xtensa.c (xtensa_expand_prologue): Put a REG_FRAME_RELATED_EXPR note on the last…

xtensa.c (xtensa_expand_prologue): Put a REG_FRAME_RELATED_EXPR note on the last insn that sets up the stack...

	* config/xtensa/xtensa.c (xtensa_expand_prologue): Put a
	REG_FRAME_RELATED_EXPR note on the last insn that sets up the stack
	pointer or frame pointer.
	* config/xtensa/xtensa.h (DWARF_UNWIND_INFO): Delete.
	(MUST_USE_SJLJ_EXCEPTIONS): Define.
	(DWARF2_UNWIND_INFO): Define.
	(INCOMING_RETURN_ADDR_RTX): Define.
	(DWARF_FRAME_RETURN_COLUMN): Define.

From-SVN: r129854

gcc/ChangeLog

+2007-11-02  Bob Wilson  <bob.wilson@acm.org>
+
+	* config/xtensa/xtensa.c (xtensa_expand_prologue): Put a
+	REG_FRAME_RELATED_EXPR note on the last insn that sets up the stack
+	pointer or frame pointer.
+	* config/xtensa/xtensa.h (DWARF_UNWIND_INFO): Delete.
+	(MUST_USE_SJLJ_EXCEPTIONS): Define.
+	(DWARF2_UNWIND_INFO): Define.
+	(INCOMING_RETURN_ADDR_RTX): Define.
+	(DWARF_FRAME_RETURN_COLUMN): Define.
+
 2007-11-02  Tom Tromey  <tromey@redhat.com>
 
 	* varpool.c (dump_varpool): Use 'next', not 'next_needed' when

gcc/config/xtensa/xtensa.c

@@ -2305,12 +2305,13 @@ xtensa_expand_prologue (void)
 {
   HOST_WIDE_INT total_size;
   rtx size_rtx;
+  rtx insn, note_rtx;
 
   total_size = compute_frame_size (get_frame_size ());
   size_rtx = GEN_INT (total_size);
 
   if (total_size < (1 << (12+3)))
-    emit_insn (gen_entry (size_rtx, size_rtx));
+    insn = emit_insn (gen_entry (size_rtx, size_rtx));
   else
     {
       /* Use a8 as a temporary since a0-a7 may be live.  */
@@ -2318,14 +2319,14 @@ xtensa_expand_prologue (void)
       emit_insn (gen_entry (size_rtx, GEN_INT (MIN_FRAME_SIZE)));
       emit_move_insn (tmp_reg, GEN_INT (total_size - MIN_FRAME_SIZE));
       emit_insn (gen_subsi3 (tmp_reg, stack_pointer_rtx, tmp_reg));
-      emit_move_insn (stack_pointer_rtx, tmp_reg);
+      insn = emit_insn (gen_movsi (stack_pointer_rtx, tmp_reg));
     }
 
   if (frame_pointer_needed)
     {
       if (cfun->machine->set_frame_ptr_insn)
 	{
-	  rtx first, insn;
+	  rtx first;
 
 	  push_topmost_sequence ();
 	  first = get_insns ();
@@ -2347,8 +2348,20 @@ xtensa_expand_prologue (void)
 	    }
 	}
       else
-	emit_move_insn (hard_frame_pointer_rtx, stack_pointer_rtx);
-    }
+	insn = emit_insn (gen_movsi (hard_frame_pointer_rtx,
+				     stack_pointer_rtx));
+    }
+
+  /* Create a note to describe the CFA.  Because this is only used to set
+     DW_AT_frame_base for debug info, don't bother tracking changes through
+     each instruction in the prologue.  It just takes up space.  */
+  note_rtx = gen_rtx_SET (VOIDmode, (frame_pointer_needed
+				     ? hard_frame_pointer_rtx
+				     : stack_pointer_rtx),
+			  plus_constant (stack_pointer_rtx, -total_size));
+  RTX_FRAME_RELATED_P (insn) = 1;
+  REG_NOTES (insn) = gen_rtx_EXPR_LIST (REG_FRAME_RELATED_EXPR,
+					note_rtx, REG_NOTES (insn));
 }
 
 

gcc/config/xtensa/xtensa.h

@@ -1062,8 +1062,12 @@ typedef struct xtensa_args
 /* How to start an assembler comment.  */
 #define ASM_COMMENT_START "#"
 
-/* Exception handling TODO!! */
-#define DWARF_UNWIND_INFO 0
+/* Generate DWARF2 unwind info to get the DW_AT_frame_base set correctly,
+   even though we don't yet use it for unwinding.  */
+#define MUST_USE_SJLJ_EXCEPTIONS 1
+#define DWARF2_UNWIND_INFO 1
+#define INCOMING_RETURN_ADDR_RTX gen_rtx_REG (Pmode, 0)
+#define DWARF_FRAME_RETURN_COLUMN DWARF_FRAME_REGNUM (0)
 
 /* Xtensa constant pool breaks the devices in crtstuff.c to control
    section in where code resides.  We have to write it as asm code.  Use