/*
 * ===========================================================================
 *  Common subroutines and data
 * ===========================================================================
 */

    .text
    .align  2

/*
 * We've detected a condition that will result in an exception, but the exception
 * has not yet been thrown.  Just bail out to the reference interpreter to deal with it.
 * TUNING: for consistency, we may want to just go ahead and handle these here.
 */
#define MTERP_LOGGING 0
common_errDivideByZero:
    EXPORT_PC
#if MTERP_LOGGING
    mov  r0, rSELF
    add  r1, rFP, #OFF_FP_SHADOWFRAME
    bl MterpLogDivideByZeroException
#endif
    b MterpCommonFallback

common_errArrayIndex:
    EXPORT_PC
#if MTERP_LOGGING
    mov  r0, rSELF
    add  r1, rFP, #OFF_FP_SHADOWFRAME
    bl MterpLogArrayIndexException
#endif
    b MterpCommonFallback

common_errNegativeArraySize:
    EXPORT_PC
#if MTERP_LOGGING
    mov  r0, rSELF
    add  r1, rFP, #OFF_FP_SHADOWFRAME
    bl MterpLogNegativeArraySizeException
#endif
    b MterpCommonFallback

common_errNoSuchMethod:
    EXPORT_PC
#if MTERP_LOGGING
    mov  r0, rSELF
    add  r1, rFP, #OFF_FP_SHADOWFRAME
    bl MterpLogNoSuchMethodException
#endif
    b MterpCommonFallback

common_errNullObject:
    EXPORT_PC
#if MTERP_LOGGING
    mov  r0, rSELF
    add  r1, rFP, #OFF_FP_SHADOWFRAME
    bl MterpLogNullObjectException
#endif
    b MterpCommonFallback

common_exceptionThrown:
    EXPORT_PC
#if MTERP_LOGGING
    mov  r0, rSELF
    add  r1, rFP, #OFF_FP_SHADOWFRAME
    bl MterpLogExceptionThrownException
#endif
    b MterpCommonFallback

MterpSuspendFallback:
    EXPORT_PC
#if MTERP_LOGGING
    mov  r0, rSELF
    add  r1, rFP, #OFF_FP_SHADOWFRAME
    ldr  r2, [rSELF, #THREAD_FLAGS_OFFSET]
    bl MterpLogSuspendFallback
#endif
    b MterpCommonFallback

/*
 * If we're here, something is out of the ordinary.  If there is a pending
 * exception, handle it.  Otherwise, roll back and retry with the reference
 * interpreter.
 */
MterpPossibleException:
    ldr     r0, [rSELF, #THREAD_EXCEPTION_OFFSET]
    cmp     r0, #0                                  @ Exception pending?
    beq     MterpFallback                           @ If not, fall back to reference interpreter.
    /* intentional fallthrough - handle pending exception. */
/*
 * On return from a runtime helper routine, we've found a pending exception.
 * Can we handle it here - or need to bail out to caller?
 *
 */
MterpException:
    mov     r0, rSELF
    add     r1, rFP, #OFF_FP_SHADOWFRAME
    bl      MterpHandleException                    @ (self, shadow_frame)
    cmp     r0, #0
    beq     MterpExceptionReturn                    @ no local catch, back to caller.
    ldr     r0, [rFP, #OFF_FP_CODE_ITEM]
    ldr     r1, [rFP, #OFF_FP_DEX_PC]
    ldr     rIBASE, [rSELF, #THREAD_CURRENT_IBASE_OFFSET]
    add     rPC, r0, #CODEITEM_INSNS_OFFSET
    add     rPC, rPC, r1, lsl #1                    @ generate new dex_pc_ptr
    str     rPC, [rFP, #OFF_FP_DEX_PC_PTR]
    /* resume execution at catch block */
    FETCH_INST
    GET_INST_OPCODE ip
    GOTO_OPCODE ip
    /* NOTE: no fallthrough */

/*
 * Check for suspend check request.  Assumes rINST already loaded, rPC advanced and
 * still needs to get the opcode and branch to it, and flags are in lr.
 */
MterpCheckSuspendAndContinue:
    ldr     rIBASE, [rSELF, #THREAD_CURRENT_IBASE_OFFSET]  @ refresh rIBASE
    EXPORT_PC
    mov     r0, rSELF
    ands    lr, #(THREAD_SUSPEND_REQUEST | THREAD_CHECKPOINT_REQUEST)
    blne    MterpSuspendCheck           @ (self)
    GET_INST_OPCODE ip                  @ extract opcode from rINST
    GOTO_OPCODE ip                      @ jump to next instruction

/*
 * Bail out to reference interpreter.
 */
MterpFallback:
    EXPORT_PC
#if MTERP_LOGGING
    mov  r0, rSELF
    add  r1, rFP, #OFF_FP_SHADOWFRAME
    bl MterpLogFallback
#endif
MterpCommonFallback:
    mov     r0, #0                                  @ signal retry with reference interpreter.
    b       MterpDone

/*
 * We pushed some registers on the stack in ExecuteMterpImpl, then saved
 * SP and LR.  Here we restore SP, restore the registers, and then restore
 * LR to PC.
 *
 * On entry:
 *  uint32_t* rFP  (should still be live, pointer to base of vregs)
 */
MterpExceptionReturn:
    mov     r0, #1                                  @ signal return to caller.
    b MterpDone
MterpReturn:
    ldr     r2, [rFP, #OFF_FP_RESULT_REGISTER]
    str     r0, [r2]
    str     r1, [r2, #4]
    mov     r0, #1                                  @ signal return to caller.
MterpDone:
    add     sp, sp, #4                              @ un-align 64
    ldmfd   sp!, {r4-r10,fp,pc}                     @ restore 9 regs and return


    .fnend
    .size   ExecuteMterpImpl, .-ExecuteMterpImpl