Store the warning option corresponding to a diagnostics as an index into the option table instead of storing the name.

Another 8 bytes + relocation removed from every diagnostic on x86_64.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@150615 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 39 insertions, 26 deletions

diff --git a/lib/Basic/DiagnosticIDs.cpp b/lib/Basic/DiagnosticIDs.cpp
index 754d7c0322..2f28c5dbf7 100644
--- a/lib/Basic/DiagnosticIDs.cpp
+++ b/lib/Basic/DiagnosticIDs.cpp
@@ -52,16 +52,13 @@ struct StaticDiagInfoRec {
   unsigned WarnShowInSystemHeader : 1;
   unsigned Category : 5;
 
-  uint8_t  OptionGroupLen;
+  uint16_t OptionGroupIndex;
 
   uint16_t DescriptionLen;
-
-  const char *OptionGroupStr;
-
   const char *DescriptionStr;
 
-  StringRef getOptionGroup() const {
-    return StringRef(OptionGroupStr, OptionGroupLen);
+  unsigned getOptionGroupIndex() const {
+    return OptionGroupIndex;
   }
 
   StringRef getDescription() const {
@@ -89,10 +86,8 @@ static const StaticDiagInfoRec StaticDiagInfo[] = {
              SFINAE,ACCESS,NOWERROR,SHOWINSYSHEADER,              \
              CATEGORY)                                            \
   { diag::ENUM, DEFAULT_MAPPING, CLASS, SFINAE, ACCESS,           \
-    NOWERROR, SHOWINSYSHEADER, CATEGORY,                          \
-    STR_SIZE(GROUP, uint8_t),           \
-    STR_SIZE(DESC, uint16_t),                                     \
-    GROUP, DESC },
+    NOWERROR, SHOWINSYSHEADER, CATEGORY, GROUP,                   \
+    STR_SIZE(DESC, uint16_t), DESC },
 #include "clang/Basic/DiagnosticCommonKinds.inc"
 #include "clang/Basic/DiagnosticDriverKinds.inc"
 #include "clang/Basic/DiagnosticFrontendKinds.inc"
@@ -103,7 +98,7 @@ static const StaticDiagInfoRec StaticDiagInfo[] = {
 #include "clang/Basic/DiagnosticSemaKinds.inc"
 #include "clang/Basic/DiagnosticAnalysisKinds.inc"
 #undef DIAG
-  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
+  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
 };
 
 static const unsigned StaticDiagInfoSize =
@@ -130,7 +125,7 @@ static const StaticDiagInfoRec *GetDiagInfo(unsigned DiagID) {
 
   // Search the diagnostic table with a binary search.
   StaticDiagInfoRec Find = { static_cast<unsigned short>(DiagID),
-                             0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
+                             0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
 
   const StaticDiagInfoRec *Found =
     std::lower_bound(StaticDiagInfo, StaticDiagInfo + StaticDiagInfoSize, Find);
@@ -164,15 +159,6 @@ static DiagnosticMappingInfo GetDefaultDiagMappingInfo(unsigned DiagID) {
   return Info;
 }
 
-/// getWarningOptionForDiag - Return the lowest-level warning option that
-/// enables the specified diagnostic.  If there is no -Wfoo flag that controls
-/// the diagnostic, this returns null.
-StringRef DiagnosticIDs::getWarningOptionForDiag(unsigned DiagID) {
-  if (const StaticDiagInfoRec *Info = GetDiagInfo(DiagID))
-    return Info->getOptionGroup();
-  return StringRef();
-}
-
 /// getCategoryNumberForDiag - Return the category number that a specified
 /// DiagID belongs to, or 0 if no category.
 unsigned DiagnosticIDs::getCategoryNumberForDiag(unsigned DiagID) {
@@ -531,6 +517,15 @@ static bool WarningOptionCompare(const WarningOption &LHS,
   return LHS.getName() < RHS.getName();
 }
 
+/// getWarningOptionForDiag - Return the lowest-level warning option that
+/// enables the specified diagnostic.  If there is no -Wfoo flag that controls
+/// the diagnostic, this returns null.
+StringRef DiagnosticIDs::getWarningOptionForDiag(unsigned DiagID) {
+  if (const StaticDiagInfoRec *Info = GetDiagInfo(DiagID))
+    return OptionTable[Info->getOptionGroupIndex()].getName();
+  return StringRef();
+}
+
 void DiagnosticIDs::getDiagnosticsInGroup(
   const WarningOption *Group,
   llvm::SmallVectorImpl<diag::kind> &Diags) const
diff --git a/utils/TableGen/ClangDiagnosticsEmitter.cpp b/utils/TableGen/ClangDiagnosticsEmitter.cpp
index 4b041fee87..529e7ecd6a 100644
--- a/utils/TableGen/ClangDiagnosticsEmitter.cpp
+++ b/utils/TableGen/ClangDiagnosticsEmitter.cpp
@@ -21,6 +21,7 @@
 #include <map>
 #include <algorithm>
 #include <functional>
+#include <set>
 using namespace llvm;
 
 //===----------------------------------------------------------------------===//
@@ -138,7 +139,21 @@ void ClangDiagsDefsEmitter::run(raw_ostream &OS) {
 
   const std::vector<Record*> &Diags =
     Records.getAllDerivedDefinitions("Diagnostic");
-  
+
+  // Make a sorted set of all warning opts so we can get the index.
+  std::set<std::string> WarningOpts;
+  for (unsigned i = 0, e = Diags.size(); i != e; ++i) {
+    const Record *R = Diags[i];
+    DefInit *DI = dynamic_cast<DefInit*>(R->getValueInit("Group"));
+    if (DI)
+      WarningOpts.insert(DI->getDef()->getValueAsString("GroupName"));
+  }
+
+  std::vector<Record*> DiagGroups
+    = Records.getAllDerivedDefinitions("DiagGroup");
+  for (unsigned i = 0, e = DiagGroups.size(); i != e; ++i)
+    WarningOpts.insert(DiagGroups[i]->getValueAsString("GroupName"));
+
   DiagCategoryIDMap CategoryIDs(Records);
   DiagGroupParentMap DGParentMap(Records);
 
@@ -156,12 +171,15 @@ void ClangDiagsDefsEmitter::run(raw_ostream &OS) {
     OS << ", \"";
     OS.write_escaped(R.getValueAsString("Text")) << '"';
     
-    // Warning associated with the diagnostic.
+    // Warning associated with the diagnostic. This is stored as an index into
+    // the alphabetically sorted warning table.
     if (DefInit *DI = dynamic_cast<DefInit*>(R.getValueInit("Group"))) {
-      OS << ", \"";
-      OS.write_escaped(DI->getDef()->getValueAsString("GroupName")) << '"';
+      std::set<std::string>::iterator I =
+        WarningOpts.find(DI->getDef()->getValueAsString("GroupName"));
+      assert(I != WarningOpts.end());
+      OS << ", " << std::distance(WarningOpts.begin(), I);
     } else {
-      OS << ", \"\"";
+      OS << ", 0";
     }
 
     // SFINAE bit