diff options
| author | Peter Maydell <peter.maydell@linaro.org> | 2020-08-06 11:44:52 +0100 |
|---|---|---|
| committer | Peter Maydell <peter.maydell@linaro.org> | 2020-08-24 10:15:11 +0100 |
| commit | aaae563bc73de0598bbc09a102e68f27fafe704a (patch) | |
| tree | c2362da0fd9d29b9f9469947f60edae8ac4364a6 /target/arm/cpu.c | |
| parent | a84d1d1316726704edd2617b2c30c921d98a8137 (diff) | |
target/arm: Implement FPST_STD_F16 fpstatus
Architecturally, Neon FP16 operations use the "standard FPSCR" like
all other Neon operations. However, this is defined in the Arm ARM
pseudocode as "a fixed value, except that FZ16 (and AHP) follow the
FPSCR bits". In QEMU, the softfloat float_status doesn't include
separate flush-to-zero for FP16 operations, so we must keep separate
fp_status for "Neon non-FP16" and "Neon fp16" operations, in the
same way we do already for the non-Neon "fp_status" vs "fp_status_f16".
Add the extra float_status field to the CPU state structure,
ensure it is correctly initialized and updated on FPSCR writes,
and make fpstatus_ptr(FPST_STD_F16) return a pointer to it.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20200806104453.30393-4-peter.maydell@linaro.org
Diffstat (limited to 'target/arm/cpu.c')
| -rw-r--r-- | target/arm/cpu.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/target/arm/cpu.c b/target/arm/cpu.c index 111579554f..6b382fcd60 100644 --- a/target/arm/cpu.c +++ b/target/arm/cpu.c @@ -391,12 +391,15 @@ static void arm_cpu_reset(DeviceState *dev) set_flush_to_zero(1, &env->vfp.standard_fp_status); set_flush_inputs_to_zero(1, &env->vfp.standard_fp_status); set_default_nan_mode(1, &env->vfp.standard_fp_status); + set_default_nan_mode(1, &env->vfp.standard_fp_status_f16); set_float_detect_tininess(float_tininess_before_rounding, &env->vfp.fp_status); set_float_detect_tininess(float_tininess_before_rounding, &env->vfp.standard_fp_status); set_float_detect_tininess(float_tininess_before_rounding, &env->vfp.fp_status_f16); + set_float_detect_tininess(float_tininess_before_rounding, + &env->vfp.standard_fp_status_f16); #ifndef CONFIG_USER_ONLY if (kvm_enabled()) { kvm_arm_reset_vcpu(cpu); |