Before this change _invalid_pc_placeholder pointed to address of _init
function from crti.o
This made GDB input a bit confusing:
0x40080400 in _init ()
(gdb) bt
#0 0x40080400 in _init ()
#1 0x400e519a in test_instr_fetch_prohibited () at /home/alex/git/esp-idf/tools/test_apps/system/panic/main/test_panic.c:271
#2 0x400d89a7 in app_main () at /home/alex/git/esp-idf/tools/test_apps/system/panic/main/test_app_main.c:116
#3 0x400e5f22 in main_task (args=0x0) at /home/alex/git/esp-idf/components/freertos/app_startup.c:208
#4 0x400895a8 in vPortTaskWrapper (pxCode=0x400e5eb0 <main_task>, pvParameters=0x0) at /home/alex/git/esp-idf/components/freertos/FreeRTOS-Kernel/portable/xtensa/port.c:139
After the change GDB prints output that contains a hint:
_invalid_pc_placeholder () at /home/alex/git/esp-idf/components/xtensa/xtensa_vectors.S:2235
2235 UNREACHABLE_INSTRUCTION_CHECK_PREVIOUS_FRAMES
(gdb) bt
#0 _invalid_pc_placeholder () at /home/alex/git/esp-idf/components/xtensa/xtensa_vectors.S:2235
#1 0x400e519e in test_instr_fetch_prohibited () at /home/alex/git/esp-idf/tools/test_apps/system/panic/main/test_panic.c:271
#2 0x400d89ab in app_main () at /home/alex/git/esp-idf/tools/test_apps/system/panic/main/test_app_main.c:116
#3 0x400e5f26 in main_task (args=0x0) at /home/alex/git/esp-idf/components/freertos/app_startup.c:208
#4 0x400895a8 in vPortTaskWrapper (pxCode=0x400e5eb4 <main_task>, pvParameters=0x0) at /home/alex/git/esp-idf/components/freertos/FreeRTOS-Kernel/portable/xtensa/port.c:139
When porting an RTOS to the Xtensa architecture, there are a few files that
are common to all Xtensa RTOS ports. These files form the Xtensa RTOS porting
layer (e.g., "xtensa_vectors.S", "xtensa_context.S"). An Xtensa RTOS port is
expected to provide an RTOS specific "xtensa_rtos.h" header to interface with
the Xtensa RTOS porting layer.
Previously, the Xtensa RTOS porting layer files were placed in the FreeRTOS
component. This commit does the following:
1. Moves the Xtensa RTOS porting layer files from the `freertos` component to
the `xtensa` component. The following files were moved:
- xtensa_asm_utils.h
- xtensa_context.S
- xtensa_loadstore_handler.S
- xtensa_vectors.S
2. Refactored xtensa component include paths to separate Xtensa RTOS porting
layer headers.
- Xtensa HAL headers included via `#include <xtensa/...h>`
- Xtensa RTOS porting layer headers included via `#include <...h>`
Note: The xtensa files in the Amazon SMP FreeRTOS port are not moved/deleted in
this commit to ensure the moved files retain a clean diff history.
