From ff2a1c69d87968c69d7c131b5bbbba48d62453ce Mon Sep 17 00:00:00 2001
From: Mikhail Kocharmin <xnpster@yandex.ru>
Date: Wed, 10 Apr 2024 18:58:46 +0300
Subject: [PATCH] dead code: fix for entry statements, improve perfomance

---
 sapfor/experts/Sapfor_2017/_src/Sapfor.cpp                | 3 ++-
 .../Sapfor_2017/_src/Transformations/dead_code.cpp        | 8 ++++++--
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/sapfor/experts/Sapfor_2017/_src/Sapfor.cpp b/sapfor/experts/Sapfor_2017/_src/Sapfor.cpp
index e17ee2c..a99aa49 100644
--- a/sapfor/experts/Sapfor_2017/_src/Sapfor.cpp
+++ b/sapfor/experts/Sapfor_2017/_src/Sapfor.cpp
@@ -1028,7 +1028,8 @@ static bool runAnalysis(SgProject &project, const int curr_regime, const bool ne
         {
             auto funcsForFile = getObjectForFileFromMap(file_name, allFuncInfo);
             for (auto& func : funcsForFile)
-                removeDeadCode(func->funcPointer, allFuncInfo, commonBlocks);
+                if(func->funcPointer->variant() != ENTRY_STAT)
+                    removeDeadCode(func->funcPointer, allFuncInfo, commonBlocks);
         }
         else if (curr_regime == TEST_PASS)
         {
diff --git a/sapfor/experts/Sapfor_2017/_src/Transformations/dead_code.cpp b/sapfor/experts/Sapfor_2017/_src/Transformations/dead_code.cpp
index 5befc48..1e11a48 100644
--- a/sapfor/experts/Sapfor_2017/_src/Transformations/dead_code.cpp
+++ b/sapfor/experts/Sapfor_2017/_src/Transformations/dead_code.cpp
@@ -228,7 +228,9 @@ public:
             updated |= updateNextNotEmpty();
 
         updated |= updateJumpStatus();
-        updated |= this->forwardData({ });
+
+        if(updated)
+            this->forwardData({ });
 
         return updated;
     }
@@ -316,6 +318,7 @@ public:
     {
         setBlock(block);
         useful.resize(block->getInstructions().size(), false);
+        this->forwardData({ });
     }
     
     const vector<bool>& getResult() { return useful; }
@@ -371,7 +374,8 @@ void removeDeadCode(SgStatement* func,
     set<SAPFOR::BasicBlock*> reachable;
 
     for (auto b : cfg_pair.second)
-        if(b->getInstructions().front()->isHeader())
+        if(b->getInstructions().front()->isHeader() || 
+           b->getInstructions().front()->getInstruction()->getOperation() == SAPFOR::CFG_OP::ENTRY)
             reachable.insert(b);
 
     set<SAPFOR::BasicBlock*> worklist = reachable;