From a6e96dcb93bb3353fe8170ad94ca94bdf5ccf1ce Mon Sep 17 00:00:00 2001
From: Andrea Gussoni <andreagus@rev.ng>
Date: Tue, 30 Apr 2024 15:40:58 +0200
Subject: [PATCH] FallThroughScope: remove `SwitchBreak` type

A `SwitchBreak` node should not have a specific associated
`FallThroughScopeType`, since its semantics represent the fact of a
`case` of the `switch` with no associated statements, and thus can be
represented with the `FallThrough` behavior.
---
 lib/RestructureCFG/FallThroughScopeAnalysis.cpp | 5 ++++-
 lib/RestructureCFG/FallThroughScopeAnalysis.h   | 1 -
 lib/RestructureCFG/PromoteCallNoReturn.cpp      | 3 +--
 3 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/lib/RestructureCFG/FallThroughScopeAnalysis.cpp b/lib/RestructureCFG/FallThroughScopeAnalysis.cpp
index 54e1b215a..dea17210d 100644
--- a/lib/RestructureCFG/FallThroughScopeAnalysis.cpp
+++ b/lib/RestructureCFG/FallThroughScopeAnalysis.cpp
@@ -227,7 +227,10 @@ fallThroughScopeImpl(const model::Binary &Model,
     rc_return FallThroughScopeType::FallThrough;
   } break;
   case ASTNode::NK_SwitchBreak: {
-    rc_return FallThroughScopeType::SwitchBreak;
+
+    // `The `SwitchBreak` represents the fact that we fallthrough from the
+    // switch out
+    rc_return FallThroughScopeType::FallThrough;
   } break;
   case ASTNode::NK_Continue: {
     rc_return FallThroughScopeType::Continue;
diff --git a/lib/RestructureCFG/FallThroughScopeAnalysis.h b/lib/RestructureCFG/FallThroughScopeAnalysis.h
index d36d4f26b..b9a1b19bb 100644
--- a/lib/RestructureCFG/FallThroughScopeAnalysis.h
+++ b/lib/RestructureCFG/FallThroughScopeAnalysis.h
@@ -21,7 +21,6 @@ enum class FallThroughScopeType {
   Return,
   Continue,
   LoopBreak,
-  SwitchBreak,
 };
 
 using FallThroughScopeTypeMap = std::map<const ASTNode *, FallThroughScopeType>;
diff --git a/lib/RestructureCFG/PromoteCallNoReturn.cpp b/lib/RestructureCFG/PromoteCallNoReturn.cpp
index 7ff37abe7..879d033ed 100644
--- a/lib/RestructureCFG/PromoteCallNoReturn.cpp
+++ b/lib/RestructureCFG/PromoteCallNoReturn.cpp
@@ -30,8 +30,7 @@ static bool isPreferredAsFallThrough(FallThroughScopeType Element) {
   switch (Element) {
   case FallThroughScopeType::Return:
   case FallThroughScopeType::Continue:
-  case FallThroughScopeType::LoopBreak:
-  case FallThroughScopeType::SwitchBreak: {
+  case FallThroughScopeType::LoopBreak: {
     return true;
   } break;
   case FallThroughScopeType::FallThrough: