Since Chez Scheme now performs the kind of closure conversion that
Racket does --- ensuring that a closure is not allocated if it is
bound to an identifier that is used only in application positions ---
the variant in schemify is not longer run. The hacky macro-based
lifter in the "rumble" layer can also go.
The lifting pass is still preserved in schemify, because it is still
useful to cify. It's not clear whether interpreter mode (which is used
during macro expansion for compile-time code that doesn't cross a
module boundary) is better off with or without schemify's lift, but
it's gone for now.
Reading `1.0e45` produced a different (and less precise) result than
`1e35`. The problem was in the reader's fast path for simple flonum
conversions, where it converts the mantissa and exponent separately
and then combines them. 10^44 is not represented exactly as a flonum,
so there's imprecision when multiplicy it by 10 versus multiplying
1e45 by 1.
Closes#3548
Copy any syntax-original property from the parentheses assodictaed
with a `#%app` made explicit, so that originalness is tracked in
the 'origin property.
New `#%app/no-return` and `#%app/value` functions at the Chez Scheme
level allow schemify to communicate that function calls will not
return or will return a single value. The schmeify pass may have this
information because a Racket-level primitive is declared that way
(such as `error` or `raise-argument-error` for no-return, or most
functions for single-valued) or because single-valuedness is inferred.
There's currently no inference for no-return functions, because those
are relatively rare. An `#%app/value` is used by schemify only for
imported, non-inlined functions, since cp0 can already deal with local
functions and primitives.
There's a start here at adapting the "optimize.rktl" test suite for CS
--- and that effort triggered these improvements plus some other
low-hanging fruit. But a lot more is needed to adapt "optimize.rktl"
and to make some additional optimizations happen.
Avoid a global table to register structure procedures, and instead use
a wrapper procedure. At the same time, adjust schemify to more
agressively inline structure operations, which can avoid a significant
performance penalty for local structure types.
Closes#3535
A procedures that is a value for a structure-type property was not
always inspected correctly. For example, if such a procedure was the
only one to mutate a module variable, then the variable might not be
detected as mutable.
Use data instead of code to shrink ".zo" sizes by 10-30%.
When Racket code contains a literal that cannot be serialized directly
by Chez Scheme (such as a keyword or an immutable string that should
be datum-interned), the old approach was to generate Scheme code to
construct the literal through a lifted `let` binding. To handle paths
associated with procedures, however, Chez Scheme's `fasl-write` had
been extended to allow arbitrary values to be intercepted during fasl
and passed back in to `fasl-read`. Using that strategy for all Racket
literals simplifies the implementation and reduces compiled code. It
also makes closures smaller, while increases the number of
relocations. DrRacket's foorprint shrinks by about 1%, but the main
affect is on disk space for a Racket installation.
Finally give in and add an option to compile a module as unsafe. This
was going to be easy, since the option already exists at the linklet
level, but it turns out that a lot of plumbing was needed to propagate
the argument, and even more to preserve unsafety with cross-module
inlining.
Macros can effectively conditoinalize their expansion in unsafe mode
by generating the pattern
(if (variable-reference-from-unsafe? (#%variable-reference))
<unsafe variant>
<safe variant>)
The compiler will only keep one of the two variants, because it
promises to optimize `(variable-reference-from-unsafe?
(#%variable-reference))` to a literal boolean. The expander will still
expand both variants, however, so avoid putting code in both variants
that itself can have safety variants.
Streamline rktio byte-result copying (main improvement), use fixnum
arithmetic more consistently (minor improvement), and change
`in-bytes`, etc., to avoid some checks in unsafe mode (intermediate
improvement).
When bytes within a Windows path cannot be converted using
`bytes->string/locale` (i.e., when the bytes do not fit a UTF-8
encoding), then leave the bytes alone, instead of triggering a failure
from `bytes->string/locale`.
Fixing this bug uncovered others: `string-locale-downcase` did not
work on an empty byte string on a little-endian machine, and
`in-bytes` and similar reported range errors in terms of "vectors".
Fix mishandling of an expanded `if` where the test position is a
syntax object. The expander's compiler pass from expanded objects to
linkets knows that the syntax object isn't useful, but it tried to be
helpful by preserving the syntax object's content as quoted --- and
that content turns out not to be available, so the syntax object was
replaced by #f, instead.
Closes#3436
Rename definitions that are not exported and that are not used as
inferred function names. The rename is based on a hash of the
right-hand side, instead of being just the position of the definition
in the module, and that should help further reduce diffs in schemified
output after small changes to the source.
Some text-editing tools on Windows include a BOM character (encoded)
at the start of a file that is intended as UTF-8. The general
recommendation for UTF-8 is to *not* include a BOM --- but, well,
Windows. When a BOM is there, meanwhile, the recommendation is to
preserve it in the stream, so always discarding an initial BOM at the
file-port level is not a good idea. A new file mode would make sense,
but distinctions like 'text and 'binary mode have turned out to be
best avoided.
Although I'm not sure it's really a good idea, treating a BOM
character as whitespace in the reader (at least in comment positions)
is an easy way around the problem for text files that are intended as
programs.
Closes#1114
An optimization pass used mostly for inlining did not reqcognize
`quote`, and it could replace a quoted name with a constant-propagated
value.
Closes#3339
The top-level makefile now builds Racket CS as `racket` by default.
Use `racket bc` to build Racket BC as `racket`. Use `make both` to
build both CS and BC (the latter with the `bc` suffix) overlayed in a
single build. By using `make both` insted of `make cs` plus `make bc`,
you can avoid redundant package downloads and documentation rendering.
To build Racket BC as `racket`, use `racket bc RACKETBC_SUFFIX=`, but
you must consistently use `RACKETBC_SUFFIX=` with `make` every time.
Also, schemified "thread", "io", "regexp", "schemify", and "expander"
layers are checked in. Overall, building Racket CS no longer requires
first building Racket BC.
