From 51b58b36f8e3d39eec770d9c0795efa787e47223 Mon Sep 17 00:00:00 2001
From: Aaron Ballman <aaron@aaronballman.com>
Date: Thu, 9 Jan 2014 22:57:44 +0000
Subject: [PATCH] __has_attribute now understands target-specific attributes.
 So when you ask whether an ARM target has the "interrupt" attribute, it will
 return true for ARM and MSP430 targets, and false for others.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@198897 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Lex/PPMacroExpansion.cpp        |  4 +--
 test/Preprocessor/has_attribute.c   | 12 ++++++-
 utils/TableGen/ClangAttrEmitter.cpp | 49 +++++++++++++++++++++++++----
 3 files changed, 56 insertions(+), 9 deletions(-)

diff --git a/lib/Lex/PPMacroExpansion.cpp b/lib/Lex/PPMacroExpansion.cpp
index 3f59758123..c6559b460b 100644
--- a/lib/Lex/PPMacroExpansion.cpp
+++ b/lib/Lex/PPMacroExpansion.cpp
@@ -1045,7 +1045,7 @@ static bool HasExtension(const Preprocessor &PP, const IdentifierInfo *II) {
 
 /// HasAttribute -  Return true if we recognize and implement the attribute
 /// specified by the given identifier.
-static bool HasAttribute(const IdentifierInfo *II) {
+static bool HasAttribute(const IdentifierInfo *II, const llvm::Triple &T) {
   StringRef Name = II->getName();
   // Normalize the attribute name, __foo__ becomes foo.
   if (Name.size() >= 4 && Name.startswith("__") && Name.endswith("__"))
@@ -1395,7 +1395,7 @@ void Preprocessor::ExpandBuiltinMacro(Token &Tok) {
       // Check for a builtin is trivial.
       Value = FeatureII->getBuiltinID() != 0;
     } else if (II == Ident__has_attribute)
-      Value = HasAttribute(FeatureII);
+      Value = HasAttribute(FeatureII, getTargetInfo().getTriple());
     else if (II == Ident__has_extension)
       Value = HasExtension(*this, FeatureII);
     else {
diff --git a/test/Preprocessor/has_attribute.c b/test/Preprocessor/has_attribute.c
index 555c2b3f9e..5fe060e68d 100644
--- a/test/Preprocessor/has_attribute.c
+++ b/test/Preprocessor/has_attribute.c
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -E %s -o - | FileCheck %s
+// RUN: %clang_cc1 -triple arm-unknown-linux -E %s -o - | FileCheck %s
 
 // CHECK: always_inline
 #if __has_attribute(always_inline)
@@ -38,3 +38,13 @@ int has_something_we_dont_have();
 #if !__has_attribute(volatile)
 int has_no_volatile_attribute();
 #endif
+
+// CHECK: has_arm_interrupt
+#if __has_attribute(interrupt)
+  int has_arm_interrupt();
+#endif
+
+// CHECK: does_not_have_dllexport
+#if !__has_attribute(dllexport)
+  int does_not_have_dllexport();
+#endif
diff --git a/utils/TableGen/ClangAttrEmitter.cpp b/utils/TableGen/ClangAttrEmitter.cpp
index a3edd787a4..ed451d559f 100644
--- a/utils/TableGen/ClangAttrEmitter.cpp
+++ b/utils/TableGen/ClangAttrEmitter.cpp
@@ -1537,18 +1537,55 @@ void EmitClangAttrPCHWrite(RecordKeeper &Records, raw_ostream &OS) {
 
 // Emits the list of spellings for attributes.
 void EmitClangAttrSpellingList(RecordKeeper &Records, raw_ostream &OS) {
-  emitSourceFileHeader("llvm::StringSwitch code to match all known attributes",
-                       OS);
+  emitSourceFileHeader("llvm::StringSwitch code to match attributes based on "
+                       "the target triple, T", OS);
 
   std::vector<Record*> Attrs = Records.getAllDerivedDefinitions("Attr");
   
-  for (std::vector<Record*>::iterator I = Attrs.begin(), E = Attrs.end(); I != E; ++I) {
+  for (std::vector<Record*>::iterator I = Attrs.begin(), E = Attrs.end();
+       I != E; ++I) {
     Record &Attr = **I;
 
-    std::vector<Record*> Spellings = Attr.getValueAsListOfDefs("Spellings");
+    // It is assumed that there will be an llvm::Triple object named T within
+    // scope that can be used to determine whether the attribute exists in
+    // a given target.
+    std::string Test;
+    if (Attr.isSubClassOf("TargetSpecificAttr")) {
+      const Record *R = Attr.getValueAsDef("Target");
+      std::vector<std::string> Arches = R->getValueAsListOfStrings("Arches");
+
+      Test += "(";
+      for (std::vector<std::string>::const_iterator AI = Arches.begin(),
+           AE = Arches.end(); AI != AE; ++AI) {
+        std::string Part = *AI;
+        Test += "T.getArch() == llvm::Triple::" + Part;
+        if (AI + 1 != AE)
+          Test += " || ";
+      }
+      Test += ")";
+
+      std::vector<std::string> OSes;
+      if (!R->isValueUnset("OSes")) {
+        Test += " && (";
+        std::vector<std::string> OSes = R->getValueAsListOfStrings("OSes");
+        for (std::vector<std::string>::const_iterator AI = OSes.begin(),
+             AE = OSes.end(); AI != AE; ++AI) {
+          std::string Part = *AI;
+
+          Test += "T.getOS() == llvm::Triple::" + Part;
+          if (AI + 1 != AE)
+            Test += " || ";
+        }
+        Test += ")";
+      }
+    } else
+      Test = "true";
 
-    for (std::vector<Record*>::const_iterator I = Spellings.begin(), E = Spellings.end(); I != E; ++I) {
-      OS << ".Case(\"" << (*I)->getValueAsString("Name") << "\", true)\n";
+    std::vector<Record*> Spellings = Attr.getValueAsListOfDefs("Spellings");
+    for (std::vector<Record*>::const_iterator I = Spellings.begin(),
+         E = Spellings.end(); I != E; ++I) {
+      OS << ".Case(\"" << (*I)->getValueAsString("Name") << "\", " << Test;
+      OS << ")\n";
     }
   }
 
-- 
2.40.0