py/parsenum: Use pow function to apply exponent to decimal number.

dpgeorge · dpgeorge · commit 259967238423 · 2016-03-29T22:12:07.000+01:00
Pow is already a dependency when compiling with floats, so may as well
use it here to reduce code size and speed up the conversion for most
cases.
diff --git a/py/parsenum.c b/py/parsenum.c
@@ -263,12 +263,7 @@ mp_obj_t mp_parse_num_decimal(const char *str, size_t len, bool allow_imag, bool
         }
 
         // apply the exponent
-        for (; exp_val > 0; exp_val--) {
-            dec_val *= 10;
-        }
-        for (; exp_val < 0; exp_val++) {
-            dec_val *= 0.1;
-        }
+        dec_val *= MICROPY_FLOAT_C_FUN(pow)(10, exp_val);
     }
 
     // negate value if needed

Original file line number	Diff line number	Diff line change
`@@ -263,12 +263,7 @@ mp_obj_t mp_parse_num_decimal(const char *str, size_t len, bool allow_imag, bool`
`263`	`263`	`}`
`264`	`264`
`265`	`265`	`// apply the exponent`
`266`		`- for (; exp_val > 0; exp_val--) {`
`267`		`- dec_val *= 10;`
`268`		`- }`
`269`		`- for (; exp_val < 0; exp_val++) {`
`270`		`- dec_val *= 0.1;`
`271`		`- }`
	`266`	`+ dec_val *= MICROPY_FLOAT_C_FUN(pow)(10, exp_val);`
`272`	`267`	`}`
`273`	`268`
`274`	`269`	`// negate value if needed`