def test_ControlFlowGraphFromDotSource_is_valid():
"""Test that CFG is valid."""
g = llvm_util.ControlFlowGraphFromDotSource(SIMPLE_C_DOT)
# Control flow graphs are not guaranteed to be valid. That is, the may contain
# fusible basic blocks. This can happen if the creating the graph from
# unoptimized bytecode.
assert g.ValidateControlFlowGraph()
def test_ControlFlowGraphFromDotSource_edges():
"""Test that CFG edges are as expected."""
g = llvm_util.ControlFlowGraphFromDotSource(SIMPLE_C_DOT)
node_name_to_index_map = {g.nodes[n]["name"]: n for n in g.nodes}
edges = set(g.edges)
assert (node_name_to_index_map['%2'],
node_name_to_index_map['%9']) in edges
assert (node_name_to_index_map['%2'],
node_name_to_index_map['%12']) in edges
assert (node_name_to_index_map['%9'],
node_name_to_index_map['%18']) in edges
assert (node_name_to_index_map['%12'],
node_name_to_index_map['%18']) in edges
def TryToCreateControlFlowGraphsFromLinuxSrc(
path: pathlib.Path) -> typing.Optional[cfg.ControlFlowGraph]:
"""Try to create CFGs from a Linux C source file.
On failure, an empty list is returned.
Args:
path: The path of the source file.
Returns:
A list of ControlFlowGraph instances.
Raises:
ClangException: If compiling to bytecode fails.
"""
graphs = []
try:
bytecode = BytecodeFromLinuxSrc(path)
except clang.ClangException:
return graphs
# Extract a dot sources from the bytecode.
dot_generator = llvm_util.DotCfgsFromBytecode(bytecode)
while True:
try:
dot = next(dot_generator)
# Instantiate a CFG from the dot source.
graph = llvm_util.ControlFlowGraphFromDotSource(dot)
graph.ValidateControlFlowGraph(strict=False)
graphs.append(graph)
except (UnicodeDecodeError, cfg.MalformedControlFlowGraphError,
ValueError, opt.OptException, pyparsing.ParseException):
pass
except StopIteration:
break
return graphs
def CreateControlFlowGraphFromOpenClKernel(
kernel_name: str,
opencl_kernel: str) -> typing.Optional[cfg.ControlFlowGraph]:
"""Try to create a CFG proto from an opencl kernel.
Args:
kernel_name: The name of the OpenCL kernel defined in opencl_kernel.
opencl_kernel: A string of OpenCL. This should contain a single kernel
definition.
Returns:
A ControlFlowGraph instance, or None if compilation to bytecode fails.
Raises:
ClangException: If compiling to bytecode fails.
ValueError: If opencl_kernel contains multiple functions.
"""
bytecode = BytecodeFromOpenClString(opencl_kernel)
# Extract a single dot source from the bytecode.
dot_generator = llvm_util.DotCfgsFromBytecode(bytecode)
dot = next(dot_generator)
try:
next(dot_generator)
raise ValueError("Bytecode produced more than one dot source!")
except StopIteration:
pass
# Instantiate a CFG from the dot source.
graph = llvm_util.ControlFlowGraphFromDotSource(dot)
# Set the name of the graph to the kernel name. This is because the src code
# has been preprocessed, so that each kernel is named 'A'.
graph.graph['name'] = kernel_name
return graph
def test_ControlFlowGraphFromDotSource_node_names():
"""Test that CFG names are as expected."""
g = llvm_util.ControlFlowGraphFromDotSource(SIMPLE_C_DOT)
node_names = sorted([g.nodes[n]['name'] for n in g.nodes],
key=lambda x: int(x[1:]))
assert node_names == ['%2', '%9', '%12', '%18']
def test_ControlFlowGraphFromDotSource_num_edges():
"""Test that CFG has correct number of edges."""
g = llvm_util.ControlFlowGraphFromDotSource(SIMPLE_C_DOT)
assert g.number_of_edges() == 4
def test_ControlFlowGraphFromDotSource_graph_name():
"""Test that CFG has correct name."""
g = llvm_util.ControlFlowGraphFromDotSource(SIMPLE_C_DOT)
assert g.graph['name'] == 'DoSomething'
def test_ControlFlowGraphFromDotSource_invalid_source():
"""Test that exception is raised if dot can't be parsed."""
with pytest.raises(pyparsing.ParseException):
llvm_util.ControlFlowGraphFromDotSource("invalid dot source!")