weird behaviour during UC emulation

[ikanekb]

I have a function without epilogue nor prologue as a consequence of static inline. The IDA disassmebling of my function is :

Address Opcode Bytes Nnemonic
0xF80145C4 14 28 CMP R0, #0x14
0xF80145C6 01 DA BGE loc_F80145CC
0xF80145C8 05 48 LDR R0, =0x5A827999
0xF80145CA 70 47 BX LR
loc_F80145CC
0xF80145CC 28 28 CMP R0, #0x28
etc....

when I try to emulate with
a = Emu(UC_ARCH_ARM, UC_MODE_THUMB)
a.setTrace(TRACE_CODE)
a.eFunc(0xF80145C4 | 1, 0xF000000, [2])

the a.showTrace() show me:

Trace Instruction at 0xf80145c4, size = 4

Trace Instruction at 0xf805e61c, size = 4

Meaning that the instruction at 0xF80145C4 is interpreted as 4 bytes not 2 bytes.

Do you know why?

thx in advance