#!/usr/bin/env python3

"""A test case update script.

This script is a utility to update LLVM 'llc' based test cases with new
FileCheck patterns. It can either update all of the tests in the file or
a single test function.
"""

from __future__ import print_function

import argparse
import os  # Used to advertise this file's name ("autogenerated_note").

from UpdateTestChecks import common

# llc is the only llc-like in the LLVM tree but downstream forks can add
# additional ones here if they have them.
LLC_LIKE_TOOLS = [
    "llc",
]


def main():
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument(
        "--llc-binary",
        default=None,
        help='The "llc" binary to use to generate the test case',
    )
    parser.add_argument("--function", help="The function in the test file to update")
    parser.add_argument(
        "--extra_scrub",
        action="store_true",
        help="Always use additional regex to further reduce diffs between various subtargets",
    )
    parser.add_argument(
        "--x86_scrub_sp",
        action="store_true",
        default=True,
        help="Use regex for x86 sp matching to reduce diffs between various subtargets",
    )
    parser.add_argument("--no_x86_scrub_sp", action="store_false", dest="x86_scrub_sp")
    parser.add_argument(
        "--x86_scrub_rip",
        action="store_true",
        default=False,
        help="Use more regex for x86 rip matching to reduce diffs between various subtargets",
    )
    parser.add_argument(
        "--no_x86_scrub_rip", action="store_false", dest="x86_scrub_rip"
    )
    parser.add_argument(
        "--no_x86_scrub_mem_shuffle",
        action="store_true",
        default=False,
        help="Reduce scrubbing shuffles with memory operands",
    )
    parser.add_argument(
        "--tool",
        default=None,
        help="Treat the given tool name as an llc-like tool for which check lines should be generated",
    )
    parser.add_argument(
        "--default-march",
        default=None,
        help="Set a default -march for when neither triple nor arch are found in a RUN line",
    )
    parser.add_argument("tests", nargs="+")
    initial_args = common.parse_commandline_args(parser)

    script_name = os.path.basename(__file__)

    for ti in common.itertests(
        initial_args.tests, parser, script_name="utils/" + script_name
    ):
        triple_in_ir = None
        for l in ti.input_lines:
            m = common.TRIPLE_IR_RE.match(l)
            if m:
                triple_in_ir = m.groups()[0]
                break

        run_list = []
        for l in ti.run_lines:
            if "|" not in l:
                common.warn("Skipping unparsable RUN line: " + l)
                continue

            commands = [cmd.strip() for cmd in l.split("|")]
            assert len(commands) >= 2
            preprocess_cmd = None
            if len(commands) > 2:
                preprocess_cmd = " | ".join(commands[:-2])
            llc_cmd = commands[-2]
            filecheck_cmd = commands[-1]
            llc_tool = llc_cmd.split(" ")[0]

            triple_in_cmd = None
            m = common.TRIPLE_ARG_RE.search(llc_cmd)
            if m:
                triple_in_cmd = m.groups()[0]

            march_in_cmd = ti.args.default_march
            m = common.MARCH_ARG_RE.search(llc_cmd)
            if m:
                march_in_cmd = m.groups()[0]

            m = common.DEBUG_ONLY_ARG_RE.search(llc_cmd)
            if m and m.groups()[0] == "isel":
                from UpdateTestChecks import isel as output_type
            else:
                from UpdateTestChecks import asm as output_type

            common.verify_filecheck_prefixes(filecheck_cmd)

            llc_like_tools = LLC_LIKE_TOOLS[:]
            if ti.args.tool:
                llc_like_tools.append(ti.args.tool)
            if llc_tool not in llc_like_tools:
                common.warn("Skipping non-llc RUN line: " + l)
                continue

            if not filecheck_cmd.startswith("FileCheck "):
                common.warn("Skipping non-FileChecked RUN line: " + l)
                continue

            llc_cmd_args = llc_cmd[len(llc_tool) :].strip()
            llc_cmd_args = llc_cmd_args.replace("< %s", "").replace("%s", "").strip()
            if ti.path.endswith(".mir"):
                llc_cmd_args += " -x mir"
            check_prefixes = common.get_check_prefixes(filecheck_cmd)

            # FIXME: We should use multiple check prefixes to common check lines. For
            # now, we just ignore all but the last.
            run_list.append(
                (
                    check_prefixes,
                    llc_tool,
                    llc_cmd_args,
                    preprocess_cmd,
                    triple_in_cmd,
                    march_in_cmd,
                )
            )

        if ti.path.endswith(".mir"):
            check_indent = "  "
        else:
            check_indent = ""

        ginfo = common.make_asm_generalizer(version=1)
        builder = common.FunctionTestBuilder(
            run_list=run_list,
            flags=type(
                "",
                (object,),
                {
                    "verbose": ti.args.verbose,
                    "filters": ti.args.filters,
                    "function_signature": False,
                    "check_attributes": False,
                    "replace_value_regex": [],
                },
            ),
            scrubber_args=[ti.args],
            path=ti.path,
            ginfo=ginfo,
        )

        for (
            prefixes,
            llc_tool,
            llc_args,
            preprocess_cmd,
            triple_in_cmd,
            march_in_cmd,
        ) in run_list:
            common.debug("Extracted LLC cmd:", llc_tool, llc_args)
            common.debug("Extracted FileCheck prefixes:", str(prefixes))

            raw_tool_output = common.invoke_tool(
                ti.args.llc_binary or llc_tool,
                llc_args,
                ti.path,
                preprocess_cmd,
                verbose=ti.args.verbose,
            )
            triple = triple_in_cmd or triple_in_ir
            if not triple:
                triple = common.get_triple_from_march(march_in_cmd)

            scrubber, function_re = output_type.get_run_handler(triple)
            builder.process_run_line(function_re, scrubber, raw_tool_output, prefixes)
            builder.processed_prefixes(prefixes)

        func_dict = builder.finish_and_get_func_dict()
        global_vars_seen_dict = {}

        is_in_function = False
        is_in_function_start = False
        func_name = None
        prefix_set = set([prefix for p in run_list for prefix in p[0]])
        common.debug("Rewriting FileCheck prefixes:", str(prefix_set))
        output_lines = []

        include_generated_funcs = common.find_arg_in_test(
            ti,
            lambda args: ti.args.include_generated_funcs,
            "--include-generated-funcs",
            True,
        )

        generated_prefixes = []
        if include_generated_funcs:
            # Generate the appropriate checks for each function.  We need to emit
            # these in the order according to the generated output so that CHECK-LABEL
            # works properly.  func_order provides that.

            # We can't predict where various passes might insert functions so we can't
            # be sure the input function order is maintained.  Therefore, first spit
            # out all the source lines.
            common.dump_input_lines(output_lines, ti, prefix_set, ";")

            # Now generate all the checks.
            generated_prefixes = common.add_checks_at_end(
                output_lines,
                run_list,
                builder.func_order(),
                check_indent + ";",
                lambda my_output_lines, prefixes, func: output_type.add_checks(
                    my_output_lines,
                    check_indent + ";",
                    prefixes,
                    func_dict,
                    func,
                    ginfo,
                    global_vars_seen_dict,
                    is_filtered=builder.is_filtered(),
                ),
            )
        else:
            for input_info in ti.iterlines(output_lines):
                input_line = input_info.line
                args = input_info.args
                if is_in_function_start:
                    if input_line == "":
                        continue
                    if input_line.lstrip().startswith(";"):
                        m = common.CHECK_RE.match(input_line)
                        if not m or m.group(1) not in prefix_set:
                            output_lines.append(input_line)
                            continue

                    # Print out the various check lines here.
                    generated_prefixes.extend(
                        output_type.add_checks(
                            output_lines,
                            check_indent + ";",
                            run_list,
                            func_dict,
                            func_name,
                            ginfo,
                            global_vars_seen_dict,
                            is_filtered=builder.is_filtered(),
                        )
                    )
                    is_in_function_start = False

                if is_in_function:
                    if common.should_add_line_to_output(input_line, prefix_set):
                        # This input line of the function body will go as-is into the output.
                        output_lines.append(input_line)
                    else:
                        continue
                    if input_line.strip() == "}":
                        is_in_function = False
                    continue

                # If it's outside a function, it just gets copied to the output.
                output_lines.append(input_line)

                m = common.IR_FUNCTION_RE.match(input_line)
                if not m:
                    continue
                func_name = m.group(1)
                if args.function is not None and func_name != args.function:
                    # When filtering on a specific function, skip all others.
                    continue
                is_in_function = is_in_function_start = True

        if ti.args.gen_unused_prefix_body:
            output_lines.extend(
                ti.get_checks_for_unused_prefixes(run_list, generated_prefixes)
            )

        common.debug("Writing %d lines to %s..." % (len(output_lines), ti.path))
        with open(ti.path, "wb") as f:
            f.writelines(["{}\n".format(l).encode("utf-8") for l in output_lines])


if __name__ == "__main__":
    main()