Patchwork Improve handling of is_const_type && is_volatile_type in modified_type_die (PR debug/45997)

login
register
mail settings
Submitter Jakub Jelinek
Date Nov. 3, 2010, 5:44 p.m.
Message ID <20101103174436.GR29412@tyan-ft48-01.lab.bos.redhat.com>
Download mbox | patch
Permalink /patch/70042/
State New
Headers show

Comments

Jakub Jelinek - Nov. 3, 2010, 5:44 p.m.
Hi!

If both is_const_type and is_volatile_type are set, then we can either
choose to start with DW_TAG_const_type, or DW_TAG_volatile_type.
If we choose badly, we might end up with no qualified_type and an unnamed
DW_TAG_base_type.

The following patch fixes it by starting with DW_TAG_volatile_type if
starting DW_TAG_const_type would lead to no qualified_type, while
starting with DW_TAG_volatile_type works.

Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

2010-11-03  Jakub Jelinek  <jakub@redhat.com>

	PR debug/45997
	* dwarf2out.c (modified_type_die): If both is_const_type and
	is_volatile_type is set, start with DW_TAG_const_type or
	DW_TAG_volatile_type depending on where we get qualified type
	in the recursive call.

	* g++.dg/debug/dwarf2/pr45997-1.C: New test.
	* g++.dg/debug/dwarf2/pr45997-2.C: New test.


	Jakub

Patch

--- gcc/dwarf2out.c.jj	2010-11-01 09:07:22.000000000 +0100
+++ gcc/dwarf2out.c	2010-11-03 14:43:37.000000000 +0100
@@ -12764,7 +12764,12 @@  modified_type_die (tree type, int is_con
       /* Else cv-qualified version of named type; fall through.  */
     }
 
-  if (is_const_type)
+  if (is_const_type
+      /* If both is_const_type and is_volatile_type, prefer the path
+	 which leads to a qualified type.  */
+      && (!is_volatile_type
+	  || get_qualified_type (type, TYPE_QUAL_CONST) == NULL_TREE
+	  || get_qualified_type (type, TYPE_QUAL_VOLATILE) != NULL_TREE))
     {
       mod_type_die = new_die (DW_TAG_const_type, comp_unit_die (), type);
       sub_die = modified_type_die (type, 0, is_volatile_type, context_die);
@@ -12772,7 +12777,7 @@  modified_type_die (tree type, int is_con
   else if (is_volatile_type)
     {
       mod_type_die = new_die (DW_TAG_volatile_type, comp_unit_die (), type);
-      sub_die = modified_type_die (type, 0, 0, context_die);
+      sub_die = modified_type_die (type, is_const_type, 0, context_die);
     }
   else if (code == POINTER_TYPE)
     {
--- gcc/testsuite/g++.dg/debug/dwarf2/pr45997-1.C.jj	2010-11-03 14:55:58.000000000 +0100
+++ gcc/testsuite/g++.dg/debug/dwarf2/pr45997-1.C	2010-11-03 14:57:08.000000000 +0100
@@ -0,0 +1,22 @@ 
+// PR debug/45997
+// { dg-do compile }
+// { dg-options "-gdwarf-2 -dA" }
+
+typedef int my_int;
+typedef const my_int const_my_int;
+typedef volatile const_my_int volatile_const_my_int;
+
+my_int v_my_int = 0;
+const_my_int v_const_my_int = 1;
+volatile_const_my_int v_volatile_const_my_int = 4;
+
+int
+main ()
+{
+  asm volatile ("" : : "r" (&v_my_int));
+  asm volatile ("" : : "r" (&v_const_my_int));
+  asm volatile ("" : : "r" (&v_volatile_const_my_int));
+  return 0;
+}
+
+// { dg-final { scan-assembler-times "DIE\[^\n\r\]*DW_TAG_base_type" 1 } }
--- gcc/testsuite/g++.dg/debug/dwarf2/pr45997-2.C.jj	2010-11-03 14:55:58.000000000 +0100
+++ gcc/testsuite/g++.dg/debug/dwarf2/pr45997-2.C	2010-11-03 14:57:33.000000000 +0100
@@ -0,0 +1,22 @@ 
+// PR debug/45997
+// { dg-do compile }
+// { dg-options "-gdwarf-2 -dA" }
+
+typedef int my_int;
+typedef volatile my_int volatile_my_int;
+typedef const volatile_my_int const_volatile_my_int;
+
+my_int v_my_int = 0;
+volatile_my_int v_volatile_my_int = 1;
+const_volatile_my_int v_const_volatile_my_int = 4;
+
+int
+main ()
+{
+  asm volatile ("" : : "r" (&v_my_int));
+  asm volatile ("" : : "r" (&v_volatile_my_int));
+  asm volatile ("" : : "r" (&v_const_volatile_my_int));
+  return 0;
+}
+
+// { dg-final { scan-assembler-times "DIE\[^\n\r\]*DW_TAG_base_type" 1 } }