Re: [PATCH v2] RISC-V: make C-extension JAL available again for (32-bit) assembly

[Jan Beulich <jbeulich@suse.com>]

On 31.01.2023 02:11, Nelson Chu wrote:
> Thanks for helping to follow these.

Well, it was my fault.

>  Looks reasonable, so please commit.

Done, also ..

> On Mon, Jan 30, 2023 at 10:07 PM Jan Beulich <jbeulich@suse.com> wrote:
>>
>> Along with the normal JAL alias, the C-extension one should have been
>> moved as well by 839189bc932e ("RISC-V: re-arrange opcode table for
>> consistent alias handling"), for the assembler to actually be able to
>> use it where/when possible.
>>
>> Since neither this nor any other compressed branch insn was being tested
>> so far, take the opportunity and introduce a new testcase covering those.
>> ---
>> Pretty clearly this should also go on the 2.40 branch.

... on to the branch.

>> --- a/gas/config/tc-riscv.c
>> +++ b/gas/config/tc-riscv.c
>> @@ -2764,6 +2764,8 @@ riscv_ip (char *str, struct riscv_cl_ins
>>                 case 'p':
>>                   goto branch;
>>                 case 'a':
>> +                 if (oparg == insn->args + 1)
>> +                   goto jump_check_gpr;
>>                   goto jump;
>>                 case 'S': /* Floating-point RS1 x8-x15.  */
>>                   if (!reg_lookup (&asarg, RCLASS_FPR, &regno)
>> @@ -3273,6 +3275,7 @@ riscv_ip (char *str, struct riscv_cl_ins
>>                  but the 2nd (with 2 operands) might.  */
>>               if (oparg == insn->args)
>>                 {
>> +           jump_check_gpr:
>>                   asargStart = asarg;
>>                   if (reg_lookup (&asarg, RCLASS_GPR, NULL)
>>                       && (*asarg == ',' || (ISSPACE (*asarg) && asarg[1] == ',')))

Just to mention it: I already have a patch to remove all this hackery
again, I just want to chew on it for a little more before posting, in
case I notice something that's wrong with the approach taken.

Jan