On 10/9/23 05:48, Richard W.M. Jones wrote:
RISCV_CPU(cs) uses a checked cast.  When QOM cast debugging is enabled
this adds about 5% total overhead when emulating RV64 on x86-64 host.

Using a RISC-V guest with 16 vCPUs, 16 GB of guest RAM, virtio-blk
disk.  The guest has a copy of the qemu source tree.  The test
involves compiling the qemu source tree with 'make clean; time make -j16'.

Before making this change the compile step took 449 & 447 seconds over
two consecutive runs.

After making this change: 428 & 421 seconds.

The saving is over 5%.

Thanks: Paolo Bonzini
Thanks: Philippe Mathieu-Daudé
Signed-off-by: Richard W.M. Jones <rjo...@redhat.com>
---
  target/riscv/cpu_helper.c | 3 +--
  1 file changed, 1 insertion(+), 2 deletions(-)

Reviewed-by: Richard Henderson <richard.hender...@linaro.org>


r~

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