PR rtl-optimization/39794

	* alias.c (canon_true_dependence): Add x_addr argument.
	* rtl.h (canon_true_dependence): Adjust prototype.
	* cse.c (check_dependence): Adjust canon_true_dependence callers.
	* cselib.c (cselib_invalidate_mem): Likewise.
	* gcse.c (compute_transp): Likewise.
	* dse.c (scan_reads_nospill): Likewise.
	(record_store, check_mem_read_rtx): Likewise.  For non-const-or-frame
	addresses pass base->val_rtx as mem_addr, for const-or-frame addresses
	canon_base_addr of the group, plus optional offset.
	(struct group_info): Rename canon_base_mem to
	canon_base_addr.
	(get_group_info): Set canon_base_addr to canon_rtx of base, not
	canon_rtx of base_mem.

	* gcc.dg/pr39794.c: New test.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@146669 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 5 insertions, 5 deletions

diff --git a/gcc/alias.c b/gcc/alias.c
index acfd934a7cf..8a20f467905 100644
--- a/gcc/alias.c
+++ b/gcc/alias.c
@@ -2287,14 +2287,13 @@ true_dependence (const_rtx mem, enum machine_mode mem_mode, const_rtx x,
    Variant of true_dependence which assumes MEM has already been
    canonicalized (hence we no longer do that here).
    The mem_addr argument has been added, since true_dependence computed
-   this value prior to canonicalizing.  */
+   this value prior to canonicalizing.
+   If x_addr is non-NULL, it is used in preference of XEXP (x, 0).  */
 
 int
 canon_true_dependence (const_rtx mem, enum machine_mode mem_mode, rtx mem_addr,
-		       const_rtx x, bool (*varies) (const_rtx, bool))
+		       const_rtx x, rtx x_addr, bool (*varies) (const_rtx, bool))
 {
-  rtx x_addr;
-
   if (MEM_VOLATILE_P (x) && MEM_VOLATILE_P (mem))
     return 1;
 
@@ -2320,7 +2319,8 @@ canon_true_dependence (const_rtx mem, enum machine_mode mem_mode, rtx mem_addr,
   if (nonoverlapping_memrefs_p (x, mem))
     return 0;
 
-  x_addr = get_addr (XEXP (x, 0));
+  if (! x_addr)
+    x_addr = get_addr (XEXP (x, 0));
 
   if (! base_alias_check (x_addr, mem_addr, GET_MODE (x), mem_mode))
     return 0;