C++: Replace 'if p() then q() else none()' with a conjunction.

cpp/ql/lib/semmle/code/cpp/Declaration.qll

@@ -275,9 +275,8 @@ class Declaration extends Locatable, @declaration {
    * `getTemplateArgumentKind(0)`.
    */
   final Locatable getTemplateArgumentKind(int index) {
-    if exists(getTemplateArgumentValue(index))
-    then result = getTemplateArgumentType(index)
-    else none()
+    exists(getTemplateArgumentValue(index)) and
+    result = getTemplateArgumentType(index)
   }
 
   /** Gets the number of template arguments for this declaration. */

cpp/ql/lib/semmle/code/cpp/controlflow/internal/ConstantExprs.qll

@@ -344,14 +344,13 @@ private int convertIntToType(int val, IntegralType t) {
   then if val = 0 then result = 0 else result = 1
   else
     if t.isUnsigned()
-    then if val >= 0 and val.bitShiftRight(t.getSize() * 8) = 0 then result = val else none()
+    then val >= 0 and val.bitShiftRight(t.getSize() * 8) = 0 and result = val
     else
       if val >= 0 and val.bitShiftRight(t.getSize() * 8 - 1) = 0
       then result = val
-      else
-        if (-(val + 1)).bitShiftRight(t.getSize() * 8 - 1) = 0
-        then result = val
-        else none()
+      else (
+        (-(val + 1)).bitShiftRight(t.getSize() * 8 - 1) = 0 and result = val
+      )
 }
 
 /**

cpp/ql/lib/semmle/code/cpp/ir/internal/IntegerInterval.qll

@@ -18,10 +18,11 @@ Overlap getOverlap(IntValue defStart, IntValue defEnd, IntValue useStart, IntVal
   else
     if isLE(defStart, useStart) and isGE(defEnd, useEnd)
     then result instanceof MustTotallyOverlap
-    else
-      if isLE(defEnd, useStart) or isGE(defStart, useEnd)
-      then none()
-      else result instanceof MayPartiallyOverlap
+    else (
+      not isLE(defEnd, useStart) and
+      not isGE(defStart, useEnd) and
+      result instanceof MayPartiallyOverlap
+    )
 }
 
 /**

cpp/ql/lib/semmle/code/cpp/security/BufferWrite.qll

@@ -365,7 +365,7 @@ class GetsBW extends BufferWriteCall {
   /**
    * Gets the index of the parameter that is the maximum number of characters to be read.
    */
-  int getParamSize() { if exists(getArgument(1)) then result = 1 else none() }
+  int getParamSize() { exists(getArgument(1)) and result = 1 }
 
   override Type getBufferType() { result = this.getTarget().getParameter(0).getUnspecifiedType() }