Merge pull request #866 from jbj/ir-TInstruction-normalize

C++: Normalize TInstruction

cpp/ql/src/semmle/code/cpp/ir/implementation/aliased_ssa/Instruction.qll

@@ -10,8 +10,6 @@ import semmle.code.cpp.ir.implementation.Opcode
 private import semmle.code.cpp.ir.implementation.Opcode
 private import semmle.code.cpp.ir.internal.OperandTag
 
-class InstructionTag = Construction::InstructionTagType;
-
 module InstructionSanity {
   /**
    * Holds if the instruction `instr` should be expected to have an operand
@@ -211,17 +209,6 @@ module InstructionSanity {
  * Represents a single operation in the IR.
  */
 class Instruction extends Construction::TInstruction {
-  Opcode opcode;
-  Locatable ast;
-  InstructionTag instructionTag;
-  Type resultType;
-  FunctionIR funcIR;
-  boolean glvalue;
-
-  Instruction() {
-    this = Construction::MkInstruction(funcIR, opcode, ast, instructionTag, resultType, glvalue)
-  }
-
   final string toString() {
     result = getOpcode().toString() + ": " + getAST().toString()
   }
@@ -244,9 +231,9 @@ class Instruction extends Construction::TInstruction {
    */
   final string getOperationString() {
     if exists(getImmediateString()) then
-      result = getOperationPrefix() + opcode.toString() + "[" + getImmediateString() + "]"
+      result = getOperationPrefix() + getOpcode().toString() + "[" + getImmediateString() + "]"
     else
-      result = getOperationPrefix() + opcode.toString()
+      result = getOperationPrefix() + getOpcode().toString()
   }
 
   /**
@@ -264,7 +251,7 @@ class Instruction extends Construction::TInstruction {
   }
 
   private string getResultPrefix() {
-    if resultType instanceof VoidType then
+    if getResultType() instanceof VoidType then
       result = "v"
     else if hasMemoryResult() then
       if isResultModeled() then
@@ -309,8 +296,8 @@ class Instruction extends Construction::TInstruction {
 
   private string getResultTypeString() {
     exists(string valcat |
-      valcat = getValueCategoryString(resultType.toString()) and
-      if (resultType instanceof UnknownType and
+      valcat = getValueCategoryString(getResultType().toString()) and
+      if (getResultType() instanceof UnknownType and
           not isGLValue() and
           exists(getResultSize())) then (
         result = valcat + "[" + getResultSize().toString() + "]"
@@ -378,28 +365,28 @@ class Instruction extends Construction::TInstruction {
    * Gets the function that contains this instruction.
    */
   final Function getFunction() {
-    result = funcIR.getFunction()
+    result = getFunctionIR().getFunction()
   }
 
   /**
    * Gets the FunctionIR object that contains the IR for this instruction.
    */
   final FunctionIR getFunctionIR() {
-    result = funcIR
+    result = Construction::getInstructionEnclosingFunctionIR(this)
   }
 
   /**
    * Gets the AST that caused this instruction to be generated.
    */
   final Locatable getAST() {
-    result = ast
+    result = Construction::getInstructionAST(this)
   }
 
   /**
    * Gets the location of the source code for this instruction.
    */
   final Location getLocation() {
-    result = ast.getLocation()
+    result = getAST().getLocation()
   }
 
   /**
@@ -421,7 +408,7 @@ class Instruction extends Construction::TInstruction {
    * instruction does not produce a result, its result type will be `VoidType`.
    */
   final Type getResultType() {
-    result = resultType
+    Construction::instructionHasType(this, result, _)
   }
 
   /**
@@ -443,7 +430,7 @@ class Instruction extends Construction::TInstruction {
    * the integer value loaded from variable `x`.
    */
   final predicate isGLValue() {
-    glvalue = true
+    Construction::instructionHasType(this, _, true)
   }
 
   /**
@@ -460,10 +447,10 @@ class Instruction extends Construction::TInstruction {
         result = nullptr.getSize()
       )
     )
-    else if resultType instanceof UnknownType then
+    else if getResultType() instanceof UnknownType then
       result = Construction::getInstructionResultSize(this)
     else (
-      result = resultType.getSize()
+      result = getResultType().getSize()
     )
   }
 
@@ -471,11 +458,7 @@ class Instruction extends Construction::TInstruction {
    * Gets the opcode that specifies the operation performed by this instruction.
    */
   final Opcode getOpcode() {
-    result = opcode
-  }
-
-  final InstructionTag getTag() {
-    result = instructionTag
+    result = Construction::getInstructionOpcode(this)
   }
 
   /**
@@ -644,19 +627,19 @@ class ConstantValueInstruction extends Instruction {
 
 class EnterFunctionInstruction extends Instruction {
   EnterFunctionInstruction() {
-    opcode instanceof Opcode::EnterFunction
+    getOpcode() instanceof Opcode::EnterFunction
   }
 }
 
 class VariableAddressInstruction extends VariableInstruction {
   VariableAddressInstruction() {
-    opcode instanceof Opcode::VariableAddress
+    getOpcode() instanceof Opcode::VariableAddress
   }
 }
 
 class InitializeParameterInstruction extends VariableInstruction {
   InitializeParameterInstruction() {
-    opcode instanceof Opcode::InitializeParameter
+    getOpcode() instanceof Opcode::InitializeParameter
   }
 
   final Parameter getParameter() {
@@ -673,13 +656,13 @@ class InitializeParameterInstruction extends VariableInstruction {
  */
 class InitializeThisInstruction extends Instruction {
   InitializeThisInstruction() {
-    opcode instanceof Opcode::InitializeThis
+    getOpcode() instanceof Opcode::InitializeThis
   }
 }
 
 class FieldAddressInstruction extends FieldInstruction {
   FieldAddressInstruction() {
-    opcode instanceof Opcode::FieldAddress
+    getOpcode() instanceof Opcode::FieldAddress
   }
 
   final Instruction getObjectAddress() {
@@ -689,7 +672,7 @@ class FieldAddressInstruction extends FieldInstruction {
 
 class UninitializedInstruction extends VariableInstruction {
   UninitializedInstruction() {
-    opcode instanceof Opcode::Uninitialized
+    getOpcode() instanceof Opcode::Uninitialized
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -706,25 +689,25 @@ class UninitializedInstruction extends VariableInstruction {
 
 class NoOpInstruction extends Instruction {
   NoOpInstruction() {
-    opcode instanceof Opcode::NoOp
+    getOpcode() instanceof Opcode::NoOp
   }
 }
 
 class ReturnInstruction extends Instruction {
   ReturnInstruction() {
-    opcode instanceof ReturnOpcode
+    getOpcode() instanceof ReturnOpcode
   }
 }
 
 class ReturnVoidInstruction extends ReturnInstruction {
   ReturnVoidInstruction() {
-    opcode instanceof Opcode::ReturnVoid
+    getOpcode() instanceof Opcode::ReturnVoid
   }
 }
 
 class ReturnValueInstruction extends ReturnInstruction {
   ReturnValueInstruction() {
-    opcode instanceof Opcode::ReturnValue
+    getOpcode() instanceof Opcode::ReturnValue
   }
 
   final Instruction getReturnValue() {
@@ -734,7 +717,7 @@ class ReturnValueInstruction extends ReturnInstruction {
 
 class CopyInstruction extends Instruction {
   CopyInstruction() {
-    opcode instanceof CopyOpcode
+    getOpcode() instanceof CopyOpcode
   }
 
   final Instruction getSourceValue() {
@@ -744,13 +727,13 @@ class CopyInstruction extends Instruction {
 
 class CopyValueInstruction extends CopyInstruction {
   CopyValueInstruction() {
-    opcode instanceof Opcode::CopyValue
+    getOpcode() instanceof Opcode::CopyValue
   }
 }
 
 class LoadInstruction extends CopyInstruction {
   LoadInstruction() {
-    opcode instanceof Opcode::Load
+    getOpcode() instanceof Opcode::Load
   }
 
   final Instruction getSourceAddress() {
@@ -760,7 +743,7 @@ class LoadInstruction extends CopyInstruction {
 
 class StoreInstruction extends CopyInstruction {
   StoreInstruction() {
-    opcode instanceof Opcode::Store
+    getOpcode() instanceof Opcode::Store
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -774,7 +757,7 @@ class StoreInstruction extends CopyInstruction {
 
 class ConditionalBranchInstruction extends Instruction {
   ConditionalBranchInstruction() {
-    opcode instanceof Opcode::ConditionalBranch
+    getOpcode() instanceof Opcode::ConditionalBranch
   }
 
   final Instruction getCondition() {
@@ -792,25 +775,25 @@ class ConditionalBranchInstruction extends Instruction {
 
 class ExitFunctionInstruction extends Instruction {
   ExitFunctionInstruction() {
-    opcode instanceof Opcode::ExitFunction
+    getOpcode() instanceof Opcode::ExitFunction
   }
 }
 
 class ConstantInstruction extends ConstantValueInstruction {
   ConstantInstruction() {
-    opcode instanceof Opcode::Constant
+    getOpcode() instanceof Opcode::Constant
   }
 }
 
 class IntegerConstantInstruction extends ConstantInstruction {
   IntegerConstantInstruction() {
-    resultType instanceof IntegralType
+    getResultType() instanceof IntegralType
   }
 }
 
 class FloatConstantInstruction extends ConstantInstruction {
   FloatConstantInstruction() {
-    resultType instanceof FloatingPointType
+    getResultType() instanceof FloatingPointType
   }
 }
 
@@ -832,7 +815,7 @@ class StringConstantInstruction extends Instruction {
 
 class BinaryInstruction extends Instruction {
   BinaryInstruction() {
-    opcode instanceof BinaryOpcode
+    getOpcode() instanceof BinaryOpcode
   }
 
   final Instruction getLeftOperand() {
@@ -855,67 +838,67 @@ class BinaryInstruction extends Instruction {
 
 class AddInstruction extends BinaryInstruction {
   AddInstruction() {
-    opcode instanceof Opcode::Add
+    getOpcode() instanceof Opcode::Add
   }
 }
 
 class SubInstruction extends BinaryInstruction {
   SubInstruction() {
-    opcode instanceof Opcode::Sub
+    getOpcode() instanceof Opcode::Sub
   }
 }
 
 class MulInstruction extends BinaryInstruction {
   MulInstruction() {
-    opcode instanceof Opcode::Mul
+    getOpcode() instanceof Opcode::Mul
   }
 }
 
 class DivInstruction extends BinaryInstruction {
   DivInstruction() {
-    opcode instanceof Opcode::Div
+    getOpcode() instanceof Opcode::Div
   }
 }
 
 class RemInstruction extends BinaryInstruction {
   RemInstruction() {
-    opcode instanceof Opcode::Rem
+    getOpcode() instanceof Opcode::Rem
   }
 }
 
 class NegateInstruction extends UnaryInstruction {
   NegateInstruction() {
-    opcode instanceof Opcode::Negate
+    getOpcode() instanceof Opcode::Negate
   }
 }
 
 class BitAndInstruction extends BinaryInstruction {
   BitAndInstruction() {
-    opcode instanceof Opcode::BitAnd
+    getOpcode() instanceof Opcode::BitAnd
   }
 }
 
 class BitOrInstruction extends BinaryInstruction {
   BitOrInstruction() {
-    opcode instanceof Opcode::BitOr
+    getOpcode() instanceof Opcode::BitOr
   }
 }
 
 class BitXorInstruction extends BinaryInstruction {
   BitXorInstruction() {
-    opcode instanceof Opcode::BitXor
+    getOpcode() instanceof Opcode::BitXor
   }
 }
 
 class ShiftLeftInstruction extends BinaryInstruction {
   ShiftLeftInstruction() {
-    opcode instanceof Opcode::ShiftLeft
+    getOpcode() instanceof Opcode::ShiftLeft
   }
 }
 
 class ShiftRightInstruction extends BinaryInstruction {
   ShiftRightInstruction() {
-    opcode instanceof Opcode::ShiftRight
+    getOpcode() instanceof Opcode::ShiftRight
   }
 }
 
@@ -923,7 +906,7 @@ class PointerArithmeticInstruction extends BinaryInstruction {
   int elementSize;
 
   PointerArithmeticInstruction() {
-    opcode instanceof PointerArithmeticOpcode and
+    getOpcode() instanceof PointerArithmeticOpcode and
     elementSize = Construction::getInstructionElementSize(this)
   }
 
@@ -938,31 +921,31 @@ class PointerArithmeticInstruction extends BinaryInstruction {
 
 class PointerOffsetInstruction extends PointerArithmeticInstruction {
   PointerOffsetInstruction() {
-    opcode instanceof PointerOffsetOpcode
+    getOpcode() instanceof PointerOffsetOpcode
   }
 }
 
 class PointerAddInstruction extends PointerOffsetInstruction {
   PointerAddInstruction() {
-    opcode instanceof Opcode::PointerAdd
+    getOpcode() instanceof Opcode::PointerAdd
   }
 }
 
 class PointerSubInstruction extends PointerOffsetInstruction {
   PointerSubInstruction() {
-    opcode instanceof Opcode::PointerSub
+    getOpcode() instanceof Opcode::PointerSub
   }
 }
 
 class PointerDiffInstruction extends PointerArithmeticInstruction {
   PointerDiffInstruction() {
-    opcode instanceof Opcode::PointerDiff
+    getOpcode() instanceof Opcode::PointerDiff
   }
 }
 
 class UnaryInstruction extends Instruction {
   UnaryInstruction() {
-    opcode instanceof UnaryOpcode
+    getOpcode() instanceof UnaryOpcode
   }
 
   final Instruction getOperand() {
@@ -972,7 +955,7 @@ class UnaryInstruction extends Instruction {
 
 class ConvertInstruction extends UnaryInstruction {
   ConvertInstruction() {
-    opcode instanceof Opcode::Convert
+    getOpcode() instanceof Opcode::Convert
   }
 }
 
@@ -1024,7 +1007,7 @@ class InheritanceConversionInstruction extends UnaryInstruction {
  */
 class ConvertToBaseInstruction extends InheritanceConversionInstruction {
   ConvertToBaseInstruction() {
-    opcode instanceof Opcode::ConvertToBase
+    getOpcode() instanceof Opcode::ConvertToBase
   }
 }
 
@@ -1034,7 +1017,7 @@ class ConvertToBaseInstruction extends InheritanceConversionInstruction {
  */
 class ConvertToVirtualBaseInstruction extends InheritanceConversionInstruction {
   ConvertToVirtualBaseInstruction() {
-    opcode instanceof Opcode::ConvertToVirtualBase
+    getOpcode() instanceof Opcode::ConvertToVirtualBase
   }
 }
 
@@ -1044,37 +1027,37 @@ class ConvertToVirtualBaseInstruction extends InheritanceConversionInstruction {
  */
 class ConvertToDerivedInstruction extends InheritanceConversionInstruction {
   ConvertToDerivedInstruction() {
-    opcode instanceof Opcode::ConvertToDerived
+    getOpcode() instanceof Opcode::ConvertToDerived
   }
 }
 
 class BitComplementInstruction extends UnaryInstruction {
   BitComplementInstruction() {
-    opcode instanceof Opcode::BitComplement
+    getOpcode() instanceof Opcode::BitComplement
   }
 }
 
 class LogicalNotInstruction extends UnaryInstruction {
   LogicalNotInstruction() {
-    opcode instanceof Opcode::LogicalNot
+    getOpcode() instanceof Opcode::LogicalNot
   }
 }
 
 class CompareInstruction extends BinaryInstruction {
   CompareInstruction() {
-    opcode instanceof CompareOpcode
+    getOpcode() instanceof CompareOpcode
   }
 }
 
 class CompareEQInstruction extends CompareInstruction {
   CompareEQInstruction() {
-    opcode instanceof Opcode::CompareEQ
+    getOpcode() instanceof Opcode::CompareEQ
   }
 }
 
 class CompareNEInstruction extends CompareInstruction {
   CompareNEInstruction() {
-    opcode instanceof Opcode::CompareNE
+    getOpcode() instanceof Opcode::CompareNE
   }
 }
 
@@ -1083,7 +1066,7 @@ class CompareNEInstruction extends CompareInstruction {
  */
 class RelationalInstruction extends CompareInstruction {
   RelationalInstruction() {
-    opcode instanceof RelationalOpcode
+    getOpcode() instanceof RelationalOpcode
   }
 
   /**
@@ -1116,7 +1099,7 @@ class RelationalInstruction extends CompareInstruction {
 
 class CompareLTInstruction extends RelationalInstruction {
   CompareLTInstruction() {
-    opcode instanceof Opcode::CompareLT
+    getOpcode() instanceof Opcode::CompareLT
   }
 
   override Instruction getLesserOperand() {
@@ -1134,7 +1117,7 @@ class CompareLTInstruction extends RelationalInstruction {
 
 class CompareGTInstruction extends RelationalInstruction {
   CompareGTInstruction() {
-    opcode instanceof Opcode::CompareGT
+    getOpcode() instanceof Opcode::CompareGT
   }
 
   override Instruction getLesserOperand() {
@@ -1152,7 +1135,7 @@ class CompareGTInstruction extends RelationalInstruction {
 
 class CompareLEInstruction extends RelationalInstruction {
   CompareLEInstruction() {
-    opcode instanceof Opcode::CompareLE
+    getOpcode() instanceof Opcode::CompareLE
   }
 
   override Instruction getLesserOperand() {
@@ -1170,7 +1153,7 @@ class CompareLEInstruction extends RelationalInstruction {
 
 class CompareGEInstruction extends RelationalInstruction {
   CompareGEInstruction() {
-    opcode instanceof Opcode::CompareGE
+    getOpcode() instanceof Opcode::CompareGE
   }
 
   override Instruction getLesserOperand() {
@@ -1188,7 +1171,7 @@ class CompareGEInstruction extends RelationalInstruction {
 
 class SwitchInstruction extends Instruction {
   SwitchInstruction() {
-    opcode instanceof Opcode::Switch
+    getOpcode() instanceof Opcode::Switch
   }
 
   final Instruction getExpression() {
@@ -1211,7 +1194,7 @@ class SwitchInstruction extends Instruction {
  */
 class CallInstruction extends Instruction {
   CallInstruction() {
-    opcode instanceof Opcode::Call
+    getOpcode() instanceof Opcode::Call
   }
 
   /**
@@ -1254,7 +1237,7 @@ class CallInstruction extends Instruction {
  */
 class SideEffectInstruction extends Instruction {
   SideEffectInstruction() {
-    opcode instanceof SideEffectOpcode
+    getOpcode() instanceof SideEffectOpcode
   }
 
   final Instruction getPrimaryInstruction() {
@@ -1268,7 +1251,7 @@ class SideEffectInstruction extends Instruction {
  */
 class CallSideEffectInstruction extends SideEffectInstruction {
   CallSideEffectInstruction() {
-    opcode instanceof Opcode::CallSideEffect
+    getOpcode() instanceof Opcode::CallSideEffect
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -1282,7 +1265,7 @@ class CallSideEffectInstruction extends SideEffectInstruction {
  */
 class CallReadSideEffectInstruction extends SideEffectInstruction {
   CallReadSideEffectInstruction() {
-    opcode instanceof Opcode::CallReadSideEffect
+    getOpcode() instanceof Opcode::CallReadSideEffect
   }
 }
 
@@ -1291,7 +1274,7 @@ class CallReadSideEffectInstruction extends SideEffectInstruction {
  */
 class IndirectReadSideEffectInstruction extends SideEffectInstruction {
   IndirectReadSideEffectInstruction() {
-    opcode instanceof Opcode::IndirectReadSideEffect
+    getOpcode() instanceof Opcode::IndirectReadSideEffect
   }
 }
 
@@ -1300,7 +1283,7 @@ class IndirectReadSideEffectInstruction extends SideEffectInstruction {
  */
 class BufferReadSideEffectInstruction extends SideEffectInstruction {
   BufferReadSideEffectInstruction() {
-    opcode instanceof Opcode::BufferReadSideEffect
+    getOpcode() instanceof Opcode::BufferReadSideEffect
   }
 }
 
@@ -1309,7 +1292,7 @@ class BufferReadSideEffectInstruction extends SideEffectInstruction {
  */
 class IndirectWriteSideEffectInstruction extends SideEffectInstruction {
   IndirectWriteSideEffectInstruction() {
-    opcode instanceof Opcode::IndirectWriteSideEffect
+    getOpcode() instanceof Opcode::IndirectWriteSideEffect
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -1323,7 +1306,7 @@ class IndirectWriteSideEffectInstruction extends SideEffectInstruction {
  */
 class BufferWriteSideEffectInstruction extends SideEffectInstruction {
   BufferWriteSideEffectInstruction() {
-    opcode instanceof Opcode::BufferWriteSideEffect
+    getOpcode() instanceof Opcode::BufferWriteSideEffect
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -1338,7 +1321,7 @@ class BufferWriteSideEffectInstruction extends SideEffectInstruction {
  */
 class IndirectMayWriteSideEffectInstruction extends SideEffectInstruction {
   IndirectMayWriteSideEffectInstruction() {
-    opcode instanceof Opcode::IndirectMayWriteSideEffect
+    getOpcode() instanceof Opcode::IndirectMayWriteSideEffect
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -1352,7 +1335,7 @@ class IndirectMayWriteSideEffectInstruction extends SideEffectInstruction {
  */
 class BufferMayWriteSideEffectInstruction extends SideEffectInstruction {
   BufferMayWriteSideEffectInstruction() {
-    opcode instanceof Opcode::BufferMayWriteSideEffect
+    getOpcode() instanceof Opcode::BufferMayWriteSideEffect
   }
   override final MemoryAccessKind getResultMemoryAccess() {
     result instanceof BufferMayMemoryAccess
@@ -1364,7 +1347,7 @@ class BufferMayWriteSideEffectInstruction extends SideEffectInstruction {
  */
 class ThrowInstruction extends Instruction {
   ThrowInstruction() {
-    opcode instanceof ThrowOpcode
+    getOpcode() instanceof ThrowOpcode
   }
 }
 
@@ -1373,7 +1356,7 @@ class ThrowInstruction extends Instruction {
  */
 class ThrowValueInstruction extends ThrowInstruction {
   ThrowValueInstruction() {
-    opcode instanceof Opcode::ThrowValue
+    getOpcode() instanceof Opcode::ThrowValue
   }
 
   /**
@@ -1396,7 +1379,7 @@ class ThrowValueInstruction extends ThrowInstruction {
  */
 class ReThrowInstruction extends ThrowInstruction {
   ReThrowInstruction() {
-    opcode instanceof Opcode::ReThrow
+    getOpcode() instanceof Opcode::ReThrow
   }
 }
 
@@ -1405,7 +1388,7 @@ class ReThrowInstruction extends ThrowInstruction {
  */
 class UnwindInstruction extends Instruction {
   UnwindInstruction() {
-    opcode instanceof Opcode::Unwind
+    getOpcode() instanceof Opcode::Unwind
   }
 }
 
@@ -1414,7 +1397,7 @@ class UnwindInstruction extends Instruction {
  */
 class CatchInstruction extends Instruction {
   CatchInstruction() {
-    opcode instanceof CatchOpcode
+    getOpcode() instanceof CatchOpcode
   }
 }
 
@@ -1425,7 +1408,7 @@ class CatchByTypeInstruction extends CatchInstruction {
   Type exceptionType;
 
   CatchByTypeInstruction() {
-    opcode instanceof Opcode::CatchByType and
+    getOpcode() instanceof Opcode::CatchByType and
     exceptionType = Construction::getInstructionExceptionType(this)
   }
 
@@ -1446,13 +1429,13 @@ class CatchByTypeInstruction extends CatchInstruction {
  */
 class CatchAnyInstruction extends CatchInstruction {
   CatchAnyInstruction() {
-    opcode instanceof Opcode::CatchAny
+    getOpcode() instanceof Opcode::CatchAny
   }
 }
 
 class UnmodeledDefinitionInstruction extends Instruction {
   UnmodeledDefinitionInstruction() {
-    opcode instanceof Opcode::UnmodeledDefinition
+    getOpcode() instanceof Opcode::UnmodeledDefinition
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -1465,7 +1448,7 @@ class UnmodeledDefinitionInstruction extends Instruction {
  */
 class AliasedDefinitionInstruction extends Instruction {
   AliasedDefinitionInstruction() {
-    opcode instanceof Opcode::AliasedDefinition
+    getOpcode() instanceof Opcode::AliasedDefinition
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -1475,7 +1458,7 @@ class AliasedDefinitionInstruction extends Instruction {
 
 class UnmodeledUseInstruction extends Instruction {
   UnmodeledUseInstruction() {
-    opcode instanceof Opcode::UnmodeledUse
+    getOpcode() instanceof Opcode::UnmodeledUse
   }
 
   override string getOperandsString() {
@@ -1495,7 +1478,7 @@ class UnmodeledUseInstruction extends Instruction {
  */
 class PhiInstruction extends Instruction {
   PhiInstruction() {
-    opcode instanceof Opcode::Phi
+    getOpcode() instanceof Opcode::Phi
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -1547,7 +1530,7 @@ class PhiInstruction extends Instruction {
  */
 class ChiInstruction extends Instruction {
   ChiInstruction() {
-    opcode instanceof Opcode::Chi
+    getOpcode() instanceof Opcode::Chi
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -1577,7 +1560,7 @@ class ChiInstruction extends Instruction {
  */
 class UnreachedInstruction extends Instruction {
   UnreachedInstruction() {
-    opcode instanceof Opcode::Unreached
+    getOpcode() instanceof Opcode::Unreached
   }
 }
 
@@ -1587,6 +1570,6 @@ class UnreachedInstruction extends Instruction {
  */
 class BuiltInInstruction extends Instruction {
   BuiltInInstruction() {
-    opcode instanceof BuiltInOpcode
+    getOpcode() instanceof BuiltInOpcode
   }
 }

cpp/ql/src/semmle/code/cpp/ir/implementation/aliased_ssa/internal/SSAConstruction.qll

@@ -14,25 +14,6 @@ cached private module Cached {
     result.getFirstInstruction() = getNewInstruction(oldBlock.getFirstInstruction())
   }
 
-  cached newtype TInstructionTag =
-    WrappedInstructionTag(OldInstruction oldInstruction) {
-      not oldInstruction instanceof OldIR::PhiInstruction
-    } or
-    PhiTag(Alias::VirtualVariable vvar, OldBlock block) {
-      hasPhiNode(vvar, block)
-    } or
-    ChiTag(OldInstruction oldInstruction) {
-      not oldInstruction instanceof OldIR::PhiInstruction and
-      hasChiNode(_, oldInstruction)
-    } or
-    UnreachedTag()
-
-  cached class InstructionTagType extends TInstructionTag {
-    cached final string toString() {
-      result = "Tag"
-    }
-  }
-
   cached predicate functionHasIR(Function func) {
     exists(OldIR::FunctionIR funcIR |
       funcIR.getFunction() = func
@@ -40,7 +21,7 @@ cached private module Cached {
   }
 
   cached OldInstruction getOldInstruction(Instruction instr) {
-    instr.getTag() = WrappedInstructionTag(result)
+    instr = WrappedInstruction(result)
   }
 
   private Instruction getNewInstruction(OldInstruction instr) {
@@ -52,24 +33,12 @@ cached private module Cached {
    * corresponding to `instr` if there is no `Chi` node.
    */
   private Instruction getNewFinalInstruction(OldInstruction instr) {
-    result = getChiInstruction(instr)
+    result = Chi(instr)
     or
-    not exists(getChiInstruction(instr)) and
+    not exists(Chi(instr)) and
     result = getNewInstruction(instr)
   }
 
-  private PhiInstruction getPhiInstruction(Function func, OldBlock oldBlock,
-    Alias::VirtualVariable vvar) {
-    result.getFunction() = func and
-    result.getAST() = oldBlock.getFirstInstruction().getAST() and
-    result.getTag() = PhiTag(vvar, oldBlock)
-  }
-  
-  private ChiInstruction getChiInstruction (OldInstruction instr) {
-    hasChiNode(_, instr) and
-    result.getTag() = ChiTag(instr)
-  }
-
   private IRVariable getNewIRVariable(OldIR::IRVariable var) {
     result.getFunction() = var.getFunction() and
     (
@@ -88,54 +57,23 @@ cached private module Cached {
   }
 
   cached newtype TInstruction =
-    MkInstruction(FunctionIR funcIR, Opcode opcode, Locatable ast,
-        InstructionTag tag, Type resultType, boolean isGLValue) {
-      hasInstruction(funcIR.getFunction(), opcode, ast, tag,
-        resultType, isGLValue)
+    WrappedInstruction(OldInstruction oldInstruction) {
+      not oldInstruction instanceof OldIR::PhiInstruction
+    } or
+    Phi(OldBlock block, Alias::VirtualVariable vvar) {
+      hasPhiNode(vvar, block)
+    } or
+    Chi(OldInstruction oldInstruction) {
+      not oldInstruction instanceof OldIR::PhiInstruction and
+      hasChiNode(_, oldInstruction)
+    } or
+    Unreached(Function function) {
+      exists(OldInstruction oldInstruction |
+        function = oldInstruction.getFunction() and
+        Reachability::isInfeasibleInstructionSuccessor(oldInstruction, _)
+      )
     }
 
-  private predicate hasInstruction(Function func, Opcode opcode, Locatable ast,
-      InstructionTag tag, Type resultType, boolean isGLValue) {
-    exists(OldInstruction instr |
-      instr.getFunction() = func and
-      instr.getOpcode() = opcode and
-      instr.getAST() = ast and
-      WrappedInstructionTag(instr) = tag and
-      instr.getResultType() = resultType and
-      if instr.isGLValue() then
-        isGLValue = true
-      else
-        isGLValue = false
-    ) or
-    exists(OldBlock block, Alias::VirtualVariable vvar |
-      hasPhiNode(vvar, block) and
-      block.getFunction() = func and
-      opcode instanceof Opcode::Phi and
-      ast = block.getFirstInstruction().getAST() and
-      tag = PhiTag(vvar, block) and
-      resultType = vvar.getType() and
-      isGLValue = false
-    ) or
-    exists(OldInstruction instr, Alias::VirtualVariable vvar |
-      hasChiNode(vvar, instr) and
-      instr.getFunction() = func and
-      opcode instanceof Opcode::Chi and
-      ast = instr.getAST() and
-      tag = ChiTag(instr) and
-      resultType = vvar.getType() and
-      isGLValue = false
-    ) or
-    exists(OldInstruction oldInstruction |
-      func = oldInstruction.getFunction() and
-      Reachability::isInfeasibleInstructionSuccessor(oldInstruction, _) and
-      tag = UnreachedTag() and
-      opcode instanceof Opcode::Unreached and
-      ast = func and
-      resultType instanceof VoidType and
-      isGLValue = false
-    )
-  }
-
   cached predicate hasTempVariable(Function func, Locatable ast, TempVariableTag tag,
       Type type) {
     exists(OldIR::IRTempVariable var |
@@ -169,7 +107,7 @@ cached private module Cached {
               if defIndex >= 0 then
                 result = getNewFinalInstruction(defBlock.getInstruction(defIndex))
               else
-                result = getPhiInstruction(instruction.getFunction(), defBlock, vvar)
+                result = Phi(defBlock, vvar)
             )
           )
           else (
@@ -189,7 +127,7 @@ cached private module Cached {
       else 
         result = getNewInstruction(oldOperand.getDefinitionInstruction())
     ) or
-    instruction.getTag() = ChiTag(getOldInstruction(result)) and
+    instruction = Chi(getOldInstruction(result)) and
     tag instanceof ChiPartialOperandTag
     or
     exists(FunctionIR f |
@@ -208,21 +146,21 @@ cached private module Cached {
         OldBlock defBlock, int defRank, int defIndex, OldBlock predBlock |
       hasPhiNode(vvar, phiBlock) and
       predBlock = phiBlock.getAFeasiblePredecessor() and
-      instr.getTag() = PhiTag(vvar, phiBlock) and
+      instr = Phi(phiBlock, vvar) and
       newPredecessorBlock = getNewBlock(predBlock) and
       hasDefinitionAtRank(vvar, defBlock, defRank, defIndex) and
       definitionReachesEndOfBlock(vvar, defBlock, defRank, predBlock) and
       if defIndex >= 0 then
         result = getNewFinalInstruction(defBlock.getInstruction(defIndex))
       else
-        result = getPhiInstruction(instr.getFunction(), defBlock, vvar)
+        result = Phi(defBlock, vvar)
     )
   }
 
   cached Instruction getChiInstructionTotalOperand(ChiInstruction chiInstr) {
     exists(Alias::VirtualVariable vvar, OldInstruction oldInstr, OldBlock defBlock,
         int defRank, int defIndex, OldBlock useBlock, int useRank |
-      ChiTag(oldInstr) = chiInstr.getTag() and
+      chiInstr = Chi(oldInstr) and
       vvar = Alias::getResultMemoryAccess(oldInstr).getVirtualVariable() and
       hasDefinitionAtRank(vvar, defBlock, defRank, defIndex) and
       hasUseAtRank(vvar, useBlock, useRank, oldInstr) and
@@ -230,13 +168,13 @@ cached private module Cached {
       if defIndex >= 0 then
         result = getNewFinalInstruction(defBlock.getInstruction(defIndex))
       else
-        result = getPhiInstruction(chiInstr.getFunction(), defBlock, vvar)
+        result = Phi(defBlock, vvar)
     )
   }
 
   cached Instruction getPhiInstructionBlockStart(PhiInstruction instr) {
     exists(OldBlock oldBlock |
-      instr.getTag() = PhiTag(_, oldBlock) and
+      instr = Phi(oldBlock, _) and
       result = getNewInstruction(oldBlock.getFirstInstruction())
     )
   }
@@ -257,15 +195,14 @@ cached private module Cached {
   cached Instruction getInstructionSuccessor(Instruction instruction, EdgeKind kind) {
     if(hasChiNode(_, getOldInstruction(instruction)))
     then
-      result = getChiInstruction(getOldInstruction(instruction)) and
+      result = Chi(getOldInstruction(instruction)) and
       kind instanceof GotoEdge
     else (
       exists(OldInstruction oldInstruction |
         oldInstruction = getOldInstruction(instruction) and
         (
           if Reachability::isInfeasibleInstructionSuccessor(oldInstruction, kind) then (
-            result.getTag() = UnreachedTag() and
-            result.getFunction() = instruction.getFunction()
+            result = Unreached(instruction.getFunction())
           )
           else (
             result = getNewInstruction(oldInstruction.getSuccessor(kind))
@@ -273,7 +210,7 @@ cached private module Cached {
         )
       ) or
       exists(OldInstruction oldInstruction |
-        instruction = getChiInstruction(oldInstruction) and
+        instruction = Chi(oldInstruction) and
         result = getNewInstruction(oldInstruction.getSuccessor(kind))
       )
     )
@@ -291,11 +228,88 @@ cached private module Cached {
       // `oldInstruction`, in which case the back edge should come out of the
       // chi node instead.
       if hasChiNode(_, oldInstruction)
-      then instruction = getChiInstruction(oldInstruction)
+      then instruction = Chi(oldInstruction)
       else instruction = getNewInstruction(oldInstruction)
     )
   }
 
+  cached Locatable getInstructionAST(Instruction instruction) {
+    exists(OldInstruction oldInstruction |
+      instruction = WrappedInstruction(oldInstruction)
+      or
+      instruction = Chi(oldInstruction)
+    |
+      result = oldInstruction.getAST()
+    )
+    or
+    exists(OldBlock block |
+      instruction = Phi(block, _) and
+      result = block.getFirstInstruction().getAST()
+    )
+    or
+    instruction = Unreached(result)
+  }
+
+  cached predicate instructionHasType(Instruction instruction, Type type, boolean isGLValue) {
+    exists(OldInstruction oldInstruction |
+      instruction = WrappedInstruction(oldInstruction) and
+      type = oldInstruction.getResultType() and
+      if oldInstruction.isGLValue()
+      then isGLValue = true
+      else isGLValue = false
+    )
+    or
+    exists(OldInstruction oldInstruction, Alias::VirtualVariable vvar |
+      instruction = Chi(oldInstruction) and
+      hasChiNode(vvar, oldInstruction) and
+      type = vvar.getType() and
+      isGLValue = false
+    )
+    or
+    exists(Alias::VirtualVariable vvar |
+      instruction = Phi(_, vvar) and
+      type = vvar.getType() and
+      isGLValue = false
+    )
+    or
+    instruction = Unreached(_) and
+    type instanceof VoidType and
+    isGLValue = false
+  }
+
+  cached Opcode getInstructionOpcode(Instruction instruction) {
+    exists(OldInstruction oldInstruction |
+      instruction = WrappedInstruction(oldInstruction) and
+      result = oldInstruction.getOpcode()
+    )
+    or
+    instruction instanceof Chi and
+    result instanceof Opcode::Chi
+    or
+    instruction instanceof Phi and
+    result instanceof Opcode::Phi
+    or
+    instruction instanceof Unreached and
+    result instanceof Opcode::Unreached
+  }
+
+  cached FunctionIR getInstructionEnclosingFunctionIR(Instruction instruction) {
+    exists(OldInstruction oldInstruction |
+      instruction = WrappedInstruction(oldInstruction)
+      or
+      instruction = Chi(oldInstruction)
+    |
+      result.getFunction() = oldInstruction.getFunction()
+    )
+    or
+    exists(OldBlock block |
+      instruction = Phi(block, _) and
+      result.getFunction() = block.getFunction()
+    )
+    or
+    instruction = Unreached(result.getFunction())
+  }
+
   cached IRVariable getInstructionVariable(Instruction instruction) {
     result = getNewIRVariable(getOldInstruction(instruction).(OldIR::VariableInstruction).getVariable())
   }
@@ -346,7 +360,7 @@ cached private module Cached {
     )
     or
     exists(OldIR::Instruction oldInstruction |
-      instruction.getTag() = ChiTag(oldInstruction) and
+      instruction = Chi(oldInstruction) and
       result = getNewInstruction(oldInstruction)
     )
   }
@@ -541,11 +555,11 @@ cached private module CachedForDebugging {
       result = "NonSSA: " + oldInstr.getUniqueId()
     ) or
     exists(Alias::VirtualVariable vvar, OldBlock phiBlock |
-      instr.getTag() = PhiTag(vvar, phiBlock) and
+      instr = Phi(phiBlock, vvar) and
       result = "Phi Block(" + phiBlock.getUniqueId() + "): " + vvar.getUniqueId() 
     ) or
     (
-      instr.getTag() = UnreachedTag() and
+      instr = Unreached(_) and
       result = "Unreached"
     )
   }

cpp/ql/src/semmle/code/cpp/ir/implementation/raw/Instruction.qll

@@ -10,8 +10,6 @@ import semmle.code.cpp.ir.implementation.Opcode
 private import semmle.code.cpp.ir.implementation.Opcode
 private import semmle.code.cpp.ir.internal.OperandTag
 
-class InstructionTag = Construction::InstructionTagType;
-
 module InstructionSanity {
   /**
    * Holds if the instruction `instr` should be expected to have an operand
@@ -211,17 +209,6 @@ module InstructionSanity {
  * Represents a single operation in the IR.
  */
 class Instruction extends Construction::TInstruction {
-  Opcode opcode;
-  Locatable ast;
-  InstructionTag instructionTag;
-  Type resultType;
-  FunctionIR funcIR;
-  boolean glvalue;
-
-  Instruction() {
-    this = Construction::MkInstruction(funcIR, opcode, ast, instructionTag, resultType, glvalue)
-  }
-
   final string toString() {
     result = getOpcode().toString() + ": " + getAST().toString()
   }
@@ -244,9 +231,9 @@ class Instruction extends Construction::TInstruction {
    */
   final string getOperationString() {
     if exists(getImmediateString()) then
-      result = getOperationPrefix() + opcode.toString() + "[" + getImmediateString() + "]"
+      result = getOperationPrefix() + getOpcode().toString() + "[" + getImmediateString() + "]"
     else
-      result = getOperationPrefix() + opcode.toString()
+      result = getOperationPrefix() + getOpcode().toString()
   }
 
   /**
@@ -264,7 +251,7 @@ class Instruction extends Construction::TInstruction {
   }
 
   private string getResultPrefix() {
-    if resultType instanceof VoidType then
+    if getResultType() instanceof VoidType then
       result = "v"
     else if hasMemoryResult() then
       if isResultModeled() then
@@ -309,8 +296,8 @@ class Instruction extends Construction::TInstruction {
 
   private string getResultTypeString() {
     exists(string valcat |
-      valcat = getValueCategoryString(resultType.toString()) and
-      if (resultType instanceof UnknownType and
+      valcat = getValueCategoryString(getResultType().toString()) and
+      if (getResultType() instanceof UnknownType and
           not isGLValue() and
           exists(getResultSize())) then (
         result = valcat + "[" + getResultSize().toString() + "]"
@@ -378,28 +365,28 @@ class Instruction extends Construction::TInstruction {
    * Gets the function that contains this instruction.
    */
   final Function getFunction() {
-    result = funcIR.getFunction()
+    result = getFunctionIR().getFunction()
   }
 
   /**
    * Gets the FunctionIR object that contains the IR for this instruction.
    */
   final FunctionIR getFunctionIR() {
-    result = funcIR
+    result = Construction::getInstructionEnclosingFunctionIR(this)
   }
 
   /**
    * Gets the AST that caused this instruction to be generated.
    */
   final Locatable getAST() {
-    result = ast
+    result = Construction::getInstructionAST(this)
   }
 
   /**
    * Gets the location of the source code for this instruction.
    */
   final Location getLocation() {
-    result = ast.getLocation()
+    result = getAST().getLocation()
   }
 
   /**
@@ -421,7 +408,7 @@ class Instruction extends Construction::TInstruction {
    * instruction does not produce a result, its result type will be `VoidType`.
    */
   final Type getResultType() {
-    result = resultType
+    Construction::instructionHasType(this, result, _)
   }
 
   /**
@@ -443,7 +430,7 @@ class Instruction extends Construction::TInstruction {
    * the integer value loaded from variable `x`.
    */
   final predicate isGLValue() {
-    glvalue = true
+    Construction::instructionHasType(this, _, true)
   }
 
   /**
@@ -460,10 +447,10 @@ class Instruction extends Construction::TInstruction {
         result = nullptr.getSize()
       )
     )
-    else if resultType instanceof UnknownType then
+    else if getResultType() instanceof UnknownType then
       result = Construction::getInstructionResultSize(this)
     else (
-      result = resultType.getSize()
+      result = getResultType().getSize()
     )
   }
 
@@ -471,11 +458,7 @@ class Instruction extends Construction::TInstruction {
    * Gets the opcode that specifies the operation performed by this instruction.
    */
   final Opcode getOpcode() {
-    result = opcode
-  }
-
-  final InstructionTag getTag() {
-    result = instructionTag
+    result = Construction::getInstructionOpcode(this)
   }
 
   /**
@@ -644,19 +627,19 @@ class ConstantValueInstruction extends Instruction {
 
 class EnterFunctionInstruction extends Instruction {
   EnterFunctionInstruction() {
-    opcode instanceof Opcode::EnterFunction
+    getOpcode() instanceof Opcode::EnterFunction
   }
 }
 
 class VariableAddressInstruction extends VariableInstruction {
   VariableAddressInstruction() {
-    opcode instanceof Opcode::VariableAddress
+    getOpcode() instanceof Opcode::VariableAddress
   }
 }
 
 class InitializeParameterInstruction extends VariableInstruction {
   InitializeParameterInstruction() {
-    opcode instanceof Opcode::InitializeParameter
+    getOpcode() instanceof Opcode::InitializeParameter
   }
 
   final Parameter getParameter() {
@@ -673,13 +656,13 @@ class InitializeParameterInstruction extends VariableInstruction {
  */
 class InitializeThisInstruction extends Instruction {
   InitializeThisInstruction() {
-    opcode instanceof Opcode::InitializeThis
+    getOpcode() instanceof Opcode::InitializeThis
   }
 }
 
 class FieldAddressInstruction extends FieldInstruction {
   FieldAddressInstruction() {
-    opcode instanceof Opcode::FieldAddress
+    getOpcode() instanceof Opcode::FieldAddress
   }
 
   final Instruction getObjectAddress() {
@@ -689,7 +672,7 @@ class FieldAddressInstruction extends FieldInstruction {
 
 class UninitializedInstruction extends VariableInstruction {
   UninitializedInstruction() {
-    opcode instanceof Opcode::Uninitialized
+    getOpcode() instanceof Opcode::Uninitialized
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -706,25 +689,25 @@ class UninitializedInstruction extends VariableInstruction {
 
 class NoOpInstruction extends Instruction {
   NoOpInstruction() {
-    opcode instanceof Opcode::NoOp
+    getOpcode() instanceof Opcode::NoOp
   }
 }
 
 class ReturnInstruction extends Instruction {
   ReturnInstruction() {
-    opcode instanceof ReturnOpcode
+    getOpcode() instanceof ReturnOpcode
   }
 }
 
 class ReturnVoidInstruction extends ReturnInstruction {
   ReturnVoidInstruction() {
-    opcode instanceof Opcode::ReturnVoid
+    getOpcode() instanceof Opcode::ReturnVoid
   }
 }
 
 class ReturnValueInstruction extends ReturnInstruction {
   ReturnValueInstruction() {
-    opcode instanceof Opcode::ReturnValue
+    getOpcode() instanceof Opcode::ReturnValue
   }
 
   final Instruction getReturnValue() {
@@ -734,7 +717,7 @@ class ReturnValueInstruction extends ReturnInstruction {
 
 class CopyInstruction extends Instruction {
   CopyInstruction() {
-    opcode instanceof CopyOpcode
+    getOpcode() instanceof CopyOpcode
   }
 
   final Instruction getSourceValue() {
@@ -744,13 +727,13 @@ class CopyInstruction extends Instruction {
 
 class CopyValueInstruction extends CopyInstruction {
   CopyValueInstruction() {
-    opcode instanceof Opcode::CopyValue
+    getOpcode() instanceof Opcode::CopyValue
   }
 }
 
 class LoadInstruction extends CopyInstruction {
   LoadInstruction() {
-    opcode instanceof Opcode::Load
+    getOpcode() instanceof Opcode::Load
   }
 
   final Instruction getSourceAddress() {
@@ -760,7 +743,7 @@ class LoadInstruction extends CopyInstruction {
 
 class StoreInstruction extends CopyInstruction {
   StoreInstruction() {
-    opcode instanceof Opcode::Store
+    getOpcode() instanceof Opcode::Store
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -774,7 +757,7 @@ class StoreInstruction extends CopyInstruction {
 
 class ConditionalBranchInstruction extends Instruction {
   ConditionalBranchInstruction() {
-    opcode instanceof Opcode::ConditionalBranch
+    getOpcode() instanceof Opcode::ConditionalBranch
   }
 
   final Instruction getCondition() {
@@ -792,25 +775,25 @@ class ConditionalBranchInstruction extends Instruction {
 
 class ExitFunctionInstruction extends Instruction {
   ExitFunctionInstruction() {
-    opcode instanceof Opcode::ExitFunction
+    getOpcode() instanceof Opcode::ExitFunction
   }
 }
 
 class ConstantInstruction extends ConstantValueInstruction {
   ConstantInstruction() {
-    opcode instanceof Opcode::Constant
+    getOpcode() instanceof Opcode::Constant
   }
 }
 
 class IntegerConstantInstruction extends ConstantInstruction {
   IntegerConstantInstruction() {
-    resultType instanceof IntegralType
+    getResultType() instanceof IntegralType
   }
 }
 
 class FloatConstantInstruction extends ConstantInstruction {
   FloatConstantInstruction() {
-    resultType instanceof FloatingPointType
+    getResultType() instanceof FloatingPointType
   }
 }
 
@@ -832,7 +815,7 @@ class StringConstantInstruction extends Instruction {
 
 class BinaryInstruction extends Instruction {
   BinaryInstruction() {
-    opcode instanceof BinaryOpcode
+    getOpcode() instanceof BinaryOpcode
   }
 
   final Instruction getLeftOperand() {
@@ -855,67 +838,67 @@ class BinaryInstruction extends Instruction {
 
 class AddInstruction extends BinaryInstruction {
   AddInstruction() {
-    opcode instanceof Opcode::Add
+    getOpcode() instanceof Opcode::Add
   }
 }
 
 class SubInstruction extends BinaryInstruction {
   SubInstruction() {
-    opcode instanceof Opcode::Sub
+    getOpcode() instanceof Opcode::Sub
   }
 }
 
 class MulInstruction extends BinaryInstruction {
   MulInstruction() {
-    opcode instanceof Opcode::Mul
+    getOpcode() instanceof Opcode::Mul
   }
 }
 
 class DivInstruction extends BinaryInstruction {
   DivInstruction() {
-    opcode instanceof Opcode::Div
+    getOpcode() instanceof Opcode::Div
   }
 }
 
 class RemInstruction extends BinaryInstruction {
   RemInstruction() {
-    opcode instanceof Opcode::Rem
+    getOpcode() instanceof Opcode::Rem
   }
 }
 
 class NegateInstruction extends UnaryInstruction {
   NegateInstruction() {
-    opcode instanceof Opcode::Negate
+    getOpcode() instanceof Opcode::Negate
   }
 }
 
 class BitAndInstruction extends BinaryInstruction {
   BitAndInstruction() {
-    opcode instanceof Opcode::BitAnd
+    getOpcode() instanceof Opcode::BitAnd
   }
 }
 
 class BitOrInstruction extends BinaryInstruction {
   BitOrInstruction() {
-    opcode instanceof Opcode::BitOr
+    getOpcode() instanceof Opcode::BitOr
   }
 }
 
 class BitXorInstruction extends BinaryInstruction {
   BitXorInstruction() {
-    opcode instanceof Opcode::BitXor
+    getOpcode() instanceof Opcode::BitXor
   }
 }
 
 class ShiftLeftInstruction extends BinaryInstruction {
   ShiftLeftInstruction() {
-    opcode instanceof Opcode::ShiftLeft
+    getOpcode() instanceof Opcode::ShiftLeft
   }
 }
 
 class ShiftRightInstruction extends BinaryInstruction {
   ShiftRightInstruction() {
-    opcode instanceof Opcode::ShiftRight
+    getOpcode() instanceof Opcode::ShiftRight
   }
 }
 
@@ -923,7 +906,7 @@ class PointerArithmeticInstruction extends BinaryInstruction {
   int elementSize;
 
   PointerArithmeticInstruction() {
-    opcode instanceof PointerArithmeticOpcode and
+    getOpcode() instanceof PointerArithmeticOpcode and
     elementSize = Construction::getInstructionElementSize(this)
   }
 
@@ -938,31 +921,31 @@ class PointerArithmeticInstruction extends BinaryInstruction {
 
 class PointerOffsetInstruction extends PointerArithmeticInstruction {
   PointerOffsetInstruction() {
-    opcode instanceof PointerOffsetOpcode
+    getOpcode() instanceof PointerOffsetOpcode
   }
 }
 
 class PointerAddInstruction extends PointerOffsetInstruction {
   PointerAddInstruction() {
-    opcode instanceof Opcode::PointerAdd
+    getOpcode() instanceof Opcode::PointerAdd
   }
 }
 
 class PointerSubInstruction extends PointerOffsetInstruction {
   PointerSubInstruction() {
-    opcode instanceof Opcode::PointerSub
+    getOpcode() instanceof Opcode::PointerSub
   }
 }
 
 class PointerDiffInstruction extends PointerArithmeticInstruction {
   PointerDiffInstruction() {
-    opcode instanceof Opcode::PointerDiff
+    getOpcode() instanceof Opcode::PointerDiff
   }
 }
 
 class UnaryInstruction extends Instruction {
   UnaryInstruction() {
-    opcode instanceof UnaryOpcode
+    getOpcode() instanceof UnaryOpcode
   }
 
   final Instruction getOperand() {
@@ -972,7 +955,7 @@ class UnaryInstruction extends Instruction {
 
 class ConvertInstruction extends UnaryInstruction {
   ConvertInstruction() {
-    opcode instanceof Opcode::Convert
+    getOpcode() instanceof Opcode::Convert
   }
 }
 
@@ -1024,7 +1007,7 @@ class InheritanceConversionInstruction extends UnaryInstruction {
  */
 class ConvertToBaseInstruction extends InheritanceConversionInstruction {
   ConvertToBaseInstruction() {
-    opcode instanceof Opcode::ConvertToBase
+    getOpcode() instanceof Opcode::ConvertToBase
   }
 }
 
@@ -1034,7 +1017,7 @@ class ConvertToBaseInstruction extends InheritanceConversionInstruction {
  */
 class ConvertToVirtualBaseInstruction extends InheritanceConversionInstruction {
   ConvertToVirtualBaseInstruction() {
-    opcode instanceof Opcode::ConvertToVirtualBase
+    getOpcode() instanceof Opcode::ConvertToVirtualBase
   }
 }
 
@@ -1044,37 +1027,37 @@ class ConvertToVirtualBaseInstruction extends InheritanceConversionInstruction {
  */
 class ConvertToDerivedInstruction extends InheritanceConversionInstruction {
   ConvertToDerivedInstruction() {
-    opcode instanceof Opcode::ConvertToDerived
+    getOpcode() instanceof Opcode::ConvertToDerived
   }
 }
 
 class BitComplementInstruction extends UnaryInstruction {
   BitComplementInstruction() {
-    opcode instanceof Opcode::BitComplement
+    getOpcode() instanceof Opcode::BitComplement
   }
 }
 
 class LogicalNotInstruction extends UnaryInstruction {
   LogicalNotInstruction() {
-    opcode instanceof Opcode::LogicalNot
+    getOpcode() instanceof Opcode::LogicalNot
   }
 }
 
 class CompareInstruction extends BinaryInstruction {
   CompareInstruction() {
-    opcode instanceof CompareOpcode
+    getOpcode() instanceof CompareOpcode
   }
 }
 
 class CompareEQInstruction extends CompareInstruction {
   CompareEQInstruction() {
-    opcode instanceof Opcode::CompareEQ
+    getOpcode() instanceof Opcode::CompareEQ
   }
 }
 
 class CompareNEInstruction extends CompareInstruction {
   CompareNEInstruction() {
-    opcode instanceof Opcode::CompareNE
+    getOpcode() instanceof Opcode::CompareNE
   }
 }
 
@@ -1083,7 +1066,7 @@ class CompareNEInstruction extends CompareInstruction {
  */
 class RelationalInstruction extends CompareInstruction {
   RelationalInstruction() {
-    opcode instanceof RelationalOpcode
+    getOpcode() instanceof RelationalOpcode
   }
 
   /**
@@ -1116,7 +1099,7 @@ class RelationalInstruction extends CompareInstruction {
 
 class CompareLTInstruction extends RelationalInstruction {
   CompareLTInstruction() {
-    opcode instanceof Opcode::CompareLT
+    getOpcode() instanceof Opcode::CompareLT
   }
 
   override Instruction getLesserOperand() {
@@ -1134,7 +1117,7 @@ class CompareLTInstruction extends RelationalInstruction {
 
 class CompareGTInstruction extends RelationalInstruction {
   CompareGTInstruction() {
-    opcode instanceof Opcode::CompareGT
+    getOpcode() instanceof Opcode::CompareGT
   }
 
   override Instruction getLesserOperand() {
@@ -1152,7 +1135,7 @@ class CompareGTInstruction extends RelationalInstruction {
 
 class CompareLEInstruction extends RelationalInstruction {
   CompareLEInstruction() {
-    opcode instanceof Opcode::CompareLE
+    getOpcode() instanceof Opcode::CompareLE
   }
 
   override Instruction getLesserOperand() {
@@ -1170,7 +1153,7 @@ class CompareLEInstruction extends RelationalInstruction {
 
 class CompareGEInstruction extends RelationalInstruction {
   CompareGEInstruction() {
-    opcode instanceof Opcode::CompareGE
+    getOpcode() instanceof Opcode::CompareGE
   }
 
   override Instruction getLesserOperand() {
@@ -1188,7 +1171,7 @@ class CompareGEInstruction extends RelationalInstruction {
 
 class SwitchInstruction extends Instruction {
   SwitchInstruction() {
-    opcode instanceof Opcode::Switch
+    getOpcode() instanceof Opcode::Switch
   }
 
   final Instruction getExpression() {
@@ -1211,7 +1194,7 @@ class SwitchInstruction extends Instruction {
  */
 class CallInstruction extends Instruction {
   CallInstruction() {
-    opcode instanceof Opcode::Call
+    getOpcode() instanceof Opcode::Call
   }
 
   /**
@@ -1254,7 +1237,7 @@ class CallInstruction extends Instruction {
  */
 class SideEffectInstruction extends Instruction {
   SideEffectInstruction() {
-    opcode instanceof SideEffectOpcode
+    getOpcode() instanceof SideEffectOpcode
   }
 
   final Instruction getPrimaryInstruction() {
@@ -1268,7 +1251,7 @@ class SideEffectInstruction extends Instruction {
  */
 class CallSideEffectInstruction extends SideEffectInstruction {
   CallSideEffectInstruction() {
-    opcode instanceof Opcode::CallSideEffect
+    getOpcode() instanceof Opcode::CallSideEffect
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -1282,7 +1265,7 @@ class CallSideEffectInstruction extends SideEffectInstruction {
  */
 class CallReadSideEffectInstruction extends SideEffectInstruction {
   CallReadSideEffectInstruction() {
-    opcode instanceof Opcode::CallReadSideEffect
+    getOpcode() instanceof Opcode::CallReadSideEffect
   }
 }
 
@@ -1291,7 +1274,7 @@ class CallReadSideEffectInstruction extends SideEffectInstruction {
  */
 class IndirectReadSideEffectInstruction extends SideEffectInstruction {
   IndirectReadSideEffectInstruction() {
-    opcode instanceof Opcode::IndirectReadSideEffect
+    getOpcode() instanceof Opcode::IndirectReadSideEffect
   }
 }
 
@@ -1300,7 +1283,7 @@ class IndirectReadSideEffectInstruction extends SideEffectInstruction {
  */
 class BufferReadSideEffectInstruction extends SideEffectInstruction {
   BufferReadSideEffectInstruction() {
-    opcode instanceof Opcode::BufferReadSideEffect
+    getOpcode() instanceof Opcode::BufferReadSideEffect
   }
 }
 
@@ -1309,7 +1292,7 @@ class BufferReadSideEffectInstruction extends SideEffectInstruction {
  */
 class IndirectWriteSideEffectInstruction extends SideEffectInstruction {
   IndirectWriteSideEffectInstruction() {
-    opcode instanceof Opcode::IndirectWriteSideEffect
+    getOpcode() instanceof Opcode::IndirectWriteSideEffect
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -1323,7 +1306,7 @@ class IndirectWriteSideEffectInstruction extends SideEffectInstruction {
  */
 class BufferWriteSideEffectInstruction extends SideEffectInstruction {
   BufferWriteSideEffectInstruction() {
-    opcode instanceof Opcode::BufferWriteSideEffect
+    getOpcode() instanceof Opcode::BufferWriteSideEffect
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -1338,7 +1321,7 @@ class BufferWriteSideEffectInstruction extends SideEffectInstruction {
  */
 class IndirectMayWriteSideEffectInstruction extends SideEffectInstruction {
   IndirectMayWriteSideEffectInstruction() {
-    opcode instanceof Opcode::IndirectMayWriteSideEffect
+    getOpcode() instanceof Opcode::IndirectMayWriteSideEffect
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -1352,7 +1335,7 @@ class IndirectMayWriteSideEffectInstruction extends SideEffectInstruction {
  */
 class BufferMayWriteSideEffectInstruction extends SideEffectInstruction {
   BufferMayWriteSideEffectInstruction() {
-    opcode instanceof Opcode::BufferMayWriteSideEffect
+    getOpcode() instanceof Opcode::BufferMayWriteSideEffect
   }
   override final MemoryAccessKind getResultMemoryAccess() {
     result instanceof BufferMayMemoryAccess
@@ -1364,7 +1347,7 @@ class BufferMayWriteSideEffectInstruction extends SideEffectInstruction {
  */
 class ThrowInstruction extends Instruction {
   ThrowInstruction() {
-    opcode instanceof ThrowOpcode
+    getOpcode() instanceof ThrowOpcode
   }
 }
 
@@ -1373,7 +1356,7 @@ class ThrowInstruction extends Instruction {
  */
 class ThrowValueInstruction extends ThrowInstruction {
   ThrowValueInstruction() {
-    opcode instanceof Opcode::ThrowValue
+    getOpcode() instanceof Opcode::ThrowValue
   }
 
   /**
@@ -1396,7 +1379,7 @@ class ThrowValueInstruction extends ThrowInstruction {
  */
 class ReThrowInstruction extends ThrowInstruction {
   ReThrowInstruction() {
-    opcode instanceof Opcode::ReThrow
+    getOpcode() instanceof Opcode::ReThrow
   }
 }
 
@@ -1405,7 +1388,7 @@ class ReThrowInstruction extends ThrowInstruction {
  */
 class UnwindInstruction extends Instruction {
   UnwindInstruction() {
-    opcode instanceof Opcode::Unwind
+    getOpcode() instanceof Opcode::Unwind
   }
 }
 
@@ -1414,7 +1397,7 @@ class UnwindInstruction extends Instruction {
  */
 class CatchInstruction extends Instruction {
   CatchInstruction() {
-    opcode instanceof CatchOpcode
+    getOpcode() instanceof CatchOpcode
   }
 }
 
@@ -1425,7 +1408,7 @@ class CatchByTypeInstruction extends CatchInstruction {
   Type exceptionType;
 
   CatchByTypeInstruction() {
-    opcode instanceof Opcode::CatchByType and
+    getOpcode() instanceof Opcode::CatchByType and
     exceptionType = Construction::getInstructionExceptionType(this)
   }
 
@@ -1446,13 +1429,13 @@ class CatchByTypeInstruction extends CatchInstruction {
  */
 class CatchAnyInstruction extends CatchInstruction {
   CatchAnyInstruction() {
-    opcode instanceof Opcode::CatchAny
+    getOpcode() instanceof Opcode::CatchAny
   }
 }
 
 class UnmodeledDefinitionInstruction extends Instruction {
   UnmodeledDefinitionInstruction() {
-    opcode instanceof Opcode::UnmodeledDefinition
+    getOpcode() instanceof Opcode::UnmodeledDefinition
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -1465,7 +1448,7 @@ class UnmodeledDefinitionInstruction extends Instruction {
  */
 class AliasedDefinitionInstruction extends Instruction {
   AliasedDefinitionInstruction() {
-    opcode instanceof Opcode::AliasedDefinition
+    getOpcode() instanceof Opcode::AliasedDefinition
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -1475,7 +1458,7 @@ class AliasedDefinitionInstruction extends Instruction {
 
 class UnmodeledUseInstruction extends Instruction {
   UnmodeledUseInstruction() {
-    opcode instanceof Opcode::UnmodeledUse
+    getOpcode() instanceof Opcode::UnmodeledUse
   }
 
   override string getOperandsString() {
@@ -1495,7 +1478,7 @@ class UnmodeledUseInstruction extends Instruction {
  */
 class PhiInstruction extends Instruction {
   PhiInstruction() {
-    opcode instanceof Opcode::Phi
+    getOpcode() instanceof Opcode::Phi
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -1547,7 +1530,7 @@ class PhiInstruction extends Instruction {
  */
 class ChiInstruction extends Instruction {
   ChiInstruction() {
-    opcode instanceof Opcode::Chi
+    getOpcode() instanceof Opcode::Chi
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -1577,7 +1560,7 @@ class ChiInstruction extends Instruction {
  */
 class UnreachedInstruction extends Instruction {
   UnreachedInstruction() {
-    opcode instanceof Opcode::Unreached
+    getOpcode() instanceof Opcode::Unreached
   }
 }
 
@@ -1587,6 +1570,6 @@ class UnreachedInstruction extends Instruction {
  */
 class BuiltInInstruction extends Instruction {
   BuiltInInstruction() {
-    opcode instanceof BuiltInOpcode
+    getOpcode() instanceof BuiltInOpcode
   }
 }

cpp/ql/src/semmle/code/cpp/ir/implementation/raw/internal/IRConstruction.qll

@@ -8,20 +8,12 @@ private import TranslatedExpr
 private import TranslatedStmt
 private import TranslatedFunction
 
-class InstructionTagType extends TInstructionTag {
-  final string toString() {
-    result = "Tag"
-  }
+TranslatedElement getInstructionTranslatedElement(Instruction instruction) {
+  instruction = MkInstruction(result, _)
 }
 
-private TranslatedElement getInstructionTranslatedElement(
-    Instruction instruction) {
-  instruction = result.getInstruction(_)
-}
-
-private TranslatedElement getInstructionTranslatedElementAndTag(
-    Instruction instruction, InstructionTag tag) {
-  instruction = result.getInstruction(tag)
+InstructionTag getInstructionTag(Instruction instruction) {
+  instruction = MkInstruction(_, result)
 }
 
 import Cached
@@ -31,21 +23,10 @@ cached private module Cached {
   }
 
   cached newtype TInstruction =
-    MkInstruction(FunctionIR funcIR, Opcode opcode, Locatable ast,
-        InstructionTag tag, Type resultType, boolean isGLValue) {
-      hasInstruction(funcIR.getFunction(), opcode, ast, tag,
-        resultType, isGLValue)
+    MkInstruction(TranslatedElement element, InstructionTag tag) {
+      element.hasInstruction(_, tag, _, _)
     }
 
-  private predicate hasInstruction(Function func, Opcode opcode, Locatable ast,
-      InstructionTag tag, Type resultType, boolean isGLValue) {
-    exists(TranslatedElement element |
-      element.getAST() = ast and
-      func = element.getFunction() and
-      element.hasInstruction(opcode, tag, resultType, isGLValue)
-    )
-  }
-
   cached predicate hasTempVariable(Function func, Locatable ast, TempVariableTag tag,
     Type type) {
     exists(TranslatedElement element |
@@ -80,7 +61,7 @@ cached private module Cached {
   
   cached Instruction getInstructionOperandDefinition(Instruction instruction, OperandTag tag) {
     result = getInstructionTranslatedElement(instruction).getInstructionOperand(
-      instruction.getTag(), tag)
+      getInstructionTag(instruction), tag)
   }
 
   cached Instruction getPhiInstructionOperandDefinition(Instruction instruction,
@@ -94,7 +75,7 @@ cached private module Cached {
 
   cached Instruction getInstructionSuccessor(Instruction instruction, EdgeKind kind) {
     result = getInstructionTranslatedElement(instruction).getInstructionSuccessor(
-      instruction.getTag(), kind)
+      getInstructionTag(instruction), kind)
   }
 
   // This predicate has pragma[noopt] because otherwise the `getAChild*` calls
@@ -179,9 +160,27 @@ cached private module Cached {
     goto.getLocation().isBefore(goto.getTarget().getLocation())
   }
 
+  cached Locatable getInstructionAST(Instruction instruction) {
+    result = getInstructionTranslatedElement(instruction).getAST()
+  }
+
+  cached predicate instructionHasType(Instruction instruction, Type type, boolean isGLValue) {
+    getInstructionTranslatedElement(instruction)
+      .hasInstruction(_, getInstructionTag(instruction), type, isGLValue)
+  }
+
+  cached Opcode getInstructionOpcode(Instruction instruction) {
+    getInstructionTranslatedElement(instruction)
+      .hasInstruction(result, getInstructionTag(instruction), _, _)
+  }
+
+  cached FunctionIR getInstructionEnclosingFunctionIR(Instruction instruction) {
+    result.getFunction() = getInstructionTranslatedElement(instruction).getFunction()
+  }
+
   cached IRVariable getInstructionVariable(Instruction instruction) {
     result = getInstructionTranslatedElement(instruction).getInstructionVariable(
-      instruction.getTag())
+      getInstructionTag(instruction))
   }
 
   cached Field getInstructionField(Instruction instruction) {
@@ -192,41 +191,39 @@ cached private module Cached {
   }
 
   cached Function getInstructionFunction(Instruction instruction) {
-    exists(InstructionTag tag |
-      result = getInstructionTranslatedElementAndTag(instruction, tag)
-              .getInstructionFunction(tag)
-    )
+    result = getInstructionTranslatedElement(instruction)
+            .getInstructionFunction(getInstructionTag(instruction))
   }
 
   cached string getInstructionConstantValue(Instruction instruction) {
     result =
       getInstructionTranslatedElement(instruction).getInstructionConstantValue(
-        instruction.getTag())
+        getInstructionTag(instruction))
   }
 
   cached StringLiteral getInstructionStringLiteral(Instruction instruction) {
     result =
       getInstructionTranslatedElement(instruction).getInstructionStringLiteral(
-        instruction.getTag())
+        getInstructionTag(instruction))
   }
 
   cached Type getInstructionExceptionType(Instruction instruction) {
     result =
       getInstructionTranslatedElement(instruction).getInstructionExceptionType(
-        instruction.getTag())
+        getInstructionTag(instruction))
   }
 
   cached predicate getInstructionInheritance(Instruction instruction,
       Class baseClass, Class derivedClass) {
     getInstructionTranslatedElement(instruction).getInstructionInheritance(
-      instruction.getTag(), baseClass, derivedClass)
+      getInstructionTag(instruction), baseClass, derivedClass)
   }
 
   pragma[noinline]
   private predicate instructionOrigin(Instruction instruction, 
       TranslatedElement element, InstructionTag tag) {
     element = getInstructionTranslatedElement(instruction) and
-    tag = instruction.getTag()
+    tag = getInstructionTag(instruction)
   }
 
   cached int getInstructionElementSize(Instruction instruction) {
@@ -262,6 +259,6 @@ cached private module CachedForDebugging {
 
   cached string getInstructionUniqueId(Instruction instruction) {
     result = getInstructionTranslatedElement(instruction).getId() + ":" +
-      getInstructionTagId(instruction.getTag())
+      getInstructionTagId(getInstructionTag(instruction))
   }
 }

cpp/ql/src/semmle/code/cpp/ir/implementation/raw/internal/InstructionTag.qll

@@ -86,6 +86,12 @@ newtype TInstructionTag =
     elementIsInitialized(elementIndex)
   }
 
+class InstructionTag extends TInstructionTag {
+  final string toString() {
+    result = "Tag"
+  }
+}
+
 /**
  * Gets a unique string for the instruction tag. Primarily used for generating
  * instruction IDs to ensure stable IR dumps.

cpp/ql/src/semmle/code/cpp/ir/implementation/raw/internal/TranslatedElement.qll

@@ -9,6 +9,7 @@ private import InstructionTag
 private import TranslatedCondition
 private import TranslatedFunction
 private import TranslatedStmt
+private import IRConstruction
 
 /**
  * Gets the built-in `int` type.
@@ -623,18 +624,12 @@ abstract class TranslatedElement extends TTranslatedElement {
     none()
   }
 
-  pragma[noinline]
-  private predicate hasInstructionWithTagAndAst(InstructionTag tag, Locatable ast) {
-    hasInstruction(_, tag, _, _) and
-    ast = getAST()
-  }
-
   /**
    * Gets the instruction generated by this element with tag `tag`.
    */
   final Instruction getInstruction(InstructionTag tag) {
-    hasInstructionWithTagAndAst(tag, result.getAST()) and
-    tag = result.getTag()
+    getInstructionTranslatedElement(result) = this and
+    getInstructionTag(result) = tag
   }
 
   /**

cpp/ql/src/semmle/code/cpp/ir/implementation/unaliased_ssa/Instruction.qll

@@ -10,8 +10,6 @@ import semmle.code.cpp.ir.implementation.Opcode
 private import semmle.code.cpp.ir.implementation.Opcode
 private import semmle.code.cpp.ir.internal.OperandTag
 
-class InstructionTag = Construction::InstructionTagType;
-
 module InstructionSanity {
   /**
    * Holds if the instruction `instr` should be expected to have an operand
@@ -211,17 +209,6 @@ module InstructionSanity {
  * Represents a single operation in the IR.
  */
 class Instruction extends Construction::TInstruction {
-  Opcode opcode;
-  Locatable ast;
-  InstructionTag instructionTag;
-  Type resultType;
-  FunctionIR funcIR;
-  boolean glvalue;
-
-  Instruction() {
-    this = Construction::MkInstruction(funcIR, opcode, ast, instructionTag, resultType, glvalue)
-  }
-
   final string toString() {
     result = getOpcode().toString() + ": " + getAST().toString()
   }
@@ -244,9 +231,9 @@ class Instruction extends Construction::TInstruction {
    */
   final string getOperationString() {
     if exists(getImmediateString()) then
-      result = getOperationPrefix() + opcode.toString() + "[" + getImmediateString() + "]"
+      result = getOperationPrefix() + getOpcode().toString() + "[" + getImmediateString() + "]"
     else
-      result = getOperationPrefix() + opcode.toString()
+      result = getOperationPrefix() + getOpcode().toString()
   }
 
   /**
@@ -264,7 +251,7 @@ class Instruction extends Construction::TInstruction {
   }
 
   private string getResultPrefix() {
-    if resultType instanceof VoidType then
+    if getResultType() instanceof VoidType then
       result = "v"
     else if hasMemoryResult() then
       if isResultModeled() then
@@ -309,8 +296,8 @@ class Instruction extends Construction::TInstruction {
 
   private string getResultTypeString() {
     exists(string valcat |
-      valcat = getValueCategoryString(resultType.toString()) and
-      if (resultType instanceof UnknownType and
+      valcat = getValueCategoryString(getResultType().toString()) and
+      if (getResultType() instanceof UnknownType and
           not isGLValue() and
           exists(getResultSize())) then (
         result = valcat + "[" + getResultSize().toString() + "]"
@@ -378,28 +365,28 @@ class Instruction extends Construction::TInstruction {
    * Gets the function that contains this instruction.
    */
   final Function getFunction() {
-    result = funcIR.getFunction()
+    result = getFunctionIR().getFunction()
   }
 
   /**
    * Gets the FunctionIR object that contains the IR for this instruction.
    */
   final FunctionIR getFunctionIR() {
-    result = funcIR
+    result = Construction::getInstructionEnclosingFunctionIR(this)
   }
 
   /**
    * Gets the AST that caused this instruction to be generated.
    */
   final Locatable getAST() {
-    result = ast
+    result = Construction::getInstructionAST(this)
   }
 
   /**
    * Gets the location of the source code for this instruction.
    */
   final Location getLocation() {
-    result = ast.getLocation()
+    result = getAST().getLocation()
   }
 
   /**
@@ -421,7 +408,7 @@ class Instruction extends Construction::TInstruction {
    * instruction does not produce a result, its result type will be `VoidType`.
    */
   final Type getResultType() {
-    result = resultType
+    Construction::instructionHasType(this, result, _)
   }
 
   /**
@@ -443,7 +430,7 @@ class Instruction extends Construction::TInstruction {
    * the integer value loaded from variable `x`.
    */
   final predicate isGLValue() {
-    glvalue = true
+    Construction::instructionHasType(this, _, true)
   }
 
   /**
@@ -460,10 +447,10 @@ class Instruction extends Construction::TInstruction {
         result = nullptr.getSize()
       )
     )
-    else if resultType instanceof UnknownType then
+    else if getResultType() instanceof UnknownType then
       result = Construction::getInstructionResultSize(this)
     else (
-      result = resultType.getSize()
+      result = getResultType().getSize()
     )
   }
 
@@ -471,11 +458,7 @@ class Instruction extends Construction::TInstruction {
    * Gets the opcode that specifies the operation performed by this instruction.
    */
   final Opcode getOpcode() {
-    result = opcode
-  }
-
-  final InstructionTag getTag() {
-    result = instructionTag
+    result = Construction::getInstructionOpcode(this)
   }
 
   /**
@@ -644,19 +627,19 @@ class ConstantValueInstruction extends Instruction {
 
 class EnterFunctionInstruction extends Instruction {
   EnterFunctionInstruction() {
-    opcode instanceof Opcode::EnterFunction
+    getOpcode() instanceof Opcode::EnterFunction
   }
 }
 
 class VariableAddressInstruction extends VariableInstruction {
   VariableAddressInstruction() {
-    opcode instanceof Opcode::VariableAddress
+    getOpcode() instanceof Opcode::VariableAddress
   }
 }
 
 class InitializeParameterInstruction extends VariableInstruction {
   InitializeParameterInstruction() {
-    opcode instanceof Opcode::InitializeParameter
+    getOpcode() instanceof Opcode::InitializeParameter
   }
 
   final Parameter getParameter() {
@@ -673,13 +656,13 @@ class InitializeParameterInstruction extends VariableInstruction {
  */
 class InitializeThisInstruction extends Instruction {
   InitializeThisInstruction() {
-    opcode instanceof Opcode::InitializeThis
+    getOpcode() instanceof Opcode::InitializeThis
   }
 }
 
 class FieldAddressInstruction extends FieldInstruction {
   FieldAddressInstruction() {
-    opcode instanceof Opcode::FieldAddress
+    getOpcode() instanceof Opcode::FieldAddress
   }
 
   final Instruction getObjectAddress() {
@@ -689,7 +672,7 @@ class FieldAddressInstruction extends FieldInstruction {
 
 class UninitializedInstruction extends VariableInstruction {
   UninitializedInstruction() {
-    opcode instanceof Opcode::Uninitialized
+    getOpcode() instanceof Opcode::Uninitialized
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -706,25 +689,25 @@ class UninitializedInstruction extends VariableInstruction {
 
 class NoOpInstruction extends Instruction {
   NoOpInstruction() {
-    opcode instanceof Opcode::NoOp
+    getOpcode() instanceof Opcode::NoOp
   }
 }
 
 class ReturnInstruction extends Instruction {
   ReturnInstruction() {
-    opcode instanceof ReturnOpcode
+    getOpcode() instanceof ReturnOpcode
   }
 }
 
 class ReturnVoidInstruction extends ReturnInstruction {
   ReturnVoidInstruction() {
-    opcode instanceof Opcode::ReturnVoid
+    getOpcode() instanceof Opcode::ReturnVoid
   }
 }
 
 class ReturnValueInstruction extends ReturnInstruction {
   ReturnValueInstruction() {
-    opcode instanceof Opcode::ReturnValue
+    getOpcode() instanceof Opcode::ReturnValue
   }
 
   final Instruction getReturnValue() {
@@ -734,7 +717,7 @@ class ReturnValueInstruction extends ReturnInstruction {
 
 class CopyInstruction extends Instruction {
   CopyInstruction() {
-    opcode instanceof CopyOpcode
+    getOpcode() instanceof CopyOpcode
   }
 
   final Instruction getSourceValue() {
@@ -744,13 +727,13 @@ class CopyInstruction extends Instruction {
 
 class CopyValueInstruction extends CopyInstruction {
   CopyValueInstruction() {
-    opcode instanceof Opcode::CopyValue
+    getOpcode() instanceof Opcode::CopyValue
   }
 }
 
 class LoadInstruction extends CopyInstruction {
   LoadInstruction() {
-    opcode instanceof Opcode::Load
+    getOpcode() instanceof Opcode::Load
   }
 
   final Instruction getSourceAddress() {
@@ -760,7 +743,7 @@ class LoadInstruction extends CopyInstruction {
 
 class StoreInstruction extends CopyInstruction {
   StoreInstruction() {
-    opcode instanceof Opcode::Store
+    getOpcode() instanceof Opcode::Store
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -774,7 +757,7 @@ class StoreInstruction extends CopyInstruction {
 
 class ConditionalBranchInstruction extends Instruction {
   ConditionalBranchInstruction() {
-    opcode instanceof Opcode::ConditionalBranch
+    getOpcode() instanceof Opcode::ConditionalBranch
   }
 
   final Instruction getCondition() {
@@ -792,25 +775,25 @@ class ConditionalBranchInstruction extends Instruction {
 
 class ExitFunctionInstruction extends Instruction {
   ExitFunctionInstruction() {
-    opcode instanceof Opcode::ExitFunction
+    getOpcode() instanceof Opcode::ExitFunction
   }
 }
 
 class ConstantInstruction extends ConstantValueInstruction {
   ConstantInstruction() {
-    opcode instanceof Opcode::Constant
+    getOpcode() instanceof Opcode::Constant
   }
 }
 
 class IntegerConstantInstruction extends ConstantInstruction {
   IntegerConstantInstruction() {
-    resultType instanceof IntegralType
+    getResultType() instanceof IntegralType
   }
 }
 
 class FloatConstantInstruction extends ConstantInstruction {
   FloatConstantInstruction() {
-    resultType instanceof FloatingPointType
+    getResultType() instanceof FloatingPointType
   }
 }
 
@@ -832,7 +815,7 @@ class StringConstantInstruction extends Instruction {
 
 class BinaryInstruction extends Instruction {
   BinaryInstruction() {
-    opcode instanceof BinaryOpcode
+    getOpcode() instanceof BinaryOpcode
   }
 
   final Instruction getLeftOperand() {
@@ -855,67 +838,67 @@ class BinaryInstruction extends Instruction {
 
 class AddInstruction extends BinaryInstruction {
   AddInstruction() {
-    opcode instanceof Opcode::Add
+    getOpcode() instanceof Opcode::Add
   }
 }
 
 class SubInstruction extends BinaryInstruction {
   SubInstruction() {
-    opcode instanceof Opcode::Sub
+    getOpcode() instanceof Opcode::Sub
   }
 }
 
 class MulInstruction extends BinaryInstruction {
   MulInstruction() {
-    opcode instanceof Opcode::Mul
+    getOpcode() instanceof Opcode::Mul
   }
 }
 
 class DivInstruction extends BinaryInstruction {
   DivInstruction() {
-    opcode instanceof Opcode::Div
+    getOpcode() instanceof Opcode::Div
   }
 }
 
 class RemInstruction extends BinaryInstruction {
   RemInstruction() {
-    opcode instanceof Opcode::Rem
+    getOpcode() instanceof Opcode::Rem
   }
 }
 
 class NegateInstruction extends UnaryInstruction {
   NegateInstruction() {
-    opcode instanceof Opcode::Negate
+    getOpcode() instanceof Opcode::Negate
   }
 }
 
 class BitAndInstruction extends BinaryInstruction {
   BitAndInstruction() {
-    opcode instanceof Opcode::BitAnd
+    getOpcode() instanceof Opcode::BitAnd
   }
 }
 
 class BitOrInstruction extends BinaryInstruction {
   BitOrInstruction() {
-    opcode instanceof Opcode::BitOr
+    getOpcode() instanceof Opcode::BitOr
   }
 }
 
 class BitXorInstruction extends BinaryInstruction {
   BitXorInstruction() {
-    opcode instanceof Opcode::BitXor
+    getOpcode() instanceof Opcode::BitXor
   }
 }
 
 class ShiftLeftInstruction extends BinaryInstruction {
   ShiftLeftInstruction() {
-    opcode instanceof Opcode::ShiftLeft
+    getOpcode() instanceof Opcode::ShiftLeft
   }
 }
 
 class ShiftRightInstruction extends BinaryInstruction {
   ShiftRightInstruction() {
-    opcode instanceof Opcode::ShiftRight
+    getOpcode() instanceof Opcode::ShiftRight
   }
 }
 
@@ -923,7 +906,7 @@ class PointerArithmeticInstruction extends BinaryInstruction {
   int elementSize;
 
   PointerArithmeticInstruction() {
-    opcode instanceof PointerArithmeticOpcode and
+    getOpcode() instanceof PointerArithmeticOpcode and
     elementSize = Construction::getInstructionElementSize(this)
   }
 
@@ -938,31 +921,31 @@ class PointerArithmeticInstruction extends BinaryInstruction {
 
 class PointerOffsetInstruction extends PointerArithmeticInstruction {
   PointerOffsetInstruction() {
-    opcode instanceof PointerOffsetOpcode
+    getOpcode() instanceof PointerOffsetOpcode
   }
 }
 
 class PointerAddInstruction extends PointerOffsetInstruction {
   PointerAddInstruction() {
-    opcode instanceof Opcode::PointerAdd
+    getOpcode() instanceof Opcode::PointerAdd
   }
 }
 
 class PointerSubInstruction extends PointerOffsetInstruction {
   PointerSubInstruction() {
-    opcode instanceof Opcode::PointerSub
+    getOpcode() instanceof Opcode::PointerSub
   }
 }
 
 class PointerDiffInstruction extends PointerArithmeticInstruction {
   PointerDiffInstruction() {
-    opcode instanceof Opcode::PointerDiff
+    getOpcode() instanceof Opcode::PointerDiff
   }
 }
 
 class UnaryInstruction extends Instruction {
   UnaryInstruction() {
-    opcode instanceof UnaryOpcode
+    getOpcode() instanceof UnaryOpcode
   }
 
   final Instruction getOperand() {
@@ -972,7 +955,7 @@ class UnaryInstruction extends Instruction {
 
 class ConvertInstruction extends UnaryInstruction {
   ConvertInstruction() {
-    opcode instanceof Opcode::Convert
+    getOpcode() instanceof Opcode::Convert
   }
 }
 
@@ -1024,7 +1007,7 @@ class InheritanceConversionInstruction extends UnaryInstruction {
  */
 class ConvertToBaseInstruction extends InheritanceConversionInstruction {
   ConvertToBaseInstruction() {
-    opcode instanceof Opcode::ConvertToBase
+    getOpcode() instanceof Opcode::ConvertToBase
   }
 }
 
@@ -1034,7 +1017,7 @@ class ConvertToBaseInstruction extends InheritanceConversionInstruction {
  */
 class ConvertToVirtualBaseInstruction extends InheritanceConversionInstruction {
   ConvertToVirtualBaseInstruction() {
-    opcode instanceof Opcode::ConvertToVirtualBase
+    getOpcode() instanceof Opcode::ConvertToVirtualBase
   }
 }
 
@@ -1044,37 +1027,37 @@ class ConvertToVirtualBaseInstruction extends InheritanceConversionInstruction {
  */
 class ConvertToDerivedInstruction extends InheritanceConversionInstruction {
   ConvertToDerivedInstruction() {
-    opcode instanceof Opcode::ConvertToDerived
+    getOpcode() instanceof Opcode::ConvertToDerived
   }
 }
 
 class BitComplementInstruction extends UnaryInstruction {
   BitComplementInstruction() {
-    opcode instanceof Opcode::BitComplement
+    getOpcode() instanceof Opcode::BitComplement
   }
 }
 
 class LogicalNotInstruction extends UnaryInstruction {
   LogicalNotInstruction() {
-    opcode instanceof Opcode::LogicalNot
+    getOpcode() instanceof Opcode::LogicalNot
   }
 }
 
 class CompareInstruction extends BinaryInstruction {
   CompareInstruction() {
-    opcode instanceof CompareOpcode
+    getOpcode() instanceof CompareOpcode
   }
 }
 
 class CompareEQInstruction extends CompareInstruction {
   CompareEQInstruction() {
-    opcode instanceof Opcode::CompareEQ
+    getOpcode() instanceof Opcode::CompareEQ
   }
 }
 
 class CompareNEInstruction extends CompareInstruction {
   CompareNEInstruction() {
-    opcode instanceof Opcode::CompareNE
+    getOpcode() instanceof Opcode::CompareNE
   }
 }
 
@@ -1083,7 +1066,7 @@ class CompareNEInstruction extends CompareInstruction {
  */
 class RelationalInstruction extends CompareInstruction {
   RelationalInstruction() {
-    opcode instanceof RelationalOpcode
+    getOpcode() instanceof RelationalOpcode
   }
 
   /**
@@ -1116,7 +1099,7 @@ class RelationalInstruction extends CompareInstruction {
 
 class CompareLTInstruction extends RelationalInstruction {
   CompareLTInstruction() {
-    opcode instanceof Opcode::CompareLT
+    getOpcode() instanceof Opcode::CompareLT
   }
 
   override Instruction getLesserOperand() {
@@ -1134,7 +1117,7 @@ class CompareLTInstruction extends RelationalInstruction {
 
 class CompareGTInstruction extends RelationalInstruction {
   CompareGTInstruction() {
-    opcode instanceof Opcode::CompareGT
+    getOpcode() instanceof Opcode::CompareGT
   }
 
   override Instruction getLesserOperand() {
@@ -1152,7 +1135,7 @@ class CompareGTInstruction extends RelationalInstruction {
 
 class CompareLEInstruction extends RelationalInstruction {
   CompareLEInstruction() {
-    opcode instanceof Opcode::CompareLE
+    getOpcode() instanceof Opcode::CompareLE
   }
 
   override Instruction getLesserOperand() {
@@ -1170,7 +1153,7 @@ class CompareLEInstruction extends RelationalInstruction {
 
 class CompareGEInstruction extends RelationalInstruction {
   CompareGEInstruction() {
-    opcode instanceof Opcode::CompareGE
+    getOpcode() instanceof Opcode::CompareGE
   }
 
   override Instruction getLesserOperand() {
@@ -1188,7 +1171,7 @@ class CompareGEInstruction extends RelationalInstruction {
 
 class SwitchInstruction extends Instruction {
   SwitchInstruction() {
-    opcode instanceof Opcode::Switch
+    getOpcode() instanceof Opcode::Switch
   }
 
   final Instruction getExpression() {
@@ -1211,7 +1194,7 @@ class SwitchInstruction extends Instruction {
  */
 class CallInstruction extends Instruction {
   CallInstruction() {
-    opcode instanceof Opcode::Call
+    getOpcode() instanceof Opcode::Call
   }
 
   /**
@@ -1254,7 +1237,7 @@ class CallInstruction extends Instruction {
  */
 class SideEffectInstruction extends Instruction {
   SideEffectInstruction() {
-    opcode instanceof SideEffectOpcode
+    getOpcode() instanceof SideEffectOpcode
   }
 
   final Instruction getPrimaryInstruction() {
@@ -1268,7 +1251,7 @@ class SideEffectInstruction extends Instruction {
  */
 class CallSideEffectInstruction extends SideEffectInstruction {
   CallSideEffectInstruction() {
-    opcode instanceof Opcode::CallSideEffect
+    getOpcode() instanceof Opcode::CallSideEffect
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -1282,7 +1265,7 @@ class CallSideEffectInstruction extends SideEffectInstruction {
  */
 class CallReadSideEffectInstruction extends SideEffectInstruction {
   CallReadSideEffectInstruction() {
-    opcode instanceof Opcode::CallReadSideEffect
+    getOpcode() instanceof Opcode::CallReadSideEffect
   }
 }
 
@@ -1291,7 +1274,7 @@ class CallReadSideEffectInstruction extends SideEffectInstruction {
  */
 class IndirectReadSideEffectInstruction extends SideEffectInstruction {
   IndirectReadSideEffectInstruction() {
-    opcode instanceof Opcode::IndirectReadSideEffect
+    getOpcode() instanceof Opcode::IndirectReadSideEffect
   }
 }
 
@@ -1300,7 +1283,7 @@ class IndirectReadSideEffectInstruction extends SideEffectInstruction {
  */
 class BufferReadSideEffectInstruction extends SideEffectInstruction {
   BufferReadSideEffectInstruction() {
-    opcode instanceof Opcode::BufferReadSideEffect
+    getOpcode() instanceof Opcode::BufferReadSideEffect
   }
 }
 
@@ -1309,7 +1292,7 @@ class BufferReadSideEffectInstruction extends SideEffectInstruction {
  */
 class IndirectWriteSideEffectInstruction extends SideEffectInstruction {
   IndirectWriteSideEffectInstruction() {
-    opcode instanceof Opcode::IndirectWriteSideEffect
+    getOpcode() instanceof Opcode::IndirectWriteSideEffect
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -1323,7 +1306,7 @@ class IndirectWriteSideEffectInstruction extends SideEffectInstruction {
  */
 class BufferWriteSideEffectInstruction extends SideEffectInstruction {
   BufferWriteSideEffectInstruction() {
-    opcode instanceof Opcode::BufferWriteSideEffect
+    getOpcode() instanceof Opcode::BufferWriteSideEffect
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -1338,7 +1321,7 @@ class BufferWriteSideEffectInstruction extends SideEffectInstruction {
  */
 class IndirectMayWriteSideEffectInstruction extends SideEffectInstruction {
   IndirectMayWriteSideEffectInstruction() {
-    opcode instanceof Opcode::IndirectMayWriteSideEffect
+    getOpcode() instanceof Opcode::IndirectMayWriteSideEffect
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -1352,7 +1335,7 @@ class IndirectMayWriteSideEffectInstruction extends SideEffectInstruction {
  */
 class BufferMayWriteSideEffectInstruction extends SideEffectInstruction {
   BufferMayWriteSideEffectInstruction() {
-    opcode instanceof Opcode::BufferMayWriteSideEffect
+    getOpcode() instanceof Opcode::BufferMayWriteSideEffect
   }
   override final MemoryAccessKind getResultMemoryAccess() {
     result instanceof BufferMayMemoryAccess
@@ -1364,7 +1347,7 @@ class BufferMayWriteSideEffectInstruction extends SideEffectInstruction {
  */
 class ThrowInstruction extends Instruction {
   ThrowInstruction() {
-    opcode instanceof ThrowOpcode
+    getOpcode() instanceof ThrowOpcode
   }
 }
 
@@ -1373,7 +1356,7 @@ class ThrowInstruction extends Instruction {
  */
 class ThrowValueInstruction extends ThrowInstruction {
   ThrowValueInstruction() {
-    opcode instanceof Opcode::ThrowValue
+    getOpcode() instanceof Opcode::ThrowValue
   }
 
   /**
@@ -1396,7 +1379,7 @@ class ThrowValueInstruction extends ThrowInstruction {
  */
 class ReThrowInstruction extends ThrowInstruction {
   ReThrowInstruction() {
-    opcode instanceof Opcode::ReThrow
+    getOpcode() instanceof Opcode::ReThrow
   }
 }
 
@@ -1405,7 +1388,7 @@ class ReThrowInstruction extends ThrowInstruction {
  */
 class UnwindInstruction extends Instruction {
   UnwindInstruction() {
-    opcode instanceof Opcode::Unwind
+    getOpcode() instanceof Opcode::Unwind
   }
 }
 
@@ -1414,7 +1397,7 @@ class UnwindInstruction extends Instruction {
  */
 class CatchInstruction extends Instruction {
   CatchInstruction() {
-    opcode instanceof CatchOpcode
+    getOpcode() instanceof CatchOpcode
   }
 }
 
@@ -1425,7 +1408,7 @@ class CatchByTypeInstruction extends CatchInstruction {
   Type exceptionType;
 
   CatchByTypeInstruction() {
-    opcode instanceof Opcode::CatchByType and
+    getOpcode() instanceof Opcode::CatchByType and
     exceptionType = Construction::getInstructionExceptionType(this)
   }
 
@@ -1446,13 +1429,13 @@ class CatchByTypeInstruction extends CatchInstruction {
  */
 class CatchAnyInstruction extends CatchInstruction {
   CatchAnyInstruction() {
-    opcode instanceof Opcode::CatchAny
+    getOpcode() instanceof Opcode::CatchAny
   }
 }
 
 class UnmodeledDefinitionInstruction extends Instruction {
   UnmodeledDefinitionInstruction() {
-    opcode instanceof Opcode::UnmodeledDefinition
+    getOpcode() instanceof Opcode::UnmodeledDefinition
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -1465,7 +1448,7 @@ class UnmodeledDefinitionInstruction extends Instruction {
  */
 class AliasedDefinitionInstruction extends Instruction {
   AliasedDefinitionInstruction() {
-    opcode instanceof Opcode::AliasedDefinition
+    getOpcode() instanceof Opcode::AliasedDefinition
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -1475,7 +1458,7 @@ class AliasedDefinitionInstruction extends Instruction {
 
 class UnmodeledUseInstruction extends Instruction {
   UnmodeledUseInstruction() {
-    opcode instanceof Opcode::UnmodeledUse
+    getOpcode() instanceof Opcode::UnmodeledUse
   }
 
   override string getOperandsString() {
@@ -1495,7 +1478,7 @@ class UnmodeledUseInstruction extends Instruction {
  */
 class PhiInstruction extends Instruction {
   PhiInstruction() {
-    opcode instanceof Opcode::Phi
+    getOpcode() instanceof Opcode::Phi
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -1547,7 +1530,7 @@ class PhiInstruction extends Instruction {
  */
 class ChiInstruction extends Instruction {
   ChiInstruction() {
-    opcode instanceof Opcode::Chi
+    getOpcode() instanceof Opcode::Chi
   }
 
   override final MemoryAccessKind getResultMemoryAccess() {
@@ -1577,7 +1560,7 @@ class ChiInstruction extends Instruction {
  */
 class UnreachedInstruction extends Instruction {
   UnreachedInstruction() {
-    opcode instanceof Opcode::Unreached
+    getOpcode() instanceof Opcode::Unreached
   }
 }
 
@@ -1587,6 +1570,6 @@ class UnreachedInstruction extends Instruction {
  */
 class BuiltInInstruction extends Instruction {
   BuiltInInstruction() {
-    opcode instanceof BuiltInOpcode
+    getOpcode() instanceof BuiltInOpcode
   }
 }

cpp/ql/src/semmle/code/cpp/ir/implementation/unaliased_ssa/internal/SSAConstruction.qll

@@ -14,25 +14,6 @@ cached private module Cached {
     result.getFirstInstruction() = getNewInstruction(oldBlock.getFirstInstruction())
   }
 
-  cached newtype TInstructionTag =
-    WrappedInstructionTag(OldInstruction oldInstruction) {
-      not oldInstruction instanceof OldIR::PhiInstruction
-    } or
-    PhiTag(Alias::VirtualVariable vvar, OldBlock block) {
-      hasPhiNode(vvar, block)
-    } or
-    ChiTag(OldInstruction oldInstruction) {
-      not oldInstruction instanceof OldIR::PhiInstruction and
-      hasChiNode(_, oldInstruction)
-    } or
-    UnreachedTag()
-
-  cached class InstructionTagType extends TInstructionTag {
-    cached final string toString() {
-      result = "Tag"
-    }
-  }
-
   cached predicate functionHasIR(Function func) {
     exists(OldIR::FunctionIR funcIR |
       funcIR.getFunction() = func
@@ -40,7 +21,7 @@ cached private module Cached {
   }
 
   cached OldInstruction getOldInstruction(Instruction instr) {
-    instr.getTag() = WrappedInstructionTag(result)
+    instr = WrappedInstruction(result)
   }
 
   private Instruction getNewInstruction(OldInstruction instr) {
@@ -52,24 +33,12 @@ cached private module Cached {
    * corresponding to `instr` if there is no `Chi` node.
    */
   private Instruction getNewFinalInstruction(OldInstruction instr) {
-    result = getChiInstruction(instr)
+    result = Chi(instr)
     or
-    not exists(getChiInstruction(instr)) and
+    not exists(Chi(instr)) and
     result = getNewInstruction(instr)
   }
 
-  private PhiInstruction getPhiInstruction(Function func, OldBlock oldBlock,
-    Alias::VirtualVariable vvar) {
-    result.getFunction() = func and
-    result.getAST() = oldBlock.getFirstInstruction().getAST() and
-    result.getTag() = PhiTag(vvar, oldBlock)
-  }
-  
-  private ChiInstruction getChiInstruction (OldInstruction instr) {
-    hasChiNode(_, instr) and
-    result.getTag() = ChiTag(instr)
-  }
-
   private IRVariable getNewIRVariable(OldIR::IRVariable var) {
     result.getFunction() = var.getFunction() and
     (
@@ -88,54 +57,23 @@ cached private module Cached {
   }
 
   cached newtype TInstruction =
-    MkInstruction(FunctionIR funcIR, Opcode opcode, Locatable ast,
-        InstructionTag tag, Type resultType, boolean isGLValue) {
-      hasInstruction(funcIR.getFunction(), opcode, ast, tag,
-        resultType, isGLValue)
+    WrappedInstruction(OldInstruction oldInstruction) {
+      not oldInstruction instanceof OldIR::PhiInstruction
+    } or
+    Phi(OldBlock block, Alias::VirtualVariable vvar) {
+      hasPhiNode(vvar, block)
+    } or
+    Chi(OldInstruction oldInstruction) {
+      not oldInstruction instanceof OldIR::PhiInstruction and
+      hasChiNode(_, oldInstruction)
+    } or
+    Unreached(Function function) {
+      exists(OldInstruction oldInstruction |
+        function = oldInstruction.getFunction() and
+        Reachability::isInfeasibleInstructionSuccessor(oldInstruction, _)
+      )
     }
 
-  private predicate hasInstruction(Function func, Opcode opcode, Locatable ast,
-      InstructionTag tag, Type resultType, boolean isGLValue) {
-    exists(OldInstruction instr |
-      instr.getFunction() = func and
-      instr.getOpcode() = opcode and
-      instr.getAST() = ast and
-      WrappedInstructionTag(instr) = tag and
-      instr.getResultType() = resultType and
-      if instr.isGLValue() then
-        isGLValue = true
-      else
-        isGLValue = false
-    ) or
-    exists(OldBlock block, Alias::VirtualVariable vvar |
-      hasPhiNode(vvar, block) and
-      block.getFunction() = func and
-      opcode instanceof Opcode::Phi and
-      ast = block.getFirstInstruction().getAST() and
-      tag = PhiTag(vvar, block) and
-      resultType = vvar.getType() and
-      isGLValue = false
-    ) or
-    exists(OldInstruction instr, Alias::VirtualVariable vvar |
-      hasChiNode(vvar, instr) and
-      instr.getFunction() = func and
-      opcode instanceof Opcode::Chi and
-      ast = instr.getAST() and
-      tag = ChiTag(instr) and
-      resultType = vvar.getType() and
-      isGLValue = false
-    ) or
-    exists(OldInstruction oldInstruction |
-      func = oldInstruction.getFunction() and
-      Reachability::isInfeasibleInstructionSuccessor(oldInstruction, _) and
-      tag = UnreachedTag() and
-      opcode instanceof Opcode::Unreached and
-      ast = func and
-      resultType instanceof VoidType and
-      isGLValue = false
-    )
-  }
-
   cached predicate hasTempVariable(Function func, Locatable ast, TempVariableTag tag,
       Type type) {
     exists(OldIR::IRTempVariable var |
@@ -169,7 +107,7 @@ cached private module Cached {
               if defIndex >= 0 then
                 result = getNewFinalInstruction(defBlock.getInstruction(defIndex))
               else
-                result = getPhiInstruction(instruction.getFunction(), defBlock, vvar)
+                result = Phi(defBlock, vvar)
             )
           )
           else (
@@ -189,7 +127,7 @@ cached private module Cached {
       else 
         result = getNewInstruction(oldOperand.getDefinitionInstruction())
     ) or
-    instruction.getTag() = ChiTag(getOldInstruction(result)) and
+    instruction = Chi(getOldInstruction(result)) and
     tag instanceof ChiPartialOperandTag
     or
     exists(FunctionIR f |
@@ -208,21 +146,21 @@ cached private module Cached {
         OldBlock defBlock, int defRank, int defIndex, OldBlock predBlock |
       hasPhiNode(vvar, phiBlock) and
       predBlock = phiBlock.getAFeasiblePredecessor() and
-      instr.getTag() = PhiTag(vvar, phiBlock) and
+      instr = Phi(phiBlock, vvar) and
       newPredecessorBlock = getNewBlock(predBlock) and
       hasDefinitionAtRank(vvar, defBlock, defRank, defIndex) and
       definitionReachesEndOfBlock(vvar, defBlock, defRank, predBlock) and
       if defIndex >= 0 then
         result = getNewFinalInstruction(defBlock.getInstruction(defIndex))
       else
-        result = getPhiInstruction(instr.getFunction(), defBlock, vvar)
+        result = Phi(defBlock, vvar)
     )
   }
 
   cached Instruction getChiInstructionTotalOperand(ChiInstruction chiInstr) {
     exists(Alias::VirtualVariable vvar, OldInstruction oldInstr, OldBlock defBlock,
         int defRank, int defIndex, OldBlock useBlock, int useRank |
-      ChiTag(oldInstr) = chiInstr.getTag() and
+      chiInstr = Chi(oldInstr) and
       vvar = Alias::getResultMemoryAccess(oldInstr).getVirtualVariable() and
       hasDefinitionAtRank(vvar, defBlock, defRank, defIndex) and
       hasUseAtRank(vvar, useBlock, useRank, oldInstr) and
@@ -230,13 +168,13 @@ cached private module Cached {
       if defIndex >= 0 then
         result = getNewFinalInstruction(defBlock.getInstruction(defIndex))
       else
-        result = getPhiInstruction(chiInstr.getFunction(), defBlock, vvar)
+        result = Phi(defBlock, vvar)
     )
   }
 
   cached Instruction getPhiInstructionBlockStart(PhiInstruction instr) {
     exists(OldBlock oldBlock |
-      instr.getTag() = PhiTag(_, oldBlock) and
+      instr = Phi(oldBlock, _) and
       result = getNewInstruction(oldBlock.getFirstInstruction())
     )
   }
@@ -257,15 +195,14 @@ cached private module Cached {
   cached Instruction getInstructionSuccessor(Instruction instruction, EdgeKind kind) {
     if(hasChiNode(_, getOldInstruction(instruction)))
     then
-      result = getChiInstruction(getOldInstruction(instruction)) and
+      result = Chi(getOldInstruction(instruction)) and
       kind instanceof GotoEdge
     else (
       exists(OldInstruction oldInstruction |
         oldInstruction = getOldInstruction(instruction) and
         (
           if Reachability::isInfeasibleInstructionSuccessor(oldInstruction, kind) then (
-            result.getTag() = UnreachedTag() and
-            result.getFunction() = instruction.getFunction()
+            result = Unreached(instruction.getFunction())
           )
           else (
             result = getNewInstruction(oldInstruction.getSuccessor(kind))
@@ -273,7 +210,7 @@ cached private module Cached {
         )
       ) or
       exists(OldInstruction oldInstruction |
-        instruction = getChiInstruction(oldInstruction) and
+        instruction = Chi(oldInstruction) and
         result = getNewInstruction(oldInstruction.getSuccessor(kind))
       )
     )
@@ -291,11 +228,88 @@ cached private module Cached {
       // `oldInstruction`, in which case the back edge should come out of the
       // chi node instead.
       if hasChiNode(_, oldInstruction)
-      then instruction = getChiInstruction(oldInstruction)
+      then instruction = Chi(oldInstruction)
       else instruction = getNewInstruction(oldInstruction)
     )
   }
 
+  cached Locatable getInstructionAST(Instruction instruction) {
+    exists(OldInstruction oldInstruction |
+      instruction = WrappedInstruction(oldInstruction)
+      or
+      instruction = Chi(oldInstruction)
+    |
+      result = oldInstruction.getAST()
+    )
+    or
+    exists(OldBlock block |
+      instruction = Phi(block, _) and
+      result = block.getFirstInstruction().getAST()
+    )
+    or
+    instruction = Unreached(result)
+  }
+
+  cached predicate instructionHasType(Instruction instruction, Type type, boolean isGLValue) {
+    exists(OldInstruction oldInstruction |
+      instruction = WrappedInstruction(oldInstruction) and
+      type = oldInstruction.getResultType() and
+      if oldInstruction.isGLValue()
+      then isGLValue = true
+      else isGLValue = false
+    )
+    or
+    exists(OldInstruction oldInstruction, Alias::VirtualVariable vvar |
+      instruction = Chi(oldInstruction) and
+      hasChiNode(vvar, oldInstruction) and
+      type = vvar.getType() and
+      isGLValue = false
+    )
+    or
+    exists(Alias::VirtualVariable vvar |
+      instruction = Phi(_, vvar) and
+      type = vvar.getType() and
+      isGLValue = false
+    )
+    or
+    instruction = Unreached(_) and
+    type instanceof VoidType and
+    isGLValue = false
+  }
+
+  cached Opcode getInstructionOpcode(Instruction instruction) {
+    exists(OldInstruction oldInstruction |
+      instruction = WrappedInstruction(oldInstruction) and
+      result = oldInstruction.getOpcode()
+    )
+    or
+    instruction instanceof Chi and
+    result instanceof Opcode::Chi
+    or
+    instruction instanceof Phi and
+    result instanceof Opcode::Phi
+    or
+    instruction instanceof Unreached and
+    result instanceof Opcode::Unreached
+  }
+
+  cached FunctionIR getInstructionEnclosingFunctionIR(Instruction instruction) {
+    exists(OldInstruction oldInstruction |
+      instruction = WrappedInstruction(oldInstruction)
+      or
+      instruction = Chi(oldInstruction)
+    |
+      result.getFunction() = oldInstruction.getFunction()
+    )
+    or
+    exists(OldBlock block |
+      instruction = Phi(block, _) and
+      result.getFunction() = block.getFunction()
+    )
+    or
+    instruction = Unreached(result.getFunction())
+  }
+
   cached IRVariable getInstructionVariable(Instruction instruction) {
     result = getNewIRVariable(getOldInstruction(instruction).(OldIR::VariableInstruction).getVariable())
   }
@@ -346,7 +360,7 @@ cached private module Cached {
     )
     or
     exists(OldIR::Instruction oldInstruction |
-      instruction.getTag() = ChiTag(oldInstruction) and
+      instruction = Chi(oldInstruction) and
       result = getNewInstruction(oldInstruction)
     )
   }
@@ -541,11 +555,11 @@ cached private module CachedForDebugging {
       result = "NonSSA: " + oldInstr.getUniqueId()
     ) or
     exists(Alias::VirtualVariable vvar, OldBlock phiBlock |
-      instr.getTag() = PhiTag(vvar, phiBlock) and
+      instr = Phi(phiBlock, vvar) and
       result = "Phi Block(" + phiBlock.getUniqueId() + "): " + vvar.getUniqueId() 
     ) or
     (
-      instr.getTag() = UnreachedTag() and
+      instr = Unreached(_) and
       result = "Unreached"
     )
   }