llvm-6502/bindings/python/llvm/core.py
Michael Gottesman 653212fdd1 [python bindings] Added code to get the length of a memory buffer. Tests are included.
This is a part of a series of patches that have been sitting fallow on a
personal branch that I have been messing with for a bit.

The patches start to flesh out the python llvm-c wrapper to the point where you can:

1. Load Modules from Bitcode/Dump/Print them.
2. Iterate over Functions from those modules/get their names/dump them.
3. Iterate over the BasicBlocks from said function/get the BB's name/dump it.
4. Iterate over the Instructions in said BasicBlocks/get the instructions
   name/dump the instruction.

My main interest in developing this was to be able to gather statistics about
LLVM IR using python scripts to speed up statistical profiling of different IR
level transformations (hence the focus on printing/dumping/getting names).

This is a gift from me to the LLVM community = ).

I am going to be committing the patches slowly over the next bit as I have time
to prepare the patches.

The overall organization follows the c-api like the bindings that are already
implemented.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@190388 91177308-0d34-0410-b5e6-96231b3b80d8
2013-09-10 06:57:57 +00:00

105 lines
2.9 KiB
Python

#===- core.py - Python LLVM Bindings -------------------------*- python -*--===#
#
# The LLVM Compiler Infrastructure
#
# This file is distributed under the University of Illinois Open Source
# License. See LICENSE.TXT for details.
#
#===------------------------------------------------------------------------===#
from .common import LLVMObject
from .common import c_object_p
from .common import get_library
from . import enumerations
from ctypes import POINTER
from ctypes import byref
from ctypes import c_char_p
__all__ = [
"lib",
"MemoryBuffer",
]
lib = get_library()
class OpCode(object):
"""Represents an individual OpCode enumeration."""
_value_map = {}
def __init__(self, name, value):
self.name = name
self.value = value
def __repr__(self):
return 'OpCode.%s' % self.name
@staticmethod
def from_value(value):
"""Obtain an OpCode instance from a numeric value."""
result = OpCode._value_map.get(value, None)
if result is None:
raise ValueError('Unknown OpCode: %d' % value)
return result
@staticmethod
def register(name, value):
"""Registers a new OpCode enumeration.
This is called by this module for each enumeration defined in
enumerations. You should not need to call this outside this module.
"""
if value in OpCode._value_map:
raise ValueError('OpCode value already registered: %d' % value)
opcode = OpCode(name, value)
OpCode._value_map[value] = opcode
setattr(OpCode, name, opcode)
class MemoryBuffer(LLVMObject):
"""Represents an opaque memory buffer."""
def __init__(self, filename=None):
"""Create a new memory buffer.
Currently, we support creating from the contents of a file at the
specified filename.
"""
if filename is None:
raise Exception("filename argument must be defined")
memory = c_object_p()
out = c_char_p(None)
result = lib.LLVMCreateMemoryBufferWithContentsOfFile(filename,
byref(memory), byref(out))
if result:
raise Exception("Could not create memory buffer: %s" % out.value)
LLVMObject.__init__(self, memory, disposer=lib.LLVMDisposeMemoryBuffer)
def __len__(self):
return lib.LLVMGetBufferSize(self)
def register_library(library):
# Memory buffer declarations
library.LLVMCreateMemoryBufferWithContentsOfFile.argtypes = [c_char_p,
POINTER(c_object_p), POINTER(c_char_p)]
library.LLVMCreateMemoryBufferWithContentsOfFile.restype = bool
library.LLVMGetBufferSize.argtypes = [MemoryBuffer]
library.LLVMDisposeMemoryBuffer.argtypes = [MemoryBuffer]
def register_enumerations():
for name, value in enumerations.OpCodes:
OpCode.register(name, value)
register_library(lib)
register_enumerations()