Remove Introspection (#8273)

* Remove Introspection

Introspection (to provide better error messages + automatic var/func/etc names) has always been kinda handy but kinda fragile, and with the evolution of the DWARF standard it's become broken for newer compilers. We don't have the bandwidth to fix it, and many large customers (e.g. Google) have never been able to rely on it, and given that it can cause crashes in some unusual situations (e.g. when embedded inside a Go app), it's time to say goodbye.

Alas! Poor Introspection. I knew him, Horatio. A feature of infinite jest, of most excellent fancy. It hath borne me on his back a thousand times.

* Update Deserialization.cpp

---------

Co-authored-by: Andrew Adams <andrew.b.adams@gmail.com>

Makefile

@@ -130,7 +130,6 @@ WITH_D3D12 ?= not-empty
 WITH_VULKAN ?= not-empty
 WITH_SPIRV ?= not-empty
 WITH_WEBGPU ?= not-empty
-WITH_INTROSPECTION ?= not-empty
 WITH_EXCEPTIONS ?=
 WITH_LLVM_INSIDE_SHARED_LIBHALIDE ?= not-empty
 
@@ -173,7 +172,6 @@ AARCH64_LLVM_CONFIG_LIB=$(if $(WITH_AARCH64), aarch64, )
 RISCV_CXX_FLAGS=$(if $(WITH_RISCV), -DWITH_RISCV, )
 RISCV_LLVM_CONFIG_LIB=$(if $(WITH_RISCV), riscv, )
 
-INTROSPECTION_CXX_FLAGS=$(if $(WITH_INTROSPECTION), -DWITH_INTROSPECTION, )
 EXCEPTIONS_CXX_FLAGS=$(if $(WITH_EXCEPTIONS), -DHALIDE_WITH_EXCEPTIONS -fexceptions, )
 
 HEXAGON_CXX_FLAGS=$(if $(WITH_HEXAGON), -DWITH_HEXAGON, )
@@ -218,7 +216,6 @@ CXX_FLAGS += $(METAL_CXX_FLAGS)
 CXX_FLAGS += $(D3D12_CXX_FLAGS)
 CXX_FLAGS += $(WEBGPU_CXX_FLAGS)
 CXX_FLAGS += $(POWERPC_CXX_FLAGS)
-CXX_FLAGS += $(INTROSPECTION_CXX_FLAGS)
 CXX_FLAGS += $(EXCEPTIONS_CXX_FLAGS)
 CXX_FLAGS += $(AMDGPU_CXX_FLAGS)
 CXX_FLAGS += $(RISCV_CXX_FLAGS)
@@ -512,7 +509,6 @@ SOURCE_FILES = \
   InlineReductions.cpp \
   IntegerDivisionTable.cpp \
   Interval.cpp \
-  Introspection.cpp \
   IR.cpp \
   IREquality.cpp \
   IRMatch.cpp \
@@ -712,7 +708,6 @@ HEADER_FILES = \
   InlineReductions.h \
   IntegerDivisionTable.h \
   Interval.h \
-  Introspection.h \
   IntrusivePtr.h \
   IR.h \
   IREquality.h \

python_bindings/src/halide/halide_/PyScheduleMethods.h

@@ -107,9 +107,7 @@ HALIDE_NEVER_INLINE void add_schedule_methods(PythonClass &class_instance) {
                 // Templated function; specializing only on ImageParam for now
                 return t.template prefetch<ImageParam>(image, at, from, offset, strategy);
             },
-            py::arg("image"), py::arg("at"), py::arg("from"), py::arg("offset") = 1, py::arg("strategy") = PrefetchBoundStrategy::GuardWithIf)
-
-        .def("source_location", &T::source_location);
+            py::arg("image"), py::arg("at"), py::arg("from"), py::arg("offset") = 1, py::arg("strategy") = PrefetchBoundStrategy::GuardWithIf);
 }
 
 }  // namespace PythonBindings

src/Buffer.h

@@ -196,7 +196,7 @@ class Buffer {
         : contents(new Internal::BufferContents) {
         contents->buf = std::move(buf);
         if (name.empty()) {
-            contents->name = Internal::make_entity_name(this, "Halide:.*:Buffer<.*>", 'b');
+            contents->name = Internal::unique_name('b');
         } else {
             contents->name = name;
         }

src/CMakeLists.txt

@@ -91,7 +91,6 @@ set(HEADER_FILES
     InlineReductions.h
     IntegerDivisionTable.h
     Interval.h
-    Introspection.h
     IntrusivePtr.h
     IR.h
     IREquality.h
@@ -262,7 +261,6 @@ set(SOURCE_FILES
     InlineReductions.cpp
     IntegerDivisionTable.cpp
     Interval.cpp
-    Introspection.cpp
     IR.cpp
     IREquality.cpp
     IRMatch.cpp
@@ -563,11 +561,6 @@ target_compile_definitions(Halide PUBLIC
 target_include_directories(Halide INTERFACE "$<BUILD_INTERFACE:${Halide_BINARY_DIR}/include>")
 add_dependencies(Halide HalideIncludes)
 
-option(Halide_WITH_INTROSPECTION "Enable use of debugging symbols for default Func, Var, etc. names" ON)
-if (Halide_WITH_INTROSPECTION)
-    target_compile_definitions(Halide PRIVATE WITH_INTROSPECTION)
-endif ()
-
 if (TARGET Halide_wabt)
     target_link_libraries(Halide PRIVATE Halide_wabt)
     target_compile_definitions(Halide PRIVATE WITH_WABT)

src/Definition.cpp

@@ -6,7 +6,6 @@
 #include "IR.h"
 #include "IRMutator.h"
 #include "IROperator.h"
-#include "Introspection.h"
 #include "Var.h"
 
 namespace Halide {
@@ -22,7 +21,6 @@ struct DefinitionContents {
     std::vector<Expr> values, args;
     StageSchedule stage_schedule;
     std::vector<Specialization> specializations;
-    std::string source_location;
 
     DefinitionContents()
         : predicate(const_true()) {
@@ -99,7 +97,6 @@ Definition::Definition(const std::vector<Expr> &args, const std::vector<Expr> &v
     contents->is_init = is_init;
     contents->values = values;
     contents->args = args;
-    contents->source_location = Introspection::get_source_location();
     if (rdom.defined()) {
         contents->predicate = rdom.predicate();
         for (const auto &rv : rdom.domain()) {
@@ -109,15 +106,14 @@ Definition::Definition(const std::vector<Expr> &args, const std::vector<Expr> &v
 }
 
 Definition::Definition(bool is_init, const Expr &predicate, const std::vector<Expr> &args, const std::vector<Expr> &values,
-                       const StageSchedule &schedule, const std::vector<Specialization> &specializations, const std::string &source_location)
+                       const StageSchedule &schedule, const std::vector<Specialization> &specializations)
     : contents(new DefinitionContents) {
     contents->is_init = is_init;
     contents->values = values;
     contents->args = args;
     contents->predicate = predicate;
     contents->stage_schedule = schedule;
     contents->specializations = specializations;
-    contents->source_location = source_location;
 }
 
 Definition Definition::get_copy() const {
@@ -129,7 +125,6 @@ Definition Definition::get_copy() const {
     copy.contents->values = contents->values;
     copy.contents->args = contents->args;
     copy.contents->stage_schedule = contents->stage_schedule.get_copy();
-    copy.contents->source_location = contents->source_location;
 
     // Deep-copy specializations
     for (const Specialization &s : contents->specializations) {
@@ -204,10 +199,6 @@ const std::vector<Specialization> &Definition::specializations() const {
     return contents->specializations;
 }
 
-std::string Definition::source_location() const {
-    return contents->source_location;
-}
-
 const Specialization &Definition::add_specialization(Expr condition) {
     Specialization s;
     s.condition = std::move(condition);
@@ -216,7 +207,6 @@ const Specialization &Definition::add_specialization(Expr condition) {
     s.definition.contents->predicate = contents->predicate;
     s.definition.contents->values = contents->values;
     s.definition.contents->args = contents->args;
-    s.definition.contents->source_location = contents->source_location;
 
     // The sub-schedule inherits everything about its parent except for its specializations.
     s.definition.contents->stage_schedule = contents->stage_schedule.get_copy();

src/Definition.h

@@ -49,7 +49,7 @@ class Definition {
 
     /** Construct a Definition with deserialized data. */
     Definition(bool is_init, const Expr &predicate, const std::vector<Expr> &args, const std::vector<Expr> &values,
-               const StageSchedule &schedule, const std::vector<Specialization> &specializations, const std::string &source_location);
+               const StageSchedule &schedule, const std::vector<Specialization> &specializations);
 
     /** Construct an undefined Definition object. */
     Definition();
@@ -123,12 +123,6 @@ class Definition {
     std::vector<Specialization> &specializations();
     const Specialization &add_specialization(Expr condition);
     // @}
-
-    /** Attempt to get the source file and line where this definition
-     * was made using DWARF introspection. Returns an empty string if
-     * no debug symbols were found or the debug symbols were not
-     * understood. Works on OS X and Linux only. */
-    std::string source_location() const;
 };
 
 struct Specialization {

src/Deserialization.cpp

@@ -1057,8 +1057,9 @@ Definition Deserializer::deserialize_definition(const Serialize::Definition *def
     const std::vector<Specialization> specializations =
         deserialize_vector<Serialize::Specialization, Specialization>(definition->specializations(),
                                                                       &Deserializer::deserialize_specialization);
+    // Deserialize and ignore this value.
     const auto source_location = deserialize_string(definition->source_location());
-    return Definition(is_init, predicate, args, values, stage_schedule, specializations, source_location);
+    return Definition(is_init, predicate, args, values, stage_schedule, specializations);
 }
 
 ReductionVariable Deserializer::deserialize_reduction_variable(const Serialize::ReductionVariable *reduction_variable) {

src/Error.cpp

@@ -1,5 +1,4 @@
 #include "Error.h"
-#include "Introspection.h"
 #include "Util.h"  // for get_env_variable
 
 #include <csignal>
@@ -155,7 +154,6 @@ ErrorReport::ErrorReport(const char *file, int line, const char *condition_strin
 #endif
     const char sep = use_newlines ? '\n' : ' ';
 
-    const std::string &source_loc = Introspection::get_source_location();
     const char *what = (flags & Warning) ? "Warning" : "Error";
     if (flags & User) {
         // Only mention where inside of libHalide the error tripped if we have debug level > 0
@@ -164,15 +162,9 @@ ErrorReport::ErrorReport(const char *file, int line, const char *condition_strin
             debug(1) << "Condition failed: " << condition_string << "\n";
         }
         msg << what << ":";
-        if (!source_loc.empty()) {
-            msg << " (at " << source_loc << ")";
-        }
         msg << sep;
     } else {
         msg << "Internal " << what << " at " << file << ":" << line;
-        if (source_loc.empty()) {
-            msg << " triggered by user code at " << source_loc << ":";
-        }
         msg << sep;
         if (condition_string) {
             msg << "Condition failed: " << condition_string << ":" << sep;

src/Func.cpp

@@ -69,11 +69,11 @@ Func::Func(const std::vector<Type> &required_types, int required_dims, const str
 }
 
 Func::Func()
-    : func(make_entity_name(this, "Halide:.*:Func", 'f')) {
+    : func(unique_name('f')) {
 }
 
 Func::Func(const Expr &e)
-    : func(make_entity_name(this, "Halide:.*:Func", 'f')) {
+    : func(unique_name('f')) {
     (*this)(_) = e;
 }
 
@@ -2146,14 +2146,6 @@ Stage &Stage::compute_with(const Stage &s, const VarOrRVar &var, LoopAlignStrate
     return compute_with(LoopLevel(s.function, var, s.stage_index), align);
 }
 
-/** Attempt to get the source file and line where this stage was
- * defined by parsing the process's own debug symbols. Returns an
- * empty string if no debug symbols were found or the debug
- * symbols were not understood. Works on OS X and Linux only. */
-std::string Stage::source_location() const {
-    return definition.source_location();
-}
-
 void Stage::unscheduled() {
     user_assert(!definition.schedule().touched()) << "Stage::unscheduled called on an update definition with a schedule\n";
     definition.schedule().touched() = true;
@@ -3492,11 +3484,6 @@ vector<Argument> Func::infer_arguments() const {
     return Pipeline(*this).infer_arguments();
 }
 
-std::string Func::source_location() const {
-    user_assert(defined()) << "A Func with no definition has no source_location\n";
-    return func.definition().source_location();
-}
-
 Module Func::compile_to_module(const vector<Argument> &args, const std::string &fn_name, const Target &target) {
     return pipeline().compile_to_module(args, fn_name, target);
 }

src/Func.h

@@ -471,12 +471,6 @@ class Stage {
     }
     // @}
 
-    /** Attempt to get the source file and line where this stage was
-     * defined by parsing the process's own debug symbols. Returns an
-     * empty string if no debug symbols were found or the debug
-     * symbols were not understood. Works on OS X and Linux only. */
-    std::string source_location() const;
-
     /** Assert that this stage has intentionally been given no schedule, and
      * suppress the warning about unscheduled update definitions that would
      * otherwise fire. This counts as a schedule, so calling this twice on the
@@ -2600,10 +2594,6 @@ class Func {
      */
     std::vector<Argument> infer_arguments() const;
 
-    /** Get the source location of the pure definition of this
-     * Func. See Stage::source_location() */
-    std::string source_location() const;
-
     /** Return the current StageSchedule associated with this initial
      * Stage of this Func. For introspection only: to modify schedule,
      * use the Func interface. */

src/Generator.cpp

@@ -1114,8 +1114,7 @@ void execute_generator(const ExecuteGeneratorArgs &args_in) {
 
 GeneratorParamBase::GeneratorParamBase(const std::string &name)
     : name_(name) {
-    ObjectInstanceRegistry::register_instance(this, 0, ObjectInstanceRegistry::GeneratorParam,
-                                              this, nullptr);
+    ObjectInstanceRegistry::register_instance(this, 0, ObjectInstanceRegistry::GeneratorParam, this);
 }
 
 GeneratorParamBase::~GeneratorParamBase() {
@@ -1238,9 +1237,9 @@ std::vector<std::string> GeneratorRegistry::enumerate() {
     return result;
 }
 
-GeneratorBase::GeneratorBase(size_t size, const void *introspection_helper)
+GeneratorBase::GeneratorBase(size_t size)
     : size(size) {
-    ObjectInstanceRegistry::register_instance(this, size, ObjectInstanceRegistry::Generator, this, introspection_helper);
+    ObjectInstanceRegistry::register_instance(this, size, ObjectInstanceRegistry::Generator, this);
 }
 
 GeneratorBase::~GeneratorBase() {
@@ -1851,7 +1850,7 @@ GeneratorInputBase::GeneratorInputBase(size_t array_size,
                                        const std::vector<Type> &t,
                                        int d)
     : GIOBase(array_size, name, kind, t, d) {
-    ObjectInstanceRegistry::register_instance(this, 0, ObjectInstanceRegistry::GeneratorInput, this, nullptr);
+    ObjectInstanceRegistry::register_instance(this, 0, ObjectInstanceRegistry::GeneratorInput, this);
 }
 
 GeneratorInputBase::GeneratorInputBase(const std::string &name, ArgInfoKind kind, const std::vector<Type> &t, int d)
@@ -1994,8 +1993,7 @@ void GeneratorInputBase::set_estimates_impl(const Region &estimates) {
 GeneratorOutputBase::GeneratorOutputBase(size_t array_size, const std::string &name, ArgInfoKind kind, const std::vector<Type> &t, int d)
     : GIOBase(array_size, name, kind, t, d) {
     internal_assert(kind != ArgInfoKind::Scalar);
-    ObjectInstanceRegistry::register_instance(this, 0, ObjectInstanceRegistry::GeneratorOutput,
-                                              this, nullptr);
+    ObjectInstanceRegistry::register_instance(this, 0, ObjectInstanceRegistry::GeneratorOutput, this);
 }
 
 GeneratorOutputBase::GeneratorOutputBase(const std::string &name, ArgInfoKind kind, const std::vector<Type> &t, int d)

src/Generator.h

@@ -274,7 +274,6 @@
 #include "AbstractGenerator.h"
 #include "Func.h"
 #include "ImageParam.h"
-#include "Introspection.h"
 #include "ObjectInstanceRegistry.h"
 #include "Target.h"
 
@@ -3359,7 +3358,7 @@ class GeneratorBase : public NamesInterface, public AbstractGenerator {
     }
 
 protected:
-    GeneratorBase(size_t size, const void *introspection_helper);
+    GeneratorBase(size_t size);
     void set_generator_names(const std::string &registered_name, const std::string &stub_name);
 
     // Note that it is explicitly legal to override init_from_context(), so that you can (say)
@@ -3741,8 +3740,7 @@ template<class T>
 class Generator : public Internal::GeneratorBase {
 protected:
     Generator()
-        : Internal::GeneratorBase(sizeof(T),
-                                  Internal::Introspection::get_introspection_helper<T>()) {
+        : Internal::GeneratorBase(sizeof(T)) {
     }
 
 public:

src/ImageParam.cpp

@@ -6,7 +6,7 @@ namespace Halide {
 
 ImageParam::ImageParam(Type t, int d)
     : OutputImageParam(
-          Parameter(t, true, d, Internal::make_entity_name(this, "Halide:.*:ImageParam", 'p')),
+          Parameter(t, true, d, Internal::unique_name('p')),
           Argument::InputBuffer,
           Func()) {
     // We must call create_func() after the super-ctor has completed.