Address review comment.

Author: pratikashar

IGC/Compiler/Optimizer/OpenCLPasses/PrivateMemory/PrivateMemoryResolution.cpp

@@ -814,8 +814,6 @@ bool PrivateMemoryResolution::resolveAllocaInstructions(bool privateOnStack)
 
     // Construct an empty DebugLoc.
     IF_DEBUG_INFO(DebugLoc entryDebugLoc);
-    // Assign with the function location if available.
-    IF_DEBUG_INFO_IF(DISubprogram *subprogram = m_currFunction->getSubprogram(), entryDebugLoc = DebugLoc::get(subprogram->getLine(), 0, subprogram););
     IF_DEBUG_INFO(entryBuilder.SetCurrentDebugLocation(entryDebugLoc));
 
     if (privateOnStack)
@@ -922,7 +920,7 @@ bool PrivateMemoryResolution::resolveAllocaInstructions(bool privateOnStack)
             // correctly. So instead, we set DebugLoc for the instructions generated by lowering
             // alloca to mark that they are part of the prologue.
             // Note: As per Amjad, later LLVM version has a fix for this in llvm/lib/Transforms/Utils/InlineFunction.cpp.
-            IF_DEBUG_INFO(builder.SetCurrentDebugLocation(entryDebugLoc));
+            IF_DEBUG_INFO(builder.SetCurrentDebugLocation(pAI->getDebugLoc()));
 
             // Get buffer information from the analysis
             unsigned int scalarBufferOffset = m_ModAllocaInfo->getConstBufferOffset(pAI);

IGC/DebugInfo/DwarfDebug.hpp

@@ -634,7 +634,29 @@ namespace IGC
 
         // Store label for each %ip
         llvm::DenseMap<unsigned int, llvm::MCSymbol*> LabelsBeforeIp;
+
+        // function, inlinedAt
+        llvm::DenseMap<llvm::DISubprogram*, llvm::SmallPtrSet <llvm::DILocation*, 5>> prologueEnd;
     public:
+        bool prologueEndExists(llvm::DISubprogram* sp, llvm::DILocation* dl, bool add)
+        {
+            auto it = prologueEnd.find(sp);
+            if (it == prologueEnd.end())
+            {
+                if (add)
+                    prologueEnd[sp].insert(dl);
+                return false;
+            }
+
+            if (it->second.find(dl) != it->second.end())
+                return true;
+
+            if (add)
+                it->second.insert(dl);
+
+            return false;
+        }
+
         bool isStmtExists(unsigned int line, llvm::DILocation* inlinedAt, bool add)
         {
             auto it = isStmtSet.find(line);

IGC/DebugInfo/VISADebugEmitter.cpp

@@ -48,6 +48,7 @@ IN THE SOFTWARE.
 #include "DwarfDebug.hpp"
 #include "StreamEmitter.hpp"
 #include "VISAModule.hpp"
+#include "GenISAIntrinsics/GenIntrinsicInst.h"
 
 #include "Probe/Assertion.h"
 #include "secure_mem.h"
@@ -232,7 +233,8 @@ std::vector<char> DebugEmitter::Finalize(bool finalize, DbgDecoder* decodedDbg)
                 }
             }
 
-            if (instIt != VISAIndexToInst.end())
+            if (instIt != VISAIndexToInst.end() &&
+                m_pVISAModule->IsExecutableInst(*instIt->second))
             {
                 auto loc = instIt->second->getDebugLoc();
                 if (loc)
@@ -247,6 +249,12 @@ std::vector<char> DebugEmitter::Finalize(bool finalize, DbgDecoder* decodedDbg)
                         {
                             Flags |= DWARF2_FLAG_IS_STMT;
                         }
+
+                        if (!m_pDwarfDebug->prologueEndExists(loc.get()->getScope()->getSubprogram(),
+                            loc.getInlinedAt(), true))
+                        {
+                            Flags |= DWARF2_FLAG_PROLOGUE_END;
+                        }
                         m_pStreamEmitter->EmitDwarfLocDirective(src, loc.getLine(), loc.getCol(), Flags, 0, 0, scope->getFilename());
 
                         prevSrcLoc = loc;

IGC/DebugInfo/VISAModule.cpp

@@ -239,6 +239,21 @@ const std::string& VISAModule::GetTargetTriple() const
     return m_triple;
 }
 
+bool VISAModule::IsExecutableInst(const llvm::Instruction& inst)
+{
+    // Return false if inst is dbg info intrinsic or if it is
+    // catch all intrinsic. In both of these cases, we dont want
+    // to emit associated debug loc since there is no machine
+    // code generated for them.
+    if (IsCatchAllIntrinsic(&inst))
+        return false;
+
+    if (llvm::isa<DbgInfoIntrinsic>(inst))
+        return false;
+
+    return true;
+}
+
 void VISAModule::buildDirectElfMaps(const IGC::DbgDecoder& VD)
 {
     const auto* co = getCompileUnit(VD);
@@ -248,6 +263,10 @@ void VISAModule::buildDirectElfMaps(const IGC::DbgDecoder& VD)
     {
         const Instruction* pInst = *II;
 
+        // store VISA mapping only if pInst generates Gen code
+        if (!IsExecutableInst(*pInst))
+            continue;
+
         InstInfoMap::const_iterator itr = m_instInfoMap.find(pInst);
         if (itr == m_instInfoMap.end())
             continue;

IGC/DebugInfo/VISAModule.hpp

@@ -439,6 +439,9 @@ namespace IGC
             return false;
         }
 
+        ///  @brief return false if inst is a placeholder instruction
+        bool IsExecutableInst(const llvm::Instruction& inst);
+
         bool isDirectElfInput = false;
         // Store first VISA index->llvm::Instruction mapping
         std::map<unsigned int, const llvm::Instruction*> VISAIndexToInst;