enhanced stack trace decoder for ESP8266 plus minor fixes on the ESP32 side (mostly for consistency). This also updates gdb_hooks to include the register dump into the portion the user is to copy in to the stack trace decoder (#3013)

plus minor fixes on the ESP32 side (mostly for consistency). This also updates gdb_hooks to include the register dump into the portion the user is to copy in to the stack trace decoder

- decoder now includes the register dump, showing the different memory areas color coded to allow quick distinction of code/data addresses
- if possible shows a symbol / code line decode of addresses in the register file
- shows c/c++ context from the source file
- shows assembly context (only after the offending instruction)
- provides the same color coded addresses in the hex stack trace
- shows a list of functions on the stack 
- shows a list of data addresses / labels on the stack

The output, when used interactively, uses a pager and the input now requires to mark the end of the input by ^D (what was necessary to not get mixed lines in the output)

I did change the gdb_hooks.cpp file to 
- define the FSTRING values in a central place but use them in both the `gdbstub_exception_handler_flash()` and `dumpExceptionInfo()` functions. This might not be the most elegant way, but with the `=======` lines only wrapping around the actual stack dump, the guidance is confusing for the user and they would probably not copy the register file

Author: pljakobs

Sming/Arch/Esp32/Tools/decode-stacktrace.py

@@ -31,10 +31,12 @@ class Colors:
     GRAY = "\033[90m"
     LIGHT_BLUE = "\033[94m" # Labels
 
+CANARY_VALUES = {0xDEADBEEF, 0xA5A5A5A5, 0xFEFEFEFE, 0xABABABAB, 0x55AA55AA, 0xAA55AA55}
+
 def getAddrColor(val):
     """Return ANSI color code based on memory region."""
     # Stack Canary / Poison values
-    if val in [0xDEADBEEF, 0xA5A5A5A5, 0xFEFEFEFE, 0xABABABAB]:
+    if val in CANARY_VALUES:
         return Colors.RED
 
     # Based on typical ESP32 memory map
@@ -50,6 +52,16 @@ def getAddrColor(val):
     else:
         return Colors.RESET
 
+def colorizeHex(line):
+    """Colorize 0x-prefixed hex values in a line using getAddrColor."""
+    def replacer(m):
+        s = m.group(0)
+        try:
+            return f"{getAddrColor(int(s, 16))}{s}{Colors.RESET}"
+        except Exception:
+            return s
+    return re.sub(r'0x[0-9a-fA-F]+', replacer, line)
+
 def getElfSha256(filepath):
     """Calculate SHA256 of the ELF file to match against dump info."""
     try:
@@ -273,7 +285,7 @@ def disassemble(self, addr, count=6):
         try:
              res = subprocess.run(cmd, stdout=subprocess.PIPE, stderr=subprocess.DEVNULL, text=True)
              if res.returncode == 0:
-                  print(f"\n  {Colors.BOLD}Disassembly around {Colors.GREEN}0x{start:x}{Colors.RESET}:")
+                  print(f"\n  {Colors.BOLD}Disassembly around {getAddrColor(start)}0x{start:x}{Colors.RESET}:")
                   lines = res.stdout.splitlines()
                   for line in lines:
                       # Typical objdump line: "400d3f28:	00413603          	l32u	a2,4(sp)"
@@ -405,7 +417,7 @@ def flushRegisters(self):
                     if name in ["MEPC", "PC", "EPC"] and res and " at " in res:
                         # Extract File:Line
                         # Format: func at file:line
-                        m = re.search(r' at (.*):(\d+)', res)
+                        m = re.search(r' at (.*?):(\d+)', res)
                         if m:
                             sourceContextCandidate = (m.group(1), int(m.group(2)))
 
@@ -437,7 +449,17 @@ def flushRegisters(self):
              self.displaySourceContext(sourceContextCandidate[0], sourceContextCandidate[1])
 
         if targetDisasmAddr:
-            self.disassemble(targetDisasmAddr)
+            if 0x40000000 <= targetDisasmAddr < 0x50000000:
+                self.disassemble(targetDisasmAddr)
+            else:
+                if 0x30000000 <= targetDisasmAddr < 0x40000000:
+                    region = "Data (DRAM/DROM)"
+                elif 0x50000000 <= targetDisasmAddr < 0x60000000:
+                    region = "External SPI RAM"
+                else:
+                    region = "unknown region"
+                print(f"\n  {Colors.RED}PC/EPC (0x{targetDisasmAddr:08x}) is in {region} — execution jumped to non-code memory.{Colors.RESET}")
+                print(f"  {Colors.RED}No code can be disassembled here. Likely a wild pointer or stack corruption.{Colors.RESET}")
 
         print("") # clean separation
         self.registerBuffer = []
@@ -474,7 +496,7 @@ def colorReplacer(match):
             addrColored = f"{getAddrColor(val)}{addrStr}{Colors.RESET}"
 
             # Check for canary/poison
-            if val in [0xDEADBEEF, 0xA5A5A5A5, 0xFEFEFEFE, 0xABABABAB]:
+            if val in CANARY_VALUES:
                 # Commit current frame
                 if frameFuncs:
                     funcsFound.append((currentFrame, frameFuncs))
@@ -614,7 +636,7 @@ def processLine(self, line):
             # If we just entered IN_REGISTERS from IDLE above, we already printed the header.
             # But if we are continuing:
             if not isRegStart and not self.interactive: # Don't reprint header if we handled it in IDLE
-                 print(rawLine, end='')
+                 print(colorizeHex(rawLine), end='')
 
             # Parse registers: "Name : 0xVal"
             # PC      : 0x400d1f28  PS      : 0x00060830
@@ -651,6 +673,13 @@ def main():
 
     elfFile = sys.argv[1]
 
+    # Architecture guard
+    arch = os.environ.get('SMING_ARCH', '')
+    if arch and arch.lower() != 'esp32':
+        print(f"Error: SMING_ARCH='{arch}' but this is the ESP32 decoder.", file=sys.stderr)
+        print(f"Use the {arch} decoder instead (Sming/Arch/{arch}/Tools/decode-stacktrace.py).", file=sys.stderr)
+        sys.exit(1)
+
     # Tool Selection
     soc = os.environ.get('SMING_SOC', 'esp32').lower()
     if soc in ['esp32s2', 'esp32s3']:

Sming/Arch/Esp8266/Components/gdbstub/appcode/gdb_hooks.cpp

@@ -34,20 +34,19 @@ static PGM_P const exceptionNames[] PROGMEM = {
 	SYSTEM_EXCEPTION_MAP(XX)
 #undef XX
 };
-
+	
 // The asm stub saves the Xtensa registers here when an exception is raised
 GdbstubSavedRegisters gdbstub_savedRegs;
 
+DEFINE_PSTR_LOCAL(instructions_pstr, "To decode the stack dump call from command line:\r\n"
+									 "   make decode-stacktrace\r\n"
+									 "and copy & paste the text enclosed in '===='.\r\n");
+DEFINE_PSTR_LOCAL(separatorLine_pstr, "\n================================================================\r\n");
+
 void debug_print_stack(uint32_t start, uint32_t end)
 {
 	m_puts(_F("\r\n"
 			  "Stack dump:\r\n"));
-	PSTR_ARRAY(instructions, "To decode the stack dump call from command line:\r\n"
-							 "   make decode-stacktrace\r\n"
-							 "and copy & paste the text enclosed in '===='.\r\n");
-	PSTR_ARRAY(separatorLine, "\n================================================================\r\n");
-	m_puts(instructions);
-	m_puts(separatorLine);
 	for(uint32_t addr = start; addr < end; addr += 0x10) {
 		uint32_t* values = (uint32_t*)addr;
 		// rough indicator: stack frames usually have SP saved as the second word
@@ -59,13 +58,14 @@ void debug_print_stack(uint32_t start, uint32_t end)
 		system_soft_wdt_feed();
 		wdt_feed();
 	}
-	m_puts(separatorLine);
-	m_puts(instructions);
+
 }
 
 void debug_crash_callback([[maybe_unused]] const rst_info* rst_info, [[maybe_unused]] uint32_t stack,
 						  [[maybe_unused]] uint32_t stack_end)
 {
+	LOAD_PSTR(instructions, instructions_pstr);
+	LOAD_PSTR(separatorLine, separatorLine_pstr);
 #ifdef ENABLE_GDB
 	gdbFlushUserData();
 	if(gdb_state.attached) {
@@ -74,6 +74,9 @@ void debug_crash_callback([[maybe_unused]] const rst_info* rst_info, [[maybe_unu
 #endif
 
 #if defined(ENABLE_GDB) || ENABLE_CRASH_DUMP
+	m_puts(instructions);
+	m_puts(separatorLine);
+
 	switch(rst_info->reason) {
 	case REASON_EXCEPTION_RST:
 		m_printf(_F("\r\n"
@@ -100,14 +103,20 @@ void debug_crash_callback([[maybe_unused]] const rst_info* rst_info, [[maybe_unu
 #elif ENABLE_CRASH_DUMP
 	debug_print_stack(stack, stack_end);
 #endif
-
+	m_puts(separatorLine);
+	m_puts(instructions);
 #endif // defined(ENABLE_GDB) || ENABLE_CRASH_DUMP
 }
 
 #ifdef HOOK_SYSTEM_EXCEPTIONS
 
 void dumpExceptionInfo()
 {
+	LOAD_PSTR(instructions, instructions_pstr);
+	LOAD_PSTR(separatorLine, separatorLine_pstr);
+	m_puts(instructions);
+	m_puts(separatorLine);
+
 	auto& reg = gdbstub_savedRegs;
 
 	m_printf(_F("\r\n"
@@ -138,6 +147,8 @@ void dumpExceptionInfo()
 	if(gdb_present() != eGDB_Attached) {
 		debug_print_stack(reg.a[1], 0x3fffffb0);
 	}
+	m_puts(separatorLine);
+	m_puts(instructions);
 }
 
 // Main exception handler code