
Volume 3: Instruction Reference
3:109
fpmax
fpmax — Floating-point Parallel Maximum
Format:
(
qp
) fpmax.
sf f
1
=
f
2
,
f
3
Description:
The paired single precision values in the significands of FR
f
2
or FR
f
3
are compared. The
operands with the larger value is returned in the significand of FR
f
1
.
If the value of high (low) FR
f
3
is less than the value of high (low) FR
f
2
, high (low) FR
f
1
gets high (low) FR
f
2
. Otherwise high (low) FR
f
1
gets high (low) FR
f
3
.
If high (low) FR
f
2
or high (low) FR
f
3
is a NaN, high (low) FR
f
1
gets high (low) FR
f
3
.
The exponent field of FR
f
1
is set to the biased exponent for 2.0
63
(0x1003E) and the
sign field of FR
f
1
is set to positive (0).
If either FR
f
2
or FR
f
3
is NaTVal, FR
f
1
is set to NaTVal instead of the computed result.
This operation does not propagate NaNs the same way as other arithmetic
floating-point instructions. The Invalid Operation is signaled in the same manner as for
the
fpcmp.lt
operation.
The mnemonic values for
sf
are given in
.
Operation:
if (PR[
qp
]) {
fp_check_target_register(
f
1
);
if (tmp_isrcode = fp_reg_disabled(
f
1
,
f
2
,
f
3
, 0))
disabled_fp_register_fault(tmp_isrcode, 0);
if (fp_is_natval(FR[
f
2
]) || fp_is_natval(FR[
f
3
])) {
FR[
f
1
] = NATVAL;
} else {
fpminmax_exception_fault_check(
f
2
,
f
3
,
sf
, &tmp_fp_env);
if (fp_raise_fault(tmp_fp_env))
fp_exception_fault(fp_decode_fault(tmp_fp_env));
tmp_fr2 = tmp_right = fp_reg_read_hi(
f
2
);
tmp_fr3 = tmp_left = fp_reg_read_hi(
f
3
);
tmp_bool_res = fp_less_than(tmp_left, tmp_right);
tmp_res_hi = fp_single(tmp_bool_res ? tmp_fr2 : tmp_fr3);
tmp_fr2 = tmp_right = fp_reg_read_lo(
f
2
);
tmp_fr3 = tmp_left = fp_reg_read_lo(
f
3
);
tmp_bool_res = fp_less_than(tmp_left, tmp_right);
tmp_res_lo = fp_single(tmp_bool_res ? tmp_fr2 : tmp_fr3);
FR[
f
1
].significand = fp_concatenate(tmp_res_hi, tmp_res_lo);
FR[
f
1
].exponent = FP_INTEGER_EXP;
FR[
f
1
].sign = FP_SIGN_POSITIVE;
fp_update_fpsr(
sf
, tmp_fp_env);
}
fp_update_psr(
f
1
);
}
FP Exceptions:
Invalid Operation (V)
Denormal/Unnormal Operand (D)
Software Assist (SWA) fault
Содержание Itanium 9150M
Страница 1: ......
Страница 209: ...3 200 Volume 3 Instruction Reference padd Interruptions Illegal Operation fault...
Страница 301: ...3 292 Volume 3 Pseudo Code Functions Intel Itanium Architecture Software Developer s Manual Rev 2 3...
Страница 405: ...3 396 Volume 3 Resource and Dependency Semantics...
Страница 406: ...3 397 Intel Itanium Architecture Software Developer s Manual Rev 2 3 Index...
Страница 407: ...3 398 Intel Itanium Architecture Software Developer s Manual Rev 2 3...
Страница 419: ...INDEX Index 12 Index for Volumes 1 2 3 and 4...
Страница 420: ......