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"nice" floating-point literals seem to work

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pommicket 2022-01-12 12:54:06 -05:00
parent 0d0455ce92
commit f17720731d
3 changed files with 14 additions and 13 deletions
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24
05/tokenize.b
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@ -122,6 +122,7 @@ function tokenize
local data
local significand
local exponent
local new_exponent
local pow10
local integer
local fraction
@ -305,24 +306,25 @@ function tokenize
putc(10)
if integer == 0 goto float_no_integer
; now deal with the integer part
n = leftmost_1bit(integer)
n += 1
new_exponent = leftmost_1bit(integer)
new_exponent -= 58
n = new_exponent - exponent
significand = right_shift(significand, n)
exponent += n
exponent = new_exponent
significand += right_shift(integer, exponent)
putn(significand)
putc(32)
putn_signed(exponent)
putc(10)
if *1in != 'e goto float_no_exponent
:float_no_exponent
if significand == 0 goto float_zero
normalize_float(&significand, &exponent)
; reduce to 52-bit significant
significand >= 6
exponent += 6
exponent += 51 ; 1001010111... => 1.001010111...
putn(significand)
putc(32)
putn_signed(exponent)
putc(10)
; reduce to 53-bit significant (top bit is removed to get 52)
significand >= 5
exponent += 5
exponent += 52 ; 1001010111... => 1.001010111...
n = leftmost_1bit(significand)
b = 1 < n
significand &= ~b