Add support for modeling whether or not the processor has support for
conditional moves as a subtarget feature.  This is the easy part of 
PR4841.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80763 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86.td b/lib/Target/X86/X86.td
index e7aa1f2..203dd37 100644
--- a/lib/Target/X86/X86.td
+++ b/lib/Target/X86/X86.td
@@ -19,12 +19,17 @@
 //===----------------------------------------------------------------------===//
 // X86 Subtarget features.
 //===----------------------------------------------------------------------===//
- 
+
+def FeatureCMOV    : SubtargetFeature<"cmov","HasCMov", "true",
+                                      "Enable conditional move instructions">;
+
 def FeatureMMX     : SubtargetFeature<"mmx","X86SSELevel", "MMX",
                                       "Enable MMX instructions">;
 def FeatureSSE1    : SubtargetFeature<"sse", "X86SSELevel", "SSE1",
                                       "Enable SSE instructions",
-                                      [FeatureMMX]>;
+                                      // SSE codegen depends on cmovs, and all
+                                      // SSE1+ processors support them. 
+                                      [FeatureMMX, FeatureCMOV]>;
 def FeatureSSE2    : SubtargetFeature<"sse2", "X86SSELevel", "SSE2",
                                       "Enable SSE2 instructions",
                                       [FeatureSSE1]>;
@@ -76,8 +81,8 @@
 def : Proc<"pentium",         []>;
 def : Proc<"pentium-mmx",     [FeatureMMX]>;
 def : Proc<"i686",            []>;
-def : Proc<"pentiumpro",      []>;
-def : Proc<"pentium2",        [FeatureMMX]>;
+def : Proc<"pentiumpro",      [FeatureCMOV]>;
+def : Proc<"pentium2",        [FeatureMMX, FeatureCMOV]>;
 def : Proc<"pentium3",        [FeatureSSE1]>;
 def : Proc<"pentium-m",       [FeatureSSE2, FeatureSlowBTMem]>;
 def : Proc<"pentium4",        [FeatureSSE2]>;