/*
 * This file is part of the MicroPython project, http://micropython.org/
 *
 * The MIT License (MIT)
 *
 * Copyright (c) 2013-2017 Damien P. George
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include "py/mpstate.h"

#if MICROPY_NLR_THUMB

#undef nlr_push

// We only need the functions here if we are on arm/thumb, and we are not
// using setjmp/longjmp.
//
// For reference, arm/thumb callee save regs are:
// r4-r11, r13=sp

__attribute__((naked)) unsigned int nlr_push(nlr_buf_t *nlr) {

 __asm volatile (
 "str r4, [r0, #12] \n" // store r4 into nlr_buf
 "str r5, [r0, #16] \n" // store r5 into nlr_buf
 "str r6, [r0, #20] \n" // store r6 into nlr_buf
 "str r7, [r0, #24] \n" // store r7 into nlr_buf

 #if !defined(__thumb2__)
 "mov r1, r8 \n"
 "str r1, [r0, #28] \n" // store r8 into nlr_buf
 "mov r1, r9 \n"
 "str r1, [r0, #32] \n" // store r9 into nlr_buf
 "mov r1, r10 \n"
 "str r1, [r0, #36] \n" // store r10 into nlr_buf
 "mov r1, r11 \n"
 "str r1, [r0, #40] \n" // store r11 into nlr_buf
 "mov r1, r13 \n"
 "str r1, [r0, #44] \n" // store r13=sp into nlr_buf
 "mov r1, lr \n"
 "str r1, [r0, #8] \n" // store lr into nlr_buf
 #else
 "str r8, [r0, #28] \n" // store r8 into nlr_buf
 "str r9, [r0, #32] \n" // store r9 into nlr_buf
 "str r10, [r0, #36] \n" // store r10 into nlr_buf
 "str r11, [r0, #40] \n" // store r11 into nlr_buf
 "str r13, [r0, #44] \n" // store r13=sp into nlr_buf
 #if MICROPY_NLR_NUM_REGS == 16
 "vstr d8, [r0, #48] \n" // store s16-s17 into nlr_buf
 "vstr d9, [r0, #56] \n" // store s18-s19 into nlr_buf
 "vstr d10, [r0, #64] \n" // store s20-s21 into nlr_buf
 #endif
 "str lr, [r0, #8] \n" // store lr into nlr_buf
 #endif

 #if !defined(__thumb2__)
 "ldr r1, nlr_push_tail_var \n"
 "bx r1 \n" // do the rest in C
 ".align 2 \n"
 "nlr_push_tail_var: .word nlr_push_tail \n"
 #else
 #if defined(__APPLE__) || defined(__MACH__)
 "b _nlr_push_tail \n" // do the rest in C
 #else
 "b nlr_push_tail \n" // do the rest in C
 #endif
 #endif
 );

 #if !defined(__clang__) && defined(__GNUC__) && (__GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 8))
 // Older versions of gcc give an error when naked functions don't return a value
 // Additionally exclude Clang as it also defines __GNUC__ but doesn't need this statement
 return 0;
 #endif
}

NORETURN void nlr_jump(void *val) {
 MP_NLR_JUMP_HEAD(val, top)

 __asm volatile (
 "mov r0, %0 \n" // r0 points to nlr_buf
 "ldr r4, [r0, #12] \n" // load r4 from nlr_buf
 "ldr r5, [r0, #16] \n" // load r5 from nlr_buf
 "ldr r6, [r0, #20] \n" // load r6 from nlr_buf
 "ldr r7, [r0, #24] \n" // load r7 from nlr_buf

 #if !defined(__thumb2__)
 "ldr r1, [r0, #28] \n" // load r8 from nlr_buf
 "mov r8, r1 \n"
 "ldr r1, [r0, #32] \n" // load r9 from nlr_buf
 "mov r9, r1 \n"
 "ldr r1, [r0, #36] \n" // load r10 from nlr_buf
 "mov r10, r1 \n"
 "ldr r1, [r0, #40] \n" // load r11 from nlr_buf
 "mov r11, r1 \n"
 "ldr r1, [r0, #44] \n" // load r13=sp from nlr_buf
 "mov r13, r1 \n"
 "ldr r1, [r0, #8] \n" // load lr from nlr_buf
 "mov lr, r1 \n"
 #else
 "ldr r8, [r0, #28] \n" // load r8 from nlr_buf
 "ldr r9, [r0, #32] \n" // load r9 from nlr_buf
 "ldr r10, [r0, #36] \n" // load r10 from nlr_buf
 "ldr r11, [r0, #40] \n" // load r11 from nlr_buf
 "ldr r13, [r0, #44] \n" // load r13=sp from nlr_buf
 #if MICROPY_NLR_NUM_REGS == 16
 "vldr d8, [r0, #48] \n" // load s16-s17 from nlr_buf
 "vldr d9, [r0, #56] \n" // load s18-s19 from nlr_buf
 "vldr d10, [r0, #64] \n" // load s20-s21 from nlr_buf
 #endif
 "ldr lr, [r0, #8] \n" // load lr from nlr_buf
 #endif
 "movs r0, #1 \n" // return 1, non-local return
 "bx lr \n" // return
 : // output operands
 : "r" (top) // input operands
 : // clobbered registers
 );

 MP_UNREACHABLE
}

#endif // MICROPY_NLR_THUMB