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-rw-r--r--py/nlrthumb.c134
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diff --git a/py/nlrthumb.c b/py/nlrthumb.c
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+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2013-2016 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"
+#include "py/nlr.h"
+
+#if (!defined(MICROPY_NLR_SETJMP) || !MICROPY_NLR_SETJMP) && (defined(__thumb2__) || defined(__thumb__) || defined(__arm__))
+
+// 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(__ARM_ARCH_6M__)
+ "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
+ "str lr, [r0, #8] \n" // store lr into nlr_buf
+#endif
+
+ "b nlr_push_tail \n" // do the rest in C
+ );
+
+ return 0; // needed to silence compiler warning
+}
+
+unsigned int nlr_push_tail(nlr_buf_t *nlr) {
+ nlr_buf_t **top = &MP_STATE_THREAD(nlr_top);
+ nlr->prev = *top;
+ *top = nlr;
+ return 0; // normal return
+}
+
+void nlr_pop(void) {
+ nlr_buf_t **top = &MP_STATE_THREAD(nlr_top);
+ *top = (*top)->prev;
+}
+
+NORETURN __attribute__((naked)) void nlr_jump(void *val) {
+ nlr_buf_t **top_ptr = &MP_STATE_THREAD(nlr_top);
+ nlr_buf_t *top = *top_ptr;
+ if (top == NULL) {
+ nlr_jump_fail(val);
+ }
+
+ top->ret_val = val;
+ *top_ptr = top->prev;
+
+ __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(__ARM_ARCH_6M__)
+ "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
+ "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
+ );
+
+ for (;;); // needed to silence compiler warning
+}
+
+#endif // (!defined(MICROPY_NLR_SETJMP) || !MICROPY_NLR_SETJMP) && (defined(__thumb2__) || defined(__thumb__) || defined(__arm__))