view lphobos/typeinfo2/ti_Ag.d @ 1168:ab186e535e72

A different fix to #218 and DMD2682 that does not lead to constant folding regressions. Fixes run/const_15, run/c/const_16_B. The price is removing the lvalueness of struct literals. If it turns out too much code depends on this behavior or we don't want to break with DMD, we could keep struct literals as lvalues and instead convert struct literals used as expression initializers into struct initializers.
author Christian Kamm <kamm incasoftware de>
date Sun, 29 Mar 2009 11:43:45 +0200
parents 362825278842
children
line wrap: on
line source

module typeinfo2.ti_Ag;

private int string_cmp(char[] s1, char[] s2)
{
    auto len = s1.length;
    if (s2.length < len)
        len = s2.length;
    int result = memcmp(s1.ptr, s2.ptr, len);
    if (result == 0)
        result = cast(int)(cast(ptrdiff_t)s1.length - cast(ptrdiff_t)s2.length);
    return result;
}

extern(C) int memcmp(void*,void*,size_t);

// byte[]

class TypeInfo_Ag : TypeInfo
{
    char[] toString() { return "byte[]"; }

    hash_t getHash(void *p)
    {	byte[] s = *cast(byte[]*)p;
	size_t len = s.length;
	byte *str = s.ptr;
	hash_t hash = 0;

	while (1)
	{
	    switch (len)
	    {
		case 0:
		    return hash;

		case 1:
		    hash *= 9;
		    hash += *cast(ubyte *)str;
		    return hash;

		case 2:
		    hash *= 9;
		    hash += *cast(ushort *)str;
		    return hash;

		case 3:
		    hash *= 9;
		    hash += (*cast(ushort *)str << 8) +
			    (cast(ubyte *)str)[2];
		    return hash;

		default:
		    hash *= 9;
		    hash += *cast(uint *)str;
		    str += 4;
		    len -= 4;
		    break;
	    }
	}

	return hash;
    }

    int equals(void *p1, void *p2)
    {
	byte[] s1 = *cast(byte[]*)p1;
	byte[] s2 = *cast(byte[]*)p2;

	return s1.length == s2.length &&
	       memcmp(cast(byte *)s1, cast(byte *)s2, s1.length) == 0;
    }

    int compare(void *p1, void *p2)
    {
	byte[] s1 = *cast(byte[]*)p1;
	byte[] s2 = *cast(byte[]*)p2;
	size_t len = s1.length;

	if (s2.length < len)
	    len = s2.length;
	for (size_t u = 0; u < len; u++)
	{
	    int result = s1[u] - s2[u];
	    if (result)
		return result;
	}
	return cast(int)s1.length - cast(int)s2.length;
    }

    size_t tsize()
    {
	return (byte[]).sizeof;
    }

    uint flags()
    {
	return 1;
    }

    TypeInfo next()
    {
	return typeid(byte);
    }
}


// ubyte[]

class TypeInfo_Ah : TypeInfo_Ag
{
    char[] toString() { return "ubyte[]"; }

    int compare(void *p1, void *p2)
    {
	char[] s1 = *cast(char[]*)p1;
	char[] s2 = *cast(char[]*)p2;

	return string_cmp(s1, s2);
    }

    TypeInfo next()
    {
	return typeid(ubyte);
    }
}

// void[]

class TypeInfo_Av : TypeInfo_Ah
{
    char[] toString() { return "void[]"; }

    TypeInfo next()
    {
	return typeid(void);
    }
}

// bool[]

class TypeInfo_Ab : TypeInfo_Ah
{
    char[] toString() { return "bool[]"; }

    TypeInfo next()
    {
	return typeid(bool);
    }
}

// char[]

class TypeInfo_Aa : TypeInfo_Ag
{
    char[] toString() { return "char[]"; }

    hash_t getHash(void *p)
    {	char[] s = *cast(char[]*)p;
	hash_t hash = 0;

version (all)
{
	foreach (char c; s)
	    hash = hash * 11 + c;
}
else
{
	size_t len = s.length;
	char *str = s;

	while (1)
	{
	    switch (len)
	    {
		case 0:
		    return hash;

		case 1:
		    hash *= 9;
		    hash += *cast(ubyte *)str;
		    return hash;

		case 2:
		    hash *= 9;
		    hash += *cast(ushort *)str;
		    return hash;

		case 3:
		    hash *= 9;
		    hash += (*cast(ushort *)str << 8) +
			    (cast(ubyte *)str)[2];
		    return hash;

		default:
		    hash *= 9;
		    hash += *cast(uint *)str;
		    str += 4;
		    len -= 4;
		    break;
	    }
	}
}
	return hash;
    }

    TypeInfo next()
    {
	return typeid(char);
    }
}