DBtiles.c: DBFreePaintPlane() remove the TiFree() deferred assumption #380
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This asks the compiler the check the assumptions that are currently documented in the comments in this file.
The comment indicates the expectation that TiFree() is deferred-by-one, which would be true if freeMalloc() was used but since the custom mmap() allocator technically this is not true. The TiFree() allocator is single-threaded and separate from libc so the assumption is still kind of true but for different reasons (single-threaded). But since it doesn't really cost anything (other than a few lines of code a human needs to read) the compiler would be expected to perform a load (which it was going to do anyway) into a caller-saves register over the function call. Most of the other function state is invalidated anyway due to the heavy linked-list navigation and low number of local variables, I would not think there is much register allocation pressure. TODO this code can be tested by confirming zero allocations are active and by invalidating (poison) all fields inside TiFree().
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The intention now is to add valgrind specific hints via Not sure if you want that (valgrind hints) as an additional commit with ifdef around ? There is already Merge Status: merge on hold (pending valgrind style testing, review status in 2 months) |
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