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

[Peter Maydell <peter.maydell@linaro.org>]

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