Lerking/micropython
1
0
Fork 0
mirror of https://github.com/micropython/micropython.git synced 2025-07-21 04:51:12 +02:00
Code Issues Actions 25 Packages Projects Releases Wiki Activity

py/parsenum: Reduce code size in check for inf/nan.

Browse Source 
By avoiding two different checks of the string length, code size is reduced
without changing behavior: Some invalid float/complex strings like "ix"
will get handled just like "xx" in the main number literal parsing code
instead.

The optimizer alone couldn't remove the reundant comparisons because it
couldn't make a transformation that let an invalid string like "ix" pass
into the generic number parsing code.

Signed-off-by: Jeff Epler <jepler@gmail.com>
This commit is contained in:
Jeff Epler
2025-05-30 07:54:08 +02:00
committed by Damien George
parent 745bec9ce3
commit 5eb9755259
1 changed files with 4 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files

8
py/parsenum.c
View File

@@ -252,9 +252,9 @@ parse_start:
const char *str_val_start = str;
// determine what the string is
if (str < top && (str[0] | 0x20) == 'i') {
if (str + 2 < top && (str[0] | 0x20) == 'i') {
// string starts with 'i', should be 'inf' or 'infinity' (case insensitive)
if (str + 2 < top && (str[1] | 0x20) == 'n' && (str[2] | 0x20) == 'f') {
if ((str[1] | 0x20) == 'n' && (str[2] | 0x20) == 'f') {
// inf
str += 3;
dec_val = (mp_float_t)INFINITY;
@@ -263,9 +263,9 @@ parse_start:
str += 5;
}
}
} else if (str < top && (str[0] | 0x20) == 'n') {
} else if (str + 2 < top && (str[0] | 0x20) == 'n') {
// string starts with 'n', should be 'nan' (case insensitive)
if (str + 2 < top && (str[1] | 0x20) == 'a' && (str[2] | 0x20) == 'n') {
if ((str[1] | 0x20) == 'a' && (str[2] | 0x20) == 'n') {
// NaN
str += 3;
dec_val = MICROPY_FLOAT_C_FUN(nan)("");