diff options
Diffstat (limited to 'target-alpha/fpu_helper.c')
| -rw-r--r-- | target-alpha/fpu_helper.c | 32 |
1 files changed, 22 insertions, 10 deletions
diff --git a/target-alpha/fpu_helper.c b/target-alpha/fpu_helper.c index db523fbc30..ea1f2e22b9 100644 --- a/target-alpha/fpu_helper.c +++ b/target-alpha/fpu_helper.c @@ -104,16 +104,14 @@ void helper_ieee_input(CPUAlphaState *env, uint64_t val) uint64_t frac = val & 0xfffffffffffffull; if (exp == 0) { - /* Denormals without DNZ set raise an exception. */ - if (frac != 0 && !env->fp_status.flush_inputs_to_zero) { - arith_excp(env, GETPC(), EXC_M_UNF, 0); + /* Denormals without /S raise an exception. */ + if (frac != 0) { + arith_excp(env, GETPC(), EXC_M_INV, 0); } } else if (exp == 0x7ff) { /* Infinity or NaN. */ - /* ??? I'm not sure these exception bit flags are correct. I do - know that the Linux kernel, at least, doesn't rely on them and - just emulates the insn to figure out what exception to use. */ - arith_excp(env, GETPC(), frac ? EXC_M_INV : EXC_M_FOV, 0); + env->fpcr |= FPCR_INV; + arith_excp(env, GETPC(), EXC_M_INV, 0); } } @@ -124,16 +122,30 @@ void helper_ieee_input_cmp(CPUAlphaState *env, uint64_t val) uint64_t frac = val & 0xfffffffffffffull; if (exp == 0) { - /* Denormals without DNZ set raise an exception. */ - if (frac != 0 && !env->fp_status.flush_inputs_to_zero) { - arith_excp(env, GETPC(), EXC_M_UNF, 0); + /* Denormals without /S raise an exception. */ + if (frac != 0) { + arith_excp(env, GETPC(), EXC_M_INV, 0); } } else if (exp == 0x7ff && frac) { /* NaN. */ + env->fpcr |= FPCR_INV; arith_excp(env, GETPC(), EXC_M_INV, 0); } } +/* Input handing with software completion. Trap for denorms, unless DNZ + is set. If we try to support DNOD (which none of the produced hardware + did, AFAICS), we'll need to suppress the trap when FPCR.DNOD is set; + then the code downstream of that will need to cope with denorms sans + flush_input_to_zero. Most of it should work sanely, but there's + nothing to compare with. */ +void helper_ieee_input_s(CPUAlphaState *env, uint64_t val) +{ + if (unlikely(2 * val - 1 < 0x1fffffffffffffull) + && !env->fp_status.flush_inputs_to_zero) { + arith_excp(env, GETPC(), EXC_M_INV | EXC_M_SWC, 0); + } +} /* S floating (single) */ |