math.integers, fix bignum/f for results in ]0x1.0p-1022,0x0.4p-1022]

db4
Jon Harper 2015-07-26 17:53:42 +02:00 committed by John Benediktsson
parent f3c85e0598
commit cc6d90a096
2 changed files with 8 additions and 1 deletions

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@ -272,3 +272,10 @@ IN: math.integers.tests
{ -1/0. } [ 2048 2^ -1 /f ] unit-test { -1/0. } [ 2048 2^ -1 /f ] unit-test
{ -1/0. } [ 2048 2^ neg 1 /f ] unit-test { -1/0. } [ 2048 2^ neg 1 /f ] unit-test
{ 1/0. } [ 2048 2^ neg -1 /f ] unit-test { 1/0. } [ 2048 2^ neg -1 /f ] unit-test
! bignum/f had a bug for results in ]0x1.0p-1022,0x0.4p-1022]
! these are the first subnormals...
{ 0x0.cp-1022 } [ 12 1026 2^ /f ] unit-test
{ 0x0.8p-1022 } [ 8 1026 2^ /f ] unit-test
{ 0x0.6p-1022 } [ 6 1026 2^ /f ] unit-test
{ 0x0.4p-1022 } [ 4 1026 2^ /f ] unit-test

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@ -142,7 +142,7 @@ M: bignum (log2) bignum-log2 ; inline
: scale-float ( mantissa scale -- float' ) : scale-float ( mantissa scale -- float' )
{ {
{ [ dup 1024 > ] [ 2drop 1/0. ] } { [ dup 1024 > ] [ 2drop 1/0. ] }
{ [ dup -1023 < ] [ 1021 + shift bits>double ] } { [ dup -1021 < ] [ 1021 + shift bits>double ] }
[ [ 52 2^ 1 - bitand ] dip 1022 + 52 shift bitor bits>double ] [ [ 52 2^ 1 - bitand ] dip 1022 + 52 shift bitor bits>double ]
} cond ; inline } cond ; inline