diff options
| -rw-r--r-- | target/ppc/fpu_helper.c | 32 |
1 files changed, 30 insertions, 2 deletions
diff --git a/target/ppc/fpu_helper.c b/target/ppc/fpu_helper.c index 07bc905..c8e7192 100644 --- a/target/ppc/fpu_helper.c +++ b/target/ppc/fpu_helper.c @@ -2887,12 +2887,40 @@ void helper_xscvqpdp(CPUPPCState *env, uint32_t opcode, uint64_t helper_xscvdpspn(CPUPPCState *env, uint64_t xb) { - uint64_t result; + uint64_t result, sign, exp, frac; float_status tstat = env->fp_status; set_float_exception_flags(0, &tstat); - result = (uint64_t)float64_to_float32(xb, &tstat); + sign = extract64(xb, 63, 1); + exp = extract64(xb, 52, 11); + frac = extract64(xb, 0, 52) | 0x10000000000000ULL; + + if (unlikely(exp == 0 && extract64(frac, 0, 52) != 0)) { + /* DP denormal operand. */ + /* Exponent override to DP min exp. */ + exp = 1; + /* Implicit bit override to 0. */ + frac = deposit64(frac, 53, 1, 0); + } + + if (unlikely(exp < 897 && frac != 0)) { + /* SP tiny operand. */ + if (897 - exp > 63) { + frac = 0; + } else { + /* Denormalize until exp = SP min exp. */ + frac >>= (897 - exp); + } + /* Exponent override to SP min exp - 1. */ + exp = 896; + } + + result = sign << 31; + result |= extract64(exp, 10, 1) << 30; + result |= extract64(exp, 0, 7) << 23; + result |= extract64(frac, 29, 23); + /* hardware replicates result to both words of the doubleword result. */ return (result << 32) | result; } |