Add patch for bug #334269 (kernel miscompile).

2 files changed, 182 insertions, 0 deletions

diff --git a/4.4.4/gentoo/50_all_pr45312-kernel-miscompile.patch b/4.4.4/gentoo/50_all_pr45312-kernel-miscompile.patch
new file mode 100644
index 0000000..b9b1a7d
--- /dev/null
+++ b/4.4.4/gentoo/50_all_pr45312-kernel-miscompile.patch
@@ -0,0 +1,181 @@
+GCC 4.4.4 miscompiles the Linux kernel
+http://gcc.gnu.org/PR45312
+https://bugzilla.kernel.org/show_bug.cgi?id=16612
+https://bugs.gentoo.org/334269
+
+--- a/gcc/reload1.c
++++ b/gcc/reload1.c
+@@ -431,7 +431,6 @@ static void failed_reload (rtx, int);
+ static int set_reload_reg (int, int);
+ static void choose_reload_regs_init (struct insn_chain *, rtx *);
+ static void choose_reload_regs (struct insn_chain *);
+-static void merge_assigned_reloads (rtx);
+ static void emit_input_reload_insns (struct insn_chain *, struct reload *,
+ 				     rtx, int);
+ static void emit_output_reload_insns (struct insn_chain *, struct reload *,
+@@ -4215,12 +4214,6 @@ reload_as_needed (int live_known)
+ 		 Record the choices of reload reg in reload_reg_rtx.  */
+ 	      choose_reload_regs (chain);
+ 
+-	      /* Merge any reloads that we didn't combine for fear of
+-		 increasing the number of spill registers needed but now
+-		 discover can be safely merged.  */
+-	      if (SMALL_REGISTER_CLASSES)
+-		merge_assigned_reloads (insn);
+-
+ 	      /* Generate the insns to reload operands into or out of
+ 		 their reload regs.  */
+ 	      emit_reload_insns (chain);
+@@ -6598,152 +6591,6 @@ deallocate_reload_reg (int r)
+   reload_spill_index[r] = -1;
+ }
+ 
+-/* If SMALL_REGISTER_CLASSES is nonzero, we may not have merged two
+-   reloads of the same item for fear that we might not have enough reload
+-   registers. However, normally they will get the same reload register
+-   and hence actually need not be loaded twice.
+-
+-   Here we check for the most common case of this phenomenon: when we have
+-   a number of reloads for the same object, each of which were allocated
+-   the same reload_reg_rtx, that reload_reg_rtx is not used for any other
+-   reload, and is not modified in the insn itself.  If we find such,
+-   merge all the reloads and set the resulting reload to RELOAD_OTHER.
+-   This will not increase the number of spill registers needed and will
+-   prevent redundant code.  */
+-
+-static void
+-merge_assigned_reloads (rtx insn)
+-{
+-  int i, j;
+-
+-  /* Scan all the reloads looking for ones that only load values and
+-     are not already RELOAD_OTHER and ones whose reload_reg_rtx are
+-     assigned and not modified by INSN.  */
+-
+-  for (i = 0; i < n_reloads; i++)
+-    {
+-      int conflicting_input = 0;
+-      int max_input_address_opnum = -1;
+-      int min_conflicting_input_opnum = MAX_RECOG_OPERANDS;
+-
+-      if (rld[i].in == 0 || rld[i].when_needed == RELOAD_OTHER
+-	  || rld[i].out != 0 || rld[i].reg_rtx == 0
+-	  || reg_set_p (rld[i].reg_rtx, insn))
+-	continue;
+-
+-      /* Look at all other reloads.  Ensure that the only use of this
+-	 reload_reg_rtx is in a reload that just loads the same value
+-	 as we do.  Note that any secondary reloads must be of the identical
+-	 class since the values, modes, and result registers are the
+-	 same, so we need not do anything with any secondary reloads.  */
+-
+-      for (j = 0; j < n_reloads; j++)
+-	{
+-	  if (i == j || rld[j].reg_rtx == 0
+-	      || ! reg_overlap_mentioned_p (rld[j].reg_rtx,
+-					    rld[i].reg_rtx))
+-	    continue;
+-
+-	  if (rld[j].when_needed == RELOAD_FOR_INPUT_ADDRESS
+-	      && rld[j].opnum > max_input_address_opnum)
+-	    max_input_address_opnum = rld[j].opnum;
+-
+-	  /* If the reload regs aren't exactly the same (e.g, different modes)
+-	     or if the values are different, we can't merge this reload.
+-	     But if it is an input reload, we might still merge
+-	     RELOAD_FOR_INPUT_ADDRESS and RELOAD_FOR_OTHER_ADDRESS reloads.  */
+-
+-	  if (! rtx_equal_p (rld[i].reg_rtx, rld[j].reg_rtx)
+-	      || rld[j].out != 0 || rld[j].in == 0
+-	      || ! rtx_equal_p (rld[i].in, rld[j].in))
+-	    {
+-	      if (rld[j].when_needed != RELOAD_FOR_INPUT
+-		  || ((rld[i].when_needed != RELOAD_FOR_INPUT_ADDRESS
+-		       || rld[i].opnum > rld[j].opnum)
+-		      && rld[i].when_needed != RELOAD_FOR_OTHER_ADDRESS))
+-		break;
+-	      conflicting_input = 1;
+-	      if (min_conflicting_input_opnum > rld[j].opnum)
+-		min_conflicting_input_opnum = rld[j].opnum;
+-	    }
+-	}
+-
+-      /* If all is OK, merge the reloads.  Only set this to RELOAD_OTHER if
+-	 we, in fact, found any matching reloads.  */
+-
+-      if (j == n_reloads
+-	  && max_input_address_opnum <= min_conflicting_input_opnum)
+-	{
+-	  gcc_assert (rld[i].when_needed != RELOAD_FOR_OUTPUT);
+-
+-	  for (j = 0; j < n_reloads; j++)
+-	    if (i != j && rld[j].reg_rtx != 0
+-		&& rtx_equal_p (rld[i].reg_rtx, rld[j].reg_rtx)
+-		&& (! conflicting_input
+-		    || rld[j].when_needed == RELOAD_FOR_INPUT_ADDRESS
+-		    || rld[j].when_needed == RELOAD_FOR_OTHER_ADDRESS))
+-	      {
+-		rld[i].when_needed = RELOAD_OTHER;
+-		rld[j].in = 0;
+-		reload_spill_index[j] = -1;
+-		transfer_replacements (i, j);
+-	      }
+-
+-	  /* If this is now RELOAD_OTHER, look for any reloads that
+-	     load parts of this operand and set them to
+-	     RELOAD_FOR_OTHER_ADDRESS if they were for inputs,
+-	     RELOAD_OTHER for outputs.  Note that this test is
+-	     equivalent to looking for reloads for this operand
+-	     number.
+-
+-	     We must take special care with RELOAD_FOR_OUTPUT_ADDRESS;
+-	     it may share registers with a RELOAD_FOR_INPUT, so we can
+-	     not change it to RELOAD_FOR_OTHER_ADDRESS.  We should
+-	     never need to, since we do not modify RELOAD_FOR_OUTPUT.
+-
+-	     It is possible that the RELOAD_FOR_OPERAND_ADDRESS
+-	     instruction is assigned the same register as the earlier
+-	     RELOAD_FOR_OTHER_ADDRESS instruction.  Merging these two
+-	     instructions will cause the RELOAD_FOR_OTHER_ADDRESS
+-	     instruction to be deleted later on.  */
+-
+-	  if (rld[i].when_needed == RELOAD_OTHER)
+-	    for (j = 0; j < n_reloads; j++)
+-	      if (rld[j].in != 0
+-		  && rld[j].when_needed != RELOAD_OTHER
+-		  && rld[j].when_needed != RELOAD_FOR_OTHER_ADDRESS
+-		  && rld[j].when_needed != RELOAD_FOR_OUTPUT_ADDRESS
+-		  && rld[j].when_needed != RELOAD_FOR_OPERAND_ADDRESS
+-		  && (! conflicting_input
+-		      || rld[j].when_needed == RELOAD_FOR_INPUT_ADDRESS
+-		      || rld[j].when_needed == RELOAD_FOR_INPADDR_ADDRESS)
+-		  && reg_overlap_mentioned_for_reload_p (rld[j].in,
+-							 rld[i].in))
+-		{
+-		  int k;
+-
+-		  rld[j].when_needed
+-		    = ((rld[j].when_needed == RELOAD_FOR_INPUT_ADDRESS
+-			|| rld[j].when_needed == RELOAD_FOR_INPADDR_ADDRESS)
+-		       ? RELOAD_FOR_OTHER_ADDRESS : RELOAD_OTHER);
+-
+-		  /* Check to see if we accidentally converted two
+-		     reloads that use the same reload register with
+-		     different inputs to the same type.  If so, the
+-		     resulting code won't work.  */
+-		  if (rld[j].reg_rtx)
+-		    for (k = 0; k < j; k++)
+-		      gcc_assert (rld[k].in == 0 || rld[k].reg_rtx == 0
+-				  || rld[k].when_needed != rld[j].when_needed
+-				  || !rtx_equal_p (rld[k].reg_rtx,
+-						   rld[j].reg_rtx)
+-				  || rtx_equal_p (rld[k].in,
+-						  rld[j].in));
+-		}
+-	}
+-    }
+-}
+-
+ /* These arrays are filled by emit_reload_insns and its subroutines.  */
+ static rtx input_reload_insns[MAX_RECOG_OPERANDS];
+ static rtx other_input_address_reload_insns = 0;
diff --git a/4.4.4/gentoo/README.history b/4.4.4/gentoo/README.history
index 25c798f..e421289 100644
--- a/4.4.4/gentoo/README.history
+++ b/4.4.4/gentoo/README.history
@@ -1,3 +1,4 @@
+	+ 50_all_pr45312-kernel-miscompile.patch
 	+ 62_all_ia64-pr41551.patch
 	+ 96_all_arm-pr43440.patch