[TTI][X86] Reordered getCmpSelInstrCost cost tables in descending ISA order. NFCI.

Minor tidyup to make it clearer whats going on before adding additional costs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@351683 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86TargetTransformInfo.cpp b/lib/Target/X86/X86TargetTransformInfo.cpp
index 131483f..4430079 100644
--- a/lib/Target/X86/X86TargetTransformInfo.cpp
+++ b/lib/Target/X86/X86TargetTransformInfo.cpp
@@ -1650,17 +1650,23 @@
   int ISD = TLI->InstructionOpcodeToISD(Opcode);
   assert(ISD && "Invalid opcode");
 
-  static const CostTblEntry SSE2CostTbl[] = {
-    { ISD::SETCC,   MVT::v2i64,   8 },
-    { ISD::SETCC,   MVT::v4i32,   1 },
-    { ISD::SETCC,   MVT::v8i16,   1 },
-    { ISD::SETCC,   MVT::v16i8,   1 },
+  static const CostTblEntry AVX512BWCostTbl[] = {
+    { ISD::SETCC,   MVT::v32i16,  1 },
+    { ISD::SETCC,   MVT::v64i8,   1 },
   };
 
-  static const CostTblEntry SSE42CostTbl[] = {
-    { ISD::SETCC,   MVT::v2f64,   1 },
-    { ISD::SETCC,   MVT::v4f32,   1 },
-    { ISD::SETCC,   MVT::v2i64,   1 },
+  static const CostTblEntry AVX512CostTbl[] = {
+    { ISD::SETCC,   MVT::v8i64,   1 },
+    { ISD::SETCC,   MVT::v16i32,  1 },
+    { ISD::SETCC,   MVT::v8f64,   1 },
+    { ISD::SETCC,   MVT::v16f32,  1 },
+  };
+
+  static const CostTblEntry AVX2CostTbl[] = {
+    { ISD::SETCC,   MVT::v4i64,   1 },
+    { ISD::SETCC,   MVT::v8i32,   1 },
+    { ISD::SETCC,   MVT::v16i16,  1 },
+    { ISD::SETCC,   MVT::v32i8,   1 },
   };
 
   static const CostTblEntry AVX1CostTbl[] = {
@@ -1673,23 +1679,17 @@
     { ISD::SETCC,   MVT::v32i8,   4 },
   };
 
-  static const CostTblEntry AVX2CostTbl[] = {
-    { ISD::SETCC,   MVT::v4i64,   1 },
-    { ISD::SETCC,   MVT::v8i32,   1 },
-    { ISD::SETCC,   MVT::v16i16,  1 },
-    { ISD::SETCC,   MVT::v32i8,   1 },
+  static const CostTblEntry SSE42CostTbl[] = {
+    { ISD::SETCC,   MVT::v2f64,   1 },
+    { ISD::SETCC,   MVT::v4f32,   1 },
+    { ISD::SETCC,   MVT::v2i64,   1 },
   };
 
-  static const CostTblEntry AVX512CostTbl[] = {
-    { ISD::SETCC,   MVT::v8i64,   1 },
-    { ISD::SETCC,   MVT::v16i32,  1 },
-    { ISD::SETCC,   MVT::v8f64,   1 },
-    { ISD::SETCC,   MVT::v16f32,  1 },
-  };
-
-  static const CostTblEntry AVX512BWCostTbl[] = {
-    { ISD::SETCC,   MVT::v32i16,  1 },
-    { ISD::SETCC,   MVT::v64i8,   1 },
+  static const CostTblEntry SSE2CostTbl[] = {
+    { ISD::SETCC,   MVT::v2i64,   8 },
+    { ISD::SETCC,   MVT::v4i32,   1 },
+    { ISD::SETCC,   MVT::v8i16,   1 },
+    { ISD::SETCC,   MVT::v16i8,   1 },
   };
 
   if (ST->hasBWI())