[Parse] Add platform conditional targetEnvironment(simulator)

Author: graydon

include/swift/Basic/LangOptions.h

@@ -46,6 +46,8 @@ namespace swift {
     Runtime,
     /// Conditional import of module
     CanImport,
+    /// Target Environment (currently just 'simulator' or absent)
+    TargetEnvironment,
   };
 
   /// Describes which Swift 3 Objective-C inference warnings should be
@@ -351,7 +353,7 @@ namespace swift {
     }
 
   private:
-    llvm::SmallVector<std::pair<PlatformConditionKind, std::string>, 4>
+    llvm::SmallVector<std::pair<PlatformConditionKind, std::string>, 5>
         PlatformConditionValues;
     llvm::SmallVector<std::string, 2> CustomConditionalCompilationFlags;
   };

lib/Basic/LangOptions.cpp

@@ -16,6 +16,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "swift/Basic/LangOptions.h"
+#include "swift/Basic/Platform.h"
 #include "swift/Basic/Range.h"
 #include "swift/Config.h"
 #include "llvm/ADT/Hashing.h"
@@ -60,6 +61,10 @@ static const StringRef SupportedConditionalCompilationRuntimes[] = {
   "_Native",
 };
 
+static const StringRef SupportedConditionalCompilationTargetEnvironments[] = {
+  "simulator",
+};
+
 template <size_t N>
 bool contains(const StringRef (&Array)[N], const StringRef &V,
               std::vector<StringRef> &suggestions) {
@@ -99,6 +104,9 @@ checkPlatformConditionSupported(PlatformConditionKind Kind, StringRef Value,
   case PlatformConditionKind::Runtime:
     return contains(SupportedConditionalCompilationRuntimes, Value,
                     suggestions);
+  case PlatformConditionKind::TargetEnvironment:
+    return contains(SupportedConditionalCompilationTargetEnvironments, Value,
+                    suggestions);
   case PlatformConditionKind::CanImport:
     // All importable names are valid.
     // FIXME: Perform some kind of validation of the string?
@@ -254,6 +262,13 @@ std::pair<bool, bool> LangOptions::setTarget(llvm::Triple triple) {
   else
     addPlatformConditionValue(PlatformConditionKind::Runtime, "_Native");
 
+  // Set the "targetEnvironment" platform condition if targeting a simulator
+  // environmet. Otherwise _no_ value is present for targetEnvironment; it's
+  // an optional disambiguating refinement of the triple.
+  if (swift::tripleIsAnySimulator(Target))
+    addPlatformConditionValue(PlatformConditionKind::TargetEnvironment,
+                              "simulator");
+
   // If you add anything to this list, change the default size of
   // PlatformConditionValues to not require an extra allocation
   // in the common case.

lib/Parse/ParseIfConfig.cpp

@@ -37,6 +37,7 @@ Optional<PlatformConditionKind> getPlatformConditionKind(StringRef Name) {
     .Case("_endian", PlatformConditionKind::Endianness)
     .Case("_runtime", PlatformConditionKind::Runtime)
     .Case("canImport", PlatformConditionKind::CanImport)
+    .Case("targetEnvironment", PlatformConditionKind::TargetEnvironment)
     .Default(None);
 }
 
@@ -325,6 +326,8 @@ class ValidateIfConfigCondition :
         DiagName = "endianness"; break;
       case PlatformConditionKind::CanImport:
         DiagName = "import conditional"; break;
+      case PlatformConditionKind::TargetEnvironment:
+        DiagName = "target environment"; break;
       case PlatformConditionKind::Runtime:
         llvm_unreachable("handled above");
       }

test/Parse/ConditionalCompilation/identifierName.swift

@@ -6,9 +6,11 @@ func f2(
   FOO: Int,
   swift: Int, _compiler_version: Int,
   os: Int, arch: Int, _endian: Int, _runtime: Int,
+  targetEnvironment: Int,
   arm: Int, i386: Int, macOS: Int, OSX: Int, Linux: Int,
   big: Int, little: Int,
-  _ObjC: Int, _Native: Int
+  _ObjC: Int, _Native: Int,
+  simulator: Int
 ) {
 
 #if FOO
@@ -23,6 +25,8 @@ func f2(
   _ = _runtime + _ObjC + _Native
 #elseif swift(>=1.0) && _compiler_version("3.*.0")
   _ = swift + _compiler_version
+#elseif targetEnvironment(simulator)
+  _ = targetEnvironment + simulator
 #endif
 
 }
@@ -31,9 +35,11 @@ func f2() {
   let
     FOO = 1, swift = 1, _compiler_version = 1,
     os = 1, arch = 1, _endian = 1, _runtime = 1,
+    targetEnvironment = 1,
     arm = 1, i386 = 1, macOS = 1, OSX = 1, Linux = 1,
     big = 1, little = 1,
-    _ObjC = 1, _Native = 1
+    _ObjC = 1, _Native = 1,
+    simulator = 1
 
 #if FOO
   _ = FOO
@@ -47,6 +53,8 @@ func f2() {
   _ = _runtime + _ObjC + _Native
 #elseif swift(>=1.0) && _compiler_version("3.*.0")
   _ = swift + _compiler_version
+#elseif targetEnvironment(simulator)
+  _ = targetEnvironment + simulator
 #endif
 
 }
@@ -55,16 +63,19 @@ struct S {
   let
     FOO = 1, swift = 1, _compiler_version = 1,
     os = 1, arch = 1, _endian = 1, _runtime = 1,
+    targetEnvironment = 1,
     arm = 1, i386 = 1, macOS = 1, OSX = 1, Linux = 1,
     big = 1, little = 1,
-    _ObjC = 1, _Native = 1
+    _ObjC = 1, _Native = 1,
+    simulator = 1
 
 #if FOO
 #elseif os(macOS) && os(OSX) && os(Linux)
 #elseif arch(i386) && arch(arm)
 #elseif _endian(big) && _endian(little)
 #elseif _runtime(_ObjC) && _runtime(_Native)
 #elseif swift(>=1.0) && _compiler_version("3.*.0")
+#elseif targetEnvironment(simulator)
 #endif
 
 }

test/Parse/ConditionalCompilation/simulatorTargetEnv.swift

@@ -0,0 +1,13 @@
+// RUN: %swift -typecheck %s -verify -target x86_64-apple-ios7.0 -parse-stdlib
+// RUN: %swift-ide-test -test-input-complete -source-filename=%s -target x86_64-apple-ios7.0
+
+#if !targetEnvironment(simulator)
+// This block should not parse.
+let i: Int = "Hello"
+#endif
+
+#if targetEnvironment(simulator)
+class C {}
+var x = C()
+#endif
+var y = x