From 41e9564df650ddedbdab27283ebcb0173adf024f Mon Sep 17 00:00:00 2001
From: Peter Maydell <peter.maydell@linaro.org>
Date: Wed, 19 Oct 2011 16:14:05 +0000
Subject: [PATCH] target-arm: v6 media multiply space: UNDEF on unassigned
encodings
Clean up the decoding of the v6 media multiply space so that we UNDEF
on unassigned encodings rather than randomly interpreting them as
some instruction in this space.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
target-arm/translate.c | 24 ++++++++++++++++++++----
1 file changed, 20 insertions(+), 4 deletions(-)
diff --git a/target-arm/translate.c b/target-arm/translate.c
index 75c0ad413a..e99fc183b4 100644
--- a/target-arm/translate.c
+++ b/target-arm/translate.c
@@ -7569,11 +7569,16 @@ static void disas_arm_insn(CPUState * env, DisasContext *s)
}
break;
case 2: /* Multiplies (Type 3). */
- tmp = load_reg(s, rm);
- tmp2 = load_reg(s, rs);
- if (insn & (1 << 20)) {
+ switch ((insn >> 20) & 0x7) {
+ case 5:
+ if (((insn >> 6) ^ (insn >> 7)) & 1) {
+ /* op2 not 00x or 11x : UNDEF */
+ goto illegal_op;
+ }
/* Signed multiply most significant [accumulate].
(SMMUL, SMMLA, SMMLS) */
+ tmp = load_reg(s, rm);
+ tmp2 = load_reg(s, rs);
tmp64 = gen_muls_i64_i32(tmp, tmp2);
if (rd != 15) {
@@ -7592,7 +7597,15 @@ static void disas_arm_insn(CPUState * env, DisasContext *s)
tcg_gen_trunc_i64_i32(tmp, tmp64);
tcg_temp_free_i64(tmp64);
store_reg(s, rn, tmp);
- } else {
+ break;
+ case 0:
+ case 4:
+ /* SMLAD, SMUAD, SMLSD, SMUSD, SMLALD, SMLSLD */
+ if (insn & (1 << 7)) {
+ goto illegal_op;
+ }
+ tmp = load_reg(s, rm);
+ tmp2 = load_reg(s, rs);
if (insn & (1 << 5))
gen_swap_half(tmp2);
gen_smul_dual(tmp, tmp2);
@@ -7625,6 +7638,9 @@ static void disas_arm_insn(CPUState * env, DisasContext *s)
}
store_reg(s, rn, tmp);
}
+ break;
+ default:
+ goto illegal_op;
}
break;
case 3:
--
2.30.2