target-arm: Fix saturated values for Neon right shifts

Fix value returned by signed 8 and 16 bit qrshl helpers
when the result has saturated.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>

diff --git a/target-arm/neon_helper.c b/target-arm/neon_helper.c
index c97aa7dbd430b7649d233a63850036baff3091a9..235a32c6704a52d29320c9d86db60533d263bc03 100644 (file)
--- a/target-arm/neon_helper.c
+++ b/target-arm/neon_helper.c
@@ -886,7 +886,10 @@ uint64_t HELPER(neon_qrshl_u64)(CPUState *env, uint64_t val, uint64_t shiftop)
         dest = src1 << tmp; \
         if ((dest >> tmp) != src1) { \
             SET_QC(); \
-            dest = src1 >> 31; \
+            dest = (uint32_t)(1 << (sizeof(src1) * 8 - 1)); \
+            if (src1 > 0) { \
+                dest--; \
+            } \
         } \
     }} while (0)
 NEON_VOP_ENV(qrshl_s8, neon_s8, 4)