mirror of
https://github.com/logicog/RTLPlayground.git
synced 2026-08-30 14:52:51 +08:00
Tobias Diedrich
c868482669
The presence of the main function is a hardcoded trigger in sdcc that causes the interrupt vectors and atomic rollback helpers to be generated as part of compilation of the file containing the main function. This makes sure the runtime library is correctly initialized and reduces crtstart.asm to contain only the banked call helpers. To ensure that the __interrupt_vect in area HOME is located at the beginning of the firmware, the linker flags are updated to set the HOME start to 0x00000 and the linker object order is modified to have rtlplayground.rel first. Generated code in rtlplayground.asm: ``` ;-------------------------------------------------------- ; interrupt vector ;-------------------------------------------------------- .area HOME (CODE) __interrupt_vect: ljmp __sdcc_gsinit_startup ljmp _isr_ext0 .ds 5 ljmp _isr_timer0 .ds 5 ljmp _isr_ext1 .ds 5 reti .ds 7 ljmp _isr_serial .ds 5 ljmp _isr_timer2 .ds 5 reti .ds 7 reti .ds 7 ljmp _isr_ext2 .ds 5 ljmp _isr_ext3 ; restartable atomic support routines .ds 2 sdcc_atomic_exchange_rollback_start:: nop nop sdcc_atomic_exchange_pdata_impl: movx a, @r0 mov r3, a mov a, r2 movx @r0, a sjmp sdcc_atomic_exchange_exit nop nop sdcc_atomic_exchange_xdata_impl: movx a, @dptr mov r3, a mov a, r2 movx @dptr, a sjmp sdcc_atomic_exchange_exit sdcc_atomic_compare_exchange_idata_impl: mov a, @r0 cjne a, ar2, .+#5 mov a, r3 mov @r0, a ret nop sdcc_atomic_compare_exchange_pdata_impl: movx a, @r0 cjne a, ar2, .+#5 mov a, r3 movx @r0, a ret nop sdcc_atomic_compare_exchange_xdata_impl: movx a, @dptr cjne a, ar2, .+#5 mov a, r3 movx @dptr, a ret sdcc_atomic_exchange_rollback_end:: sdcc_atomic_exchange_gptr_impl:: jnb b.6, sdcc_atomic_exchange_xdata_impl mov r0, dpl jb b.5, sdcc_atomic_exchange_pdata_impl sdcc_atomic_exchange_idata_impl: mov a, r2 xch a, @r0 mov dpl, a ret sdcc_atomic_exchange_exit: mov dpl, r3 ret sdcc_atomic_compare_exchange_gptr_impl:: jnb b.6, sdcc_atomic_compare_exchange_xdata_impl mov r0, dpl jb b.5, sdcc_atomic_compare_exchange_pdata_impl sjmp sdcc_atomic_compare_exchange_idata_impl ```