Homebrew written for a PSP-2000+ under custom firmware can use the top
32MB of RAM directly without setting MEMSIZE, which leaves the user
partition at its normal size. NJEMU's slim builds do this (#8925).
Previously we didn't map that memory at all for PBPs; MEMSIZE=1 isn't a
workaround either, since it grows the partition and the heap and stacks
land where the program writes.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Serializing the kernel memory block lists (userMemory, kernelMemory,
volatileMemory) wrote a full Section header per block and re-zeroed
each block's tag padding with strlen+memset on every save. Games keep
on the order of a thousand blocks alive, so the per-block overhead is
both measurable save time and wasted payload bytes.
Zero-pad tags once at write time instead (Block constructor and
SetAllocated), so the v2 form can store blocks raw: start, size, taken,
tag - no per-block section machinery, no per-save tag scrubbing.
Uninitialized padding still never reaches the stream, since every path
that writes a tag now clears it first.
v1 states still load through the old per-block-Section form, which is
kept unchanged.
