arm/backtrace: add support for EHABI(Exception Handling ABI) stack unwinder

Reference:
https://github.com/ARM-software/abi-aa/blob/main/ehabi32/ehabi32.rst
https://github.com/ARM-software/abi-aa/releases/download/2022Q1/ehabi32.pdf

Signed-off-by: chao an <anchao@xiaomi.com>

arch/arm/Kconfig

@@ -1218,6 +1218,42 @@ config ARM_SEMIHOSTING_HOSTFS_CACHE_COHERENCE
 
 endif
 
+if SCHED_BACKTRACE
+
+choice
+	prompt "Choose ARM unwinder"
+	default UNWINDER_STACK_POINTER if ARM_THUMB
+	default UNWINDER_FRAME_POINTER if !ARM_THUMB
+	---help---
+		This determines which method will be used for unwinding nuttx stack
+		traces for debug.
+
+config UNWINDER_FRAME_POINTER
+	bool "Frame pointer unwinder"
+	select FRAME_POINTER
+	---help---
+		This option enables the frame pointer unwinder for unwinding
+		nuttx stack traces.
+
+config UNWINDER_STACK_POINTER
+	bool "Stack pointer unwinder"
+	---help---
+		This option enables the stack pointer unwinder for unwinding
+		nuttx stack traces.
+
+config UNWINDER_ARM
+	bool "ARM EHABI stack unwinder"
+	---help---
+		This option enables stack unwinding support in the nuttx
+		using the information automatically generated by the
+		compiler. The resulting nuttx image is slightly bigger but
+		the performance is not affected. Currently, this feature
+		only works with EABI compilers.
+
+endchoice
+
+endif
+
 if ARCH_ARMV6M
 source "arch/arm/src/armv6-m/Kconfig"
 endif

arch/arm/src/common/Make.defs

@@ -63,16 +63,16 @@ ifeq ($(CONFIG_SCHED_THREAD_LOCAL),y)
   CMN_CSRCS += arm_tls.c
 endif
 
-ifeq ($(CONFIG_SCHED_BACKTRACE),y)
+ifeq ($(CONFIG_UNWINDER_FRAME_POINTER),y)
-  ifeq ($(CONFIG_FRAME_POINTER),y)
+  CMN_CSRCS += arm_backtrace_fp.c
-    ifeq ($(CONFIG_ARM_THUMB),y)
+endif
-      CMN_CSRCS += arm_backtrace_thumb.c
+
-    else
+ifeq ($(CONFIG_UNWINDER_STACK_POINTER),y)
-      CMN_CSRCS += arm_backtrace_fp.c
+  CMN_CSRCS += arm_backtrace_thumb.c
-    endif
+endif
-  else
+
-    CMN_CSRCS += arm_backtrace_thumb.c
+ifeq ($(CONFIG_UNWINDER_ARM),y)
-  endif
+  CMN_CSRCS += arm_backtrace_unwind.c
 endif
 
 CMN_ASRCS += vfork.S

arch/arm/src/common/Toolchain.defs

@@ -74,6 +74,10 @@ ifeq ($(CONFIG_ARM_THUMB),y)
   ARCHOPTIMIZATION += -mthumb
 endif
 
+ifeq ($(CONFIG_UNWINDER_ARM),y)
+  ARCHOPTIMIZATION += -funwind-tables -fasynchronous-unwind-tables
+endif
+
 # Link Time Optimization
 
 ifeq ($(CONFIG_LTO_THIN),y)