(INVOKE_TRAMPOLINE, c_name, cxx_name)
    .globl VAR(c_name, 0)
    ALIGN_FUNCTION_ENTRY
VAR(c_name, 0):
    // Set up the callee save frame to conform with Runtime::CreateCalleeSaveMethod(kRefsAndArgs)
    // return address
    pushl %edi
    pushl %esi
    pushl %ebp
    pushl %ebx
    pushl %edx
    pushl %ecx
    pushl %eax  // <-- callee save Method* to go here
    movl %esp, %edx  // remember SP
    // Outgoing argument set up
    subl MACRO_LITERAL(12), %esp  // alignment padding
    pushl %edx                    // pass SP
    pushl %fs:THREAD_SELF_OFFSET  // pass Thread::Current()
    pushl 32(%edx)                // pass caller Method*
    pushl %ecx                    // pass arg2
    pushl %eax                    // pass arg1
    call VAR(cxx_name, 1)         // cxx_name(arg1, arg2, arg3, Thread*, SP)
    movl %edx, %edi               // save code pointer in EDI
    addl MACRO_LITERAL(36), %esp  // Pop arguments skip eax
    popl %ecx                     // Restore args
    popl %edx
    popl %ebx
    popl %ebp  // Restore callee saves.
    popl %esi
    // Swap EDI callee save with code pointer.
    xchgl %edi, (%esp)
    testl %eax, %eax              // Branch forward if exception pending.
    jz    1f
    // Tail call to intended method.
    ret
1:
    DELIVER_PENDING_EXCEPTION
END_MACRO

INVOKE_TRAMPOLINE art_invoke_interface_trampoline, artInvokeInterfaceTrampoline
INVOKE_TRAMPOLINE art_invoke_interface_trampoline_with_access_check, artInvokeInterfaceTrampolineWithAccessCheck

INVOKE_TRAMPOLINE art_invoke_static_trampoline_with_access_check, artInvokeStaticTrampolineWithAccessCheck
INVOKE_TRAMPOLINE art_invoke_direct_trampoline_with_access_check, artInvokeDirectTrampolineWithAccessCheck
INVOKE_TRAMPOLINE art_invoke_super_trampoline_with_access_check, artInvokeSuperTrampolineWithAccessCheck
INVOKE_TRAMPOLINE art_invoke_virtual_trampoline_with_access_check, artInvokeVirtualTrampolineWithAccessCheck

MACRO3(NO_ARG_DOWNCALL, c_name, cxx_name, return_macro)
    .globl VAR(c_name, 0)
    ALIGN_FUNCTION_ENTRY
VAR(c_name, 0):
    SETUP_REF_ONLY_CALLEE_SAVE_FRAME  // save ref containing registers for GC
    mov %esp, %edx                // remember SP
    // Outgoing argument set up
    subl MACRO_LITERAL(8), %esp   // push padding
    pushl %edx                    // pass SP
    pushl %fs:THREAD_SELF_OFFSET  // pass Thread::Current()
    call VAR(cxx_name, 1)         // cxx_name(Thread*, SP)
    addl MACRO_LITERAL(16), %esp  // pop arguments
    RESTORE_REF_ONLY_CALLEE_SAVE_FRAME  // restore frame up to return address
    CALL_MACRO(return_macro, 2)   // return or deliver exception
END_MACRO

MACRO3(ONE_ARG_DOWNCALL, c_name, cxx_name, return_macro)
    .globl VAR(c_name, 0)
    ALIGN_FUNCTION_ENTRY
VAR(c_name, 0):
    SETUP_REF_ONLY_CALLEE_SAVE_FRAME  // save ref containing registers for GC
    mov %esp, %edx                // remember SP
    // Outgoing argument set up
    pushl %eax                    // push padding
    pushl %edx                    // pass SP
    pushl %fs:THREAD_SELF_OFFSET  // pass Thread::Current()
    pushl %eax                    // pass arg1
    call VAR(cxx_name, 1)         // cxx_name(arg1, Thread*, SP)
    addl MACRO_LITERAL(16), %esp  // pop arguments
    RESTORE_REF_ONLY_CALLEE_SAVE_FRAME  // restore frame up to return address
    CALL_MACRO(return_macro, 2)   // return or deliver exception
END_MACRO

MACRO3(TWO_ARG_DOWNCALL, c_name, cxx_name, return_macro)
    .globl VAR(c_name, 0)
    ALIGN_FUNCTION_ENTRY
VAR(c_name, 0):
    SETUP_REF_ONLY_CALLEE_SAVE_FRAME  // save ref containing registers for GC
    mov %esp, %edx                // remember SP
    // Outgoing argument set up
    pushl %edx                    // pass SP
    pushl %fs:THREAD_SELF_OFFSET  // pass Thread::Current()
    pushl %ecx                    // pass arg2
    pushl %eax                    // pass arg1
    call VAR(cxx_name, 1)         // cxx_name(arg1, arg2, Thread*, SP)
    addl MACRO_LITERAL(16), %esp  // pop arguments
    RESTORE_REF_ONLY_CALLEE_SAVE_FRAME  // restore frame up to return address
    CALL_MACRO(return_macro, 2)   // return or deliver exception
END_MACRO

MACRO3(THREE_ARG_DOWNCALL, c_name, cxx_name, return_macro)
    .globl VAR(c_name, 0)
    ALIGN_FUNCTION_ENTRY
VAR(c_name, 0):
    SETUP_REF_ONLY_CALLEE_SAVE_FRAME  // save ref containing registers for GC
    mov %esp, %ebx                // remember SP
    // Outgoing argument set up
    subl MACRO_LITERAL(12), %esp  // alignment padding
    pushl %ebx                    // pass SP
    pushl %fs:THREAD_SELF_OFFSET  // pass Thread::Current()
    pushl %edx                    // pass arg3
    pushl %ecx                    // pass arg2
    pushl %eax                    // pass arg1
    call VAR(cxx_name, 1)         // cxx_name(arg1, arg2, arg3, Thread*, SP)
    addl MACRO_LITERAL(32), %esp  // pop arguments
    RESTORE_REF_ONLY_CALLEE_SAVE_FRAME  // restore frame up to return address
    CALL_MACRO(return_macro, 2)   // return or deliver exception
END_MACRO

MACRO0(RETURN_IF_EAX_NOT_ZERO)
    testl %eax, %eax               // eax == 0 ?
    jz  1f                         // if eax == 0 goto 1
    ret                            // return
1:                                 // deliver exception on current thread
    DELIVER_PENDING_EXCEPTION
END_MACRO

MACRO0(RETURN_IF_EAX_ZERO)
    testl %eax, %eax               // eax == 0 ?
    jnz  1f                        // if eax != 0 goto 1
    ret                            // return
1:                                 // deliver exception on current thread
    DELIVER_PENDING_EXCEPTION
END_MACRO

TWO_ARG_DOWNCALL art_alloc_object_from_code, artAllocObjectFromCode, RETURN_IF_EAX_NOT_ZERO
TWO_ARG_DOWNCALL art_alloc_object_from_code_with_access_check, artAllocObjectFromCodeWithAccessCheck, RETURN_IF_EAX_NOT_ZERO
THREE_ARG_DOWNCALL art_alloc_array_from_code, artAllocArrayFromCode, RETURN_IF_EAX_NOT_ZERO
THREE_ARG_DOWNCALL art_alloc_array_from_code_with_access_check, artAllocArrayFromCodeWithAccessCheck, RETURN_IF_EAX_NOT_ZERO
THREE_ARG_DOWNCALL art_check_and_alloc_array_from_code, artCheckAndAllocArrayFromCode, RETURN_IF_EAX_NOT_ZERO
THREE_ARG_DOWNCALL art_check_and_alloc_array_from_code_with_access_check, artCheckAndAllocArrayFromCodeWithAccessCheck, RETURN_IF_EAX_NOT_ZERO

TWO_ARG_DOWNCALL art_resolve_string_from_code, artResolveStringFromCode, RETURN_IF_EAX_NOT_ZERO
TWO_ARG_DOWNCALL art_initialize_static_storage_from_code, artInitializeStaticStorageFromCode, RETURN_IF_EAX_NOT_ZERO
TWO_ARG_DOWNCALL art_initialize_type_from_code, artInitializeTypeFromCode, RETURN_IF_EAX_NOT_ZERO
TWO_ARG_DOWNCALL art_initialize_type_and_verify_access_from_code, artInitializeTypeAndVerifyAccessFromCode, RETURN_IF_EAX_NOT_ZERO

ONE_ARG_DOWNCALL art_lock_object_from_code, artLockObjectFromCode, ret
ONE_ARG_DOWNCALL art_unlock_object_from_code, artUnlockObjectFromCode, RETURN_IF_EAX_ZERO

TWO_ARG_DOWNCALL art_handle_fill_data_from_code, artHandleFillArrayDataFromCode, RETURN_IF_EAX_ZERO

DEFINE_FUNCTION art_is_assignable_from_code
    pushl %eax                    // alignment padding
    pushl %ecx                    // pass arg2
    pushl %eax                    // pass arg1
    call SYMBOL(artIsAssignableFromCode)  // (Class* a, Class* b, Thread*, SP)
    addl LITERAL(12), %esp        // pop arguments
    ret

DEFINE_FUNCTION art_memcpy
    pushl %edx                    // pass arg3
    pushl %ecx                    // pass arg2
    pushl %eax                    // pass arg1
    call SYMBOL(memcpy)           // (void*, const void*, size_t)
    addl LITERAL(12), %esp        // pop arguments
    ret

TWO_ARG_DOWNCALL art_check_cast_from_code, artCheckCastFromCode, RETURN_IF_EAX_ZERO
TWO_ARG_DOWNCALL art_can_put_array_element_from_code, artCanPutArrayElementFromCode, RETURN_IF_EAX_ZERO

NO_ARG_DOWNCALL art_test_suspend, artTestSuspendFromCode, ret

DEFINE_FUNCTION art_l2d_from_code
    pushl %eax                    // alignment padding
    pushl %ecx                    // pass arg2
    pushl %eax                    // pass arg1
    call SYMBOL(art_l2d) // (jlong a, Thread*, SP)
    fstpl (%esp)                  // get return value
    movsd (%esp), %xmm0           // place into %xmm0
    addl LITERAL(12), %esp        // pop arguments
    ret

DEFINE_FUNCTION art_l2f_from_code
    pushl %eax                    // alignment padding
    pushl %ecx                    // pass arg2
    pushl %eax                    // pass arg1
    call SYMBOL(art_l2f) // (jlong a, Thread*, SP)
    fstp  (%esp)                  // get return value
    movss (%esp), %xmm0           // place into %xmm0
    addl LITERAL(12), %esp        // pop arguments
    ret

DEFINE_FUNCTION art_d2l_from_code
    pushl %eax                    // alignment padding
    pushl %ecx                    // pass arg2
    pushl %eax                    // pass arg1
    call SYMBOL(art_d2l) // (jdouble a, Thread*, SP)
    addl LITERAL(12), %esp        // pop arguments
    ret

DEFINE_FUNCTION art_f2l_from_code
    subl LITERAL(8), %esp         // alignment padding
    pushl %eax                    // pass arg1
    call SYMBOL(art_f2l) // (jfloat a, Thread*, SP)
    addl LITERAL(12), %esp        // pop arguments
    ret

DEFINE_FUNCTION art_idivmod_from_code
    cmpl LITERAL(0x80000000), %eax
    je check_arg2  // special case
args_ok:
    cdq         // edx:eax = sign extend eax
    idiv %ecx   // (edx,eax) = (edx:eax % ecx, edx:eax / ecx)
    ret
check_arg2:
    cmpl LITERAL(-1), %ecx
    jne args_ok
    xorl %edx, %edx
    ret         // eax already holds min int

DEFINE_FUNCTION art_ldiv_from_code
    subl LITERAL(12), %esp        // alignment padding
    pushl %ebx                    // pass arg4
    pushl %edx                    // pass arg3
    pushl %ecx                    // pass arg2
    pushl %eax                    // pass arg1
    call SYMBOL(artLdivFromCode)  // (jlong a, jlong b, Thread*, SP)
    addl LITERAL(28), %esp        // pop arguments
    ret

DEFINE_FUNCTION art_ldivmod_from_code
    subl LITERAL(12), %esp        // alignment padding
    pushl %ebx                    // pass arg4
    pushl %edx                    // pass arg3
    pushl %ecx                    // pass arg2
    pushl %eax                    // pass arg1
    call SYMBOL(artLdivmodFromCode) // (jlong a, jlong b, Thread*, SP)
    addl LITERAL(28), %esp        // pop arguments
    ret

DEFINE_FUNCTION art_lmul_from_code
    subl LITERAL(12), %esp        // alignment padding
    pushl %ebx                    // pass arg4
    pushl %edx                    // pass arg3
    pushl %ecx                    // pass arg2
    pushl %eax                    // pass arg1
    call SYMBOL(artLmulFromCode)  // (jlong a, jlong b, Thread*, SP)
    addl LITERAL(28), %esp        // pop arguments
    ret

DEFINE_FUNCTION art_lshl_from_code
    // ecx:eax << edx
    xchg %edx, %ecx
    shld %cl,%eax,%edx
    shl  %cl,%eax
    test LITERAL(32), %cl
    jz  1f
    mov %eax, %edx
    xor %eax, %eax
1:
    ret

DEFINE_FUNCTION art_lshr_from_code
    // ecx:eax >> edx
    xchg %edx, %ecx
    shrd %cl,%edx,%eax
    sar  %cl,%edx
    test LITERAL(32),%cl
    jz  1f
    mov %edx, %eax
    sar LITERAL(31), %edx
1:
    ret

DEFINE_FUNCTION art_lushr_from_code
    // ecx:eax >>> edx
    xchg %edx, %ecx
    shrd %cl,%edx,%eax
    shr  %cl,%edx
    test LITERAL(32),%cl
    jz  1f
    mov %edx, %eax
    xor %edx, %edx
1:
    ret

MACRO1(UNIMPLEMENTED,name)
    .globl VAR(name, 0)
    ALIGN_FUNCTION_ENTRY
VAR(name, 0):
    int3
END_MACRO

    // TODO: implement these!
UNIMPLEMENTED art_proxy_invoke_handler
UNIMPLEMENTED art_update_debugger
UNIMPLEMENTED art_set32_instance_from_code
UNIMPLEMENTED art_set64_instance_from_code
UNIMPLEMENTED art_set_obj_instance_from_code
UNIMPLEMENTED art_get32_instance_from_code
UNIMPLEMENTED art_get64_instance_from_code
UNIMPLEMENTED art_get_obj_instance_from_code
UNIMPLEMENTED art_set32_static_from_code
UNIMPLEMENTED art_set64_static_from_code
UNIMPLEMENTED art_set_obj_static_from_code
UNIMPLEMENTED art_get32_static_from_code
UNIMPLEMENTED art_get64_static_from_code
UNIMPLEMENTED art_get_obj_static_from_code
UNIMPLEMENTED art_indexof
UNIMPLEMENTED art_memcmp16
UNIMPLEMENTED art_string_compareto