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Fix detection of integer value on ascii conversion
author William Astle <lost@l-w.ca>
date Sun, 22 Oct 2023 21:03:24 -0600
parents 5fa8c479dbf7
children 6837d10b67fb
comparison
equal deleted inserted replaced
94:5fa8c479dbf7 95:25b44f1ac2aa
237 std val0+val.int+2 237 std val0+val.int+2
238 rts 238 rts
239 ; Normalization is not required here though rounding might be. Rounding will be handled during floating point return. 239 ; Normalization is not required here though rounding might be. Rounding will be handled during floating point return.
240 ; By ensuring there were no leading zeroes converted, the result is already pre-normalized without losing precision due 240 ; By ensuring there were no leading zeroes converted, the result is already pre-normalized without losing precision due
241 ; to an aribtrary number of leading zeroes. 241 ; to an aribtrary number of leading zeroes.
242 val_parsenum11a cmpb fpaextra ; is the exponent less than the number of digits? 242 val_parsenum11a cmpb #9 ; is the exponent greater than possible for a 32 bit integer?
243 blt val_parsenum13 ; brif so - return floating point (signed comparison!) 243 bgt val_parsenum13
244 cmpb #10 ; is exponent in the range for a binary integer? 244 lda fpaextra ; fetch the number of digits
245 bgt val_parsenum13 ; brif not - return floating point 245 deca ; account for the decimal point offset
246 cmpa fpa0+fpa.exp ; do we have more digits than the exponent (fractional)?
247 bgt val_parsenum13 ; brif we have more digits than exponent
246 ; Compare with 2147483648, the maximum *negative* value; note that this is a floating point comparison because we 248 ; Compare with 2147483648, the maximum *negative* value; note that this is a floating point comparison because we
247 ; already normalized everything above and it handles exponents properly 249 ; already normalized everything above and it handles exponents properly
248 lda fpa0+fpa.exp ; compare exponents (unbiased), exponent adjusted for above code 250 lda fpa0+fpa.exp ; compare exponents (unbiased)
249 cmpa #10 251 cmpa #9
250 bne val_parsenum12 252 bne val_parsenum12
251 ldx fpa0+fpa.sig ; compare top of significand 253 ldx fpa0+fpa.sig ; compare top of significand
252 cmpx #0x2147 254 cmpx #0x2147
253 bne val_parsenum12 255 bne val_parsenum12
254 ldx fpa0+fpa.sig+2 ; compare middle of significand 256 ldx fpa0+fpa.sig+2 ; compare middle of significand
267 sta fpa0+fpa.exp 269 sta fpa0+fpa.exp
268 ldy #val0+val.value ; normalize/round and return the result 270 ldy #val0+val.value ; normalize/round and return the result
269 jmp fps_normalize 271 jmp fps_normalize
270 val_parsenum14 lda #valtype_int ; set value type to integer 272 val_parsenum14 lda #valtype_int ; set value type to integer
271 sta val0+val.type 273 sta val0+val.type
272 ldb #10 ; exponent needed for decimal point to the right of significand 274 ldb #9 ; exponent needed for decimal point to the right of significand
273 subb fpa0+fpa.exp ; number of digit shifts needed to denormalize 275 subb fpa0+fpa.exp ; number of digit shifts needed to denormalize
274 beq val_parsenum16 ; brif already denormalized 276 beq val_parsenum16 ; brif already denormalized
275 lslb ; do 4 shifts per digit 277 lslb ; do 4 shifts per digit
276 lslb 278 lslb
277 val_parsenum15 lsr fpa0+fpa.sig ; shift a digit right 279 val_parsenum15 lsr fpa0+fpa.sig ; shift a digit right