newlib: libc: aeabi_memmove M-profile PACBTI-enablement

Add function prologue/epilogue to conditionally add BTI landing pads
and/or PAC code generation & authentication instructions depending on
compilation flags.

newlib/libc/machine/arm/aeabi_memmove-thumb2.S

@@ -26,6 +26,8 @@
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include "arm_asm.h"
+
 	.thumb
 	.syntax unified
 	.global __aeabi_memmove
@@ -33,8 +35,10 @@
 	ASM_ALIAS __aeabi_memmove4 __aeabi_memmove
 	ASM_ALIAS __aeabi_memmove8 __aeabi_memmove
 __aeabi_memmove:
+	.fnstart
+	.cfi_startproc
+	prologue 4
 	cmp	r0, r1
-	push	{r4}
 	bls	3f
 	adds	r3, r1, r2
 	cmp	r0, r3
@@ -48,9 +52,10 @@ __aeabi_memmove:
 	strb	r4, [r1, #-1]!
 	bne	1b
 2:
-	pop	{r4}
-	bx	lr
+	.cfi_remember_state
+	epilogue 4
 3:
+	.cfi_restore_state
 	cmp	r2, #0
 	beq	2b
 	add	r2, r2, r1
@@ -60,6 +65,8 @@ __aeabi_memmove:
 	cmp	r2, r1
 	strb	r4, [r3, #1]!
 	bne	4b
-	pop	{r4}
-	bx	lr
+	epilogue 4
+	.cfi_endproc
+	.cantunwind
+	.fnend
 	.size __aeabi_memmove, . - __aeabi_memmove