A `struct-copy` form can generates a call for a constructor that
includes a sequence of `unsafe-struct-ref` arguments. Each
`unsafe-struct-ref` must still check for a chaperone. Make the JIT
recognize that pattern an turn it into a single test instead of
one test per `unsafe-struct-ref`.
http-proxy/ contains a suite of almost useful (but mostly useless) servers.
These can be used to test http-client, and url.rkt
git proxy is not tested yet -- I really wouldn’t know how
Make the optimizer recognize and track `make-struct-property-type`
values, and use that information to recognize `make-struct-type`
calls that will defnitely succeed because a property that hs no
guard is given a value in the list of properties.
Combined with the change to require-keyword expansion, this
change allows the optimizer to inline `f` in
(define (g y)
(f #:x y))
(define (f #:x x)
(list x))
because the `make-struct-type` that appears between `g` and `f`
is determined to have no side-effect that would prevent `f` from
having its expected value.
When a module defines and exports an identifier at two phases,
and when another module imports both of them at the same phase,
an error was not reported as it should have been.
Some expressions are omittable only when the arguments have certain types.
In this case the application is marked with APPN_FLAG_OMITTABLE instead of relaying on the flags of the primitive.
The optimizer can't use this flag to move the expression inside a lamba or across a potential continuation capture, unlike other omittable expressions. They can be moved
only in more restricted conditions.
For example, in this program
#lang racket/base
(define n 10000)
(define m 10000)
(time
(define xs (build-list n (lambda (x) 0)))
(length xs)
(define ws (list->vector xs)) ; <-- omittable
(for ([i (in-range m)])
(vector-ref ws 0))) ; <-- ws is used once
If the optimizer moves the expression in the definition of ws inside the recursive
lambda that is created by the for, then the code is equivalent to:
#lang racket/base
(define n 10000)
(define m 10000)
(time
(define xs (build-list n (lambda (x) 0)))
(length xs)
(for ([i (in-range m)])
(vector-ref (list->vector xs) 0))) ; <-- moved here
And the new code is O(n*m) instead of O(n+m). This example is a minimized version
of the function kde from the plot package, where n=m and the bug changed the run
time from linear to quadratic.
The application of some procedures are omittables when the arguments have
certain properties. Check the arity of the procedure before marking the application as omittable.
The only case that appears to be relevant is the expression (-).
The relevant predicates are almost disjoint. The superposition
is solved with predicate_implies and predicate_implies_not.
This is also valid considering the equivalence classes modulo
eqv? and equal?. So if the optimizer knows that two expressions
X and Y have different relevant types, then it can reduce
(equal? X Y) ==> (begin X Y #f).
Changes signatures in `syntax/modcode` to accept `path-string?` arguments
instead of `path?`.
Before, the docs listed `path-string?` but the contracts used `path?`.
Now they agree.
Allow a `struct` form to be recognized when it provides
a number as the 8th argument to `make-struct-type`. In
particular, that change allows the construction of
optional-keyword functions to be recognized as a
purely functional operation.
Also, allow the optimizer to use information about imports
when deciding whether a module-level form is functional.
It's ok to use that information, because the validator has
it, too.
This combination of changes allows something like
(define (f #:optional [x #f])
(later))
(define (later) ....)
to compile to a reference to `later` wihout a check.
Due to an obvious problem in the setup, the letrec-check pass wasn't
running an intended dead-code pruning pass. Correcting the problem
cuases one test in "optimize.rktl" to change, because the letrec-check
pass can see more in one case than thanother.
(Problem discovered by accidentally fixing the setup in a Racket
branch based on "linklets".)
Along with the `PLT_COMPILED_FILE_CHECK` environment variable, allows
the timestamp check to be disabled when deciding whether to use a
compiled bytecode file.
In accomodating this change, `raco make` and `raco setup` in all modes
check whether the SHA1 hash of a module source matches the one
recorded in its ".dep" file, even if the timestamp on the bytecode
file is newer. (If the compile-file check mode is 'exists, the
timestamp is completely ignored.)
1. Changed the API documentation for scheme_make_hash_tree, adding primitives for:
* SCHEME_hashtr_eq
* SCHEME_hashtr_equal
* SCHEME_hashtr_eqv
2. Changed direct uses of scheme_make_hash_tree to use these enumed values.
3. Fixed bugs in documentation
4. Defaults to racket/interactive (and racket/gui/interactive) if there is nothing in the config file
Now accepts any whitespace, not just spaces, ignores both leading and
trailing whitespace, and accepts multiple whitespace characters
separating subterms.
After refactoring the test for the inferred types of some procedures that
use vector?/bytes?/string?/list? it was easier to spot the missing information.
Note that in the documentation, some arguments like the position in
(vector-ref <vector> <position>)
are documented as exact-nonnegative-integer? but due to the implementation
details they are actually in a subset of fixnum?s.
When `read` parses a literal hash table, it inserts an placeholder
just in case it's needed for cycles. The `unsafe-immutable-hash-...`
operations in some cases did not detect and remove the placeholder.
Closes#1376
Merge to v6.6
The namespace returned by `variable-reference->namespace` (or
`namespace-anchor->namespace`) may be used via `eval` to define new
bindings, so enable top-level binding support for the namespace.
for example, make the optimizer convert something like
(struct a (x))
(lambda (v) (if (a? v) (a-x v) #f))
to
(struct a (x))
(lambda (v) (if (a? v) (unsafe-struct-ref v 0) #f))
The optimizer change in e887fa56d1 recognized struct declarations that
involved only whitelisted properties to guarantee that constructor
properties are preserved --- while `prop:chaperone-unsafe-undefined`
can affect the constructor, and other properties might imply that one.
But the optimizer's transformer aren't actually invalidated by
`prop:chaperone-unsafe-undefined`; the JIT's assumptions are affected,
but that's handled in a different way. So, remove the whitelist and
allow any property list.
This change permits EH patterns like (~once <nullable>), because the
match will happen at most once, so there is no danger of divergence.
Thanks to Alex Knauth for pointing out this special case.
Merge to release branch.
The optimizer tries to reduce the `if` assuming that the result will be used.
In case it later detects that the result will be ignored, it can try to
apply some additional reductions to the branches and to the whole expression.
This function exposes the fast subset operation that is built in for
immutable hash tables (and used by the set-of-scopes implementation).
Also, make the space optimization implicit for `eq?`-based hash tables
that contain only #t values (instead of explicit and only available
internally). It turns out to be easy and efficient to make the
representation automatic, because the HAMT implementation can support
a mixture of nodes with some containing explicit values and some
containing implicit #t values.
Now with-disappeared-uses surrounds its body with let, so it can contain
multiple body expressions. The record-disappeared-use function is like
record-disappeared-uses but for a single identifier.
The `#%linklet` module is intended to eventually provide
a simplified compiler for the core Racket language. For
now, it provides minimal hooks for bootstrapping an
expander implementation.
When the properties argument for `make-struct-type` is non-empty,
then we cant; guarantee that `make-struct-type` succeeds, but
if it does, then we can still know that the result is a structure
type and (as long as `prop:chaperone-unsafe-undefined` is not
involved) the properties don't affect the constructor, predicate,
selector, or mutators.
The resolve-module-path-* functions effectively already had a default argument,
which is #f, this allows you to just directly call it with one argument.
This fixes an immediate problem, but the macro expander should have
complained about an unbound `maybe` at phase 2. (A new implementation
of the macro expander detected the unbound `maybe`.)
In (~and p1 p2), a failure in p2 now always dominates a failure in p1.
Consequently, if a pattern succeeds, its failures don't matter.
Add {pat,hpat,action}:ord wrappers, ord prframes. Apply ordering to
main pattern and side clauses. Add better progress analysis to
eliminate order wrapping.
When an array value is provided, make sure that it's an array
with at least the expected length (or longer) and same element
layout. That's weaker than checking that the array elements have
the right type, because an `eq?` check at the ctype layer seems
too strong, and the ctype API doesn't provide enough information
for a more flexible equality.
Avoid creating a result that is intended as a module path but
has elements that are not syntactically allowed, such as a "."
in a collection-path element.
A phase shift was mising on `begin-for-syntax`es introduced by
`syntax-local-lift-module-end-declaration`, which is in turn
used to implement` module+`, so `module+` didn't work under
two or more `begin-for-syntaxes`.
Closes#1312
Syntax objects generally make sense as properties in other syntax
objects, but they require special care when marshaling to bytecode
(as syntax objects do in general). To make that special handling
possible and reliable, constrain the shape of allowed values.
The name `path-extension` created a conflict for an existing
registered package, so it should not have been added to
`racket/path`.
Also, `path-get-extension` was intended to work on a path
that is syntactically a directory, so fix and test that.
Change the one expansion mode as far as I can tell) that disables
lifts so that lifts are now allowed, which means that
`(syntax-transforming?)` implies `(syntax-transforming--with-lifts?)`.
The old documentation incorrectly characterized when lifts
were allowed. Ryan noticed the documentation problem, and that
observation led to this simplication.
This is a partial solution to the ~and problem, only for side clauses.
In (~and p1 p2 p3), one often wants errors in p2 to take precedence over
errors in p1, and likewise for p3 over p2. One solution is ~commit, but
that prevents backtracking. Another is ~post, but then two ~post wrappers
are needed around p3. Also, it doesn't make sense to compare progress of
the third #:with clause from stxclass A to the second #:with clause of
stxclass B and say third beats second.
So, generalize 'post to (post group index); post frames are comparable to
each other only if group is the same, then compared by index. (Post still
beats CAR and CDR.) Each set of side clauses shares a group.
For simplicity of code generation for now, use gensyms to identify groups.
A `#:name` identifier picks the name that is bound to static
information about a structure type. An `#:extra-name` identifier
specifies an additional name to be bound to the information.
This pair of options is analogous to `#:constructor-name`
and `#:extra-constructor-name`.
Based on Jen Axel's suggestion and implementation.
Closes#1309
Provide a cleaned-up set up path-extension functions. In contrast
to `path-{add,replace}-suffix` and `filename-extension`, a dot
at the beginning of a path element is not treated as an extension
separator. Also, `path-extension` returns an extension including
its separator, which is more consistent with other extension
functions.
The new `path-has-extension?` function replaces many uses of
regexp matching in the base collections.
Closes#1307
Adjusts the docs, but a future replacement (possibly with a new name
to avoid compatibility issues) should behave like the old docs,
instead.
Closes#1292
restricted through `get-info`, which prunes the environment
variable set before it loads the "info.rkt" file. All
environment variables are pruned except those listed in
`PLT_INFO_ALLOW_VARS` (separated by semicolons).
Related to emina/rosette#17.
Add a hook to `raco setup` to make copies of installed executables,
where the copies start with the configuration or addon directory
of creation time, instead of the default installation or user-specific
path.
Although the same effect can be achived by setting environment
variables such as PLTADDONDIR, tethered executables can be easier
to work with and compose better with other programs.
See also #1206 for some discussion, although this change does
not exactly address the original idea there.
Reduce (unbox (box x)) => x
Extend the reductions for cXr to the unsafe versions, for
example reduce (unsafe-car (cons x y)) => x
Check and save types in unsafe operations
Pass a string to the handler to describe the problem.
Also, fix minor issues (GC registration, contracts and `history`
in docs) and make `pregexp`, etc., report compilation errors as
`pregexp`, etc.
Allow `system-type` on non-Windows platforms to run `uname` to get
machine information, even in a sandbox or other contexts with a
limiting secutiry guard.
Check that it works to apply a continuation that shares with
an enclosing continuation, where a runstack overflow happens
between the continuations.
Closes PR 15281
While expanding a module, the root of module-relative references is a
fresh notion of "this module".
After expansion, "this module" is shifted to "an expanded module",
which is a global constant (for top-level modules). When an expanded
module is re-expanded, "an expanded module" is shifted to a fresh
"this module" during re-expansion, and so on.
One problem with this approach is that the shift from "this module" to
"an expanded module" isn't applied to syntax properties --- but
there's some extra trickery to make it work out by mutating "this
module" to make it look like "an expanded module".
Submodule expansion introduces an intermediate "parent of this module"
that wasn't currently covered by the extra trickery, so fix that.
`->i` already supports method contracts (for use wihin `object-contract`,
whose `->i` support is tested, but undocumented), which would make `->im`
possible.
Unfortunately, that support is very incomplete, missing support for using
`this` in contracts, making this `->im` (or the undocumented `->i` +
`object-contract` combo) basically useless.
Once/if that is added, then this commit would enable `->im`. Until then,
it's mostly useful for future reference (hence will be reverted).
In the meantime, it's possible to use `->i` within class/object contracts
with an explicit `this` argument, so nothing critical is lost, just a tiny
shortcut.
Previously, on the example, the function was not anonymous, so no
`tempN' would appear on the error message.
The fixed example makes use of `flat-named-contract' on an anonymous
function, which resembles the snippet above it and demonstrates the
purpose of `flat-named-contract' better.
Repair a mismatch between `syntax-local-lift-expression` and the
way that `compile` tries to avoid creating bindings while
compiling a top-level `define` form.
Closes#1284 and #1282
Some functions were passing when they shouldn't have, only to fail when
the function is called.
Technically not backwards compatible, but should only affect functions
that were never called.
A syntax property is added as preserved or not. For backward
compatibility, the default for a 'paren-shape key is preserved, and
any other key's default is non-preserved.
Cross-module inlining that pulls a variable reference across a
module boundary imposes a more struct requirement that run-time
"constant" detection is consistent with the optimizer's view of
"constant" within a module. So, make sure they're the same.
Sometimes the optimizer removes all the references to a variable but it
doesn't detect that the variable is unused, so it keeps the definition.
Later, the sfs detects the unused variable so it marks it, but it doesn't
remove the let form.
Using `syntax` to capture local binding information in the current
phase doesn't work with the set-of-scopes expander. Although the
example could be adjust to use `(quote-syntax car #:local)`, it
seems like too much detail at that point in the explanation.
Formerly, cross-module inlining would not work for a function like
(define (f x)
(if .... .... (slow x)))
unless `slow` was also inlined into `f`. This commit changes
cross-module inlining so that it allows a call to `f` to be replaced
with an expression that references other module-level bindings (that
are not primitives), such as `slow`.
Adjusting the inlining rules can always make some program worse. In
this case, a hueristic about whether to export an optimized or
unoptimized variant of a fnuciton for inlining tends to collide with
the adjusted inlining rule, so this commit tweaks that heuristic, too.
Enable the optimizer to figure to figure out that a loop
argument is always a real number, for example, in much the
same way that it can detect fixnums and flonums for unboxing.
Unboxing information was only needed at the resolve level,
but `real?` information is useful only to the optimizer, so
the generalization enables the optimizer to reach
approximations of type information earlier (e.g., among
a subset of a function's arguments).
Simplify `(wcm <k1> <v1> (wcm <k1> <v2> <e>))` to
`(begin <v1> (wcm <k1> <v2> <e>))` for a simple enough <k1>.
A variable simple enough, so this is useful for improving
errortrace output.
Compute an `equal?` hash code for `read`able values that
is a constant, at least for a given version of Racket. Only
(interned) symbols failed to have that property before.
An `XFORM_NONGCING_NONALIASING` function doesn't trigger a GC, and
when it is given an argument that is an address of a local variable,
it fills in that address and doesn't leak it. This annotation allows
the xform transformation (to support precise GC) avoid some work for
some hash-iteration functions.
With the old representation of local variables, optimize_info_lookup
had to search the stack for the frame with the information about the
variable. This was complicated so it has many flags to be used in
different situations and extract different kind of information.
With the new representation this process is easier, so it's possible
to split the function into a few smaller functions with an easier
control flow.
In particular, this is useful to avoid marking a variable as used
inside a lambda when the reference in immediately reduced to a
constant using the type information.
The iterator saves the return points in a list. For small immutable hashes,
encode the values in the list in the bits of a fixnum to avoid allocations.
Expose tagged allocation and a function that interprets a description
of tagged shapes. As a furst cut, the description can only specify
constant offsets for pointers within the object, but future extensions
are possible.
When a chaperone-wrapped function leads to a slow-path tail
call, the continuation-mark depth can be made too deep when
resolving the slow tail call.
Closes#1265
Reduce
(eq? v v) ==> #t
(if t v v) ==> (begin t v)
(if v v #f) ==> v
when v is a local or a top level variable.
Previously, the last two reductions were used only
with local variables.
Also, move the (if x #t #f) ==> (not x) reduction
after branch optimization.
When a key is removed at a level that other only has a collision
table, the HAMT representation was not adjusted properly by
eliminating the layer. As aresult, table comparison via
`equal?` could fail. The problem could show up with hash tables
used to represent scope sets, where an internal "subset?" test
could fail and produce an incorrect binding resolution.