On Wed, Feb 2, 2022 at 2:03 PM Philipp Tomsich <philipp.tomsich@vrull.eu> wrote:
>
>
> In adding our first X-extension (i.e., vendor-defined) on RISC-V with
> XVentanaCondOps, we need to add a few instructure improvements to make
> it easier to add similar vendor-defined extensions in the future:
> - refactor access to the cfg->ext_* fields by making a pointer to the
>   cfg structure (as cfg_ptr) available via DisasContext
> - add a table-based list of decoders to invoke, each being guarded by
>   a guard/predicate-function, that can be used to either add vendor
>   extensions, large extensions or override (by listing the decoder
>   before the one for standard extensions) patterns to handle errata
>
>
> Changes in v6:
> - add the 'vt' prefix to gen_condmask, renaming it to gen_vt_condmask
>
> Changes in v5:
> - use the typedef in DisasContext instead of the nakes struct
>   for RISCVCPUConfig
> - manually picked up those Reviewed-by tags from Richard that patman
>   missed
>
> Changes in v4:
> - use a typedef into 'RISCVCPUConfig' (instead of the explicit
>   'struct RISCVCPUConfig') to comply with the coding standard
>   (as suggested in Richard's review of v3)
> - add braces to comply with coding standard (as suggested by Richard)
> - merge the two if-statements to reduce clutter after (now that the
>   braces have been added)
>
> Changes in v3:
> - (new patch) refactor 'struct RISCVCPUConfig'
> - (new patch) copy pointer to element cfg into DisasContext
> - (new patch) test extension-availability through cfg_ptr in
>   DisasContext, removing the fields that have been copied into
>   DisasContext directly
> - (new patch) change Zb[abcs] implementation to use cfg_ptr (copied
>   into DisasContext) instead of going throuhg RISCV_CPU
> - expose only the DisasContext* to predicate functions
> - mark the table of decoder functions as static
> - drop the inline from always_true_p, until the need arises (i.e.,
>   someone finds a use for it and calls it directly)
> - rewrite to drop the 'handled' temporary in iterating over the
>   decoder table, removing the assignment in the condition of the if
> - rename to trans_xventanacondops.c.inc (i.e. with the '.c')
> - (in MATERIALISE_EXT_PREDICATE) don't annotate the predicate function
>   for testing the availability of individual extensions as 'inline'
>   and don't make CPURISCVState* visible to these predicate functions
> - add a MAINTAINERS entry for XVentanaCondOps
>
> Changes in v2:
> - (new patch) iterate over a table of guarded decoder functions
> - Split off decode table into XVentanaCondOps.decode
> - Wire up XVentanaCondOps in the decoder-table
>
> Philipp Tomsich (7):
>   target/riscv: refactor (anonymous struct) RISCVCPU.cfg into 'struct
>     RISCVCPUConfig'
>   target/riscv: riscv_tr_init_disas_context: copy pointer-to-cfg into
>     cfg_ptr
>   target/riscv: access configuration through cfg_ptr in DisasContext
>   target/riscv: access cfg structure through DisasContext
>   target/riscv: iterate over a table of decoders
>   target/riscv: Add XVentanaCondOps custom extension
>   target/riscv: add a MAINTAINERS entry for XVentanaCondOps

Thanks!

Applied to riscv-to-apply.next

Alistair

>
>  MAINTAINERS                                   |   7 ++
>  target/riscv/XVentanaCondOps.decode           |  25 +++++
>  target/riscv/cpu.c                            |   3 +
>  target/riscv/cpu.h                            |  81 +++++++-------
>  target/riscv/insn_trans/trans_rvb.c.inc       |   8 +-
>  target/riscv/insn_trans/trans_rvi.c.inc       |   2 +-
>  target/riscv/insn_trans/trans_rvv.c.inc       | 104 +++++++++---------
>  target/riscv/insn_trans/trans_rvzfh.c.inc     |   4 +-
>  .../insn_trans/trans_xventanacondops.c.inc    |  39 +++++++
>  target/riscv/meson.build                      |   1 +
>  target/riscv/translate.c                      |  60 ++++++----
>  11 files changed, 219 insertions(+), 115 deletions(-)
>  create mode 100644 target/riscv/XVentanaCondOps.decode
>  create mode 100644 target/riscv/insn_trans/trans_xventanacondops.c.inc
>
> --
> 2.33.1
>
>