Author: Armin Rigo <[email protected]>
Branch:
Changeset: r63374:154e81a46200
Date: 2013-04-15 17:50 +0200
http://bitbucket.org/pypy/pypy/changeset/154e81a46200/
Log: Clean up the number and significance of the various flags
"can_collect", "reload_frame" etc. and hopefully fix asmgcc.
diff --git a/rpython/jit/backend/x86/assembler.py
b/rpython/jit/backend/x86/assembler.py
--- a/rpython/jit/backend/x86/assembler.py
+++ b/rpython/jit/backend/x86/assembler.py
@@ -112,6 +112,11 @@
self.float_const_neg_addr = float_constants
self.float_const_abs_addr = float_constants + 16
+ def set_extra_stack_depth(self, mc, value):
+ if self._is_asmgcc():
+ extra_ofs = self.cpu.get_ofs_of_frame_field('jf_extra_stack_depth')
+ mc.MOV_bi(extra_ofs, value)
+
def build_frame_realloc_slowpath(self):
mc = codebuf.MachineCodeBlockWrapper()
self._push_all_regs_to_frame(mc, [], self.cpu.supports_floats)
@@ -134,16 +139,14 @@
mc.MOV_sr(0, ebp.value)
# align
- extra_ofs = self.cpu.get_ofs_of_frame_field('jf_extra_stack_depth')
- mc.MOV_bi(extra_ofs, align * WORD)
+ self.set_extra_stack_depth(mc, align * WORD)
self._store_and_reset_exception(mc, None, ebx, ecx)
mc.CALL(imm(self.cpu.realloc_frame))
mc.MOV_rr(ebp.value, eax.value)
self._restore_exception(mc, None, ebx, ecx)
mc.ADD_ri(esp.value, (align - 1) * WORD)
- mc.MOV_bi(extra_ofs, 0)
-
+ self.set_extra_stack_depth(mc, 0)
gcrootmap = self.cpu.gc_ll_descr.gcrootmap
if gcrootmap and gcrootmap.is_shadow_stack:
@@ -176,8 +179,7 @@
elif hasattr(self.cpu.gc_ll_descr, 'passes_frame'):
# for tests only
mc.MOV_rr(esi.value, ebp.value)
- extra_ofs = self.cpu.get_ofs_of_frame_field('jf_extra_stack_depth')
- mc.MOV_bi(extra_ofs, 16)
+ self.set_extra_stack_depth(mc, 16)
mc.CALL(imm(addr))
mc.ADD_ri(esp.value, 16 - WORD)
mc.TEST_rr(eax.value, eax.value)
@@ -186,7 +188,7 @@
#
nursery_free_adr = self.cpu.gc_ll_descr.get_nursery_free_addr()
self._reload_frame_if_necessary(mc, align_stack=True)
- mc.MOV_bi(extra_ofs, 0)
+ self.set_extra_stack_depth(mc, 0)
self._pop_all_regs_from_frame(mc, [eax, edi], self.cpu.supports_floats)
mc.MOV(edi, heap(nursery_free_adr)) # load this in EDI
# clear the gc pattern
@@ -973,14 +975,17 @@
return bool(gcrootmap) and not gcrootmap.is_shadow_stack
def _emit_call(self, x, arglocs, start=0, tmp=eax,
- argtypes=None, callconv=FFI_DEFAULT_ABI, can_collect=1,
- stack_max=PASS_ON_MY_FRAME, reload_frame=False):
- if can_collect == 1 and not self._is_asmgcc():
- can_collect = 2 # don't bother with jf_extra_stack_depth
+ argtypes=None, callconv=FFI_DEFAULT_ABI,
+ # whether to worry about a CALL that can collect; this
+ # is always true except in call_release_gil
+ can_collect=True,
+ # max number of arguments we can pass on esp; if more,
+ # we need to decrease esp temporarily
+ stack_max=PASS_ON_MY_FRAME):
+ #
if IS_X86_64:
return self._emit_call_64(x, arglocs, start, argtypes,
- can_collect, stack_max,
- reload_frame=reload_frame)
+ can_collect, stack_max)
stack_depth = 0
n = len(arglocs)
for i in range(start, n):
@@ -989,9 +994,8 @@
if stack_depth > stack_max:
align = align_stack_words(stack_depth - stack_max)
self.mc.SUB_ri(esp.value, align * WORD)
- if can_collect == 1:
- ofs = self.cpu.get_ofs_of_frame_field('jf_extra_stack_depth')
- self.mc.MOV_bi(ofs, align * WORD)
+ if can_collect:
+ self.set_extra_stack_depth(self.mc, align * WORD)
else:
align = 0
p = 0
@@ -1016,23 +1020,24 @@
p += loc.get_width()
# x is a location
if can_collect:
+ # we push *now* the gcmap, describing the status of GC registers
+ # after the rearrangements done just above, ignoring the return
+ # value eax, if necessary
noregs = self.cpu.gc_ll_descr.is_shadow_stack()
gcmap = self._regalloc.get_gcmap([eax], noregs=noregs)
self.push_gcmap(self.mc, gcmap, store=True)
+ #
self.mc.CALL(x)
if callconv != FFI_DEFAULT_ABI:
self._fix_stdcall(callconv, p - align * WORD)
elif align:
self.mc.ADD_ri(esp.value, align * WORD)
+ #
if can_collect:
- self._reload_frame_if_necessary(self.mc, can_collect=can_collect)
- if align and can_collect == 1:
- ofs = self.cpu.get_ofs_of_frame_field('jf_extra_stack_depth')
- self.mc.MOV_bi(ofs, 0)
+ self._reload_frame_if_necessary(self.mc)
+ if align:
+ self.set_extra_stack_depth(self.mc, 0)
self.pop_gcmap(self.mc)
- elif reload_frame:
- self._reload_frame_if_necessary(self.mc)
- #
def _fix_stdcall(self, callconv, p):
from rpython.rlib.clibffi import FFI_STDCALL
@@ -1042,7 +1047,7 @@
self.mc.SUB_ri(esp.value, p)
def _emit_call_64(self, x, arglocs, start, argtypes,
- can_collect, stack_max, reload_frame=False):
+ can_collect, stack_max):
src_locs = []
dst_locs = []
xmm_src_locs = []
@@ -1066,9 +1071,8 @@
align = 0
if stack_depth > stack_max:
align = align_stack_words(stack_depth - stack_max)
- if can_collect == 1:
- ofs = self.cpu.get_ofs_of_frame_field('jf_extra_stack_depth')
- self.mc.MOV_bi(ofs, align * WORD)
+ if can_collect:
+ self.set_extra_stack_depth(self.mc, align * WORD)
self.mc.SUB_ri(esp.value, align * WORD)
for i in range(start, len(arglocs)):
loc = arglocs[i]
@@ -1123,35 +1127,30 @@
x = r10
remap_frame_layout(self, src_locs, dst_locs, X86_64_SCRATCH_REG)
if can_collect:
+ # we push *now* the gcmap, describing the status of GC registers
+ # after the rearrangements done just above, ignoring the return
+ # value eax, if necessary
noregs = self.cpu.gc_ll_descr.is_shadow_stack()
gcmap = self._regalloc.get_gcmap([eax], noregs=noregs)
self.push_gcmap(self.mc, gcmap, store=True)
+ #
self.mc.CALL(x)
- if can_collect:
- self._reload_frame_if_necessary(self.mc, can_collect=can_collect)
- if align and can_collect == 1:
- ofs = self.cpu.get_ofs_of_frame_field('jf_extra_stack_depth')
- self.mc.MOV_bi(ofs, 0)
- elif reload_frame:
- self._reload_frame_if_necessary(self.mc)
if align:
self.mc.ADD_ri(esp.value, align * WORD)
+ #
if can_collect:
+ self._reload_frame_if_necessary(self.mc)
+ if align:
+ self.set_extra_stack_depth(self.mc, 0)
self.pop_gcmap(self.mc)
- def _reload_frame_if_necessary(self, mc, align_stack=False, can_collect=0):
+ def _reload_frame_if_necessary(self, mc, align_stack=False):
gcrootmap = self.cpu.gc_ll_descr.gcrootmap
if gcrootmap:
if gcrootmap.is_shadow_stack:
rst = gcrootmap.get_root_stack_top_addr()
mc.MOV(ecx, heap(rst))
mc.MOV(ebp, mem(ecx, -WORD))
- elif can_collect == 3:
- # specially for call_release_gil: must reload ebp from the css
- from rpython.memory.gctransform import asmgcroot
- css = WORD * (PASS_ON_MY_FRAME - asmgcroot.JIT_USE_WORDS)
- index_of_ebp = css + WORD * (2+asmgcroot.INDEX_OF_EBP)
- mc.MOV_rs(ebp.value, index_of_ebp) # MOV EBP, [css.ebp]
wbdescr = self.cpu.gc_ll_descr.write_barrier_descr
if gcrootmap and wbdescr:
# frame never uses card marking, so we enforce this is not
@@ -1950,12 +1949,9 @@
if self._is_asmgcc():
from rpython.memory.gctransform import asmgcroot
stack_max -= asmgcroot.JIT_USE_WORDS
- can_collect = 3 # asmgcc only: don't write
jf_extra_stack_depth,
- # and reload ebp from the css
- else:
- can_collect = 0
+ can_collect = False
else:
- can_collect = 1
+ can_collect = True
self._emit_call(x, arglocs, 3, tmp=tmp,
argtypes=descr.get_arg_types(),
@@ -2022,8 +2018,13 @@
# first, close the stack in the sense of the asmgcc GC root tracker
gcrootmap = self.cpu.gc_ll_descr.gcrootmap
if gcrootmap:
- noregs = self.cpu.gc_ll_descr.is_shadow_stack()
- gcmap = self._regalloc.get_gcmap([eax], noregs=noregs)
+ # we put the gcmap now into the frame before releasing the GIL,
+ # and pop it below after reacquiring the GIL. The assumption
+ # is that this gcmap describes correctly the situation at any
+ # point in-between: all values containing GC pointers should
+ # be safely saved out of registers by now, and will not be
+ # manipulated by any of the following CALLs.
+ gcmap = self._regalloc.get_gcmap(noregs=True)
self.push_gcmap(self.mc, gcmap, store=True)
self.call_release_gil(gcrootmap, arglocs)
# do the call
@@ -2031,6 +2032,7 @@
# then reopen the stack
if gcrootmap:
self.call_reacquire_gil(gcrootmap, result_loc)
+ self.pop_gcmap(self.mc) # remove the gcmap saved above
# finally, the guard_not_forced
self._emit_guard_not_forced(guard_token)
@@ -2059,8 +2061,7 @@
# Set up jf_extra_stack_depth to pretend that the return address
# was at css, and so our stack frame is supposedly shorter by
# (css+WORD) bytes
- extra_ofs = self.cpu.get_ofs_of_frame_field('jf_extra_stack_depth')
- self.mc.MOV_bi(extra_ofs, -css-WORD)
+ self.set_extra_stack_depth(self.mc, -css-WORD)
# Call the closestack() function (also releasing the GIL)
args = [reg]
#
@@ -2075,19 +2076,29 @@
# call the reopenstack() function (also reacquiring the GIL)
if gcrootmap.is_shadow_stack:
args = []
+ css = 0
else:
from rpython.memory.gctransform import asmgcroot
css = WORD * (PASS_ON_MY_FRAME - asmgcroot.JIT_USE_WORDS)
- extra_ofs = self.cpu.get_ofs_of_frame_field('jf_extra_stack_depth')
- self.mc.MOV_bi(extra_ofs, 0)
if IS_X86_32:
reg = eax
elif IS_X86_64:
reg = edi
self.mc.LEA_rs(reg.value, css)
args = [reg]
- self._emit_call(imm(self.reacqgil_addr), args, can_collect=False,
- reload_frame=True)
+ self._emit_call(imm(self.reacqgil_addr), args, can_collect=False)
+ #
+ # Now that we required the GIL, we can reload a possibly modified ebp
+ if not gcrootmap.is_shadow_stack:
+ # special-case: reload ebp from the css
+ from rpython.memory.gctransform import asmgcroot
+ index_of_ebp = css + WORD * (2+asmgcroot.INDEX_OF_EBP)
+ mc.MOV_rs(ebp.value, index_of_ebp) # MOV EBP, [css.ebp]
+ #else:
+ # for shadowstack, done for us by _reload_frame_if_necessary()
+ self._reload_frame_if_necessary(self.mc)
+ self.set_extra_stack_depth(self.mc, 0)
+ #
# restore the result from the stack
if isinstance(save_loc, RegLoc) and not save_loc.is_xmm:
self.mc.MOV_rs(save_loc.value, WORD)
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