[Qemu-devel] [RISU PATCH] arm.risu: Avoid VTRN with Vd == Vm

Peter Maydell posted 1 patch 4 years, 10 months ago
Failed in applying to current master (apply log)
arm.risu | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
[Qemu-devel] [RISU PATCH] arm.risu: Avoid VTRN with Vd == Vm
Posted by Peter Maydell 4 years, 10 months ago
The AArch32 VTRN instruction is specified to give an UNKNOWN
result if Vd and Vm are the same register; avoid generating
this in risu output, as we already do for VUZP and VZIP.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
Alex: this pattern error is why we don't pass your
testcases/aarch32-all/insn_VTRN__INC.risu.bin when compared
with a real Cortex-A7. You probably want to update that.

 arm.risu | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arm.risu b/arm.risu
index 9009e6b..c16d245 100644
--- a/arm.risu
+++ b/arm.risu
@@ -613,7 +613,8 @@ VCLT0 A1 1111 0011 1 d 11 sz:2 01 vd:4 0 f 100 q m 0 vm:4
 VABS A1 1111 0011 1 d 11 sz:2 01 vd:4 0 f 110 q m 0 vm:4
 VNEG A1 1111 0011 1 d 11 sz:2 01 vd:4 0 f 111 q m 0 vm:4
 VSWP A1 1111 0011 1 d 11 sz:2 10 vd:4 00000 q m 0 vm:4
-VTRN A1 1111 0011 1 d 11 sz:2 10 vd:4 00001 q m 0 vm:4
+# d == m gives UNKNOWN results, so avoid it
+VTRN A1 1111 0011 1 d 11 sz:2 10 vd:4 00001 q m 0 vm:4 { ($d != $m) || ($vd != $vm); }
 # d == m gives UNKNOWN results, so avoid it
 VUZP A1 1111 0011 1 d 11 sz:2 10 vd:4 00010 q m 0 vm:4 { ($d != $m) || ($vd != $vm); }
 VZIP A1 1111 0011 1 d 11 sz:2 10 vd:4 00011 q m 0 vm:4 { ($d != $m) || ($vd != $vm); }
-- 
2.20.1


Re: [Qemu-devel] [RISU PATCH] arm.risu: Avoid VTRN with Vd == Vm
Posted by Richard Henderson 4 years, 10 months ago
On 6/13/19 7:37 AM, Peter Maydell wrote:
> The AArch32 VTRN instruction is specified to give an UNKNOWN
> result if Vd and Vm are the same register; avoid generating
> this in risu output, as we already do for VUZP and VZIP.
> 
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
> Alex: this pattern error is why we don't pass your
> testcases/aarch32-all/insn_VTRN__INC.risu.bin when compared
> with a real Cortex-A7. You probably want to update that.
> 
>  arm.risu | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)

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


r~

Re: [Qemu-devel] [RISU PATCH] arm.risu: Avoid VTRN with Vd == Vm
Posted by Peter Maydell 4 years, 10 months ago
On Thu, 13 Jun 2019 at 22:17, Richard Henderson
<richard.henderson@linaro.org> wrote:
>
> On 6/13/19 7:37 AM, Peter Maydell wrote:
> > The AArch32 VTRN instruction is specified to give an UNKNOWN
> > result if Vd and Vm are the same register; avoid generating
> > this in risu output, as we already do for VUZP and VZIP.
> >
> > Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> > ---
> > Alex: this pattern error is why we don't pass your
> > testcases/aarch32-all/insn_VTRN__INC.risu.bin when compared
> > with a real Cortex-A7. You probably want to update that.
> >
> >  arm.risu | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
>
> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

Applied to risu master, thanks.

-- PMM