From: kkojima <kkojima@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Thu, 16 Jul 2015 00:48:33 +0000 (+0000)
Subject: PR target/65249
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=d594fcbeeaa8bd8a555546b5672735af3ac0c308;p=thirdparty%2Fgcc.git

PR target/65249
* config/sh/sh.md (movdi): Split simple reg move to two movsi when
  the destination is R0 so as to lower R0-register pressure.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@225856 138bc75d-0d04-0410-961f-82ee72b054a4
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 6f5459d47972..603c5e3a1e4a 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2015-07-16  Kaz Kojima  <kkojima@gcc.gnu.org>
+
+	PR target/65249
+	* config/sh/sh.md (movdi): Split simple reg move to two movsi
+	when the destination is R0.
+
 2015-07-16  Uros Bizjak  <ubizjak@gmail.com>
 
 	PR target/66866
diff --git a/gcc/config/sh/sh.md b/gcc/config/sh/sh.md
index f0cb3cfe8c4e..61f663778d0a 100644
--- a/gcc/config/sh/sh.md
+++ b/gcc/config/sh/sh.md
@@ -7892,6 +7892,24 @@ label:
   ""
 {
   prepare_move_operands (operands, DImode);
+  if (TARGET_SH1)
+    {
+      /* When the dest operand is (R0, R1) register pair, split it to
+	 two movsi of which dest is R1 and R0 so as to lower R0-register
+	 pressure on the first movsi.  Apply only for simple source not
+	 to make complex rtl here.  */
+      if (REG_P (operands[0])
+	  && REGNO (operands[0]) == R0_REG
+	  && REG_P (operands[1])
+	  && REGNO (operands[1]) >= FIRST_PSEUDO_REGISTER)
+	{
+	  emit_insn (gen_movsi (gen_rtx_REG (SImode, R1_REG),
+			        gen_rtx_SUBREG (SImode, operands[1], 4)));
+	  emit_insn (gen_movsi (gen_rtx_REG (SImode, R0_REG),
+			        gen_rtx_SUBREG (SImode, operands[1], 0)));
+	  DONE;
+	}
+    }
 })
 
 (define_insn "movdf_media"