view tests/mini/ptrarith.d @ 1275:bedf0bfb8fdb

Implement first D-specific optimization pass: -simplify-drtcalls. It uses the machinery of the standard -simplify-libcalls pass, but optimizes calls to the D runtime instead of calls to C libraries. At the moment, these optimizations are implemented by this pass: - Avoid the runtime call for `arr.length = newlen` if it can determine that the new length isn't longer than the old one. - Ditto for `cast(T[]) arr` if it will clearly always succeed. (e.g. if the length of the original array is zero, or if the old element size is a multiple of the new element size)
author Frits van Bommel <fvbommel wxs.nl>
date Tue, 28 Apr 2009 21:58:06 +0200
parents 1bb99290e03a
children
line wrap: on
line source

extern(C) int printf(char*, ...);

void main()
{
    printf("Pointer arithmetic test\n");
    int* p;
    printf("0x%x\n", p);
    assert(p++ is null);
    assert(cast(size_t)p == 4);
    printf("0x%x\n", p);
    p--;
    assert(p is null);
    printf("0x%x\n", p);
    int d = 4;
    p+=d;
    printf("0x%x\n", p);
    assert(cast(size_t)p == 16);
    d = 2;
    p+=d;
    printf("0x%x\n", p);
    assert(cast(size_t)p == 0x18);
    d = 6;
    p-=d;
    printf("0x%x\n", p);
    assert(p is null);
    printf("  SUCCESS\n");
}

void fill_byte_array(ubyte* a, size_t n, ubyte v)
{
    auto p = a;
    auto end = a+n;
    while (p !is end)
        *p++ = v;
}