fix CodeGen/X86/2007-02-25-FastCCStack.ll, a regression from my patch last
night:  fastcc returns should only go in XMM0 if we have SSE2 or above.

llvm-svn: 34613
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index ffd24ee..50acc30 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -456,7 +456,7 @@
   case MVT::f64:
     if (Subtarget->is64Bit())
       Reg = X86::XMM0;         // FP values in X86-64 go in XMM0.
-    else if (CC == CallingConv::Fast)
+    else if (CC == CallingConv::Fast && Subtarget->hasSSE2())
       Reg = X86::XMM0;         // FP values in X86-32 with fastcc go in XMM0.
     else
       Reg = X86::ST0;          // FP values in X86-32 go in ST0.