From 987b524193b096e6b7a05d02ecca782987d7dc5a Mon Sep 17 00:00:00 2001
From: caheckman <48068198+caheckman@users.noreply.github.com>
Date: Tue, 31 May 2022 20:32:35 -0400
Subject: [PATCH] GP-2082 Guarantee only a single switch edge is labeled
 default

---
 .../Features/Decompiler/src/decompile/cpp/block.cc   | 12 ++++++++++++
 .../Features/Decompiler/src/decompile/cpp/block.hh   |  2 +-
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/Ghidra/Features/Decompiler/src/decompile/cpp/block.cc b/Ghidra/Features/Decompiler/src/decompile/cpp/block.cc
index 985e3e97db..201595af16 100644
--- a/Ghidra/Features/Decompiler/src/decompile/cpp/block.cc
+++ b/Ghidra/Features/Decompiler/src/decompile/cpp/block.cc
@@ -301,6 +301,18 @@ void FlowBlock::setGotoBranch(int4 i)
   outofthis[i].point->flags |= f_interior_gotoin;
 }
 
+/// The switch can have exactly 1 default edge, so we make sure other edges are not marked.
+/// \param pos is the index of the \e out edge that should be the default
+void FlowBlock::setDefaultSwitch(int4 pos)
+
+{
+  for(int4 i=0;i<outofthis.size();++i) {
+    if (isDefaultBranch(i))
+      clearOutEdgeFlag(i, f_defaultswitch_edge);	// Clear any previous flag
+  }
+  setOutEdgeFlag(pos,f_defaultswitch_edge);
+}
+
 /// \b return \b true if block is the target of a jump
 bool FlowBlock::isJumpTarget(void) const
 
diff --git a/Ghidra/Features/Decompiler/src/decompile/cpp/block.hh b/Ghidra/Features/Decompiler/src/decompile/cpp/block.hh
index fbf626f8e4..b071e75b73 100644
--- a/Ghidra/Features/Decompiler/src/decompile/cpp/block.hh
+++ b/Ghidra/Features/Decompiler/src/decompile/cpp/block.hh
@@ -190,7 +190,7 @@ public:
   void setVisitCount(int4 i) { visitcount = i; }	///< Set the number of times this block has been visited
   int4 getVisitCount(void) const { return visitcount; }	///< Get the count of visits
   void setGotoBranch(int4 i);				///< Mark a \e goto branch
-  void setDefaultSwitch(int4 i) { setOutEdgeFlag(i,f_defaultswitch_edge); }	///< Mark an edge as the switch default
+  void setDefaultSwitch(int4 pos);			///< Mark an edge as the switch default
   bool isMark(void) const { return ((flags&f_mark)!=0); }	///< Return \b true if \b this block has been marked
   void setMark(void) { flags |= f_mark; }			///< Mark \b this block
   void clearMark(void) { flags &= ~f_mark; }			///< Clear any mark on \b this block