From 580226cfa0bcb5788410b93e4590ac642b7dd2aa Mon Sep 17 00:00:00 2001
From: caheckman <48068198+caheckman@users.noreply.github.com>
Date: Mon, 30 Sep 2024 23:02:15 +0000
Subject: [PATCH] GP-4899 Full check for switch target in isDoNothing

---
 .../Features/Decompiler/src/decompile/cpp/block.cc  | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/Ghidra/Features/Decompiler/src/decompile/cpp/block.cc b/Ghidra/Features/Decompiler/src/decompile/cpp/block.cc
index a24283890b..46da66dfa2 100644
--- a/Ghidra/Features/Decompiler/src/decompile/cpp/block.cc
+++ b/Ghidra/Features/Decompiler/src/decompile/cpp/block.cc
@@ -2574,9 +2574,16 @@ bool BlockBasic::isDoNothing(void) const
   if (sizeIn() == 0) return false; // A block that does nothing but
 				// is a starting block, may need to be a
 				// placeholder for global(persistent) vars
-  if ((sizeIn()==1)&&(getIn(0)->isSwitchOut())) {
-    if (getOut(0)->sizeIn() > 1)
-      return false;		// Don't remove switch targets
+  for(int4 i=0;i<sizeIn();++i) {
+    const FlowBlock *switchbl = getIn(i);
+    if (!switchbl->isSwitchOut()) continue;
+    if (switchbl->sizeOut() > 1) {
+      // This block is a switch target
+      if (getOut(0)->sizeIn() > 1) {	// Multiple edges coming together
+					// Switch edge may still be propagating a unique value
+	return false;			// Don't remove it
+      }
+    }
   }
   PcodeOp *lastop = lastOp();
   if ((lastop != (PcodeOp *)0)&&(lastop->code()==CPUI_BRANCHIND))