From 944258ebc661d4e3ade20c12dfa5ae5101b87db4 Mon Sep 17 00:00:00 2001
From: Richard Sandiford <rdsandiford@googlemail.com>
Date: Mon, 6 Oct 2008 19:08:04 +0000
Subject: [PATCH] rs6000-protos.h (rs6000_find_base_term): Declare.

gcc/
	* config/rs6000/rs6000-protos.h (rs6000_find_base_term): Declare.
	* config/rs6000/rs6000.h (FIND_BASE_TERM): New macro.
	* config/rs6000/rs6000.c (rs6000_find_base_term): New function.

From-SVN: r140912
---
 gcc/ChangeLog                     |  6 ++++++
 gcc/config/rs6000/rs6000-protos.h |  1 +
 gcc/config/rs6000/rs6000.c        | 21 +++++++++++++++++++++
 gcc/config/rs6000/rs6000.h        |  2 ++
 4 files changed, 30 insertions(+)

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index e5af008102e..cbafd381198 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2008-10-06  Richard Sandiford  <rdsandiford@googlemail.com>
+
+	* config/rs6000/rs6000-protos.h (rs6000_find_base_term): Declare.
+	* config/rs6000/rs6000.h (FIND_BASE_TERM): New macro.
+	* config/rs6000/rs6000.c (rs6000_find_base_term): New function.
+
 2008-10-06  Richard Sandiford  <rdsandiford@googlemail.com>
 
 	* config/darwin-protos.h (machopic_function_base_name): Delete.
diff --git a/gcc/config/rs6000/rs6000-protos.h b/gcc/config/rs6000/rs6000-protos.h
index 42e939bf741..13e7becc526 100644
--- a/gcc/config/rs6000/rs6000-protos.h
+++ b/gcc/config/rs6000/rs6000-protos.h
@@ -112,6 +112,7 @@ extern rtx rs6000_legitimize_reload_address (rtx, enum machine_mode,
 extern int rs6000_legitimate_address (enum machine_mode, rtx, int);
 extern bool rs6000_legitimate_offset_address_p (enum machine_mode, rtx, int);
 extern bool rs6000_mode_dependent_address (rtx);
+extern rtx rs6000_find_base_term (rtx);
 extern bool rs6000_offsettable_memref_p (rtx);
 extern rtx rs6000_return_addr (int, rtx);
 extern void rs6000_output_symbol_ref (FILE*, rtx);
diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index 83a2753eb90..9f48b611e6f 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -4455,6 +4455,27 @@ rs6000_mode_dependent_address (rtx addr)
   return false;
 }
 
+/* Implement FIND_BASE_TERM.  */
+
+rtx
+rs6000_find_base_term (rtx op)
+{
+  rtx base, offset;
+
+  split_const (op, &base, &offset);
+  if (GET_CODE (base) == UNSPEC)
+    switch (XINT (base, 1))
+      {
+      case UNSPEC_TOCREL:
+      case UNSPEC_MACHOPIC_OFFSET:
+	/* OP represents SYM [+ OFFSET] - ANCHOR.  SYM is the base term
+	   for aliasing purposes.  */
+	return XVECEXP (base, 0, 0);
+      }
+
+  return op;
+}
+
 /* More elaborate version of recog's offsettable_memref_p predicate
    that works around the ??? note of rs6000_mode_dependent_address.
    In particular it accepts
diff --git a/gcc/config/rs6000/rs6000.h b/gcc/config/rs6000/rs6000.h
index 79250c87b07..39fc0f6c9b6 100644
--- a/gcc/config/rs6000/rs6000.h
+++ b/gcc/config/rs6000/rs6000.h
@@ -1856,6 +1856,8 @@ do {								\
   if (rs6000_mode_dependent_address (ADDR))			\
     goto LABEL;							\
 } while (0)
+
+#define FIND_BASE_TERM rs6000_find_base_term
 
 /* The register number of the register used to address a table of
    static data addresses in memory.  In some cases this register is