From 0637d38ec2b79712468c535730be8a055fcc2357 Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Fri, 23 Dec 2005 05:48:07 +0000
Subject: [PATCH] Simplify store(bitconv(x)) to store(x).  This allows us to
 compile this:

void bar(double Y, double *X) {
  *X = Y;
}

to this:

bar:
        save -96, %o6, %o6
        st %i1, [%i2+4]
        st %i0, [%i2]
        restore %g0, %g0, %g0
        retl
        nop

instead of this:

bar:
        save -104, %o6, %o6
        st %i1, [%i6+-4]
        st %i0, [%i6+-8]
        ldd [%i6+-8], %f0
        std  %f0, [%i2]
        restore %g0, %g0, %g0
        retl
        nop

on sparcv8.

llvm-svn: 24983
---
 lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index f08fd10413c..52e8391f372 100644
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -2081,6 +2081,11 @@ SDOperand DAGCombiner::visitSTORE(SDNode *N) {
     return SDOperand(N, 0);
   }
   
+  // If this is a store of a bit convert, store the input value.
+  if (Value.getOpcode() == ISD::BIT_CONVERT)
+    return DAG.getNode(ISD::STORE, MVT::Other, Chain, Value.getOperand(0),
+                       Ptr, SrcValue);
+  
   return SDOperand();
 }