llvm_ir: fixed stack leak on ffi call

This commit is contained in:
Timothy Ballance 2022-03-21 19:56:02 +00:00 committed by Sébastien Bourdeauducq
parent f89275b02a
commit a289d69883
1 changed files with 20 additions and 4 deletions

View File

@ -1359,11 +1359,24 @@ class LLVMIRGenerator:
else:
llfun = self.map(insn.static_target_function)
llenv = self.llbuilder.extract_value(llclosure, 0, name="env.fun")
return llfun, [llenv] + list(llargs), {}
return llfun, [llenv] + list(llargs), {}, None
def _prepare_ffi_call(self, insn):
llargs = []
llarg_attrs = {}
stack_save_needed = False
for i, arg in enumerate(insn.arguments()):
llarg = self.map(arg)
if isinstance(llarg.type, (ll.LiteralStructType, ll.IdentifiedStructType)):
stack_save_needed = True
break
if stack_save_needed:
llcallstackptr = self.llbuilder.call(self.llbuiltin("llvm.stacksave"), [])
else:
llcallstackptr = None
for i, arg in enumerate(insn.arguments()):
llarg = self.map(arg)
if isinstance(llarg.type, (ll.LiteralStructType, ll.IdentifiedStructType)):
@ -1399,7 +1412,7 @@ class LLVMIRGenerator:
if 'nowrite' in insn.target_function().type.flags:
llfun.attributes.add('inaccessiblememonly')
return llfun, list(llargs), llarg_attrs
return llfun, list(llargs), llarg_attrs, llcallstackptr
def _build_rpc(self, fun_loc, fun_type, args, llnormalblock, llunwindblock):
llservice = ll.Constant(lli32, fun_type.service)
@ -1535,9 +1548,9 @@ class LLVMIRGenerator:
insn.arguments(),
llnormalblock=None, llunwindblock=None)
elif types.is_external_function(functiontyp):
llfun, llargs, llarg_attrs = self._prepare_ffi_call(insn)
llfun, llargs, llarg_attrs, llcallstackptr = self._prepare_ffi_call(insn)
else:
llfun, llargs, llarg_attrs = self._prepare_closure_call(insn)
llfun, llargs, llarg_attrs, llcallstackptr = self._prepare_closure_call(insn)
if self.has_sret(functiontyp):
llstackptr = self.llbuilder.call(self.llbuiltin("llvm.stacksave"), [])
@ -1556,6 +1569,9 @@ class LLVMIRGenerator:
# {} elsewhere.
llresult = ll.Constant(llunit, [])
if llcallstackptr != None:
self.llbuilder.call(self.llbuiltin("llvm.stackrestore"), [llcallstackptr])
return llresult
def process_Invoke(self, insn):