+ forceRegDump :: CodeGen e s ()
+ forceRegDump = do
+ push esi
+ mov esi (0x13371234 :: Word32)
+ mov esi (Addr 0)
+ pop esi
+
+ getCurrentOffset :: CodeGen e s Word32
+ getCurrentOffset = do
+ ep <- getEntryPoint
+ let w32_ep = (fromIntegral $ ptrToIntPtr ep) :: Word32
+ offset <- getCodeOffset
+ return $ w32_ep + fromIntegral offset
+
+ emitInvoke :: Word16 -> Bool -> CodeGen e s (Maybe (Word32, TrapCause))
+ emitInvoke cpidx hasThis = do
+ let l = buildMethodID cls cpidx
+ calladdr <- getCurrentOffset
+ newNamedLabel (show l) >>= defineLabel
+ -- causes SIGILL. in the signal handler we patch it to the acutal call.
+ -- place two nop's at the end, therefore the disasm doesn't screw up
+ emit32 (0x9090ffff :: Word32); nop
+ -- discard arguments on stack
+ let argcnt = ((if hasThis then 1 else 0) + methodGetArgsCount (methodNameTypeByIdx cls cpidx)) * ptrSize
+ when (argcnt > 0) (add esp argcnt)
+ -- push result on stack if method has a return value
+ when (methodHaveReturnValue cls cpidx) (push eax)
+ return $ Just (calladdr, StaticMethod l)
+
+ virtualCall :: Word16 -> Bool -> CodeGen e s (Maybe (Word32, TrapCause))
+ virtualCall cpidx isInterface = do
+ let mi@(MethodInfo methodname objname msig@(MethodSignature args _)) = buildMethodID cls cpidx
+ newNamedLabel (show mi) >>= defineLabel
+ -- get method offset for call @ runtime
+ let offset = if isInterface
+ then getInterfaceMethodOffset objname methodname (encode msig)
+ else getMethodOffset objname (methodname `B.append` encode msig)
+ let argsLen = genericLength args
+ -- objref lives somewhere on the argument stack
+ mov ebx (Disp (argsLen * ptrSize), esp)
+ if isInterface
+ then mov ebx (Disp 0, ebx) -- get method-table-ptr, keep it in ebx
+ else return () -- invokevirtual
+ -- get method-table-ptr (or interface-table-ptr)
+ mov eax (Disp 0, ebx)
+ -- make actual (indirect) call
+ calladdr <- getCurrentOffset
+ -- will be patched to this: call (Disp 0xXXXXXXXX, eax)
+ emit32 (0x9090ffff :: Word32); nop; nop
+ -- discard arguments on stack (`+1' for "this")
+ let argcnt = ptrSize * (1 + methodGetArgsCount (methodNameTypeByIdx cls cpidx))
+ when (argcnt > 0) (add esp argcnt)
+ -- push result on stack if method has a return value
+ when (methodHaveReturnValue cls cpidx) (push eax)
+ -- note, that "mi" has the wrong class reference here.
+ -- we figure that out at run-time, in the methodpool,
+ -- depending on the method-table-ptr
+ return $ Just (calladdr, VirtualCall isInterface mi offset)
+
+ emit'' :: J.Instruction -> CodeGen e s (Maybe (Word32, TrapCause))
+ emit'' insn = newNamedLabel ("jvm_insn: " ++ show insn) >>= defineLabel >> emit' insn
+
+ emit' :: J.Instruction -> CodeGen e s (Maybe (Word32, TrapCause))
+ emit' (INVOKESPECIAL cpidx) = emitInvoke cpidx True
+ emit' (INVOKESTATIC cpidx) = emitInvoke cpidx False
+ emit' (INVOKEINTERFACE cpidx _) = virtualCall cpidx True
+ emit' (INVOKEVIRTUAL cpidx) = virtualCall cpidx False
+ emit' (PUTSTATIC cpidx) = do
+ pop eax
+ trapaddr <- getCurrentOffset
+ mov (Addr 0x00000000) eax -- it's a trap
+ return $ Just (trapaddr, StaticField $ buildStaticFieldID cls cpidx)
+ emit' (GETSTATIC cpidx) = do
+ trapaddr <- getCurrentOffset
+ mov eax (Addr 0x00000000) -- it's a trap
+ push eax
+ return $ Just (trapaddr, StaticField $ buildStaticFieldID cls cpidx)
+ emit' (INSTANCEOF cpidx) = do
+ pop eax
+ mov eax (Disp 0, eax) -- mtable of objectref
+ trapaddr <- getCurrentOffset
+ -- place something like `mov edx $mtable_of_objref' instead
+ emit32 (0x9090ffff :: Word32); nop
+ cmp eax edx
+ sete al
+ movzxb eax al
+ push eax
+ forceRegDump
+ return $ Just (trapaddr, InstanceOf $ buildClassID cls cpidx)
+ emit' (NEW objidx) = do
+ let objname = buildClassID cls objidx
+ trapaddr <- getCurrentOffset
+ -- place something like `push $objsize' instead
+ emit32 (0x9090ffff :: Word32); nop
+ callMalloc
+ -- 0x13371337 is just a placeholder; will be replaced with mtable ptr
+ mov (Disp 0, eax) (0x13371337 :: Word32)
+ return $ Just (trapaddr, NewObject objname)
+
+ emit' insn = emit insn >> return Nothing
+