call the garbage collector now and then

this enables the assembler to translate larger source files without running out of memory.

Author: ThomasWaldmann

esp32_ulp/__main__.py

@@ -1,28 +1,38 @@
 import sys
 
+from .util import garbage_collect
+garbage_collect('before import')
+
 from .assemble import Assembler
 from .link import make_binary
 
 
 def src_to_binary(src):
+ garbage_collect('before assembler init')
  assembler = Assembler()
+ garbage_collect('before assembler call')
  assembler.assemble(src)
+ garbage_collect('before symbols export')
  addrs_syms = assembler.symbols.export()
  for addr, sym in addrs_syms:
  print('%04d %s' % (addr, sym))
 
+ garbage_collect('before fetch')
  text, data, bss_len = assembler.fetch()
+ garbage_collect('before make binary')
  return make_binary(text, data, bss_len)
 
 
 def main(fn):
+ garbage_collect('before read')
  with open(fn) as f:
  src = f.read()
 
  binary = src_to_binary(src)
 
  if fn.endswith('.s') or fn.endswith('.S'):
  fn = fn[:-2]
+ garbage_collect('before write')
  with open(fn + '.ulp', 'wb') as f:
  f.write(binary)
 

esp32_ulp/assemble.py

@@ -4,6 +4,7 @@
 
 from . import opcodes
 from .nocomment import remove_comments
+from .util import garbage_collect
 
 TEXT, DATA, BSS = 'text', 'data', 'bss'
 
@@ -141,6 +142,7 @@ def parse_line(self, line):
 
  def parse(self, text):
  lines = remove_comments(text)
+ garbage_collect('after remove comments')
  parsed = [self.parse_line(line) for line in lines]
  return [p for p in parsed if p is not None]
 
@@ -272,9 +274,12 @@ def assembler_pass(self, lines):
  self.finalize_sections()
 
  def assemble(self, lines):
+ garbage_collect('before pass1')
  self.init(1) # pass 1 is only to get the symbol table right
  self.assembler_pass(lines)
  self.symbols.set_bases(self.compute_bases())
+ garbage_collect('before pass2')
  self.init(2) # now we know all symbols and bases, do the real assembler pass, pass 2
  self.assembler_pass(lines)
+ garbage_collect('after pass2')
 

esp32_ulp/util.py

@@ -0,0 +1,11 @@
+DEBUG = False
+
+import gc
+
+
+def garbage_collect(msg, verbose=DEBUG):
+ free_before = gc.mem_free()
+ gc.collect()
+ free_after = gc.mem_free()
+ if verbose:
+ print("%s: %d --gc--> %d bytes free" % (msg, free_before, free_after))