It's possible for a deep recursion to be all in C instead of
JIT-generated code, in which case the caching code for
`current-continuation-mark' cannot kick in to make the operation
effectively constant time. Bail out (to keep things constant time) if
that happens.
The old implementation could cause deadlock by blocking on a semaphore
while waiting for the original place to run a callback, but a master
GC might be needed (and the blocked place wouldn't get the signal).
Beside fixing that problem, a potential memory leak is fixed in
calling an ffi funcition and having a Racket->C unmarshaling fail.
Also, the GC marking routine for a `place' value didn't reference the
place's underlying `place_obj' value.
The bug is triggered by unsafe flonum operations, a
conversion that tries to make the arguments more unboxable,
and a `lambda' form within an argument to the unsafe
operation.
Closes PR 12587
I now think the problem is likely to be realted to values
that do not fit into a signed 32-bit integer. Check for
the OS version and reject such integers.
The ActiveX part of MysterX is gone. The `ffi/com' re-imeplemtnation
provides only core COM support.
The "mysssink" DLL is still needed, and its source is still
in the tree, but it is downloaded in the same way as other
pre-built DLLs. The DLL no longer needs to be registered with
regsvr32.
The prohbition against `handle-evt' on `handle-evt' is as
document and as originally intended. I'm not sure why it
was allowed.
Existing programs that use `handle-evt' incorrectly
can break. I found and fixed one incorrect use and one
questionable use in the Racket tree (which is a small
minority of the uses of `handle-evt' in the tree).
Extend `define-cstruct' to support #:property specs, which causes
the constructor and C->Racket coercsions to wrap the pointer in
a structure instance with the specified properties. Of course,
the wrapper structure has a `prop:cpointer' property so that the
wrapper can be used transparently as a C pointer.
Add missing tests and documentation for the id`->list', `list->'id,
id`->list*', and `list*->'id bindings created by `define-cstruct'.
This addition triggered several other changes:
* -k for a Mac OS X embedding is now relative to the __PLTSCHEME
segment (which means that executables won't break if you strip
them, for example)
* the command-line no longer has a limited size for Mac OS X
launchers and embedding executables
* Mac OS X GUI and Windows launchers record the creation-time
collection path, unless they are created as "relative" launchers
In particular, allow a pair of a relative-to directory and a base
directory. Paths that syntactically extend the base directory are
recorded as relative to the relative-to directory (which must
syntactically extend the base directory).
The compilation manager now sets the parameter to a pair with
the base directory as the main collection directory, if the source
file's path extends that directory's path.
This generalization solves problems created by cross-module inlining,
where the source location of a procedure in bytecode can now be in a
different file than the enclosing module's file.
Also add a test that checks whether the build directory shows up
in any ".zo", ".dep", or documentation ".html" files.
Closes PR 12549
It looks like my bound for last time was too conservative,
in that I looked for the lowest number that didn't seem
to fail in 10.6. The range of failing values is apparently
not continuous.
I've tightened the bound to match the lowest
number that produces a useful result on my 10.7 machine,
assuming that it works for a continuous range there.
(The new bound is higher than the number previously used as
a lower bound.)
Merge to 5.2.1
Setting the environment variable causes the bytecode compiler to run
the bytecode validator (which is normally applied to input from a
bytecode file) immediately on all of the compiler's own results.
Certain `lambda'-lifting operations can cause information
about the flonumness of a variable to get lost, leading
to a mismatch between the closure's flags and flags on
a variable reference. (The bytecode validator could detect the
bug when loading the broken bytecode. The broken information,
meanwhile, was only used by the JIT.)
For numbers around -67768122973228093, localtime() doesn't return in
10.6.8, while it returns NULL for 10.7.2. Work around the bug by
setting a lower bound that seems to be high enough to avoid the
problem (and that's lower than the lowest value that succeeds, so no
results are lost, at least for now).
Merge to 5.2.1
If a function with a rest arg is called with argv not at the
start of the runstack, then space is allocated for the rest-arg list
on the runstack without clearing the allocated slot. The value in
the slot could be a pointer that wasn't traversed by the most recent
GC, so it could crash a GC during allocation of the rest-arg list.
Also, tweak setup code for a function of no arguments, and improve
comments in the code.
Merge to 5.2.1
The generated code was checking arity after potentially copying
arguments to the start of the runstack (i.e., if the arguments
were not already there). If too few arguments are provided, then
the copy might access past the end of the given array.
The redundant arity check removed in commit f7c506471b
had previously masked this problem. (Or the check wasn't redundant
in that sense, but it's better this way.)
Merge to 5.2.1
The problem is related to marks that should cancel eagerly when
a form passes through many layers of macro expansion, such as in
the sieve stress test for `syntax-rules'.
There's no particular reason that any one format will have all
the information that other formats need, but it conveniently works
for now that HTML info can subsume Latex info.
Certain unsafe operations were allowed to propagate across a
`lambda' boundary (where space safety is known not to be an issue),
which could lead to duplicate uses of a "once used" variable if
the relevant `lambda' is inlined.
Furthermore, `lambda' boundary crossing wasn't detected in the case
that the operation to propagate was propagated through an intermediate
variable without a `lambda' crossing.
Merge to 5.2.1
I'm fairly certain that the change in commit 25e9bd2a190acf861 isn't
right, but I'm having trouble generating tests to demonstrate the
original bug or this correction.
First use of the function was determining a single arity for
the enclosing module, and that arity could trigger warnings
in addition to failures to inline. For example, using `map'
on 3 arguments would trigger incorrect warnings for later
uses of `map' on 2 arguments.
Rename `read-intern-literal' to `datum-intern-literal'.
Interning is needed only in `read-syntax' or `datum->syntax' to
set up the invariants that the bytecode compiler needs for cross-module
optimization. When `read'ing numbers from a data file, meanwhile,
interning slows things down a lot and doesn't seem worthwhile.
Pass a pointer to the thread-local table on entry to JIT-generated
code, instead of having the JIT-generated code call a C function
to get the table. This doesn't seem to improve performance on my
machine, but it generates less code and is probably faster in
some cases.
When a future is blocked on JIT generation, a lightweight closure
is captured, and then the future moves on, the runtime thread would
correctly shift the on-demand JIT argument to the captured copy
of the runstack. However, it would also add 2 to that pointer
to use as the argv array, and the captured runstack is not allocated
to allow interior pointers, so a GC during on-demand JIT could
crash. The solution is to keep an offset alongside the argv pointer
during JITting.
The over-eager transformation could be space-unsafe, and it
could duplicate an unsafe operation whose result is used only
once in a function that eds up being inlined multiple times.
More generally, support a
(define _id (begin 'compiler-hint:cross-module-inline _proc-expr))
hint, which is how the compiler determines that `map', etc., are
candidates for inlining.
Inline only trivial functions, such as `(empty? x)' -> `(null? x)',
to avoid generating too much code.
Bytecode includes a new `inline-variant' form, which records a
version of a function that is suitable for cross-module inlining.
Mostly, the variant let the run-time system to retain a copy
of the bytecode while JITting (and dropping the bytecode of)
the main variant, but it may be different from the main variant
in other ways that make it better for inlining (such a less loop
unrolling).
An unreceived message can have a reference to a master-allocated
value, in which case that value must be marked. This marking
is implemented by embedding a linked link within the message
memory.
This improvement applies to both poll() and select() modes, and it
can reduce scheduling overhead when blocking on many I/O sources
at once.
This mode is not enabled for Windows, however, since Racket doesn't
exactly use select() on Windows.
On Mac OS X, poll() doesn't work right in versions earlier than 10.5.5,
select() is always faster, and large number of sockets will be
better handled via kqueue(). On Linux, poll() is defintely better.
Otherwise, we stick with select() to be conservative.
Applies in the case of simple ports without line counting, etc.
Also, `read-line' keeps track of whether all bytes are ASCII
(which is easy) to shortcut general UTF-8 decoding.
On x86_64, if the scratch-space address fits into 32
bits and the final place for shared code doesn't
fit into a 32-bit address, then the size of the generated
code could change, leading to a JIT buffer overflow.
Merge to 5.2
Fix memory accounting to detect when messages pile up in a
place channel and when shared values (such as the result of
`make-shared-bytes') pile up. Also fix problems where a GC
or free-page purge needs to be triggered.
The implementation causes a minor API change, which is that
a place channel sent multiple times as a message generates
values that are `equal?' but no longer eq?'.
Closes PR 12273
[Do not merge to 5.2]
Reordering `unsafe-vector-ref' past an `unsafe-vector-set!' was
particularly bad. Meanwhile, some non-mutating operations like
`unsafe-mcar' were treated too conservatively.
Merge to 5.2
The bug was that a procedure could be incorrectly marked as
a "leaf" procedure, which could in turn cause the compiler
to keep inlining a very small procedure that calls itself.
Closes PR 12270
Merge to 5.2
