Remove stubs entirely

Makefile

@@ -1333,10 +1333,6 @@ GENERATOR_AOTCPP_TESTS := $(filter-out generator_aotcpp_msan,$(GENERATOR_AOTCPP_
 # https://github.com/halide/Halide/issues/7272
 GENERATOR_AOTCPP_TESTS := $(filter-out generator_aotcpp_memory_profiler_mandelbrot,$(GENERATOR_AOTCPP_TESTS))
 
-# https://github.com/halide/Halide/issues/4916
-GENERATOR_AOTCPP_TESTS := $(filter-out generator_aotcpp_stubtest,$(GENERATOR_AOTCPP_TESTS))
-GENERATOR_AOTCPP_TESTS := $(filter-out generator_aotcpp_stubuser,$(GENERATOR_AOTCPP_TESTS))
-
 # Build requirements are finicky, testing non-C++ backend is good enough here
 GENERATOR_AOTCPP_TESTS := $(filter-out generator_aotcpp_gpu_multi_context_threaded,$(GENERATOR_AOTCPP_TESTS))
 
@@ -1549,10 +1545,6 @@ $(FILTERS_DIR)/%.halide_generated.cpp: $(FILTERS_DIR)/%.a
 $(FILTERS_DIR)/%.registration.cpp: $(FILTERS_DIR)/%.a
 	@echo $@ produced implicitly by $^
 
-$(FILTERS_DIR)/%.stub.h: $(BIN_DIR)/%.generator
-	@mkdir -p $(@D)
-	$(CURDIR)/$< -g $* -n $* -o $(CURDIR)/$(FILTERS_DIR) -e cpp_stub
-
 $(FILTERS_DIR)/cxx_mangling_externs.o: $(ROOT_DIR)/test/generator/cxx_mangling_externs.cpp
 	@mkdir -p $(@D)
 	$(CXX) $(GEN_AOT_CXX_FLAGS) -c $(filter-out %.h,$^) $(GEN_AOT_INCLUDES) -o $@
@@ -1714,28 +1706,6 @@ endif
 $(BIN_DIR)/$(TARGET)/generator_aotcpp_cxx_mangling: $(FILTERS_DIR)/cxx_mangling_externs.o
 $(BIN_DIR)/$(TARGET)/generator_aotcpp_cxx_mangling_define_extern: $(FILTERS_DIR)/cxx_mangling.halide_generated.cpp $(FILTERS_DIR)/cxx_mangling_externs.o $(FILTERS_DIR)/cxx_mangling_define_extern_externs.o
 
-$(BUILD_DIR)/stubuser_generator.o: $(FILTERS_DIR)/stubtest.stub.h $(FILTERS_DIR)/configure.stub.h
-$(BIN_DIR)/stubuser.generator: $(BUILD_DIR)/stubtest_generator.o $(BUILD_DIR)/configure_generator.o
-
-# stubtest has input and output funcs with undefined types and array sizes; this is fine for stub
-# usage (the types can be inferred), but for AOT compilation, we must make the types
-# concrete via generator args.
-STUBTEST_GENERATOR_ARGS=\
-	untyped_buffer_input.type=uint8 untyped_buffer_input.dim=3 \
-	simple_input.type=float32 \
-	array_input.type=float32 array_input.size=2 \
-	int_arg.size=2 \
-	tuple_output.type=float32,float32 \
-	vectorize=true
-
-$(FILTERS_DIR)/stubtest.a: $(BIN_DIR)/stubtest.generator
-	@mkdir -p $(@D)
-	$(CURDIR)/$< -g stubtest -f stubtest $(GEN_AOT_OUTPUTS) -o $(CURDIR)/$(FILTERS_DIR) target=$(TARGET)-no_runtime $(STUBTEST_GENERATOR_ARGS)
-
-$(FILTERS_DIR)/stubuser_auto.a: $(BIN_DIR)/stubuser.generator $(BIN_MULLAPUDI2016)
-	@mkdir -p $(@D)
-	$(CURDIR)/$< -g stubuser $(GEN_AOT_OUTPUTS) -o $(CURDIR)/$(FILTERS_DIR) -f stubuser_auto target=$(TARGET)-no_runtime autoscheduler=Mullapudi2016 -p $(BIN_MULLAPUDI2016)
-
 $(FILTERS_DIR)/autograd_grad.a: $(BIN_DIR)/autograd.generator $(BIN_MULLAPUDI2016)
 	@mkdir -p $(@D)
 	$(CURDIR)/$< -g autograd $(GEN_AOT_OUTPUTS) -o $(CURDIR)/$(FILTERS_DIR) -f autograd_grad target=$(TARGET)-no_runtime autoscheduler=Mullapudi2016 -d 1 -p $(BIN_MULLAPUDI2016)
@@ -1841,16 +1811,11 @@ $(BIN_DIR)/$(TARGET)/generator_aotcpp_define_extern_opencl: $(ROOT_DIR)/test/gen
 	@mkdir -p $(@D)
 	$(CXX) $(GEN_AOT_CXX_FLAGS) $(filter %.cpp %.o %.a,$^) $(GEN_AOT_INCLUDES) $(GEN_AOT_LD_FLAGS) $(OPENCL_LD_FLAGS) -o $@
 
-# By default, %_jittest.cpp depends on libHalide, plus the stubs for the Generator. These are external tests that use the JIT.
-$(BIN_DIR)/generator_jit_%: $(ROOT_DIR)/test/generator/%_jittest.cpp $(TEST_DEPS) $(FILTERS_DIR)/%.stub.h $(BUILD_DIR)/%_generator.o
+# By default, %_jittest.cpp depends on libHalide. These are external tests that use the JIT.
+$(BIN_DIR)/generator_jit_%: $(ROOT_DIR)/test/generator/%_jittest.cpp $(TEST_DEPS) $(BUILD_DIR)/%_generator.o
 	@mkdir -p $(@D)
 	$(CXX) -g $(TEST_CXX_FLAGS) $(filter %.cpp %.o %.a,$^) -I$(INCLUDE_DIR) -I$(FILTERS_DIR) -I $(ROOT_DIR)/apps/support $(TEST_LD_FLAGS) -o $@
 
-# stubuser is run with autoscheduling too
-$(BIN_DIR)/$(TARGET)/generator_aot_stubuser: $(ROOT_DIR)/test/generator/stubuser_aottest.cpp $(FILTERS_DIR)/stubuser.a $(FILTERS_DIR)/stubuser.h $(FILTERS_DIR)/stubuser_auto.a $(FILTERS_DIR)/stubuser_auto.h $(RUNTIME_EXPORTED_INCLUDES) $(BIN_DIR)/$(TARGET)/runtime.a
-	@mkdir -p $(@D)
-	$(CXX) $(GEN_AOT_CXX_FLAGS) $(filter %.cpp %.o %.a,$^) $(GEN_AOT_INCLUDES) $(GEN_AOT_LD_FLAGS) -o $@
-
 # generator_aot_multitarget is run multiple times, with different env vars.
 generator_aot_multitarget: $(BIN_DIR)/$(TARGET)/generator_aot_multitarget
 	@mkdir -p $(@D)

apps/CMakeLists.txt

@@ -56,7 +56,6 @@ add_app(iir_blur)
 add_app(interpolate)
 add_app(lens_blur)
 add_app(linear_algebra)
-# add_app(linear_blur)  # TODO(#5374): missing CMake build
 add_app(local_laplacian)
 add_app(max_filter)
 add_app(nl_means)

cmake/HalideGeneratorHelpers.cmake

@@ -182,7 +182,6 @@ function(_Halide_library_from_generator TARGET)
     set(compiler_log_extension ".halide_compiler_log")
     set(conceptual_stmt_extension ".conceptual.stmt")
     set(conceptual_stmt_html_extension ".conceptual.stmt.html")
-    # set(cpp_stub_extension ".stub.h")  # not implemented
     set(device_code_extension ".device_code")
     set(featurization_extension ".featurization")
     set(function_info_header_extension ".function_info.h")
@@ -450,7 +449,6 @@ function(add_halide_library TARGET)
 
     # See Module.cpp for list of extra outputs. The following outputs intentionally do not appear:
     # - `c_header` is always generated
-    # - `cpp_stub` is not available
     # - `object` is selected for CMake-target-compile
     # - `static_library` is selected for cross-compile
     set(extra_output_names

python_bindings/src/halide/halide_/PyEnums.cpp

@@ -230,7 +230,6 @@ void define_enums(py::module &m) {
         .value("c_header", OutputFileType::c_header)
         .value("c_source", OutputFileType::c_source)
         .value("compiler_log", OutputFileType::compiler_log)
-        .value("cpp_stub", OutputFileType::cpp_stub)
         .value("featurization", OutputFileType::featurization)
         .value("function_info_header", OutputFileType::function_info_header)
         .value("hlpipe", OutputFileType::hlpipe)

python_bindings/src/halide/halide_/PyGenerator.cpp

@@ -87,12 +87,6 @@ class PyGeneratorBase : public AbstractGenerator {
         generator_.attr("_bind_input")(v);
     }
 
-    bool emit_cpp_stub(const std::string & /*stub_file_path*/) override {
-        // Python Generators don't support this (and *never* will, so don't ask),
-        // but don't throw an error, just return false.
-        return false;
-    }
-
     bool emit_hlpipe(const std::string & /*hlpipe_file_path*/) override {
         // Python Generators don't support this yet ...
         // but don't throw an error, just return false.

python_bindings/stub/PyStubImpl.cpp

@@ -25,8 +25,6 @@ namespace PythonBindings {
 using ArgInfoKind = Internal::ArgInfoKind;
 using ArgInfo = Internal::AbstractGenerator::ArgInfo;
 using GeneratorFactory = Internal::GeneratorFactory;
-using StubInput = Internal::StubInput;
-using StubInputBuffer = Internal::StubInputBuffer<void>;
 
 namespace {
 

src/AbstractGenerator.h

@@ -162,21 +162,6 @@ class AbstractGenerator {
     virtual void bind_input(const std::string &name, const std::vector<Expr> &v) = 0;
     // @}
 
-    /** Emit a Generator Stub (.stub.h) file to the given path. Not all Generators support this.
-     *
-     * If you call this method, you should not call any other AbstractGenerator methods
-     * on this instance, before or after this call.
-     *
-     * If the Generator is capable of emitting a Stub, do so and return true. (Errors
-     * during stub emission should assert-fail rather than returning false.)
-     *
-     * If the Generator is not capable of emitting a Stub, do nothing and return false.
-     *
-     * CALL-AFTER: none
-     * CALL-BEFORE: none
-     */
-    virtual bool emit_cpp_stub(const std::string &stub_file_path) = 0;
-
     /** Emit a Serialized Halide Pipeline (.hlpipe) file to the given path. Not all Generators support this.
      *
      * If you call this method, you should not call any other AbstractGenerator methods