ARMCompiler6.18 armasm inline assembly syntax

I tried to switch my compiler from ARM V5 to V6, and I faced a inline assembly funciton conversion issue:


DATA_RAM_FUNCTION __asm void prvEnableVFP_RTT(void)
    /* The FPU enable bits are in the CPACR. */
    ldr.w r0, = 0xE000ED88
    ldr r1, [r0]
    /* Enable CP10 and CP11 coprocessors, then save back. */
    // orr r1, r1, #( 0xf << 20 )
    orr r1, r1, #0xf00000
    str r1, [r0]
    bx r14

[After Conversion]

DATA_RAM_FUNCTION void prvEnableVFP_RTT(void)
    __asm volatile(
    ".eabi_attribute Tag_ABI_align_preserved, 1 \n"
    "ldr.w r0, = %0 \n"
    "ldr r1, [r0] \n"
    "orr r1, r1, #0xf00000 \n"
    "str r1, [r0] \n"
    "bx r14 \n"
    "nop \n"
    : /* no outputs */ : "r"(0xE000ED88) : "r0", "r1", "r14"

There is a error:

./.rtt-studio/Debug\rtthread.axf: Error: L6218E: Undefined symbol r2 (referred from lto-llvm-293411.o).

What's going wrong?