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Re: PATCH: PR gas/14859: Redundant ASP generated for jecxz


On Tue, Nov 20, 2012 at 6:44 AM, Jan Beulich <JBeulich@suse.com> wrote:
>>>> On 20.11.12 at 15:33, "H.J. Lu" <hjl.tools@gmail.com> wrote:
>> --- a/opcodes/i386-opc.tbl
>> +++ b/opcodes/i386-opc.tbl
>> @@ -390,7 +390,7 @@ jg, 1, 0x7f, None, 1, 0, Jump|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf|No_ldSuf,
>>  // jcxz vs. jecxz is chosen on the basis of the address size prefix.
>>  jcxz, 1, 0xe3, None, 1, CpuNo64, JumpByte|Size16|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf|No_ldSuf, { Disp8|Disp16|Disp32 }
>>  jecxz, 1, 0xe3, None, 1, CpuNo64, JumpByte|Size32|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf|No_ldSuf, { Disp8|Disp16|Disp32 }
>> -jecxz, 1, 0x67e3, None, 2, Cpu64, JumpByte|Size32|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf|No_ldSuf, { Disp8|Disp32|Disp32S }
>> +jecxz, 1, 0xe3, None, 1, Cpu64, JumpByte|Size32|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf|No_ldSuf, { Disp8|Disp32|Disp32S }
>
> I too had a fix for this pending, going a step further and folding
> the two jecxz entries into one (they're not meaningfully different
> anymore).
>

That is true.  We should fix all those insns which only take
8-bit displacement.

-- 
H.J.


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