From 366f945f9bc15d885af5a20ed70547e96b2dafae Mon Sep 17 00:00:00 2001
From: Richard Guenther <rguenther@suse.de>
Date: Wed, 7 Apr 2010 10:14:17 +0000
Subject: [PATCH] re PR rtl-optimization/42617 (TARGET_MEM_REF and plain
INDIRECT_REFs are not handled by the RTL oracle)
2010-04-07 Richard Guenther <rguenther@suse.de>
PR middle-end/42617
* alias.c (ao_ref_from_mem): Without MEM_OFFSET or MEM_SIZE
preserve points-to related information.
From-SVN: r158046
---
gcc/ChangeLog | 6 ++++++
gcc/alias.c | 27 +++++++++++++++++----------
2 files changed, 23 insertions(+), 10 deletions(-)
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index d41b7d504b65..4c9b75ac9b9a 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2010-04-07 Richard Guenther <rguenther@suse.de>
+
+ PR middle-end/42617
+ * alias.c (ao_ref_from_mem): Without MEM_OFFSET or MEM_SIZE
+ preserve points-to related information.
+
2010-04-07 Richard Guenther <rguenther@suse.de>
PR middle-end/42617
diff --git a/gcc/alias.c b/gcc/alias.c
index cd7e2a06bdbb..19a8292b454f 100644
--- a/gcc/alias.c
+++ b/gcc/alias.c
@@ -265,11 +265,6 @@ ao_ref_from_mem (ao_ref *ref, const_rtx mem)
if (!expr)
return false;
- /* If MEM_OFFSET or MEM_SIZE are NULL punt. */
- if (!MEM_OFFSET (mem)
- || !MEM_SIZE (mem))
- return false;
-
ao_ref_init (ref, expr);
/* Get the base of the reference and see if we have to reject or
@@ -278,17 +273,17 @@ ao_ref_from_mem (ao_ref *ref, const_rtx mem)
if (base == NULL_TREE)
return false;
+ /* The tree oracle doesn't like to have these. */
+ if (TREE_CODE (base) == FUNCTION_DECL
+ || TREE_CODE (base) == LABEL_DECL)
+ return false;
+
/* If this is a pointer dereference of a non-SSA_NAME punt.
??? We could replace it with a pointer to anything. */
if (INDIRECT_REF_P (base)
&& TREE_CODE (TREE_OPERAND (base, 0)) != SSA_NAME)
return false;
- /* The tree oracle doesn't like to have these. */
- if (TREE_CODE (base) == FUNCTION_DECL
- || TREE_CODE (base) == LABEL_DECL)
- return false;
-
/* If this is a reference based on a partitioned decl replace the
base with an INDIRECT_REF of the pointer representative we
created during stack slot partitioning. */
@@ -307,6 +302,18 @@ ao_ref_from_mem (ao_ref *ref, const_rtx mem)
ref->ref_alias_set = MEM_ALIAS_SET (mem);
+ /* If MEM_OFFSET or MEM_SIZE are NULL we have to punt.
+ Keep points-to related information though. */
+ if (!MEM_OFFSET (mem)
+ || !MEM_SIZE (mem))
+ {
+ ref->ref = NULL_TREE;
+ ref->offset = 0;
+ ref->size = -1;
+ ref->max_size = -1;
+ return true;
+ }
+
/* If the base decl is a parameter we can have negative MEM_OFFSET in
case of promoted subregs on bigendian targets. Trust the MEM_EXPR
here. */
--
GitLab