Re: [PATCH 0/2] target/ppc: Fix vextu[bhw][lr]x on big endian hosts

[Philippe Mathieu-Daudé]

On 8/24/21 10:11 PM, matheus.ferst@eldorado.org.br wrote:
> From: Matheus Ferst <matheus.ferst@eldorado.org.br>
> 
> The definition of struct Int128 is currently independent of the host
> endianness, causing different results when using the member s128 of
> union ppc_vsr_t in big-endian builds with CONFIG_INT128 or
> !CONFIG_INT128.
> 
> The only PPC instructions that seem to be affected by this issue are the
> "Vector Extract Unsigned Byte/Halfword/Word to GPR using GPR-specified
> Left/Right-Index." Even on builds with Int128 support, however, their
> helpers give the wrong result on big-endian hosts.
> 
> The first patch in this series changes the definition of struct Int128
> to allow its use in the ppc_vsr_t union. The second patch fixes the
> helper definition.
> 
> Matheus Ferst (2):
>   include/qemu/int128.h: define struct Int128 according to the host
>     endianness
>   target/ppc: fix vextu[bhw][lr]x helpers
> 
>  include/qemu/int128.h   | 19 ++++++++++++-------
>  target/ppc/int_helper.c | 38 ++++++++++----------------------------
>  2 files changed, 22 insertions(+), 35 deletions(-)

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>