fpu: use min/max values from stdint.h for integral overflow

Remove some more use of LIT64 while making the meaning more clear. We
also avoid the need of casts as the results by definition fit into the
return type.

Backports commit 2c217da0fc9f1127bda804e2a500b8138b02c581 from qemu
This commit is contained in:
Alex Bennée 2019-11-18 20:45:38 -05:00 committed by Lioncash
parent 0d573763c9
commit 6eb3c9ee79
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@ -3362,7 +3362,7 @@ static int32_t roundAndPackInt32(flag zSign, uint64_t absZ, float_status *status
if ( zSign ) z = - z;
if ( ( absZ>>32 ) || ( z && ( ( z < 0 ) ^ zSign ) ) ) {
float_raise(float_flag_invalid, status);
return zSign ? (int32_t) 0x80000000 : 0x7FFFFFFF;
return zSign ? INT32_MIN : INT32_MAX;
}
if (roundBits) {
status->float_exception_flags |= float_flag_inexact;
@ -3422,9 +3422,7 @@ static int64_t roundAndPackInt64(flag zSign, uint64_t absZ0, uint64_t absZ1,
if ( z && ( ( z < 0 ) ^ zSign ) ) {
overflow:
float_raise(float_flag_invalid, status);
return
zSign ? (int64_t) LIT64( 0x8000000000000000 )
: LIT64( 0x7FFFFFFFFFFFFFFF );
return zSign ? INT64_MIN : INT64_MAX;
}
if (absZ1) {
status->float_exception_flags |= float_flag_inexact;
@ -3475,7 +3473,7 @@ static int64_t roundAndPackUint64(flag zSign, uint64_t absZ0,
++absZ0;
if (absZ0 == 0) {
float_raise(float_flag_invalid, status);
return LIT64(0xFFFFFFFFFFFFFFFF);
return UINT64_MAX;
}
absZ0 &= ~(((uint64_t)(absZ1<<1) == 0) & roundNearestEven);
}
@ -5497,9 +5495,9 @@ int64_t floatx80_to_int64(floatx80 a, float_status *status)
if ( shiftCount ) {
float_raise(float_flag_invalid, status);
if (!aSign || floatx80_is_any_nan(a)) {
return LIT64( 0x7FFFFFFFFFFFFFFF );
return INT64_MAX;
}
return (int64_t) LIT64( 0x8000000000000000 );
return INT64_MIN;
}
aSigExtra = 0;
}
@ -5540,10 +5538,10 @@ int64_t floatx80_to_int64_round_to_zero(floatx80 a, float_status *status)
if ( ( a.high != 0xC03E ) || aSig ) {
float_raise(float_flag_invalid, status);
if ( ! aSign || ( ( aExp == 0x7FFF ) && aSig ) ) {
return LIT64( 0x7FFFFFFFFFFFFFFF );
return INT64_MAX;
}
}
return (int64_t) LIT64( 0x8000000000000000 );
return INT64_MIN;
}
else if ( aExp < 0x3FFF ) {
if (aExp | aSig) {
@ -6602,7 +6600,7 @@ int32_t float128_to_int32_round_to_zero(float128 a, float_status *status)
if ( ( z < 0 ) ^ aSign ) {
invalid:
float_raise(float_flag_invalid, status);
return aSign ? (int32_t) 0x80000000 : 0x7FFFFFFF;
return aSign ? INT32_MIN : INT32_MAX;
}
if ( ( aSig0<<shiftCount ) != savedASig ) {
status->float_exception_flags |= float_flag_inexact;
@ -6641,9 +6639,9 @@ int64_t float128_to_int64(float128 a, float_status *status)
&& ( aSig1 || ( aSig0 != LIT64( 0x0001000000000000 ) ) )
)
) {
return LIT64( 0x7FFFFFFFFFFFFFFF );
return INT64_MAX;
}
return (int64_t) LIT64( 0x8000000000000000 );
return INT64_MIN;
}
shortShift128Left( aSig0, aSig1, - shiftCount, &aSig0, &aSig1 );
}
@ -6689,10 +6687,10 @@ int64_t float128_to_int64_round_to_zero(float128 a, float_status *status)
else {
float_raise(float_flag_invalid, status);
if ( ! aSign || ( ( aExp == 0x7FFF ) && ( aSig0 | aSig1 ) ) ) {
return LIT64( 0x7FFFFFFFFFFFFFFF );
return INT64_MAX;
}
}
return (int64_t) LIT64( 0x8000000000000000 );
return INT64_MIN;
}
z = ( aSig0<<shiftCount ) | ( aSig1>>( ( - shiftCount ) & 63 ) );
if ( (uint64_t) ( aSig1<<shiftCount ) ) {
@ -6743,19 +6741,19 @@ uint64_t float128_to_uint64(float128 a, float_status *status)
if (aSign && (aExp > 0x3FFE)) {
float_raise(float_flag_invalid, status);
if (float128_is_any_nan(a)) {
return LIT64(0xFFFFFFFFFFFFFFFF);
return UINT64_MAX;
} else {
return 0;
}
}
if (aExp) {
aSig0 |= LIT64(0x0001000000000000);
aSig0 |= UINT64_C(0x0001000000000000);
}
shiftCount = 0x402F - aExp;
if (shiftCount <= 0) {
if (0x403E < aExp) {
float_raise(float_flag_invalid, status);
return LIT64(0xFFFFFFFFFFFFFFFF);
return UINT64_MAX;
}
shortShift128Left(aSig0, aSig1, -shiftCount, &aSig0, &aSig1);
} else {