From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56980) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bB3Y7-0004bJ-Au for qemu-devel@nongnu.org; Thu, 09 Jun 2016 13:15:21 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bB3Y6-0008PW-9R for qemu-devel@nongnu.org; Thu, 09 Jun 2016 13:15:19 -0400 From: Peter Maydell Date: Thu, 9 Jun 2016 18:15:11 +0100 Message-Id: <1465492511-9333-1-git-send-email-peter.maydell@linaro.org> Subject: [Qemu-devel] [PATCH] target-arm: Don't permit ARMv8-only Neon insns on ARMv7 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-arm@nongnu.org, qemu-devel@nongnu.org Cc: patches@linaro.org, Christophe Lyon The Neon instructions VCVTA, VCVTM, VCVTN, VCVTP, VRINTA, VRINTM, VRINTN, VRINTP, VRINTX, and VRINTZ were only introduced with ARMv8, so they need a guard to make them UNDEF if the CPU only supports ARMv7. (We got this right for all the other new-in-v8 insns, but forgot it for these Neon 2-reg-misc ops.) Reported-by: Christophe Lyon Signed-off-by: Peter Maydell --- Christophe: I'd appreciate it if you could give this a quick test and confirm that it fixes the bug for you. target-arm/translate.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/target-arm/translate.c b/target-arm/translate.c index 6815bc1..3e71467 100644 --- a/target-arm/translate.c +++ b/target-arm/translate.c @@ -5311,6 +5311,30 @@ static int neon_2rm_is_float_op(int op) op >= NEON_2RM_VRECPE_F); } +static bool neon_2rm_is_v8_op(int op) +{ + /* Return true if this neon 2reg-misc op is ARMv8 and up */ + switch (op) { + case NEON_2RM_VRINTN: + case NEON_2RM_VRINTA: + case NEON_2RM_VRINTM: + case NEON_2RM_VRINTP: + case NEON_2RM_VRINTZ: + case NEON_2RM_VRINTX: + case NEON_2RM_VCVTAU: + case NEON_2RM_VCVTAS: + case NEON_2RM_VCVTNU: + case NEON_2RM_VCVTNS: + case NEON_2RM_VCVTPU: + case NEON_2RM_VCVTPS: + case NEON_2RM_VCVTMU: + case NEON_2RM_VCVTMS: + return true; + default: + return false; + } +} + /* Each entry in this array has bit n set if the insn allows * size value n (otherwise it will UNDEF). Since unallocated * op values will have no bits set they always UNDEF. @@ -6798,6 +6822,10 @@ static int disas_neon_data_insn(DisasContext *s, uint32_t insn) if ((neon_2rm_sizes[op] & (1 << size)) == 0) { return 1; } + if (neon_2rm_is_v8_op(op) && + !arm_dc_feature(s, ARM_FEATURE_V8)) { + return 1; + } if ((op != NEON_2RM_VMOVN && op != NEON_2RM_VQMOVN) && q && ((rm | rd) & 1)) { return 1; -- 1.9.1