Reimplement BuildResultOperands to be in terms of the result instruction's

operand list instead of the operand list redundantly declared on the alias
or instruction.

With this change, we finally remove the ins/outs list on the alias.  Before:
  def : InstAlias<(outs GR16:$dst), (ins GR8 :$src),
                  "movsx $src, $dst",
                  (MOVSX16rr8W GR16:$dst, GR8:$src)>;
After:
  def : InstAlias<"movsx $src, $dst",
                  (MOVSX16rr8W GR16:$dst, GR8:$src)>;

This also makes the alias mechanism more general and powerful, which will
be exploited in subsequent patches.

llvm-svn: 118329

llvm/include/llvm/Target/Target.td

@@ -570,9 +570,7 @@ class MnemonicAlias<string From, string To> {
 /// InstAlias - This defines an alternate assembly syntax that is allowed to
 /// match an instruction that has a different (more canonical) assembly
 /// representation.
-class InstAlias<dag Outs, dag Ins, string Asm, dag Result> {
-  dag OutOperandList = Outs;   // An dag containing the MI def operand list.
-  dag InOperandList = Ins;     // An dag containing the MI use operand list.
+class InstAlias<string Asm, dag Result> {
   string AsmString = Asm;      // The .s format to match the instruction with.
   dag ResultInst = Result;     // The MCInst to generate.
   

llvm/lib/Target/X86/X86InstrInfo.td

@@ -1371,50 +1371,37 @@ defm : IntegerCondCodeMnemonicAlias<"cmov", "q">;
 //===----------------------------------------------------------------------===//
 
 // movsx aliases
-def : InstAlias<(outs GR16:$dst), (ins GR8 :$src),
-                "movsx $src, $dst",
+def : InstAlias<"movsx $src, $dst",
                 (MOVSX16rr8W GR16:$dst, GR8:$src)>;
-def : InstAlias<(outs GR16:$dst), (ins i8mem:$src),
-                "movsx $src, $dst",
+def : InstAlias<"movsx $src, $dst",
                 (MOVSX16rm8W GR16:$dst, i8mem:$src)>;
 
-def : InstAlias<(outs GR32:$dst), (ins GR8 :$src),
-                "movsx $src, $dst",
+def : InstAlias<"movsx $src, $dst",
                 (MOVSX32rr8 GR32:$dst, GR8:$src)>;
-def : InstAlias<(outs GR32:$dst), (ins GR16:$src),
-                "movsx $src, $dst",
+def : InstAlias<"movsx $src, $dst",
                 (MOVSX32rr16 GR32:$dst, GR16:$src)>;
 
-def : InstAlias<(outs GR64:$dst), (ins GR8 :$src),
-                "movsx $src, $dst",
+def : InstAlias<"movsx $src, $dst",
                 (MOVSX64rr8 GR64:$dst, GR8:$src)>;
-def : InstAlias<(outs GR64:$dst), (ins GR16:$src),
-                "movsx $src, $dst",
+def : InstAlias<"movsx $src, $dst",
                 (MOVSX64rr16 GR64:$dst, GR16:$src)>;
-def : InstAlias<(outs GR64:$dst), (ins GR32:$src),
-                "movsx $src, $dst",
+def : InstAlias<"movsx $src, $dst",
                 (MOVSX64rr32 GR64:$dst, GR32:$src)>;
 
 // movzx aliases
-def : InstAlias<(outs GR16:$dst), (ins GR8 :$src),
-                "movzx $src, $dst",
+def : InstAlias<"movzx $src, $dst",
                 (MOVZX16rr8W GR16:$dst, GR8:$src)>;
-def : InstAlias<(outs GR16:$dst), (ins i8mem:$src),
-                "movzx $src, $dst",
+def : InstAlias<"movzx $src, $dst",
                 (MOVZX16rm8W GR16:$dst, i8mem:$src)>;
 
-def : InstAlias<(outs GR32:$dst), (ins GR8 :$src),
-                "movzx $src, $dst",
+def : InstAlias<"movzx $src, $dst",
                 (MOVZX32rr8 GR32:$dst, GR8:$src)>;
-def : InstAlias<(outs GR32:$dst), (ins GR16:$src),
-                "movzx $src, $dst",
+def : InstAlias<"movzx $src, $dst",
                 (MOVZX32rr16 GR32:$dst, GR16:$src)>;
 
-def : InstAlias<(outs GR64:$dst), (ins GR8 :$src),
-                "movzx $src, $dst",
+def : InstAlias<"movzx $src, $dst",
                 (MOVZX64rr8_Q GR64:$dst, GR8:$src)>;
-def : InstAlias<(outs GR64:$dst), (ins GR16:$src),
-                "movzx $src, $dst",
+def : InstAlias<"movzx $src, $dst",
                 (MOVZX64rr16_Q GR64:$dst, GR16:$src)>;
 // Note: No GR32->GR64 movzx form.
 

llvm/utils/TableGen/AsmMatcherEmitter.cpp

@@ -313,9 +313,11 @@ struct MatchableInfo {
   /// DefRec - This is the definition that it came from.
   PointerUnion<const CodeGenInstruction*, const CodeGenInstAlias*> DefRec;
   
-  // FIXME: REMOVE.
-  const CGIOperandList &TheOperandList;
-
+  const CodeGenInstruction *getResultInst() const {
+    if (DefRec.is<const CodeGenInstruction*>())
+      return DefRec.get<const CodeGenInstruction*>();
+    return DefRec.get<const CodeGenInstAlias*>()->ResultInst;
+  }
   
   /// ResOperands - This is the operand list that should be built for the result
   /// MCInst.
@@ -344,13 +346,11 @@ struct MatchableInfo {
   std::string ConversionFnKind;
   
   MatchableInfo(const CodeGenInstruction &CGI)
-    : TheDef(CGI.TheDef), DefRec(&CGI),
-      TheOperandList(CGI.Operands), AsmString(CGI.AsmString) {
+    : TheDef(CGI.TheDef), DefRec(&CGI), AsmString(CGI.AsmString) {
   }
 
   MatchableInfo(const CodeGenInstAlias *Alias)
-    : TheDef(Alias->TheDef), DefRec(Alias), TheOperandList(Alias->Operands),
-      AsmString(Alias->AsmString) {
+    : TheDef(Alias->TheDef), DefRec(Alias), AsmString(Alias->AsmString) {
   }
   
   void Initialize(const AsmMatcherInfo &Info,
@@ -1128,7 +1128,7 @@ BuildInstructionOperandReference(MatchableInfo *II,
   const CodeGenInstruction &CGI = *II->DefRec.get<const CodeGenInstruction*>();
   const CGIOperandList &Operands = CGI.Operands;
   
-  // Map this token to an operand. FIXME: Move elsewhere.
+  // Map this token to an operand.
   unsigned Idx;
   if (!Operands.hasOperandNamed(OperandName, Idx))
     throw TGError(II->TheDef->getLoc(), "error: unable to find operand: '" +
@@ -1171,6 +1171,8 @@ void AsmMatcherInfo::BuildAliasOperandReference(MatchableInfo *II,
   // Set up the operand class.
   for (unsigned i = 0, e = CGA.ResultOperands.size(); i != e; ++i)
     if (CGA.ResultOperands[i].Name == OperandName) {
+      // It's safe to go with the first one we find, because CodeGenInstAlias
+      // validates that all operands with the same name have the same record.
       Op.Class = getOperandClass(CGA.ResultInst->Operands[i]);
       Op.SrcOpName = OperandName;
       return;
@@ -1181,8 +1183,12 @@ void AsmMatcherInfo::BuildAliasOperandReference(MatchableInfo *II,
 }
 
 void MatchableInfo::BuildResultOperands() {
-  for (unsigned i = 0, e = TheOperandList.size(); i != e; ++i) {
-    const CGIOperandList::OperandInfo &OpInfo = TheOperandList[i];
+  const CodeGenInstruction *ResultInst = getResultInst();
+  
+  // Loop over all operands of the result instruction, determining how to
+  // populate them.
+  for (unsigned i = 0, e = ResultInst->Operands.size(); i != e; ++i) {
+    const CGIOperandList::OperandInfo &OpInfo = ResultInst->Operands[i];
 
     // If this is a tied operand, just copy from the previously handled operand.
     int TiedOp = OpInfo.getTiedRegister();
@@ -1794,15 +1800,9 @@ void AsmMatcherEmitter::run(raw_ostream &OS) {
     MatchableInfo &II = **it;
 
 
-    const CodeGenInstruction *ResultInst;
-    if (II.DefRec.is<const CodeGenInstruction*>())
-      ResultInst = II.DefRec.get<const CodeGenInstruction*>();
-    else
-      ResultInst = II.DefRec.get<const CodeGenInstAlias*>()->ResultInst;
-    
-    OS << "  { " << Target.getName() << "::" << ResultInst->TheDef->getName()
-    << ", \"" << II.Mnemonic << "\""
-    << ", " << II.ConversionFnKind << ", { ";
+    OS << "  { " << Target.getName() << "::"
+       << II.getResultInst()->TheDef->getName() << ", \"" << II.Mnemonic << "\""
+       << ", " << II.ConversionFnKind << ", { ";
     for (unsigned i = 0, e = II.AsmOperands.size(); i != e; ++i) {
       MatchableInfo::AsmOperand &Op = II.AsmOperands[i];
 

llvm/utils/TableGen/CodeGenInstruction.cpp

@@ -389,10 +389,8 @@ FlattenAsmStringVariants(StringRef Cur, unsigned Variant) {
 /// CodeGenInstAlias Implementation
 //===----------------------------------------------------------------------===//
 
-CodeGenInstAlias::CodeGenInstAlias(Record *R, CodeGenTarget &T)
-  : TheDef(R), Operands(R) {
+CodeGenInstAlias::CodeGenInstAlias(Record *R, CodeGenTarget &T) : TheDef(R) {
   AsmString = R->getValueAsString("AsmString");
-
   Result = R->getValueAsDag("ResultInst");
 
   // Verify that the root of the result is an instruction.

llvm/utils/TableGen/CodeGenInstruction.h

@@ -258,10 +258,6 @@ namespace llvm {
     /// instruction.
     std::string AsmString;
     
-    /// Operands - This is information about the (ins) and (outs) list specified
-    /// to the alias.
-    CGIOperandList Operands;
-    
     /// Result - The result instruction.
     DagInit *Result;