From 37b0c0c107be5a66e933f54befeb9eb22e4d072b Mon Sep 17 00:00:00 2001
From: nickc <nickc@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Tue, 10 May 2011 10:34:44 +0000
Subject: [PATCH] 	* config/rx/rx.h (JUMP_ALIGN, LABEL_ALIGN, LOOP_ALIGN): Define.
 	(LABEL_ALIGN_AFTER_BARRIER): Pass label to rx_align_for_label
 	* config/rx/rx.c (rx_align_for_label): Add label and
 	uses_threshold parameters.  Do not align when the label is not
 	used enough.
 	* config/rx/rx-protos.h (rx_align_for_label): Update prototype.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/gcc-4_6-branch@173613 138bc75d-0d04-0410-961f-82ee72b054a4

index e1ab9c2..8c8862e 100644
--- a/gcc/config/rx/rx-protos.h
+++ b/gcc/config/rx/rx-protos.h
@@ -30,7 +30,7 @@ extern void		rx_expand_prologue (void);
 extern int		rx_initial_elimination_offset (int, int);
 
 #ifdef RTX_CODE
-extern int 		rx_align_for_label (void);
+extern int 		rx_align_for_label (rtx, int);
 extern void             rx_emit_stack_popm (rtx *, bool);
 extern void             rx_emit_stack_pushm (rtx *);
 extern void		rx_expand_epilogue (bool);
@@ -38,7 +38,7 @@ extern char *		rx_gen_move_template (rtx *, bool);
 extern bool		rx_is_legitimate_constant (rtx);
 extern bool		rx_is_restricted_memory_address (rtx, Mmode);
 extern bool		rx_match_ccmode (rtx, Mmode);
-extern void		rx_notice_update_cc (rtx body, rtx insn);
+extern void		rx_notice_update_cc (rtx, rtx);
 extern void		rx_split_cbranch (Mmode, Rcode, rtx, rtx, rtx);
 extern Mmode		rx_select_cc_mode (Rcode, rtx, rtx);
 #endif
diff --git a/gcc/config/rx/rx.c b/gcc/config/rx/rx.c
index ad8d0bb..f56e779 100644
--- a/gcc/config/rx/rx.c
+++ b/gcc/config/rx/rx.c
@@ -2752,8 +2752,15 @@ rx_match_ccmode (rtx insn, enum machine_mode cc_mode)
 
 
 int
-rx_align_for_label (void)
+rx_align_for_label (rtx lab, int uses_threshold)
 {
+  /* This is a simple heuristic to guess when an alignment would not be useful
+     because the delay due to the inserted NOPs would be greater than the delay
+     due to the misaligned branch.  If uses_threshold is zero then the alignment
+     is always useful.  */
+  if (LABEL_NUSES (lab) < uses_threshold)
+    return 0;
+
   return optimize_size ? 1 : 3;
 }
 
diff --git a/gcc/config/rx/rx.h b/gcc/config/rx/rx.h
index 01fc23b..4a88a5b 100644
--- a/gcc/config/rx/rx.h
+++ b/gcc/config/rx/rx.h
@@ -617,7 +617,13 @@ typedef unsigned int CUMULATIVE_ARGS;
 
 #define SELECT_CC_MODE(OP,X,Y)  rx_select_cc_mode((OP), (X), (Y))
 
-#define LABEL_ALIGN_AFTER_BARRIER(x)		rx_align_for_label ()
+/* Compute the alignment needed for label X in various situations.
+   If the user has specified an alignment then honour that, otherwise
+   use rx_align_for_label.  */
+#define JUMP_ALIGN(x)				(align_jumps ? align_jumps : rx_align_for_label (x, 0))
+#define LABEL_ALIGN(x)				(align_labels ? align_labels : rx_align_for_label (x, 3))
+#define LOOP_ALIGN(x)				(align_loops ? align_loops : rx_align_for_label (x, 2))
+#define LABEL_ALIGN_AFTER_BARRIER(x)		rx_align_for_label (x, 0)
 
 #define ASM_OUTPUT_MAX_SKIP_ALIGN(STREAM, LOG, MAX_SKIP)	\
   do						\
-- 
1.7.0.4