[Mono-dev] Global register allocator in JIT

[Zoltan Varga]

                          Hi,

  This is perfectly normal, the current burg phase sometimes introduces such
extra moves. What is the C#/IL from which this was generated ?

          Zoltan

On 10/10/06, Sergey Tikhonov <tsv at solvo.ru> wrote:
> Hello,
>
> I am trying to make global register allocator to work on Alpha mono
> port. It started to use dedicated global registers, but
> I could not get an idea how it supposed to work. For example:
> DUMP BLOCK 2:
>  (beq[B3B4] (compare (and (or (long_conv_to_i4 (ldind.i
> regvar[alpha_r12])) (long_conv_to_i4 (ldind.i regvar[alpha_r13])))
> iconst[3]) iconst[0]))
> uses alpha_r12 and alpha_r13 registers that hold args passed to a method
> (so far good). But this code is translated to:
> LOCAL REGALLOC: BASIC BLOCK: 2
>         1  move R34 <- alpha_r12
>         2  conv.i4 R33 <- R34
>         3  move R36 <- alpha_r13
>         4  conv.i4 R35 <- R36
>         5  int_or R32 <- R33 R35
>         6  int_and_imm R31 <- R32
>         7  alpha_cmp_imm_eq R31
>         8  int_bne_un
> Now it start to use local registers to do conv.i4 conversion. Why it can
> use allocated global regs as source regs for conv opcode?
> Should peephole pass to handle this? (but it would get complex :( ) How
> it should work?
>
> Thank you,
> Sergey.
>
> tsv at solvo.ru
> Solvo Ltd.
>
>
>
>