[Qemu-devel] [PATCH 0/3] powerpc tcg backend improvements

[Richard Henderson <rth@twiddle.net>]

I happened to notice the ppc backend had a dependency on the placement
of the prologue, which has just changed.  There is a 32 byte window at
code_gen_buffer + 16MB where we might do the wrong thing.

The second patch reduces the code size reserved for performing goto_tb
from 7 insns to 4.  We probably haven't emitted all 7 insns for quite
some time, since the TCG_REG_RA patch went in.  But in the process,
allow for the atomic update of the insns, something that I could see
being required eventually.

The third patch is a guess.  But it matches the preferences in gcc,
giving out-of-order processors a tad more freedom by avoiding cr0
when possible.

Anyway, I've been running an alpha guest on a ppc64le host with these
patches for a week now.


r~


Richard Henderson (3):
  tcg/ppc: Adjust exit_tb for change in prologue placement
  tcg/ppc: Revise goto_tb implementation
  tcg/ppc: Prefer mask over andi.

 tcg/ppc/tcg-target.c | 79 ++++++++++++++++++++++++++++++++++------------------
 translate-all.c      |  2 ++
 2 files changed, 54 insertions(+), 27 deletions(-)

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2.4.3