[asm parser] Add support for predicating MnemonicAlias based on the assembler

variant/dialect.  Addresses a FIXME in the emitMnemonicAliases function.
Use and test case to come shortly.
rdar://13688439 and part of PR13340.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179804 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 45 insertions, 20 deletions

diff --git a/utils/TableGen/AsmMatcherEmitter.cpp b/utils/TableGen/AsmMatcherEmitter.cpp
index 6faf819..65d7859 100644
--- a/utils/TableGen/AsmMatcherEmitter.cpp
+++ b/utils/TableGen/AsmMatcherEmitter.cpp
@@ -2296,29 +2296,25 @@ static std::string GetAliasRequiredFeatures(Record *R,
   return Result;
 }
 
-/// emitMnemonicAliases - If the target has any MnemonicAlias<> definitions,
-/// emit a function for them and return true, otherwise return false.
-static bool emitMnemonicAliases(raw_ostream &OS, const AsmMatcherInfo &Info) {
-  // Ignore aliases when match-prefix is set.
-  if (!MatchPrefix.empty())
-    return false;
-
-  std::vector<Record*> Aliases =
-    Info.getRecords().getAllDerivedDefinitions("MnemonicAlias");
-  if (Aliases.empty()) return false;
-
-  OS << "static void applyMnemonicAliases(StringRef &Mnemonic, "
-        "unsigned Features) {\n";
-
+static void emitMnemonicAliasVariant(raw_ostream &OS,const AsmMatcherInfo &Info,
+                                     std::vector<Record*> &Aliases,
+                                     unsigned Indent = 0,
+                                  StringRef AsmParserVariantName = StringRef()){
   // Keep track of all the aliases from a mnemonic.  Use an std::map so that the
   // iteration order of the map is stable.
   std::map<std::string, std::vector<Record*> > AliasesFromMnemonic;
 
   for (unsigned i = 0, e = Aliases.size(); i != e; ++i) {
     Record *R = Aliases[i];
+    // FIXME: Allow AssemblerVariantName to be a comma separated list.
+    std::string AsmVariantName = R->getValueAsString("AsmVariantName");
+    if (AsmVariantName != AsmParserVariantName)
+      continue;
     AliasesFromMnemonic[R->getValueAsString("FromMnemonic")].push_back(R);
   }
-
+  if (AliasesFromMnemonic.empty())
+    return;
+    
   // Process each alias a "from" mnemonic at a time, building the code executed
   // by the string remapper.
   std::vector<StringMatcher::StringPair> Cases;
@@ -2370,8 +2366,39 @@ static bool emitMnemonicAliases(raw_ostream &OS, const AsmMatcherInfo &Info) {
 
     Cases.push_back(std::make_pair(I->first, MatchCode));
   }
+  StringMatcher("Mnemonic", Cases, OS).Emit(Indent);
+}
+
+/// emitMnemonicAliases - If the target has any MnemonicAlias<> definitions,
+/// emit a function for them and return true, otherwise return false.
+static bool emitMnemonicAliases(raw_ostream &OS, const AsmMatcherInfo &Info,
+                                CodeGenTarget &Target) {
+  // Ignore aliases when match-prefix is set.
+  if (!MatchPrefix.empty())
+    return false;
+
+  std::vector<Record*> Aliases =
+    Info.getRecords().getAllDerivedDefinitions("MnemonicAlias");
+  if (Aliases.empty()) return false;
+
+  OS << "static void applyMnemonicAliases(StringRef &Mnemonic, "
+    "unsigned Features, unsigned VariantID) {\n";
+  OS << "  switch (VariantID) {\n";
+  unsigned VariantCount = Target.getAsmParserVariantCount();
+  for (unsigned VC = 0; VC != VariantCount; ++VC) {
+    Record *AsmVariant = Target.getAsmParserVariant(VC);
+    int AsmParserVariantNo = AsmVariant->getValueAsInt("Variant");
+    std::string AsmParserVariantName = AsmVariant->getValueAsString("Name");
+    OS << "    case " << AsmParserVariantNo << ":\n";
+    emitMnemonicAliasVariant(OS, Info, Aliases, /*Indent=*/2,
+                             AsmParserVariantName);
+    OS << "    break;\n";
+  }
+  OS << "  }\n";
+
+  // Emit aliases that apply to all variants.
+  emitMnemonicAliasVariant(OS, Info, Aliases);
 
-  StringMatcher("Mnemonic", Cases, OS).Emit();
   OS << "}\n\n";
 
   return true;
@@ -2674,7 +2701,7 @@ void AsmMatcherEmitter::run(raw_ostream &OS) {
   OS << "#undef GET_MATCHER_IMPLEMENTATION\n\n";
 
   // Generate the function that remaps for mnemonic aliases.
-  bool HasMnemonicAliases = emitMnemonicAliases(OS, Info);
+  bool HasMnemonicAliases = emitMnemonicAliases(OS, Info, Target);
 
   // Generate the convertToMCInst function to convert operands into an MCInst.
   // Also, generate the convertToMapAndConstraints function for MS-style inline
@@ -2832,9 +2859,7 @@ void AsmMatcherEmitter::run(raw_ostream &OS) {
 
   if (HasMnemonicAliases) {
     OS << "  // Process all MnemonicAliases to remap the mnemonic.\n";
-    OS << "  // FIXME : Add an entry in AsmParserVariant to check this.\n";
-    OS << "  if (!VariantID)\n";
-    OS << "    applyMnemonicAliases(Mnemonic, AvailableFeatures);\n\n";
+    OS << "  applyMnemonicAliases(Mnemonic, AvailableFeatures, VariantID);\n\n";
   }
 
   // Emit code to compute the class list for this operand vector.