riscv
/
qemu
mirror of https://gitea.goldendeliverer.com/riscv/qemu.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity
Browse Source

fpu: add mechanism to check for invalid long double formats 

All operations that take a floatx80 as an operand need to have their
inputs checked for malformed encodings. In all of these cases, use the
function floatx80_invalid_encoding to perform the check. If an invalid
operand is found, raise an invalid operation exception, and then return
either NaN (for fp-typed results) or the integer indefinite value (the
minimum representable signed integer value, for int-typed results).

For the non-quiet comparison operations, this touches adjacent code in
order to pass style checks.

Signed-off-by: Andrew Dutcher <andrew@andrewdutcher.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1471392895-17324-1-git-send-email-andrew@andrewdutcher.com
[PMM: changed "1 << 63" to "1ULL << 63" to fix compile errors]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
pull/44/head
Andrew Dutcher 10 years ago
committed by Peter Maydell
parent
9e8204b1de
commit
d1eb8f2acb
2 changed files with 115 additions and 16 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 116
      fpu/softfloat.c
  2. 15
      include/fpu/softfloat.h

116
fpu/softfloat.c
View File

@ -4814,6 +4814,10 @@ int32_t floatx80_to_int32(floatx80 a, float_status *status)
int32_t aExp, shiftCount;
uint64_t aSig;
if (floatx80_invalid_encoding(a)) {
float_raise(float_flag_invalid, status);
return 1 << 31;
}
aSig = extractFloatx80Frac( a );
aExp = extractFloatx80Exp( a );
aSign = extractFloatx80Sign( a );
@ -4842,6 +4846,10 @@ int32_t floatx80_to_int32_round_to_zero(floatx80 a, float_status *status)
uint64_t aSig, savedASig;
int32_t z;
if (floatx80_invalid_encoding(a)) {
float_raise(float_flag_invalid, status);
return 1 << 31;
}
aSig = extractFloatx80Frac( a );
aExp = extractFloatx80Exp( a );
aSign = extractFloatx80Sign( a );
@ -4888,6 +4896,10 @@ int64_t floatx80_to_int64(floatx80 a, float_status *status)
int32_t aExp, shiftCount;
uint64_t aSig, aSigExtra;
if (floatx80_invalid_encoding(a)) {
float_raise(float_flag_invalid, status);
return 1ULL << 63;
}
aSig = extractFloatx80Frac( a );
aExp = extractFloatx80Exp( a );
aSign = extractFloatx80Sign( a );
@ -4929,6 +4941,10 @@ int64_t floatx80_to_int64_round_to_zero(floatx80 a, float_status *status)
uint64_t aSig;
int64_t z;
if (floatx80_invalid_encoding(a)) {
float_raise(float_flag_invalid, status);
return 1ULL << 63;
}
aSig = extractFloatx80Frac( a );
aExp = extractFloatx80Exp( a );
aSign = extractFloatx80Sign( a );
@ -4971,6 +4987,10 @@ float32 floatx80_to_float32(floatx80 a, float_status *status)
int32_t aExp;
uint64_t aSig;
if (floatx80_invalid_encoding(a)) {
float_raise(float_flag_invalid, status);
return float32_default_nan(status);
}
aSig = extractFloatx80Frac( a );
aExp = extractFloatx80Exp( a );
aSign = extractFloatx80Sign( a );
@ -4999,6 +5019,10 @@ float64 floatx80_to_float64(floatx80 a, float_status *status)
int32_t aExp;
uint64_t aSig, zSig;
if (floatx80_invalid_encoding(a)) {
float_raise(float_flag_invalid, status);
return float64_default_nan(status);
}
aSig = extractFloatx80Frac( a );
aExp = extractFloatx80Exp( a );
aSign = extractFloatx80Sign( a );
@ -5027,6 +5051,10 @@ float128 floatx80_to_float128(floatx80 a, float_status *status)
int aExp;
uint64_t aSig, zSig0, zSig1;
if (floatx80_invalid_encoding(a)) {
float_raise(float_flag_invalid, status);
return float128_default_nan(status);
}
aSig = extractFloatx80Frac( a );
aExp = extractFloatx80Exp( a );
aSign = extractFloatx80Sign( a );
@ -5052,6 +5080,10 @@ floatx80 floatx80_round_to_int(floatx80 a, float_status *status)
uint64_t lastBitMask, roundBitsMask;
floatx80 z;
if (floatx80_invalid_encoding(a)) {
float_raise(float_flag_invalid, status);
return floatx80_default_nan(status);
}
aExp = extractFloatx80Exp( a );
if ( 0x403E <= aExp ) {
if ( ( aExp == 0x7FFF ) && (uint64_t) ( extractFloatx80Frac( a )<<1 ) ) {
@ -5279,6 +5311,10 @@ floatx80 floatx80_add(floatx80 a, floatx80 b, float_status *status)
{
flag aSign, bSign;
if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
float_raise(float_flag_invalid, status);
return floatx80_default_nan(status);
}
aSign = extractFloatx80Sign( a );
bSign = extractFloatx80Sign( b );
if ( aSign == bSign ) {
@ -5300,6 +5336,10 @@ floatx80 floatx80_sub(floatx80 a, floatx80 b, float_status *status)
{
flag aSign, bSign;
if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
float_raise(float_flag_invalid, status);
return floatx80_default_nan(status);
}
aSign = extractFloatx80Sign( a );
bSign = extractFloatx80Sign( b );
if ( aSign == bSign ) {
@ -5323,6 +5363,10 @@ floatx80 floatx80_mul(floatx80 a, floatx80 b, float_status *status)
int32_t aExp, bExp, zExp;
uint64_t aSig, bSig, zSig0, zSig1;
if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
float_raise(float_flag_invalid, status);
return floatx80_default_nan(status);
}
aSig = extractFloatx80Frac( a );
aExp = extractFloatx80Exp( a );
aSign = extractFloatx80Sign( a );
@ -5380,6 +5424,10 @@ floatx80 floatx80_div(floatx80 a, floatx80 b, float_status *status)
uint64_t aSig, bSig, zSig0, zSig1;
uint64_t rem0, rem1, rem2, term0, term1, term2;
if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
float_raise(float_flag_invalid, status);
return floatx80_default_nan(status);
}
aSig = extractFloatx80Frac( a );
aExp = extractFloatx80Exp( a );
aSign = extractFloatx80Sign( a );
@ -5461,6 +5509,10 @@ floatx80 floatx80_rem(floatx80 a, floatx80 b, float_status *status)
uint64_t aSig0, aSig1, bSig;
uint64_t q, term0, term1, alternateASig0, alternateASig1;
if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
float_raise(float_flag_invalid, status);
return floatx80_default_nan(status);
}
aSig0 = extractFloatx80Frac( a );
aExp = extractFloatx80Exp( a );
aSign = extractFloatx80Sign( a );
@ -5556,6 +5608,10 @@ floatx80 floatx80_sqrt(floatx80 a, float_status *status)
uint64_t aSig0, aSig1, zSig0, zSig1, doubleZSig0;
uint64_t rem0, rem1, rem2, rem3, term0, term1, term2, term3;
if (floatx80_invalid_encoding(a)) {
float_raise(float_flag_invalid, status);
return floatx80_default_nan(status);
}
aSig0 = extractFloatx80Frac( a );
aExp = extractFloatx80Exp( a );
aSign = extractFloatx80Sign( a );
@ -5620,10 +5676,11 @@ floatx80 floatx80_sqrt(floatx80 a, float_status *status)
int floatx80_eq(floatx80 a, floatx80 b, float_status *status)
{
if ( ( ( extractFloatx80Exp( a ) == 0x7FFF )
&& (uint64_t) ( extractFloatx80Frac( a )<<1 ) )
|| ( ( extractFloatx80Exp( b ) == 0x7FFF )
&& (uint64_t) ( extractFloatx80Frac( b )<<1 ) )
if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)
|| (extractFloatx80Exp(a) == 0x7FFF
&& (uint64_t) (extractFloatx80Frac(a) << 1))
|| (extractFloatx80Exp(b) == 0x7FFF
&& (uint64_t) (extractFloatx80Frac(b) << 1))
) {
float_raise(float_flag_invalid, status);
return 0;
@ -5649,10 +5706,11 @@ int floatx80_le(floatx80 a, floatx80 b, float_status *status)
{
flag aSign, bSign;
if ( ( ( extractFloatx80Exp( a ) == 0x7FFF )
&& (uint64_t) ( extractFloatx80Frac( a )<<1 ) )
|| ( ( extractFloatx80Exp( b ) == 0x7FFF )
&& (uint64_t) ( extractFloatx80Frac( b )<<1 ) )
if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)
|| (extractFloatx80Exp(a) == 0x7FFF
&& (uint64_t) (extractFloatx80Frac(a) << 1))
|| (extractFloatx80Exp(b) == 0x7FFF
&& (uint64_t) (extractFloatx80Frac(b) << 1))
) {
float_raise(float_flag_invalid, status);
return 0;
@ -5682,10 +5740,11 @@ int floatx80_lt(floatx80 a, floatx80 b, float_status *status)
{
flag aSign, bSign;
if ( ( ( extractFloatx80Exp( a ) == 0x7FFF )
&& (uint64_t) ( extractFloatx80Frac( a )<<1 ) )
|| ( ( extractFloatx80Exp( b ) == 0x7FFF )
&& (uint64_t) ( extractFloatx80Frac( b )<<1 ) )
if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)
|| (extractFloatx80Exp(a) == 0x7FFF
&& (uint64_t) (extractFloatx80Frac(a) << 1))
|| (extractFloatx80Exp(b) == 0x7FFF
&& (uint64_t) (extractFloatx80Frac(b) << 1))
) {
float_raise(float_flag_invalid, status);
return 0;
@ -5712,10 +5771,11 @@ int floatx80_lt(floatx80 a, floatx80 b, float_status *status)
*----------------------------------------------------------------------------*/
int floatx80_unordered(floatx80 a, floatx80 b, float_status *status)
{
if ( ( ( extractFloatx80Exp( a ) == 0x7FFF )
&& (uint64_t) ( extractFloatx80Frac( a )<<1 ) )
|| ( ( extractFloatx80Exp( b ) == 0x7FFF )
&& (uint64_t) ( extractFloatx80Frac( b )<<1 ) )
if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)
|| (extractFloatx80Exp(a) == 0x7FFF
&& (uint64_t) (extractFloatx80Frac(a) << 1))
|| (extractFloatx80Exp(b) == 0x7FFF
&& (uint64_t) (extractFloatx80Frac(b) << 1))
) {
float_raise(float_flag_invalid, status);
return 1;
@ -5733,6 +5793,10 @@ int floatx80_unordered(floatx80 a, floatx80 b, float_status *status)
int floatx80_eq_quiet(floatx80 a, floatx80 b, float_status *status)
{
if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
float_raise(float_flag_invalid, status);
return 0;
}
if ( ( ( extractFloatx80Exp( a ) == 0x7FFF )
&& (uint64_t) ( extractFloatx80Frac( a )<<1 ) )
|| ( ( extractFloatx80Exp( b ) == 0x7FFF )
@ -5764,6 +5828,10 @@ int floatx80_le_quiet(floatx80 a, floatx80 b, float_status *status)
{
flag aSign, bSign;
if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
float_raise(float_flag_invalid, status);
return 0;
}
if ( ( ( extractFloatx80Exp( a ) == 0x7FFF )
&& (uint64_t) ( extractFloatx80Frac( a )<<1 ) )
|| ( ( extractFloatx80Exp( b ) == 0x7FFF )
@ -5800,6 +5868,10 @@ int floatx80_lt_quiet(floatx80 a, floatx80 b, float_status *status)
{
flag aSign, bSign;
if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
float_raise(float_flag_invalid, status);
return 0;
}
if ( ( ( extractFloatx80Exp( a ) == 0x7FFF )
&& (uint64_t) ( extractFloatx80Frac( a )<<1 ) )
|| ( ( extractFloatx80Exp( b ) == 0x7FFF )
@ -5833,6 +5905,10 @@ int floatx80_lt_quiet(floatx80 a, floatx80 b, float_status *status)
*----------------------------------------------------------------------------*/
int floatx80_unordered_quiet(floatx80 a, floatx80 b, float_status *status)
{
if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
float_raise(float_flag_invalid, status);
return 1;
}
if ( ( ( extractFloatx80Exp( a ) == 0x7FFF )
&& (uint64_t) ( extractFloatx80Frac( a )<<1 ) )
|| ( ( extractFloatx80Exp( b ) == 0x7FFF )
@ -7374,6 +7450,10 @@ static inline int floatx80_compare_internal(floatx80 a, floatx80 b,
{
flag aSign, bSign;
if (floatx80_invalid_encoding(a) || floatx80_invalid_encoding(b)) {
float_raise(float_flag_invalid, status);
return float_relation_unordered;
}
if (( ( extractFloatx80Exp( a ) == 0x7fff ) &&
( extractFloatx80Frac( a )<<1 ) ) ||
( ( extractFloatx80Exp( b ) == 0x7fff ) &&
@ -7645,6 +7725,10 @@ floatx80 floatx80_scalbn(floatx80 a, int n, float_status *status)
int32_t aExp;
uint64_t aSig;
if (floatx80_invalid_encoding(a)) {
float_raise(float_flag_invalid, status);
return floatx80_default_nan(status);
}
aSig = extractFloatx80Frac( a );
aExp = extractFloatx80Exp( a );
aSign = extractFloatx80Sign( a );

15
include/fpu/softfloat.h
View File

@ -658,6 +658,21 @@ static inline int floatx80_is_any_nan(floatx80 a)
return ((a.high & 0x7fff) == 0x7fff) && (a.low<<1);
}
/*----------------------------------------------------------------------------
| Return whether the given value is an invalid floatx80 encoding.
| Invalid floatx80 encodings arise when the integer bit is not set, but
| the exponent is not zero. The only times the integer bit is permitted to
| be zero is in subnormal numbers and the value zero.
| This includes what the Intel software developer's manual calls pseudo-NaNs,
| pseudo-infinities and un-normal numbers. It does not include
| pseudo-denormals, which must still be correctly handled as inputs even
| if they are never generated as outputs.
*----------------------------------------------------------------------------*/
static inline bool floatx80_invalid_encoding(floatx80 a)
{
return (a.low & (1ULL << 63)) == 0 && (a.high & 0x7FFF) != 0;
}
#define floatx80_zero make_floatx80(0x0000, 0x0000000000000000LL)
#define floatx80_one make_floatx80(0x3fff, 0x8000000000000000LL)
#define floatx80_ln2 make_floatx80(0x3ffe, 0xb17217f7d1cf79acLL)

Write Preview
Loading…
Cancel
Save