When removing the MEM_ATTR unification hash I didn't grep for
MEM_ATTR equality comares which now causes PR61672, missed
optimizations at least in PRE. The following fixes that by
exporting and using mem_attrs_eq_p.
Bootstrapped and tested on x86_64-unknown-linux-gnu - as this is
a regression on the 4.9 branch I'd like to eventually backport this.
Richard.
2014-08-05 Richard Biener <rguent...@suse.de>
PR rtl-optimization/61672
* emit-rtl.h (mem_attrs_eq_p): Declare.
* emit-rtl.c (mem_attrs_eq_p): Export. Handle NULL mem-attrs.
* cse.c (exp_equiv_p): Use mem_attrs_eq_p.
* cfgcleanup.c (merge_memattrs): Likewise.
Include emit-rtl.h.
Index: gcc/emit-rtl.h
===================================================================
--- gcc/emit-rtl.h (revision 208113)
+++ gcc/emit-rtl.h (working copy)
@@ -20,6 +20,9 @@ along with GCC; see the file COPYING3.
#ifndef GCC_EMIT_RTL_H
#define GCC_EMIT_RTL_H
+/* Return whether two MEM_ATTRs are equal. */
+bool mem_attrs_eq_p (const struct mem_attrs *, const struct mem_attrs *);
+
/* Set the alias set of MEM to SET. */
extern void set_mem_alias_set (rtx, alias_set_type);
Index: gcc/emit-rtl.c
===================================================================
--- gcc/emit-rtl.c (revision 208113)
+++ gcc/emit-rtl.c (working copy)
@@ -245,9 +245,13 @@ const_fixed_htab_eq (const void *x, cons
/* Return true if the given memory attributes are equal. */
-static bool
+bool
mem_attrs_eq_p (const struct mem_attrs *p, const struct mem_attrs *q)
{
+ if (p == q)
+ return true;
+ if (!p || !q)
+ return false;
return (p->alias == q->alias
&& p->offset_known_p == q->offset_known_p
&& (!p->offset_known_p || p->offset == q->offset)
Index: gcc/cse.c
===================================================================
--- gcc/cse.c (revision 208113)
+++ gcc/cse.c (working copy)
@@ -2680,7 +2680,7 @@ exp_equiv_p (const_rtx x, const_rtx y, i
But because really all MEM attributes should be the same for
equivalent MEMs, we just use the invariant that MEMs that have
the same attributes share the same mem_attrs data structure. */
- if (MEM_ATTRS (x) != MEM_ATTRS (y))
+ if (!mem_attrs_eq_p (MEM_ATTRS (x), MEM_ATTRS (y)))
return 0;
}
break;
Index: gcc/cfgcleanup.c
===================================================================
--- gcc/cfgcleanup.c (revision 208113)
+++ gcc/cfgcleanup.c (working copy)
@@ -53,6 +53,7 @@ along with GCC; see the file COPYING3.
#include "df.h"
#include "dce.h"
#include "dbgcnt.h"
+#include "emit-rtl.h"
#define FORWARDER_BLOCK_P(BB) ((BB)->flags & BB_FORWARDER_BLOCK)
@@ -882,7 +883,7 @@ merge_memattrs (rtx x, rtx y)
if (GET_MODE (x) != GET_MODE (y))
return;
- if (code == MEM && MEM_ATTRS (x) != MEM_ATTRS (y))
+ if (code == MEM && !mem_attrs_eq_p (MEM_ATTRS (x), MEM_ATTRS (y)))
{
if (! MEM_ATTRS (x))
MEM_ATTRS (y) = 0;
