view dmd/mem.c @ 1317:4099548c80e0

Allocate objects on the stack if they (a) don't have a destructor, and (b) don't override the delete operator (on top of the regular conditions for stack allocation that also apply to arrays, structs, etc.). The "no destructor" clause is not strictly necessary, but calling them at the right time would be tricky to say the least; it would involve, among other things, "manually" inserting a try-finally block around anything that might throw exceptions not caught in the current function. Note: objects with custom new operators are automatically ignored because they don't use the regular allocation runtime call, so there's no need to pay special attention to them.
author Frits van Bommel <fvbommel wxs.nl>
date Sat, 09 May 2009 00:50:15 +0200
parents b30fe7e1dbb9
children
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/* Copyright (c) 2000 Digital Mars	*/
/* All Rights Reserved 			*/

#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cassert>

#include "rmem.h"

#if USE_BOEHM_GC
    // I needed to perfix the dir after upgrading to gc 7.0
    #include "gc/gc.h"
#endif

/* This implementation of the storage allocator uses the standard C allocation package.
 */

Mem mem;

#if USE_BOEHM_GC

static bool gc_was_init = false;

void Mem::init()
{
    GC_init();
    gc_was_init = true;
}

char *Mem::strdup(const char *s)
{
    char *p;

    if (s)
    {
	p = GC_strdup(s);
	if (p)
	    return p;
	error();
    }
    return NULL;
}

void *Mem::malloc(size_t size)
{   void *p;

    if (!size)
	p = NULL;
    else
    {
	p = GC_malloc(size);
	if (!p)
	    error();
    }
    return p;
}

void *Mem::calloc(size_t size, size_t n)
{   void *p;

    if (!size || !n)
	p = NULL;
    else
    {
	p = GC_malloc(size * n);
	if (!p)
	    error();
        memset(p, 0, size * n);
    }
    return p;
}

void *Mem::realloc(void *p, size_t size)
{
    if (!size)
    {	if (p)
	{   GC_free(p);
	    p = NULL;
	}
    }
    else if (!p)
    {
	p = GC_malloc(size);
	if (!p)
	    error();
    }
    else
    {
	p = GC_realloc(p, size);
	if (!p)
	    error();
    }
    return p;
}

void Mem::free(void *p)
{
    if (p)
	GC_free(p);
}

void *Mem::mallocdup(void *o, size_t size)
{   void *p;

    if (!size)
	p = NULL;
    else
    {
	p = GC_malloc(size);
	if (!p)
	    error();
	else
	    memcpy(p,o,size);
    }
    return p;
}

void Mem::error()
{
    printf("Error: out of memory\n");
    exit(EXIT_FAILURE);
}

void Mem::fullcollect()
{
    GC_gcollect();
}

void Mem::mark(void *pointer)
{
    (void) pointer;		// necessary for VC /W4
}

/* =================================================== */

void * operator new(size_t m_size)
{
    // without this we segfault with gc 7.0
    if (!gc_was_init) {
        mem.init();
    }
    void *p = GC_malloc(m_size);
    if (p)
	return p;
    printf("Error: out of memory\n");
    exit(EXIT_FAILURE);
    return p;
}

void operator delete(void *p)
{
    GC_free(p);
}

#elif !USE_BOEHM_GC

void Mem::init()
{
}

char *Mem::strdup(const char *s)
{
    char *p;

    if (s)
    {
    p = ::strdup(s);
    if (p)
        return p;
    error();
    }
    return NULL;
}

void *Mem::malloc(size_t size)
{   void *p;

    if (!size)
    p = NULL;
    else
    {
    p = ::malloc(size);
    if (!p)
        error();
    }
    return p;
}

void *Mem::calloc(size_t size, size_t n)
{   void *p;

    if (!size || !n)
    p = NULL;
    else
    {
    p = ::malloc(size * n);
    if (!p)
        error();
        memset(p, 0, size * n);
    }
    return p;
}

void *Mem::realloc(void *p, size_t size)
{
    if (!size)
    {   if (p)
    {   ::free(p);
        p = NULL;
    }
    }
    else if (!p)
    {
    p = ::malloc(size);
    if (!p)
        error();
    }
    else
    {
    p = ::realloc(p, size);
    if (!p)
        error();
    }
    return p;
}

void Mem::free(void *p)
{
    if (p)
        ::free(p);
}

void *Mem::mallocdup(void *o, size_t size)
{   void *p;

    if (!size)
        p = NULL;
    else
    {
        p = ::malloc(size);
        if (!p)
            error();
        else
            memcpy(p,o,size);
    }
    return p;
}

void Mem::error()
{
    printf("Error: out of memory\n");
    exit(EXIT_FAILURE);
}

void Mem::fullcollect()
{
}

void Mem::mark(void *pointer)
{
}

#endif // USE_BOEHM_GC