sdcc-3.9.0 fork implementing GNU assembler syntax

This fork aims to provide better support for stm8-binutils

1 files changed, 80 insertions, 0 deletions

diff --git a/device/lib/free.c b/device/lib/free.c
new file mode 100644
index 0000000..bf1fdcd
--- /dev/null
+++ b/device/lib/free.c
@@ -0,0 +1,80 @@
+/*-------------------------------------------------------------------------
+   free.c - deallocate memory.
+
+   Copyright (C) 2015, Philipp Klaus Krause, pkk@spth.de
+
+   This library is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published by the
+   Free Software Foundation; either version 2, or (at your option) any
+   later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License 
+   along with this library; see the file COPYING. If not, write to the
+   Free Software Foundation, 51 Franklin Street, Fifth Floor, Boston,
+   MA 02110-1301, USA.
+
+   As a special exception, if you link this library with other files,
+   some of which are compiled with SDCC, to produce an executable,
+   this library does not by itself cause the resulting executable to
+   be covered by the GNU General Public License. This exception does
+   not however invalidate any other reasons why the executable file
+   might be covered by the GNU General Public License.
+-------------------------------------------------------------------------*/
+
+#include <stdlib.h>
+#include <stddef.h>
+
+#if defined(__SDCC_mcs51) || defined(__SDCC_ds390) || defined(__SDCC_ds400)
+#define HEAPSPACE __xdata
+#elif defined(__SDCC_pdk13) || defined(__SDCC_pdk14) || defined(__SDCC_pdk15)
+#define HEAPSPACE __near
+#else
+#define HEAPSPACE
+#endif
+
+typedef struct header HEAPSPACE header_t;
+
+struct header
+{
+	header_t *next;
+	header_t *next_free;
+};
+
+extern header_t *HEAPSPACE __sdcc_heap_free;
+
+void free(void *ptr)
+{
+	header_t *h, *next_free, *prev_free;
+	header_t *HEAPSPACE *f;
+
+	if(!ptr)
+		return;
+
+	prev_free = 0;
+	for(h = __sdcc_heap_free, f = &__sdcc_heap_free; h && h < ptr; prev_free = h, f = &(h->next_free), h = h->next_free); // Find adjacent blocks in free list
+	next_free = h;
+
+	h = (void HEAPSPACE *)((char HEAPSPACE *)(ptr) - offsetof(struct header, next_free));
+
+	// Insert into free list.
+	h->next_free = next_free;
+	*f = h;
+
+	if(next_free == h->next) // Merge with next block
+	{
+		h->next_free = h->next->next_free;
+		h->next = h->next->next;
+	}
+
+	if (prev_free && prev_free->next == h) // Merge with previous block
+	{
+		prev_free->next = h->next;
+		prev_free->next_free = h->next_free;
+	}
+}
+