From: Roger Sayle <roger@eyesopen.com>
Date: Tue, 28 Jan 2003 14:52:07 +0000 (+0000)
Subject: * cse.c (cse_insn): Avoid redundant REG_EQUAL notes.
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=a77b7e32ec72dc7ee6085cfe0cf29b4384c70b1e;p=gcc.git

* cse.c (cse_insn): Avoid redundant REG_EQUAL notes.

From-SVN: r61971
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 2fcc66f83cc..626823b06f3 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,7 @@
+2003-01-28  Roger Sayle  <roger@eyesopen.com>
+
+	* cse.c (cse_insn): Avoid redundant REG_EQUAL notes.
+
 2003-01-28  Richard Sandiford  <rsandifo@redhat.com>
 
 	* config/sh/sh.h (CLASS_MAX_NREGS): If TARGET_SHMEDIA, and the given
diff --git a/gcc/cse.c b/gcc/cse.c
index 84210babcbd..e396042111e 100644
--- a/gcc/cse.c
+++ b/gcc/cse.c
@@ -5684,12 +5684,16 @@ cse_insn (insn, libcall_insn)
 		&& GET_CODE (XEXP (XEXP (src_const, 0), 0)) == LABEL_REF
 		&& GET_CODE (XEXP (XEXP (src_const, 0), 1)) == LABEL_REF))
 	{
-	  /* Make sure that the rtx is not shared with any other insn.  */
-	  src_const = copy_rtx (src_const);
+	  /* We only want a REG_EQUAL note if src_const != src.  */
+	  if (! rtx_equal_p (src, src_const))
+	    {
+	      /* Make sure that the rtx is not shared.  */
+	      src_const = copy_rtx (src_const);
 
-	  /* Record the actual constant value in a REG_EQUAL note, making
-	     a new one if one does not already exist.  */
-	  set_unique_reg_note (insn, REG_EQUAL, src_const);
+	      /* Record the actual constant value in a REG_EQUAL note,
+		 making a new one if one does not already exist.  */
+	      set_unique_reg_note (insn, REG_EQUAL, src_const);
+	    }
 
 	  /* If storing a constant value in a register that
 	     previously held the constant value 0,