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fix: avoid premature overflow in math/base/special/coshf and sinhf #16267

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fix: avoid premature overflow in math/base/special/coshf and sinhf #16267

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10 changes: 8 additions & 2 deletions lib/node_modules/@stdlib/math/base/special/coshf/lib/main.js
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Original file line number Diff line number Diff line change
Expand Up @@ -45,6 +45,7 @@ var MAXLOGF = require( '@stdlib/constants/float32/max-ln' );
// VARIABLES //

var ZERO = f32( 0.0 );
var HALF = f32( 0.5 );
var ONE = f32( 1.0 );
var TWO = f32( 2.0 );

Expand Down Expand Up @@ -95,10 +96,15 @@ function coshf( x ) {
if ( x < ZERO ) {
x = -x;
}
// Handle infinities & overflows:
if ( isInfinitef( x ) || x > MAXLOGF ) {
// Handle infinities:
if ( isInfinitef( x ) ) {
return PINF;
}
// Avoid premature overflow by evaluating `exp(x/2) * exp(x/2) / 2`:
if ( x >= MAXLOGF ) {
z = f32( exp( f32( HALF * x ) ) );
return f32( f32( HALF * z ) * z );
}
z = f32( exp( f32( x ) ) );
z = f32( z + ( ONE/z ) );
return f32( z / TWO );
Expand Down
7 changes: 6 additions & 1 deletion lib/node_modules/@stdlib/math/base/special/coshf/src/main.c
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Expand Up @@ -77,9 +77,14 @@ float stdlib_base_coshf( const float x ) {
} else {
z = x;
}
if ( stdlib_base_is_infinitef( z ) || z > MAXLOGF ) {
if ( stdlib_base_is_infinitef( z ) ) {
return STDLIB_CONSTANT_FLOAT32_PINF;
}
// Avoid premature overflow by evaluating `exp(x/2) * exp(x/2) / 2`:
if ( z >= MAXLOGF ) {
z = expf( 0.5f * z );
return ( 0.5f * z ) * z;
}
z = expf( z );
z = z + ( 1.0f/z );
return ( z / 2.0f );
Expand Down
29 changes: 25 additions & 4 deletions lib/node_modules/@stdlib/math/base/special/coshf/test/test.js
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Expand Up @@ -130,28 +130,49 @@ tape( 'the function returns `+infinity` if provided a `-infinity`', function tes
t.end();
});

tape( 'the function returns `+infinity` if provided a value greater than `MAXLOGF`', function test( t ) {
tape( 'the function returns `+infinity` if provided a value greater than `MAXLOGF + 1`', function test( t ) {
var v;
var i;
var y;

for ( i = 0; i < 500; i++ ) {
v = f32( ( randu()*1e3 ) + MAXLOGF );
v = f32( ( randu()*1e3 ) + MAXLOGF + 1.0 );
y = coshf( v );
t.strictEqual( y, PINF, 'returns expected value' );
}
t.end();
});

tape( 'the function returns `+infinity` if provided a value less than `-MAXLOGF`', function test( t ) {
tape( 'the function returns `+infinity` if provided a value less than `-MAXLOGF - 1`', function test( t ) {
var y;
var v;
var i;

for ( i = 0; i < 500; i++ ) {
v = f32( ( -randu()*1e3 ) - MAXLOGF );
v = f32( ( -randu()*1e3 ) - MAXLOGF - 1.0 );
y = coshf( v );
t.strictEqual( y, PINF, 'returns expected value' );
}
t.end();
});

tape( 'the function does not overflow for values whose hyperbolic cosine is representable', function test( t ) {
var expected;
var x;
var v;
var i;

x = [ 89.0, 89.2, 89.4 ];
expected = [
2.2448063889081578e+38,
2.741804322770982e+38,
3.3488627241070614e+38
];
for ( i = 0; i < x.length; i++ ) {
v = coshf( f32( x[ i ] ) );
t.strictEqual( isAlmostSameValue( v, expected[ i ], 2 ), true, 'returns expected value' );
v = coshf( f32( -x[ i ] ) );
t.strictEqual( isAlmostSameValue( v, expected[ i ], 2 ), true, 'returns expected value' );
}
t.end();
});
29 changes: 25 additions & 4 deletions lib/node_modules/@stdlib/math/base/special/coshf/test/test.native.js
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Original file line number Diff line number Diff line change
Expand Up @@ -139,28 +139,49 @@ tape( 'the function returns `+infinity` if provided a `-infinity`', opts, functi
t.end();
});

tape( 'the function returns `+infinity` if provided a value greater than `MAXLOGF`', opts, function test( t ) {
tape( 'the function returns `+infinity` if provided a value greater than `MAXLOGF + 1`', opts, function test( t ) {
var v;
var i;
var y;

for ( i = 0; i < 500; i++ ) {
v = f32( ( randu()*1e3 ) + MAXLOGF );
v = f32( ( randu()*1e3 ) + MAXLOGF + 1.0 );
y = coshf( v );
t.strictEqual( y, PINF, 'returns expected value' );
}
t.end();
});

tape( 'the function returns `+infinity` if provided a value less than `-MAXLOGF`', opts, function test( t ) {
tape( 'the function returns `+infinity` if provided a value less than `-MAXLOGF - 1`', opts, function test( t ) {
var y;
var v;
var i;

for ( i = 0; i < 500; i++ ) {
v = f32( ( -randu()*1e3 ) - MAXLOGF );
v = f32( ( -randu()*1e3 ) - MAXLOGF - 1.0 );
y = coshf( v );
t.strictEqual( y, PINF, 'returns expected value' );
}
t.end();
});

tape( 'the function does not overflow for values whose hyperbolic cosine is representable', opts, function test( t ) {
var expected;
var x;
var v;
var i;

x = [ 89.0, 89.2, 89.4 ];
expected = [
2.2448063889081578e+38,
2.741804322770982e+38,
3.3488627241070614e+38
];
for ( i = 0; i < x.length; i++ ) {
v = coshf( f32( x[ i ] ) );
t.strictEqual( isAlmostSameValue( v, expected[ i ], 2 ), true, 'returns expected value' );
v = coshf( f32( -x[ i ] ) );
t.strictEqual( isAlmostSameValue( v, expected[ i ], 2 ), true, 'returns expected value' );
}
t.end();
});
14 changes: 7 additions & 7 deletions lib/node_modules/@stdlib/math/base/special/sinhf/lib/main.js
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Original file line number Diff line number Diff line change
Expand Up @@ -38,8 +38,6 @@ var isnanf = require( '@stdlib/math/base/assert/is-nanf' );
var isInfinitef = require( '@stdlib/math/base/assert/is-infinitef' );
var expf = require( '@stdlib/math/base/special/expf' );
var f32 = require( '@stdlib/number/float64/base/to-float32' );
var PINF = require( '@stdlib/constants/float32/pinf' );
var NINF = require( '@stdlib/constants/float32/ninf' );
var MAXLOGF = require( '@stdlib/constants/float32/max-ln' );
var polyvalP = require( './polyval_p.js' );

Expand Down Expand Up @@ -110,12 +108,14 @@ function sinhf( x ) {
} else {
a = -x;
}
// Handle overflow:
if ( a > MAXLOGF ) {
if ( x > ZERO ) {
return PINF;
// Avoid premature overflow by evaluating `exp(|x|/2) * exp(|x|/2) / 2`:
if ( a >= MAXLOGF ) {
z = expf( f32( ONE_HALF * a ) );
z = f32( f32( ONE_HALF * z ) * z );
if ( x < ZERO ) {
z = -z;
}
return NINF;
return z;
}
if ( a > ONE ) {
z = expf( a );
Expand Down
6 changes: 0 additions & 6 deletions lib/node_modules/@stdlib/math/base/special/sinhf/manifest.json
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Expand Up @@ -40,8 +40,6 @@
"@stdlib/math/base/assert/is-nanf",
"@stdlib/math/base/assert/is-infinitef",
"@stdlib/math/base/special/expf",
"@stdlib/constants/float32/pinf",
"@stdlib/constants/float32/ninf",
"@stdlib/constants/float32/max-ln"
]
},
Expand All @@ -59,8 +57,6 @@
"@stdlib/math/base/assert/is-nanf",
"@stdlib/math/base/assert/is-infinitef",
"@stdlib/math/base/special/expf",
"@stdlib/constants/float32/pinf",
"@stdlib/constants/float32/ninf",
"@stdlib/constants/float32/max-ln"
]
},
Expand All @@ -78,8 +74,6 @@
"@stdlib/math/base/assert/is-nanf",
"@stdlib/math/base/assert/is-infinitef",
"@stdlib/math/base/special/expf",
"@stdlib/constants/float32/pinf",
"@stdlib/constants/float32/ninf",
"@stdlib/constants/float32/max-ln"
]
}
Expand Down
14 changes: 7 additions & 7 deletions lib/node_modules/@stdlib/math/base/special/sinhf/src/main.c
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Expand Up @@ -33,8 +33,6 @@
#include "stdlib/math/base/special/sinhf.h"
#include "stdlib/math/base/assert/is_nanf.h"
#include "stdlib/math/base/assert/is_infinitef.h"
#include "stdlib/constants/float32/pinf.h"
#include "stdlib/constants/float32/ninf.h"
#include "stdlib/constants/float32/max_ln.h"
#include "stdlib/math/base/special/expf.h"

Expand Down Expand Up @@ -106,12 +104,14 @@ float stdlib_base_sinhf( const float x ) {
} else {
a = -x;
}
// Handle overflow:
if ( a > STDLIB_CONSTANT_FLOAT32_MAX_LN ) {
if ( x > 0.0f ) {
return STDLIB_CONSTANT_FLOAT32_PINF;
// Avoid premature overflow by evaluating `exp(|x|/2) * exp(|x|/2) / 2`:
if ( a >= STDLIB_CONSTANT_FLOAT32_MAX_LN ) {
z = stdlib_base_expf( 0.5f * a );
z = ( 0.5f * z ) * z;
if ( x < 0.0f ) {
z = -z;
}
return STDLIB_CONSTANT_FLOAT32_NINF;
return z;
}
if ( a > 1.0f ) {
z = stdlib_base_expf( a );
Expand Down
29 changes: 25 additions & 4 deletions lib/node_modules/@stdlib/math/base/special/sinhf/test/test.js
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Expand Up @@ -130,14 +130,14 @@ tape( 'the function returns `-0` if provided `-0`', function test( t ) {
t.end();
});

tape( 'the function returns `+infinity` if provided a value greater than `MAXLOGF`', function test( t ) {
var v = sinhf( f32( 89.0 ) );
tape( 'the function returns `+infinity` if provided a value greater than `MAXLOGF + ln(2)`', function test( t ) {
var v = sinhf( f32( 90.0 ) );
t.strictEqual( v, PINF, 'returns expected value' );
t.end();
});

tape( 'the function returns `-infinity` if provided a value less than `-MAXLOGF`', function test( t ) {
var v = sinhf( f32( -89.0 ) );
tape( 'the function returns `-infinity` if provided a value less than `-MAXLOGF - ln(2)`', function test( t ) {
var v = sinhf( f32( -90.0 ) );
t.strictEqual( v, NINF, 'returns expected value' );
t.end();
});
Expand Down Expand Up @@ -197,3 +197,24 @@ tape( 'the function handles subnormal inputs', function test( t ) {

t.end();
});

tape( 'the function does not overflow for values whose hyperbolic sine is representable', function test( t ) {
var expected;
var x;
var v;
var i;

x = [ 89.0, 89.2, 89.4 ];
expected = [
2.2448063889081578e+38,
2.741804322770982e+38,
3.3488627241070614e+38
];
for ( i = 0; i < x.length; i++ ) {
v = sinhf( f32( x[ i ] ) );
t.strictEqual( isAlmostSameValuef( v, expected[ i ], 2 ), true, 'returns expected value' );
v = sinhf( f32( -x[ i ] ) );
t.strictEqual( isAlmostSameValuef( v, -expected[ i ], 2 ), true, 'returns expected value' );
}
t.end();
});
29 changes: 25 additions & 4 deletions lib/node_modules/@stdlib/math/base/special/sinhf/test/test.native.js
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Original file line number Diff line number Diff line change
Expand Up @@ -139,14 +139,14 @@ tape( 'the function returns `-0` if provided `-0`', opts, function test( t ) {
t.end();
});

tape( 'the function returns `+infinity` if provided a value greater than `MAXLOGF`', opts, function test( t ) {
var v = sinhf( f32( 89.0 ) );
tape( 'the function returns `+infinity` if provided a value greater than `MAXLOGF + ln(2)`', opts, function test( t ) {
var v = sinhf( f32( 90.0 ) );
t.strictEqual( v, PINF, 'returns expected value' );
t.end();
});

tape( 'the function returns `-infinity` if provided a value less than `-MAXLOGF`', opts, function test( t ) {
var v = sinhf( f32( -89.0 ) );
tape( 'the function returns `-infinity` if provided a value less than `-MAXLOGF - ln(2)`', opts, function test( t ) {
var v = sinhf( f32( -90.0 ) );
t.strictEqual( v, NINF, 'returns expected value' );
t.end();
});
Expand Down Expand Up @@ -206,3 +206,24 @@ tape( 'the function handles subnormal inputs', opts, function test( t ) {

t.end();
});

tape( 'the function does not overflow for values whose hyperbolic sine is representable', opts, function test( t ) {
var expected;
var x;
var v;
var i;

x = [ 89.0, 89.2, 89.4 ];
expected = [
2.2448063889081578e+38,
2.741804322770982e+38,
3.3488627241070614e+38
];
for ( i = 0; i < x.length; i++ ) {
v = sinhf( f32( x[ i ] ) );
t.strictEqual( isAlmostSameValuef( v, expected[ i ], 2 ), true, 'returns expected value' );
v = sinhf( f32( -x[ i ] ) );
t.strictEqual( isAlmostSameValuef( v, -expected[ i ], 2 ), true, 'returns expected value' );
}
t.end();
});
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