[PATCH v3 06/33] target/alpha: Mask IOV exception with INV for user-only

["Alex Bennée" <alex.bennee@linaro.org>]

From: Richard Henderson <richard.henderson@linaro.org>

The kernel masks the integer overflow exception with the
software invalid exception mask.  Include IOV in the set
of exception bits masked by fpcr_exc_enable.

Fixes the new float_convs test.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20190921043256.4575-7-richard.henderson@linaro.org>
---
 target/alpha/helper.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/target/alpha/helper.c b/target/alpha/helper.c
index 1b3479738b7..55d7274d946 100644
--- a/target/alpha/helper.c
+++ b/target/alpha/helper.c
@@ -58,6 +58,13 @@ void cpu_alpha_store_fpcr(CPUAlphaState *env, uint64_t val)
      */
     uint32_t soft_fpcr = alpha_ieee_swcr_to_fpcr(env->swcr) >> 32;
     fpcr |= soft_fpcr & (FPCR_STATUS_MASK | FPCR_DNZ);
+
+    /*
+     * The IOV exception is disabled by the kernel with SWCR_TRAP_ENABLE_INV,
+     * which got mapped by alpha_ieee_swcr_to_fpcr to FPCR_INVD.
+     * Add FPCR_IOV to fpcr_exc_enable so that it is handled identically.
+     */
+    t |= CONVERT_BIT(soft_fpcr, FPCR_INVD, FPCR_IOV);
 #endif
 
     t |= CONVERT_BIT(fpcr, FPCR_INED, FPCR_INE);
-- 
2.20.1