skip printf strings in constant encoding

Author: dmitryryintel

IGC/VectorCompiler/lib/GenXCodeGen/GenXCisaBuilder.cpp

@@ -2668,16 +2668,10 @@ bool GenXKernelBuilder::buildMainInst(Instruction *Inst, BaleInfo BI,
   } else if (auto LI = dyn_cast<LoadInst>(Inst)) {
     (void)LI; // no code generated
   } else if (auto GEPI = dyn_cast<GetElementPtrInst>(Inst)) {
-    // check if gepi def is used in intrinsic, otherwise report error
-    auto GepiChecker = [](Use &ui) {
-      auto ci = cast<CallInst>(ui.getUser());
-      Function *Callee = ci->getCalledFunction();
-      unsigned IntrinID = GenXIntrinsic::getAnyIntrinsicID(Callee);
-      return (IntrinID == GenXIntrinsic::genx_print_format_index);
-    };
-    if (!std::all_of(GEPI->use_begin(), GEPI->use_end(), GepiChecker)) {
-      report_fatal_error("gep is supported only for printf");
-    }
+    // Skip genx.print.format.index GEP here.
+    IGC_ASSERT_MESSAGE(isPrintFormatIndexGEP(*GEPI),
+                       "only genx.print.format.index src GEP can still be "
+                       "present at this stage");
 #if (LLVM_VERSION_MAJOR > 8)
   } else if (UnaryOperator *UO = dyn_cast<UnaryOperator>(Inst)) {
     buildUnaryOperator(UO, BI, Mod, DstDesc);

IGC/VectorCompiler/lib/GenXCodeGen/GenXOCLRuntimeInfo.cpp

@@ -531,11 +531,22 @@ static void appendGlobalVariableData(
   Accumulator.append(&GV, Data.begin(), Data.end());
 }
 
-ModuleDataT getModuleData(const Module &M) {
+// Not every global variable is a real global variable and should be encoded
+// as a global variable.
+// GenX volatile and printf strings are exclusion for now.
+static bool isRealGlobalVariable(const GlobalVariable &GV) {
+  if (GV.hasAttribute("genx_volatile"))
+    return false;
+  return std::any_of(GV.user_begin(), GV.user_end(), [](const User *Usr) {
+    return !genx::isPrintFormatIndexGEP(*Usr);
+  });
+}
+
+static ModuleDataT getModuleData(const Module &M) {
   genx::BinaryDataAccumulator<const GlobalVariable *> ConstantData;
   genx::BinaryDataAccumulator<const GlobalVariable *> GlobalData;
   for (auto &GV : M.globals()) {
-    if (GV.hasAttribute("genx_volatile"))
+    if (!isRealGlobalVariable(GV))
       continue;
     if (GV.isConstant())
       appendGlobalVariableData(ConstantData, GV);

IGC/VectorCompiler/lib/GenXCodeGen/GenXUtil.cpp

@@ -1988,3 +1988,22 @@ unsigned genx::getNumGRFsPerIndirectForRegion(const genx::Region &R,
   }
   return 1;
 }
+
+bool genx::isPrintFormatIndexGEP(const GetElementPtrInst &GEP) {
+  return std::all_of(GEP.user_begin(), GEP.user_end(), [](const User *Usr) {
+    if (!isa<CallInst>(Usr))
+      return false;
+    const Function *Callee = cast<CallInst>(Usr)->getCalledFunction();
+    if (!Callee)
+      return false;
+    auto IntrinID = GenXIntrinsic::getAnyIntrinsicID(Callee);
+    return (IntrinID == GenXIntrinsic::genx_print_format_index);
+  });
+}
+
+// Just for convenience.
+bool genx::isPrintFormatIndexGEP(const Value &V) {
+  if (!isa<GetElementPtrInst>(V))
+    return false;
+  return isPrintFormatIndexGEP(cast<GetElementPtrInst>(V));
+}

IGC/VectorCompiler/lib/GenXCodeGen/GenXUtil.h

@@ -637,6 +637,13 @@ template <typename KeyT> class BinaryDataAccumulator {
   std::vector<char> emitConsolidatedData() && { return std::move(Data); }
 };
 
+// There's a special case of GEP when all its users are genx.print.format.index
+// intrinsics. Such GEPs live until CisaBuilder and then handled as part of
+// genx.print.format.index intrinsic.
+// This function checks whether \p GEP is a such GEP.
+bool isPrintFormatIndexGEP(const GetElementPtrInst &GEP);
+bool isPrintFormatIndexGEP(const Value &V);
+
 } // namespace genx
 } // namespace llvm