class IrvmFrame(Frame):
"""Frame for an ARM function."""
# Word size for the target architecture.
word_size = 4
param_regs = [Temp("i%d" % i) for i in range(4)]
# Predefined registers used at many places.
rv = Temp("rv")
sp = Temp("sp")
fp = Temp("fp")
# List of callee save registers.
callee_save = []
# List of caller save registers.
# caller_save = list(Temp("i%d" % i) for i in range(0, 4))
caller_save = []
def __init__(self, label):
super().__init__(label)
self.end_label = Label("end")
def wrap_result(self, sxp):
super().wrap_result(sxp)
return MOVE(TEMP(self.rv), sxp)
def label_name(self, suffix):
return "L%s" % suffix
def allocate_frame_size(self):
return MOVE(TEMP(self.sp), BINOP('-', TEMP(self.sp),
CONST(self.offset)))
class ArmFrame(Frame):
"""Frame for an ARM function."""
# Word size for the target architecture.
word_size = 4
param_regs = [Temp("r0"), Temp("r1"), Temp("r2"), Temp("r3")]
# Predefined registers used at many places.
r0 = Temp("r0")
lr = Temp("lr")
sp = Temp("sp")
fp = Temp("r11")
# List of callee save registers.
callee_save = list(Temp("r%d" % i) for i in range(4, 11))
# List of caller save registers.
caller_save = list(Temp("r%d" % i) for i in range(0, 4))
def __init__(self, label):
super().__init__(label)
def wrap_result(self, sxp):
super().wrap_result(sxp)
return MOVE(TEMP(self.r0), sxp)
def decorate(self, stm):
"""Decorate the `stm` with code which sets up the frame, the stack
pointer, the registers holding the parameters, the preservation of
the callee saved registers, and the end label."""
# Begin and end label creation
begin_label = [LABEL(self.label)]
end_label = [LABEL(self.end_label)]
# If we are in the main function, we do not need to save or restore
# anything.
if self.label.name == 'main':
return SEQ(begin_label + [stm] + end_label)
# Code to save and restore the previous frame pointer and set-it up
# wrt the stack pointer. Also, a label is put at the place where the
# frame size will be allocated later (we will only know this
# information once all the code has been generated and physical
# registers have been allocated).
saved_fp = Temp.create("savedfp")
save_fp = [
MOVE(TEMP(saved_fp), TEMP(self.fp)),
MOVE(TEMP(self.fp), TEMP(self.sp)),
self.allocate_frame_size()
]
restore_fp = [
MOVE(TEMP(self.sp), TEMP(self.fp)),
MOVE(TEMP(self.fp), TEMP(saved_fp))
]
# Code to save the static link register into the frame at offset 0.
save_static_link = [MOVE(MEM(TEMP(self.fp)), TEMP(self.param_regs[0]))]
# Code to save and restore the callee-save registers.
callee_save_map = dict(
(reg, Temp.create("callee_save")) for reg in self.callee_save)
save_callee_save = [
MOVE(TEMP(callee_save_map[reg]), TEMP(reg))
for reg in self.callee_save
]
restore_callee_save = [
MOVE(TEMP(reg), TEMP(callee_save_map[reg]))
for reg in reversed(self.callee_save)
]
# Code to transfer the parameters from registers or call stack into the
# register or the frame position they belong to (according to their
# Access parameter). The first parameter (r0, in which the static link
# had been written) has already been handled above.
store_parameters = \
[MOVE(access.toSxp(self.fp),
TEMP(self.param_regs[idx + 1])
if idx < self.max_params_in_regs - 1
else InFrame((idx - self.max_params_in_regs + 1) *
self.word_size).toSxp(self.fp))
for (idx, access) in enumerate(self.param_access)]
return SEQ(begin_label + save_fp + save_static_link +
save_callee_save + store_parameters + [stm] +
restore_callee_save + restore_fp + end_label)
def prologue(self):
save_callee_save, restore_callee_save = self.preserve_callee_save()
lr_temp = Temp.create("lr_save")
save_lr, restore_lr = MOVE(TEMP(lr_temp), TEMP(self.lr)), \
MOVE(TEMP(self.lr), TEMP(lr_temp))
store_parameters = self.transfer_parameters()
# The fp save and static link will be saved while generating the code
# with ARM specific instructions.
return [LABEL(self.label)] + self.allocate_frame_size() + \
[save_lr] + save_callee_save + store_parameters, \
restore_callee_save + [restore_lr]
class IrvmFrame(Frame):
"""Frame for a function."""
# Word size for the target architecture.
word_size = 4
# Infinite number of parameter registers in IRVM. 128 is close
# enough to infinity, right?
param_regs = [Temp("i%d" % i) for i in range(128)]
# Predefined registers used at many places.
rv = Temp("rv")
sp = Temp("sp")
fp = Temp("fp")
# List of callee save registers.
callee_save = []
# List of caller save registers.
# caller_save = list(Temp("i%d" % i) for i in range(0, 4))
caller_save = []
def __init__(self, label):
super().__init__(label)
self.end_label = Label("end")
def wrap_result(self, sxp):
super().wrap_result(sxp)
return MOVE(TEMP(self.rv), sxp)
def label_name(self, suffix):
return "L%s" % suffix
def allocate_frame_size(self):
"""In IRVM, we know the frame size at this stage already since
we have an infinite number of registers and thus no spills."""
return [MOVE(TEMP(self.sp),
BINOP('+', TEMP(self.sp), CONST(-self.offset)))] \
if self.offset else []
def preserve_callee_save(self):
"""Save all the callee save registers and return
a list of move instructions to save them and a list
of move instructions to restore them."""
callee_save_map = dict(
(reg, Temp.create("callee_save")) for reg in self.callee_save)
save_callee_save = [
MOVE(TEMP(callee_save_map[reg]), TEMP(reg))
for reg in self.callee_save
]
restore_callee_save = [
MOVE(TEMP(reg), TEMP(callee_save_map[reg]))
for reg in reversed(self.callee_save)
]
return save_callee_save, restore_callee_save
def __init__(self, prefix=None):
self.temp = TEMP(Temp.create(prefix))
class ArmFrame(Frame):
"""Frame for an ARM function."""
# Word size for the target architecture.
word_size = 4
param_regs = [Temp("r0"), Temp("r1"), Temp("r2"), Temp("r3")]
# Predefined registers used at many places.
r0 = Temp("r0")
lr = Temp("lr")
sp = Temp("sp")
fp = Temp("r11")
# List of callee save registers (the frame pointer is handled separately).
callee_save = list(Temp("r%d" % i) for i in range(4, 11))
# List of caller save registers.
caller_save = list(Temp("r%d" % i) for i in range(4)) + [lr]
# All physical registers appearing in code, used for register allocation.
registers = list(Temp("r%d" % i) for i in range(11)) + [sp, lr, fp]
def __init__(self, label):
super().__init__(label)
def wrap_result(self, sxp):
super().wrap_result(sxp)
return MOVE(TEMP(self.r0), sxp)
def prologue(self):
save_callee_save, restore_callee_save = self.preserve_callee_save()
lr_temp = Temp.create("lr_save")
save_lr, restore_lr = MOVE(TEMP(lr_temp), TEMP(self.lr)), \
MOVE(TEMP(self.lr), TEMP(lr_temp))
store_parameters = self.transfer_parameters()
# The fp save and static link will be saved while generating the code
# with ARM specific instructions.
return [LABEL(self.label)] + self.allocate_frame_size() + \
[save_lr] + save_callee_save + store_parameters, \
restore_callee_save + [restore_lr]
def epilogue(self, data):
return [LABEL(self.restore_label)] + data + [LABEL(self.end_label)]
def load_spill(self, temp, offset):
assert isinstance(temp, Temp)
assert isinstance(offset, int)
return [
O("ldr {{}}, [{{}}, #{:d}]".format(offset),
dsts=[temp],
srcs=[self.fp])
]
def save_spill(self, temp, offset):
assert isinstance(temp, Temp)
assert isinstance(offset, int)
return [
O("str {{}}, [{{}}, #{:d}]".format(offset), srcs=[temp, self.fp])
]
def reserve_stack_space(self):
return [O("add {{}}, {{}}, #-{}".format(self.offset), dsts=[self.sp], srcs=[self.sp])] \
if self.offset else []