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Heap changes for surveyor

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git-svn-id: http://picoc.googlecode.com/svn/trunk@123 21eae674-98b7-11dd-bd71-f92a316d2d60
This commit is contained in:
zik.saleeba 2009-02-28 19:26:48 +00:00
parent 9f8770047f
commit 127f03eb4e
1 changed files with 21 additions and 14 deletions
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35
heap.c
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@ -4,11 +4,18 @@
#define FREELIST_BUCKETS 8 /* freelists for 4, 8, 12 ... 32 byte allocs */
#define SPLIT_MEM_THRESHOLD 16 /* don't split memory which is close in size */
#ifdef SURVEYOR_HOST
#define HEAP_SIZE C_HEAPSIZE
static unsigned char *HeapMemory = (unsigned char *)C_HEAPSTART;
static void *HeapBottom = C_HEAPSTART + HEAP_SIZE; /* the bottom of the (downward-growing) heap */
#else
static unsigned char HeapMemory[HEAP_SIZE]; /* all memory - stack and heap */
static void *StackFrame = &HeapMemory; /* the current stack frame */
static void *StackTop = &HeapMemory; /* the top of the stack */
static void *HeapBottom = &HeapMemory[HEAP_SIZE]; /* the bottom of the (downward-growing) heap */
#endif
static void *StackFrame = &HeapMemory[0]; /* the current stack frame */
static void *StackTop = &HeapMemory[0]; /* the top of the stack */
static struct AllocNode *FreeListBucket[FREELIST_BUCKETS]; /* we keep a pool of freelist buckets to reduce fragmentation */
static struct AllocNode *FreeListBig; /* free memory which doesn't fit in a bucket */
@ -17,8 +24,8 @@ void HeapInit()
{
int Count;
StackFrame = &HeapMemory;
StackTop = &HeapMemory;
StackFrame = &HeapMemory[0];
StackTop = &HeapMemory[0];
*(void **)StackFrame = NULL;
HeapBottom = &HeapMemory[HEAP_SIZE];
FreeListBig = NULL;
@ -44,7 +51,7 @@ void *HeapAllocStack(int Size)
int HeapPopStack(void *Addr, int Size)
{
int ToLose = MEM_ALIGN(Size);
if (ToLose > (StackTop - (void *)&HeapMemory))
if (ToLose > (StackTop - (void *)&HeapMemory[0]))
return FALSE;
StackTop -= ToLose;
@ -97,9 +104,9 @@ void *HeapAlloc(int Size)
printf("allocating %d(%d) from bucket", Size, AllocSize);
#endif
NewMem = FreeListBucket[Bucket];
assert((unsigned long)NewMem >= (unsigned long)&HeapMemory && (unsigned char *)NewMem - &HeapMemory[0] < HEAP_SIZE);
assert((unsigned long)NewMem >= (unsigned long)&HeapMemory[0] && (unsigned char *)NewMem - &HeapMemory[0] < HEAP_SIZE);
FreeListBucket[Bucket] = *(struct AllocNode **)NewMem;
assert(FreeListBucket[Bucket] == NULL || ((unsigned long)FreeListBucket[Bucket] >= (unsigned long)&HeapMemory && (unsigned char *)FreeListBucket[Bucket] - &HeapMemory[0] < HEAP_SIZE));
assert(FreeListBucket[Bucket] == NULL || ((unsigned long)FreeListBucket[Bucket] >= (unsigned long)&HeapMemory[0] && (unsigned char *)FreeListBucket[Bucket] - &HeapMemory[0] < HEAP_SIZE));
NewMem->Size = AllocSize;
}
else if (FreeListBig != NULL)
@ -109,7 +116,7 @@ void *HeapAlloc(int Size)
if (*FreeNode != NULL)
{
assert((unsigned long)*FreeNode >= (unsigned long)&HeapMemory && (unsigned char *)*FreeNode - &HeapMemory[0] < HEAP_SIZE);
assert((unsigned long)*FreeNode >= (unsigned long)&HeapMemory[0] && (unsigned char *)*FreeNode - &HeapMemory[0] < HEAP_SIZE);
assert((*FreeNode)->Size < HEAP_SIZE && (*FreeNode)->Size > 0);
if ((*FreeNode)->Size < Size + SPLIT_MEM_THRESHOLD)
{ /* close in size - reduce fragmentation by not splitting */
@ -117,7 +124,7 @@ void *HeapAlloc(int Size)
printf("allocating %d(%d) from freelist, no split (%d)", Size, AllocSize, (*FreeNode)->Size);
#endif
NewMem = *FreeNode;
assert((unsigned long)NewMem >= (unsigned long)&HeapMemory && (unsigned char *)NewMem - &HeapMemory[0] < HEAP_SIZE);
assert((unsigned long)NewMem >= (unsigned long)&HeapMemory[0] && (unsigned char *)NewMem - &HeapMemory[0] < HEAP_SIZE);
*FreeNode = NewMem->NextFree;
}
else
@ -126,7 +133,7 @@ void *HeapAlloc(int Size)
printf("allocating %d(%d) from freelist, split chunk (%d)", Size, AllocSize, (*FreeNode)->Size);
#endif
NewMem = *FreeNode + (*FreeNode)->Size - AllocSize;
assert((unsigned long)NewMem >= (unsigned long)&HeapMemory && (unsigned char *)NewMem - &HeapMemory[0] < HEAP_SIZE);
assert((unsigned long)NewMem >= (unsigned long)&HeapMemory[0] && (unsigned char *)NewMem - &HeapMemory[0] < HEAP_SIZE);
(*FreeNode)->Size -= AllocSize;
NewMem->Size = AllocSize;
}
@ -159,7 +166,7 @@ void HeapFree(void *Mem)
struct AllocNode *MemNode = (struct AllocNode *)(Mem-sizeof(int));
int Bucket = MemNode->Size >> 2;
assert((unsigned long)Mem >= (unsigned long)&HeapMemory && (unsigned char *)Mem - &HeapMemory[0] < HEAP_SIZE);
assert((unsigned long)Mem >= (unsigned long)&HeapMemory[0] && (unsigned char *)Mem - &HeapMemory[0] < HEAP_SIZE);
assert(MemNode->Size < HEAP_SIZE && MemNode->Size > 0);
if (Mem == NULL)
return;
@ -176,7 +183,7 @@ void HeapFree(void *Mem)
#ifdef DEBUG_HEAP
printf("freeing %d to bucket\n", MemNode->Size);
#endif
assert(FreeListBucket[Bucket] == NULL || ((unsigned long)FreeListBucket[Bucket] >= (unsigned long)&HeapMemory && (unsigned char *)FreeListBucket[Bucket] - &HeapMemory[0] < HEAP_SIZE));
assert(FreeListBucket[Bucket] == NULL || ((unsigned long)FreeListBucket[Bucket] >= (unsigned long)&HeapMemory[0] && (unsigned char *)FreeListBucket[Bucket] - &HeapMemory[0] < HEAP_SIZE));
*(struct AllocNode **)MemNode = FreeListBucket[Bucket];
FreeListBucket[Bucket] = (struct AllocNode *)MemNode;
}
@ -185,7 +192,7 @@ void HeapFree(void *Mem)
#ifdef DEBUG_HEAP
printf("freeing %lx:%d to freelist\n", (unsigned long)Mem, MemNode->Size);
#endif
assert(FreeListBig == NULL || ((unsigned long)FreeListBig >= (unsigned long)&HeapMemory && (unsigned char *)FreeListBig - &HeapMemory[0] < HEAP_SIZE));
assert(FreeListBig == NULL || ((unsigned long)FreeListBig >= (unsigned long)&HeapMemory[0] && (unsigned char *)FreeListBig - &HeapMemory[0] < HEAP_SIZE));
MemNode->NextFree = FreeListBig;
FreeListBig = MemNode;
}