Segher Boessenkool wrote:
On Wed, Aug 31, 2022 at 12:50:07PM +0000, Christophe Leroy wrote:
Le 29/08/2022 à 07:52, Sathvika Vasireddy a écrit :
> + opcode = insn >> 26;
> +
> + switch (opcode) {
> + case 18: /* bl */
case 18 is more than 'bl', it includes also 'b'.
In both cases, the calculation of *immediate is the same.
It also is "ba" and "bla", sometimes written as "b[l][a]".
It would therefore be more correct to perform the calculation and setup
of *immediate outside the 'if ((insn & 3) == 1)', that would avoid
unnecessary churn the day we add support for branches without link.
Yeah, and probably move the comments around:
+ case 18: /* b[l][a] */
+ if ((insn & 3) == 1) { /* bl */
> + if ((insn & 3) == 1) {
> + *type = INSN_CALL;
> + *immediate = insn & 0x3fffffc;
> + if (*immediate & 0x2000000)
> + *immediate -= 0x4000000;
> + }
> + break;
> + }
Does this handle AA=1 correctly at all? That is valid both with and
without relocations, just like AA=0. Same for AA=1 LK=0 btw.
If you only handle AA=0, the code should explicitly test for that.
The code does test for AA=0 LK=1 with the if statement there?
- Naveen
