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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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1
05/main.b
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@ -88,7 +88,6 @@ function main
local tokens local tokens
fill_in_powers_of_10() fill_in_powers_of_10()
print_powers_of_10()
dat_banned_objmacros = 255 dat_banned_objmacros = 255
dat_banned_fmacros = 255 dat_banned_fmacros = 255

2
05/main.c
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@ -2,4 +2,4 @@
char * = "How are you"" d""o""i""ng today?\n"; char * = "How are you"" d""o""i""ng today?\n";
hi hi
_TEST _ING _1 _TEST _ING _1
4.2 1.00001

24
05/tokenize.b
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@ -122,6 +122,7 @@ function tokenize
local data local data
local significand local significand
local exponent local exponent
local new_exponent
local pow10 local pow10
local integer local integer
local fraction local fraction
@ -305,24 +306,25 @@ function tokenize
putc(10) putc(10)
if integer == 0 goto float_no_integer if integer == 0 goto float_no_integer
; now deal with the integer part ; now deal with the integer part
n = leftmost_1bit(integer) new_exponent = leftmost_1bit(integer)
n += 1 new_exponent -= 58
n = new_exponent - exponent
significand = right_shift(significand, n) significand = right_shift(significand, n)
exponent += n exponent = new_exponent
significand += right_shift(integer, exponent) significand += right_shift(integer, exponent)
putn(significand)
putc(32)
putn_signed(exponent)
putc(10)
if *1in != 'e goto float_no_exponent if *1in != 'e goto float_no_exponent
:float_no_exponent :float_no_exponent
if significand == 0 goto float_zero if significand == 0 goto float_zero
normalize_float(&significand, &exponent) normalize_float(&significand, &exponent)
; reduce to 52-bit significant putn(significand)
significand >= 6 putc(32)
exponent += 6 putn_signed(exponent)
exponent += 51 ; 1001010111... => 1.001010111... 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) n = leftmost_1bit(significand)
b = 1 < n b = 1 < n
significand &= ~b significand &= ~b