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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-15 20:38:23 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-15 20:38:23 +0000
commitff6e3c025658a5fa1affd094f220b623e7e1b24b (patch)
tree9faab72d69c92d24e349d184f5869b9796f17e0c /tools/glsl_preproc/statement.py
parentInitial commit. (diff)
downloadlibplacebo-ff6e3c025658a5fa1affd094f220b623e7e1b24b.tar.xz
libplacebo-ff6e3c025658a5fa1affd094f220b623e7e1b24b.zip
Adding upstream version 6.338.2.upstream/6.338.2upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/glsl_preproc/statement.py')
-rw-r--r--tools/glsl_preproc/statement.py301
1 files changed, 301 insertions, 0 deletions
diff --git a/tools/glsl_preproc/statement.py b/tools/glsl_preproc/statement.py
new file mode 100644
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+++ b/tools/glsl_preproc/statement.py
@@ -0,0 +1,301 @@
+import re
+
+from templates import GLSL_BLOCK_TEMPLATE
+from variables import VarSet, slugify
+
+VAR_PATTERN = re.compile(flags=re.VERBOSE, pattern=r'''
+ # long form ${ ... } syntax
+ \${ (?:\s*(?P<type>(?: # optional type prefix
+ ident # identifiers (always dynamic)
+ | (?:(?:const|dynamic)\s+)? # optional const/dynamic modifiers
+ (?:float|u?int) # base type
+ | swizzle # swizzle mask
+ | (?:i|u)?vecType # vector type (for mask)
+ )):)?
+ (?P<expr>[^{}]+)
+ }
+| \$(?P<name>\w+) # reference to captured variable
+| @(?P<var>\w+) # reference to locally defined var
+''')
+
+class FmtSpec(object):
+ def __init__(self, ctype='ident_t', fmtstr='_%hx',
+ wrap_expr=lambda name, expr: expr,
+ fmt_expr=lambda name: name):
+ self.ctype = ctype
+ self.fmtstr = fmtstr
+ self.wrap_expr = wrap_expr
+ self.fmt_expr = fmt_expr
+
+ @staticmethod
+ def wrap_var(type, dynamic=False):
+ if dynamic:
+ return lambda name, expr: f'sh_var_{type}(sh, "{name}", {expr}, true)'
+ else:
+ return lambda name, expr: f'sh_const_{type}(sh, "{name}", {expr})'
+
+ @staticmethod
+ def wrap_fn(fn):
+ return lambda name: f'{fn}({name})'
+
+VAR_TYPES = {
+ # identifiers: get mapped as-is
+ 'ident': FmtSpec(),
+
+ # normal variables: get mapped as shader constants
+ 'int': FmtSpec(wrap_expr=FmtSpec.wrap_var('int')),
+ 'uint': FmtSpec(wrap_expr=FmtSpec.wrap_var('uint')),
+ 'float': FmtSpec(wrap_expr=FmtSpec.wrap_var('float')),
+
+ # constant variables: get printed directly into the source code
+ 'const int': FmtSpec(ctype='int', fmtstr='%d'),
+ 'const uint': FmtSpec(ctype='unsigned', fmtstr='uint(%u)'),
+ 'const float': FmtSpec(ctype='float', fmtstr='float(%f)'),
+
+ # dynamic variables: get loaded as shader variables
+ 'dynamic int': FmtSpec(wrap_expr=FmtSpec.wrap_var('int', dynamic=True)),
+ 'dynamic uint': FmtSpec(wrap_expr=FmtSpec.wrap_var('uint', dynamic=True)),
+ 'dynamic float': FmtSpec(wrap_expr=FmtSpec.wrap_var('float', dynamic=True)),
+
+ # component mask types
+ 'swizzle': FmtSpec(ctype='uint8_t', fmtstr='%s', fmt_expr=FmtSpec.wrap_fn('sh_swizzle')),
+ 'ivecType': FmtSpec(ctype='uint8_t', fmtstr='%s', fmt_expr=FmtSpec.wrap_fn('sh_float_type')),
+ 'uvecType': FmtSpec(ctype='uint8_t', fmtstr='%s', fmt_expr=FmtSpec.wrap_fn('sh_float_type')),
+ 'vecType': FmtSpec(ctype='uint8_t', fmtstr='%s', fmt_expr=FmtSpec.wrap_fn('sh_float_type')),
+}
+
+def stringify(value, strip):
+ end = '\\n"'
+ if strip:
+ end = '"'
+ value = re.sub(r'(?:\/\*[^\*]*\*\/|\/\/[^\n]+|^\s*)', '', value)
+ return '"' + value.replace('\\', '\\\\').replace('"', '\\"') + end
+
+def commentify(value, strip):
+ if strip:
+ return ''
+ return '/*' + value.replace('/*', '[[').replace('*/', ']]') + '*/'
+
+# Represents a statement + its enclosed variables
+class Statement(object):
+ def __init__(self, linenr=0):
+ super().__init__()
+ self.linenr = linenr
+ self.vars = VarSet()
+
+ def add_var(self, ctype, expr, name=None):
+ return self.vars.add_var(ctype, expr, name, self.linenr)
+
+ def render(self):
+ raise NotImplementedError
+
+ @staticmethod
+ def parse(text_orig, **kwargs):
+ raise NotImplementedError
+
+# Represents a single line of GLSL
+class GLSLLine(Statement):
+ class GLSLVar(object): # variable reference
+ def __init__(self, fmt, var):
+ self.fmt = fmt
+ self.var = var
+
+ def __init__(self, text, strip=False, **kwargs):
+ super().__init__(**kwargs)
+ self.refs = []
+ self.strip = strip
+
+ # produce two versions of line, one for printf() and one for append()
+ text = text.rstrip()
+ self.rawstr = stringify(text, strip)
+ self.fmtstr = stringify(re.sub(VAR_PATTERN, self.handle_var, text.replace('%', '%%')), strip)
+
+ def handle_var(self, match):
+ # local @var
+ if match['var']:
+ self.refs.append(match['var'])
+ return '%d'
+
+ # captured $var
+ type = match['type']
+ name = match['name']
+ expr = match['expr'] or name
+ name = name or slugify(expr)
+
+ fmt = VAR_TYPES[type or 'ident']
+ self.refs.append(fmt.fmt_expr(self.add_var(
+ ctype = fmt.ctype,
+ expr = fmt.wrap_expr(name, expr),
+ name = name,
+ )))
+
+ if fmt.ctype == 'ident_t':
+ return commentify(name, self.strip) + fmt.fmtstr
+ else:
+ return fmt.fmtstr
+
+# Represents an entire GLSL block
+class GLSLBlock(Statement):
+ def __init__(self, line):
+ super().__init__(linenr=line.linenr)
+ self.lines = []
+ self.refs = []
+ self.append(line)
+
+ def append(self, line):
+ assert isinstance(line, GLSLLine)
+ self.lines.append(line)
+ self.refs += line.refs
+ self.vars.merge(line.vars)
+
+ def render(self):
+ return GLSL_BLOCK_TEMPLATE.render(block=self)
+
+# Represents a statement which can either take a single line or a block
+class BlockStart(Statement):
+ def __init__(self, multiline=False, **kwargs):
+ super().__init__(**kwargs)
+ self.multiline = multiline
+
+ def add_brace(self, text):
+ if self.multiline:
+ text += ' {'
+ return text
+
+# Represents an @if
+class IfCond(BlockStart):
+ def __init__(self, cond, inner=False, **kwargs):
+ super().__init__(**kwargs)
+ self.cond = cond if inner else self.add_var('bool', expr=cond)
+
+ def render(self):
+ return self.add_brace(f'if ({self.cond})')
+
+# Represents an @else
+class Else(BlockStart):
+ def __init__(self, closing, **kwargs):
+ super().__init__(**kwargs)
+ self.closing = closing
+
+ def render(self):
+ text = '} else' if self.closing else 'else'
+ return self.add_brace(text)
+
+# Represents a normal (integer) @for loop, or an (unsigned 8-bit) bitmask loop
+class ForLoop(BlockStart):
+ def __init__(self, var, op, bound, **kwargs):
+ super().__init__(**kwargs)
+ self.comps = op == ':'
+ self.bound = self.add_var('uint8_t' if self.comps else 'int', expr=bound)
+ self.var = var
+ self.op = op
+
+ def render(self):
+ if self.comps:
+ loopstart = f'uint8_t _mask = {self.bound}, {self.var}'
+ loopcond = f'_mask && ({self.var} = __builtin_ctz(_mask), 1)'
+ loopstep = f'_mask &= ~(1u << {self.var})'
+ else:
+ loopstart = f'int {self.var} = 0'
+ loopcond = f'{self.var} {self.op} {self.bound}'
+ loopstep = f'{self.var}++'
+
+ return self.add_brace(f'for ({loopstart}; {loopcond}; {loopstep})')
+
+# Represents a @switch block
+class Switch(Statement):
+ def __init__(self, expr, **kwargs):
+ super().__init__(**kwargs)
+ self.expr = self.add_var('unsigned', expr=expr)
+
+ def render(self):
+ return f'switch ({self.expr}) {{'
+
+# Represents a @case label
+class Case(Statement):
+ def __init__(self, label, **kwargs):
+ super().__init__(**kwargs)
+ self.label = label
+
+ def render(self):
+ return f'case {self.label}:'
+
+# Represents a @default line
+class Default(Statement):
+ def render(self):
+ return 'default:'
+
+# Represents a @break line
+class Break(Statement):
+ def render(self):
+ return 'break;'
+
+# Represents a single closing brace
+class EndBrace(Statement):
+ def render(self):
+ return '}'
+
+# Shitty regex-based statement parser
+PATTERN_IF = re.compile(flags=re.VERBOSE, pattern=r'''
+@\s*if\s* # '@if'
+(?P<inner>@)? # optional leading @
+\((?P<cond>.+)\)\s* # (condition)
+(?P<multiline>{)?\s* # optional trailing {
+$''')
+
+PATTERN_ELSE = re.compile(flags=re.VERBOSE, pattern=r'''
+@\s*(?P<closing>})?\s* # optional leading }
+else\s* # 'else'
+(?P<multiline>{)?\s* # optional trailing {
+$''')
+
+PATTERN_FOR = re.compile(flags=re.VERBOSE, pattern=r'''
+@\s*for\s+\( # '@for' (
+(?P<var>\w+)\s* # loop variable name
+(?P<op>(?:\<=?|:))(?=[\w\s])\s* # '<', '<=' or ':', followed by \s or \w
+(?P<bound>[^\s].*)\s* # loop boundary expression
+\)\s*(?P<multiline>{)?\s* # ) and optional trailing {
+$''')
+
+PATTERN_SWITCH = re.compile(flags=re.VERBOSE, pattern=r'''
+@\s*switch\s* # '@switch'
+\((?P<expr>.+)\)\s*{ # switch expression
+$''')
+
+PATTERN_CASE = re.compile(flags=re.VERBOSE, pattern=r'''
+@\s*case\s* # '@case'
+(?P<label>[^:]+):? # case label, optionally followed by :
+$''')
+
+PATTERN_BREAK = r'@\s*break;?\s*$'
+PATTERN_DEFAULT = r'@\s*default:?\s*$'
+PATTERN_BRACE = r'@\s*}\s*$'
+
+PARSERS = {
+ PATTERN_IF: lambda r, **kw: IfCond(r['cond'], inner=r['inner'], multiline=r['multiline'], **kw),
+ PATTERN_ELSE: lambda r, **kw: Else(closing=r['closing'], multiline=r['multiline'], **kw),
+ PATTERN_FOR: lambda r, **kw: ForLoop(r['var'], r['op'], r['bound'], multiline=r['multiline'], **kw),
+ PATTERN_SWITCH: lambda r, **kw: Switch(r['expr'], **kw),
+ PATTERN_CASE: lambda r, **kw: Case(r['label'], **kw),
+ PATTERN_BREAK: lambda _, **kw: Break(**kw),
+ PATTERN_DEFAULT: lambda _, **kw: Default(**kw),
+ PATTERN_BRACE: lambda _, **kw: EndBrace(**kw),
+}
+
+def parse_line(text_orig, strip, **kwargs):
+ # skip empty lines
+ text = text_orig.strip()
+ if not text:
+ return None
+ if text.lstrip().startswith('@'):
+ # try parsing as statement
+ for pat, fun in PARSERS.items():
+ if res := re.match(pat, text):
+ return fun(res, **kwargs)
+ # return generic error for unrecognized statements
+ raise SyntaxError('Syntax error in directive: ' + text.lstrip())
+ else:
+ # default to literal GLSL line
+ return GLSLLine(text_orig, strip, **kwargs)
+
+Statement.parse = parse_line