File gcc48-bnc981311.diff of Package cross-hppa-gcc48-icecream-backend.8471
This is a backport of the fix for PR63293, which hit us
in the kernel (at least btrfs) as bnc #981311.
Index: gcc/config/aarch64/aarch64.c
===================================================================
--- gcc/config/aarch64/aarch64.c (revision 238821)
+++ gcc/config/aarch64/aarch64.c (working copy)
@@ -1995,6 +1995,9 @@ aarch64_expand_epilogue (bool for_sibcal
HOST_WIDE_INT fp_offset;
rtx insn;
rtx cfa_reg;
+ /* We need to add memory barrier to prevent read from deallocated stack. */
+ bool need_barrier_p = (get_frame_size () != 0
+ || cfun->machine->saved_varargs_size);
aarch64_layout_frame ();
original_frame_size = get_frame_size () + cfun->machine->saved_varargs_size;
@@ -2036,6 +2039,8 @@ aarch64_expand_epilogue (bool for_sibcal
if (frame_pointer_needed
&& (crtl->outgoing_args_size || cfun->calls_alloca))
{
+ if (cfun->calls_alloca)
+ emit_insn (gen_stack_tie (stack_pointer_rtx, stack_pointer_rtx));
insn = emit_insn (gen_add3_insn (stack_pointer_rtx,
hard_frame_pointer_rtx,
GEN_INT (- fp_offset)));
@@ -2049,6 +2054,9 @@ aarch64_expand_epilogue (bool for_sibcal
aarch64_save_or_restore_callee_save_registers
(fp_offset + cfun->machine->frame.hardfp_offset, 1);
+ if (need_barrier_p)
+ emit_insn (gen_stack_tie (stack_pointer_rtx, stack_pointer_rtx));
+
/* Restore the frame pointer and lr if the frame pointer is needed. */
if (offset > 0)
{
@@ -2146,6 +2154,9 @@ aarch64_expand_epilogue (bool for_sibcal
if (frame_size > -1)
{
+ if (need_barrier_p)
+ emit_insn (gen_stack_tie (stack_pointer_rtx, stack_pointer_rtx));
+
if (frame_size >= 0x1000000)
{
rtx op0 = gen_rtx_REG (Pmode, IP0_REGNUM);