[tblgen] GCC/MS builtin to target intrisics map.

Patch by Ettore Speziale

Allow TableGen to generate static functions to perform GCC/MS builtin name to
target specific intrinsic ID mapping.

https://reviews.llvm.org/D31150

llvm-svn: 300735

2 files changed, 17 insertions, 7 deletions

diff --git a/llvm/include/llvm/TableGen/StringToOffsetTable.h b/llvm/include/llvm/TableGen/StringToOffsetTable.h
index aaf2a356ffa..4b11e889ea6 100644
--- a/llvm/include/llvm/TableGen/StringToOffsetTable.h
+++ b/llvm/include/llvm/TableGen/StringToOffsetTable.h
@@ -27,6 +27,8 @@ class StringToOffsetTable {
   std::string AggregateString;
 
 public:
+  bool Empty() const { return StringOffset.empty(); }
+
   unsigned GetOrAddStringOffset(StringRef Str, bool appendZero = true) {
     auto IterBool =
         StringOffset.insert(std::make_pair(Str, AggregateString.size()));
diff --git a/llvm/utils/TableGen/IntrinsicEmitter.cpp b/llvm/utils/TableGen/IntrinsicEmitter.cpp
index e9dd2fa0aca..e979b94e46d 100644
--- a/llvm/utils/TableGen/IntrinsicEmitter.cpp
+++ b/llvm/utils/TableGen/IntrinsicEmitter.cpp
@@ -84,14 +84,11 @@ void IntrinsicEmitter::run(raw_ostream &OS) {
   // Emit the intrinsic parameter attributes.
   EmitAttributes(Ints, OS);
 
-  // Individual targets don't need GCC builtin name mappings.
-  if (!TargetOnly) {
-    // Emit code to translate GCC builtins into LLVM intrinsics.
-    EmitIntrinsicToBuiltinMap(Ints, true, OS);
+  // Emit code to translate GCC builtins into LLVM intrinsics.
+  EmitIntrinsicToBuiltinMap(Ints, true, OS);
 
-    // Emit code to translate MS builtins into LLVM intrinsics.
-    EmitIntrinsicToBuiltinMap(Ints, false, OS);
-  }
+  // Emit code to translate MS builtins into LLVM intrinsics.
+  EmitIntrinsicToBuiltinMap(Ints, false, OS);
 
   EmitSuffix(OS);
 }
@@ -756,6 +753,17 @@ void IntrinsicEmitter::EmitIntrinsicToBuiltinMap(
        << "Builtin(const char "
        << "*TargetPrefixStr, StringRef BuiltinNameStr) {\n";
   }
+
+  if (Table.Empty()) {
+    OS << "  return ";
+    if (!TargetPrefix.empty())
+      OS << "(" << TargetPrefix << "Intrinsic::ID)";
+    OS << "Intrinsic::not_intrinsic;\n";
+    OS << "}\n";
+    OS << "#endif\n\n";
+    return;
+  }
+
   OS << "  static const char BuiltinNames[] = {\n";
   Table.EmitCharArray(OS);
   OS << "  };\n\n";