1 files changed, 21 insertions, 0 deletions
diff --git a/tb/sim/modeswitch.S b/tb/sim/modeswitch.S
new file mode 100644
index 0000000..c04f8a3
--- /dev/null
+++ b/tb/sim/modeswitch.S
@@ -0,0 +1,21 @@
+.global reset
+reset:
+	mrs  r0, cpsr
+	udf
+	mrs  r2, cpsr
+	ldr  r3, =#0x16f
+	bic  r3, r2, r3
+	msr  cpsr_fxc, r3
+	mrs  r4, cpsr
+	cmp  r0, r0
+	mrs  r5, spsr
+	nop
+	msr  cpsr_fxc, r0 
+	msr  spsr_fxc, r0
+	mov  pc, lr
+
+.global undefined
+undefined:
+	mrs  r1, spsr
+	mrs  r13, cpsr
+	movs pc, lr