Initial set of .td file changes necessary to get scalar fp in xmm registers
working.  The instruction selector changes will hopefully be coming later
this week once they are debugged.  This is necessary to support the darwin
x86 FP model, and is recommended by intel as the replacement for x87.  As
a bonus, the register allocator knows how to deal with these registers
across basic blocks, unliky the FP stackifier.  This leads to significantly
better codegen in several cases.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22300 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86RegisterInfo.td b/lib/Target/X86/X86RegisterInfo.td
index f0ab68d..da8e612 100644
--- a/lib/Target/X86/X86RegisterInfo.td
+++ b/lib/Target/X86/X86RegisterInfo.td
@@ -47,6 +47,12 @@
   def FP4 : Register<"FP4">; def FP5 : Register<"FP5">;
   def FP6 : Register<"FP6">; 
 
+  // XMM Registers, used by the various SSE instruction set extensions
+  def XMM0: Register<"XMM0">; def XMM1: Register<"XMM1">;
+  def XMM2: Register<"XMM2">; def XMM3: Register<"XMM3">;
+  def XMM4: Register<"XMM4">; def XMM5: Register<"XMM5">;
+  def XMM6: Register<"XMM6">; def XMM7: Register<"XMM7">;
+
   // Floating point stack registers
   def ST0 : Register<"ST(0)">; def ST1 : Register<"ST(1)">;
   def ST2 : Register<"ST(2)">; def ST3 : Register<"ST(3)">;
@@ -90,6 +96,12 @@
   }];
 }
 
+// FIXME: These registers can contain both integer and fp values.  We should
+// figure out the right way to deal with that.  For now, since they'll be used
+// for scalar FP, they are being declared f64
+def RXMM : RegisterClass<f64, 128, [XMM0, XMM1, XMM2, XMM3, 
+                                    XMM4, XMM5, XMM6, XMM7]>;
+
 // FIXME: This sets up the floating point register files as though they are f64
 // values, though they really are f80 values.  This will cause us to spill
 // values as 64-bit quantities instead of 80-bit quantities, which is much much