C++/C#: Sync identical files

Author: MathiasVP

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

@@ -61,14 +61,12 @@ newtype TValueNumber =
  */
 class CongruentCopyInstruction extends CopyInstruction {
   CongruentCopyInstruction() {
-    strictcount(this.getSourceValueOperand().getDefinitionOverlap()) = 1 and
     this.getSourceValueOperand().getDefinitionOverlap() instanceof MustExactlyOverlap
   }
 }
 
 class LoadTotalOverlapInstruction extends LoadInstruction {
   LoadTotalOverlapInstruction() {
-    strictcount(this.getSourceValueOperand().getDefinitionOverlap()) = 1 and
     this.getSourceValueOperand().getDefinitionOverlap() instanceof MustTotallyOverlap
   }
 }

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

@@ -61,14 +61,12 @@ newtype TValueNumber =
  */
 class CongruentCopyInstruction extends CopyInstruction {
   CongruentCopyInstruction() {
-    strictcount(this.getSourceValueOperand().getDefinitionOverlap()) = 1 and
     this.getSourceValueOperand().getDefinitionOverlap() instanceof MustExactlyOverlap
   }
 }
 
 class LoadTotalOverlapInstruction extends LoadInstruction {
   LoadTotalOverlapInstruction() {
-    strictcount(this.getSourceValueOperand().getDefinitionOverlap()) = 1 and
     this.getSourceValueOperand().getDefinitionOverlap() instanceof MustTotallyOverlap
   }
 }

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

@@ -96,7 +96,7 @@ private module Cached {
   }
 
   cached
-  Instruction getMemoryOperandDefinition(
+  private Instruction getMemoryOperandDefinition0(
     Instruction instruction, MemoryOperandTag tag, Overlap overlap
   ) {
     exists(OldInstruction oldInstruction, OldIR::NonPhiMemoryOperand oldOperand |
@@ -142,6 +142,19 @@ private module Cached {
     overlap instanceof MustExactlyOverlap
   }
 
+  cached
+  Instruction getMemoryOperandDefinition(
+    Instruction instruction, MemoryOperandTag tag, Overlap overlap
+  ) {
+    // getMemoryOperandDefinition0 currently has a bug where it can match with multiple overlaps.
+    // This predicate ensures that the chosen overlap is the most conservative if there's any doubt.
+    result = getMemoryOperandDefinition0(instruction, tag, overlap) and
+    not (
+      overlap instanceof MustExactlyOverlap and
+      exists(MustTotallyOverlap o | exists(getMemoryOperandDefinition0(instruction, tag, o)))
+    )
+  }
+
   /**
    * Holds if `instr` is part of a cycle in the operand graph that doesn't go
    * through a phi instruction and therefore should be impossible.

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

@@ -96,7 +96,7 @@ private module Cached {
   }
 
   cached
-  Instruction getMemoryOperandDefinition(
+  private Instruction getMemoryOperandDefinition0(
     Instruction instruction, MemoryOperandTag tag, Overlap overlap
   ) {
     exists(OldInstruction oldInstruction, OldIR::NonPhiMemoryOperand oldOperand |
@@ -142,6 +142,19 @@ private module Cached {
     overlap instanceof MustExactlyOverlap
   }
 
+  cached
+  Instruction getMemoryOperandDefinition(
+    Instruction instruction, MemoryOperandTag tag, Overlap overlap
+  ) {
+    // getMemoryOperandDefinition0 currently has a bug where it can match with multiple overlaps.
+    // This predicate ensures that the chosen overlap is the most conservative if there's any doubt.
+    result = getMemoryOperandDefinition0(instruction, tag, overlap) and
+    not (
+      overlap instanceof MustExactlyOverlap and
+      exists(MustTotallyOverlap o | exists(getMemoryOperandDefinition0(instruction, tag, o)))
+    )
+  }
+
   /**
    * Holds if `instr` is part of a cycle in the operand graph that doesn't go
    * through a phi instruction and therefore should be impossible.