omit null entries

Author: bcardosolopes

mlir/include/mlir/Dialect/LLVMIR/LLVMAttrDefs.td

@@ -1371,16 +1371,11 @@ def ModuleFlagCGProfileEntryAttr
     ```
   }];
   let parameters = (
-    ins OptionalParameter<"std::optional<FlatSymbolRefAttr>">:$from,
-        OptionalParameter<"std::optional<FlatSymbolRefAttr>">:$to,
+    ins OptionalParameter<"FlatSymbolRefAttr">:$from,
+        OptionalParameter<"FlatSymbolRefAttr">:$to,
         "uint64_t":$count);
-  let assemblyFormat = [{
-    `<`
-      `from` `=` ($from^) : (`null`)? `,`
-      `to` `=` ($to^) : (`null`)? `,`
-      `count` `=` $count
-    `>`
-  }];
+
+  let assemblyFormat = "`<` struct(params) `>`";
 }
 
 //===----------------------------------------------------------------------===//

mlir/lib/Target/LLVMIR/Dialect/LLVMIR/LLVMToLLVMIRTranslation.cpp

@@ -284,12 +284,12 @@ convertModuleFlagValue(StringRef key, ArrayAttr arrayAttr,
       llvm::Metadata *fromMetadata =
           entry.getFrom()
               ? llvm::ValueAsMetadata::get(moduleTranslation.lookupFunction(
-                    entry.getFrom()->getValue()))
+                    entry.getFrom().getValue()))
               : nullptr;
       llvm::Metadata *toMetadata =
           entry.getTo()
               ? llvm::ValueAsMetadata::get(
-                    moduleTranslation.lookupFunction(entry.getTo()->getValue()))
+                    moduleTranslation.lookupFunction(entry.getTo().getValue()))
               : nullptr;
 
       llvm::Metadata *vals[] = {

mlir/lib/Target/LLVMIR/ModuleImport.cpp

@@ -521,14 +521,14 @@ void ModuleImport::addDebugIntrinsic(llvm::CallInst *intrinsic) {
 
 static Attribute convertCGProfileModuleFlagValue(ModuleOp mlirModule,
                                                  llvm::MDTuple *mdTuple) {
-  auto getFunctionSymbol =
-      [&](const llvm::MDOperand &funcMDO) -> std::optional<FlatSymbolRefAttr> {
+  auto getLLVMFunction =
+      [&](const llvm::MDOperand &funcMDO) -> llvm::Function * {
     auto *f = cast_or_null<llvm::ValueAsMetadata>(funcMDO);
     // nullptr is a valid value for the function pointer.
     if (!f)
-      return std::nullopt;
+      return nullptr;
     auto *llvmFn = cast<llvm::Function>(f->getValue()->stripPointerCasts());
-    return FlatSymbolRefAttr::get(mlirModule->getContext(), llvmFn->getName());
+    return llvmFn;
   };
 
   // Each tuple element becomes one ModuleFlagCGProfileEntryAttr.
@@ -539,9 +539,17 @@ static Attribute convertCGProfileModuleFlagValue(ModuleOp mlirModule,
     llvm::Constant *llvmConstant =
         cast<llvm::ConstantAsMetadata>(cgEntry->getOperand(2))->getValue();
     uint64_t count = cast<llvm::ConstantInt>(llvmConstant)->getZExtValue();
+    auto *fromFn = getLLVMFunction(cgEntry->getOperand(0));
+    auto *toFn = getLLVMFunction(cgEntry->getOperand(1));
+    // FlatSymbolRefAttr::get(mlirModule->getContext(), llvmFn->getName());
     cgProfile.push_back(ModuleFlagCGProfileEntryAttr::get(
-        mlirModule->getContext(), getFunctionSymbol(cgEntry->getOperand(0)),
-        getFunctionSymbol(cgEntry->getOperand(1)), count));
+        mlirModule->getContext(),
+        fromFn ? FlatSymbolRefAttr::get(mlirModule->getContext(),
+                                        fromFn->getName())
+               : nullptr,
+        toFn ? FlatSymbolRefAttr::get(mlirModule->getContext(), toFn->getName())
+             : nullptr,
+        count));
   }
   return ArrayAttr::get(mlirModule->getContext(), cgProfile);
 }

mlir/test/Dialect/LLVMIR/module-roundtrip.mlir

@@ -9,7 +9,7 @@ module {
                      #llvm.mlir.module_flag<override, "probe-stack", "inline-asm">,
                      #llvm.mlir.module_flag<append, "CG Profile", [
                        #llvm.cgprofile_entry<from = @from, to = @to, count = 222>,
-                       #llvm.cgprofile_entry<from = @from, to = null, count = 222>,
+                       #llvm.cgprofile_entry<from = @from, count = 222>,
                        #llvm.cgprofile_entry<from = @to, to = @from, count = 222>
                     ]>]
 }
@@ -23,6 +23,6 @@ module {
 // CHECK-SAME: #llvm.mlir.module_flag<override, "probe-stack", "inline-asm">,
 // CHECK-SAME: #llvm.mlir.module_flag<append, "CG Profile", [
 // CHECK-SAME: #llvm.cgprofile_entry<from = @from, to = @to, count = 222>,
-// CHECK-SAME: #llvm.cgprofile_entry<from = @from, to = null, count = 222>,
+// CHECK-SAME: #llvm.cgprofile_entry<from = @from, count = 222>,
 // CHECK-SAME: #llvm.cgprofile_entry<from = @to, to = @from, count = 222>
 // CHECK-SAME: ]>]

mlir/test/Target/LLVMIR/Import/module-flags.ll

@@ -41,6 +41,6 @@ declare void @to()
 
 ; CHECK: llvm.module_flags [#llvm.mlir.module_flag<append, "CG Profile", [
 ; CHECK-SAME: #llvm.cgprofile_entry<from = @from, to = @to, count = 222>,
-; CHECK-SAME: #llvm.cgprofile_entry<from = @from, to = null, count = 222>,
+; CHECK-SAME: #llvm.cgprofile_entry<from = @from, count = 222>,
 ; CHECK-SAME: #llvm.cgprofile_entry<from = @to, to = @from, count = 222>
 ; CHECK-SAME: ]>]

mlir/test/Target/LLVMIR/llvmir.mlir

@@ -2840,7 +2840,7 @@ module {
 
 llvm.module_flags [#llvm.mlir.module_flag<append, "CG Profile", [
   #llvm.cgprofile_entry<from = @from, to = @to, count = 222>,
-  #llvm.cgprofile_entry<from = @from, to = null, count = 222>,
+  #llvm.cgprofile_entry<from = @from, count = 222>,
   #llvm.cgprofile_entry<from = @to, to = @from, count = 222>
 ]>]
 llvm.func @from(i32)