Description Todd Mullanix 2010-12-02 20:34:53 EST

We currently have Memory_getMaxDefaultTypeAlign and Memory_getMaxDefaultTypeAlignMeta, but it would be nice to have a constant and type that we can use in the definition of buffer sizes.  

For example, if a heap states that it has requires alignment at least as big as Memory_getMaxDefaultTypeAlign, what's the best way for the user to insure this?

One approach is the following:

typedef struct FooStruct {
   // fields whose total size is not a multiple of Memory_getMaxDefaultTypeAlign
} FooStruct;

typedef struct Aligned_FooStruct {
   UInt64 filler[( sizeof(FooStruct) + sizeof(UInt64) – 1 ) / sizeof(UInt64)]; 
} Aligned_FooStruct;

#define NUMBLOCKS 31
Aligned_FooStruct buffer[NUMBLOCKS];

heapParams.numBlocks = NUMBLOCKS;
heapParams.blockSize = sizeof(FooStruct);
heapParams.size = sizeof(buffer);
heapParams.buf = buffer;
heap create...

Note I had to guess what the largest type size was UInt64. It would have been nicer to have a constant or even a new type (e.g. LargestType).