ninjabackend: optimize ninja_quote
Use regular expressions to quickly weed out strings that require quoting
On a QEMU build the time spent in ninja_quote goes from 1.978s to 1.281s,
with str.replace being kicked completely out of the profile.
@@ -114,13 +114,17 @@ rsp_threshold = get_rsp_threshold()
# from, etc.), so it must not be shell quoted.
raw_names = {'DEPFILE_UNQUOTED', 'DESC', 'pool', 'description', 'targetdep'}
+NINJA_QUOTE_BUILD_PAT = re.compile(r"[$ :\n]")
+NINJA_QUOTE_VAR_PAT = re.compile(r"[$ \n]")
+
def ninja_quote(text, is_build_line=False):
if is_build_line:
- qcs = ('$', ' ', ':')
+ quote_re = NINJA_QUOTE_BUILD_PAT
else:
- qcs = ('$', ' ')
- for char in qcs:
- text = text.replace(char, '$' + char)
+ quote_re = NINJA_QUOTE_VAR_PAT
+ # Fast path for when no quoting is necessary
+ if not quote_re.search(text):
+ return text
if '\n' in text:
errmsg = '''Ninja does not support newlines in rules. The content was:
@@ -128,7 +132,7 @@ def ninja_quote(text, is_build_line=False):
Please report this error with a test case to the Meson bug tracker.'''.format(text)
raise MesonException(errmsg)
- return text
+ return quote_re.sub(r'$\g<0>', text)
@unique
class Quoting(Enum):
