Merge pull request #1845 from AndreiDiaconu1/ircsharp-compiler-generated

C# IR: Framework for translating compiler generated elements

Author: calumgrant

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

@@ -7,6 +7,7 @@ private import TranslatedCondition
 private import TranslatedElement
 private import TranslatedExpr
 private import TranslatedStmt
+private import desugar.Foreach
 private import TranslatedFunction
 private import semmle.code.csharp.ir.Util
 private import semmle.code.csharp.ir.internal.IRCSharpLanguage as Language
@@ -136,6 +137,17 @@ private module Cached {
       )
     )
     or
+    // Compiler generated foreach while loop:
+    // Same as above
+    exists(TranslatedForeachWhile s |
+      result = s.getFirstInstruction() and
+      exists(TranslatedElement inBody, InstructionTag tag |
+        result = inBody.getInstructionSuccessor(tag, kind) and
+        exists(TranslatedElement body | body = s.getBody() | inBody = body.getAChild*()) and
+        instruction = inBody.getInstruction(tag)
+      )
+    )
+    or
     // Do-while loop:
     // The back edge should be the edge(s) from the condition to the
     // body. This ensures that it's the back edge that will be pruned in a `do

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

@@ -1,9 +1,6 @@
 import csharp
 import semmle.code.csharp.ir.Util
 
-//private predicate fieldIsInitialized(Field field) {
-//  exists(field.getInitializer())
-//}
 private predicate elementIsInitialized(int elementIndex) {
   exists(ArrayInitWithMod initList | initList.isInitialized(elementIndex))
 }
@@ -54,6 +51,7 @@ newtype TInstructionTag =
   BoolConversionConstantTag() or
   BoolConversionCompareTag() or
   LoadTag() or // Implicit load due to lvalue-to-rvalue conversion
+  AddressTag() or
   CatchTag() or
   ThrowTag() or
   UnwindTag() or
@@ -192,16 +190,8 @@ string getInstructionTagId(TInstructionTag tag) {
   or
   tag = GeneratedBranchTag() and result = "GeneratedBranchTag"
   or
-  // TODO: Reread
-  //  exists(Field field, Class cls, int index, string tagName |
-  //    field = cls.getCanonicalMember(index) and
-  //    (
-  //      tag = InitializerFieldAddressTag(field) and tagName = "InitFieldAddr" or
-  //      tag = InitializerFieldDefaultValueTag(field) and tagName = "InitFieldDefVal" or
-  //      tag = InitializerFieldDefaultValueStoreTag(field) and tagName = "InitFieldDefValStore"
-  //    ) and
-  //    result = tagName + "(" + index + ")"
-  //  ) or
+  tag = AddressTag() and result = "AddressTag"
+  or
   exists(int index, string tagName |
     (
       tag = InitializerElementIndexTag(index) and tagName = "InitElemIndex"