CircuitPython - a Python implementation for teaching coding with microcontrollers https://git.suspectdevices.com/suspect-devices/circuitpython/atom?h=4.1.0-beta.0 2018-08-17T00:40:57+00:00 2018-08-17T00:40:57+00:00 Scott Shawcroft scott@tannewt.org 2018-08-16T01:32:37+00:00 urn:sha1:de5a9d72dcdaacdd5048195cd5bab007f4b2baef This saves code space in builds which use link-time optimization. The optimization drops the untranslated strings and replaces them with a compressed_string_t struct. It can then be decompressed to a c string. Builds without LTO work as well but include both untranslated strings and compressed strings. This work could be expanded to include QSTRs and loaded strings if a compress method is added to C. Its tracked in #531. 2018-08-07T21:58:57+00:00 Scott Shawcroft scott@tannewt.org 2018-07-31T23:53:54+00:00 urn:sha1:933add6cd833bb6ba6682ad2b6eb478871415ff5 2018-07-11T20:45:30+00:00 Dan Halbert halbert@halwitz.org 2018-07-11T20:45:30+00:00 urn:sha1:7c219600a246d8956d0b23ea3f5d125a820e6b6a 2018-07-03T12:45:51+00:00 Scott Shawcroft scott@tannewt.org 2018-06-28T17:43:39+00:00 urn:sha1:cced51cbd23aa732f0243fe555b4427ff46267b4 2018-01-24T18:33:46+00:00 Scott Shawcroft scott.shawcroft@gmail.com 2018-01-24T00:22:05+00:00 urn:sha1:416abe33ed44e44d8f75342731080217e123278b This adapts the allocation process to start from either end of the heap when searching for free space. The default behavior is identical to the existing behavior where it starts with the lowest block and looks higher. Now it can also look from the highest block and lower depending on the long_lived parameter to gc_alloc. As the heap fills, the two sections may overlap. When they overlap, a collect may be triggered in order to keep the long lived section compact. However, free space is always eligable for each type of allocation. By starting from either of the end of the heap we have ability to separate short lived objects from long lived ones. This separation reduces heap fragmentation because long lived objects are easy to densely pack. Most objects are short lived initially but may be made long lived when they are referenced by a type or module. This involves copying the memory and then letting the collect phase free the old portion. QSTR pools and chunks are always long lived because they are never freed. The reallocation, collection and free processes are largely unchanged. They simply also maintain an index to the highest free block as well as the lowest. These indices are used to speed up the allocation search until the next collect. In practice, this change may slightly slow down import statements with the benefit that memory is much less fragmented afterwards. For example, a test import into a 20k heap that leaves ~6k free previously had the largest continuous free space of ~400 bytes. After this change, the largest continuous free space is over 3400 bytes. 2017-11-29T06:01:39+00:00 Damien George damien.p.george@gmail.com 2017-11-29T05:58:27+00:00 urn:sha1:8e323b8fa84277531685985327fb682761abd53d So long as the input qstr identifier is valid (below the maximum number of qstrs) the function will always return a valid pointer. This patch eliminates the "return 0" dead-code. 2017-11-01T02:16:16+00:00 Damien George damien.p.george@gmail.com 2017-11-01T02:16:16+00:00 urn:sha1:487dbdb26748b86cf247600af187437310311145 The technique of using alloca is how dotted import names are composed in mp_import_from and mp_builtin___import__, so use the same technique in the compiler. This puts less pressure on the heap (only the stack is used if the qstr already exists, and if it doesn't exist then the standard qstr block memory is used for the new qstr rather than a separate chunk of the heap) and reduces overall code size. 2017-08-15T01:53:36+00:00 Stefan Naumann me@stefannaumann.de 2017-07-24T16:55:14+00:00 urn:sha1:ace9fb54053c29574bdf81ffacc5ddcf9d4b45d9 It enables all the DEBUG_printf outputs in the py/ source code. 2017-07-31T08:35:40+00:00 Alexander Steffen devel.20.webmeister@spamgourmet.com 2017-06-30T07:22:17+00:00 urn:sha1:55f33240f3d7051d4213629e92437a36f1fac50e There were several different spellings of MicroPython present in comments, when there should be only one. 2016-11-02T12:15:41+00:00 Colin Hogben colin@infinnovation.co.uk 2016-10-31T14:05:56+00:00 urn:sha1:f9b6b37cf65c4f65c4ad461d439fbf624c0f10c1 In both parse.c and qstr.c, an internal chunking allocator tidies up by calling m_renew to shrink an allocated chunk to the size used, and assumes that the chunk will not move. However, when MICROPY_ENABLE_GC is false, m_renew calls the system realloc, which does not guarantee this behaviour. Environments where realloc may return a different pointer include: (1) mbed-os with MBED_HEAP_STATS_ENABLED (which adds a wrapper around malloc & friends; this is where I was hit by the bug); (2) valgrind on linux (how I diagnosed it). The fix is to call m_renew_maybe with allow_move=false.