On 3/7/22 08:44, Alex Bennée wrote:
The instruction description says "It is loaded without rounding
errors." which implies we should have the widest rounding mode
possible.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/888
Signed-off-by: Alex Bennée <alex.ben...@linaro.org>
---
target/i386/tcg/fpu_helper.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/target/i386/tcg/fpu_helper.c b/target/i386/tcg/fpu_helper.c
index cdd8e9f947..d986fd5792 100644
--- a/target/i386/tcg/fpu_helper.c
+++ b/target/i386/tcg/fpu_helper.c
@@ -250,11 +250,15 @@ void helper_fildl_ST0(CPUX86State *env, int32_t val)
void helper_fildll_ST0(CPUX86State *env, int64_t val)
{
int new_fpstt;
+ FloatX80RoundPrec old = get_floatx80_rounding_precision(&env->fp_status);
+ set_floatx80_rounding_precision(floatx80_precision_x, &env->fp_status);
new_fpstt = (env->fpstt - 1) & 7;
env->fpregs[new_fpstt].d = int64_to_floatx80(val, &env->fp_status);
env->fpstt = new_fpstt;
env->fptags[new_fpstt] = 0; /* validate stack entry */
+
+ set_floatx80_rounding_precision(old, &env->fp_status);
}
Yep.
Need a similar fix for fildl_ST0, for the case floatx80_precision_s is currently set
(int32_t has more than the 23 bits of single-precision).
r~
