gcc-5.3: backport fix for PR-target-65358

Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

2 files changed, 309 insertions, 1 deletions

diff --git a/meta/recipes-devtools/gcc/gcc-5.3.inc b/meta/recipes-devtools/gcc/gcc-5.3.inc
index a522bc40c2..a2e347adfe 100644
--- a/meta/recipes-devtools/gcc/gcc-5.3.inc
+++ b/meta/recipes-devtools/gcc/gcc-5.3.inc
@@ -82,7 +82,8 @@ SRC_URI = "\
            file://0050-powerpc-pass-secure-plt-to-the-linker.patch \
            file://0051-Ignore-fdebug-prefix-map-in-producer-string-by-Danie.patch \
            file://0052-nios2-use-ret-with-r31.patch \
-          "
+           file://0053-expr.c-PR-target-65358-Avoid-clobbering-partial-argu.patch \
+"
 
 BACKPORTS = ""
 
diff --git a/meta/recipes-devtools/gcc/gcc-5.3/0053-expr.c-PR-target-65358-Avoid-clobbering-partial-argu.patch b/meta/recipes-devtools/gcc/gcc-5.3/0053-expr.c-PR-target-65358-Avoid-clobbering-partial-argu.patch
new file mode 100644
index 0000000000..c18f40e740
--- /dev/null
+++ b/meta/recipes-devtools/gcc/gcc-5.3/0053-expr.c-PR-target-65358-Avoid-clobbering-partial-argu.patch
@@ -0,0 +1,307 @@
+From 536b8318974495cde2b42c3c2742748e2b271be0 Mon Sep 17 00:00:00 2001
+From: ktkachov <ktkachov@138bc75d-0d04-0410-961f-82ee72b054a4>
+Date: Wed, 27 May 2015 13:25:01 +0000
+Subject: [PATCH] PR target/65358 Avoid clobbering partial argument during
+ sibcall
+
+	PR target/65358
+	* expr.c (memory_load_overlap): New function.
+	(emit_push_insn): When pushing partial args to the stack would
+	clobber the register part load the overlapping part into a pseudo
+	and put it into the hard reg after pushing.  Change return type
+	to bool.  Add bool argument.
+	* expr.h (emit_push_insn): Change return type to bool.
+	Add bool argument.
+	* calls.c (expand_call): Cancel sibcall optimization when encountering
+	partial argument on targets with ARGS_GROW_DOWNWARD and
+	!STACK_GROWS_DOWNWARD.
+	(emit_library_call_value_1): Update callsite of emit_push_insn.
+	(store_one_arg): Likewise.
+
+	PR target/65358
+	* gcc.dg/pr65358.c: New test.
+
+git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@223753 138bc75d-0d04-0410-961f-82ee72b054a4
+
+Upstream-Status: Backport from 6.0
+Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>
+---
+ gcc/calls.c                    | 17 ++++++--
+ gcc/expr.c                     | 90 +++++++++++++++++++++++++++++++++++++-----
+ gcc/expr.h                     |  4 +-
+ gcc/testsuite/gcc.dg/pr65358.c | 33 ++++++++++++++++
+ 4 files changed, 129 insertions(+), 15 deletions(-)
+ create mode 100644 gcc/testsuite/gcc.dg/pr65358.c
+
+diff --git a/gcc/calls.c b/gcc/calls.c
+index ee8ea5f..2334381 100644
+--- a/gcc/calls.c
++++ b/gcc/calls.c
+@@ -3236,6 +3236,14 @@ expand_call (tree exp, rtx target, int ignore)
+ 	    {
+ 	      rtx_insn *before_arg = get_last_insn ();
+ 
++	     /* On targets with weird calling conventions (e.g. PA) it's
++		hard to ensure that all cases of argument overlap between
++		stack and registers work.  Play it safe and bail out.  */
++#if defined(ARGS_GROW_DOWNWARD) && !defined(STACK_GROWS_DOWNWARD)
++		  sibcall_failure = 1;
++		  break;
++#endif
++
+ 	      if (store_one_arg (&args[i], argblock, flags,
+ 				 adjusted_args_size.var != 0,
+ 				 reg_parm_stack_space)
+@@ -4279,7 +4287,7 @@ emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
+ 			  partial, reg, 0, argblock,
+ 			  GEN_INT (argvec[argnum].locate.offset.constant),
+ 			  reg_parm_stack_space,
+-			  ARGS_SIZE_RTX (argvec[argnum].locate.alignment_pad));
++			  ARGS_SIZE_RTX (argvec[argnum].locate.alignment_pad), false);
+ 
+ 	  /* Now mark the segment we just used.  */
+ 	  if (ACCUMULATE_OUTGOING_ARGS)
+@@ -4886,10 +4894,11 @@ store_one_arg (struct arg_data *arg, rtx argblock, int flags,
+ 
+       /* This isn't already where we want it on the stack, so put it there.
+ 	 This can either be done with push or copy insns.  */
+-      emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
++      if (!emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
+ 		      parm_align, partial, reg, used - size, argblock,
+ 		      ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
+-		      ARGS_SIZE_RTX (arg->locate.alignment_pad));
++		      ARGS_SIZE_RTX (arg->locate.alignment_pad), true))
++	sibcall_failure = 1;
+ 
+       /* Unless this is a partially-in-register argument, the argument is now
+ 	 in the stack.  */
+@@ -5001,7 +5010,7 @@ store_one_arg (struct arg_data *arg, rtx argblock, int flags,
+       emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
+ 		      parm_align, partial, reg, excess, argblock,
+ 		      ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
+-		      ARGS_SIZE_RTX (arg->locate.alignment_pad));
++		      ARGS_SIZE_RTX (arg->locate.alignment_pad), false);
+ 
+       /* Unless this is a partially-in-register argument, the argument is now
+ 	 in the stack.
+diff --git a/gcc/expr.c b/gcc/expr.c
+index 5c09550..24a6293 100644
+--- a/gcc/expr.c
++++ b/gcc/expr.c
+@@ -4121,12 +4121,35 @@ emit_single_push_insn (machine_mode mode, rtx x, tree type)
+ }
+ #endif
+ 
++/* If reading SIZE bytes from X will end up reading from
++   Y return the number of bytes that overlap.  Return -1
++   if there is no overlap or -2 if we can't determine
++   (for example when X and Y have different base registers).  */
++
++static int
++memory_load_overlap (rtx x, rtx y, HOST_WIDE_INT size)
++{
++  rtx tmp = plus_constant (Pmode, x, size);
++  rtx sub = simplify_gen_binary (MINUS, Pmode, tmp, y);
++
++  if (!CONST_INT_P (sub))
++    return -2;
++
++  HOST_WIDE_INT val = INTVAL (sub);
++
++  return IN_RANGE (val, 1, size) ? val : -1;
++}
++
+ /* Generate code to push X onto the stack, assuming it has mode MODE and
+    type TYPE.
+    MODE is redundant except when X is a CONST_INT (since they don't
+    carry mode info).
+    SIZE is an rtx for the size of data to be copied (in bytes),
+    needed only if X is BLKmode.
++   Return true if successful.  May return false if asked to push a
++   partial argument during a sibcall optimization (as specified by
++   SIBCALL_P) and the incoming and outgoing pointers cannot be shown
++   to not overlap.
+ 
+    ALIGN (in bits) is maximum alignment we can assume.
+ 
+@@ -4152,11 +4175,11 @@ emit_single_push_insn (machine_mode mode, rtx x, tree type)
+    for arguments passed in registers.  If nonzero, it will be the number
+    of bytes required.  */
+ 
+-void
++bool
+ emit_push_insn (rtx x, machine_mode mode, tree type, rtx size,
+ 		unsigned int align, int partial, rtx reg, int extra,
+ 		rtx args_addr, rtx args_so_far, int reg_parm_stack_space,
+-		rtx alignment_pad)
++		rtx alignment_pad, bool sibcall_p)
+ {
+   rtx xinner;
+   enum direction stack_direction
+@@ -4179,6 +4202,10 @@ emit_push_insn (rtx x, machine_mode mode, tree type, rtx size,
+ 
+   xinner = x;
+ 
++  int nregs = partial / UNITS_PER_WORD;
++  rtx *tmp_regs = NULL;
++  int overlapping = 0;
++
+   if (mode == BLKmode
+       || (STRICT_ALIGNMENT && align < GET_MODE_ALIGNMENT (mode)))
+     {
+@@ -4309,6 +4336,43 @@ emit_push_insn (rtx x, machine_mode mode, tree type, rtx size,
+ 	     PARM_BOUNDARY.  Assume the caller isn't lying.  */
+ 	  set_mem_align (target, align);
+ 
++	  /* If part should go in registers and pushing to that part would
++	     overwrite some of the values that need to go into regs, load the
++	     overlapping values into temporary pseudos to be moved into the hard
++	     regs at the end after the stack pushing has completed.
++	     We cannot load them directly into the hard regs here because
++	     they can be clobbered by the block move expansions.
++	     See PR 65358.  */
++
++	  if (partial > 0 && reg != 0 && mode == BLKmode
++	      && GET_CODE (reg) != PARALLEL)
++	    {
++	      overlapping = memory_load_overlap (XEXP (x, 0), temp, partial);
++	      if (overlapping > 0)
++	        {
++		  gcc_assert (overlapping % UNITS_PER_WORD == 0);
++		  overlapping /= UNITS_PER_WORD;
++
++		  tmp_regs = XALLOCAVEC (rtx, overlapping);
++
++		  for (int i = 0; i < overlapping; i++)
++		    tmp_regs[i] = gen_reg_rtx (word_mode);
++
++		  for (int i = 0; i < overlapping; i++)
++		    emit_move_insn (tmp_regs[i],
++				    operand_subword_force (target, i, mode));
++	        }
++	      else if (overlapping == -1)
++		overlapping = 0;
++	      /* Could not determine whether there is overlap.
++	         Fail the sibcall.  */
++	      else
++		{
++		  overlapping = 0;
++		  if (sibcall_p)
++		    return false;
++		}
++	    }
+ 	  emit_block_move (target, xinner, size, BLOCK_OP_CALL_PARM);
+ 	}
+     }
+@@ -4363,12 +4427,13 @@ emit_push_insn (rtx x, machine_mode mode, tree type, rtx size,
+ 	 has a size a multiple of a word.  */
+       for (i = size - 1; i >= not_stack; i--)
+ 	if (i >= not_stack + offset)
+-	  emit_push_insn (operand_subword_force (x, i, mode),
++	  if (!emit_push_insn (operand_subword_force (x, i, mode),
+ 			  word_mode, NULL_TREE, NULL_RTX, align, 0, NULL_RTX,
+ 			  0, args_addr,
+ 			  GEN_INT (args_offset + ((i - not_stack + skip)
+ 						  * UNITS_PER_WORD)),
+-			  reg_parm_stack_space, alignment_pad);
++			  reg_parm_stack_space, alignment_pad, sibcall_p))
++	    return false;
+     }
+   else
+     {
+@@ -4411,9 +4476,8 @@ emit_push_insn (rtx x, machine_mode mode, tree type, rtx size,
+ 	}
+     }
+ 
+-  /* If part should go in registers, copy that part
+-     into the appropriate registers.  Do this now, at the end,
+-     since mem-to-mem copies above may do function calls.  */
++  /* Move the partial arguments into the registers and any overlapping
++     values that we moved into the pseudos in tmp_regs.  */
+   if (partial > 0 && reg != 0)
+     {
+       /* Handle calls that pass values in multiple non-contiguous locations.
+@@ -4421,9 +4485,15 @@ emit_push_insn (rtx x, machine_mode mode, tree type, rtx size,
+       if (GET_CODE (reg) == PARALLEL)
+ 	emit_group_load (reg, x, type, -1);
+       else
+-	{
++        {
+ 	  gcc_assert (partial % UNITS_PER_WORD == 0);
+-	  move_block_to_reg (REGNO (reg), x, partial / UNITS_PER_WORD, mode);
++	  move_block_to_reg (REGNO (reg), x, nregs - overlapping, mode);
++
++	  for (int i = 0; i < overlapping; i++)
++	    emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg)
++						    + nregs - overlapping + i),
++			    tmp_regs[i]);
++
+ 	}
+     }
+ 
+@@ -4432,6 +4502,8 @@ emit_push_insn (rtx x, machine_mode mode, tree type, rtx size,
+ 
+   if (alignment_pad && args_addr == 0)
+     anti_adjust_stack (alignment_pad);
++
++  return true;
+ }
+ 
+ /* Return X if X can be used as a subtarget in a sequence of arithmetic
+diff --git a/gcc/expr.h b/gcc/expr.h
+index 867852e..5fcc13f 100644
+--- a/gcc/expr.h
++++ b/gcc/expr.h
+@@ -218,8 +218,8 @@ extern rtx emit_move_resolve_push (machine_mode, rtx);
+ extern rtx push_block (rtx, int, int);
+ 
+ /* Generate code to push something onto the stack, given its mode and type.  */
+-extern void emit_push_insn (rtx, machine_mode, tree, rtx, unsigned int,
+-			    int, rtx, int, rtx, rtx, int, rtx);
++extern bool emit_push_insn (rtx, machine_mode, tree, rtx, unsigned int,
++			    int, rtx, int, rtx, rtx, int, rtx, bool);
+ 
+ /* Expand an assignment that stores the value of FROM into TO.  */
+ extern void expand_assignment (tree, tree, bool);
+diff --git a/gcc/testsuite/gcc.dg/pr65358.c b/gcc/testsuite/gcc.dg/pr65358.c
+new file mode 100644
+index 0000000..ba89fd4
+--- /dev/null
++++ b/gcc/testsuite/gcc.dg/pr65358.c
+@@ -0,0 +1,33 @@
++/* { dg-do run } */
++/* { dg-options "-O2" } */
++
++struct pack
++{
++  int fine;
++  int victim;
++  int killer;
++};
++
++int __attribute__ ((__noinline__, __noclone__))
++bar (int a, int b, struct pack p)
++{
++  if (a != 20 || b != 30)
++    __builtin_abort ();
++  if (p.fine != 40 || p.victim != 50 || p.killer != 60)
++    __builtin_abort ();
++  return 0;
++}
++
++int __attribute__ ((__noinline__, __noclone__))
++foo (int arg1, int arg2, int arg3, struct pack p)
++{
++  return bar (arg2, arg3, p);
++}
++
++int main (void)
++{
++  struct pack p = { 40, 50, 60 };
++
++  (void) foo (10, 20, 30, p);
++  return 0;
++}
+-- 
+2.7.0
+