Add an XcodeSDK::GetSDKTypeForTriple function

[aprantl]

Summary

This is something used in swift-lldb, but of general usefulness.

[vsk]

lgtm as well

lldb/include/lldb/Utility/XcodeSDK.h

 //===-- XcodeSDK.h ----------------------------------------------*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef LLDB_UTILITY_SDK_H
 #define LLDB_UTILITY_SDK_H
 
 #include "lldb/lldb-forward.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/VersionTuple.h"
 #include <tuple>
 
+namespace llvm {
+class Triple;
+}
+
 namespace lldb_private {
 
 /// An abstraction for Xcode-style SDKs that works like \ref ArchSpec.
 class XcodeSDK {
   std::string m_name;
 
 public:
   XcodeSDK() = default;
public:
   llvm::VersionTuple GetVersion() const;
   Type GetType() const;
   llvm::StringRef GetString() const;
 
   static bool SDKSupportsModules(Type type, llvm::VersionTuple version);
   static bool SDKSupportsModules(Type desired_type, const FileSpec &sdk_path);
   /// Return the canonical SDK name, such as "macosx" for the macOS SDK.
   static std::string GetCanonicalName(Info info);
+  /// Return the best-matching SDK type for a specific triple.
+  static XcodeSDK::Type GetSDKTypeForTriple(const llvm::Triple &triple);
 };
 
 } // namespace lldb_private
 
 #endif

lldb/source/Utility/XcodeSDK.cpp

 //===-- XcodeSDK.cpp ------------------------------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
-#include "lldb/Utility/FileSpec.h"
 #include "lldb/Utility/XcodeSDK.h"
+#include "lldb/Utility/FileSpec.h"
 
 #include "lldb/lldb-types.h"
+
+#include "llvm/ADT/Triple.h"
+
 #include <string>
 
 using namespace lldb;
 using namespace lldb_private;
 
 XcodeSDK &XcodeSDK::operator=(XcodeSDK other) {
   m_name = other.m_name;
   return *this;
bool XcodeSDK::SDKSupportsModules(XcodeSDK::Type desired_type,
   if (!last_path_component)
     return false;
 
   XcodeSDK sdk(last_path_component.GetStringRef().str());
   if (sdk.GetType() != desired_type)
     return false;
   return SDKSupportsModules(sdk.GetType(), sdk.GetVersion());
 }
+
+XcodeSDK::Type XcodeSDK::GetSDKTypeForTriple(const llvm::Triple &triple) {
+  using namespace llvm;
+  switch (triple.getOS()) {
+  case Triple::MacOSX:
+  case Triple::Darwin:
+    return XcodeSDK::MacOSX;
+  case Triple::IOS:
+    switch (triple.getEnvironment()) {
+    case Triple::MacABI:
+      return XcodeSDK::MacOSX;
+    case Triple::Simulator:
+      return XcodeSDK::iPhoneSimulator;
+    default:
+      return XcodeSDK::iPhoneOS;
+    }
+  case Triple::TvOS:
+    if (triple.getEnvironment() == Triple::Simulator)
+      return XcodeSDK::AppleTVSimulator;
+    return XcodeSDK::AppleTVOS;
+  case Triple::WatchOS:
+    if (triple.getEnvironment() == Triple::Simulator)
+      return XcodeSDK::WatchSimulator;
+    return XcodeSDK::watchOS;
+  case Triple::Linux:
+    return XcodeSDK::Linux;
+  default:
+    return XcodeSDK::unknown;
+  }
+}

lldb/unittests/Utility/XcodeSDKTest.cpp

 //===-- XcodeSDKTest.cpp --------------------------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #include "gtest/gtest.h"
 
 #include "lldb/Utility/FileSpec.h"
 #include "lldb/Utility/XcodeSDK.h"
 
 #include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/Triple.h"
 
 #include <tuple>
 
 using namespace lldb_private;
 
 TEST(XcodeSDKTest, ParseTest) {
   EXPECT_EQ(XcodeSDK::GetAnyMacOS().GetType(), XcodeSDK::MacOSX);
   EXPECT_EQ(XcodeSDK("MacOSX.sdk").GetType(), XcodeSDK::MacOSX);
TEST(XcodeSDKTest, GetCanonicalName) {
   info.type = XcodeSDK::Type::MacOSX;
   info.version = llvm::VersionTuple(10, 9);
   EXPECT_EQ("macosx10.9.internal", XcodeSDK::GetCanonicalName(info));
 
   info.type = XcodeSDK::Type::iPhoneOS;
   info.version = llvm::VersionTuple(7, 0);
   EXPECT_EQ("iphoneos7.0.internal", XcodeSDK::GetCanonicalName(info));
 }
+
+TEST(XcodeSDKTest, GetSDKTypeForTriple) {
+  EXPECT_EQ(
+      XcodeSDK::GetSDKTypeForTriple(llvm::Triple("x86_64-apple-macosx10.14")),
+      XcodeSDK::Type::MacOSX);
+  EXPECT_EQ(XcodeSDK::GetSDKTypeForTriple(llvm::Triple("x86_64-apple-darwin")),
+            XcodeSDK::Type::MacOSX);
+  EXPECT_EQ(XcodeSDK::GetSDKTypeForTriple(
+                llvm::Triple("x86_64-apple-ios13.4-simulator")),
+            XcodeSDK::Type::iPhoneSimulator);
+  EXPECT_EQ(XcodeSDK::GetSDKTypeForTriple(llvm::Triple("arm64-apple-ios13.4")),
+            XcodeSDK::Type::iPhoneOS);
+  EXPECT_EQ(XcodeSDK::GetSDKTypeForTriple(
+                llvm::Triple("x86_64-apple-ios13.4-macabi")),
+            XcodeSDK::Type::MacOSX);
+  EXPECT_EQ(XcodeSDK::GetSDKTypeForTriple(
+                llvm::Triple("x86_64-apple-tvos-simulator")),
+            XcodeSDK::Type::AppleTVSimulator);
+  EXPECT_EQ(XcodeSDK::GetSDKTypeForTriple(llvm::Triple("arm64-apple-tvos")),
+            XcodeSDK::Type::AppleTVOS);
+  EXPECT_EQ(XcodeSDK::GetSDKTypeForTriple(
+                llvm::Triple("x86_64-apple-watchos-simulator")),
+            XcodeSDK::Type::WatchSimulator);
+  EXPECT_EQ(XcodeSDK::GetSDKTypeForTriple(llvm::Triple("arm64-apple-watchos")),
+            XcodeSDK::Type::watchOS);
+  EXPECT_EQ(XcodeSDK::GetSDKTypeForTriple(llvm::Triple("x86_64-unknown-linux")),
+            XcodeSDK::Type::Linux);
+  EXPECT_EQ(XcodeSDK::GetSDKTypeForTriple(llvm::Triple("i386-unknown-netbsd")),
+            XcodeSDK::Type::unknown);
+}