[MC] Move deprecation infos from MCTargetDesc to MCInstrInfo

This allows emitting it only when the feature is used by a target.
Shrinks Release+Asserts clang by 900k.

llvm/include/llvm/MC/MCInstrDesc.h

@@ -197,15 +197,6 @@ class MCInstrDesc {
   const MCPhysReg *ImplicitUses; // Registers implicitly read by this instr
   const MCPhysReg *ImplicitDefs; // Registers implicitly defined by this instr
   const MCOperandInfo *OpInfo;   // 'NumOperands' entries about operands
-  // Subtarget feature that this is deprecated on, if any
-  // -1 implies this is not deprecated by any single feature. It may still be
-  // deprecated due to a "complex" reason, below.
-  int64_t DeprecatedFeature;
-
-  // A complex method to determine if a certain instruction is deprecated or
-  // not, and return the reason for deprecation.
-  bool (*ComplexDeprecationInfo)(MCInst &, const MCSubtargetInfo &,
-                                 std::string &);
 
   /// Returns the value of the specific constraint if
   /// it is set. Returns -1 if it is not set.
@@ -219,11 +210,6 @@ class MCInstrDesc {
     return -1;
   }
 
-  /// Returns true if a certain instruction is deprecated and if so
-  /// returns the reason in \p Info.
-  bool getDeprecatedInfo(MCInst &MI, const MCSubtargetInfo &STI,
-                         std::string &Info) const;
-
   /// Return the opcode number for this descriptor.
   unsigned getOpcode() const { return Opcode; }
 

llvm/include/llvm/MC/MCInstrInfo.h

@@ -21,19 +21,35 @@ namespace llvm {
 //---------------------------------------------------------------------------
 /// Interface to description of machine instruction set.
 class MCInstrInfo {
+public:
+  using ComplexDeprecationPredicate = bool (*)(MCInst &,
+                                               const MCSubtargetInfo &,
+                                               std::string &);
+
+private:
   const MCInstrDesc *Desc;          // Raw array to allow static init'n
   const unsigned *InstrNameIndices; // Array for name indices in InstrNameData
   const char *InstrNameData;        // Instruction name string pool
+  // Subtarget feature that an instruction is deprecated on, if any
+  // -1 implies this is not deprecated by any single feature. It may still be
+  // deprecated due to a "complex" reason, below.
+  const uint8_t *DeprecatedFeatures;
+  // A complex method to determine if a certain instruction is deprecated or
+  // not, and return the reason for deprecation.
+  const ComplexDeprecationPredicate *ComplexDeprecationInfos;
   unsigned NumOpcodes;              // Number of entries in the desc array
 
 public:
   /// Initialize MCInstrInfo, called by TableGen auto-generated routines.
   /// *DO NOT USE*.
   void InitMCInstrInfo(const MCInstrDesc *D, const unsigned *NI, const char *ND,
-                       unsigned NO) {
+                       const uint8_t *DF,
+                       const ComplexDeprecationPredicate *CDI, unsigned NO) {
     Desc = D;
     InstrNameIndices = NI;
     InstrNameData = ND;
+    DeprecatedFeatures = DF;
+    ComplexDeprecationInfos = CDI;
     NumOpcodes = NO;
   }
 
@@ -51,6 +67,11 @@ class MCInstrInfo {
     assert(Opcode < NumOpcodes && "Invalid opcode!");
     return StringRef(&InstrNameData[InstrNameIndices[Opcode]]);
   }
+
+  /// Returns true if a certain instruction is deprecated and if so
+  /// returns the reason in \p Info.
+  bool getDeprecatedInfo(MCInst &MI, const MCSubtargetInfo &STI,
+                         std::string &Info) const;
 };
 
 } // End llvm namespace

llvm/lib/MC/CMakeLists.txt

@@ -23,6 +23,7 @@ add_llvm_component_library(LLVMMC
   MCInstPrinter.cpp
   MCInstrAnalysis.cpp
   MCInstrDesc.cpp
+  MCInstrInfo.cpp
   MCLabel.cpp
   MCLinkerOptimizationHint.cpp
   MCMachOStreamer.cpp

llvm/lib/MC/MCInstrDesc.cpp

@@ -18,17 +18,6 @@
 
 using namespace llvm;
 
-bool MCInstrDesc::getDeprecatedInfo(MCInst &MI, const MCSubtargetInfo &STI,
-                                    std::string &Info) const {
-  if (ComplexDeprecationInfo)
-    return ComplexDeprecationInfo(MI, STI, Info);
-  if (DeprecatedFeature != -1 && STI.getFeatureBits()[DeprecatedFeature]) {
-    // FIXME: it would be nice to include the subtarget feature here.
-    Info = "deprecated";
-    return true;
-  }
-  return false;
-}
 bool MCInstrDesc::mayAffectControlFlow(const MCInst &MI,
                                        const MCRegisterInfo &RI) const {
   if (isBranch() || isCall() || isReturn() || isIndirectBranch())

llvm/lib/MC/MCInstrInfo.cpp

@@ -0,0 +1,27 @@
+//===- lib/MC/MCInstrInfo.cpp - Target Instruction Info -------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/MC/MCInstrInfo.h"
+#include "llvm/MC/MCInst.h"
+#include "llvm/MC/MCSubtargetInfo.h"
+
+using namespace llvm;
+
+bool MCInstrInfo::getDeprecatedInfo(MCInst &MI, const MCSubtargetInfo &STI,
+                                    std::string &Info) const {
+  unsigned Opcode = MI.getOpcode();
+  if (ComplexDeprecationInfos && ComplexDeprecationInfos[Opcode])
+    return ComplexDeprecationInfos[Opcode](MI, STI, Info);
+  if (DeprecatedFeatures && DeprecatedFeatures[Opcode] != uint8_t(-1U) &&
+      STI.getFeatureBits()[DeprecatedFeatures[Opcode]]) {
+    // FIXME: it would be nice to include the subtarget feature here.
+    Info = "deprecated";
+    return true;
+  }
+  return false;
+}

llvm/unittests/CodeGen/MachineInstrTest.cpp

@@ -50,8 +50,8 @@ TEST(IsIdenticalToTest, DifferentDefs) {
       {0, 0, MCOI::OPERAND_REGISTER, 0},
       {0, 1 << MCOI::OptionalDef, MCOI::OPERAND_REGISTER, 0}};
   MCInstrDesc MCID = {
-      0, NumOps,  NumDefs, 0,      0, 1ULL << MCID::HasOptionalDef,
-      0, nullptr, nullptr, OpInfo, 0, nullptr};
+      0, NumOps,  NumDefs, 0,     0, 1ULL << MCID::HasOptionalDef,
+      0, nullptr, nullptr, OpInfo};
 
   // Create two MIs with different virtual reg defs and the same uses.
   unsigned VirtualDef1 = -42; // The value doesn't matter, but the sign does.
@@ -121,8 +121,8 @@ TEST(MachineInstrExpressionTraitTest, IsEqualAgreesWithGetHashValue) {
       {0, 0, MCOI::OPERAND_REGISTER, 0},
       {0, 1 << MCOI::OptionalDef, MCOI::OPERAND_REGISTER, 0}};
   MCInstrDesc MCID = {
-      0, NumOps,  NumDefs, 0,      0, 1ULL << MCID::HasOptionalDef,
-      0, nullptr, nullptr, OpInfo, 0, nullptr};
+      0, NumOps,  NumDefs, 0,     0, 1ULL << MCID::HasOptionalDef,
+      0, nullptr, nullptr, OpInfo};
 
   // Define a series of instructions with different kinds of operands and make
   // sure that the hash function is consistent with isEqual for various
@@ -196,8 +196,7 @@ TEST(MachineInstrPrintingTest, DebugLocPrinting) {
   auto MF = createMachineFunction(Ctx, Mod);
 
   MCOperandInfo OpInfo{0, 0, MCOI::OPERAND_REGISTER, 0};
-  MCInstrDesc MCID = {0, 1,       1,       0,       0, 0,
-                      0, nullptr, nullptr, &OpInfo, 0, nullptr};
+  MCInstrDesc MCID = {0, 1, 1, 0, 0, 0, 0, nullptr, nullptr, &OpInfo};
 
   DIFile *DIF = DIFile::getDistinct(Ctx, "filename", "");
   DISubprogram *DIS = DISubprogram::getDistinct(
@@ -224,8 +223,7 @@ TEST(MachineInstrSpan, DistanceBegin) {
   auto MF = createMachineFunction(Ctx, Mod);
   auto MBB = MF->CreateMachineBasicBlock();
 
-  MCInstrDesc MCID = {0, 0,       0,       0,       0, 0,
-                      0, nullptr, nullptr, nullptr, 0, nullptr};
+  MCInstrDesc MCID = {0, 0, 0, 0, 0, 0, 0, nullptr, nullptr, nullptr};
 
   auto MII = MBB->begin();
   MachineInstrSpan MIS(MII, MBB);
@@ -242,8 +240,7 @@ TEST(MachineInstrSpan, DistanceEnd) {
   auto MF = createMachineFunction(Ctx, Mod);
   auto MBB = MF->CreateMachineBasicBlock();
 
-  MCInstrDesc MCID = {0, 0,       0,       0,       0, 0,
-                      0, nullptr, nullptr, nullptr, 0, nullptr};
+  MCInstrDesc MCID = {0, 0, 0, 0, 0, 0, 0, nullptr, nullptr, nullptr};
 
   auto MII = MBB->end();
   MachineInstrSpan MIS(MII, MBB);
@@ -258,8 +255,7 @@ TEST(MachineInstrExtraInfo, AddExtraInfo) {
   LLVMContext Ctx;
   Module Mod("Module", Ctx);
   auto MF = createMachineFunction(Ctx, Mod);
-  MCInstrDesc MCID = {0, 0,       0,       0,       0, 0,
-                      0, nullptr, nullptr, nullptr, 0, nullptr};
+  MCInstrDesc MCID = {0, 0, 0, 0, 0, 0, 0, nullptr, nullptr, nullptr};
 
   auto MI = MF->CreateMachineInstr(MCID, DebugLoc());
   auto MAI = MCAsmInfo();
@@ -306,8 +302,7 @@ TEST(MachineInstrExtraInfo, ChangeExtraInfo) {
   LLVMContext Ctx;
   Module Mod("Module", Ctx);
   auto MF = createMachineFunction(Ctx, Mod);
-  MCInstrDesc MCID = {0, 0,       0,       0,       0, 0,
-                      0, nullptr, nullptr, nullptr, 0, nullptr};
+  MCInstrDesc MCID = {0, 0, 0, 0, 0, 0, 0, nullptr, nullptr, nullptr};
 
   auto MI = MF->CreateMachineInstr(MCID, DebugLoc());
   auto MAI = MCAsmInfo();
@@ -344,8 +339,7 @@ TEST(MachineInstrExtraInfo, RemoveExtraInfo) {
   LLVMContext Ctx;
   Module Mod("Module", Ctx);
   auto MF = createMachineFunction(Ctx, Mod);
-  MCInstrDesc MCID = {0, 0,       0,       0,       0, 0,
-                      0, nullptr, nullptr, nullptr, 0, nullptr};
+  MCInstrDesc MCID = {0, 0, 0, 0, 0, 0, 0, nullptr, nullptr, nullptr};
 
   auto MI = MF->CreateMachineInstr(MCID, DebugLoc());
   auto MAI = MCAsmInfo();

llvm/utils/TableGen/AsmMatcherEmitter.cpp

@@ -3863,7 +3863,7 @@ void AsmMatcherEmitter::run(raw_ostream &OS) {
     OS << "    std::string Info;\n";
     OS << "    if (!getParser().getTargetParser().\n";
     OS << "        getTargetOptions().MCNoDeprecatedWarn &&\n";
-    OS << "        MII.get(Inst.getOpcode()).getDeprecatedInfo(Inst, getSTI(), Info)) {\n";
+    OS << "        MII.getDeprecatedInfo(Inst, getSTI(), Info)) {\n";
     OS << "      SMLoc Loc = ((" << Target.getName()
        << "Operand&)*Operands[0]).getStartLoc();\n";
     OS << "      getParser().Warning(Loc, Info, None);\n";

llvm/utils/TableGen/InstrInfoEmitter.cpp

@@ -581,15 +581,66 @@ void InstrInfoEmitter::run(raw_ostream &OS) {
     OS << InstrNames.get(std::string(Inst->TheDef->getName())) << "U, ";
     ++Num;
   }
-
   OS << "\n};\n\n";
 
+  bool HasDeprecationFeatures =
+      llvm::any_of(NumberedInstructions, [](const CodeGenInstruction *Inst) {
+        return !Inst->HasComplexDeprecationPredicate &&
+               !Inst->DeprecatedReason.empty();
+      });
+  if (HasDeprecationFeatures) {
+    OS << "extern const uint8_t " << TargetName
+       << "InstrDeprecationFeatures[] = {";
+    Num = 0;
+    for (const CodeGenInstruction *Inst : NumberedInstructions) {
+      if (Num % 8 == 0)
+        OS << "\n    ";
+      if (!Inst->HasComplexDeprecationPredicate &&
+          !Inst->DeprecatedReason.empty())
+        OS << Target.getInstNamespace() << "::" << Inst->DeprecatedReason
+           << ", ";
+      else
+        OS << "uint8_t(-1), ";
+      ++Num;
+    }
+    OS << "\n};\n\n";
+  }
+
+  bool HasComplexDeprecationInfos =
+      llvm::any_of(NumberedInstructions, [](const CodeGenInstruction *Inst) {
+        return Inst->HasComplexDeprecationPredicate;
+      });
+  if (HasComplexDeprecationInfos) {
+    OS << "extern const MCInstrInfo::ComplexDeprecationPredicate " << TargetName
+       << "InstrComplexDeprecationInfos[] = {";
+    Num = 0;
+    for (const CodeGenInstruction *Inst : NumberedInstructions) {
+      if (Num % 8 == 0)
+        OS << "\n    ";
+      if (Inst->HasComplexDeprecationPredicate)
+        // Emit a function pointer to the complex predicate method.
+        OS << "&get" << Inst->DeprecatedReason << "DeprecationInfo, ";
+      else
+        OS << "nullptr, ";
+      ++Num;
+    }
+    OS << "\n};\n\n";
+  }
+
   // MCInstrInfo initialization routine.
   OS << "static inline void Init" << TargetName
      << "MCInstrInfo(MCInstrInfo *II) {\n";
-  OS << "  II->InitMCInstrInfo(" << TargetName << "Insts, "
-     << TargetName << "InstrNameIndices, " << TargetName << "InstrNameData, "
-     << NumberedInstructions.size() << ");\n}\n\n";
+  OS << "  II->InitMCInstrInfo(" << TargetName << "Insts, " << TargetName
+     << "InstrNameIndices, " << TargetName << "InstrNameData, ";
+  if (HasDeprecationFeatures)
+    OS << TargetName << "InstrDeprecationFeatures, ";
+  else
+    OS << "nullptr, ";
+  if (HasComplexDeprecationInfos)
+    OS << TargetName << "InstrComplexDeprecationInfos, ";
+  else
+    OS << "nullptr, ";
+  OS << NumberedInstructions.size() << ");\n}\n\n";
 
   OS << "} // end namespace llvm\n";
 
@@ -629,12 +680,28 @@ void InstrInfoEmitter::run(raw_ostream &OS) {
   OS << "extern const MCInstrDesc " << TargetName << "Insts[];\n";
   OS << "extern const unsigned " << TargetName << "InstrNameIndices[];\n";
   OS << "extern const char " << TargetName << "InstrNameData[];\n";
+  if (HasDeprecationFeatures)
+    OS << "extern const uint8_t " << TargetName
+       << "InstrDeprecationFeatures[];\n";
+  if (HasComplexDeprecationInfos)
+    OS << "extern const MCInstrInfo::ComplexDeprecationPredicate " << TargetName
+       << "InstrComplexDeprecationInfos[];\n";
   OS << ClassName << "::" << ClassName
-     << "(int CFSetupOpcode, int CFDestroyOpcode, int CatchRetOpcode, int ReturnOpcode)\n"
-     << "  : TargetInstrInfo(CFSetupOpcode, CFDestroyOpcode, CatchRetOpcode, ReturnOpcode) {\n"
+     << "(int CFSetupOpcode, int CFDestroyOpcode, int CatchRetOpcode, int "
+        "ReturnOpcode)\n"
+     << "  : TargetInstrInfo(CFSetupOpcode, CFDestroyOpcode, CatchRetOpcode, "
+        "ReturnOpcode) {\n"
      << "  InitMCInstrInfo(" << TargetName << "Insts, " << TargetName
-     << "InstrNameIndices, " << TargetName << "InstrNameData, "
-     << NumberedInstructions.size() << ");\n}\n";
+     << "InstrNameIndices, " << TargetName << "InstrNameData, ";
+  if (HasDeprecationFeatures)
+    OS << TargetName << "InstrDeprecationFeatures, ";
+  else
+    OS << "nullptr, ";
+  if (HasComplexDeprecationInfos)
+    OS << TargetName << "InstrComplexDeprecationInfos, ";
+  else
+    OS << "nullptr, ";
+  OS << NumberedInstructions.size() << ");\n}\n";
   OS << "} // end namespace llvm\n";
 
   OS << "#endif // GET_INSTRINFO_CTOR_DTOR\n\n";
@@ -745,18 +812,6 @@ void InstrInfoEmitter::emitRecord(const CodeGenInstruction &Inst, unsigned Num,
   else
     OS << "OperandInfo" << OpInfo.find(OperandInfo)->second;
 
-  if (Inst.HasComplexDeprecationPredicate)
-    // Emit a function pointer to the complex predicate method.
-    OS << ", -1 "
-       << ",&get" << Inst.DeprecatedReason << "DeprecationInfo";
-  else if (!Inst.DeprecatedReason.empty())
-    // Emit the Subtarget feature.
-    OS << ", " << Target.getInstNamespace() << "::" << Inst.DeprecatedReason
-       << " ,nullptr";
-  else
-    // Instruction isn't deprecated.
-    OS << ", -1 ,nullptr";
-
   OS << " },  // Inst #" << Num << " = " << Inst.TheDef->getName() << "\n";
 }