ZEBinary: avoid generate .ze_info section if it's empty

Add ZEInfoBuilder::empty to check if there's nothing in zeinfo
Avoid generating .ze_info section in ZEBinary if it's empty

Author: DianaChen

IGC/AdaptorOCL/OCL/sp/zebin_builder.cpp

@@ -774,7 +774,8 @@ void ZEBinaryBuilder::addElfSections(void* elfBin, size_t elfSize)
 
 void ZEBinaryBuilder::getBinaryObject(llvm::raw_pwrite_stream& os)
 {
-    mBuilder.addSectionZEInfo(mZEInfoBuilder.getZEInfoContainer());
+    if (!mZEInfoBuilder.empty())
+        mBuilder.addSectionZEInfo(mZEInfoBuilder.getZEInfoContainer());
     mBuilder.finalize(os);
 }
 

IGC/ZEBinWriter/zebin/source/ZEELFObjectBuilder.cpp

@@ -246,7 +246,7 @@ ZEELFObjectBuilder::addSectionDebug(std::string name, const uint8_t* data, uint6
 void
 ZEELFObjectBuilder::addSectionZEInfo(zeInfoContainer& zeInfo)
 {
-    // every object should have exactly one ze_info section
+    // every object should have at most one ze_info section
     IGC_ASSERT(!m_zeInfoSection);
     m_zeInfoSection.reset(new ZEInfoSection(zeInfo, m_sectionIdCount));
     ++m_sectionIdCount;
@@ -803,14 +803,11 @@ void ELFWriter::createSectionHdrEntries()
     }
 
     // .ze_info
-    // every object must have exactly one ze_info section
     if (m_ObjBuilder.m_zeInfoSection) {
         createSectionHdrEntry(m_ObjBuilder.m_ZEInfoName, SHT_ZEBIN_ZEINFO,
             m_ObjBuilder.m_zeInfoSection.get());
         ++index;
     }
-    else
-        IGC_ASSERT(0);
 
     // .strtab
     m_StringTableIndex = index;
@@ -826,6 +823,11 @@ zeInfoKernel& ZEInfoBuilder::createKernel(const std::string& name)
     return k;
 }
 
+bool ZEInfoBuilder::empty() const
+{
+    return mContainer.kernels.empty();
+}
+
 // addPayloadArgumentByPointer - add explicit kernel argument with pointer
 // type into given arg_list
 zeInfoPayloadArgument& ZEInfoBuilder::addPayloadArgumentByPointer(

IGC/ZEBinWriter/zebin/source/ZEELFObjectBuilder.hpp

@@ -363,7 +363,7 @@ class ZEELFObjectBuilder {
     // current section id
     SectionID m_sectionIdCount = 0;
 
-    // every ze object contains only one ze_info section
+    // every ze object contains at most one ze_info section
     std::unique_ptr<ZEInfoSection> m_zeInfoSection;
     SymbolListTy m_localSymbols;
     SymbolListTy m_globalSymbols;
@@ -381,6 +381,9 @@ class ZEInfoBuilder {
     zeInfoContainer& getZEInfoContainer()             { return mContainer; }
     const zeInfoContainer& getZEInfoContainer() const { return mContainer; }
 
+    // empty - return true if there is no kernel/function info in it
+    bool empty() const;
+
     /// --------- Helper functions for setup zeinfo contents -------------- ///
     // createKernel - create a zeInfoKernel and add it into zeInfoContainer
     zeInfoKernel& createKernel(const std::string& name);