Twenty four places moved Q into A or B by pushing it and popping it back.
That is four bus cycles and two bytes to do what MVQA does in one of each,
and several of them are inside loops - Life, the calculator, int8. Nineteen
more loaded zero with INIA 0d0 where RSTA says the same thing in one byte.
Both are equivalent at the CPU rather than by assertion: RSTA and INIA both
leave Status alone, and PSHQ followed by POPA nets to A = Q with the Stack
Pointer where it started. The one difference is that the pair leaves a copy
of Q in memory just below the Stack Pointer and MVQA does not, which
nothing here reads.
Five recorded outputs moved and every one of them says the change worked:
- 16x16Life fits five more generations into the same cycle budget, the
first 457 lines identical, because the loop got cheaper.
- Life.sbx is 1409 bytes rather than 1411, in three tests that list it.
- Edit.sbx is 1995 rather than 1996.
That last one broke a check I added this morning, and the hole is worth
recording: the CosmOS README's claim about Edit's size did not have the
word "Edit" on the same line as the number, because the subject was in the
sentence before, so the check that measures quoted sizes skipped it
silently. The sentence now names what it is talking about, which makes it
both checkable and clearer, and the check fails on a wrong number there.
Comments on either half of a replaced pair are carried onto the
instruction that replaces them, so nothing anybody wrote was lost.
Five .asm files sat at the top of Programs/ beside six directories, with
nothing to say which a new file should join - and hello.asm, which is the
native assembler's first target and named in sixteen places, looked like a
stray.
Programs/
Examples/ what you read to learn: hello, printHello, inputTest,
replCalculator, and Fibonacci, primeSieve and gameOfLife
as sets of their own
Libraries/ included by name, no entry point of their own
Loader/ loader.asm, and the loadable program it reads
CosmOS/ the system, its applications and its assembler
testPrograms/ what 'make test' drives
Loader/ is the one worth explaining. loader.asm is not a demonstration: it
reads a program off a disk, puts the two pieces where the header asks, and
jumps to the entry. CosmOS grew out of it and does the same thing as one of
its commands. It is kept because backward compatibility with the simplest
version of the system is a standing goal, and it was sitting loose next to
the demos as though it were one.
Programs/loadable/ was a directory holding one file called hello.asm - a
third thing of that name, and the name said nothing about why it was there.
It is Loader/loadable.asm now, beside the loader that reads it.
Every reference moved with them: the makefile's program list, twelve
manifest lines, makedisks.sh, native.sh, and four paths across the README
and both manuals. Verified by deleting both build directories and running
the whole suite from nothing.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW