C++: PhiOperand -> PhiInputOperand

dave-bartolomeo · dave-bartolomeo · commit b0ad64c3e700 · 2019-03-12T11:57:53.000-07:00
Also added `PhiInstruction::getAnInputOperand()`, and renamed `PhiInstruction::getAnOperandDefinitionInstruction()` to `getAnInput()` for consistency with other `Instruction` classes.
diff --git a/cpp/ql/src/semmle/code/cpp/ir/implementation/aliased_ssa/Instruction.qll b/cpp/ql/src/semmle/code/cpp/ir/implementation/aliased_ssa/Instruction.qll
@@ -15,7 +15,7 @@ module InstructionSanity {
   /**
    * Holds if the instruction `instr` should be expected to have an operand
    * with operand tag `tag`. Only holds for singleton operand tags. Tags with
-   * parameters, such as `PhiOperand` and `PositionalArgumentOperand` are handled
+   * parameters, such as `PhiInputOperand` and `PositionalArgumentOperand` are handled
    * separately in `unexpectedOperand`.
    */
   private predicate expectsOperand(Instruction instr, OperandTag tag) {
@@ -87,7 +87,7 @@ module InstructionSanity {
    */
   query predicate missingPhiOperand(PhiInstruction instr, IRBlock pred) {
     pred = instr.getBlock().getAPredecessor() and
-    not exists(PhiOperand operand |
+    not exists(PhiInputOperand operand |
       operand = instr.getAnOperand() and
       operand.getPredecessorBlock() = pred
     )
@@ -1622,15 +1622,22 @@ class PhiInstruction extends Instruction {
     result instanceof PhiMemoryAccess
   }
 
+  /**
+   * Gets all of the instruction's `PhiInputOperand`s, representing the values that flow from each predecessor block.
+   */
+  final PhiInputOperand getAnInputOperand() {
+    result = this.getAnOperand()
+  }
+
   /**
    * Gets an instruction that defines the input to one of the operands of this
    * instruction. It's possible for more than one operand to have the same
    * defining instruction, so this predicate will have the same number of
-   * results as `getAnOperand()` or fewer.
+   * results as `getAnInputOperand()` or fewer.
    */
   pragma[noinline]
-  final Instruction getAnOperandDefinitionInstruction() {
-    result = this.getAnOperand().(PhiOperand).getDefinitionInstruction()
+  final Instruction getAnInput() {
+    result = this.getAnInputOperand().getDefinitionInstruction()
   }
 }
 
diff --git a/cpp/ql/src/semmle/code/cpp/ir/implementation/aliased_ssa/Operand.qll b/cpp/ql/src/semmle/code/cpp/ir/implementation/aliased_ssa/Operand.qll
@@ -379,12 +379,12 @@ class SideEffectOperand extends TypedOperand {
 /**
  * An operand of a `PhiInstruction`.
  */
-class PhiOperand extends MemoryOperand, TPhiOperand {
+class PhiInputOperand extends MemoryOperand, TPhiOperand {
   PhiInstruction useInstr;
   Instruction defInstr;
   IRBlock predecessorBlock;
 
-  PhiOperand() {
+  PhiInputOperand() {
     this = TPhiOperand(useInstr, defInstr, predecessorBlock)
   }
 
diff --git a/cpp/ql/src/semmle/code/cpp/ir/implementation/aliased_ssa/constant/ConstantAnalysis.qll b/cpp/ql/src/semmle/code/cpp/ir/implementation/aliased_ssa/constant/ConstantAnalysis.qll
@@ -10,16 +10,16 @@ int getConstantValue(Instruction instr) {
   result = getConstantValue(instr.(CopyInstruction).getSourceValue()) or
   exists(PhiInstruction phi |
     phi = instr and
-    result = max(Instruction def | def = phi.getAnOperandDefinitionInstruction() | getConstantValueToPhi(def)) and
-    result = min(Instruction def | def = phi.getAnOperandDefinitionInstruction() | getConstantValueToPhi(def))
+    result = max(Instruction def | def = phi.getAnInput() | getConstantValueToPhi(def)) and
+    result = min(Instruction def | def = phi.getAnInput() | getConstantValueToPhi(def))
   )
 }
 
 pragma[noinline]
 int getConstantValueToPhi(Instruction def) {
   exists(PhiInstruction phi |
     result = getConstantValue(def) and
-    def = phi.getAnOperandDefinitionInstruction()
+    def = phi.getAnInput()
   )
 }
 
diff --git a/cpp/ql/src/semmle/code/cpp/ir/implementation/aliased_ssa/internal/AliasAnalysis.qll b/cpp/ql/src/semmle/code/cpp/ir/implementation/aliased_ssa/internal/AliasAnalysis.qll
@@ -73,7 +73,7 @@ private predicate operandEscapesDomain(Operand operand) {
   not isArgumentForParameter(_, operand, _) and
   not isOnlyEscapesViaReturnArgument(operand) and
   not operand.getUseInstruction() instanceof ReturnValueInstruction and
-  not operand instanceof PhiOperand
+  not operand instanceof PhiInputOperand
 }
 
 /**
@@ -171,7 +171,7 @@ private predicate operandEscapesNonReturn(Operand operand) {
   or
   isOnlyEscapesViaReturnArgument(operand) and resultEscapesNonReturn(operand.getUseInstruction())
   or
-  operand instanceof PhiOperand and
+  operand instanceof PhiInputOperand and
   resultEscapesNonReturn(operand.getUseInstruction())
   or
   operandEscapesDomain(operand)
@@ -194,7 +194,7 @@ private predicate operandMayReachReturn(Operand operand) {
   or
   isOnlyEscapesViaReturnArgument(operand) and resultMayReachReturn(operand.getUseInstruction())
   or
-  operand instanceof PhiOperand and
+  operand instanceof PhiInputOperand and
   resultMayReachReturn(operand.getUseInstruction())
 }
 
diff --git a/cpp/ql/src/semmle/code/cpp/ir/implementation/raw/Instruction.qll b/cpp/ql/src/semmle/code/cpp/ir/implementation/raw/Instruction.qll
@@ -15,7 +15,7 @@ module InstructionSanity {
   /**
    * Holds if the instruction `instr` should be expected to have an operand
    * with operand tag `tag`. Only holds for singleton operand tags. Tags with
-   * parameters, such as `PhiOperand` and `PositionalArgumentOperand` are handled
+   * parameters, such as `PhiInputOperand` and `PositionalArgumentOperand` are handled
    * separately in `unexpectedOperand`.
    */
   private predicate expectsOperand(Instruction instr, OperandTag tag) {
@@ -87,7 +87,7 @@ module InstructionSanity {
    */
   query predicate missingPhiOperand(PhiInstruction instr, IRBlock pred) {
     pred = instr.getBlock().getAPredecessor() and
-    not exists(PhiOperand operand |
+    not exists(PhiInputOperand operand |
       operand = instr.getAnOperand() and
       operand.getPredecessorBlock() = pred
     )
@@ -1622,15 +1622,22 @@ class PhiInstruction extends Instruction {
     result instanceof PhiMemoryAccess
   }
 
+  /**
+   * Gets all of the instruction's `PhiInputOperand`s, representing the values that flow from each predecessor block.
+   */
+  final PhiInputOperand getAnInputOperand() {
+    result = this.getAnOperand()
+  }
+
   /**
    * Gets an instruction that defines the input to one of the operands of this
    * instruction. It's possible for more than one operand to have the same
    * defining instruction, so this predicate will have the same number of
-   * results as `getAnOperand()` or fewer.
+   * results as `getAnInputOperand()` or fewer.
    */
   pragma[noinline]
-  final Instruction getAnOperandDefinitionInstruction() {
-    result = this.getAnOperand().(PhiOperand).getDefinitionInstruction()
+  final Instruction getAnInput() {
+    result = this.getAnInputOperand().getDefinitionInstruction()
   }
 }
 
diff --git a/cpp/ql/src/semmle/code/cpp/ir/implementation/raw/Operand.qll b/cpp/ql/src/semmle/code/cpp/ir/implementation/raw/Operand.qll
@@ -379,12 +379,12 @@ class SideEffectOperand extends TypedOperand {
 /**
  * An operand of a `PhiInstruction`.
  */
-class PhiOperand extends MemoryOperand, TPhiOperand {
+class PhiInputOperand extends MemoryOperand, TPhiOperand {
   PhiInstruction useInstr;
   Instruction defInstr;
   IRBlock predecessorBlock;
 
-  PhiOperand() {
+  PhiInputOperand() {
     this = TPhiOperand(useInstr, defInstr, predecessorBlock)
   }
 
diff --git a/cpp/ql/src/semmle/code/cpp/ir/implementation/raw/constant/ConstantAnalysis.qll b/cpp/ql/src/semmle/code/cpp/ir/implementation/raw/constant/ConstantAnalysis.qll
@@ -10,16 +10,16 @@ int getConstantValue(Instruction instr) {
   result = getConstantValue(instr.(CopyInstruction).getSourceValue()) or
   exists(PhiInstruction phi |
     phi = instr and
-    result = max(Instruction def | def = phi.getAnOperandDefinitionInstruction() | getConstantValueToPhi(def)) and
-    result = min(Instruction def | def = phi.getAnOperandDefinitionInstruction() | getConstantValueToPhi(def))
+    result = max(Instruction def | def = phi.getAnInput() | getConstantValueToPhi(def)) and
+    result = min(Instruction def | def = phi.getAnInput() | getConstantValueToPhi(def))
   )
 }
 
 pragma[noinline]
 int getConstantValueToPhi(Instruction def) {
   exists(PhiInstruction phi |
     result = getConstantValue(def) and
-    def = phi.getAnOperandDefinitionInstruction()
+    def = phi.getAnInput()
   )
 }
 
diff --git a/cpp/ql/src/semmle/code/cpp/ir/implementation/unaliased_ssa/Instruction.qll b/cpp/ql/src/semmle/code/cpp/ir/implementation/unaliased_ssa/Instruction.qll
@@ -15,7 +15,7 @@ module InstructionSanity {
   /**
    * Holds if the instruction `instr` should be expected to have an operand
    * with operand tag `tag`. Only holds for singleton operand tags. Tags with
-   * parameters, such as `PhiOperand` and `PositionalArgumentOperand` are handled
+   * parameters, such as `PhiInputOperand` and `PositionalArgumentOperand` are handled
    * separately in `unexpectedOperand`.
    */
   private predicate expectsOperand(Instruction instr, OperandTag tag) {
@@ -87,7 +87,7 @@ module InstructionSanity {
    */
   query predicate missingPhiOperand(PhiInstruction instr, IRBlock pred) {
     pred = instr.getBlock().getAPredecessor() and
-    not exists(PhiOperand operand |
+    not exists(PhiInputOperand operand |
       operand = instr.getAnOperand() and
       operand.getPredecessorBlock() = pred
     )
@@ -1622,15 +1622,22 @@ class PhiInstruction extends Instruction {
     result instanceof PhiMemoryAccess
   }
 
+  /**
+   * Gets all of the instruction's `PhiInputOperand`s, representing the values that flow from each predecessor block.
+   */
+  final PhiInputOperand getAnInputOperand() {
+    result = this.getAnOperand()
+  }
+
   /**
    * Gets an instruction that defines the input to one of the operands of this
    * instruction. It's possible for more than one operand to have the same
    * defining instruction, so this predicate will have the same number of
-   * results as `getAnOperand()` or fewer.
+   * results as `getAnInputOperand()` or fewer.
    */
   pragma[noinline]
-  final Instruction getAnOperandDefinitionInstruction() {
-    result = this.getAnOperand().(PhiOperand).getDefinitionInstruction()
+  final Instruction getAnInput() {
+    result = this.getAnInputOperand().getDefinitionInstruction()
   }
 }
 
diff --git a/cpp/ql/src/semmle/code/cpp/ir/implementation/unaliased_ssa/Operand.qll b/cpp/ql/src/semmle/code/cpp/ir/implementation/unaliased_ssa/Operand.qll
@@ -379,12 +379,12 @@ class SideEffectOperand extends TypedOperand {
 /**
  * An operand of a `PhiInstruction`.
  */
-class PhiOperand extends MemoryOperand, TPhiOperand {
+class PhiInputOperand extends MemoryOperand, TPhiOperand {
   PhiInstruction useInstr;
   Instruction defInstr;
   IRBlock predecessorBlock;
 
-  PhiOperand() {
+  PhiInputOperand() {
     this = TPhiOperand(useInstr, defInstr, predecessorBlock)
   }
 
diff --git a/cpp/ql/src/semmle/code/cpp/ir/implementation/unaliased_ssa/constant/ConstantAnalysis.qll b/cpp/ql/src/semmle/code/cpp/ir/implementation/unaliased_ssa/constant/ConstantAnalysis.qll
@@ -10,16 +10,16 @@ int getConstantValue(Instruction instr) {
   result = getConstantValue(instr.(CopyInstruction).getSourceValue()) or
   exists(PhiInstruction phi |
     phi = instr and
-    result = max(Instruction def | def = phi.getAnOperandDefinitionInstruction() | getConstantValueToPhi(def)) and
-    result = min(Instruction def | def = phi.getAnOperandDefinitionInstruction() | getConstantValueToPhi(def))
+    result = max(Instruction def | def = phi.getAnInput() | getConstantValueToPhi(def)) and
+    result = min(Instruction def | def = phi.getAnInput() | getConstantValueToPhi(def))
   )
 }
 
 pragma[noinline]
 int getConstantValueToPhi(Instruction def) {
   exists(PhiInstruction phi |
     result = getConstantValue(def) and
-    def = phi.getAnOperandDefinitionInstruction()
+    def = phi.getAnInput()
   )
 }
 
diff --git a/cpp/ql/src/semmle/code/cpp/ir/implementation/unaliased_ssa/internal/AliasAnalysis.qll b/cpp/ql/src/semmle/code/cpp/ir/implementation/unaliased_ssa/internal/AliasAnalysis.qll
@@ -73,7 +73,7 @@ private predicate operandEscapesDomain(Operand operand) {
   not isArgumentForParameter(_, operand, _) and
   not isOnlyEscapesViaReturnArgument(operand) and
   not operand.getUseInstruction() instanceof ReturnValueInstruction and
-  not operand instanceof PhiOperand
+  not operand instanceof PhiInputOperand
 }
 
 /**
@@ -171,7 +171,7 @@ private predicate operandEscapesNonReturn(Operand operand) {
   or
   isOnlyEscapesViaReturnArgument(operand) and resultEscapesNonReturn(operand.getUseInstruction())
   or
-  operand instanceof PhiOperand and
+  operand instanceof PhiInputOperand and
   resultEscapesNonReturn(operand.getUseInstruction())
   or
   operandEscapesDomain(operand)
@@ -194,7 +194,7 @@ private predicate operandMayReachReturn(Operand operand) {
   or
   isOnlyEscapesViaReturnArgument(operand) and resultMayReachReturn(operand.getUseInstruction())
   or
-  operand instanceof PhiOperand and
+  operand instanceof PhiInputOperand and
   resultMayReachReturn(operand.getUseInstruction())
 }
 
diff --git a/cpp/ql/src/semmle/code/cpp/rangeanalysis/RangeAnalysis.qll b/cpp/ql/src/semmle/code/cpp/rangeanalysis/RangeAnalysis.qll
@@ -377,7 +377,7 @@ private predicate boundedNonPhiOperand(NonPhiOperand op, Bound b, int delta, boo
  * - `upper = false` : `op2 >= op1 + delta`
  */
 private predicate boundFlowStepPhi(
-  PhiOperand op2, Operand op1, int delta, boolean upper, Reason reason
+  PhiInputOperand op2, Operand op1, int delta, boolean upper, Reason reason
 ) {
   op2.getDefinitionInstruction().(CopyInstruction).getSourceValueOperand() = op1 and
   (upper = true or upper = false) and
@@ -393,7 +393,7 @@ private predicate boundFlowStepPhi(
 
 
 private predicate boundedPhiOperand(
-  PhiOperand op, Bound b, int delta, boolean upper, boolean fromBackEdge, int origdelta,
+  PhiInputOperand op, Bound b, int delta, boolean upper, boolean fromBackEdge, int origdelta,
   Reason reason
 ) {
   exists(NonPhiOperand op2, int d1, int d2, Reason r1, Reason r2 |
@@ -446,7 +446,7 @@ private predicate unequalOperand(Operand op, Bound b, int delta, Reason reason)
 
 private predicate boundedPhiCandValidForEdge(
   PhiInstruction phi, Bound b, int delta, boolean upper, boolean fromBackEdge, int origdelta,
-  Reason reason, PhiOperand op
+  Reason reason, PhiInputOperand op
 ) {
   boundedPhiCand(phi, upper, b, delta, fromBackEdge, origdelta, reason) and
   (
@@ -469,7 +469,7 @@ private int weakenDelta(boolean upper, int delta) {
 }
 
 private predicate boundedPhiInp(
-  PhiInstruction phi, PhiOperand op, Bound b, int delta, boolean upper, boolean fromBackEdge,
+  PhiInstruction phi, PhiInputOperand op, Bound b, int delta, boolean upper, boolean fromBackEdge,
   int origdelta, Reason reason
 ) {
   phi.getAnOperand() = op and
@@ -499,12 +499,12 @@ private predicate boundedPhiInp(
 
 pragma[noinline]
 private predicate boundedPhiInp1(
-  PhiInstruction phi, PhiOperand op, Bound b, int delta, boolean upper
+  PhiInstruction phi, PhiInputOperand op, Bound b, int delta, boolean upper
 ) {
   boundedPhiInp(phi, op, b, delta, upper, _, _, _)
 }
 
-private predicate selfBoundedPhiInp(PhiInstruction phi, PhiOperand op, boolean upper) {
+private predicate selfBoundedPhiInp(PhiInstruction phi, PhiInputOperand op, boolean upper) {
   exists(int d, ValueNumberBound phibound |
     phibound.getInstruction() = phi and
     boundedPhiInp(phi, op, phibound, d, upper, _, _, _) and
@@ -521,7 +521,7 @@ private predicate boundedPhiCand(
   PhiInstruction phi, boolean upper, Bound b, int delta, boolean fromBackEdge, int origdelta,
   Reason reason
 ) {
-  exists(PhiOperand op |
+  exists(PhiInputOperand op |
     boundedPhiInp(phi, op, b, delta, upper, fromBackEdge, origdelta, reason)
   )
 }
@@ -556,7 +556,7 @@ private predicate boundedInstruction(
   Instruction i, Bound b, int delta, boolean upper, boolean fromBackEdge, int origdelta, Reason reason
 ) {
   i instanceof PhiInstruction and
-  forex(PhiOperand op | op = i.getAnOperand() |
+  forex(PhiInputOperand op | op = i.getAnOperand() |
     boundedPhiCandValidForEdge(i, b, delta, upper, fromBackEdge, origdelta, reason, op)
   )
   or
diff --git a/cpp/ql/src/semmle/code/cpp/rangeanalysis/RangeUtils.qll b/cpp/ql/src/semmle/code/cpp/rangeanalysis/RangeUtils.qll
@@ -22,8 +22,8 @@ IntValue getConstantValue(Instruction instr) {
   result = getConstantValue(instr.(CopyInstruction).getSourceValue()) or
   exists(PhiInstruction phi |
     phi = instr and
-    result = max(PhiOperand operand | operand = phi.getAnOperand() | getConstantValue(operand.getDefinitionInstruction())) and
-    result = min(PhiOperand operand | operand = phi.getAnOperand() | getConstantValue(operand.getDefinitionInstruction()))
+    result = max(PhiInputOperand operand | operand = phi.getAnOperand() | getConstantValue(operand.getDefinitionInstruction())) and
+    result = min(PhiInputOperand operand | operand = phi.getAnOperand() | getConstantValue(operand.getDefinitionInstruction()))
   )
 }
 
@@ -63,7 +63,7 @@ predicate valueFlowStep(Instruction i, Operand op, int delta) {
   )
 }
 
-predicate backEdge(PhiInstruction phi, PhiOperand op) {
+predicate backEdge(PhiInstruction phi, PhiInputOperand op) {
   phi.getAnOperand() = op and
   phi.getBlock() = op.getPredecessorBlock().getBackEdgeSuccessor(_)
 }

Original file line number	Diff line number	Diff line change
`@@ -10,16 +10,16 @@ int getConstantValue(Instruction instr) {`
`10`	`10`	`result = getConstantValue(instr.(CopyInstruction).getSourceValue()) or`
`11`	`11`	`exists(PhiInstruction phi \|`
`12`	`12`	`phi = instr and`
`13`		`- result = max(Instruction def \| def = phi.getAnOperandDefinitionInstruction() \| getConstantValueToPhi(def)) and`
`14`		`- result = min(Instruction def \| def = phi.getAnOperandDefinitionInstruction() \| getConstantValueToPhi(def))`
	`13`	`+ result = max(Instruction def \| def = phi.getAnInput() \| getConstantValueToPhi(def)) and`
	`14`	`+ result = min(Instruction def \| def = phi.getAnInput() \| getConstantValueToPhi(def))`
`15`	`15`	`)`
`16`	`16`	`}`
`17`	`17`
`18`	`18`	`pragma[noinline]`
`19`	`19`	`int getConstantValueToPhi(Instruction def) {`
`20`	`20`	`exists(PhiInstruction phi \|`
`21`	`21`	`result = getConstantValue(def) and`
`22`		`- def = phi.getAnOperandDefinitionInstruction()`
	`22`	`+ def = phi.getAnInput()`
`23`	`23`	`)`
`24`	`24`	`}`
`25`	`25`