Re: [PATCH 00/22] plugins: Rewrite plugin code generation

[Pierrick Bouvier]

On 3/16/24 05:56, Richard Henderson wrote:
> As I mooted with Pierrick earlier this week:
>
> (1) Add a (trivial) mechanism for emitting code into
> the middle of the opcode sequence: tcg_ctx->emit_before_op.
>
> (2) Rip out all of the "empty" generation and "copy"
> to modify those sequences.  Replace with regular code
> generation once we know what values to place.
>
> There's probably still more cleanup that could be done:
>
> There seems to be a lot of artificial separation between
> plugins and the rest of the code base, even between
> plugins/api.c and plugins/core.c.
>
> I suspect that all of plugins could be moved into the
> build-once buckets.
>
>
> r~
>
>
> Richard Henderson (22):
>    tcg: Add TCGContext.emit_before_op
>    tcg: Make tcg/helper-info.h self-contained
>    tcg: Pass function pointer to tcg_gen_call*
>    plugins: Zero new qemu_plugin_dyn_cb entries
>    plugins: Move function pointer in qemu_plugin_dyn_cb
>    plugins: Create TCGHelperInfo for all out-of-line callbacks
>    plugins: Use emit_before_op for PLUGIN_GEN_AFTER_INSN
>    plugins: Use emit_before_op for PLUGIN_GEN_FROM_TB
>    plugins: Add PLUGIN_GEN_AFTER_TB
>    plugins: Use emit_before_op for PLUGIN_GEN_FROM_INSN
>    plugins: Use emit_before_op for PLUGIN_GEN_FROM_MEM
>    plugins: Remove plugin helpers
>    tcg: Remove TCG_CALL_PLUGIN
>    tcg: Remove INDEX_op_plugin_cb_{start,end}
>    plugins: Simplify callback queues
>    plugins: Introduce PLUGIN_CB_MEM_REGULAR
>    plugins: Replace pr_ops with a proper debug dump flag
>    plugins: Split out common cb expanders
>    plugins: Merge qemu_plugin_tb_insn_get to plugin-gen.c
>    plugins: Move qemu_plugin_insn_cleanup_fn to tcg.c
>    plugins: Inline plugin_gen_empty_callback
>    plugins: Update the documentation block for plugin-gen.c
>
>   accel/tcg/plugin-helpers.h         |    5 -
>   include/exec/helper-gen-common.h   |    4 -
>   include/exec/helper-proto-common.h |    4 -
>   include/exec/plugin-gen.h          |    4 -
>   include/qemu/log.h                 |    1 +
>   include/qemu/plugin.h              |   79 +--
>   include/tcg/helper-info.h          |    3 +
>   include/tcg/tcg-op-common.h        |    4 +-
>   include/tcg/tcg-opc.h              |    4 +-
>   include/tcg/tcg.h                  |   27 +-
>   include/exec/helper-gen.h.inc      |   24 +-
>   accel/tcg/plugin-gen.c             | 1008 +++++++---------------------
>   plugins/api.c                      |   26 +-
>   plugins/core.c                     |   61 +-
>   tcg/tcg-op-ldst.c                  |    6 +-
>   tcg/tcg-op.c                       |    8 +-
>   tcg/tcg.c                          |  104 ++-
>   util/log.c                         |    4 +
>   18 files changed, 424 insertions(+), 952 deletions(-)
>   delete mode 100644 accel/tcg/plugin-helpers.h

Really great series. Not only the final code is much simpler, but it's 
faster as well (from the few tests I ran).