James Greenhalgh writes:

> Hi Jiong,
>
> I was looking at another bug and in the process of auditing our code
> spotted an issue with this patch from back in June...
>
> On Fri, Jun 19, 2015 at 10:15:38AM +0100, Jiong Wang wrote:
>> diff --git a/gcc/config/aarch64/aarch64.md b/gcc/config/aarch64/aarch64.md
>> index 8b061ba..be9da5b 100644
>> --- a/gcc/config/aarch64/aarch64.md
>> +++ b/gcc/config/aarch64/aarch64.md
>> +(define_insn "tlsie_tiny_sidi"
>> +  [(set (match_operand:DI 0 "register_operand" "=&r")
>> +	(zero_extend:DI
>> +          (unspec:SI [(match_operand 1 "aarch64_tls_ie_symref" "S")
>> +		      (match_operand:DI 2 "register_operand" "r")
>> +		      ]
>> +		      UNSPEC_GOTTINYTLS)))]
>> +  ""
>> +  "ldr\\t%w0, %L1\;add\\t%<w>0, %<w>0, %<w>2"
>
> Here, you have no iterators, so the <w> will never be replaced. Consequently,
> you are likely to hit an ICE if this pattern is ever used.
>
> I presume you intended this to say
>
>   "ldr\\t%w0, %L1\;add\\t%w0, %w0, %w2"
>
> If so, consider that change preapproved.

Thanks, yes, it's a hiding bug which might be triggered under ILP32 mode
only.

committed below patch after bootstrap & regression tls* testcases OK.


2015-10-05 James Greenhalgh <james.greenhalgh@arm.com>
           Jiong Wang  <jiong.wang@arm.com>

gcc/
  * config/aarch64/aarch64.md (tlsie_tiny_sidi): Replace "<w>" with "w".