llext: add movt/movw relocation test

Arch arm relocatate test covers:
R_ARM_ABS32: all tests
decode_thm_jumps -> relative jmp extension
decode_thm_movs -> movwmovt extension

Signed-off-by: Cedric Lescop <cedric.lescop@se.com>

tests/subsys/llext/simple/CMakeLists.txt

@@ -17,7 +17,7 @@ target_include_directories(app PRIVATE
 
 if(NOT LOADER_BUILD_ONLY)
 # generate extension targets foreach extension given by name
-foreach(ext_name hello_world logging relative_jump object)
+foreach(ext_name hello_world logging relative_jump object movwmovt)
   set(ext_src ${PROJECT_SOURCE_DIR}/src/${ext_name}_ext.c)
   set(ext_bin ${ZEPHYR_BINARY_DIR}/${ext_name}.llext)
   set(ext_inc ${ZEPHYR_BINARY_DIR}/include/generated/${ext_name}.inc)

tests/subsys/llext/simple/src/movwmovt_ext.c

@@ -0,0 +1,32 @@
+/*
+ * Copyright (c) 2024 Schneider Electric.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/*
+ * This test is designed to test MOV.W and MOV.T instructions on ARM architectures.
+ * (except M0 & M0+, not supported)
+ */
+
+#include <stdint.h>
+#include <zephyr/llext/symbol.h>
+#include <zephyr/sys/printk.h>
+
+
+static void test_func(void)
+{
+	printk("%s\n", __func__);
+}
+
+void test_entry(void)
+{
+	test_func();
+#if defined(CONFIG_ARM) && !defined(CONFIG_CPU_CORTEX_M0) && !defined(CONFIG_CPU_CORTEX_M0PLUS)
+	printk("test movwmovt\n");
+	__asm volatile ("movw r0, #:lower16:test_func");
+	__asm volatile ("movt r0, #:upper16:test_func");
+	__asm volatile ("blx r0");
+#endif
+}
+LL_EXTENSION_SYMBOL(test_entry);

tests/subsys/llext/simple/src/test_llext_simple.c

@@ -160,6 +160,13 @@ static LLEXT_CONST uint8_t object_ext[] __aligned(4) = {
 LLEXT_LOAD_UNLOAD(object, true)
 #endif /* ! LOADER_BUILD_ONLY */
 
+#if defined(CONFIG_ARM) && !defined(CONFIG_CPU_CORTEX_M0) && !defined(CONFIG_CPU_CORTEX_M0PLUS)
+static LLEXT_CONST uint8_t movwmovt_ext[] __aligned(4) = {
+	#include "movwmovt.inc"
+};
+LLEXT_LOAD_UNLOAD(movwmovt, true)
+#endif
+
 /*
  * Ensure that EXPORT_SYMBOL does indeed provide a symbol and a valid address
  * to it.