diff options
Diffstat (limited to 'libgloss/msp430/crt0.S')
| -rw-r--r-- | libgloss/msp430/crt0.S | 165 |
1 files changed, 61 insertions, 104 deletions
diff --git a/libgloss/msp430/crt0.S b/libgloss/msp430/crt0.S index 42464ddbe..88876cd48 100644 --- a/libgloss/msp430/crt0.S +++ b/libgloss/msp430/crt0.S @@ -52,28 +52,25 @@ __msp430_resetvec_hook: START_CRT_FUNC 0000 start .refsym __msp430_resetvec_hook -#ifdef MINRT - .refsym __crt0_call_just_main -#else - .refsym __crt0_call_init_then_main -#endif + .refsym __crt0_call_main mov_ #__stack, R1 END_CRT_FUNC start #endif -;; Some of the CRT functions below will only be present in the final linked -;; executable if the assembler decides they are needed. It will only define -;; the symbol necessary to prevent them being garbage collected by the linker -;; if the file being assembled has a specific section. -;; The CRT functions this applies to are: -;; init_bss, movedata, move_highdata, init_highbss, run_init_array, -;; run_preinit_array, run_fini_array and run_array. +;; The CRT functions below will only be present in the final linked +;; executable if the assembler decides they are needed. The assembler will +;; only define the symbol necessary to prevent them being garbage collected +;; by the linker if the file being assembled has a specific section, +;; or some other criteria is met. +;; The exception to this is __crt0_call_exit. GCC will include this function +;; if it detects that main() has an epilogue. For example, if main() has a +;; while(1) loop at the end, GCC will not generate an epilogue (since it won't +;; return) and __crt0_call_exit won't be included. #if Lbss -;; Note - this section is only included in the startup code of the -;; application if it is needed. It is responsible for initializing -;; the contents of the .bss section. +;; This function is responsible for initializing the contents of the +;; .bss section. START_CRT_FUNC 0100 init_bss @@ -91,9 +88,8 @@ END_CRT_FUNC init_bss #ifdef __MSP430X_LARGE__ #if Lhigh_bss -;; Note - this section is only included in the startup code of the -;; application if it is needed. It is responsible for initializing -;; the contents of the .upper.bss section. +;; This function is responsible for initializing the contents of the +;; .upper.bss section. START_CRT_FUNC 0200 init_highbss @@ -112,8 +108,7 @@ END_CRT_FUNC init_highbss #if Lmovedata -;; Note - this section is only included in the startup code of the -;; application if it is needed. It is responsible for copying the +;; This function is responsible for copying the ;; contents of the .data section from its load address (in ROM) to ;; its run-time address (in RAM). @@ -136,8 +131,7 @@ END_CRT_FUNC movedata #ifdef __MSP430X_LARGE__ #if Lmove_highdata -;; Note - this section is only included in the startup code of the application -;; if it is needed. It is responsible either for making sure that the +;; This function is responsible for making sure that the ;; contents of the .upper.data section have their correct startup values. ;; If a copy of the .upper.data section is stored in ROM then this means ;; copying the contents into HIFRAM. If a copy of .upper.data is stored in a @@ -175,44 +169,62 @@ END_CRT_FUNC move_highdata #endif /* Lmove_highdata */ #endif /* __MSP430X_LARGE__ */ +#if Lrun_preinit_array +;; This function is responsible for setting up the arguments +;; required for __crt0_run_array, to run the functions in .preinit_array. +START_CRT_FUNC 0500 run_preinit_array + + mov_ #__preinit_array_start, R4 + mov_ #__preinit_array_end, R5 + mov_ #PTRsz, R6 + call_ #__crt0_run_array -#if Lmain_minrt -;; Note - this section is only included in the startup code of the -;; application if it is needed. It is responsible for just calling -;; main. No initialization code is called first, and main is not -;; expected to return. +END_CRT_FUNC run_preinit_array +#endif /* Lrun_preinit_array */ -START_CRT_FUNC 0600 call_just_main +#if Lrun_init_array +;; This function is responsible for setting up the arguments +;; required for __crt0_run_array, to run the functions in .init_array. +START_CRT_FUNC 0600 run_init_array - clr.w R12 ; Set argc == 0 - call_ #main -END_CRT_FUNC call_just_main -#endif /* Lmain_minrt */ + mov_ #__init_array_start, R4 + mov_ #__init_array_end, R5 + mov_ #PTRsz, R6 + call_ #__crt0_run_array +END_CRT_FUNC run_init_array +#endif /* Lrun_init_array */ -#if Lmain -;; Note - this section is only included in the startup code of the -;; application if it is needed. It is responsible for calling the -;; initialization code - constructors, etc - and then main. If main -;; returns then the following section should be present to catch it. +;; FIXME: There are currently no program termination routines executed for +;; msp430. +#if 0 +#if Lrun_fini_array +;; Ensure global C++ destructors in .fini_array are called on exit +;; by registering __crt0_run_fini_array with atexit. +START_CRT_FUNC 0700 register_fini_array + + mov_ #__crt0_run_fini_array, R12 + call_ #atexit + +END_CRT_FUNC register_fini_array +#endif /* Lrun_fini_array */ +#endif /* 0 */ -START_CRT_FUNC 0700 call_init_then_main +#if Lmain +;; This function is always included and calls main(). - call_ #__msp430_init +START_CRT_FUNC 0800 call_main clr.w R12 ; Set argc == 0 call_ #main -END_CRT_FUNC call_init_then_main +END_CRT_FUNC call_main #endif /* Lmain */ - #if Lcallexit -;; Note - this section is only included in the startup code of the -;; application if it is needed. It is responsible for calling exit -;; once main has finished. +;; This function is responsible for calling exit once main has finished. -START_CRT_FUNC 0800 call_exit +START_CRT_FUNC 0900 call_exit call_ #_exit @@ -221,46 +233,15 @@ END_CRT_FUNC call_exit ;---------------------------------------- -#ifndef MINRT - -#if Lrun_preinit_array -;; Note - this section is only included in the startup code of the application -;; if it is needed. It is responsible for setting up the arguments -;; required for __crt0_run_array, to run the functions in .preinit_array. -START_CRT_FUNC 0910 run_preinit_array - - mov_ #__preinit_array_start, R4 - mov_ #__preinit_array_end, R5 - mov_ #PTRsz, R6 - br_ #__crt0_run_array - -END_CRT_FUNC run_preinit_array -#endif /* Lrun_preinit_array */ - -#if Lrun_init_array -;; Note - this section is only included in the startup code of the application -;; if it is needed. It is responsible for setting up the arguments -;; required for __crt0_run_array, to run the functions in .init_array. -START_CRT_FUNC 0920 run_init_array - - mov_ #__init_array_start, R4 - mov_ #__init_array_end, R5 - mov_ #PTRsz, R6 - br_ #__crt0_run_array - -END_CRT_FUNC run_init_array -#endif /* Lrun_init_array */ - #if Lrun_fini_array -;; Note - this section is only included in the startup code of the application -;; if it is needed. It is responsible for setting up the arguments +;; This function is responsible for setting up the arguments ;; required for __crt0_run_array, to run the functions in .fini_array. -START_CRT_FUNC 0930 run_fini_array +START_CRT_FUNC 1000 run_fini_array mov_ #__fini_array_start, R4 mov_ #__fini_array_end, R5 mov_ #-PTRsz, R6 - br_ #__crt0_run_array + call_ #__crt0_run_array END_CRT_FUNC run_fini_array #endif /* Lrun_fini_array */ @@ -268,7 +249,7 @@ END_CRT_FUNC run_fini_array #if Lrun_array ;; Note - this section is only included in the startup code of the application ;; if it is needed by one of the above run_*_array functions. -START_CRT_FUNC 0980 run_array +START_CRT_FUNC 1100 run_array cmp_ R4, R5 jeq _msp430_run_done @@ -282,27 +263,3 @@ END_CRT_FUNC run_array _msp430_run_done: ret_ #endif /* Lrun_array */ - -;---------------------------------------- -#if L0 - - .section .init,"ax" - - .global __msp430_init -__msp430_init: - - .section .fini,"ax" - - .global __msp430_fini -__msp430_fini: - call_ #__crt0_run_fini_array - -;; If this function is not defined externally, we don't need it to do -;; anything. - .text - .weak __crt0_run_fini_array -__crt0_run_fini_array: - ret_ - -#endif -#endif /* not MINRT */ |