IntLog2

Description

Compute floor(log2(value)).

This public macro supports both forms:

• IntLog2(value) - returns the result, no error channel.
• IntLog2(value, error) - writes the error flag through error.

Parameters

Usage example (from documentation)

  u64 hi = IntLog2(&value);

Success

Returns the zero-based index of the highest set bit as a u64. The integer is not modified.

Failure

Returns 0 when value is zero. With the two-argument form *error is set to true; with the one-argument form the caller cannot distinguish zero-input from log2(1).

Usage example (Cross-references)

    
    bool test_int_log2(void) {
        WriteFmt("Testing IntLog2\n");
    
        DefaultAllocator alloc = DefaultAllocatorInit();

        bool error = true;
    
        bool result = IntLog2(&value, &error) == 10;
        result      = result && !error;

    
    bool test_int_log2_zero(void) {
        WriteFmt("Testing IntLog2 zero handling\n");
    
        DefaultAllocator alloc = DefaultAllocatorInit();

        bool error = false;
    
        bool result = IntLog2(&value, &error) == 0;
        result      = result && error;