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<pre id='vimCodeElement'>
<span class="Comment">; Mu: An exploration on making the global structure of programs more accessible.</span>
<span class="Comment">;</span>
<span class="Comment">; "Is it a language, or an operating system, or a virtual machine? Mu."</span>
<span class="Comment">; (with apologies to Robert Pirsig: <a href="http://en.wikipedia.org/wiki/Mu_%28negative%29#In_popular_culture">http://en.wikipedia.org/wiki/Mu_%28negative%29#In_popular_culture</a>)</span>
<span class="Comment">;</span>
<span class="SalientComment">;; Motivation</span>
<span class="Comment">;</span>
<span class="Comment">; I want to live in a world where I can have an itch to tweak a program, clone</span>
<span class="Comment">; its open-source repository, orient myself on how it's organized, and make</span>
<span class="Comment">; the simple change I envisioned, all in an afternoon. This codebase tries to</span>
<span class="Comment">; make this possible for its readers. (More details: <a href="http://akkartik.name/about">http://akkartik.name/about</a>)</span>
<span class="Comment">;</span>
<span class="Comment">; What helps comprehend the global structure of programs? For starters, let's</span>
<span class="Comment">; enumerate what doesn't: idiomatic code, adherence to a style guide or naming</span>
<span class="Comment">; convention, consistent indentation, API documentation for each class, etc.</span>
<span class="Comment">; These conventional considerations improve matters in the small, but don't</span>
<span class="Comment">; help understand global organization. They help existing programmers manage</span>
<span class="Comment">; day-to-day operations, but they can't turn outsider programmers into</span>
<span class="Comment">; insiders. (Elaboration: <a href="http://akkartik.name/post/readable-bad">http://akkartik.name/post/readable-bad</a>)</span>
<span class="Comment">;</span>
<span class="Comment">; In my experience, two things have improved matters so far: version control</span>
<span class="Comment">; and automated tests. Version control lets me rewind back to earlier, simpler</span>
<span class="Comment">; times when the codebase was simpler, when its core skeleton was easier to</span>
<span class="Comment">; ascertain. Indeed, arguably what came first is by definition the skeleton of</span>
<span class="Comment">; a program, modulo major rewrites. Once you understand the skeleton, it</span>
<span class="Comment">; becomes tractable to 'play back' later major features one by one. (Previous</span>
<span class="Comment">; project that fleshed out this idea: <a href="http://akkartik.name/post/wart-layers">http://akkartik.name/post/wart-layers</a>)</span>
<span class="Comment">;</span>
<span class="Comment">; The second and biggest boost to comprehension comes from tests. Tests are</span>
<span class="Comment">; good for writers for well-understood reasons: they avoid regressions, and</span>
<span class="Comment">; they can influence code to be more decoupled and easier to change. In</span>
<span class="Comment">; addition, tests are also good for the outsider reader because they permit</span>
<span class="Comment">; active reading. If you can't build a program and run its tests it can't help</span>
<span class="Comment">; you understand it. It hangs limp at best, and might even be actively</span>
<span class="Comment">; misleading. If you can run its tests, however, it comes alive. You can step</span>
<span class="Comment">; through scenarios in a debugger. You can add logging and scan logs to make</span>
<span class="Comment">; sense of them. You can run what-if scenarios: "why is this line not written</span>
<span class="Comment">; like this?" Make a change, rerun tests: "Oh, that's why." (Elaboration:</span>
<span class="Comment">; <a href="http://akkartik.name/post/literate-programming">http://akkartik.name/post/literate-programming</a>)</span>
<span class="Comment">;</span>
<span class="Comment">; However, tests are only useful to the extent that they exist. Think back to</span>
<span class="Comment">; your most recent codebase. Do you feel comfortable releasing a new version</span>
<span class="Comment">; just because the tests pass? I'm not aware of any such project. There's just</span>
<span class="Comment">; too many situations envisaged by the authors that were never encoded in a</span>
<span class="Comment">; test. Even disciplined authors can't test for performance or race conditions</span>
<span class="Comment">; or fault tolerance. If a line is phrased just so because of some subtle</span>
<span class="Comment">; performance consideration, it's hard to communicate to newcomers.</span>
<span class="Comment">;</span>
<span class="Comment">; This isn't an arcane problem, and it isn't just a matter of altruism. As</span>
<span class="Comment">; more and more such implicit considerations proliferate, and as the original</span>
<span class="Comment">; authors are replaced by latecomers for day-to-day operations, knowledge is</span>
<span class="Comment">; actively forgotten and lost. The once-pristine codebase turns into legacy</span>
<span class="Comment">; code that is hard to modify without expensive and stress-inducing</span>
<span class="Comment">; regressions.</span>
<span class="Comment">;</span>
<span class="Comment">; How to write tests for performance, fault tolerance, race conditions, etc.?</span>
<span class="Comment">; How can we state and verify that a codepath doesn't ever perform memory</span>
<span class="Comment">; allocation, or write to disk? It requires better, more observable primitives</span>
<span class="Comment">; than we currently have. Modern operating systems have their roots in the</span>
<span class="Comment">; 70s. Their interfaces were not designed to be testable. They provide no way</span>
<span class="Comment">; to simulate a full disk, or a specific sequence of writes from different</span>
<span class="Comment">; threads. We need something better.</span>
<span class="Comment">;</span>
<span class="Comment">; This project tries to move, groping, towards that 'something better', a</span>
<span class="Comment">; platform that is both thoroughly tested and allows programs written for it</span>
<span class="Comment">; to be thoroughly tested. It tries to answer the question:</span>
<span class="Comment">;</span>
<span class="Comment">; If Denis Ritchie and Ken Thompson were to set out today to co-design unix</span>
<span class="Comment">; and C, knowing what we know about automated tests, what would they do</span>
<span class="Comment">; differently?</span>
<span class="Comment">;</span>
<span class="Comment">; To try to impose *some* constraints on this gigantic yak-shave, we'll try to</span>
<span class="Comment">; keep both language and OS as simple as possible, focused entirely on</span>
<span class="Comment">; permitting more kinds of tests, on first *collecting* all the information</span>
<span class="Comment">; about implicit considerations in some form so that readers and tools can</span>
<span class="Comment">; have at least some hope of making sense of it.</span>
<span class="Comment">;</span>
<span class="Comment">; The initial language will be just assembly. We'll try to make it convenient</span>
<span class="Comment">; to program in with some simple localized rewrite rules inspired by lisp</span>
<span class="Comment">; macros and literate programming. Programmers will have to do their own</span>
<span class="Comment">; memory management and register allocation, but we'll provide libraries to</span>
<span class="Comment">; help with them.</span>
<span class="Comment">;</span>
<span class="Comment">; The initial OS will provide just memory management and concurrency</span>
<span class="Comment">; primitives. No users or permissions (we don't live on mainframes anymore),</span>
<span class="Comment">; no kernel- vs user-mode, no virtual memory or process abstraction, all</span>
<span class="Comment">; threads sharing a single address space (use VMs for security and</span>
<span class="Comment">; sandboxing). The only use case we care about is getting a test harness to</span>
<span class="Comment">; run some code, feed it data through blocking channels, stop it and observe</span>
<span class="Comment">; its internals. The code under test is expected to cooperate in such testing,</span>
<span class="Comment">; by logging important events for the test harness to observe. (More info:</span>
<span class="Comment">; <a href="http://akkartik.name/post/tracing-tests">http://akkartik.name/post/tracing-tests</a>)</span>
<span class="Comment">;</span>
<span class="Comment">; The common thread here is elimination of abstractions, and it's not an</span>
<span class="Comment">; accident. Abstractions help insiders manage the evolution of a codebase, but</span>
<span class="Comment">; they actively hinder outsiders in understanding it from scratch. This</span>
<span class="Comment">; matters, because the funnel to turn outsiders into insiders is critical to</span>
<span class="Comment">; the long-term life of a codebase. Perhaps authors should raise their</span>
<span class="Comment">; estimation of the costs of abstraction, and go against their instincts for</span>
<span class="Comment">; introducing it. That's what I'll be trying to do: question every abstraction</span>
<span class="Comment">; before I introduce it. We'll see how it goes.</span>
<span class="Comment">; ---</span>
<span class="SalientComment">;; Getting started</span>
<span class="Comment">;</span>
<span class="Comment">; Mu is currently built atop Racket and Arc, but this is temporary and</span>
<span class="Comment">; contingent. We want to keep our options open, whether to port to a different</span>
<span class="Comment">; host language, and easy to rewrite to native code for any platform. So we'll</span>
<span class="Comment">; try to avoid 'cheating': relying on the host platform for advanced</span>
<span class="Comment">; functionality.</span>
<span class="Comment">;</span>
<span class="Comment">; Other than that, we'll say no more about the code, and focus in the rest of</span>
<span class="Comment">; this file on the scenarios the code cares about.</span>
<span class="Delimiter">(</span>selective-load <span class="Constant">"mu.arc"</span> section-level<span class="Delimiter">)</span>
<span class="CommentedCode">;? (quit)</span>
<span class="Delimiter">(</span>section <span class="Constant">20</span>
<span class="Comment">; Our language is assembly-like in that functions consist of series of</span>
<span class="Comment">; statements, and statements consist of an operation and its arguments (input</span>
<span class="Comment">; and output).</span>
<span class="Comment">;</span>
<span class="Comment">; oarg1, oarg2, ... <span class="Op"><-</span> op arg1, arg2, ...</span>
<span class="Comment">;</span>
<span class="Comment">; Args must be atomic, like an integer or a memory address, they can't be</span>
<span class="Comment">; expressions doing arithmetic or function calls. But we can have any number</span>
<span class="Comment">; of them.</span>
<span class="Comment">;</span>
<span class="Comment">; Since we're building on lisp, our code samples won't look quite like the</span>
<span class="Comment">; idealized syntax above. For now they will look like this:</span>
<span class="Comment">;</span>
<span class="Comment">; (function f [</span>
<span class="Comment">; (oarg1 oarg2 ... <span class="Op"><-</span> op arg1 arg2 ...)</span>
<span class="Comment">; ...</span>
<span class="Comment">; ...</span>
<span class="Comment">; ])</span>
<span class="Comment">;</span>
<span class="Comment">; Each arg/oarg can contain metadata separated by slashes and colons. In this</span>
<span class="Comment">; first example below, the only metadata is types: 'integer' for a memory</span>
<span class="Comment">; location containing an integer, and 'literal' for a value included directly</span>
<span class="Comment">; in code. (Assembly languages traditionally call them 'immediate' operands.)</span>
<span class="Comment">; In the future a simple tool will check that the types line up as expected in</span>
<span class="Comment">; each op. A different tool might add types where they aren't provided.</span>
<span class="Comment">; Instead of a monolithic compiler I want to build simple, lightweight tools</span>
<span class="Comment">; that can be combined in various ways, say for using different typecheckers</span>
<span class="Comment">; in different subsystems.</span>
<span class="Comment">;</span>
<span class="Comment">; In our tests we'll define such mu functions using a call to 'add-code', so</span>
<span class="Comment">; look for it when reading the code examples. Everything outside 'add-code' is</span>
<span class="Comment">; just test-harness details that can be skipped at first.</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="CommentedCode">;? (set dump-trace*)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"literal"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">23</span>:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="CommentedCode">;? (set dump-trace*)</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~is <span class="Global">memory*</span><span class="Constant">.1</span> <span class="Constant">23</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'copy' writes its lone 'arg' after the instruction name to its lone 'oarg' or output arg before the arrow. After this test, the value 23 is stored in memory address 1."</span><span class="Delimiter">))</span>
<span class="CommentedCode">;? (quit)</span>
<span class="Comment">; Our basic arithmetic ops can operate on memory locations or literals.</span>
<span class="Comment">; (Ignore hardware details like registers for now.)</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"add"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">1</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">3</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:integer <span class="Op"><-</span> add <span class="Constant">1</span>:integer <span class="Constant">2</span>:integer<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~iso <span class="Global">memory*</span> <span class="Delimiter">(</span>obj <span class="Constant">1</span> <span class="Constant">1</span> <span class="Constant">2</span> <span class="Constant">3</span> <span class="Constant">3</span> <span class="Constant">4</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'add' operates on two addresses"</span><span class="Delimiter">))</span>
<span class="CommentedCode">;? (quit)</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"add-literal"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> add <span class="MuConstant">2</span>:literal <span class="MuConstant">3</span>:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~is <span class="Global">memory*</span><span class="Constant">.1</span> <span class="Constant">5</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - ops can take 'literal' operands (but not return them)"</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"sub-literal"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> subtract <span class="MuConstant">1</span>:literal <span class="MuConstant">3</span>:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~is <span class="Global">memory*</span><span class="Constant">.1</span> <span class="Constant">-2</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'subtract'"</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"mul-literal"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> multiply <span class="MuConstant">2</span>:literal <span class="MuConstant">3</span>:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~is <span class="Global">memory*</span><span class="Constant">.1</span> <span class="Constant">6</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'multiply'"</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"div-literal"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> divide <span class="MuConstant">8</span>:literal <span class="MuConstant">3</span>:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~is <span class="Global">memory*</span><span class="Constant">.1</span> <span class="Delimiter">(</span>/ real.8 <span class="Constant">3</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'divide'"</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"idiv-literal"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Constant">2</span>:integer <span class="Op"><-</span> divide-with-remainder <span class="MuConstant">23</span>:literal <span class="MuConstant">6</span>:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~iso <span class="Global">memory*</span> <span class="Delimiter">(</span>obj <span class="Constant">1</span> <span class="Constant">3</span> <span class="Constant">2</span> <span class="Constant">5</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'divide-with-remainder' performs integer division"</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"dummy-oarg"</span><span class="Delimiter">)</span>
<span class="CommentedCode">;? (set dump-trace*)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span>_ <span class="Constant">2</span>:integer <span class="Op"><-</span> divide-with-remainder <span class="MuConstant">23</span>:literal <span class="MuConstant">6</span>:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~iso <span class="Global">memory*</span> <span class="Delimiter">(</span>obj <span class="Constant">2</span> <span class="Constant">5</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - '_' oarg can ignore some results"</span><span class="Delimiter">))</span>
<span class="CommentedCode">;? (quit)</span>
<span class="Comment">; Basic boolean operations: and, or, not</span>
<span class="Comment">; There are easy ways to encode booleans in binary, but we'll skip past those</span>
<span class="Comment">; details for now.</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"and-literal"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:boolean <span class="Op"><-</span> and <span class="MuConstant">t</span>:literal <span class="MuConstant">nil</span>:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="CommentedCode">;? (set dump-trace*)</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~is <span class="Global">memory*</span><span class="Constant">.1</span> nil<span class="Delimiter">)</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - logical 'and' for booleans"</span><span class="Delimiter">))</span>
<span class="Comment">; Basic comparison operations</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"lt-literal"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:boolean <span class="Op"><-</span> less-than <span class="MuConstant">4</span>:literal <span class="MuConstant">3</span>:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~is <span class="Global">memory*</span><span class="Constant">.1</span> nil<span class="Delimiter">)</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'less-than' inequality operator"</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"le-literal-false"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:boolean <span class="Op"><-</span> lesser-or-equal <span class="MuConstant">4</span>:literal <span class="MuConstant">3</span>:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~is <span class="Global">memory*</span><span class="Constant">.1</span> nil<span class="Delimiter">)</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'lesser-or-equal'"</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"le-literal-true"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:boolean <span class="Op"><-</span> lesser-or-equal <span class="MuConstant">4</span>:literal <span class="MuConstant">4</span>:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~is <span class="Global">memory*</span><span class="Constant">.1</span> t<span class="Delimiter">)</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'lesser-or-equal' returns true for equal operands"</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"le-literal-true-2"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:boolean <span class="Op"><-</span> lesser-or-equal <span class="MuConstant">4</span>:literal <span class="MuConstant">5</span>:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~is <span class="Global">memory*</span><span class="Constant">.1</span> t<span class="Delimiter">)</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'lesser-or-equal' - 2"</span><span class="Delimiter">))</span>
<span class="Comment">; Control flow operations: jump, jump-if, jump-unless</span>
<span class="Comment">; These introduce a new type -- 'offset' -- for literals that refer to memory</span>
<span class="Comment">; locations relative to the current location.</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"jump-skip"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">8</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Identifier">jump</span> <span class="MuConstant">1</span>:offset<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">3</span>:literal<span class="Delimiter">)</span> <span class="Comment">; should be skipped</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Identifier">reply</span><span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="CommentedCode">;? (set dump-trace*)</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~iso <span class="Global">memory*</span> <span class="Delimiter">(</span>obj <span class="Constant">1</span> <span class="Constant">8</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'jump' skips some instructions"</span><span class="Delimiter">))</span>
<span class="CommentedCode">;? (quit)</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"jump-target"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">8</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Identifier">jump</span> <span class="MuConstant">1</span>:offset<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">3</span>:literal<span class="Delimiter">)</span> <span class="Comment">; should be skipped</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Identifier">reply</span><span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">34</span>:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span> <span class="Comment">; never reached</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~iso <span class="Global">memory*</span> <span class="Delimiter">(</span>obj <span class="Constant">1</span> <span class="Constant">8</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'jump' doesn't skip too many instructions"</span><span class="Delimiter">))</span>
<span class="CommentedCode">;? (quit)</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"jump-if-skip"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">1</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:boolean <span class="Op"><-</span> equal <span class="MuConstant">1</span>:literal <span class="Constant">2</span>:integer<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Identifier">jump-if</span> <span class="Constant">1</span>:boolean <span class="MuConstant">1</span>:offset<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">3</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Identifier">reply</span><span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">34</span>:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~iso <span class="Global">memory*</span> <span class="Delimiter">(</span>obj <span class="Constant">1</span> t <span class="Constant">2</span> <span class="Constant">1</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'jump-if' is a conditional 'jump'"</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"jump-if-fallthrough"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:boolean <span class="Op"><-</span> equal <span class="MuConstant">1</span>:literal <span class="MuConstant">2</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Identifier">jump-if</span> <span class="Constant">3</span>:boolean <span class="MuConstant">1</span>:offset<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">3</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Identifier">reply</span><span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">34</span>:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~iso <span class="Global">memory*</span> <span class="Delimiter">(</span>obj <span class="Constant">1</span> nil <span class="Constant">2</span> <span class="Constant">3</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - if 'jump-if's first arg is false, it doesn't skip any instructions"</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"jump-if-backward"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">2</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">1</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Comment">; loop</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> add <span class="Constant">2</span>:integer <span class="Constant">2</span>:integer<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:boolean <span class="Op"><-</span> equal <span class="Constant">1</span>:integer <span class="Constant">2</span>:integer<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Identifier">jump-if</span> <span class="Constant">3</span>:boolean <span class="MuConstant">-3</span>:offset<span class="Delimiter">)</span> <span class="Comment">; to loop</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">4</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">3</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Identifier">reply</span><span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">34</span>:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~iso <span class="Global">memory*</span> <span class="Delimiter">(</span>obj <span class="Constant">1</span> <span class="Constant">2</span> <span class="Constant">2</span> <span class="Constant">4</span> <span class="Constant">3</span> nil <span class="Constant">4</span> <span class="Constant">3</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'jump-if' can take a negative offset to make backward jumps"</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"jump-label"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">2</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">1</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Identifier">loop</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> add <span class="Constant">2</span>:integer <span class="Constant">2</span>:integer<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:boolean <span class="Op"><-</span> equal <span class="Constant">1</span>:integer <span class="Constant">2</span>:integer<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Identifier">jump-if</span> <span class="Constant">3</span>:boolean <span class="Identifier">loop</span>:offset<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">4</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">3</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Identifier">reply</span><span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">34</span>:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="CommentedCode">;? (set dump-trace*)</span>
<span class="CommentedCode">;? (= dump-trace* (obj whitelist '("-")))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~iso <span class="Global">memory*</span> <span class="Delimiter">(</span>obj <span class="Constant">1</span> <span class="Constant">2</span> <span class="Constant">2</span> <span class="Constant">4</span> <span class="Constant">3</span> nil <span class="Constant">4</span> <span class="Constant">3</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'jump-if' can take a negative offset to make backward jumps"</span><span class="Delimiter">))</span>
<span class="CommentedCode">;? (quit)</span>
<span class="Comment">; Data movement relies on addressing modes:</span>
<span class="Comment">; 'direct' - refers to a memory location; default for most types.</span>
<span class="Comment">; 'literal' - directly encoded in the code; implicit for some types like 'offset'.</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"direct-addressing"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">34</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> copy <span class="Constant">1</span>:integer<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~iso <span class="Global">memory*</span> <span class="Delimiter">(</span>obj <span class="Constant">1</span> <span class="Constant">34</span> <span class="Constant">2</span> <span class="Constant">34</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'copy' performs direct addressing"</span><span class="Delimiter">))</span>
<span class="Comment">; 'Indirect' addressing refers to an address stored in a memory location.</span>
<span class="Comment">; Indicated by the metadata 'deref'. Usually requires an address type.</span>
<span class="Comment">; In the test below, the memory location 1 contains '2', so an indirect read</span>
<span class="Comment">; of location 1 returns the value of location 2.</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"indirect-addressing"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer-address <span class="Op"><-</span> copy <span class="MuConstant">2</span>:literal<span class="Delimiter">)</span> <span class="Comment">; unsafe; can't do this in general</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">34</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:integer <span class="Op"><-</span> copy <span class="Constant">1</span>:integer-address/deref<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~iso <span class="Global">memory*</span> <span class="Delimiter">(</span>obj <span class="Constant">1</span> <span class="Constant">2</span> <span class="Constant">2</span> <span class="Constant">34</span> <span class="Constant">3</span> <span class="Constant">34</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'copy' performs indirect addressing"</span><span class="Delimiter">))</span>
<span class="Comment">; Output args can use indirect addressing. In the test below the value is</span>
<span class="Comment">; stored at the location stored in location 1 (i.e. location 2).</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"indirect-addressing-oarg"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer-address <span class="Op"><-</span> copy <span class="MuConstant">2</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">34</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer-address/deref <span class="Op"><-</span> add <span class="Constant">2</span>:integer <span class="MuConstant">2</span>:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~iso <span class="Global">memory*</span> <span class="Delimiter">(</span>obj <span class="Constant">1</span> <span class="Constant">2</span> <span class="Constant">2</span> <span class="Constant">36</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - instructions can perform indirect addressing on output arg"</span><span class="Delimiter">))</span>
<span class="SalientComment">;; Compound data types</span>
<span class="Comment">;</span>
<span class="Comment">; Until now we've dealt with scalar types like integers and booleans and</span>
<span class="Comment">; addresses, where mu looks like other assembly languages. In addition, mu</span>
<span class="Comment">; provides first-class support for compound types: arrays and and-records.</span>
<span class="Comment">;</span>
<span class="Comment">; 'get' accesses fields in and-records</span>
<span class="Comment">; 'index' accesses indices in arrays</span>
<span class="Comment">;</span>
<span class="Comment">; Both operations require knowledge about the types being worked on, so all</span>
<span class="Comment">; types used in mu programs are defined in a single global system-wide table</span>
<span class="Comment">; (see type* in mu.arc for the complete list of types; we'll add to it over</span>
<span class="Comment">; time).</span>
<span class="Comment">; first a sanity check that the table of types is consistent</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>each <span class="Delimiter">(</span>typ typeinfo<span class="Delimiter">)</span> <span class="Global">type*</span>
<span class="Delimiter">(</span>when typeinfo!and-record
<span class="Delimiter">(</span>assert <span class="Delimiter">(</span>is typeinfo!size <span class="Delimiter">(</span>len typeinfo!elems<span class="Delimiter">)))</span>
<span class="Delimiter">(</span>when typeinfo!fields
<span class="Delimiter">(</span>assert <span class="Delimiter">(</span>is typeinfo!size <span class="Delimiter">(</span>len typeinfo!fields<span class="Delimiter">))))))</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"get-record"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">34</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:boolean <span class="Op"><-</span> copy <span class="MuConstant">nil</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:boolean <span class="Op"><-</span> get <span class="Constant">1</span>:integer-boolean-pair <span class="MuConstant">1</span>:offset<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">4</span>:integer <span class="Op"><-</span> get <span class="Constant">1</span>:integer-boolean-pair <span class="MuConstant">0</span>:offset<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="CommentedCode">;? (set dump-trace*)</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~iso <span class="Global">memory*</span> <span class="Delimiter">(</span>obj <span class="Constant">1</span> <span class="Constant">34</span> <span class="Constant">2</span> nil <span class="Constant">3</span> nil <span class="Constant">4</span> <span class="Constant">34</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'get' accesses fields of and-records"</span><span class="Delimiter">))</span>
<span class="CommentedCode">;? (quit)</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"get-indirect"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">34</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:boolean <span class="Op"><-</span> copy <span class="MuConstant">nil</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:integer-boolean-pair-address <span class="Op"><-</span> copy <span class="MuConstant">1</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">4</span>:boolean <span class="Op"><-</span> get <span class="Constant">3</span>:integer-boolean-pair-address/deref <span class="MuConstant">1</span>:offset<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">5</span>:integer <span class="Op"><-</span> get <span class="Constant">3</span>:integer-boolean-pair-address/deref <span class="MuConstant">0</span>:offset<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="CommentedCode">;? (set dump-trace*)</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~iso <span class="Global">memory*</span> <span class="Delimiter">(</span>obj <span class="Constant">1</span> <span class="Constant">34</span> <span class="Constant">2</span> nil <span class="Constant">3</span> <span class="Constant">1</span> <span class="Constant">4</span> nil <span class="Constant">5</span> <span class="Constant">34</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'get' accesses fields of and-record address"</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"get-indirect-repeated"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">34</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">35</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">36</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">4</span>:integer-point-pair-address <span class="Op"><-</span> copy <span class="MuConstant">1</span>:literal<span class="Delimiter">)</span> <span class="Comment">; unsafe</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">5</span>:integer-point-pair-address-address <span class="Op"><-</span> copy <span class="MuConstant">4</span>:literal<span class="Delimiter">)</span> <span class="Comment">; unsafe</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">6</span>:integer-integer-pair <span class="Op"><-</span> get <span class="Constant">5</span>:integer-point-pair-address-address/deref/deref <span class="MuConstant">1</span>:offset<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">8</span>:integer <span class="Op"><-</span> get <span class="Constant">5</span>:integer-point-pair-address-address/deref/deref <span class="MuConstant">0</span>:offset<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~memory-contains <span class="Constant">6</span> <span class="Delimiter">'(</span><span class="Constant">35</span> <span class="Constant">36</span> <span class="Constant">34</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'get' can deref multiple times"</span><span class="Delimiter">))</span>
<span class="CommentedCode">;? (quit)</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"get-compound-field"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">34</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">35</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">36</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">4</span>:integer-integer-pair <span class="Op"><-</span> get <span class="Constant">1</span>:integer-point-pair <span class="MuConstant">1</span>:offset<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~iso <span class="Global">memory*</span> <span class="Delimiter">(</span>obj <span class="Constant">1</span> <span class="Constant">34</span> <span class="Constant">2</span> <span class="Constant">35</span> <span class="Constant">3</span> <span class="Constant">36</span> <span class="Constant">4</span> <span class="Constant">35</span> <span class="Constant">5</span> <span class="Constant">36</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'get' accesses fields spanning multiple locations"</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"get-address"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">34</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:boolean <span class="Op"><-</span> copy <span class="MuConstant">t</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:boolean-address <span class="Op"><-</span> get-address <span class="Constant">1</span>:integer-boolean-pair <span class="MuConstant">1</span>:offset<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~iso <span class="Global">memory*</span> <span class="Delimiter">(</span>obj <span class="Constant">1</span> <span class="Constant">34</span> <span class="Constant">2</span> t <span class="Constant">3</span> <span class="Constant">2</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'get-address' returns address of fields of and-records"</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"get-address-indirect"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">34</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:boolean <span class="Op"><-</span> copy <span class="MuConstant">t</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:integer-boolean-pair-address <span class="Op"><-</span> copy <span class="MuConstant">1</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">4</span>:boolean-address <span class="Op"><-</span> get-address <span class="Constant">3</span>:integer-boolean-pair-address/deref <span class="MuConstant">1</span>:offset<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~iso <span class="Global">memory*</span> <span class="Delimiter">(</span>obj <span class="Constant">1</span> <span class="Constant">34</span> <span class="Constant">2</span> t <span class="Constant">3</span> <span class="Constant">1</span> <span class="Constant">4</span> <span class="Constant">2</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'get-address' accesses fields of and-record address"</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"index-literal"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">2</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">23</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:boolean <span class="Op"><-</span> copy <span class="MuConstant">nil</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">4</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">24</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">5</span>:boolean <span class="Op"><-</span> copy <span class="MuConstant">t</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">6</span>:integer-boolean-pair <span class="Op"><-</span> index <span class="Constant">1</span>:integer-boolean-pair-array <span class="MuConstant">1</span>:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~iso <span class="Global">memory*</span> <span class="Delimiter">(</span>obj <span class="Constant">1</span> <span class="Constant">2</span> <span class="Constant">2</span> <span class="Constant">23</span> <span class="Constant">3</span> nil <span class="Constant">4</span> <span class="Constant">24</span> <span class="Constant">5</span> t <span class="Constant">6</span> <span class="Constant">24</span> <span class="Constant">7</span> t<span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'index' accesses indices of arrays"</span><span class="Delimiter">))</span>
<span class="CommentedCode">;? (quit)</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"index-direct"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">2</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">23</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:boolean <span class="Op"><-</span> copy <span class="MuConstant">nil</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">4</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">24</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">5</span>:boolean <span class="Op"><-</span> copy <span class="MuConstant">t</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">6</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">1</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">7</span>:integer-boolean-pair <span class="Op"><-</span> index <span class="Constant">1</span>:integer-boolean-pair-array <span class="Constant">6</span>:integer<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~iso <span class="Global">memory*</span> <span class="Delimiter">(</span>obj <span class="Constant">1</span> <span class="Constant">2</span> <span class="Constant">2</span> <span class="Constant">23</span> <span class="Constant">3</span> nil <span class="Constant">4</span> <span class="Constant">24</span> <span class="Constant">5</span> t <span class="Constant">6</span> <span class="Constant">1</span> <span class="Constant">7</span> <span class="Constant">24</span> <span class="Constant">8</span> t<span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'index' accesses indices of arrays"</span><span class="Delimiter">))</span>
<span class="CommentedCode">;? (quit)</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"index-indirect"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">2</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">23</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:boolean <span class="Op"><-</span> copy <span class="MuConstant">nil</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">4</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">24</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">5</span>:boolean <span class="Op"><-</span> copy <span class="MuConstant">t</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">6</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">1</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">7</span>:integer-boolean-pair-array-address <span class="Op"><-</span> copy <span class="MuConstant">1</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">8</span>:integer-boolean-pair <span class="Op"><-</span> index <span class="Constant">7</span>:integer-boolean-pair-array-address/deref <span class="Constant">6</span>:integer<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="CommentedCode">;? (= dump-trace* (obj blacklist '("sz" "m" "setm" "addr" "cvt0" "cvt1")))</span>
<span class="CommentedCode">;? (set dump-trace*)</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~iso <span class="Global">memory*</span> <span class="Delimiter">(</span>obj <span class="Constant">1</span> <span class="Constant">2</span> <span class="Constant">2</span> <span class="Constant">23</span> <span class="Constant">3</span> nil <span class="Constant">4</span> <span class="Constant">24</span> <span class="Constant">5</span> t <span class="Constant">6</span> <span class="Constant">1</span> <span class="Constant">7</span> <span class="Constant">1</span> <span class="Constant">8</span> <span class="Constant">24</span> <span class="Constant">9</span> t<span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'index' accesses indices of array address"</span><span class="Delimiter">))</span>
<span class="CommentedCode">;? (quit)</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"index-indirect-multiple"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">4</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">23</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">24</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">4</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">25</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">5</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">26</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">6</span>:integer-array-address <span class="Op"><-</span> copy <span class="MuConstant">1</span>:literal<span class="Delimiter">)</span> <span class="Comment">; unsafe</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">7</span>:integer-array-address-address <span class="Op"><-</span> copy <span class="MuConstant">6</span>:literal<span class="Delimiter">)</span> <span class="Comment">; unsafe</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">8</span>:integer <span class="Op"><-</span> index <span class="Constant">7</span>:integer-array-address-address/deref/deref <span class="MuConstant">1</span>:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~is <span class="Global">memory*</span><span class="Constant">.8</span> <span class="Constant">24</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'index' can deref multiple times"</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"index-address"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">2</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">23</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:boolean <span class="Op"><-</span> copy <span class="MuConstant">nil</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">4</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">24</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">5</span>:boolean <span class="Op"><-</span> copy <span class="MuConstant">t</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">6</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">1</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">7</span>:integer-boolean-pair-address <span class="Op"><-</span> index-address <span class="Constant">1</span>:integer-boolean-pair-array <span class="Constant">6</span>:integer<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~iso <span class="Global">memory*</span> <span class="Delimiter">(</span>obj <span class="Constant">1</span> <span class="Constant">2</span> <span class="Constant">2</span> <span class="Constant">23</span> <span class="Constant">3</span> nil <span class="Constant">4</span> <span class="Constant">24</span> <span class="Constant">5</span> t <span class="Constant">6</span> <span class="Constant">1</span> <span class="Constant">7</span> <span class="Constant">4</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'index-address' returns addresses of indices of arrays"</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"index-address-indirect"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">2</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">23</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:boolean <span class="Op"><-</span> copy <span class="MuConstant">nil</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">4</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">24</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">5</span>:boolean <span class="Op"><-</span> copy <span class="MuConstant">t</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">6</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">1</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">7</span>:integer-boolean-pair-array-address <span class="Op"><-</span> copy <span class="MuConstant">1</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">8</span>:integer-boolean-pair-address <span class="Op"><-</span> index-address <span class="Constant">7</span>:integer-boolean-pair-array-address/deref <span class="Constant">6</span>:integer<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~iso <span class="Global">memory*</span> <span class="Delimiter">(</span>obj <span class="Constant">1</span> <span class="Constant">2</span> <span class="Constant">2</span> <span class="Constant">23</span> <span class="Constant">3</span> nil <span class="Constant">4</span> <span class="Constant">24</span> <span class="Constant">5</span> t <span class="Constant">6</span> <span class="Constant">1</span> <span class="Constant">7</span> <span class="Constant">1</span> <span class="Constant">8</span> <span class="Constant">4</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'index-address' returns addresses of indices of array addresses"</span><span class="Delimiter">))</span>
<span class="Comment">; Array values know their length. Record lengths are saved in the types table.</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"len-array"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">2</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">23</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:boolean <span class="Op"><-</span> copy <span class="MuConstant">nil</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">4</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">24</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">5</span>:boolean <span class="Op"><-</span> copy <span class="MuConstant">t</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">6</span>:integer <span class="Op"><-</span> length <span class="Constant">1</span>:integer-boolean-pair-array<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~is <span class="Global">memory*</span><span class="Constant">.6</span> <span class="Constant">2</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'length' of array"</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"len-array-indirect"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">2</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">23</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:boolean <span class="Op"><-</span> copy <span class="MuConstant">nil</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">4</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">24</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">5</span>:boolean <span class="Op"><-</span> copy <span class="MuConstant">t</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">6</span>:integer-address <span class="Op"><-</span> copy <span class="MuConstant">1</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">7</span>:integer <span class="Op"><-</span> length <span class="Constant">6</span>:integer-boolean-pair-array-address/deref<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="CommentedCode">;? (set dump-trace*)</span>
<span class="CommentedCode">;? (= dump-trace* (obj blacklist '("sz" "m" "setm" "addr" "cvt0" "cvt1")))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~is <span class="Global">memory*</span><span class="Constant">.7</span> <span class="Constant">2</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'length' of array address"</span><span class="Delimiter">))</span>
<span class="Comment">; 'sizeof' is a helper to determine the amount of memory required by a type.</span>
<span class="Comment">; Only for non-arrays.</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"sizeof-record"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> sizeof integer-boolean-pair:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~is <span class="Global">memory*</span><span class="Constant">.1</span> <span class="Constant">2</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'sizeof' returns space required by arg"</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"sizeof-record-not-len"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> sizeof integer-point-pair:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>is <span class="Global">memory*</span><span class="Constant">.1</span> <span class="Constant">2</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'sizeof' is different from number of elems"</span><span class="Delimiter">))</span>
<span class="Comment">; Regardless of a type's length, you can move it around just like a primitive.</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"copy-record"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">34</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:boolean <span class="Op"><-</span> copy <span class="MuConstant">nil</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">4</span>:boolean <span class="Op"><-</span> copy <span class="MuConstant">t</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:integer-boolean-pair <span class="Op"><-</span> copy <span class="Constant">1</span>:integer-boolean-pair<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~iso <span class="Global">memory*</span> <span class="Delimiter">(</span>obj <span class="Constant">1</span> <span class="Constant">34</span> <span class="Constant">2</span> nil <span class="Constant">3</span> <span class="Constant">34</span> <span class="Constant">4</span> nil<span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - ops can operate on records spanning multiple locations"</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"copy-record2"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">34</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">35</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">36</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">4</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">0</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">5</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">0</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">6</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">0</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">4</span>:integer-point-pair <span class="Op"><-</span> copy <span class="Constant">1</span>:integer-point-pair<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="CommentedCode">;? (= dump-trace* (obj whitelist '("run" "sizeof")))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~iso <span class="Global">memory*</span> <span class="Delimiter">(</span>obj <span class="Constant">1</span> <span class="Constant">34</span> <span class="Constant">2</span> <span class="Constant">35</span> <span class="Constant">3</span> <span class="Constant">36</span>
<span class="Comment">; result</span>
<span class="Constant">4</span> <span class="Constant">34</span> <span class="Constant">5</span> <span class="Constant">35</span> <span class="Constant">6</span> <span class="Constant">36</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - ops can operate on records with fields spanning multiple locations"</span><span class="Delimiter">))</span>
<span class="Delimiter">)</span> <span class="Comment">; section 20</span>
<span class="Delimiter">(</span>section <span class="Constant">100</span>
<span class="Comment">; A special kind of record is the 'tagged type'. It lets us represent</span>
<span class="Comment">; dynamically typed values, which save type information in memory rather than</span>
<span class="Comment">; in the code to use them. This will let us do things like create heterogenous</span>
<span class="Comment">; lists containing both integers and strings. Tagged values admit two</span>
<span class="Comment">; operations:</span>
<span class="Comment">;</span>
<span class="Comment">; 'save-type' - turns a regular value into a tagged-value of the appropriate type</span>
<span class="Comment">; 'maybe-coerce' - turns a tagged value into a regular value if the type matches</span>
<span class="Comment">;</span>
<span class="Comment">; The payload of a tagged value must occupy just one location. Save pointers</span>
<span class="Comment">; to records.</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"tagged-value"</span><span class="Delimiter">)</span>
<span class="CommentedCode">;? (= dump-trace* (obj blacklist '("sz" "m" "setm" "addr" "cvt0" "cvt1")))</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:type <span class="Op"><-</span> copy integer:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">34</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:integer <span class="Constant">4</span>:boolean <span class="Op"><-</span> maybe-coerce <span class="Constant">1</span>:tagged-value integer:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="CommentedCode">;? (set dump-trace*)</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn completed-routines*)</span>
<span class="Delimiter">(</span>each routine <span class="Global">completed-routines*</span>
<span class="Delimiter">(</span>aif rep.routine!error <span class="Delimiter">(</span>prn <span class="Constant">"error - "</span> it<span class="Delimiter">)))</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span><span class="Normal">or</span> <span class="Delimiter">(</span>~is <span class="Global">memory*</span><span class="Constant">.3</span> <span class="Constant">34</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>~is <span class="Global">memory*</span><span class="Constant">.4</span> t<span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'maybe-coerce' copies value only if type tag matches"</span><span class="Delimiter">))</span>
<span class="CommentedCode">;? (quit)</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"tagged-value-2"</span><span class="Delimiter">)</span>
<span class="CommentedCode">;? (set dump-trace*)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:type <span class="Op"><-</span> copy integer-address:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">34</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:boolean <span class="Constant">4</span>:boolean <span class="Op"><-</span> maybe-coerce <span class="Constant">1</span>:tagged-value boolean:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span><span class="Normal">or</span> <span class="Delimiter">(</span>~is <span class="Global">memory*</span><span class="Constant">.3</span> <span class="Constant">0</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>~is <span class="Global">memory*</span><span class="Constant">.4</span> nil<span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'maybe-coerce' doesn't copy value when type tag doesn't match"</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"save-type"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">34</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:tagged-value <span class="Op"><-</span> save-type <span class="Constant">1</span>:integer<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~iso <span class="Global">memory*</span> <span class="Delimiter">(</span>obj <span class="Constant">1</span> <span class="Constant">34</span> <span class="Constant">2</span> <span class="Delimiter">'</span>integer <span class="Constant">3</span> <span class="Constant">34</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'save-type' saves the type of a value at runtime, turning it into a tagged-value"</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"init-tagged-value"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> copy <span class="MuConstant">34</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:tagged-value-address <span class="Op"><-</span> init-tagged-value integer:literal <span class="Constant">1</span>:integer<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:integer <span class="Constant">4</span>:boolean <span class="Op"><-</span> maybe-coerce <span class="Constant">2</span>:tagged-value-address/deref integer:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="CommentedCode">;? (= dump-trace* (obj blacklist '("sz" "m" "setm" "addr" "cvt0" "cvt1" "sizeof")))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span><span class="Normal">or</span> <span class="Delimiter">(</span>~is <span class="Global">memory*</span><span class="Constant">.3</span> <span class="Constant">34</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>~is <span class="Global">memory*</span><span class="Constant">.4</span> t<span class="Delimiter">))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'init-tagged-value' is the converse of 'maybe-coerce'"</span><span class="Delimiter">))</span>
<span class="CommentedCode">;? (quit)</span>
<span class="Comment">; Now that we can package values together with their types, we can construct a</span>
<span class="Comment">; dynamically typed list.</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"list"</span><span class="Delimiter">)</span>
<span class="CommentedCode">;? (set dump-trace*)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Comment">; 1 points at first node: tagged-value (int 34)</span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:list-address <span class="Op"><-</span> new list:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">2</span>:tagged-value-address <span class="Op"><-</span> list-value-address <span class="Constant">1</span>:list-address<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:type-address <span class="Op"><-</span> get-address <span class="Constant">2</span>:tagged-value-address/deref type:offset<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">3</span>:type-address/deref <span class="Op"><-</span> copy integer:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">4</span>:location <span class="Op"><-</span> get-address <span class="Constant">2</span>:tagged-value-address/deref payload:offset<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">4</span>:location/deref <span class="Op"><-</span> copy <span class="MuConstant">34</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">5</span>:list-address-address <span class="Op"><-</span> get-address <span class="Constant">1</span>:list-address/deref cdr:offset<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">5</span>:list-address-address/deref <span class="Op"><-</span> new list:literal<span class="Delimiter">)</span></span>
<span class="Comment">; 6 points at second node: tagged-value (boolean t)</span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">6</span>:list-address <span class="Op"><-</span> copy <span class="Constant">5</span>:list-address-address/deref<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">7</span>:tagged-value-address <span class="Op"><-</span> list-value-address <span class="Constant">6</span>:list-address<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">8</span>:type-address <span class="Op"><-</span> get-address <span class="Constant">7</span>:tagged-value-address/deref type:offset<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">8</span>:type-address/deref <span class="Op"><-</span> copy boolean:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">9</span>:location <span class="Op"><-</span> get-address <span class="Constant">7</span>:tagged-value-address/deref payload:offset<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">9</span>:location/deref <span class="Op"><-</span> copy <span class="MuConstant">t</span>:literal<span class="Delimiter">)</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">10</span>:list-address <span class="Op"><-</span> get <span class="Constant">6</span>:list-address/deref <span class="MuConstant">1</span>:offset<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="Delimiter">(</span><span class="Normal">let</span> routine make-routine!main
<span class="Delimiter">(</span>enq routine <span class="Global">running-routines*</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span><span class="Normal">let</span> first rep.routine!alloc
<span class="CommentedCode">;? (= dump-trace* (obj whitelist '("run")))</span>
<span class="CommentedCode">;? (set dump-trace*)</span>
<span class="Delimiter">(</span>run<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span>each routine <span class="Global">completed-routines*</span>
<span class="Delimiter">(</span>aif rep.routine!error <span class="Delimiter">(</span>prn <span class="Constant">"error - "</span> it<span class="Delimiter">)))</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span><span class="Normal">or</span> <span class="Delimiter">(</span>~all first <span class="Delimiter">(</span>map <span class="Global">memory*</span> <span class="Delimiter">'(</span><span class="Constant">1</span> <span class="Constant">2</span> <span class="Constant">3</span><span class="Delimiter">)))</span>
<span class="Delimiter">(</span>~is <span class="Global">memory*</span>.first <span class="Delimiter">'</span>integer<span class="Delimiter">)</span>
<span class="Delimiter">(</span>~is <span class="Global">memory*</span><span class="Constant">.4</span> <span class="Delimiter">(</span>+ first <span class="Constant">1</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>~is <span class="Delimiter">(</span><span class="Global">memory*</span> <span class="Delimiter">(</span>+ first <span class="Constant">1</span><span class="Delimiter">))</span> <span class="Constant">34</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>~is <span class="Global">memory*</span><span class="Constant">.5</span> <span class="Delimiter">(</span>+ first <span class="Constant">2</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span><span class="Normal">let</span> second <span class="Global">memory*</span><span class="Constant">.6</span>
<span class="Delimiter">(</span><span class="Normal">or</span>
<span class="Delimiter">(</span>~is <span class="Delimiter">(</span><span class="Global">memory*</span> <span class="Delimiter">(</span>+ first <span class="Constant">2</span><span class="Delimiter">))</span> second<span class="Delimiter">)</span>
<span class="Delimiter">(</span>~all second <span class="Delimiter">(</span>map <span class="Global">memory*</span> <span class="Delimiter">'(</span><span class="Constant">6</span> <span class="Constant">7</span> <span class="Constant">8</span><span class="Delimiter">)))</span>
<span class="Delimiter">(</span>~is <span class="Global">memory*</span>.second <span class="Delimiter">'</span>boolean<span class="Delimiter">)</span>
<span class="Delimiter">(</span>~is <span class="Global">memory*</span><span class="Constant">.9</span> <span class="Delimiter">(</span>+ second <span class="Constant">1</span><span class="Delimiter">))</span>
<span class="Delimiter">(</span>~is <span class="Delimiter">(</span><span class="Global">memory*</span> <span class="Delimiter">(</span>+ second <span class="Constant">1</span><span class="Delimiter">))</span> t<span class="Delimiter">)</span>
<span class="Delimiter">(</span>~is <span class="Global">memory*</span><span class="Constant">.10</span> nil<span class="Delimiter">))))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - lists can contain elements of different types"</span><span class="Delimiter">))))</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function test2 <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">10</span>:list-address <span class="Op"><-</span> list-next <span class="Constant">1</span>:list-address<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="CommentedCode">;? (set dump-trace*)</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>test2<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span>each routine <span class="Global">completed-routines*</span>
<span class="Delimiter">(</span>aif rep.routine!error <span class="Delimiter">(</span>prn <span class="Constant">"error - "</span> it<span class="Delimiter">)))</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span>~is <span class="Global">memory*</span><span class="Constant">.10</span> <span class="Global">memory*</span><span class="Constant">.6</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'list-next can move a list pointer to the next node"</span><span class="Delimiter">))</span>
<span class="CommentedCode">;? (quit)</span>
<span class="Comment">; 'init-list' takes a variable number of args and constructs a list containing</span>
<span class="Comment">; them. Just integers for now.</span>
<span class="Delimiter">(</span>reset<span class="Delimiter">)</span>
<span class="Delimiter">(</span>new-trace <span class="Constant">"init-list"</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>add-code
<span class="Mu"><span class="Delimiter">'((</span>function main <span class="Delimiter">[</span></span>
<span class="Mu"><span class="Delimiter">(</span><span class="Constant">1</span>:integer <span class="Op"><-</span> init-list <span class="MuConstant">3</span>:literal <span class="MuConstant">4</span>:literal <span class="MuConstant">5</span>:literal<span class="Delimiter">)</span></span>
<span class="Delimiter">])))</span>
<span class="CommentedCode">;? (= dump-trace* (obj blacklist '("sz" "m" "setm" "addr" "cvt0" "cvt1" "sizeof")))</span>
<span class="Delimiter">(</span>run <span class="Delimiter">'</span>main<span class="Delimiter">)</span>
<span class="CommentedCode">;? (prn memory*)</span>
<span class="Delimiter">(</span><span class="Normal">let</span> first <span class="Global">memory*</span><span class="Constant">.1</span>
<span class="CommentedCode">;? (prn first)</span>
<span class="Delimiter">(</span><span class="Normal">if</span> <span class="Delimiter">(</span><span class="Normal">or</span> <span class="Delimiter">(</span>~is <span class="Global">memory*</span>.first <span class="Delimiter">'</span>integer<span class="Delimiter">)</span>
<span class="Delimiter">(</span>~is <span class="Delimiter">(</span><span class="Global">memory*</span> <span class="Delimiter">(</span>+ first <span class="Constant">1</span><span class="Delimiter">))</span> <span class="Constant">3</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span><span class="Normal">let</span> second <span class="Delimiter">(</span><span class="Global">memory*</span> <span class="Delimiter">(</span>+ first <span class="Constant">2</span><span class="Delimiter">))</span>
<span class="CommentedCode">;? (prn second)</span>
<span class="Delimiter">(</span><span class="Normal">or</span> <span class="Delimiter">(</span>~is <span class="Global">memory*</span>.second <span class="Delimiter">'</span>integer<span class="Delimiter">)</span>
<span class="Delimiter">(</span>~is <span class="Delimiter">(</span><span class="Global">memory*</span> <span class="Delimiter">(</span>+ second <span class="Constant">1</span><span class="Delimiter">))</span> <span class="Constant">4</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span><span class="Normal">let</span> third <span class="Delimiter">(</span><span class="Global">memory*</span> <span class="Delimiter">(</span>+ second <span class="Constant">2</span><span class="Delimiter">))</span>
<span class="CommentedCode">;? (prn third)</span>
<span class="Delimiter">(</span><span class="Normal">or</span> <span class="Delimiter">(</span>~is <span class="Global">memory*</span>.third <span class="Delimiter">'</span>integer<span class="Delimiter">)</span>
<span class="Delimiter">(</span>~is <span class="Delimiter">(</span><span class="Global">memory*</span> <span class="Delimiter">(</span>+ third <span class="Constant">1</span><span class="Delimiter">))</span> <span class="Constant">5</span><span class="Delimiter">)</span>
<span class="Delimiter">(</span>~is <span class="Delimiter">(</span><span class="Global">memory*</span> <span class="Delimiter">(</span>+ third <span class="Constant">2</span><span class="Delimiter">)</span> nil<span class="Delimiter">)))))))</span>
<span class="Delimiter">(</span>prn <span class="Constant">"F - 'init-list' can construct a list of integers"</span><span class="Delimiter">)))</span>
<span class="Delimiter">)</span> <span class="Comment">; section 100</span>
<span class="Delimiter">(</span>section <span class="Constant">20</span>
<span class="SalientComment">;; Functions</span>
<span class="Comment">;</span>
<span class="Comment">; Just like the table of types is centralized, functions are conceptualized as</span>