about summary refs log tree commit diff stats
path: root/010vm.cc
Commit message (Collapse)AuthorAgeFilesLines
* 6888Kartik Agaram2020-09-271-1/+1
| | | | Teach `bootstrap translate` about the new /xm32 and /x32 arguments.
* 6886 - floating-point divisionKartik Agaram2020-09-271-0/+6
|
* 6885 - starting on floating-point instructionsKartik Agaram2020-09-271-3/+12
| | | | | | | | | I spent some time deciding on the instructions. x87 is a stack ISA, so not a good fit for the rest of SubX. So we use SSE instead. They operate on 32-bit floats, which seems like a good fit. SSE has a bunch of instructions for operating on up to 4 floats at once. We'll ignore all that and just focus on so-called scalar instructions.
* 6397Kartik Agaram2020-05-241-0/+397
| | | | | Drop '---' section boundaries from filenames. I noticed them confusing tab-completion for certain advanced shell setups.
* 5485 - promote SubX to top-levelKartik Agaram2019-07-271-900/+0
|
* 4428Kartik Agaram2018-07-261-0/+2
| | | | Fix CI :(
* 4421Kartik Agaram2018-07-261-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Clean up the rat's nest that all my trace management globals had gradually turned into. a) Get rid of 'Start_tracing'. Horryibly named, I don't know how I missed that until now. b) Never use START_TRACING_UNTIL_END_OF_SCOPE in main(). It's confusing to combine it with atexit(delete Trace_stream), because the atexit() never has to run. Instead we'll just manually initialize Trace_stream and let atexit() clean up. c) If we run tests we only want a trace for the test run itself. So delete the Trace_stream that was initialized at the top of main -- once it's clear we had no load-time errors. d) Clean up horribly "Load Recipes" waypoints, combine them with the better name, "Mu Prelude". Putting these together, we have the following manual tests: - CFLAGS=-g mu x.mu Should not create last_run. - CFLAGS=-g mu --trace x.mu Should create last_run. Should write it out exactly once. - CFLAGS=-g mu --trace x.mu # when x.mu has an error Should create last_run. Should write it out exactly once. - CFLAGS=-g mu --trace test copy_literal # C test Should create last_run. Should write it out exactly once. - CFLAGS=-g mu --trace test recipe_with_header # Mu test Should create last_run. Should write it out exactly once. I don't know how to automate these scenarios yet. We need a way to run our build toolchain atop our stack.
* 4417Kartik Agaram2018-07-261-1/+1
| | | | Audit poor uses of 'cout'.
* 4272 - type-check variables in non-local spacesKartik Agaram2018-06-251-0/+2
| | | | | | So far we only checked if a single recipe used a variable with multiple types in any single space. Now we also ensure that the types deduced for a variable in a space are identical across recipes.
* 4243Kartik Agaram2018-05-121-11/+16
|
* 4241Kartik Agaram2018-05-121-2/+2
| | | | | | | | | | | | | | Comparing types by value rather than name seems a bit cleaner. It isn't noticeably faster, though. 4178 - refcount-based memory management 3:27 3:18 3:15 3:15 3:15 4179 - no more abandon 2:13 2:13 2:12 2:11 2:09 2:10 4239 1:42 1:41 1:51 1:43 1:43 1:41 4241 (this commit) 1:53 1:45 1:43 1:43 1:42 1:42
* 4240Kartik Agaram2018-05-121-1/+1
|
* 4223Kartik K. Agaram2018-03-141-0/+1
|
* 4162Kartik K. Agaram2017-12-221-0/+25
|
* 3966Kartik K. Agaram2017-07-091-3/+3
|
* 3877Kartik K. Agaram2017-05-261-7/+2
|
* 3876Kartik K. Agaram2017-05-211-0/+1
| | | | Thanks Ella Couch for reporting this issue.
* 3872Kartik K. Agaram2017-05-201-0/+14
| | | | Starting to look for lack of organization in the edit/ app.
* 3848Kartik K. Agaram2017-05-061-6/+3
| | | | | Improve an error message. Still lots of room for improving how we render reagents in errors.
* 3809Kartik K. Agaram2017-04-041-1/+2
|
* 3744Kartik K. Agaram2017-02-071-1/+0
| | | | | | Undo 3743. Really any time we create new instructions from whole cloth during rewriting or transform, the whole notion of 'original name' goes out the window. Pointless trying to fight that fact of life.
* 3743Kartik K. Agaram2017-02-071-0/+1
| | | | | | | | One way to ensure we always set old_name is to create a method to initialize names as opposed to just assigning them. Still not ideal because we still assign directly most of the time, so it's easy to forget.
* 3742 - move instruction.old_name to a later layerKartik K. Agaram2017-02-061-2/+0
| | | | | | The drawback of this is that we forget to initialize old_name when we create instructions out of whole cloth in a few places. But this problem already existed..
* 3741Kartik K. Agaram2017-02-061-12/+20
| | | | Eliminate a long-standing under-abstraction.
* 3740Kartik K. Agaram2017-02-061-1/+2
|
* 3739Kartik K. Agaram2017-02-061-1/+11
|
* 3666Kartik K. Agaram2016-11-111-0/+2
| | | | Fix a memory leak.
* 3665Kartik K. Agaram2016-11-111-22/+22
|
* 3663 - fix a refcounting bug: '(type)' != 'type'Kartik K. Agaram2016-11-101-18/+49
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This was a large commit, and most of it is a follow-up to commit 3309, undoing what is probably the final ill-considered optimization I added to s-expressions in Mu: I was always representing (a b c) as (a b . c), etc. That is now gone. Why did I need to take it out? The key problem was the error silently ignored in layer 30. That was causing size_of("(type)") to silently return garbage rather than loudly complain (assuming 'type' was a simple type). But to take it out I had to modify types_strictly_match (layer 21) to actually strictly match and not just do a prefix match. In the process of removing the prefix match, I had to make extracting recipe types from recipe headers more robust. So far it only matched the first element of each ingredient's type; these matched: (recipe address:number -> address:number) (recipe address -> address) I didn't notice because the dotted notation optimization was actually representing this as: (recipe address:number -> address number) --- One final little thing in this commit: I added an alias for 'assert' called 'assert_for_now', to indicate that I'm not sure something's really an invariant, that it might be triggered by (invalid) user programs, and so require more thought on error handling down the road. But this may well be an ill-posed distinction. It may be overwhelmingly uneconomic to continually distinguish between model invariants and error states for input. I'm starting to grow sympathetic to Google Analytics's recent approach of just banning assertions altogether. We'll see..
* 3561Kartik K. Agaram2016-10-221-5/+5
|
* 3560Kartik K. Agaram2016-10-221-1/+1
|
* 3549Kartik K. Agaram2016-10-221-1/+1
| | | | | | | | | | | | | | | | | | More consistent definitions for jump targets and waypoints. 1. A label is a word starting with something other than a letter or digit or '$'. 2. A waypoint is a label that starts with '<' and ends with '>'. It has no restrictions. A recipe can define any number of waypoints, and recipes can have duplicate waypoints. 3. The special labels '{' and '}' can also be duplicated any number of times in a recipe. The only constraint on them is that they have to balance in any recipe. Every '{' must be followed by a matching '}'. 4. All other labels are 'jump targets'. You can't have duplicate jump targets in a recipe; that would make jumps ambiguous.
* 3522Kartik K. Agaram2016-10-191-20/+20
|
* 3408Kartik K. Agaram2016-09-221-0/+4
|
* 3313Kartik K. Agaram2016-09-101-0/+83
| | | | | | | Allow type-trees to be ordered in some consistent fashion. This could be quite inefficient since we often end up comparing the four sub-trees of the two arguments in 4 different ways. So far it isn't much of a time sink.
* 3310Kartik K. Agaram2016-09-101-1/+2
| | | | | Turns out the slowdown reported in 3309 was almost entirely due to commit 3305: supporting extremely small floating point numbers.
* 3309Kartik K. Agaram2016-09-091-73/+88
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rip out everything to fix one failing unit test (commit 3290; type abbreviations). This commit does several things at once that I couldn't come up with a clean way to unpack: A. It moves to a new representation for type trees without changing the actual definition of the `type_tree` struct. B. It adds unit tests for our type metadata precomputation, so that errors there show up early and in a simpler setting rather than dying when we try to load Mu code. C. It fixes a bug, guarding against infinite loops when precomputing metadata for recursive shape-shifting containers. To do this it uses a dumb way of comparing type_trees, comparing their string representations instead. That is likely incredibly inefficient. Perhaps due to C, this commit has made Mu incredibly slow. Running all tests for the core and the edit/ app now takes 6.5 minutes rather than 3.5 minutes. == more notes and details I've been struggling for the past week now to back out of a bad design decision, a premature optimization from the early days: storing atoms directly in the 'value' slot of a cons cell rather than creating a special 'atom' cons cell and storing it on the 'left' slot. In other words, if a cons cell looks like this: o / | \ left val right ..then the type_tree (a b c) used to look like this (before this commit): o | \ a o | \ b o | \ c null ..rather than like this 'classic' approach to s-expressions which never mixes val and right (which is what we now have): o / \ o o | / \ a o o | / \ b o null | c The old approach made several operations more complicated, most recently the act of replacing a (possibly atom/leaf) sub-tree with another. That was the final straw that got me to realize the contortions I was going through to save a few type_tree nodes (cons cells). Switching to the new approach was hard partly because I've been using the old approach for so long and type_tree manipulations had pervaded everything. Another issue I ran into was the realization that my layers were not cleanly separated. Key parts of early layers (precomputing type metadata) existed purely for far later ones (shape-shifting types). Layers I got repeatedly stuck at: 1. the transform for precomputing type sizes (layer 30) 2. type-checks on merge instructions (layer 31) 3. the transform for precomputing address offsets in types (layer 36) 4. replace operations in supporting shape-shifting recipes (layer 55) After much thrashing I finally noticed that it wasn't the entirety of these layers that was giving me trouble, but just the type metadata precomputation, which had bugs that weren't manifesting until 30 layers later. Or, worse, when loading .mu files before any tests had had a chance to run. A common failure mode was running into types at run time that I hadn't precomputed metadata for at transform time. Digging into these bugs got me to realize that what I had before wasn't really very good, but a half-assed heuristic approach that did a whole lot of extra work precomputing metadata for utterly meaningless types like `((address number) 3)` which just happened to be part of a larger type like `(array (address number) 3)`. So, I redid it all. I switched the representation of types (because the old representation made unit tests difficult to retrofit) and added unit tests to the metadata precomputation. I also made layer 30 only do the minimal metadata precomputation it needs for the concepts introduced until then. In the process, I also made the precomputation more correct than before, and added hooks in the right place so that I could augment the logic when I introduced shape-shifting containers. == lessons learned There's several levels of hygiene when it comes to layers: 1. Every layer introduces precisely what it needs and in the simplest way possible. If I was building an app until just that layer, nothing would seem over-engineered. 2. Some layers are fore-shadowing features in future layers. Sometimes this is ok. For example, layer 10 foreshadows containers and arrays and so on without actually supporting them. That is a net win because it lets me lay out the core of Mu's data structures out in one place. But if the fore-shadowing gets too complex things get nasty. Not least because it can be hard to write unit tests for features before you provide the plumbing to visualize and manipulate them. 3. A layer is introducing features that are tested only in later layers. 4. A layer is introducing features with tests that are invalidated in later layers. (This I knew from early on to be an obviously horrendous idea.) Summary: avoid Level 2 (foreshadowing layers) as much as possible. Tolerate it indefinitely for small things where the code stays simple over time, but become strict again when things start to get more complex. Level 3 is mostly a net lose, but sometimes it can be expedient (a real case of the usually grossly over-applied term "technical debt"), and it's better than the conventional baseline of no layers and no scenarios. Just clean it up as soon as possible. Definitely avoid layer 4 at any time. == minor lessons Avoid unit tests for trivial things, write scenarios in context as much as possible. But within those margins unit tests are fine. Just introduce them before any scenarios (commit 3297). Reorganizing layers can be easy. Just merge layers for starters! Punt on resplitting them in some new way until you've gotten them to work. This is the wisdom of Refactoring: small steps. What made it hard was not wanting to merge *everything* between layer 30 and 55. The eventual insight was realizing I just need to move those two full-strength transforms and nothing else.
* 3305 - show all available precision in numbersKartik K. Agaram2016-09-081-0/+1
| | | | | | | | | | | | | | | Thanks Ella Couch for pointing out that Mu was lying when debugging small numbers. def main [ local-scope x:number <- copy 1 { x <- divide x, 2 $print x, 10/newline loop # until SIGFPE } ]
* 3293Kartik K. Agaram2016-09-021-1/+4
|
* 3292Kartik K. Agaram2016-09-021-12/+12
|
* 3286Kartik K. Agaram2016-08-311-1/+21
|
* 3285Kartik K. Agaram2016-08-311-0/+1
|
* 3279Kartik K. Agaram2016-08-291-1/+1
| | | | | Stop inlining functions because that will complicate separate compilation. It also simplifies the code without impacting performance.
* 3273Kartik K. Agaram2016-08-281-2/+2
| | | | | | | | | | | Undo 3272. The trouble with creating a new section for constants is that there's no good place to order it since constants can be initialized using globals as well as vice versa. And I don't want to add constraints disallowing either side. Instead, a new plan: always declare constants in the Globals section using 'extern const' rather than just 'const', since otherwise constants implicitly have internal linkage (http://stackoverflow.com/questions/14894698/why-does-extern-const-int-n-not-work-as-expected)
* 3272Kartik K. Agaram2016-08-281-1/+1
| | | | | | Move global constants into their own section since we seem to be having trouble linking in 'extern const' variables when manually cleaving mu.cc into separate compilation units.
* 3267Kartik K. Agaram2016-08-281-2/+0
|
* 3260Kartik K. Agaram2016-08-261-6/+6
| | | | | array length = number of elements array size = in locations
* 3101 - purge .traces/ dir from repo historyKartik K. Agaram2016-07-051-2/+1
| | | | | | | | | | | | | | | | | | | | | I'd been toying with this idea for some time now given how large the repo had been growing. The final straw was noticing that people cloning the repo were having to wait *5 minutes*! That's not good, particularly for a project with 'tiny' in its description. After purging .traces/ clone time drops to 7 seconds in my tests. Major issue: some commits refer to .traces/ but don't really change anything there. That could get confusing :/ Minor issues: a) I've linked inside commits on GitHub like a half-dozen times online or over email. Those links are now liable to eventually break. (I seem to recall GitHub keeps them around as long as they get used at least once every 60 days, or something like that.) b) Numbering of commits is messed up because some commits only had changes to the .traces/ sub-directory.
* 3083Kartik K. Agaram2016-07-011-3/+8
|
* 3027Kartik K. Agaram2016-06-021-2/+2
|