Merge branch 'gdb/bt_on_invalid_pc' into 'master'

gdb: Modify PC in case of invalid PC

See merge request espressif/esp-idf!8391

components/esp32/ld/esp32.project.ld.in

@@ -142,6 +142,7 @@ SECTIONS
     . = 0x3C0;
     KEEP(*(.DoubleExceptionVector.text));
     . = 0x400;
+    _invalid_pc_placeholder = ABSOLUTE(.);
     *(.*Vector.literal)
 
     *(.UserEnter.literal);

components/esp32s2/ld/esp32s2.project.ld.in

@@ -142,6 +142,7 @@ SECTIONS
     . = 0x3C0;
     KEEP(*(.DoubleExceptionVector.text));
     . = 0x400;
+    _invalid_pc_placeholder = ABSOLUTE(.);
     *(.*Vector.literal)
 
     *(.UserEnter.literal);

components/esp_gdbstub/xtensa/gdbstub_xtensa.c

@@ -24,6 +24,8 @@
 #warning "gdbstub_xtensa: revisit the implementation for Call0 ABI"
 #endif
 
+extern int _invalid_pc_placeholder;
+
 static void init_regfile(esp_gdbstub_gdb_regfile_t *dst)
 {
     memset(dst, 0, sizeof(*dst));
@@ -32,7 +34,7 @@ static void init_regfile(esp_gdbstub_gdb_regfile_t *dst)
 static void update_regfile_common(esp_gdbstub_gdb_regfile_t *dst)
 {
     if (dst->a[0] & 0x8000000U) {
-        dst->a[0] = (dst->a[0] & 0x3fffffffU) | 0x40000000U;
+        dst->a[0] = (uint32_t)cpu_ll_pc_to_ptr(dst->a[0]);
     }
     if (!esp_stack_ptr_is_sane(dst->a[1])) {
         dst->a[1] = 0xDEADBEEF;
@@ -47,7 +49,15 @@ void esp_gdbstub_frame_to_regfile(const esp_gdbstub_frame_t *frame, esp_gdbstub_
 {
     init_regfile(dst);
     const uint32_t *a_regs = (const uint32_t *) &frame->a0;
-    dst->pc = (frame->pc & 0x3fffffffU) | 0x40000000U;
+    if (!(esp_ptr_executable(cpu_ll_pc_to_ptr(frame->pc)) && (frame->pc & 0xC0000000U))) {
+        /* Xtensa ABI sets the 2 MSBs of the PC according to the windowed call size
+         * Incase the PC is invalid, GDB will fail to translate addresses to function names
+         * Hence replacing the PC to a placeholder address in case of invalid PC
+         */
+        dst->pc = (uint32_t)&_invalid_pc_placeholder;
+    } else {
+        dst->pc = (uint32_t)cpu_ll_pc_to_ptr(frame->pc);
+    }
 
     for (int i = 0; i < 16; i++) {
         dst->a[i] = a_regs[i];
@@ -73,7 +83,11 @@ static void solicited_frame_to_regfile(const XtSolFrame *frame, esp_gdbstub_gdb_
 {
     init_regfile(dst);
     const uint32_t *a_regs = (const uint32_t *) &frame->a0;
-    dst->pc = (frame->pc & 0x3fffffffU) | 0x40000000U;
+    if (!(esp_ptr_executable(cpu_ll_pc_to_ptr(frame->pc)) && (frame->pc & 0xC0000000U))) {
+        dst->pc = (uint32_t)&_invalid_pc_placeholder;
+    } else {
+        dst->pc = (uint32_t)cpu_ll_pc_to_ptr(frame->pc);
+    }
 
     /* only 4 registers saved in the solicited frame */
     for (int i = 0; i < 4; i++) {

components/esp_system/port/panic_handler.c

@@ -51,7 +51,9 @@
 
 #include "panic_internal.h"
 
-extern void esp_panic_handler(panic_info_t *);
+extern int _invalid_pc_placeholder;
+
+extern void esp_panic_handler(panic_info_t*);
 
 static wdt_hal_context_t wdt0_context = {.inst = WDT_MWDT0, .mwdt_dev = &TIMERG0};
 
@@ -512,6 +514,13 @@ static void panic_handler(XtExcFrame *frame, bool pseudo_excause)
 #endif
 
     if (esp_cpu_in_ocd_debug_mode()) {
+        if (!(esp_ptr_executable(cpu_ll_pc_to_ptr(frame->pc)) && (frame->pc & 0xC0000000U))) {
+            /* Xtensa ABI sets the 2 MSBs of the PC according to the windowed call size
+             * Incase the PC is invalid, GDB will fail to translate addresses to function names
+             * Hence replacing the PC to a placeholder address in case of invalid PC
+             */
+            frame->pc = (uint32_t)&_invalid_pc_placeholder;
+        }
         if (frame->exccause == PANIC_RSN_INTWDT_CPU0 ||
                 frame->exccause == PANIC_RSN_INTWDT_CPU1) {
             wdt_hal_write_protect_disable(&wdt0_context);

components/soc/src/esp32/include/hal/cpu_ll.h

@@ -103,7 +103,7 @@ static inline uint32_t cpu_ll_ptr_to_pc(const void* addr)
 
 static inline void* cpu_ll_pc_to_ptr(uint32_t pc)
 {
-    return (void*) ((pc & 0x3fffffff) | 0x40000000);
+    return (void*) ((pc & 0x3fffffffU) | 0x40000000U);
 }
 
 static inline void cpu_ll_set_watchpoint(int id,

components/soc/src/esp32s2/include/hal/cpu_ll.h

@@ -97,7 +97,7 @@ static inline uint32_t cpu_ll_ptr_to_pc(const void* addr)
 
 static inline void* cpu_ll_pc_to_ptr(uint32_t pc)
 {
-    return (void*) ((pc & 0x3fffffff) | 0x40000000);
+    return (void*) ((pc & 0x3fffffffU) | 0x40000000U);
 }
 
 static inline void cpu_ll_set_watchpoint(int id,