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Re: RFC: VTA alias set discrepancy
> While existing callers are under !DECL_RTL_SET_P it is not obvious
> that that is true here, so please add
>
> if (DECL_RTL_SET_P (decl))
> return DECL_RTL (decl);
Fixed.
> Please also adjust cfgexpand.c:expand_debug_expr (just see
> where we do SET_DECL_RTL (.., NULL)).
Fixed.
I also had to move the prototype for make_decl_rtl_for_debug into
tree.h, as cfgexpand.c does not include output.h.
I am (re)testing the patch below and will commit if there are no
regressions.
Thanks for the prompt reviews folks.
* tree.h: Declare make_decl_rtl_for_debug.
* varasm.c (make_decl_rtl_for_debug): New.
* dwarf2out.c (rtl_for_decl_location): Call it.
* cfgexpand.c (expand_debug_expr): Call it.
Index: tree.h
===================================================================
--- tree.h (revision 157481)
+++ tree.h (working copy)
@@ -5131,6 +5131,7 @@ extern unsigned int update_alignment_for
unsigned int);
/* varasm.c */
extern void make_decl_rtl (tree);
+extern rtx make_decl_rtl_for_debug (tree);
extern void make_decl_one_only (tree, tree);
extern int supports_one_only (void);
extern void resolve_unique_section (tree, int, int);
Index: testsuite/gfortran.dg/assign-debug.f90
===================================================================
--- testsuite/gfortran.dg/assign-debug.f90 (revision 0)
+++ testsuite/gfortran.dg/assign-debug.f90 (revision 0)
@@ -0,0 +1,8 @@
+! { dg-do compile }
+! { dg-options "-fcompare-debug -O2" }
+ program test
+ integer i
+ common i
+ assign 2000 to i ! { dg-warning "Deleted feature: ASSIGN statement" }
+2000 continue
+ end
Index: dwarf2out.c
===================================================================
--- dwarf2out.c (revision 157481)
+++ dwarf2out.c (working copy)
@@ -15770,10 +15770,7 @@ rtl_for_decl_location (tree decl)
&& !DECL_HARD_REGISTER (decl)
&& DECL_MODE (decl) != VOIDmode)
{
- rtl = DECL_RTL (decl);
- /* Reset DECL_RTL back, as various parts of the compiler expects
- DECL_RTL set meaning it is actually going to be output. */
- SET_DECL_RTL (decl, NULL);
+ rtl = make_decl_rtl_for_debug (decl);
if (!MEM_P (rtl)
|| GET_CODE (XEXP (rtl, 0)) != SYMBOL_REF
|| SYMBOL_REF_DECL (XEXP (rtl, 0)) != decl)
Index: cfgexpand.c
===================================================================
--- cfgexpand.c (revision 157481)
+++ cfgexpand.c (working copy)
@@ -2339,8 +2339,7 @@ expand_debug_expr (tree exp)
|| mode == VOIDmode)
return NULL;
- op0 = DECL_RTL (exp);
- SET_DECL_RTL (exp, NULL);
+ op0 = make_decl_rtl_for_debug (exp);
if (!MEM_P (op0)
|| GET_CODE (XEXP (op0, 0)) != SYMBOL_REF
|| SYMBOL_REF_DECL (XEXP (op0, 0)) != exp)
Index: varasm.c
===================================================================
--- varasm.c (revision 157481)
+++ varasm.c (working copy)
@@ -1476,6 +1476,38 @@ make_decl_rtl (tree decl)
if (flag_mudflap && TREE_CODE (decl) == VAR_DECL)
mudflap_enqueue_decl (decl);
}
+
+/* Like make_decl_rtl, but inhibit creation of new alias sets when
+ calling make_decl_rtl. Also, reset DECL_RTL before returning the
+ rtl. */
+
+rtx
+make_decl_rtl_for_debug (tree decl)
+{
+ unsigned int save_aliasing_flag;
+ rtx rtl;
+
+ if (DECL_RTL_SET_P (decl))
+ return DECL_RTL (decl);
+
+ /* Kludge alert! Somewhere down the call chain, make_decl_rtl will
+ call new_alias_set. If running with -fcompare-debug, sometimes
+ we do not want to create alias sets that will throw the alias
+ numbers off in the comparison dumps. So... clearing
+ flag_strict_aliasing will keep new_alias_set() from creating a
+ new set. */
+ save_aliasing_flag = flag_strict_aliasing;
+ flag_strict_aliasing = 0;
+
+ rtl = DECL_RTL (decl);
+ /* Reset DECL_RTL back, as various parts of the compiler expects
+ DECL_RTL set meaning it is actually going to be output. */
+ SET_DECL_RTL (decl, NULL);
+
+ flag_strict_aliasing = save_aliasing_flag;
+
+ return rtl;
+}
/* Output a string of literal assembler code
for an `asm' keyword used between functions. */