[Power9] Add support for -mcpu=pwr9 in the back end

This patch corresponds to review:
http://reviews.llvm.org/D19683

Simply adds the bits for being able to specify -mcpu=pwr9 to the back end.

llvm-svn: 268950
diff --git a/llvm/lib/Target/PowerPC/PPC.td b/llvm/lib/Target/PowerPC/PPC.td
index f0c2b01..c66e855 100644
--- a/llvm/lib/Target/PowerPC/PPC.td
+++ b/llvm/lib/Target/PowerPC/PPC.td
@@ -47,6 +47,7 @@
 def DirectivePwr6x: SubtargetFeature<"", "DarwinDirective", "PPC::DIR_PWR6X", "">;
 def DirectivePwr7: SubtargetFeature<"", "DarwinDirective", "PPC::DIR_PWR7", "">;
 def DirectivePwr8: SubtargetFeature<"", "DarwinDirective", "PPC::DIR_PWR8", "">;
+def DirectivePwr9: SubtargetFeature<"", "DarwinDirective", "PPC::DIR_PWR9", "">;
 
 def Feature64Bit     : SubtargetFeature<"64bit","Has64BitSupport", "true",
                                         "Enable 64-bit instructions">;
@@ -200,6 +201,8 @@
       !listconcat(Power7FeatureList, Power8SpecificFeatures);
   list<SubtargetFeature> Power9SpecificFeatures =
       [FeatureP9Altivec, FeatureP9Vector, FeatureISA3_0];
+  list<SubtargetFeature> Power9FeatureList =
+      !listconcat(Power8FeatureList, Power9SpecificFeatures);
 }
 
 // Note: Future features to add when support is extended to more
@@ -398,6 +401,8 @@
                    FeatureMFTB, DeprecatedDST]>;
 def : ProcessorModel<"pwr7", P7Model, ProcessorFeatures.Power7FeatureList>;
 def : ProcessorModel<"pwr8", P8Model, ProcessorFeatures.Power8FeatureList>;
+// FIXME: Same as P8 until the POWER9 scheduling info is available
+def : ProcessorModel<"pwr9", P8Model, ProcessorFeatures.Power9FeatureList>;
 def : Processor<"ppc", G3Itineraries, [Directive32, FeatureMFTB]>;
 def : ProcessorModel<"ppc64", G5Model,
                   [Directive64, FeatureAltivec,
diff --git a/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp b/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
index ac9d19c..ecf184e 100644
--- a/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
+++ b/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
@@ -1306,8 +1306,10 @@
     "power6",
     "power6x",
     "power7",
+    // FIXME: why is power8 missing here?
     "ppc64",
-    "ppc64le"
+    "ppc64le",
+    "power9"
   };
 
   // Get the numerically largest directive.
diff --git a/llvm/lib/Target/PowerPC/PPCHazardRecognizers.cpp b/llvm/lib/Target/PowerPC/PPCHazardRecognizers.cpp
index 7234e30..caab67d 100644
--- a/llvm/lib/Target/PowerPC/PPCHazardRecognizers.cpp
+++ b/llvm/lib/Target/PowerPC/PPCHazardRecognizers.cpp
@@ -162,8 +162,9 @@
     unsigned Directive =
         DAG->MF.getSubtarget<PPCSubtarget>().getDarwinDirective();
     // If we're using a special group-terminating nop, then we need only one.
+    // FIXME: the same for P9 as previous gen until POWER9 scheduling is ready
     if (Directive == PPC::DIR_PWR6 || Directive == PPC::DIR_PWR7 ||
-        Directive == PPC::DIR_PWR8 )
+        Directive == PPC::DIR_PWR8 || Directive == PPC::DIR_PWR9)
       return 1;
 
     return 5 - CurSlots;
@@ -223,8 +224,10 @@
       DAG->MF.getSubtarget<PPCSubtarget>().getDarwinDirective();
   // If the group has now filled all of its slots, or if we're using a special
   // group-terminating nop, the group is complete.
+  // FIXME: the same for P9 as previous gen until POWER9 scheduling is ready
   if (Directive == PPC::DIR_PWR6 || Directive == PPC::DIR_PWR7 ||
-      Directive == PPC::DIR_PWR8 || CurSlots == 6)  {
+      Directive == PPC::DIR_PWR8 || Directive == PPC::DIR_PWR8 ||
+      CurSlots == 6) {
     CurGroup.clear();
     CurSlots = CurBranches = 0;
   } else {
diff --git a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
index 813bf27..bb6a0c5 100644
--- a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -916,6 +916,7 @@
   case PPC::DIR_PWR6X:
   case PPC::DIR_PWR7:
   case PPC::DIR_PWR8:
+  case PPC::DIR_PWR9:
     setPrefFunctionAlignment(4);
     setPrefLoopAlignment(4);
     break;
@@ -11187,7 +11188,8 @@
   case PPC::DIR_PWR6:
   case PPC::DIR_PWR6X:
   case PPC::DIR_PWR7:
-  case PPC::DIR_PWR8: {
+  case PPC::DIR_PWR8:
+  case PPC::DIR_PWR9: {
     if (!ML)
       break;
 
diff --git a/llvm/lib/Target/PowerPC/PPCInstrInfo.cpp b/llvm/lib/Target/PowerPC/PPCInstrInfo.cpp
index 204dc28..313ab88 100644
--- a/llvm/lib/Target/PowerPC/PPCInstrInfo.cpp
+++ b/llvm/lib/Target/PowerPC/PPCInstrInfo.cpp
@@ -93,6 +93,7 @@
   unsigned Directive =
       DAG->MF.getSubtarget<PPCSubtarget>().getDarwinDirective();
 
+  // FIXME: Leaving this as-is until we have POWER9 scheduling info
   if (Directive == PPC::DIR_PWR7 || Directive == PPC::DIR_PWR8)
     return new PPCDispatchGroupSBHazardRecognizer(II, DAG);
 
@@ -181,6 +182,7 @@
     case PPC::DIR_PWR6X:
     case PPC::DIR_PWR7:
     case PPC::DIR_PWR8:
+    // FIXME: Is this needed for POWER9?
       Latency += 2;
       break;
     }
@@ -428,6 +430,8 @@
   case PPC::DIR_PWR6: Opcode = PPC::NOP_GT_PWR6; break;
   case PPC::DIR_PWR7: Opcode = PPC::NOP_GT_PWR7; break;
   case PPC::DIR_PWR8: Opcode = PPC::NOP_GT_PWR7; break; /* FIXME: Update when P8 InstrScheduling model is ready */
+  // FIXME: Update when POWER9 scheduling model is ready.
+  case PPC::DIR_PWR9: Opcode = PPC::NOP_GT_PWR7; break;
   }
 
   DebugLoc DL;
diff --git a/llvm/lib/Target/PowerPC/PPCSubtarget.cpp b/llvm/lib/Target/PowerPC/PPCSubtarget.cpp
index 57de0b6..b87e5a8 100644
--- a/llvm/lib/Target/PowerPC/PPCSubtarget.cpp
+++ b/llvm/lib/Target/PowerPC/PPCSubtarget.cpp
@@ -170,6 +170,8 @@
   case PPC::DIR_E5500:
   case PPC::DIR_PWR7:
   case PPC::DIR_PWR8:
+  // FIXME: Same as P8 until POWER9 scheduling info is available
+  case PPC::DIR_PWR9:
     return true;
   }
 }
diff --git a/llvm/lib/Target/PowerPC/PPCSubtarget.h b/llvm/lib/Target/PowerPC/PPCSubtarget.h
index da7df79..55500d3 100644
--- a/llvm/lib/Target/PowerPC/PPCSubtarget.h
+++ b/llvm/lib/Target/PowerPC/PPCSubtarget.h
@@ -56,6 +56,7 @@
     DIR_PWR6X,
     DIR_PWR7,
     DIR_PWR8,
+    DIR_PWR9,
     DIR_64
   };
 }
diff --git a/llvm/lib/Target/PowerPC/PPCTargetTransformInfo.cpp b/llvm/lib/Target/PowerPC/PPCTargetTransformInfo.cpp
index 85a684a..9331e41 100644
--- a/llvm/lib/Target/PowerPC/PPCTargetTransformInfo.cpp
+++ b/llvm/lib/Target/PowerPC/PPCTargetTransformInfo.cpp
@@ -267,8 +267,9 @@
 
   // For P7 and P8, floating-point instructions have a 6-cycle latency and
   // there are two execution units, so unroll by 12x for latency hiding.
-  if (Directive == PPC::DIR_PWR7 ||
-      Directive == PPC::DIR_PWR8)
+  // FIXME: the same for P9 as previous gen until POWER9 scheduling is ready
+  if (Directive == PPC::DIR_PWR7 || Directive == PPC::DIR_PWR8 ||
+      Directive == PPC::DIR_PWR9)
     return 12;
 
   // For most things, modern systems have two execution units (and