Remove the exception and cleanup checkers

Now that gdb is transitioning away from cleanups, there is no reason
to keep the cleanup and exception checker scripts around.  This patch
removes them.

gdb/ChangeLog
2019-01-05  Tom Tromey  <tom@tromey.com>

	* contrib/cleanup_check.py: Remove.
	* contrib/gcc-with-excheck: Remove.
	* contrib/exsummary.py: Remove.
	* contrib/excheck.py: Remove.

1 files changed, 0 insertions, 296 deletions

diff --git a/gdb/contrib/excheck.py b/gdb/contrib/excheck.py
deleted file mode 100644
index 4d53f0581fd..00000000000
--- a/gdb/contrib/excheck.py
+++ /dev/null
@@ -1,296 +0,0 @@
-#   Copyright 2011-2019 Free Software Foundation, Inc.
-#
-#   This is free software: you can redistribute it and/or modify it
-#   under the terms of the GNU General Public License as published by
-#   the Free Software Foundation, either version 3 of the License, or
-#   (at your option) any later version.
-#
-#   This program is distributed in the hope that it will be useful, but
-#   WITHOUT ANY WARRANTY; without even the implied warranty of
-#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-#   General Public License for more details.
-#
-#   You should have received a copy of the GNU General Public License
-#   along with this program.  If not, see
-#   <http://www.gnu.org/licenses/>.
-
-# This is a GCC plugin that computes some exception-handling data for
-# gdb.  This data can then be summarized and checked by the
-# exsummary.py script.
-
-# To use:
-# * First, install the GCC Python plugin.  See
-#   https://fedorahosted.org/gcc-python-plugin/
-# * export PYTHON_PLUGIN=/full/path/to/plugin/directory
-#   This should be the directory holding "python.so".
-# * cd build/gdb; make mostlyclean
-# * make CC=.../gcc-with-excheck
-#   This will write a number of .py files in the build directory.
-# * python .../exsummary.py
-#   This will show the violations.
-
-import gcc
-import gccutils
-import sys
-
-# Where our output goes.
-output_file = None
-
-# Cleanup functions require special treatment, because they take a
-# function argument, but in theory the function must be nothrow.
-cleanup_functions = {
-    'make_cleanup': 1,
-    'make_cleanup_dtor': 1,
-    'make_final_cleanup': 1,
-    'make_my_cleanup2': 1,
-    'make_my_cleanup': 1
-}
-
-# Functions which may throw but which we want to ignore.
-ignore_functions = {
-    # This one is super special.
-    'exceptions_state_mc': 1,
-    # gdb generally pretends that internal_error cannot throw, even
-    # though it can.
-    'internal_error': 1,
-    # do_cleanups and friends are supposedly nothrow but we don't want
-    # to run afoul of the indirect function call logic.
-    'do_cleanups': 1,
-    'do_final_cleanups': 1
-}
-
-# Functions which take a function argument, but which are not
-# interesting, usually because the argument is not called in the
-# current context.
-non_passthrough_functions = {
-    'signal': 1,
-    'add_internal_function': 1
-}
-
-# Return True if the type is from Python.
-def type_is_pythonic(t):
-    if isinstance(t, gcc.ArrayType):
-        t = t.type
-    if not isinstance(t, gcc.RecordType):
-        return False
-    # Hack.
-    return str(t).find('struct Py') == 0
-
-# Examine all the fields of a struct.  We don't currently need any
-# sort of recursion, so this is simple for now.
-def examine_struct_fields(initializer):
-    global output_file
-    for idx2, value2 in initializer.elements:
-        if isinstance(idx2, gcc.Declaration):
-            if isinstance(value2, gcc.AddrExpr):
-                value2 = value2.operand
-                if isinstance(value2, gcc.FunctionDecl):
-                    output_file.write("declare_nothrow(%s)\n"
-                                      % repr(str(value2.name)))
-
-# Examine all global variables looking for pointers to functions in
-# structures whose types were defined by Python.
-def examine_globals():
-    global output_file
-    vars = gcc.get_variables()
-    for var in vars:
-        if not isinstance(var.decl, gcc.VarDecl):
-            continue
-        output_file.write("################\n")
-        output_file.write("# Analysis for %s\n" % var.decl.name)
-        if not var.decl.initial:
-            continue
-        if not type_is_pythonic(var.decl.type):
-            continue
-
-        if isinstance(var.decl.type, gcc.ArrayType):
-            for idx, value in var.decl.initial.elements:
-                examine_struct_fields(value)
-        else:
-            gccutils.check_isinstance(var.decl.type, gcc.RecordType)
-            examine_struct_fields(var.decl.initial)
-
-# Called at the end of compilation to write out some data derived from
-# globals and to close the output.
-def close_output(*args):
-    global output_file
-    examine_globals()
-    output_file.close()
-
-# The pass which derives some exception-checking information.  We take
-# a two-step approach: first we get a call graph from the compiler.
-# This is emitted by the plugin as Python code.  Then, we run a second
-# program that reads all the generated Python and uses it to get a
-# global view of exception routes in gdb.
-class GdbExceptionChecker(gcc.GimplePass):
-    def __init__(self, output_file):
-        gcc.GimplePass.__init__(self, 'gdb_exception_checker')
-        self.output_file = output_file
-
-    def log(self, obj):
-        self.output_file.write("# %s\n" % str(obj))
-
-    # Return true if FN is a call to a method on a Python object.
-    # We know these cannot throw in the gdb sense.
-    def fn_is_python_ignorable(self, fn):
-        if not isinstance(fn, gcc.SsaName):
-            return False
-        stmt = fn.def_stmt
-        if not isinstance(stmt, gcc.GimpleAssign):
-            return False
-        if stmt.exprcode is not gcc.ComponentRef:
-            return False
-        rhs = stmt.rhs[0]
-        if not isinstance(rhs, gcc.ComponentRef):
-            return False
-        if not isinstance(rhs.field, gcc.FieldDecl):
-            return False
-        return rhs.field.name == 'tp_dealloc' or rhs.field.name == 'tp_free'
-
-    # Decode a function call and write something to the output.
-    # THIS_FUN is the enclosing function that we are processing.
-    # FNDECL is the call to process; it might not actually be a DECL
-    # node.
-    # LOC is the location of the call.
-    def handle_one_fndecl(self, this_fun, fndecl, loc):
-        callee_name = ''
-        if isinstance(fndecl, gcc.AddrExpr):
-            fndecl = fndecl.operand
-        if isinstance(fndecl, gcc.FunctionDecl):
-            # Ordinary call to a named function.
-            callee_name = str(fndecl.name)
-            self.output_file.write("function_call(%s, %s, %s)\n"
-                                   % (repr(callee_name),
-                                      repr(this_fun.decl.name),
-                                      repr(str(loc))))
-        elif self.fn_is_python_ignorable(fndecl):
-            # Call to tp_dealloc.
-            pass
-        elif (isinstance(fndecl, gcc.SsaName)
-              and isinstance(fndecl.var, gcc.ParmDecl)):
-            # We can ignore an indirect call via a parameter to the
-            # current function, because this is handled via the rule
-            # for passthrough functions.
-            pass
-        else:
-            # Any other indirect call.
-            self.output_file.write("has_indirect_call(%s, %s)\n"
-                                   % (repr(this_fun.decl.name),
-                                      repr(str(loc))))
-        return callee_name
-
-    # This does most of the work for examine_one_bb.
-    # THIS_FUN is the enclosing function.
-    # BB is the basic block to process.
-    # Returns True if this block is the header of a TRY_CATCH, False
-    # otherwise.
-    def examine_one_bb_inner(self, this_fun, bb):
-        if not bb.gimple:
-            return False
-        try_catch = False
-        for stmt in bb.gimple:
-            loc = stmt.loc
-            if not loc:
-                loc = this_fun.decl.location
-            if not isinstance(stmt, gcc.GimpleCall):
-                continue
-            callee_name = self.handle_one_fndecl(this_fun, stmt.fn, loc)
-
-            if callee_name == 'exceptions_state_mc_action_iter':
-                try_catch = True
-
-            global non_passthrough_functions
-            if callee_name in non_passthrough_functions:
-                continue
-
-            # We have to specially handle calls where an argument to
-            # the call is itself a function, e.g., qsort.  In general
-            # we model these as "passthrough" -- we assume that in
-            # addition to the call the qsort there is also a call to
-            # the argument function.
-            for arg in stmt.args:
-                # We are only interested in arguments which are functions.
-                t = arg.type
-                if isinstance(t, gcc.PointerType):
-                    t = t.dereference
-                if not isinstance(t, gcc.FunctionType):
-                    continue
-
-                if isinstance(arg, gcc.AddrExpr):
-                    arg = arg.operand
-
-                global cleanup_functions
-                if callee_name in cleanup_functions:
-                    if not isinstance(arg, gcc.FunctionDecl):
-                        gcc.inform(loc, 'cleanup argument not a DECL: %s' % repr(arg))
-                    else:
-                        # Cleanups must be nothrow.
-                        self.output_file.write("declare_cleanup(%s)\n"
-                                               % repr(str(arg.name)))
-                else:
-                    # Assume we have a passthrough function, like
-                    # qsort or an iterator.  We model this by
-                    # pretending there is an ordinary call at this
-                    # point.
-                    self.handle_one_fndecl(this_fun, arg, loc)
-        return try_catch
-
-    # Examine all the calls in a basic block and generate output for
-    # them.
-    # THIS_FUN is the enclosing function.
-    # BB is the basic block to examine.
-    # BB_WORKLIST is a list of basic blocks to work on; we add the
-    # appropriate successor blocks to this.
-    # SEEN_BBS is a map whose keys are basic blocks we have already
-    # processed.  We use this to ensure that we only visit a given
-    # block once.
-    def examine_one_bb(self, this_fun, bb, bb_worklist, seen_bbs):
-        try_catch = self.examine_one_bb_inner(this_fun, bb)
-        for edge in bb.succs:
-            if edge.dest in seen_bbs:
-                continue
-            seen_bbs[edge.dest] = 1
-            if try_catch:
-                # This is bogus, but we magically know the right
-                # answer.
-                if edge.false_value:
-                    bb_worklist.append(edge.dest)
-            else:
-                bb_worklist.append(edge.dest)
-
-    # Iterate over all basic blocks in THIS_FUN.
-    def iterate_bbs(self, this_fun):
-        # Iteration must be in control-flow order, because if we see a
-        # TRY_CATCH construct we need to drop all the contained blocks.
-        bb_worklist = [this_fun.cfg.entry]
-        seen_bbs = {}
-        seen_bbs[this_fun.cfg.entry] = 1
-        for bb in bb_worklist:
-            self.examine_one_bb(this_fun, bb, bb_worklist, seen_bbs)
-
-    def execute(self, fun):
-        if fun and fun.cfg and fun.decl:
-            self.output_file.write("################\n")
-            self.output_file.write("# Analysis for %s\n" % fun.decl.name)
-            self.output_file.write("define_function(%s, %s)\n"
-                                   % (repr(fun.decl.name),
-                                      repr(str(fun.decl.location))))
-
-            global ignore_functions
-            if fun.decl.name not in ignore_functions:
-                self.iterate_bbs(fun)
-
-def main(**kwargs):
-    global output_file
-    output_file = open(gcc.get_dump_base_name() + '.gdb_exc.py', 'w')
-    # We used to use attributes here, but there didn't seem to be a
-    # big benefit over hard-coding.
-    output_file.write('declare_throw("throw_exception")\n')
-    output_file.write('declare_throw("throw_verror")\n')
-    output_file.write('declare_throw("throw_vfatal")\n')
-    output_file.write('declare_throw("throw_error")\n')
-    gcc.register_callback(gcc.PLUGIN_FINISH_UNIT, close_output)
-    ps = GdbExceptionChecker(output_file)
-    ps.register_after('ssa')
-
-main()