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GC API: Difference between revisions
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layout/alignment/OOM notes
(whoops, layout without location is kinda silly!) |
(layout/alignment/OOM notes) |
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(Where the layout information isn't a speed win, the implementation can of course just discard it. A hacky implementation can just delegate <code>gc_alloc_with_layout</code> and <code>gc_alloc_array_with_layout</code> to <code>gc_alloc_conservative</code>. Sloppy, but fine by me.) | (Where the layout information isn't a speed win, the implementation can of course just discard it. A hacky implementation can just delegate <code>gc_alloc_with_layout</code> and <code>gc_alloc_array_with_layout</code> to <code>gc_alloc_conservative</code>. Sloppy, but fine by me.) | ||
XXXbsmedberg: I think this incorrect. At least if layout information specifies that a word is not a GC pointer, we should reliably not trace that word. | |||
All these functions return a pointer to a newly allocated region of memory that is subject to GC (that is, the GC may collect it when it becomes unreachable), or <code>NULL</code> on failure. | All these functions return a pointer to a newly allocated region of memory that is subject to GC (that is, the GC may collect it when it becomes unreachable), or <code>NULL</code> on failure. XXXbsmedberg: the OOM API probably requires either that allocation functions never fail, or that there is a variant of these functions that never fail. | ||
All allocations are <code>malloc</code>-aligned (that is, alignment is such that the pointer can be cast to any reasonable C/C++ type and used). | All allocations are <code>malloc</code>-aligned (that is, alignment is such that the pointer can be cast to any reasonable C/C++ type and used). They must be at least 8-byte aligned, so that three bits of tag are available. | ||
typedef enum GCAllocFlags { | typedef enum GCAllocFlags { | ||