Hello On Mon, May 11, 2020 at 10:35 PM Thomas Gleixner <t...@linutronix.de> wrote: > > Lai, > > Lai Jiangshan <jiangshanlai+l...@gmail.com> writes: > > On Tue, May 5, 2020 at 10:23 PM Thomas Gleixner <t...@linutronix.de> wrote: > >> +SYM_CODE_START(irq_entries_start) > >> + vector=FIRST_EXTERNAL_VECTOR > >> + .rept (FIRST_SYSTEM_VECTOR - FIRST_EXTERNAL_VECTOR) > >> + UNWIND_HINT_IRET_REGS > >> + .byte 0x6a, vector > >> + jmp common_interrupt > >> + .align 8 > >> + vector=vector+1 > >> + .endr > >> +SYM_CODE_END(irq_entries_start) > > > > Using ".byte 0x6a, vector" is somewhat ugly. > > > > I hope it should be " pushq $(s8_to_s64(vector))", which can also > > help to reduce bunches of comments about ".byte 0x6a, vector". > > > > However, I don't know how to implement s8_to_s64() here. > > Neither do I. > > > But at least the following code works (generates the same two-byte > > machine code as ".byte 0x6a, vector" does): > > > > .if vector < 128 > > pushq $(vector) > > .else > > pushq $(0xffffffffffffff00+vector) > > .endif > > Only slightly less ugly and needs as much commentry as the above.
Agree. Just FYI, I tried this later, it can work. #define S8_TO_S64(vector) ((vector>>7)*0xffffffffffffff00+vector) Thanks Lai
