I am trying to write binary literals in a cleaner format.
I understand that the following can be done for integer literals:
int x = 1234_5678_9999;
I assumed this would work for binary literals, so I tried:
uint32_t branch_bitmask = 0b0000_1111_0000_0000_0000_0000_0000_0000;
Which gives me an "invalid suffix" error for everything past the first underscore.
Is there an alternative to underscores that would allow me to write the binary literal in a cleaner way than just:
uint32_t branch_bitmask = 0b00001111000000000000000000000000;
If you always have the same number of bits (32 in your example) you could #define a macro a bit like this:
#define BITS32(b1,b2,b3,b4,b5,b6,b7,b8) ( \
((b1) << 28) + \
((b2) << 24) + \
((b3) << 20) + \
((b4) << 16) + \
((b5) << 12) + \
((b6) << 8) + \
((b7) << 4) + \
(b8))
and then call it like this:
uint32_t branch_bitmask = BITS32(0b0000,0b1111,0b0000,0b0000,0b0000,0b0000,0b0000,0b0000);
or you can go further and use ## in the macro to prepend the 0b.
But the simple answer for me has always been to use hexadecimal, as one hex digit is 4 bits.
uint32_t branch_bitmask = 0x0F000000;