[flang][fir] Add fir-opt tool

[clementval]

Summary

This patch introduce the fir-opt tool. Similar to mlir-opt for FIR.
It will be used in following patches to test fir opt and round-trip.

[clementval]

Add missing new line

[mehdi_amini]

Thanks, I wrote exactly this locally before seeing this patch! :)

Can you also update test/Fir/fir-ops.fir and test/Fir/fir-types.fir to use this? I had changed the run line this way:

// Parse operations and check that we can reparse what we print.
// RUN: fir-opt %s | fir-opt | FileCheck %s

flang/tools/fir-opt/CMakeLists.txt

22

This list of dependency should be pruned.

These two are obvious:

FIROptimizer
MLIROptLib

None of the others are.
I suspect the issue is that fir::registerFIRPasses() should not just be an inline function in a header but would better come in an implementation file, with a CMake target that pulls in the minimum number of dependencies to link the desired passes.
Otherwise any user of this function has to know the list of targets, and changing the function requires to change the build configuration of every user.

flang/tools/fir-opt/fir-opt.cpp

24

Can you replace the two lines above with fir::registerFIRDialects(registry); ?

26

(nit: missing newline)

[clementval]

In D96535#2557961, @mehdi_amini wrote:

Thanks, I wrote exactly this locally before seeing this patch! :)

Thanks for the review.

Sorry, I was a bit slow to submit the patch. When I saw your comment I suspect you might have started to work on it on your side as well.

flang/tools/fir-opt/CMakeLists.txt

22

I have pruned it to a minimum. I'll check with @schweitz so we refactor fir::registerFIRPasses().

[clementval]

Address review comment

[mehdi_amini]

flang/tools/fir-opt/CMakeLists.txt

22

LG, please separate ${dialect_libs} and MLIRAffineToStandard after a line TODO: these should be transitive dependencies from a target providing "registerFIRPasses()"

[mehdi_amini]

flang/test/Fir/fir-types.fir

2–3

Nit: types ;)

[clementval]

Address review comments

[clementval]

flang/test/Fir/fir-types.fir

2–3

My bad :)

[clementval]

Rebase

flang/test/CMakeLists.txt

configure_lit_site_cfg(
   MAIN_CONFIG
   ${CMAKE_CURRENT_SOURCE_DIR}/NonGtestUnit/lit.cfg.py
 )
 
 set(FLANG_TEST_PARAMS
   flang_site_config=${CMAKE_CURRENT_BINARY_DIR}/lit.site.cfg.py)
 
 set(FLANG_TEST_DEPENDS
-  f18 FileCheck count not module_files
+  f18 FileCheck count not module_files fir-opt
 )
 
 list(APPEND FLANG_TEST_DEPENDS tco)
 
 if (FLANG_BUILD_NEW_DRIVER)
   list(APPEND FLANG_TEST_DEPENDS flang-new)
 endif()
 

flang/test/Fir/fir-ops.fir

 // Test the FIR operations
-
-// RUN: tco -emit-fir %s | tco -emit-fir | FileCheck %s
+// Parse operations and check that we can reparse what we print.
+// RUN: fir-opt %s | fir-opt | FileCheck %s
 
 // CHECK-LABEL: func private @it1() -> !fir.int<4>
 // CHECK: func private @box1() -> !fir.boxchar<2>
 // CHECK: func private @box2() -> !fir.boxproc<(i32, i32) -> i64>
 // CHECK: func private @box3() -> !fir.box<!fir.type<derived3{f:f32}>>
 func private @it1() -> !fir.int<4>
 func private @box1() -> !fir.boxchar<2>
 func private @box2() -> !fir.boxproc<(i32, i32) -> i64>

flang/test/Fir/fir-types.fir

 // Test the FIR types
-
-// RUN: tco -emit-fir %s | tco -emit-fir | FileCheck %s
+// Parse types and check that we can reparse what we print.
+// RUN: fir-opt %s | fir-opt | FileCheck %s
 
 // Fortran Intrinsic types
 // CHECK-LABEL: func private @it1() -> !fir.int<4>
 // CHECK-LABEL: func private @it2() -> !fir.real<8>
 // CHECK-LABEL: func private @it3() -> !fir.complex<8>
 // CHECK-LABEL: func private @it4() -> !fir.logical<1>
 // CHECK-LABEL: func private @it5() -> !fir.char<1>
 // CHECK-LABEL: func private @it6() -> !fir.char<2,10>

flang/tools/CMakeLists.txt

 #===-- tools/CMakeLists.txt ------------------------------------------------===#
 #
 # Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 # See https://llvm.org/LICENSE.txt for license information.
 # SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 #
 #===------------------------------------------------------------------------===#
 
 add_subdirectory(f18)
 if(FLANG_BUILD_NEW_DRIVER)
   add_subdirectory(flang-driver)
 endif()
 add_subdirectory(tco)
 add_subdirectory(f18-parse-demo)
+add_subdirectory(fir-opt)

flang/tools/fir-opt/CMakeLists.txt

+add_flang_tool(fir-opt fir-opt.cpp)
+llvm_update_compile_flags(fir-opt)
+get_property(dialect_libs GLOBAL PROPERTY MLIR_DIALECT_LIBS)
+
+target_link_libraries(fir-opt PRIVATE
+  FIROptimizer
+  ${dialect_libs}
+
+  # TODO: these should be transitive dependencies from a target providing
+  # "registerFIRPasses()"
+  MLIRAffineToStandard
+  MLIROptLib
+)

flang/tools/fir-opt/fir-opt.cpp

+//===- fir-opt.cpp - FIR Optimizer Driver -----------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This is to be like LLVM's opt program, only for FIR.  Such a program is
+// required for roundtrip testing, etc.
+//
+//===----------------------------------------------------------------------===//
+
+#include "mlir/Support/MlirOptMain.h"
+#include "flang/Optimizer/Support/InitFIR.h"
+
+using namespace mlir;
+
+int main(int argc, char **argv) {
+  fir::support::registerFIRPasses();
+  DialectRegistry registry;
+  fir::support::registerDialects(registry);
+  return failed(MlirOptMain(argc, argv, "FIR modular optimizer driver\n",
+      registry, /*preloadDialectsInContext*/ false));
+}