Partial change to fix support for debug info for stack call functions. Emission of .debug_frames is pending.

Change-Id: I63d02954cb2bc50b62c84486744a6ec22642382d

Author: pratikashar

IGC/Compiler/CISACodeGen/DebugInfo.cpp

@@ -111,9 +111,27 @@ bool DebugInfoPass::runOnModule(llvm::Module& M)
         m_pDebugEmitter = m_currShader->diData->m_pDebugEmitter;
         std::vector<std::pair<unsigned int, std::pair<llvm::Function*, IGC::VISAModule*>>> sortedVISAModules;
 
+        // Sort modules in order of their placement in binary
+        DbgDecoder decodedDbg(m_currShader->ProgramOutput()->m_debugDataGenISA);
+        auto getLastGenOff = [&decodedDbg](IGC::VISAModule* v)
+        {
+            unsigned int genOff = 0;
+
+            for (auto& item : decodedDbg.compiledObjs)
+            {
+                auto& name = item.kernelName;
+                auto firstInst = (v->GetInstInfoMap()->begin())->first;
+                auto funcName = firstInst->getParent()->getParent()->getName();
+                if (funcName.compare(name) == 0)
+                    genOff = item.CISAIndexMap.back().second;
+            }
+
+            return genOff;
+        };
+
         for (auto& m : m_currShader->diData->m_VISAModules)
         {
-            auto lastVISAId = m.second->GetCurrentVISAId();
+            auto lastVISAId = getLastGenOff(m.second);
             sortedVISAModules.push_back(std::make_pair(lastVISAId, std::make_pair(m.first, m.second)));
         }
 

IGC/Compiler/DebugInfo/DwarfDebug.cpp

@@ -2334,6 +2334,9 @@ void DwarfDebug::emitDebugLoc()
             }
         }
     }
+
+    DotDebugLocEntries.clear();
+
 #else
     for (SmallVectorImpl<DotDebugLocEntry>::iterator
            I = DotDebugLocEntries.begin(), E = DotDebugLocEntries.end();

IGC/Compiler/DebugInfo/DwarfDebug.hpp

@@ -661,7 +661,14 @@ namespace IGC
         unsigned int lowPc = 0, highPc = 0;
 
         DbgDecoder* getDecodedDbg() { return decodedDbg; }
-        void setDecodedDbg(DbgDecoder* d) { decodedDbg = d; }
+        void setDecodedDbg(DbgDecoder* d)
+        {
+            if (decodedDbg)
+            {
+                delete decodedDbg;
+            }
+            decodedDbg = d;
+        }
         unsigned int CopyDebugLoc(unsigned int offset);
 
     private:

IGC/Compiler/DebugInfo/VISADebugEmitter.cpp

@@ -215,6 +215,7 @@ void DebugEmitter::Finalize(void *&pBuffer, unsigned int &size, bool finalize)
         m_pDwarfDebug->setDecodedDbg(decodedDbg);
 
         m_pVISAModule->buildDirectElfMaps();
+        auto co = m_pVISAModule->getCompileUnit();
 
         // Emit src line mapping directly instead of
         // relying on dbgmerge. elf generated will have
@@ -226,20 +227,30 @@ void DebugEmitter::Finalize(void *&pBuffer, unsigned int &size, bool finalize)
         unsigned int prevLastGenOff = lastGenOff;
         m_pDwarfDebug->lowPc = lastGenOff;
 
-        for (auto item : m_pVISAModule->GenISAToVISAIndex)
+        if (co->subs.size() == 0)
         {
-            if ((item.first > lastGenOff) || ((item.first | lastGenOff) == 0))
+            GenISAToVISAIndex = m_pVISAModule->GenISAToVISAIndex;
+            if(GenISAToVISAIndex.size() > 0)
+                lastGenOff = GenISAToVISAIndex.back().first;
+            m_pDwarfDebug->lowPc = co->relocOffset;
+        }
+        else
+        {
+            for (auto item : m_pVISAModule->GenISAToVISAIndex)
             {
-                if (item.second <= subEnd ||
-                    item.second == 0xffffffff)
+                if ((item.first > lastGenOff) || ((item.first | lastGenOff) == 0))
                 {
-                    GenISAToVISAIndex.push_back(item);
-                    lastGenOff = item.first;
-                    continue;
-                }
+                    if (item.second <= subEnd ||
+                        item.second == 0xffffffff)
+                    {
+                        GenISAToVISAIndex.push_back(item);
+                        lastGenOff = item.first;
+                        continue;
+                    }
 
-                if (item.second > subEnd)
-                    break;
+                    if (item.second > subEnd)
+                        break;
+                }
             }
         }