import shutil, time, os
from subprocess import Popen, PIPE, STDOUT

__rootpath__ = os.path.abspath(os.path.dirname(os.path.dirname(__file__)))
def path_from_root(*pathelems):
  return os.path.join(__rootpath__, *pathelems)

CONFIG_FILE = os.path.expanduser('~/.emscripten')
if not os.path.exists(CONFIG_FILE):
  shutil.copy(path_from_root('settings.py'), CONFIG_FILE)
exec(open(CONFIG_FILE, 'r').read())

# Tools

CLANG=os.path.expanduser(os.path.join(LLVM_ROOT, 'clang++'))
LLVM_LINK=os.path.join(LLVM_ROOT, 'llvm-link')
LLVM_LD=os.path.join(LLVM_ROOT, 'llvm-ld')
LLVM_OPT=os.path.expanduser(os.path.join(LLVM_ROOT, 'opt'))
LLVM_AS=os.path.expanduser(os.path.join(LLVM_ROOT, 'llvm-as'))
LLVM_DIS=os.path.expanduser(os.path.join(LLVM_ROOT, 'llvm-dis'))
LLVM_DIS_OPTS = ['-show-annotations'] # For LLVM 2.8+. For 2.7, you may need to do just    []
LLVM_INTERPRETER=os.path.expanduser(os.path.join(LLVM_ROOT, 'lli'))
LLVM_COMPILER=os.path.expanduser(os.path.join(LLVM_ROOT, 'llc'))

BINDINGS_GENERATOR = path_from_root('tools', 'bindings_generator.py')
EXEC_LLVM = path_from_root('tools', 'exec_llvm.py')

# Additional compiler options

USE_EMSDK = True

COMPILER_OPTS = COMPILER_OPTS + ['-m32', '-v', '-U__i386__', '-U__x86_64__', '-U__i386', '-U__x86_64', '-U__SSE__', '-U__SSE2__', '-U__MMX__',
                                 '-UX87_DOUBLE_ROUNDING', '-UHAVE_GCC_ASM_FOR_X87', '-DEMSCRIPTEN', '-U__STRICT_ANSI__']

if USE_EMSDK:
  COMPILER_OPTS += [ '-nostdinc',
  '-I' + path_from_root('system', 'include'),
  '-I' + path_from_root('system', 'include', 'bsd'), # posix stuff
  '-I' + path_from_root('system', 'include', 'libc'),
  '-I' + path_from_root('system', 'include', 'libcxx'),
  '-I' + path_from_root('system', 'include', 'gfx'),
  '-I' + path_from_root('system', 'include', 'net'),
  '-I' + path_from_root('system', 'include', 'SDL'),
]

# Engine tweaks

#if 'strict' not in str(SPIDERMONKEY_ENGINE): # XXX temporarily disable strict mode until we sort out some stuff
#  SPIDERMONKEY_ENGINE += ['-e', "options('strict')"] # Strict mode in SpiderMonkey. With V8 we check that fallback to non-strict works too

if 'gcparam' not in str(SPIDERMONKEY_ENGINE):
  SPIDERMONKEY_ENGINE += ['-e', "gcparam('maxBytes', 1024*1024*1024);"] # Our very large files need lots of gc heap

# Utilities

def timeout_run(proc, timeout, note):
  start = time.time()
  if timeout is not None:
    while time.time() - start < timeout and proc.poll() is None:
      time.sleep(0.1)
    if proc.poll() is None:
      proc.kill() # XXX bug: killing emscripten.py does not kill it's child process!
      raise Exception("Timed out: " + note)
  return proc.communicate()[0]

def run_js(engine, filename, args, check_timeout=False, stdout=PIPE, stderr=STDOUT, cwd=None):
  return timeout_run(Popen(engine + [filename] + (['--'] if 'd8' in engine[0] else []) + args,
                     stdout=stdout, stderr=stderr, cwd=cwd), 15*60 if check_timeout else None, 'Execution')

def to_cc(cxx):
  # By default, LLVM_GCC and CLANG are really the C++ versions. This gets an explicit C version
  return cxx.replace('clang++', 'clang').replace('g++', 'gcc')

def line_splitter(data):
  """Silly little tool to split JSON arrays over many lines."""

  out = ''
  counter = 0

  for i in range(len(data)):
    out += data[i]
    if data[i] == ' ' and counter > 60:
      out += '\n'
      counter = 0
    else:
      counter += 1

  return out

def limit_size(string, MAX=800*20):
  if len(string) < MAX: return string
  return string[0:MAX/2] + '\n[..]\n' + string[-MAX/2:]

def pick_llvm_opts(optimization_level, handpicked, quantum_size=4, use_aa=False):
  '''
    It may be safe to use nonportable optimizations (like -OX) if we remove the platform info from the .ll
    (which we do in do_ll_opts) - but even there we have issues (even in TA2) with instruction combining
    into i64s. In any case, the handpicked ones here should be safe and portable. They are also tuned for
    things that look useful.
  '''
  opts = []
  if optimization_level > 0:
    if not handpicked:
      opts.append('-O%d' % optimization_level)
    else:
      allow_nonportable = False
      optimize_size = True

      # PassManagerBuilder::populateModulePassManager
      if allow_nonportable and use_aa: # ammo.js results indicate this can be nonportable
        opts.append('-tbaa')
        opts.append('-basicaa') # makes fannkuch slow but primes fast

      opts.append('-globalopt')
      opts.append('-ipsccp')
      opts.append('-deadargelim')
      if allow_nonportable: opts.append('-instcombine')
      opts.append('-simplifycfg')

      opts.append('-prune-eh')
      if not optimize_size: opts.append('-inline') # The condition here is a difference with LLVM's createStandardAliasAnalysisPasses
      opts.append('-functionattrs')
      if optimization_level > 2:
        opts.append('-argpromotion')

      # XXX Danger: Can turn a memcpy into something that violates the
      #             load-store consistency hypothesis. See hashnum() in Lua.
      #             Note: this opt is of great importance for raytrace...
      if allow_nonportable: opts.append('-scalarrepl')

      if allow_nonportable: opts.append('-early-cse') # ?
      opts.append('-simplify-libcalls')
      opts.append('-jump-threading')
      if allow_nonportable: opts.append('-correlated-propagation') # ?
      opts.append('-simplifycfg')
      if allow_nonportable: opts.append('-instcombine')

      opts.append('-tailcallelim')
      opts.append('-simplifycfg')
      opts.append('-reassociate')
      opts.append('-loop-rotate')
      opts.append('-licm')
      opts.append('-loop-unswitch') # XXX should depend on optimize_size
      if allow_nonportable: opts.append('-instcombine')
      if quantum_size == 4: opts.append('-indvars') # XXX this infinite-loops raytrace on q1 (loop in |new node_t[count]| has 68 hardcoded &not fixed)
      if allow_nonportable: opts.append('-loop-idiom') # ?
      opts.append('-loop-deletion')
      opts.append('-loop-unroll')

      ##### not in llvm-3.0. but have |      #addExtensionsToPM(EP_LoopOptimizerEnd, MPM);| if allow_nonportable: opts.append('-instcombine')

      # XXX Danger: Messes up Lua output for unknown reasons
      #             Note: this opt is of minor importance for raytrace...
      if optimization_level > 1 and allow_nonportable: opts.append('-gvn')

      opts.append('-memcpyopt') # Danger?
      opts.append('-sccp')

      if allow_nonportable: opts.append('-instcombine')
      opts.append('-jump-threading')
      opts.append('-correlated-propagation')
      opts.append('-dse')
      #addExtensionsToPM(EP_ScalarOptimizerLate, MPM);

      opts.append('-adce')
      opts.append('-simplifycfg')
      if allow_nonportable: opts.append('-instcombine')

      opts.append('-strip-dead-prototypes')

      if optimization_level > 2: opts.append('-globaldce')

      if optimization_level > 1: opts.append('-constmerge')

  return opts

def read_auto_optimize_data(filename):
  '''
    Reads the output of AUTO_OPTIMIZE and generates proper information for CORRECT_* == 2 's *_LINES options
  '''
  signs_lines = []
  overflows_lines = []
  
  for line in open(filename, 'r'):
    if line.rstrip() == '': continue
    if '%0 failures' in line: continue
    left, right = line.split(' : ')
    signature = left.split('|')[1]
    if 'Sign' in left:
      signs_lines.append(signature)
    elif 'Overflow' in left:
      overflows_lines.append(signature)

  return {
    'signs_lines': signs_lines,
    'overflows_lines': overflows_lines
  }