| Message ID | 20241202131347.498124-28-peter.maydell@linaro.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | fpu: Remove pickNaNMulAdd, default-NaN ifdefs | expand |
On 12/2/24 07:13, Peter Maydell wrote: > Currently m68k_cpu_reset_hold() calls floatx80_default_nan(NULL) > to get the NaN bit pattern to reset the FPU registers. This > works because it happens that our implementation of > floatx80_default_nan() doesn't actually look at the float_status > pointer except for TARGET_MIPS. However, this isn't guaranteed, > and to be able to remove the ifdef in floatx80_default_nan() > we're going to need a real float_status here. > > Rearrange m68k_cpu_reset_hold() so that we initialize env->fp_status > earlier, and thus can pass it to floatx80_default_nan(). > > Signed-off-by: Peter Maydell<peter.maydell@linaro.org> > --- > target/m68k/cpu.c | 12 +++++++----- > 1 file changed, 7 insertions(+), 5 deletions(-) Reviewed-by: Richard Henderson <richard.henderson@linaro.org> r~
diff --git a/target/m68k/cpu.c b/target/m68k/cpu.c index 5fe335558aa..13b76e22488 100644 --- a/target/m68k/cpu.c +++ b/target/m68k/cpu.c @@ -76,7 +76,7 @@ static void m68k_cpu_reset_hold(Object *obj, ResetType type) CPUState *cs = CPU(obj); M68kCPUClass *mcc = M68K_CPU_GET_CLASS(obj); CPUM68KState *env = cpu_env(cs); - floatx80 nan = floatx80_default_nan(NULL); + floatx80 nan; int i; if (mcc->parent_phases.hold) { @@ -89,10 +89,6 @@ static void m68k_cpu_reset_hold(Object *obj, ResetType type) #else cpu_m68k_set_sr(env, SR_S | SR_I); #endif - for (i = 0; i < 8; i++) { - env->fregs[i].d = nan; - } - cpu_m68k_set_fpcr(env, 0); /* * M68000 FAMILY PROGRAMMER'S REFERENCE MANUAL * 3.4 FLOATING-POINT INSTRUCTION DETAILS @@ -109,6 +105,12 @@ static void m68k_cpu_reset_hold(Object *obj, ResetType type) * preceding paragraph for nonsignaling NaNs. */ set_float_2nan_prop_rule(float_2nan_prop_ab, &env->fp_status); + + nan = floatx80_default_nan(&env->fp_status); + for (i = 0; i < 8; i++) { + env->fregs[i].d = nan; + } + cpu_m68k_set_fpcr(env, 0); env->fpsr = 0; /* TODO: We should set PC from the interrupt vector. */
Currently m68k_cpu_reset_hold() calls floatx80_default_nan(NULL) to get the NaN bit pattern to reset the FPU registers. This works because it happens that our implementation of floatx80_default_nan() doesn't actually look at the float_status pointer except for TARGET_MIPS. However, this isn't guaranteed, and to be able to remove the ifdef in floatx80_default_nan() we're going to need a real float_status here. Rearrange m68k_cpu_reset_hold() so that we initialize env->fp_status earlier, and thus can pass it to floatx80_default_nan(). Signed-off-by: Peter Maydell <peter.maydell@linaro.org> --- target/m68k/cpu.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-)