loki.frontend.preprocessing

Preprocessing utilities for frontends.

Module Attributes

sanitize_registry

The frontend sanitization registry dict holds workaround rules for Fortran features that cause bugs and failures in frontends.

Functions

preprocess_cpp(source[, filepath, includes, ...])	Invoke an external C-preprocessor to sanitize input files.
reinsert_contiguous(ir, pp_info)	Reinsert the CONTIGUOUS marker into declaration variables.
reinsert_convert_endian(ir, pp_info)	Reinsert the CONVERT='BIG_ENDIAN' or CONVERT='LITTLE_ENDIAN' arguments into calls to OPEN.
reinsert_open_newunit(ir, pp_info)	Reinsert the NEWUNIT=.
sanitize_input(source, frontend)	Apply internal regex-based sanitisation rules to filter out known frontend incompatibilities.

Classes

PPRule(match, replace[, postprocess])

A preprocessing rule that defines and applies a source replacement and collects associated meta-data.

preprocess_cpp(source, filepath=None, includes=None, defines=None)

Invoke an external C-preprocessor to sanitize input files.

Note that the global option LOKI_CPP_DUMP_FILES will cause the intermediate preprocessed source to be written to a temporary file in LOKI_TMP_DIR.

Parameters:

• source (str) – Source string to preprocess via pcpp

• filepath (str or pathlib.Path) – Optional filepath name, which will be used to derive the filename should intermediate file dumping be enabled via the global config.

• includes ((list of) str) – Include paths for the C-preprocessor.

• defines ((list of) str) – Symbol definitions to add to the C-preprocessor.

sanitize_input(source, frontend)

Apply internal regex-based sanitisation rules to filter out known frontend incompatibilities.

Note that this will create a record of all things stripped (pp_info), which will be used to re-insert the dropped source info when converting the parsed AST to our IR.

The sanitize_registry (see below) holds pre-defined rules for each frontend.

sanitize_registry = {Frontend.OMNI: {}, Frontend.OFP: {'CONTIGUOUS': <loki.frontend.preprocessing.PPRule object>, 'FYPP ANNOTATIONS': <loki.frontend.preprocessing.PPRule object>, 'IBM_DIRECTIVES': <loki.frontend.preprocessing.PPRule object>}, Frontend.FP: {'CONVERT_ENDIAN': <loki.frontend.preprocessing.PPRule object>, 'FYPP ANNOTATIONS': <loki.frontend.preprocessing.PPRule object>, 'IBM_DIRECTIVES': <loki.frontend.preprocessing.PPRule object>, 'INTEGER_PP_DIRECTIVES': <loki.frontend.preprocessing.PPRule object>, 'OPEN_NEWUNIT': <loki.frontend.preprocessing.PPRule object>, 'STRING_PP_DIRECTIVES': <loki.frontend.preprocessing.PPRule object>}, Frontend.REGEX: {'FYPP ANNOTATIONS': <loki.frontend.preprocessing.PPRule object>}}

The frontend sanitization registry dict holds workaround rules for Fortran features that cause bugs and failures in frontends. It’s mostly a regex expression that removes certains strings and stores them, so that they can be re-inserted into the IR by a callback.

class PPRule(match, replace, postprocess=None)

Bases: object

A preprocessing rule that defines and applies a source replacement and collects associated meta-data.

reset()

filter(line, lineno)

Filter a source line by matching the given rule and storing meta-content.

property info

Meta-information that will be dumped alongside preprocessed source files to re-insert information into a fully parsed IR tree.

postprocess(ir, info)