[PATCH] Don't mark set of vDRAP from DRAP as frame related (PR debug/43290)

[Jakub Jelinek]

On Wed, Mar 10, 2010 at 08:10:10AM -0800, Richard Henderson wrote:
> On 03/10/2010 03:03 AM, Jakub Jelinek wrote:
> > 	PR debug/43290
> > 	* reg-notes.def (REG_CFA_SET_VDRAP): New note.
> > 	* dwarf2out.c (dwarf2out_frame_debug_expr): Remove rule 20 - setting
> > 	of fde->vdrap_reg.
> > 	(dwarf2out_frame_debug): Handle REG_CFA_SET_VDRAP note.
> > 	(based_loc_descr): Only express drap or vdrap regno based expressions
> > 	using DW_OP_fbreg when not optimizing.
> > 	* config/i386/i386.c (ix86_get_drap_rtx): When not optimizing,
> > 	make the vDRAP = DRAP assignment RTX_FRAME_RELATED_P and add
> > 	REG_CFA_SET_VDRAP note.
> > 
> > 	PR debug/36728
> > 	* gcc.dg/guality/pr36728-1.c: New test.
> > 	* gcc.dg/guality/pr36728-2.c: New test.
> 
> Ok.  Thanks for the test cases.

Oops, another follow-up.  Apparently (seen on a bunch of libgomp.c++
testcase in 4.4-RH backport of the patch, but the trunk has the same issue
latent) even when expand_stack_alignment thinks stack realignment might
be needed and thus does crtl->args.internal_arg_pointer = drap_rtx;
(and the computation of drap_rtx created vDRAP = DRAP insn with
REG_CFA_SET_VDRAP note), if reload didn't actually reload anything which
needs the larger alignment to the stack, ix86_expand_prologue
and ix86_finalize_stack_realign_flags in it might decide not to realign
the stack in the end.  Thus fde->drap_rtx is NULL and the REG_CFA_SET_VDRAP
handling code ICEs.  Apparently we want to set vdrap_reg even in that case
and replace it in based_loc_descr though, as crtl->args.internal_arg_pointer
is still that vDRAP register and thus is used as base of DECL_RTL of
parameters.

Ok for trunk?

2010-03-14  Jakub Jelinek  <jakub@redhat.com>

	* dwarf2out.c (dwarf2out_frame_debug): Don't assert drap_reg
	has been set.
	(based_loc_descr): Use DW_OP_fbreg for vdrap_reg even when
	drap_reg has not been set.

--- gcc/dwarf2out.c.jj	2010-03-12 14:05:32.000000000 +0100
+++ gcc/dwarf2out.c	2010-03-14 21:24:23.000000000 +0100
@@ -2760,11 +2760,12 @@ dwarf2out_frame_debug (rtx insn, bool af
 	if (REG_P (n))
 	  {
 	    dw_fde_ref fde = current_fde ();
-	    gcc_assert (fde
-			&& fde->drap_reg != INVALID_REGNUM
-			&& fde->vdrap_reg == INVALID_REGNUM);
-	    if (REG_P (n))
-	      fde->vdrap_reg = REGNO (n);
+	    if (fde)
+	      {
+		gcc_assert (fde->vdrap_reg == INVALID_REGNUM);
+		if (REG_P (n))
+		  fde->vdrap_reg = REGNO (n);
+	      }
 	  }
 	handled_one = true;
 	break;
@@ -12726,7 +12727,6 @@ based_loc_descr (rtx reg, HOST_WIDE_INT 
     }
   else if (!optimize
 	   && fde
-	   && fde->drap_reg != INVALID_REGNUM
 	   && (fde->drap_reg == REGNO (reg)
 	       || fde->vdrap_reg == REGNO (reg)))
     {


	Jakub