[flang][hlfir] Separate -emit-fir and -emit-hlfir for flang-new

In review for https://reviews.llvm.org/D146278, @vzakhari asked to separate -emit-fir and -emit-hlfir. This will allow FIR to be easily outputted after the HLFIR passes have been run. The new semantics are as follows: | Action | -flang-experimental-hlfir? | Result | | =========== | ========================== | =============================== | | -emit-hlfir | N | Outputs HLFIR | | -emit-hlfir | Y | Outputs HLFIR | | -emit-fir | N | Outputs FIR, using old lowering | | -emit-fir | Y | Outputs FIR, lowering via HLFIR | A patch for bbc will follow. Differential Revision: https://reviews.llvm.org/D151088
llvm · Jun 1, 2023 · 39ecf9d · 39ecf9d
1 parent 01ef213
commit 39ecf9d
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Showing 8 changed files with 110 additions and 29 deletions.
diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
@@ -5268,9 +5268,12 @@ def fno_reformat : Flag<["-"], "fno-reformat">, Group<Preprocessor_Group>,
   HelpText<"Dump the cooked character stream in -E mode">;
 defm analyzed_objects_for_unparse : OptOutFC1FFlag<"analyzed-objects-for-unparse", "", "Do not use the analyzed objects when unparsing">;
 
-def emit_mlir : Flag<["-"], "emit-mlir">, Group<Action_Group>,
-  HelpText<"Build the parse tree, then lower it to MLIR">;
-def emit_fir : Flag<["-"], "emit-fir">, Alias<emit_mlir>;
+def emit_fir : Flag<["-"], "emit-fir">, Group<Action_Group>,
+  HelpText<"Build the parse tree, then lower it to FIR">;
+def emit_mlir : Flag<["-"], "emit-mlir">, Alias<emit_fir>;
+
+def emit_hlfir : Flag<["-"], "emit-hlfir">, Group<Action_Group>,
+  HelpText<"Build the parse tree, then lower it to HLFIR">;
 
 } // let Flags = [FC1Option, FlangOnlyOption]
 

diff --git a/flang/include/flang/Frontend/FrontendActions.h b/flang/include/flang/Frontend/FrontendActions.h
@@ -191,7 +191,8 @@ enum class BackendActionTy {
   Backend_EmitObj,      ///< Emit native object files
   Backend_EmitBC,       ///< Emit LLVM bitcode files
   Backend_EmitLL,       ///< Emit human-readable LLVM assembly
-  Backend_EmitMLIR      ///< Emit MLIR files
+  Backend_EmitFIR,      ///< Emit FIR files, possibly lowering via HLFIR
+  Backend_EmitHLFIR,    ///< Emit HLFIR files before any passes run
 };
 
 /// Abstract base class for actions that generate code (MLIR, LLVM IR, assembly
@@ -224,6 +225,9 @@ class CodeGenAction : public FrontendAction {
   /// Embeds offload objects given with specified with -fembed-offload-object
   void embedOffloadObjects();
 
+  /// Runs pass pipeline to lower HLFIR into FIR
+  void lowerHLFIRToFIR();
+
   /// Generates an LLVM IR module from CodeGenAction::mlirModule and saves it
   /// in CodeGenAction::llvmModule.
   void generateLLVMIR();
@@ -236,9 +240,14 @@ class CodeGenAction : public FrontendAction {
   ~CodeGenAction() override;
 };
 
-class EmitMLIRAction : public CodeGenAction {
+class EmitFIRAction : public CodeGenAction {
+public:
+  EmitFIRAction() : CodeGenAction(BackendActionTy::Backend_EmitFIR) {}
+};
+
+class EmitHLFIRAction : public CodeGenAction {
 public:
-  EmitMLIRAction() : CodeGenAction(BackendActionTy::Backend_EmitMLIR) {}
+  EmitHLFIRAction() : CodeGenAction(BackendActionTy::Backend_EmitHLFIR) {}
 };
 
 class EmitLLVMAction : public CodeGenAction {

diff --git a/flang/include/flang/Frontend/FrontendOptions.h b/flang/include/flang/Frontend/FrontendOptions.h
@@ -34,8 +34,11 @@ enum ActionKind {
   /// -fsyntax-only
   ParseSyntaxOnly,
 
-  /// Emit a .mlir file
-  EmitMLIR,
+  /// Emit FIR mlir file
+  EmitFIR,
+
+  /// Emit HLFIR mlir file
+  EmitHLFIR,
 
   /// Emit an .ll file
   EmitLLVM,

diff --git a/flang/lib/Frontend/CompilerInvocation.cpp b/flang/lib/Frontend/CompilerInvocation.cpp
@@ -306,8 +306,11 @@ static bool parseFrontendArgs(FrontendOptions &opts, llvm::opt::ArgList &args,
     case clang::driver::options::OPT_fsyntax_only:
       opts.programAction = ParseSyntaxOnly;
       break;
-    case clang::driver::options::OPT_emit_mlir:
-      opts.programAction = EmitMLIR;
+    case clang::driver::options::OPT_emit_fir:
+      opts.programAction = EmitFIR;
+      break;
+    case clang::driver::options::OPT_emit_hlfir:
+      opts.programAction = EmitHLFIR;
       break;
     case clang::driver::options::OPT_emit_llvm:
       opts.programAction = EmitLLVM;
@@ -911,7 +914,8 @@ bool CompilerInvocation::createFromArgs(
   }
 
   // -flang-experimental-hlfir
-  if (args.hasArg(clang::driver::options::OPT_flang_experimental_hlfir)) {
+  if (args.hasArg(clang::driver::options::OPT_flang_experimental_hlfir) ||
+      args.hasArg(clang::driver::options::OPT_emit_hlfir)) {
     res.loweringOpts.setLowerToHighLevelFIR(true);
   }
 

diff --git a/flang/lib/Frontend/FrontendActions.cpp b/flang/lib/Frontend/FrontendActions.cpp
@@ -647,6 +647,34 @@ mapToLevel(const Fortran::frontend::CodeGenOptions &opts) {
   }
 }
 
+// Lower using HLFIR then run the FIR to HLFIR pipeline
+void CodeGenAction::lowerHLFIRToFIR() {
+  assert(mlirModule && "The MLIR module has not been generated yet.");
+
+  CompilerInstance &ci = this->getInstance();
+  auto opts = ci.getInvocation().getCodeGenOpts();
+  llvm::OptimizationLevel level = mapToLevel(opts);
+
+  fir::support::loadDialects(*mlirCtx);
+
+  // Set-up the MLIR pass manager
+  mlir::PassManager pm((*mlirModule)->getName(),
+                       mlir::OpPassManager::Nesting::Implicit);
+
+  pm.addPass(std::make_unique<Fortran::lower::VerifierPass>());
+  pm.enableVerifier(/*verifyPasses=*/true);
+
+  // Create the pass pipeline
+  fir::createHLFIRToFIRPassPipeline(pm, level);
+  (void)mlir::applyPassManagerCLOptions(pm);
+
+  if (!mlir::succeeded(pm.run(*mlirModule))) {
+    unsigned diagID = ci.getDiagnostics().getCustomDiagID(
+        clang::DiagnosticsEngine::Error, "Lowering to FIR failed");
+    ci.getDiagnostics().Report(diagID);
+  }
+}
+
 // Lower the previously generated MLIR module into an LLVM IR module
 void CodeGenAction::generateLLVMIR() {
   assert(mlirModule && "The MLIR module has not been generated yet.");
@@ -751,7 +779,9 @@ getOutputStream(CompilerInstance &ci, llvm::StringRef inFile,
   case BackendActionTy::Backend_EmitLL:
     return ci.createDefaultOutputFile(
         /*Binary=*/false, inFile, /*extension=*/"ll");
-  case BackendActionTy::Backend_EmitMLIR:
+  case BackendActionTy::Backend_EmitFIR:
+    LLVM_FALLTHROUGH;
+  case BackendActionTy::Backend_EmitHLFIR:
     return ci.createDefaultOutputFile(
         /*Binary=*/false, inFile, /*extension=*/"mlir");
   case BackendActionTy::Backend_EmitBC:
@@ -914,7 +944,17 @@ void CodeGenAction::executeAction() {
     }
   }
 
-  if (action == BackendActionTy::Backend_EmitMLIR) {
+  if (action == BackendActionTy::Backend_EmitFIR) {
+    if (ci.getInvocation().getLoweringOpts().getLowerToHighLevelFIR()) {
+      lowerHLFIRToFIR();
+    }
+    mlirModule->print(ci.isOutputStreamNull() ? *os : ci.getOutputStream());
+    return;
+  }
+
+  if (action == BackendActionTy::Backend_EmitHLFIR) {
+    assert(ci.getInvocation().getLoweringOpts().getLowerToHighLevelFIR() &&
+           "Lowering must have been configured to emit HLFIR");
     mlirModule->print(ci.isOutputStreamNull() ? *os : ci.getOutputStream());
     return;
   }

diff --git a/flang/lib/FrontendTool/ExecuteCompilerInvocation.cpp b/flang/lib/FrontendTool/ExecuteCompilerInvocation.cpp
@@ -40,8 +40,10 @@ createFrontendAction(CompilerInstance &ci) {
     return std::make_unique<PrintPreprocessedAction>();
   case ParseSyntaxOnly:
     return std::make_unique<ParseSyntaxOnlyAction>();
-  case EmitMLIR:
-    return std::make_unique<EmitMLIRAction>();
+  case EmitFIR:
+    return std::make_unique<EmitFIRAction>();
+  case EmitHLFIR:
+    return std::make_unique<EmitHLFIRAction>();
   case EmitLLVM:
     return std::make_unique<EmitLLVMAction>();
   case EmitLLVMBitcode:

diff --git a/flang/test/Driver/driver-help.f90 b/flang/test/Driver/driver-help.f90
@@ -94,9 +94,10 @@
 ! HELP-FC1-NEXT:OPTIONS:
 ! HELP-FC1-NEXT: -cpp                   Enable predefined and command line preprocessor macros
 ! HELP-FC1-NEXT: -D <macro>=<value>     Define <macro> to <value> (or 1 if <value> omitted)
+! HELP-FC1-NEXT: -emit-fir              Build the parse tree, then lower it to FIR
+! HELP-FC1-NEXT: -emit-hlfir            Build the parse tree, then lower it to HLFIR
 ! HELP-FC1-NEXT: -emit-llvm-bc          Build ASTs then convert to LLVM, emit .bc file
 ! HELP-FC1-NEXT: -emit-llvm Use the LLVM representation for assembler and object files
-! HELP-FC1-NEXT: -emit-mlir Build the parse tree, then lower it to MLIR
 ! HELP-FC1-NEXT: -emit-obj Emit native object files
 ! HELP-FC1-NEXT: -E                     Only run the preprocessor
 ! HELP-FC1-NEXT: -falternative-parameter-statement

diff --git a/flang/test/HLFIR/flang-experimental-hlfir-flag.f90 b/flang/test/HLFIR/flang-experimental-hlfir-flag.f90
@@ -1,19 +1,38 @@
-! Test -flang-experimental-hlfir flag
-! RUN: %flang_fc1 -flang-experimental-hlfir -emit-fir -o - %s | FileCheck %s
-! RUN: %flang_fc1 -emit-fir -o - %s | FileCheck %s --check-prefix NO-HLFIR
+! Test -flang-experimental-hlfir, -emit-hlfir, -emit-fir flags
+! RUN: %flang_fc1 -emit-hlfir -o - %s | FileCheck --check-prefix HLFIR --check-prefix ALL %s
+! RUN: %flang_fc1 -emit-hlfir -flang-experimental-hlfir -o - %s | FileCheck --check-prefix HLFIR --check-prefix ALL %s
+! RUN: %flang_fc1 -emit-fir -o - %s | FileCheck %s --check-prefix NO-HLFIR --check-prefix ALL
+! RUN: %flang_fc1 -emit-fir -flang-experimental-hlfir -o - %s | FileCheck --check-prefix FIR --check-prefix ALL %s
+
+! | Action      | -flang-experimental-hlfir? | Result                          |
+! | =========== | ========================== | =============================== |
+! | -emit-hlfir | N                          | Outputs HLFIR                   |
+! | -emit-hlfir | Y                          | Outputs HLFIR                   |
+! | -emit-fir   | N                          | Outputs FIR, using old lowering |
+! | -emit-fir   | Y                          | Outputs FIR, lowering via HLFIR |
 
 subroutine test(a, res)
   real :: a(:), res
   res = SUM(a)
 end subroutine
-! CHECK-LABEL: func.func @_QPtest
-! CHECK:           %[[A:.*]]: !fir.box<!fir.array<?xf32>>
-! CHECK:           %[[RES:.*]]: !fir.ref<f32>
-! CHECK-DAG:     %[[A_VAR:.*]]:2 = hlfir.declare %[[A]]
-! CHECK-DAG:     %[[RES_VAR:.*]]:2 = hlfir.declare %[[RES]]
-! CHECK-NEXT:    %[[SUM_RES:.*]] = hlfir.sum %[[A_VAR]]#0
-! CHECK-NEXT:    hlfir.assign %[[SUM_RES]] to %[[RES_VAR]]#0
-! CHECK-NEXT:    return
-! CHECK-NEXT:  }
+! ALL-LABEL: func.func @_QPtest
+! ALL:             %[[A:.*]]: !fir.box<!fir.array<?xf32>>
+! ALL:             %[[RES:.*]]: !fir.ref<f32>
+
+! HLFIR:         %[[A_VAR:.*]]:2 = hlfir.declare %[[A]]
+! fir.declare is only generated via the hlfir -> fir lowering
+! FIR:           %[[A_VAR:.*]] = fir.declare %[[A]]
+! NO-HLFIR-NOT:  fir.declare
+
+! HLFIR-DAG:     %[[RES_VAR:.*]]:2 = hlfir.declare %[[RES]]
+! FIR:           %[[RES_VAR:.*]] = fir.declare %[[RES]]
+! NO-HLFIR-NOT:  fir.declare
+
+! HLFIR-NEXT:    %[[SUM_RES:.*]] = hlfir.sum %[[A_VAR]]#0
+! HLFIR-NEXT:    hlfir.assign %[[SUM_RES]] to %[[RES_VAR]]#0
+! FIR-NOT:       hlfir.
+! NO-HLFIR-NOT:  hlfir.
+
+! ALL:           return
+! ALL-NEXT:  }
 
-! NO-HLFIR-NOT: hlfir.