target-arm: A64: add support for 2-src data processing and DIV

This patch adds support for decoding 2-src data processing insns,
and the first users, UDIV and SDIV.

Signed-off-by: Alexander Graf <agraf@suse.de>
[claudio: adapted to new decoder adding the 2-src decoding level,
          always zero-extend result in 32bit mode]
Signed-off-by: Claudio Fontana <claudio.fontana@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>

1 files changed, 21 insertions, 0 deletions

diff --git a/target-arm/helper-a64.c b/target-arm/helper-a64.c
index adb8428105..abb98c00b5 100644
--- a/target-arm/helper-a64.c
+++ b/target-arm/helper-a64.c
@@ -23,3 +23,24 @@
 #include "qemu/host-utils.h"
 #include "sysemu/sysemu.h"
 #include "qemu/bitops.h"
+
+/* C2.4.7 Multiply and divide */
+/* special cases for 0 and LLONG_MIN are mandated by the standard */
+uint64_t HELPER(udiv64)(uint64_t num, uint64_t den)
+{
+    if (den == 0) {
+        return 0;
+    }
+    return num / den;
+}
+
+int64_t HELPER(sdiv64)(int64_t num, int64_t den)
+{
+    if (den == 0) {
+        return 0;
+    }
+    if (num == LLONG_MIN && den == -1) {
+        return LLONG_MIN;
+    }
+    return num / den;
+}