/*
 * 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_x86_64.S"

// For x86, the CFA is esp+4, the address above the pushed return address on the stack.

    /*
     * Macro that sets up the callee save frame to conform with
     * Runtime::CreateCalleeSaveMethod(kSaveAll)
     */
MACRO0(SETUP_SAVE_ALL_CALLEE_SAVE_FRAME)
    // R10 := Runtime::Current()
    movq _ZN3art7Runtime9instance_E@GOTPCREL(%rip), %r10
    movq (%r10), %r10
    // Save callee save registers to agree with core spills bitmap.
    PUSH r15  // Callee save.
    PUSH r14  // Callee save.
    PUSH r13  // Callee save.
    PUSH r12  // Callee save.
    PUSH rbp  // Callee save.
    PUSH rbx  // Callee save.
    subq MACRO_LITERAL(8), %rsp  // Space for Method* (also aligns the frame).
    CFI_ADJUST_CFA_OFFSET(8)
    // R10 := ArtMethod* for save all callee save frame method.
    movq RUNTIME_SAVE_ALL_CALLEE_SAVE_FRAME_OFFSET(%r10), %r10
    // Store ArtMethod* to bottom of stack.
    movq %r10, 0(%rsp)

    // Ugly compile-time check, but we only have the preprocessor.
    // Last +8: implicit return address pushed on stack when caller made call.
#if (FRAME_SIZE_SAVE_ALL_CALLEE_SAVE != 6*8 + 8 + 8)
#error "SAVE_ALL_CALLEE_SAVE_FRAME(X86_64) size not as expected."
#endif
END_MACRO

    /*
     * Macro that sets up the callee save frame to conform with
     * Runtime::CreateCalleeSaveMethod(kRefsOnly)
     */
MACRO0(SETUP_REF_ONLY_CALLEE_SAVE_FRAME)
    // R10 := Runtime::Current()
    movq _ZN3art7Runtime9instance_E@GOTPCREL(%rip), %r10
    movq (%r10), %r10
    // Save callee and GPR args, mixed together to agree with core spills bitmap.
    PUSH r15  // Callee save.
    PUSH r14  // Callee save.
    PUSH r13  // Callee save.
    PUSH r12  // Callee save.
    PUSH rbp  // Callee save.
    PUSH rbx  // Callee save.
    subq MACRO_LITERAL(8), %rsp  // Space for Method* (also aligns the frame).
    CFI_ADJUST_CFA_OFFSET(8)
    // R10 := ArtMethod* for refs only callee save frame method.
    movq RUNTIME_REFS_ONLY_CALLEE_SAVE_FRAME_OFFSET(%r10), %r10
    // Store ArtMethod* to bottom of stack.
    movq %r10, 0(%rsp)

    // Ugly compile-time check, but we only have the preprocessor.
    // Last +8: implicit return address pushed on stack when caller made call.
#if (FRAME_SIZE_REFS_ONLY_CALLEE_SAVE != 6*8 + 8 + 8)
#error "REFS_ONLY_CALLEE_SAVE_FRAME(X86_64) size not as expected."
#endif
END_MACRO

MACRO0(RESTORE_REF_ONLY_CALLEE_SAVE_FRAME)
    addq MACRO_LITERAL(8), %rsp
    CFI_ADJUST_CFA_OFFSET(-8)
    // TODO: optimize by not restoring callee-saves restored by the ABI
    POP rbx
    POP rbp
    POP r12
    POP r13
    POP r14
    POP r15
END_MACRO

    /*
     * Macro that sets up the callee save frame to conform with
     * Runtime::CreateCalleeSaveMethod(kRefsAndArgs)
     */
MACRO0(SETUP_REF_AND_ARGS_CALLEE_SAVE_FRAME)
    // R10 := Runtime::Current()
    movq _ZN3art7Runtime9instance_E@GOTPCREL(%rip), %r10
    movq (%r10), %r10
    // Save callee and GPR args, mixed together to agree with core spills bitmap.
    PUSH r15  // Callee save.
    PUSH r14  // Callee save.
    PUSH r13  // Callee save.
    PUSH r12  // Callee save.
    PUSH r9   // Quick arg 5.
    PUSH r8   // Quick arg 4.
    PUSH rsi  // Quick arg 1.
    PUSH rbp  // Callee save.
    PUSH rbx  // Callee save.
    PUSH rdx  // Quick arg 2.
    PUSH rcx  // Quick arg 3.
    // Create space for FPR args and create 2 slots, 1 of padding and 1 for the ArtMethod*.
    subq MACRO_LITERAL(80), %rsp
    CFI_ADJUST_CFA_OFFSET(80)
    // R10 := ArtMethod* for ref and args callee save frame method.
    movq RUNTIME_REF_AND_ARGS_CALLEE_SAVE_FRAME_OFFSET(%r10), %r10
    // Save FPRs.
    movq %xmm0, 16(%rsp)
    movq %xmm1, 24(%rsp)
    movq %xmm2, 32(%rsp)
    movq %xmm3, 40(%rsp)
    movq %xmm4, 48(%rsp)
    movq %xmm5, 56(%rsp)
    movq %xmm6, 64(%rsp)
    movq %xmm7, 72(%rsp)
    // Store ArtMethod* to bottom of stack.
    movq %r10, 0(%rsp)

    // Ugly compile-time check, but we only have the preprocessor.
    // Last +8: implicit return address pushed on stack when caller made call.
#if (FRAME_SIZE_REFS_AND_ARGS_CALLEE_SAVE != 11*8 + 80 + 8)
#error "REFS_AND_ARGS_CALLEE_SAVE_FRAME(X86_64) size not as expected."
#endif
END_MACRO

MACRO0(RESTORE_REF_AND_ARGS_CALLEE_SAVE_FRAME)
    // Restore FPRs.
    movq 16(%rsp), %xmm0
    movq 24(%rsp), %xmm1
    movq 32(%rsp), %xmm2
    movq 40(%rsp), %xmm3
    movq 48(%rsp), %xmm4
    movq 56(%rsp), %xmm5
    movq 64(%rsp), %xmm6
    movq 72(%rsp), %xmm7
    addq MACRO_LITERAL(80), %rsp
    CFI_ADJUST_CFA_OFFSET(-80)
    // Restore callee and GPR args, mixed together to agree with core spills bitmap.
    POP rcx
    POP rdx
    POP rbx
    POP rbp
    POP rsi
    POP r8
    POP r9
    POP r12
    POP r13
    POP r14
    POP r15
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
    // (Thread*, SP) setup
    movq %gs:THREAD_SELF_OFFSET, %rdi
    movq %rsp, %rsi
    call PLT_SYMBOL(artDeliverPendingExceptionFromCode)  // artDeliverPendingExceptionFromCode(Thread*, SP)
    UNREACHABLE
END_MACRO

MACRO2(NO_ARG_RUNTIME_EXCEPTION, c_name, cxx_name)
    DEFINE_FUNCTION VAR(c_name, 0)
    SETUP_SAVE_ALL_CALLEE_SAVE_FRAME  // save all registers as basis for long jump context
    // Outgoing argument set up
    movq %rsp, %rsi                    // pass SP
    movq %gs:THREAD_SELF_OFFSET, %rdi  // pass Thread::Current()
    call PLT_VAR(cxx_name, 1)     // cxx_name(Thread*, SP)
    UNREACHABLE
    END_FUNCTION VAR(c_name, 0)
END_MACRO

MACRO2(ONE_ARG_RUNTIME_EXCEPTION, c_name, cxx_name)
    DEFINE_FUNCTION VAR(c_name, 0)
    SETUP_SAVE_ALL_CALLEE_SAVE_FRAME  // save all registers as basis for long jump context
    // Outgoing argument set up
    movq %rsp, %rdx                    // pass SP
    movq %gs:THREAD_SELF_OFFSET, %rsi  // pass Thread::Current()
    call PLT_VAR(cxx_name, 1)     // cxx_name(arg1, Thread*, SP)
    UNREACHABLE
    END_FUNCTION VAR(c_name, 0)
END_MACRO

MACRO2(TWO_ARG_RUNTIME_EXCEPTION, c_name, cxx_name)
    DEFINE_FUNCTION VAR(c_name, 0)
    SETUP_SAVE_ALL_CALLEE_SAVE_FRAME  // save all registers as basis for long jump context
    // Outgoing argument set up
    movq %rsp, %rcx                    // pass SP
    movq %gs:THREAD_SELF_OFFSET, %rdx  // pass Thread::Current()
    call PLT_VAR(cxx_name, 1)     // cxx_name(Thread*, SP)
    UNREACHABLE
    END_FUNCTION VAR(c_name, 0)
END_MACRO

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

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

    /*
     * Called by managed code to create and deliver a StackOverflowError.
     */
NO_ARG_RUNTIME_EXCEPTION art_quick_throw_stack_overflow, 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_quick_deliver_exception, artDeliverExceptionFromCode

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

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

    /*
     * All generated callsites for interface invokes and invocation slow paths will load arguments
     * as usual - except instead of loading arg0/rdi with the target Method*, arg0/rdi 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/rsi.
     *
     * The helper will attempt to locate the target and return a 128-bit result in rax/rdx consisting
     * of the target Method* in rax and method->code_ in rdx.
     *
     * If unsuccessful, the helper will return NULL/????. There will be a 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 return
     * location on the stack.
     *
     * Adapted from x86 code.
     */
MACRO2(INVOKE_TRAMPOLINE, c_name, cxx_name)
    DEFINE_FUNCTION VAR(c_name, 0)
    SETUP_REF_AND_ARGS_CALLEE_SAVE_FRAME  // save callee saves in case allocation triggers GC
    // Helper signature is always
    // (method_idx, *this_object, *caller_method, *self, sp)

    movq FRAME_SIZE_REFS_AND_ARGS_CALLEE_SAVE(%rsp), %rdx  // pass caller Method*
    movq %gs:THREAD_SELF_OFFSET, %rcx                      // pass Thread
    movq %rsp, %r8                                         // pass SP

    call PLT_VAR(cxx_name, 1)                   // cxx_name(arg1, arg2, caller method*, Thread*, SP)
                                                           // save the code pointer
    movq %rax, %rdi
    movq %rdx, %rax
    RESTORE_REF_AND_ARGS_CALLEE_SAVE_FRAME

    testq %rdi, %rdi
    jz 1f

    // Tail call to intended method.
    jmp *%rax
1:
    DELIVER_PENDING_EXCEPTION
    END_FUNCTION VAR(c_name, 0)
END_MACRO

INVOKE_TRAMPOLINE art_quick_invoke_interface_trampoline, artInvokeInterfaceTrampoline
INVOKE_TRAMPOLINE art_quick_invoke_interface_trampoline_with_access_check, artInvokeInterfaceTrampolineWithAccessCheck

INVOKE_TRAMPOLINE art_quick_invoke_static_trampoline_with_access_check, artInvokeStaticTrampolineWithAccessCheck
INVOKE_TRAMPOLINE art_quick_invoke_direct_trampoline_with_access_check, artInvokeDirectTrampolineWithAccessCheck
INVOKE_TRAMPOLINE art_quick_invoke_super_trampoline_with_access_check, artInvokeSuperTrampolineWithAccessCheck
INVOKE_TRAMPOLINE art_quick_invoke_virtual_trampoline_with_access_check, artInvokeVirtualTrampolineWithAccessCheck


    /*
     * Helper for quick invocation stub to set up XMM registers. Assumes r10 == shorty,
     * r11 == arg_array. Clobbers r10, r11 and al. Branches to xmm_setup_finished if it encounters
     * the end of the shorty.
     */
MACRO2(LOOP_OVER_SHORTY_LOADING_XMMS, xmm_reg, finished)
1: // LOOP
    movb (%r10), %al              // al := *shorty
    addq MACRO_LITERAL(1), %r10   // shorty++
    cmpb MACRO_LITERAL(0), %al    // if (al == '\0') goto xmm_setup_finished
    je VAR(finished, 1)
    cmpb MACRO_LITERAL(68), %al   // if (al == 'D') goto FOUND_DOUBLE
    je 2f
    cmpb MACRO_LITERAL(70), %al   // if (al == 'F') goto FOUND_FLOAT
    je 3f
    addq MACRO_LITERAL(4), %r11   // arg_array++
    //  Handle extra space in arg array taken by a long.
    cmpb MACRO_LITERAL(74), %al   // if (al != 'J') goto LOOP
    jne 1b
    addq MACRO_LITERAL(4), %r11   // arg_array++
    jmp 1b                        // goto LOOP
2:  // FOUND_DOUBLE
    movsd (%r11), REG_VAR(xmm_reg, 0)
    addq MACRO_LITERAL(8), %r11   // arg_array+=2
    jmp 4f
3:  // FOUND_FLOAT
    movss (%r11), REG_VAR(xmm_reg, 0)
    addq MACRO_LITERAL(4), %r11   // arg_array++
4:
END_MACRO

    /*
     * Helper for quick invocation stub to set up GPR registers. Assumes r10 == shorty,
     * r11 == arg_array. Clobbers r10, r11 and al. Branches to gpr_setup_finished if it encounters
     * the end of the shorty.
     */
MACRO3(LOOP_OVER_SHORTY_LOADING_GPRS, gpr_reg64, gpr_reg32, finished)
1: // LOOP
    movb (%r10), %al              // al := *shorty
    addq MACRO_LITERAL(1), %r10   // shorty++
    cmpb MACRO_LITERAL(0), %al    // if (al == '\0') goto gpr_setup_finished
    je  VAR(finished, 2)
    cmpb MACRO_LITERAL(74), %al   // if (al == 'J') goto FOUND_LONG
    je 2f
    cmpb MACRO_LITERAL(70), %al   // if (al == 'F') goto SKIP_FLOAT
    je 3f
    cmpb MACRO_LITERAL(68), %al   // if (al == 'D') goto SKIP_DOUBLE
    je 4f
    movl (%r11), REG_VAR(gpr_reg32, 1)
    addq MACRO_LITERAL(4), %r11   // arg_array++
    jmp 5f
2:  // FOUND_LONG
    movq (%r11), REG_VAR(gpr_reg64, 0)
    addq MACRO_LITERAL(8), %r11   // arg_array+=2
    jmp 5f
3:  // SKIP_FLOAT
    addq MACRO_LITERAL(4), %r11   // arg_array++
    jmp 1b
4:  // SKIP_DOUBLE
    addq MACRO_LITERAL(8), %r11   // arg_array+=2
    jmp 1b
5:
END_MACRO

    /*
     * Quick invocation stub.
     * On entry:
     *   [sp] = return address
     *   rdi = method pointer
     *   rsi = argument array that must at least contain the this pointer.
     *   rdx = size of argument array in bytes
     *   rcx = (managed) thread pointer
     *   r8 = JValue* result
     *   r9 = char* shorty
     */
DEFINE_FUNCTION art_quick_invoke_stub
    // Set up argument XMM registers.
    leaq 1(%r9), %r10             // R10 := shorty + 1  ; ie skip return arg character.
    leaq 4(%rsi), %r11            // R11 := arg_array + 4 ; ie skip this pointer.
    LOOP_OVER_SHORTY_LOADING_XMMS xmm0, .Lxmm_setup_finished
    LOOP_OVER_SHORTY_LOADING_XMMS xmm1, .Lxmm_setup_finished
    LOOP_OVER_SHORTY_LOADING_XMMS xmm2, .Lxmm_setup_finished
    LOOP_OVER_SHORTY_LOADING_XMMS xmm3, .Lxmm_setup_finished
    LOOP_OVER_SHORTY_LOADING_XMMS xmm4, .Lxmm_setup_finished
    LOOP_OVER_SHORTY_LOADING_XMMS xmm5, .Lxmm_setup_finished
    LOOP_OVER_SHORTY_LOADING_XMMS xmm6, .Lxmm_setup_finished
    LOOP_OVER_SHORTY_LOADING_XMMS xmm7, .Lxmm_setup_finished
    .balign 16
.Lxmm_setup_finished:
    PUSH rbp                      // Save rbp.
    PUSH r8                       // Save r8/result*.
    PUSH r9                       // Save r9/shorty*.
    movq %rsp, %rbp               // Copy value of stack pointer into base pointer.
    CFI_DEF_CFA_REGISTER(rbp)

    movl %edx, %r10d
    addl LITERAL(60), %edx        // Reserve space for return addr, StackReference<method>, rbp,
                                  // r8 and r9 in frame.
    andl LITERAL(0xFFFFFFF0), %edx    // Align frame size to 16 bytes.
    subl LITERAL(32), %edx        // Remove space for return address, rbp, r8 and r9.
    subq %rdx, %rsp               // Reserve stack space for argument array.

#if (STACK_REFERENCE_SIZE != 4)
#error "STACK_REFERENCE_SIZE(X86_64) size not as expected."
#endif
    movl LITERAL(0), (%rsp)       // Store NULL for method*

    movl %r10d, %ecx              // Place size of args in rcx.
    movq %rdi, %rax               // RAX := method to be called
    movq %rsi, %r11               // R11 := arg_array
    leaq 4(%rsp), %rdi            // Rdi is pointing just above the StackReference<method> in the
                                  // stack arguments.
    // Copy arg array into stack.
    rep movsb                     // while (rcx--) { *rdi++ = *rsi++ }
    leaq 1(%r9), %r10             // R10 := shorty + 1  ; ie skip return arg character
    movq %rax, %rdi               // RDI := method to be called
    movl (%r11), %esi             // RSI := this pointer
    addq LITERAL(4), %r11         // arg_array++
    LOOP_OVER_SHORTY_LOADING_GPRS rdx, edx, .Lgpr_setup_finished
    LOOP_OVER_SHORTY_LOADING_GPRS rcx, ecx, .Lgpr_setup_finished
    LOOP_OVER_SHORTY_LOADING_GPRS r8, r8d, .Lgpr_setup_finished
    LOOP_OVER_SHORTY_LOADING_GPRS r9, r9d, .Lgpr_setup_finished
.Lgpr_setup_finished:
    call *METHOD_QUICK_CODE_OFFSET(%rdi) // Call the method.
    movq %rbp, %rsp               // Restore stack pointer.
    CFI_DEF_CFA_REGISTER(rsp)
    POP r9                        // Pop r9 - shorty*.
    POP r8                        // Pop r8 - result*.
    POP rbp                       // Pop rbp
    cmpb LITERAL(68), (%r9)       // Test if result type char == 'D'.
    je .Lreturn_double_quick
    cmpb LITERAL(70), (%r9)       // Test if result type char == 'F'.
    je .Lreturn_float_quick
    movq %rax, (%r8)              // Store the result assuming its a long, int or Object*
    ret
.Lreturn_double_quick:
    movsd %xmm0, (%r8)           // Store the double floating point result.
    ret
.Lreturn_float_quick:
    movss %xmm0, (%r8)           // Store the floating point result.
    ret
END_FUNCTION art_quick_invoke_stub

    /*
     * Quick invocation stub.
     * On entry:
     *   [sp] = return address
     *   rdi = method pointer
     *   rsi = argument array or NULL if no arguments.
     *   rdx = size of argument array in bytes
     *   rcx = (managed) thread pointer
     *   r8 = JValue* result
     *   r9 = char* shorty
     */
DEFINE_FUNCTION art_quick_invoke_static_stub
    // Set up argument XMM registers.
    leaq 1(%r9), %r10             // R10 := shorty + 1  ; ie skip return arg character
    movq %rsi, %r11               // R11 := arg_array
    LOOP_OVER_SHORTY_LOADING_XMMS xmm0, .Lxmm_setup_finished2
    LOOP_OVER_SHORTY_LOADING_XMMS xmm1, .Lxmm_setup_finished2
    LOOP_OVER_SHORTY_LOADING_XMMS xmm2, .Lxmm_setup_finished2
    LOOP_OVER_SHORTY_LOADING_XMMS xmm3, .Lxmm_setup_finished2
    LOOP_OVER_SHORTY_LOADING_XMMS xmm4, .Lxmm_setup_finished2
    LOOP_OVER_SHORTY_LOADING_XMMS xmm5, .Lxmm_setup_finished2
    LOOP_OVER_SHORTY_LOADING_XMMS xmm6, .Lxmm_setup_finished2
    LOOP_OVER_SHORTY_LOADING_XMMS xmm7, .Lxmm_setup_finished2
    .balign 16
.Lxmm_setup_finished2:
    PUSH rbp                      // Save rbp.
    PUSH r8                       // Save r8/result*.
    PUSH r9                       // Save r9/shorty*.
    movq %rsp, %rbp               // Copy value of stack pointer into base pointer.
    CFI_DEF_CFA_REGISTER(rbp)

    movl %edx, %r10d
    addl LITERAL(60), %edx        // Reserve space for return addr, StackReference<method>, rbp,
                                  // r8 and r9 in frame.
    andl LITERAL(0xFFFFFFF0), %edx    // Align frame size to 16 bytes.
    subl LITERAL(32), %edx        // Remove space for return address, rbp, r8 and r9.
    subq %rdx, %rsp               // Reserve stack space for argument array.

#if (STACK_REFERENCE_SIZE != 4)
#error "STACK_REFERENCE_SIZE(X86_64) size not as expected."
#endif
    movl LITERAL(0), (%rsp)       // Store NULL for method*

    movl %r10d, %ecx              // Place size of args in rcx.
    movq %rdi, %rax               // RAX := method to be called
    movq %rsi, %r11               // R11 := arg_array
    leaq 4(%rsp), %rdi            // Rdi is pointing just above the StackReference<method> in the
                                  // stack arguments.
    // Copy arg array into stack.
    rep movsb                     // while (rcx--) { *rdi++ = *rsi++ }
    leaq 1(%r9), %r10             // R10 := shorty + 1  ; ie skip return arg character
    movq %rax, %rdi               // RDI := method to be called
    LOOP_OVER_SHORTY_LOADING_GPRS rsi, esi, .Lgpr_setup_finished2
    LOOP_OVER_SHORTY_LOADING_GPRS rdx, edx, .Lgpr_setup_finished2
    LOOP_OVER_SHORTY_LOADING_GPRS rcx, ecx, .Lgpr_setup_finished2
    LOOP_OVER_SHORTY_LOADING_GPRS r8, r8d, .Lgpr_setup_finished2
    LOOP_OVER_SHORTY_LOADING_GPRS r9, r9d, .Lgpr_setup_finished2
.Lgpr_setup_finished2:
    call *METHOD_QUICK_CODE_OFFSET(%rdi) // Call the method.
    movq %rbp, %rsp               // Restore stack pointer.
    CFI_DEF_CFA_REGISTER(rsp)
    POP r9                        // Pop r9 - shorty*.
    POP r8                        // Pop r8 - result*.
    POP rbp                       // Pop rbp
    cmpb LITERAL(68), (%r9)       // Test if result type char == 'D'.
    je .Lreturn_double_quick2
    cmpb LITERAL(70), (%r9)       // Test if result type char == 'F'.
    je .Lreturn_float_quick2
    movq %rax, (%r8)              // Store the result assuming its a long, int or Object*
    ret
.Lreturn_double_quick2:
    movsd %xmm0, (%r8)           // Store the double floating point result.
    ret
.Lreturn_float_quick2:
    movss %xmm0, (%r8)           // Store the floating point result.
    ret
END_FUNCTION art_quick_invoke_static_stub

MACRO3(NO_ARG_DOWNCALL, c_name, cxx_name, return_macro)
    DEFINE_FUNCTION VAR(c_name, 0)
    SETUP_REF_ONLY_CALLEE_SAVE_FRAME  // save ref containing registers for GC
    // Outgoing argument set up
    movq %rsp, %rsi                   // pass SP
    movq %gs:THREAD_SELF_OFFSET, %rdi // pass Thread::Current()
    call PLT_VAR(cxx_name, 1)         // cxx_name(Thread*, SP)
    RESTORE_REF_ONLY_CALLEE_SAVE_FRAME  // restore frame up to return address
    CALL_MACRO(return_macro, 2)       // return or deliver exception
    END_FUNCTION VAR(c_name, 0)
END_MACRO

MACRO3(ONE_ARG_DOWNCALL, c_name, cxx_name, return_macro)
    DEFINE_FUNCTION VAR(c_name, 0)
    SETUP_REF_ONLY_CALLEE_SAVE_FRAME   // save ref containing registers for GC
    // Outgoing argument set up
    movq %rsp, %rdx                    // pass SP
    movq %gs:THREAD_SELF_OFFSET, %rsi  // pass Thread::Current()
    call PLT_VAR(cxx_name, 1)          // cxx_name(arg0, Thread*, SP)
    RESTORE_REF_ONLY_CALLEE_SAVE_FRAME  // restore frame up to return address
    CALL_MACRO(return_macro, 2)        // return or deliver exception
    END_FUNCTION VAR(c_name, 0)
END_MACRO

MACRO3(TWO_ARG_DOWNCALL, c_name, cxx_name, return_macro)
    DEFINE_FUNCTION VAR(c_name, 0)
    SETUP_REF_ONLY_CALLEE_SAVE_FRAME   // save ref containing registers for GC
    // Outgoing argument set up
    movq %rsp, %rcx                    // pass SP
    movq %gs:THREAD_SELF_OFFSET, %rdx  // pass Thread::Current()
    call PLT_VAR(cxx_name, 1)          // cxx_name(arg0, arg1, Thread*, SP)
    RESTORE_REF_ONLY_CALLEE_SAVE_FRAME  // restore frame up to return address
    CALL_MACRO(return_macro, 2)       // return or deliver exception
    END_FUNCTION VAR(c_name, 0)
END_MACRO

MACRO3(THREE_ARG_DOWNCALL, c_name, cxx_name, return_macro)
    DEFINE_FUNCTION VAR(c_name, 0)
    SETUP_REF_ONLY_CALLEE_SAVE_FRAME   // save ref containing registers for GC
    // Outgoing argument set up
    movq %rsp, %r8                     // pass SP
    movq %gs:THREAD_SELF_OFFSET, %rcx  // pass Thread::Current()
    call PLT_VAR(cxx_name, 1)          // cxx_name(arg0, arg1, arg2, Thread*, SP)
    RESTORE_REF_ONLY_CALLEE_SAVE_FRAME // restore frame up to return address
    CALL_MACRO(return_macro, 2)        // return or deliver exception
    END_FUNCTION VAR(c_name, 0)
END_MACRO

MACRO0(RETURN_IF_RESULT_IS_NON_ZERO)
    testq %rax, %rax               // rax == 0 ?
    jz  1f                         // if rax == 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

MACRO0(RETURN_OR_DELIVER_PENDING_EXCEPTION)
    movq %gs:THREAD_EXCEPTION_OFFSET, %rcx // get exception field
    testq %rcx, %rcx               // rcx == 0 ?
    jnz 1f                         // if rcx != 0 goto 1
    ret                            // return
1:                                 // deliver exception on current thread
    DELIVER_PENDING_EXCEPTION
END_MACRO

// Generate the allocation entrypoints for each allocator.
// TODO: use arch/quick_alloc_entrypoints.S. Currently we don't as we need to use concatenation
// macros to work around differences between OS/X's as and binutils as (OS/X lacks named arguments
// to macros and the VAR macro won't concatenate arguments properly), this also breaks having
// multi-line macros that use each other (hence using 1 macro per newline below).
#define GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT(c_suffix, cxx_suffix) \
  TWO_ARG_DOWNCALL art_quick_alloc_object ## c_suffix, artAllocObjectFromCode ## cxx_suffix, RETURN_IF_RESULT_IS_NON_ZERO
#define GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_RESOLVED(c_suffix, cxx_suffix) \
  TWO_ARG_DOWNCALL art_quick_alloc_object_resolved ## c_suffix, artAllocObjectFromCodeResolved ## cxx_suffix, RETURN_IF_RESULT_IS_NON_ZERO
#define GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_INITIALIZED(c_suffix, cxx_suffix) \
  TWO_ARG_DOWNCALL art_quick_alloc_object_initialized ## c_suffix, artAllocObjectFromCodeInitialized ## cxx_suffix, RETURN_IF_RESULT_IS_NON_ZERO
#define GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_WITH_ACCESS_CHECK(c_suffix, cxx_suffix) \
  TWO_ARG_DOWNCALL art_quick_alloc_object_with_access_check ## c_suffix, artAllocObjectFromCodeWithAccessCheck ## cxx_suffix, RETURN_IF_RESULT_IS_NON_ZERO
#define GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY(c_suffix, cxx_suffix) \
  THREE_ARG_DOWNCALL art_quick_alloc_array ## c_suffix, artAllocArrayFromCode ## cxx_suffix, RETURN_IF_RESULT_IS_NON_ZERO
#define GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY_RESOLVED(c_suffix, cxx_suffix) \
  THREE_ARG_DOWNCALL art_quick_alloc_array_resolved ## c_suffix, artAllocArrayFromCodeResolved ## cxx_suffix, RETURN_IF_RESULT_IS_NON_ZERO
#define GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY_WITH_ACCESS_CHECK(c_suffix, cxx_suffix) \
  THREE_ARG_DOWNCALL art_quick_alloc_array_with_access_check ## c_suffix, artAllocArrayFromCodeWithAccessCheck ## cxx_suffix, RETURN_IF_RESULT_IS_NON_ZERO
#define GENERATE_ALLOC_ENTRYPOINTS_CHECK_AND_ALLOC_ARRAY(c_suffix, cxx_suffix) \
  THREE_ARG_DOWNCALL art_quick_check_and_alloc_array ## c_suffix, artCheckAndAllocArrayFromCode ## cxx_suffix, RETURN_IF_RESULT_IS_NON_ZERO
#define GENERATE_ALLOC_ENTRYPOINTS_CHECK_AND_ALLOC_ARRAY_WITH_ACCESS_CHECK(c_suffix, cxx_suffix) \
  THREE_ARG_DOWNCALL art_quick_check_and_alloc_array_with_access_check ## c_suffix, artCheckAndAllocArrayFromCodeWithAccessCheck ## cxx_suffix, RETURN_IF_RESULT_IS_NON_ZERO

GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT(_dlmalloc, DlMalloc)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_RESOLVED(_dlmalloc, DlMalloc)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_INITIALIZED(_dlmalloc, DlMalloc)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_WITH_ACCESS_CHECK(_dlmalloc, DlMalloc)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY(_dlmalloc, DlMalloc)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY_RESOLVED(_dlmalloc, DlMalloc)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY_WITH_ACCESS_CHECK(_dlmalloc, DlMalloc)
GENERATE_ALLOC_ENTRYPOINTS_CHECK_AND_ALLOC_ARRAY(_dlmalloc, DlMalloc)
GENERATE_ALLOC_ENTRYPOINTS_CHECK_AND_ALLOC_ARRAY_WITH_ACCESS_CHECK(_dlmalloc, DlMalloc)

GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT(_dlmalloc_instrumented, DlMallocInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_RESOLVED(_dlmalloc_instrumented, DlMallocInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_INITIALIZED(_dlmalloc_instrumented, DlMallocInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_WITH_ACCESS_CHECK(_dlmalloc_instrumented, DlMallocInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY(_dlmalloc_instrumented, DlMallocInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY_RESOLVED(_dlmalloc_instrumented, DlMallocInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY_WITH_ACCESS_CHECK(_dlmalloc_instrumented, DlMallocInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_CHECK_AND_ALLOC_ARRAY(_dlmalloc_instrumented, DlMallocInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_CHECK_AND_ALLOC_ARRAY_WITH_ACCESS_CHECK(_dlmalloc_instrumented, DlMallocInstrumented)

GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT(_rosalloc, RosAlloc)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_RESOLVED(_rosalloc, RosAlloc)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_INITIALIZED(_rosalloc, RosAlloc)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_WITH_ACCESS_CHECK(_rosalloc, RosAlloc)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY(_rosalloc, RosAlloc)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY_RESOLVED(_rosalloc, RosAlloc)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY_WITH_ACCESS_CHECK(_rosalloc, RosAlloc)
GENERATE_ALLOC_ENTRYPOINTS_CHECK_AND_ALLOC_ARRAY(_rosalloc, RosAlloc)
GENERATE_ALLOC_ENTRYPOINTS_CHECK_AND_ALLOC_ARRAY_WITH_ACCESS_CHECK(_rosalloc, RosAlloc)

GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT(_rosalloc_instrumented, RosAllocInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_RESOLVED(_rosalloc_instrumented, RosAllocInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_INITIALIZED(_rosalloc_instrumented, RosAllocInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_WITH_ACCESS_CHECK(_rosalloc_instrumented, RosAllocInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY(_rosalloc_instrumented, RosAllocInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY_RESOLVED(_rosalloc_instrumented, RosAllocInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY_WITH_ACCESS_CHECK(_rosalloc_instrumented, RosAllocInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_CHECK_AND_ALLOC_ARRAY(_rosalloc_instrumented, RosAllocInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_CHECK_AND_ALLOC_ARRAY_WITH_ACCESS_CHECK(_rosalloc_instrumented, RosAllocInstrumented)

GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT(_bump_pointer, BumpPointer)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_RESOLVED(_bump_pointer, BumpPointer)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_INITIALIZED(_bump_pointer, BumpPointer)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_WITH_ACCESS_CHECK(_bump_pointer, BumpPointer)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY(_bump_pointer, BumpPointer)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY_RESOLVED(_bump_pointer, BumpPointer)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY_WITH_ACCESS_CHECK(_bump_pointer, BumpPointer)
GENERATE_ALLOC_ENTRYPOINTS_CHECK_AND_ALLOC_ARRAY(_bump_pointer, BumpPointer)
GENERATE_ALLOC_ENTRYPOINTS_CHECK_AND_ALLOC_ARRAY_WITH_ACCESS_CHECK(_bump_pointer, BumpPointer)

GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT(_bump_pointer_instrumented, BumpPointerInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_RESOLVED(_bump_pointer_instrumented, BumpPointerInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_INITIALIZED(_bump_pointer_instrumented, BumpPointerInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_WITH_ACCESS_CHECK(_bump_pointer_instrumented, BumpPointerInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY(_bump_pointer_instrumented, BumpPointerInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY_RESOLVED(_bump_pointer_instrumented, BumpPointerInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY_WITH_ACCESS_CHECK(_bump_pointer_instrumented, BumpPointerInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_CHECK_AND_ALLOC_ARRAY(_bump_pointer_instrumented, BumpPointerInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_CHECK_AND_ALLOC_ARRAY_WITH_ACCESS_CHECK(_bump_pointer_instrumented, BumpPointerInstrumented)

GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT(_tlab, TLAB)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_RESOLVED(_tlab, TLAB)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_INITIALIZED(_tlab, TLAB)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_WITH_ACCESS_CHECK(_tlab, TLAB)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY(_tlab, TLAB)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY_RESOLVED(_tlab, TLAB)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY_WITH_ACCESS_CHECK(_tlab, TLAB)
GENERATE_ALLOC_ENTRYPOINTS_CHECK_AND_ALLOC_ARRAY(_tlab, TLAB)
GENERATE_ALLOC_ENTRYPOINTS_CHECK_AND_ALLOC_ARRAY_WITH_ACCESS_CHECK(_tlab, TLAB)

GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT(_tlab_instrumented, TLABInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_RESOLVED(_tlab_instrumented, TLABInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_INITIALIZED(_tlab_instrumented, TLABInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_OBJECT_WITH_ACCESS_CHECK(_tlab_instrumented, TLABInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY(_tlab_instrumented, TLABInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY_RESOLVED(_tlab_instrumented, TLABInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_ALLOC_ARRAY_WITH_ACCESS_CHECK(_tlab_instrumented, TLABInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_CHECK_AND_ALLOC_ARRAY(_tlab_instrumented, TLABInstrumented)
GENERATE_ALLOC_ENTRYPOINTS_CHECK_AND_ALLOC_ARRAY_WITH_ACCESS_CHECK(_tlab_instrumented, TLABInstrumented)

TWO_ARG_DOWNCALL art_quick_resolve_string, artResolveStringFromCode, RETURN_IF_RESULT_IS_NON_ZERO
TWO_ARG_DOWNCALL art_quick_initialize_static_storage, artInitializeStaticStorageFromCode, RETURN_IF_RESULT_IS_NON_ZERO
TWO_ARG_DOWNCALL art_quick_initialize_type, artInitializeTypeFromCode, RETURN_IF_RESULT_IS_NON_ZERO
TWO_ARG_DOWNCALL art_quick_initialize_type_and_verify_access, artInitializeTypeAndVerifyAccessFromCode, RETURN_IF_RESULT_IS_NON_ZERO

TWO_ARG_DOWNCALL art_quick_handle_fill_data, artHandleFillArrayDataFromCode, RETURN_IF_EAX_ZERO

DEFINE_FUNCTION art_quick_lock_object
    testl %edi, %edi                      // Null check object/rdi.
    jz   .Lslow_lock
.Lretry_lock:
    movl LOCK_WORD_OFFSET(%edi), %ecx     // ecx := lock word.
    test LITERAL(0xC0000000), %ecx        // Test the 2 high bits.
    jne  .Lslow_lock                      // Slow path if either of the two high bits are set.
    movl %gs:THREAD_ID_OFFSET, %edx       // edx := thread id
    test %ecx, %ecx
    jnz  .Lalready_thin                   // Lock word contains a thin lock.
    // unlocked case - %edx holds thread id with count of 0
    xor  %eax, %eax                       // eax == 0 for comparison with lock word in cmpxchg
    lock cmpxchg  %edx, LOCK_WORD_OFFSET(%edi)
    jnz  .Lretry_lock                     // cmpxchg failed retry
    ret
.Lalready_thin:
    cmpw %cx, %dx                         // do we hold the lock already?
    jne  .Lslow_lock
    addl LITERAL(65536), %ecx             // increment recursion count
    test LITERAL(0xC0000000), %ecx        // overflowed if either of top two bits are set
    jne  .Lslow_lock                      // count overflowed so go slow
    movl %ecx, LOCK_WORD_OFFSET(%edi)     // update lockword, cmpxchg not necessary as we hold lock
    ret
.Lslow_lock:
    SETUP_REF_ONLY_CALLEE_SAVE_FRAME
    movq %gs:THREAD_SELF_OFFSET, %rsi     // pass Thread::Current()
    movq %rsp, %rdx                       // pass SP
    call PLT_SYMBOL(artLockObjectFromCode)  // artLockObjectFromCode(object, Thread*, SP)
    RESTORE_REF_ONLY_CALLEE_SAVE_FRAME    // restore frame up to return address
    RETURN_IF_EAX_ZERO
END_FUNCTION art_quick_lock_object

DEFINE_FUNCTION art_quick_unlock_object
    testl %edi, %edi                      // null check object/edi
    jz   .Lslow_unlock
    movl LOCK_WORD_OFFSET(%edi), %ecx     // ecx := lock word
    movl %gs:THREAD_ID_OFFSET, %edx       // edx := thread id
    test LITERAL(0xC0000000), %ecx
    jnz  .Lslow_unlock                    // lock word contains a monitor
    cmpw %cx, %dx                         // does the thread id match?
    jne  .Lslow_unlock
    cmpl LITERAL(65536), %ecx
    jae  .Lrecursive_thin_unlock
    movl LITERAL(0), LOCK_WORD_OFFSET(%edi)
    ret
.Lrecursive_thin_unlock:
    subl LITERAL(65536), %ecx
    mov  %ecx, LOCK_WORD_OFFSET(%edi)
    ret
.Lslow_unlock:
    SETUP_REF_ONLY_CALLEE_SAVE_FRAME
    movq %gs:THREAD_SELF_OFFSET, %rsi     // pass Thread::Current()
    movq %rsp, %rdx                       // pass SP
    call PLT_SYMBOL(artUnlockObjectFromCode)  // artUnlockObjectFromCode(object, Thread*, SP)
    RESTORE_REF_ONLY_CALLEE_SAVE_FRAME    // restore frame up to return address
    RETURN_IF_EAX_ZERO
END_FUNCTION art_quick_unlock_object

DEFINE_FUNCTION art_quick_check_cast
    PUSH rdi                          // Save args for exc
    PUSH rsi
    call PLT_SYMBOL(artIsAssignableFromCode)  // (Class* klass, Class* ref_klass)
    testq %rax, %rax
    jz 1f                             // jump forward if not assignable
    addq LITERAL(16), %rsp            // pop arguments
    CFI_ADJUST_CFA_OFFSET(-16)
    ret
1:
    POP rsi                           // Pop arguments
    POP rdi
    SETUP_SAVE_ALL_CALLEE_SAVE_FRAME  // save all registers as basis for long jump context
    mov %rsp, %rcx                    // pass SP
    mov %gs:THREAD_SELF_OFFSET, %rdx  // pass Thread::Current()
    call PLT_SYMBOL(artThrowClassCastException) // (Class* a, Class* b, Thread*, SP)
    int3                              // unreached
END_FUNCTION art_quick_check_cast


    /*
     * Entry from managed code for array put operations of objects where the value being stored
     * needs to be checked for compatibility.
     *
     * Currently all the parameters should fit into the 32b portions of the registers. Index always
     * will. So we optimize for a tighter encoding. The 64b versions are in comments.
     *
     * rdi(edi) = array, rsi(esi) = index, rdx(edx) = value
     */
DEFINE_FUNCTION art_quick_aput_obj_with_null_and_bound_check
    testl %edi, %edi
//  testq %rdi, %rdi
    jnz art_quick_aput_obj_with_bound_check_local
    jmp art_quick_throw_null_pointer_exception_local
END_FUNCTION art_quick_aput_obj_with_null_and_bound_check


DEFINE_FUNCTION art_quick_aput_obj_with_bound_check
    movl ARRAY_LENGTH_OFFSET(%edi), %ecx
//  movl ARRAY_LENGTH_OFFSET(%rdi), %ecx      // This zero-extends, so value(%rcx)=value(%ecx)
    cmpl %ecx, %esi
    jb art_quick_aput_obj_local
    mov %esi, %edi
//  mov %rsi, %rdi
    mov %ecx, %esi
//  mov %rcx, %rsi
    jmp art_quick_throw_array_bounds_local
END_FUNCTION art_quick_aput_obj_with_bound_check


DEFINE_FUNCTION art_quick_aput_obj
    testl %edx, %edx                // store of null
//  test %rdx, %rdx
    jz .Ldo_aput_null
    movl CLASS_OFFSET(%edi), %ecx
//  movq CLASS_OFFSET(%rdi), %rcx
    movl CLASS_COMPONENT_TYPE_OFFSET(%ecx), %ecx
//  movq CLASS_COMPONENT_TYPE_OFFSET(%rcx), %rcx
    cmpl CLASS_OFFSET(%edx), %ecx // value's type == array's component type - trivial assignability
//  cmpq CLASS_OFFSET(%rdx), %rcx
    jne .Lcheck_assignability
.Ldo_aput:
    movl %edx, OBJECT_ARRAY_DATA_OFFSET(%edi, %esi, 4)
//  movq %rdx, OBJECT_ARRAY_DATA_OFFSET(%rdi, %rsi, 4)
    movq %gs:THREAD_CARD_TABLE_OFFSET, %rdx
    shrl LITERAL(7), %edi
//  shrl LITERAL(7), %rdi
    movb %dl, (%rdx, %rdi)                       // Note: this assumes that top 32b of %rdi are zero
    ret
.Ldo_aput_null:
    movl %edx, OBJECT_ARRAY_DATA_OFFSET(%edi, %esi, 4)
//  movq %rdx, OBJECT_ARRAY_DATA_OFFSET(%rdi, %rsi, 4)
    ret
.Lcheck_assignability:
    // Save arguments.
    PUSH rdi
    PUSH rsi
    PUSH rdx
    subq LITERAL(8), %rsp        // Alignment padding.
    CFI_ADJUST_CFA_OFFSET(8)

                                  // "Uncompress" = do nothing, as already zero-extended on load.
    movl CLASS_OFFSET(%edx), %esi // Pass arg2 = value's class.
    movq %rcx, %rdi               // Pass arg1 = array's component type.

    call PLT_SYMBOL(artIsAssignableFromCode)  // (Class* a, Class* b)

    // Exception?
    testq %rax, %rax
    jz   .Lthrow_array_store_exception

    // Restore arguments.
    addq LITERAL(8), %rsp
    CFI_ADJUST_CFA_OFFSET(-8)
    POP  rdx
    POP  rsi
    POP  rdi

    movl %edx, OBJECT_ARRAY_DATA_OFFSET(%edi, %esi, 4)
//  movq %rdx, OBJECT_ARRAY_DATA_OFFSET(%rdi, %rsi, 4)
    movq %gs:THREAD_CARD_TABLE_OFFSET, %rdx
    shrl LITERAL(7), %edi
//  shrl LITERAL(7), %rdi
    movb %dl, (%rdx, %rdi)                       // Note: this assumes that top 32b of %rdi are zero
//  movb %dl, (%rdx, %rdi)
    ret
.Lthrow_array_store_exception:
    // Restore arguments.
    addq LITERAL(8), %rsp
    CFI_ADJUST_CFA_OFFSET(-8)
    POP  rdx
    POP  rsi
    POP  rdi

    SETUP_SAVE_ALL_CALLEE_SAVE_FRAME  // Save all registers as basis for long jump context.

    // Outgoing argument set up.
    movq %rsp, %rcx                         // Pass arg 4 = SP.
    movq %rdx, %rsi                         // Pass arg 2 = value.
    movq %gs:THREAD_SELF_OFFSET, %rdx // Pass arg 3 = Thread::Current().
                                            // Pass arg 1 = array.

    call PLT_SYMBOL(artThrowArrayStoreException) // (array, value, Thread*, SP)
    int3                          // unreached
END_FUNCTION art_quick_aput_obj

// TODO: This is quite silly on X86_64 now.
DEFINE_FUNCTION art_quick_memcpy
    call PLT_SYMBOL(memcpy)       // (void*, const void*, size_t)
    ret
END_FUNCTION art_quick_memcpy

NO_ARG_DOWNCALL art_quick_test_suspend, artTestSuspendFromCode, ret

UNIMPLEMENTED art_quick_ldiv
UNIMPLEMENTED art_quick_lmod
UNIMPLEMENTED art_quick_lmul
UNIMPLEMENTED art_quick_lshl
UNIMPLEMENTED art_quick_lshr
UNIMPLEMENTED art_quick_lushr


MACRO3(ONE_ARG_REF_DOWNCALL, c_name, cxx_name, return_macro)
    DEFINE_FUNCTION VAR(c_name, 0)
    movq 8(%rsp), %rsi                 // pass referrer
    SETUP_REF_ONLY_CALLEE_SAVE_FRAME
                                       // arg0 is in rdi
    movq %gs:THREAD_SELF_OFFSET, %rdx  // pass Thread::Current()
    movq %rsp, %rcx                    // pass SP
    call PLT_VAR(cxx_name, 1)          // cxx_name(arg0, referrer, Thread*, SP)
    RESTORE_REF_ONLY_CALLEE_SAVE_FRAME // restore frame up to return address
    CALL_MACRO(return_macro, 2)
    END_FUNCTION VAR(c_name, 0)
END_MACRO

MACRO3(TWO_ARG_REF_DOWNCALL, c_name, cxx_name, return_macro)
    DEFINE_FUNCTION VAR(c_name, 0)
    movq 8(%rsp), %rdx                 // pass referrer
    SETUP_REF_ONLY_CALLEE_SAVE_FRAME
                                       // arg0 and arg1 are in rdi/rsi
    movq %gs:THREAD_SELF_OFFSET, %rcx  // pass Thread::Current()
    movq %rsp, %r8                     // pass SP
    call PLT_VAR(cxx_name, 1)          // (arg0, arg1, referrer, Thread*, SP)
    RESTORE_REF_ONLY_CALLEE_SAVE_FRAME // restore frame up to return address
    CALL_MACRO(return_macro, 2)
    END_FUNCTION VAR(c_name, 0)
END_MACRO

MACRO3(THREE_ARG_REF_DOWNCALL, c_name, cxx_name, return_macro)
    DEFINE_FUNCTION VAR(c_name, 0)
    movq 8(%rsp), %rcx                 // pass referrer
    SETUP_REF_ONLY_CALLEE_SAVE_FRAME
                                       // arg0, arg1, and arg2 are in rdi/rsi/rdx
    movq %gs:THREAD_SELF_OFFSET, %r8    // pass Thread::Current()
    movq %rsp, %r9                     // pass SP
    call PLT_VAR(cxx_name, 1)          // cxx_name(arg0, arg1, arg2, referrer, Thread*, SP)
    RESTORE_REF_ONLY_CALLEE_SAVE_FRAME // restore frame up to return address
    CALL_MACRO(return_macro, 2)        // return or deliver exception
    END_FUNCTION VAR(c_name, 0)
END_MACRO


THREE_ARG_REF_DOWNCALL art_quick_set32_instance, artSet32InstanceFromCode, RETURN_IF_EAX_ZERO
THREE_ARG_DOWNCALL art_quick_set64_instance, artSet64InstanceFromCode, RETURN_IF_EAX_ZERO
THREE_ARG_REF_DOWNCALL art_quick_set_obj_instance, artSetObjInstanceFromCode, RETURN_IF_EAX_ZERO

TWO_ARG_REF_DOWNCALL art_quick_get32_instance, artGet32InstanceFromCode, RETURN_OR_DELIVER_PENDING_EXCEPTION
TWO_ARG_REF_DOWNCALL art_quick_get64_instance, artGet64InstanceFromCode, RETURN_OR_DELIVER_PENDING_EXCEPTION
TWO_ARG_REF_DOWNCALL art_quick_get_obj_instance, artGetObjInstanceFromCode, RETURN_OR_DELIVER_PENDING_EXCEPTION

TWO_ARG_REF_DOWNCALL art_quick_set32_static, artSet32StaticFromCode, RETURN_IF_EAX_ZERO
TWO_ARG_REF_DOWNCALL art_quick_set_obj_static, artSetObjStaticFromCode, RETURN_IF_EAX_ZERO

ONE_ARG_REF_DOWNCALL art_quick_get32_static, artGet32StaticFromCode, RETURN_OR_DELIVER_PENDING_EXCEPTION
ONE_ARG_REF_DOWNCALL art_quick_get64_static, artGet64StaticFromCode, RETURN_OR_DELIVER_PENDING_EXCEPTION
ONE_ARG_REF_DOWNCALL art_quick_get_obj_static, artGetObjStaticFromCode, RETURN_OR_DELIVER_PENDING_EXCEPTION

// This is singled out as the argument order is different.
DEFINE_FUNCTION art_quick_set64_static
    movq %rsi, %rdx                    // pass new_val
    movq 8(%rsp), %rsi                 // pass referrer
    SETUP_REF_ONLY_CALLEE_SAVE_FRAME
                                       // field_idx is in rdi
    movq %gs:THREAD_SELF_OFFSET, %rcx  // pass Thread::Current()
    movq %rsp, %r8                     // pass SP
    call PLT_SYMBOL(artSet64StaticFromCode)  // (field_idx, referrer, new_val, Thread*, SP)
    RESTORE_REF_ONLY_CALLEE_SAVE_FRAME // restore frame up to return address
    RETURN_IF_EAX_ZERO                 // return or deliver exception
END_FUNCTION art_quick_set64_static


DEFINE_FUNCTION art_quick_proxy_invoke_handler
    // Save callee and GPR args, mixed together to agree with core spills bitmap of ref. and args
    // callee save frame.
    PUSH r15  // Callee save.
    PUSH r14  // Callee save.
    PUSH r13  // Callee save.
    PUSH r12  // Callee save.
    PUSH r9   // Quick arg 5.
    PUSH r8   // Quick arg 4.
    PUSH rsi  // Quick arg 1.
    PUSH rbp  // Callee save.
    PUSH rbx  // Callee save.
    PUSH rdx  // Quick arg 2.
    PUSH rcx  // Quick arg 3.
    // Create space for FPR args and create 2 slots, 1 of padding and 1 for the ArtMethod*.
    subq LITERAL(80), %rsp
    CFI_ADJUST_CFA_OFFSET(80)
    // Save FPRs.
    movq %xmm0, 16(%rsp)
    movq %xmm1, 24(%rsp)
    movq %xmm2, 32(%rsp)
    movq %xmm3, 40(%rsp)
    movq %xmm4, 48(%rsp)
    movq %xmm5, 56(%rsp)
    movq %xmm6, 64(%rsp)
    movq %xmm7, 72(%rsp)
    // Store proxy method to bottom of stack.
    movq %rdi, 0(%rsp)
    movq %gs:THREAD_SELF_OFFSET, %rdx  // Pass Thread::Current().
    movq %rsp, %rcx                    // Pass SP.
    call PLT_SYMBOL(artQuickProxyInvokeHandler) // (proxy method, receiver, Thread*, SP)
    movq %rax, %xmm0                   // Copy return value in case of float returns.
    addq LITERAL(168), %rsp            // Pop arguments.
    CFI_ADJUST_CFA_OFFSET(-168)
    RETURN_OR_DELIVER_PENDING_EXCEPTION
END_FUNCTION art_quick_proxy_invoke_handler

    /*
     * Called to resolve an imt conflict. Clobbers %rax (which will be clobbered later anyways).
     *
     * xmm0 is a hidden argument that holds the target method's dex method index.
     * TODO: With proper hard-float support, this needs to be kept in sync with the quick compiler.
     */
DEFINE_FUNCTION art_quick_imt_conflict_trampoline
    movq 16(%rsp), %rdi            // load caller Method*
    movl METHOD_DEX_CACHE_METHODS_OFFSET(%rdi), %edi  // load dex_cache_resolved_methods
    movd %xmm0, %rax               // get target method index stored in xmm0
    movl OBJECT_ARRAY_DATA_OFFSET(%rdi, %rax, 4), %edi  // load the target method
    jmp art_quick_invoke_interface_trampoline_local
END_FUNCTION art_quick_imt_conflict_trampoline

DEFINE_FUNCTION art_quick_resolution_trampoline
    SETUP_REF_AND_ARGS_CALLEE_SAVE_FRAME
    movq %gs:THREAD_SELF_OFFSET, %rdx
    movq %rsp, %rcx
    call PLT_SYMBOL(artQuickResolutionTrampoline) // (called, receiver, Thread*, SP)
    movq %rax, %r10               // Remember returned code pointer in R10.
    movq (%rsp), %rdi             // Load called method into RDI.
    RESTORE_REF_AND_ARGS_CALLEE_SAVE_FRAME
    testq %r10, %r10              // If code pointer is NULL goto deliver pending exception.
    jz 1f
    jmp *%r10                     // Tail call into method.
1:
    DELIVER_PENDING_EXCEPTION
END_FUNCTION art_quick_resolution_trampoline

/* Generic JNI frame layout:
 *
 * #-------------------#
 * |                   |
 * | caller method...  |
 * #-------------------#    <--- SP on entry
 *
 *          |
 *          V
 *
 * #-------------------#
 * | caller method...  |
 * #-------------------#
 * | Return            |
 * | R15               |    callee save
 * | R14               |    callee save
 * | R13               |    callee save
 * | R12               |    callee save
 * | R9                |    arg5
 * | R8                |    arg4
 * | RSI/R6            |    arg1
 * | RBP/R5            |    callee save
 * | RBX/R3            |    callee save
 * | RDX/R2            |    arg2
 * | RCX/R1            |    arg3
 * | XMM7              |    float arg 8
 * | XMM6              |    float arg 7
 * | XMM5              |    float arg 6
 * | XMM4              |    float arg 5
 * | XMM3              |    float arg 4
 * | XMM2              |    float arg 3
 * | XMM1              |    float arg 2
 * | XMM0              |    float arg 1
 * | Padding           |
 * | RDI/Method*       |  <- sp
 * #-------------------#
 * | Scratch Alloca    |    5K scratch space
 * #---------#---------#
 * |         | sp*     |
 * | Tramp.  #---------#
 * | args    | thread  |
 * | Tramp.  #---------#
 * |         | method  |
 * #-------------------#    <--- SP on artQuickGenericJniTrampoline
 *
 *           |
 *           v              artQuickGenericJniTrampoline
 *
 * #-------------------#
 * | caller method...  |
 * #-------------------#
 * | Return            |
 * | Callee-Save Data  |
 * #-------------------#
 * | handle scope      |
 * #-------------------#
 * | Method*           |    <--- (1)
 * #-------------------#
 * | local ref cookie  | // 4B
 * | handle scope size | // 4B   TODO: roll into call stack alignment?
 * #-------------------#
 * | JNI Call Stack    |
 * #-------------------#    <--- SP on native call
 * |                   |
 * | Stack for Regs    |    The trampoline assembly will pop these values
 * |                   |    into registers for native call
 * #-------------------#
 * | Native code ptr   |
 * #-------------------#
 * | Free scratch      |
 * #-------------------#
 * | Ptr to (1)        |    <--- RSP
 * #-------------------#
 */
    /*
     * Called to do a generic JNI down-call
     */
DEFINE_FUNCTION art_quick_generic_jni_trampoline
    // Save callee and GPR args, mixed together to agree with core spills bitmap.
    PUSH r15  // Callee save.
    PUSH r14  // Callee save.
    PUSH r13  // Callee save.
    PUSH r12  // Callee save.
    PUSH r9   // Quick arg 5.
    PUSH r8   // Quick arg 4.
    PUSH rsi  // Quick arg 1.
    PUSH rbp  // Callee save.
    PUSH rbx  // Callee save.
    PUSH rdx  // Quick arg 2.
    PUSH rcx  // Quick arg 3.
    // Create space for FPR args and create 2 slots, 1 of padding and 1 for the ArtMethod*.
    subq LITERAL(80), %rsp
    CFI_ADJUST_CFA_OFFSET(80)
    // Save FPRs.
    movq %xmm0, 16(%rsp)
    movq %xmm1, 24(%rsp)
    movq %xmm2, 32(%rsp)
    movq %xmm3, 40(%rsp)
    movq %xmm4, 48(%rsp)
    movq %xmm5, 56(%rsp)
    movq %xmm6, 64(%rsp)
    movq %xmm7, 72(%rsp)
    // Store native ArtMethod* to bottom of stack.
    movq %rdi, 0(%rsp)
    movq %rsp, %rbp                 // save SP at callee-save frame
    movq %rsp, %rbx
    CFI_DEF_CFA_REGISTER(rbx)
    //
    // reserve a lot of space
    //
    //      4    local state ref
    //      4    padding
    //   4196    4k scratch space, enough for 2x 256 8-byte parameters (TODO: handle scope overhead?)
    //     16    handle scope member fields ?
    // +  112    14x 8-byte stack-2-register space
    // ------
    //   4332
    // 16-byte aligned: 4336
    // Note: 14x8 = 7*16, so the stack stays aligned for the native call...
    //       Also means: the padding is somewhere in the middle
    //
    //
    // New test: use 5K and release
    // 5k = 5120
    subq LITERAL(5120), %rsp
    // prepare for artQuickGenericJniTrampoline call
    // (Thread*,  SP)
    //    rdi    rsi      <= C calling convention
    //  gs:...   rbp      <= where they are
    movq %gs:THREAD_SELF_OFFSET, %rdi
    movq %rbp, %rsi
    call PLT_SYMBOL(artQuickGenericJniTrampoline)  // (Thread*, sp)

    // At the bottom of the alloca we now have the name pointer to the method=bottom of callee-save
    // get the adjusted frame pointer
    popq %rbp

    // Check for error, negative value.
    test %rax, %rax
    js .Lentry_error

    // release part of the alloca, get the code pointer
    addq %rax, %rsp
    popq %rax

    // pop from the register-passing alloca region
    // what's the right layout?
    popq %rdi
    popq %rsi
    popq %rdx
    popq %rcx
    popq %r8
    popq %r9
    // TODO: skip floating point if unused, some flag.
    movq 0(%rsp), %xmm0
    movq 8(%rsp), %xmm1
    movq 16(%rsp), %xmm2
    movq 24(%rsp), %xmm3
    movq 32(%rsp), %xmm4
    movq 40(%rsp), %xmm5
    movq 48(%rsp), %xmm6
    movq 56(%rsp), %xmm7
    addq LITERAL(64), %rsp          // floating-point done
    // native call
    call *%rax                      // Stack should be aligned 16B without the return addr?
    // result sign extension is handled in C code
    // prepare for artQuickGenericJniEndTrampoline call
    // (Thread*,  SP, result, result_f)
    //   rdi      rsi   rdx   rcx       <= C calling convention
    //  gs:...    rbp   rax   xmm0      <= where they are
    movq %gs:THREAD_SELF_OFFSET, %rdi
    movq %rbp, %rsi
    movq %rax, %rdx
    movq %xmm0, %rcx
    call PLT_SYMBOL(artQuickGenericJniEndTrampoline)

    // Tear down the alloca.
    movq %rbx, %rsp
    CFI_DEF_CFA_REGISTER(rsp)

    // Pending exceptions possible.
    // TODO: use cmpq, needs direct encoding because of gas bug
    movq %gs:THREAD_EXCEPTION_OFFSET, %rcx
    test %rcx, %rcx
    jnz .Lexception_in_native

    // Tear down the callee-save frame.
    // Load FPRs.
    // movq %xmm0, 16(%rsp)         // doesn't make sense!!!
    movq 24(%rsp), %xmm1            // neither does this!!!
    movq 32(%rsp), %xmm2
    movq 40(%rsp), %xmm3
    movq 48(%rsp), %xmm4
    movq 56(%rsp), %xmm5
    movq 64(%rsp), %xmm6
    movq 72(%rsp), %xmm7
    // was 80 bytes
    addq LITERAL(80), %rsp
    CFI_ADJUST_CFA_OFFSET(-80)
    // Save callee and GPR args, mixed together to agree with core spills bitmap.
    POP rcx  // Arg.
    POP rdx  // Arg.
    POP rbx  // Callee save.
    POP rbp  // Callee save.
    POP rsi  // Arg.
    POP r8   // Arg.
    POP r9   // Arg.
    POP r12  // Callee save.
    POP r13  // Callee save.
    POP r14  // Callee save.
    POP r15  // Callee save.
    // store into fpr, for when it's a fpr return...
    movq %rax, %xmm0
    ret
.Lentry_error:
    movq %rbx, %rsp
    CFI_DEF_CFA_REGISTER(rsp)
.Lexception_in_native:
    // TODO: the handle scope contains the this pointer which is used by the debugger for exception
    //       delivery.
    movq %xmm0, 16(%rsp)         // doesn't make sense!!!
    movq 24(%rsp), %xmm1            // neither does this!!!
    movq 32(%rsp), %xmm2
    movq 40(%rsp), %xmm3
    movq 48(%rsp), %xmm4
    movq 56(%rsp), %xmm5
    movq 64(%rsp), %xmm6
    movq 72(%rsp), %xmm7
    // was 80 bytes
    addq LITERAL(80), %rsp
    CFI_ADJUST_CFA_OFFSET(-80)
    // Save callee and GPR args, mixed together to agree with core spills bitmap.
    POP rcx  // Arg.
    POP rdx  // Arg.
    POP rbx  // Callee save.
    POP rbp  // Callee save.
    POP rsi  // Arg.
    POP r8   // Arg.
    POP r9   // Arg.
    POP r12  // Callee save.
    POP r13  // Callee save.
    POP r14  // Callee save.
    POP r15  // Callee save.

    DELIVER_PENDING_EXCEPTION
END_FUNCTION art_quick_generic_jni_trampoline

    /*
     * Called to bridge from the quick to interpreter ABI. On entry the arguments match those
     * of a quick call:
     * RDI = method being called / to bridge to.
     * RSI, RDX, RCX, R8, R9 are arguments to that method.
     */
DEFINE_FUNCTION art_quick_to_interpreter_bridge
    SETUP_REF_AND_ARGS_CALLEE_SAVE_FRAME   // Set up frame and save arguments.
    movq %gs:THREAD_SELF_OFFSET, %rsi      // RSI := Thread::Current()
    movq %rsp, %rdx                        // RDX := sp
    call PLT_SYMBOL(artQuickToInterpreterBridge)  // (method, Thread*, SP)
    RESTORE_REF_AND_ARGS_CALLEE_SAVE_FRAME  // TODO: no need to restore arguments in this case.
    movq %rax, %xmm0                   // Place return value also into floating point return value.
    RETURN_OR_DELIVER_PENDING_EXCEPTION    // return or deliver exception
END_FUNCTION art_quick_to_interpreter_bridge

    /*
     * Routine that intercepts method calls and returns.
     */
UNIMPLEMENTED art_quick_instrumentation_entry
UNIMPLEMENTED art_quick_instrumentation_exit

    /*
     * Instrumentation has requested that we deoptimize into the interpreter. The deoptimization
     * will long jump to the upcall with a special exception of -1.
     */
UNIMPLEMENTED art_quick_deoptimize

    /*
     * String's compareTo.
     *
     * On entry:
     *    rdi:   this string object (known non-null)
     *    rsi:   comp string object (known non-null)
     */
DEFINE_FUNCTION art_quick_string_compareto
    movl STRING_COUNT_OFFSET(%edi), %r8d
    movl STRING_COUNT_OFFSET(%esi), %r9d
    movl STRING_VALUE_OFFSET(%edi), %r10d
    movl STRING_VALUE_OFFSET(%esi), %r11d
    movl STRING_OFFSET_OFFSET(%edi), %eax
    movl STRING_OFFSET_OFFSET(%esi), %ecx
    /* Build pointers to the start of string data */
    leal STRING_DATA_OFFSET(%r10d, %eax, 2), %esi
    leal STRING_DATA_OFFSET(%r11d, %ecx, 2), %edi
    /* Calculate min length and count diff */
    movl  %r8d, %ecx
    movl  %r8d, %eax
    subl  %r9d, %eax
    cmovg %r9d, %ecx
    /*
     * At this point we have:
     *   eax: value to return if first part of strings are equal
     *   ecx: minimum among the lengths of the two strings
     *   esi: pointer to this string data
     *   edi: pointer to comp string data
     */
    jecxz .Lkeep_length
    repe cmpsw                    // find nonmatching chars in [%esi] and [%edi], up to length %ecx
    jne .Lnot_equal
.Lkeep_length:
    ret
    .balign 16
.Lnot_equal:
    movzwl  -2(%esi), %eax        // get last compared char from this string
    movzwl  -2(%edi), %ecx        // get last compared char from comp string
    subl  %ecx, %eax              // return the difference
    ret
END_FUNCTION art_quick_string_compareto

UNIMPLEMENTED art_quick_memcmp16