[AArch64] Add an SVE target feature to the backend and TargetParser.

The feature will be used properly once assembler/disassembler support
begins to land.

llvm-svn: 307917
diff --git a/llvm/lib/Support/TargetParser.cpp b/llvm/lib/Support/TargetParser.cpp
index 13bb6f2..e8ef1d2 100644
--- a/llvm/lib/Support/TargetParser.cpp
+++ b/llvm/lib/Support/TargetParser.cpp
@@ -452,6 +452,8 @@
     Features.push_back("+ras");
   if (Extensions & AArch64::AEK_LSE)
     Features.push_back("+lse");
+  if (Extensions & AArch64::AEK_SVE)
+    Features.push_back("+sve");
 
   return true;
 }
diff --git a/llvm/lib/Target/AArch64/AArch64.td b/llvm/lib/Target/AArch64/AArch64.td
index 53eef79..cfda016 100644
--- a/llvm/lib/Target/AArch64/AArch64.td
+++ b/llvm/lib/Target/AArch64/AArch64.td
@@ -50,6 +50,9 @@
 def FeatureSPE : SubtargetFeature<"spe", "HasSPE", "true",
   "Enable Statistical Profiling extension">;
 
+def FeatureSVE : SubtargetFeature<"sve", "HasSVE", "true",
+  "Enable Scalable Vector Extension (SVE) instructions">;
+
 /// Cyclone has register move instructions which are "free".
 def FeatureZCRegMove : SubtargetFeature<"zcm", "HasZeroCycleRegMove", "true",
                                         "Has zero-cycle register moves">;
diff --git a/llvm/lib/Target/AArch64/AArch64InstrInfo.td b/llvm/lib/Target/AArch64/AArch64InstrInfo.td
index 0be1467..0dcf07f 100644
--- a/llvm/lib/Target/AArch64/AArch64InstrInfo.td
+++ b/llvm/lib/Target/AArch64/AArch64InstrInfo.td
@@ -37,6 +37,8 @@
                                  AssemblerPredicate<"FeatureFullFP16", "fullfp16">;
 def HasSPE           : Predicate<"Subtarget->hasSPE()">,
                                  AssemblerPredicate<"FeatureSPE", "spe">;
+def HasSVE           : Predicate<"Subtarget->hasSVE()">,
+                                 AssemblerPredicate<"FeatureSVE", "sve">;
 
 def IsLE             : Predicate<"Subtarget->isLittleEndian()">;
 def IsBE             : Predicate<"!Subtarget->isLittleEndian()">;
diff --git a/llvm/lib/Target/AArch64/AArch64Subtarget.h b/llvm/lib/Target/AArch64/AArch64Subtarget.h
index db53946..917036d 100644
--- a/llvm/lib/Target/AArch64/AArch64Subtarget.h
+++ b/llvm/lib/Target/AArch64/AArch64Subtarget.h
@@ -70,6 +70,7 @@
   bool HasFullFP16 = false;
   bool HasSPE = false;
   bool HasLSLFast = false;
+  bool HasSVE = false;
 
   // HasZeroCycleRegMove - Has zero-cycle register mov instructions.
   bool HasZeroCycleRegMove = false;
@@ -251,6 +252,7 @@
   bool hasFullFP16() const { return HasFullFP16; }
   bool hasSPE() const { return HasSPE; }
   bool hasLSLFast() const { return HasLSLFast; }
+  bool hasSVE() const { return HasSVE; }
 
   bool isLittleEndian() const { return IsLittle; }