1 files changed, 426 insertions, 0 deletions
diff --git a/backend/unittests/CodeGen/MachinePassManagerTest.cpp b/backend/unittests/CodeGen/MachinePassManagerTest.cpp
new file mode 100644
index 0000000..6e6c44d
--- /dev/null
+++ b/backend/unittests/CodeGen/MachinePassManagerTest.cpp
@@ -0,0 +1,426 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#include "rcc/CodeGen/MachinePassManager.h"
+
+#include "Target/TestTarget.h"
+#include "rcc/CodeGen/CompilationUnit.h"
+#include "rcc/CodeGen/GenericOpcodes.h"
+#include "rcc/CodeGen/MachineFunction.h"
+
+#include <atomic>
+#include <cstddef>
+#include <cstdint>
+#include <iostream>
+#include <memory>
+#include <string>
+#include <string_view>
+#include <utility>
+#include <vector>
+
+namespace {
+
+class TestContext final {
+public:
+  void expect(bool Condition, std::string_view Message) {
+    if (Condition)
+      return;
+    std::cerr << Message << '\n';
+    ++Failures;
+  }
+
+  [[nodiscard]] int result() const noexcept {
+    return Failures == 0 ? 0 : 1;
+  }
+
+private:
+  int Failures = 0;
+};
+
+[[nodiscard]] rcc::Expected<rcc::TargetDescription> createTarget() {
+  std::vector<rcc::InstructionDescriptor> Descriptors;
+  std::vector<rcc::ImmediatePredicate> Predicates;
+  auto Appended = rcc::appendGenericInstructionInfo(Descriptors, Predicates);
+  if (!Appended)
+    return std::unexpected(Appended.error());
+  auto Instructions = rcc::InstructionSet::create(std::move(Descriptors), std::move(Predicates));
+  if (!Instructions)
+    return std::unexpected(Instructions.error());
+  return rcc::test::createTestTargetDescription(std::move(*Instructions));
+}
+
+class BlockCountAnalysis final {
+public:
+  struct Result final {
+    std::size_t Count = 0;
+  };
+
+  [[nodiscard]] static constexpr std::string_view name() noexcept {
+    return "BlockCount";
+  }
+
+  [[nodiscard]] static rcc::Expected<Result> run(rcc::MachineFunction &Function,
+                                                 const rcc::TargetDescription &,
+                                                 rcc::MachineFunctionAnalysisManager &) {
+    return Result{Function.blockCount()};
+  }
+};
+
+class NonThreadSafeAnalysis final {
+public:
+  struct Result final {};
+
+  [[nodiscard]] static constexpr std::string_view name() noexcept {
+    return "NonThreadSafe";
+  }
+
+  [[nodiscard]] static rcc::Expected<Result> run(rcc::MachineFunction &,
+                                                 const rcc::TargetDescription &,
+                                                 rcc::MachineFunctionAnalysisManager &) {
+    return Result{};
+  }
+};
+
+class RequiredAnalysisPass final : public rcc::MachineFunctionPass {
+public:
+  [[nodiscard]] const rcc::MachinePassContract &contract() const noexcept override {
+    static const rcc::MachinePassContract Contract{
+        .Name = "RequiredAnalysis",
+        .Requires = {},
+        .Sets = {},
+        .Clears = {},
+        .RequiredAnalyses = {rcc::MachineFunctionAnalysisManager::id<BlockCountAnalysis>()},
+        .VerificationStage = std::nullopt,
+    };
+    return Contract;
+  }
+
+  [[nodiscard]] rcc::Expected<rcc::MachinePassResult>
+  run(rcc::MachineFunction &Function, const rcc::TargetDescription &Target,
+      rcc::MachineFunctionAnalysisManager &Analyses) override {
+    auto Blocks = Analyses.getResult<BlockCountAnalysis>(Function, Target);
+    if (!Blocks)
+      return std::unexpected(Blocks.error());
+    rcc::MachinePassResult Result;
+    Result.Preserved = rcc::PreservedAnalyses::all();
+    return Result;
+  }
+};
+
+class UnreportedChangePass final : public rcc::MachineFunctionPass {
+public:
+  [[nodiscard]] const rcc::MachinePassContract &contract() const noexcept override {
+    static const rcc::MachinePassContract Contract{
+        .Name = "UnreportedChange",
+        .Requires = {},
+        .Sets = {},
+        .Clears = {},
+        .RequiredAnalyses = {},
+        .VerificationStage = std::nullopt,
+    };
+    return Contract;
+  }
+
+  [[nodiscard]] rcc::Expected<rcc::MachinePassResult>
+  run(rcc::MachineFunction &Function, const rcc::TargetDescription &,
+      rcc::MachineFunctionAnalysisManager &) override {
+    auto Block = Function.createBasicBlock();
+    if (!Block)
+      return std::unexpected(Block.error());
+    auto Appended = Function.appendBlock(**Block);
+    if (!Appended)
+      return std::unexpected(Appended.error());
+    return rcc::MachinePassResult{};
+  }
+};
+
+class MutatingFailurePass final : public rcc::MachineFunctionPass {
+public:
+  [[nodiscard]] const rcc::MachinePassContract &contract() const noexcept override {
+    static const rcc::MachinePassContract Contract{
+        .Name = "MutatingFailure",
+        .Requires = {},
+        .Sets = {},
+        .Clears = {},
+        .RequiredAnalyses = {rcc::MachineFunctionAnalysisManager::id<BlockCountAnalysis>()},
+        .VerificationStage = std::nullopt,
+    };
+    return Contract;
+  }
+
+  [[nodiscard]] rcc::Expected<rcc::MachinePassResult>
+  run(rcc::MachineFunction &Function, const rcc::TargetDescription &,
+      rcc::MachineFunctionAnalysisManager &) override {
+    auto Block = Function.createBasicBlock();
+    if (!Block)
+      return std::unexpected(Block.error());
+    auto Appended = Function.appendBlock(**Block);
+    if (!Appended)
+      return std::unexpected(Appended.error());
+    return rcc::makeUnexpected(rcc::ErrorCode::VerificationError,
+                               "intentional mutating pass failure");
+  }
+};
+
+class ParallelCountingPass final : public rcc::MachineFunctionPass {
+public:
+  explicit ParallelCountingPass(std::atomic<std::uint32_t> &Count) : Count(&Count) {}
+
+  [[nodiscard]] const rcc::MachinePassContract &contract() const noexcept override {
+    static const rcc::MachinePassContract Contract = [] {
+      rcc::MachinePassContract Value{
+          .Name = "ParallelCounting",
+          .Requires = {},
+          .Sets = {},
+          .Clears = {},
+          .RequiredAnalyses = {},
+          .VerificationStage = std::nullopt,
+      };
+      Value.ThreadSafety = rcc::PassThreadSafety::ThreadSafe;
+      return Value;
+    }();
+    return Contract;
+  }
+
+  [[nodiscard]] rcc::Expected<rcc::MachinePassResult>
+  run(rcc::MachineFunction &, const rcc::TargetDescription &,
+      rcc::MachineFunctionAnalysisManager &) override {
+    Count->fetch_add(1, std::memory_order_relaxed);
+    return rcc::MachinePassResult{};
+  }
+
+private:
+  std::atomic<std::uint32_t> *Count;
+};
+
+class RequiresNonThreadSafeAnalysisPass final : public rcc::MachineFunctionPass {
+public:
+  [[nodiscard]] const rcc::MachinePassContract &contract() const noexcept override {
+    static const rcc::MachinePassContract Contract = [] {
+      rcc::MachinePassContract Value{
+          .Name = "RequiresNonThreadSafe",
+          .Requires = {},
+          .Sets = {},
+          .Clears = {},
+          .RequiredAnalyses =
+              {
+                  rcc::MachineFunctionAnalysisManager::id<NonThreadSafeAnalysis>(),
+              },
+          .VerificationStage = std::nullopt,
+      };
+      Value.ThreadSafety = rcc::PassThreadSafety::ThreadSafe;
+      return Value;
+    }();
+    return Contract;
+  }
+
+  [[nodiscard]] rcc::Expected<rcc::MachinePassResult>
+  run(rcc::MachineFunction &, const rcc::TargetDescription &,
+      rcc::MachineFunctionAnalysisManager &) override {
+    return rcc::MachinePassResult{};
+  }
+};
+
+class UnitFunctionCountAnalysis final {
+public:
+  struct Result final {
+    std::size_t Count = 0;
+  };
+  [[nodiscard]] static constexpr std::string_view name() noexcept {
+    return "UnitFunctionCount";
+  }
+  [[nodiscard]] static rcc::Expected<Result> run(rcc::CompilationUnit &Unit,
+                                                 const rcc::TargetDescription &,
+                                                 rcc::CompilationUnitAnalysisManager &) {
+    return Result{Unit.functionCount()};
+  }
+};
+
+class ObserveUnitPass final : public rcc::CompilationUnitPass {
+public:
+  [[nodiscard]] const rcc::CompilationUnitPassContract &contract() const noexcept override {
+    static const rcc::CompilationUnitPassContract Contract{
+        .Name = "ObserveUnit",
+        .RequiredAnalyses = {rcc::CompilationUnitAnalysisManager::id<UnitFunctionCountAnalysis>()},
+        .Parameters = {},
+        .DeclaredChanges = {},
+    };
+    return Contract;
+  }
+
+  [[nodiscard]] rcc::Expected<rcc::CompilationUnitPassResult>
+  run(rcc::CompilationUnit &Unit, const rcc::TargetDescription &Target,
+      rcc::CompilationUnitAnalysisManager &Analyses,
+      rcc::MachineFunctionAnalysisManager &) override {
+    auto Count = Analyses.getResult<UnitFunctionCountAnalysis>(Unit, Target);
+    if (!Count)
+      return std::unexpected(Count.error());
+    if ((*Count)->Count != Unit.functionCount()) {
+      return rcc::makeUnexpected(rcc::ErrorCode::VerificationError,
+                                 "unit analysis returned a stale function count");
+    }
+    return rcc::CompilationUnitPassResult{};
+  }
+};
+
+class MutatingUnitFailurePass final : public rcc::CompilationUnitPass {
+public:
+  [[nodiscard]] const rcc::CompilationUnitPassContract &contract() const noexcept override {
+    static const rcc::CompilationUnitPassContract Contract{
+        .Name = "MutatingUnitFailure",
+        .RequiredAnalyses = {rcc::CompilationUnitAnalysisManager::id<UnitFunctionCountAnalysis>()},
+        .Parameters = {},
+        .DeclaredChanges = {rcc::MachinePassChange::BlockLayout},
+    };
+    return Contract;
+  }
+
+  [[nodiscard]] rcc::Expected<rcc::CompilationUnitPassResult>
+  run(rcc::CompilationUnit &Unit, const rcc::TargetDescription &,
+      rcc::CompilationUnitAnalysisManager &, rcc::MachineFunctionAnalysisManager &) override {
+    auto Created = Unit.createMachineFunction("added-before-failure");
+    if (!Created)
+      return std::unexpected(Created.error());
+    return rcc::makeUnexpected(rcc::ErrorCode::VerificationError,
+                               "intentional compilation-unit pass failure");
+  }
+};
+
+void testMachinePassManager(TestContext &Context, const rcc::TargetDescription &Target) {
+  auto Function = rcc::MachineFunction::create("pass", rcc::MachineFunctionStableID::fromValue(2));
+  Context.expect(Function.has_value(), "pass function creation must succeed");
+  if (!Function)
+    return;
+
+  rcc::MachineFunctionAnalysisManager Analyses;
+  Context.expect(Analyses
+                     .registerAnalysis<BlockCountAnalysis>({
+                         .Name = "BlockCount",
+                         .Dependencies = {},
+                         .InvalidatedBy = rcc::MachinePassChanges::all(),
+                         .ThreadSafety = rcc::PassThreadSafety::ThreadSafe,
+                     })
+                     .has_value(),
+                 "pass analysis registration must succeed");
+
+  rcc::MachineFunctionPassManager Pipeline;
+  Context.expect(Pipeline.addPass(std::make_unique<RequiredAnalysisPass>()).has_value(),
+                 "a valid pass must be accepted");
+  auto Run = Pipeline.run(**Function, Target, Analyses);
+  Context.expect(Run.has_value(), "a pass with a materialized required analysis must run");
+
+  auto ChangedFunction =
+      rcc::MachineFunction::create("unreported", rcc::MachineFunctionStableID::fromValue(3));
+  rcc::MachineFunctionAnalysisManager EmptyAnalyses;
+  rcc::MachineFunctionPassManager Detecting(
+      {.VerifyBefore = true, .VerifyEach = true, .DetectUnreportedChanges = true});
+  Context.expect(ChangedFunction &&
+                     Detecting.addPass(std::make_unique<UnreportedChangePass>()).has_value() &&
+                     !Detecting.run(**ChangedFunction, Target, EmptyAnalyses),
+                 "change detection must reject an unreported MachineIR mutation");
+
+  auto FailedFunction =
+      rcc::MachineFunction::create("failed", rcc::MachineFunctionStableID::fromValue(4));
+  rcc::MachineFunctionAnalysisManager FailureAnalyses;
+  Context.expect(FailedFunction && FailureAnalyses
+                                       .registerAnalysis<BlockCountAnalysis>({
+                                           .Name = "BlockCount",
+                                           .Dependencies = {},
+                                           .InvalidatedBy = rcc::MachinePassChanges::all(),
+                                       })
+                                       .has_value(),
+                 "mutating failure analysis fixtures must be valid");
+  rcc::MachineFunctionPassManager FailingPipeline;
+  Context.expect(
+      FailedFunction &&
+          FailingPipeline.addPass(std::make_unique<MutatingFailurePass>()).has_value() &&
+          !FailingPipeline.run(**FailedFunction, Target, FailureAnalyses) &&
+          !FailureAnalyses.hasCached(**FailedFunction,
+                                     rcc::MachineFunctionAnalysisManager::id<BlockCountAnalysis>()),
+      "a pass that mutates and fails must not leave stale function analyses cached");
+}
+
+void testCompilationUnitAndParallelism(TestContext &Context, const rcc::TargetDescription &Target) {
+  rcc::CompilationUnit Unit;
+  for (std::size_t Index = 0; Index < 8; ++Index) {
+    auto Function = Unit.createMachineFunction("f" + std::to_string(Index));
+    Context.expect(Function.has_value(), "parallel test function creation must succeed");
+  }
+
+  std::atomic<std::uint32_t> Runs = 0;
+  rcc::MachineFunctionPassManager Parallel;
+  Context.expect(Parallel.addPass(std::make_unique<ParallelCountingPass>(Runs)).has_value(),
+                 "thread-safe pass registration must succeed");
+  rcc::MachineFunctionAnalysisManager Prototype;
+  auto ParallelRun = Parallel.runFunctions(Unit, Target, Prototype, std::size_t{4});
+  Context.expect(ParallelRun.has_value() && Runs == Unit.functionCount(),
+                 "parallel function execution must visit every function exactly once");
+
+  rcc::MachineFunctionAnalysisManager UnsafePrototype;
+  Context.expect(UnsafePrototype
+                     .registerAnalysis<NonThreadSafeAnalysis>({
+                         .Name = "NonThreadSafe",
+                         .Dependencies = {},
+                         .InvalidatedBy = rcc::MachinePassChanges::all(),
+                         .ThreadSafety = rcc::PassThreadSafety::NotThreadSafe,
+                     })
+                     .has_value(),
+                 "non-thread-safe analysis registration must be explicit");
+  rcc::MachineFunctionPassManager UnsafeParallel;
+  Context.expect(
+      UnsafeParallel.addPass(std::make_unique<RequiresNonThreadSafeAnalysisPass>()).has_value() &&
+          !UnsafeParallel.runFunctions(Unit, Target, UnsafePrototype, std::size_t{4}),
+      "parallel pipelines must reject a required analysis not marked thread-safe");
+
+  rcc::CompilationUnitAnalysisManager UnitAnalyses;
+  Context.expect(UnitAnalyses
+                     .registerAnalysis<UnitFunctionCountAnalysis>({
+                         .Name = "UnitFunctionCount",
+                         .Dependencies = {},
+                         .InvalidatedBy = rcc::MachinePassChanges::all(),
+                     })
+                     .has_value(),
+                 "compilation-unit analysis registration must succeed");
+  rcc::MachineFunctionAnalysisManager FunctionAnalyses;
+  rcc::CompilationUnitPassManager UnitPipeline;
+  Context.expect(UnitPipeline.addPass(std::make_unique<ObserveUnitPass>()).has_value(),
+                 "compilation-unit pass registration must succeed");
+  Context.expect(UnitPipeline.run(Unit, Target, UnitAnalyses, FunctionAnalyses).has_value(),
+                 "compilation-unit pass and analysis must run through their own manager");
+
+  rcc::MachineFunction *FirstFunction = Unit.functionAt(0);
+  Context.expect(
+      FirstFunction != nullptr &&
+          FunctionAnalyses
+              .registerAnalysis<BlockCountAnalysis>({
+                  .Name = "BlockCount",
+                  .Dependencies = {},
+                  .InvalidatedBy = rcc::MachinePassChanges::all(),
+              })
+              .has_value() &&
+          FunctionAnalyses.getResult<BlockCountAnalysis>(*FirstFunction, Target).has_value(),
+      "compilation-unit failure cache fixtures must materialize");
+  rcc::CompilationUnitPassManager FailingUnitPipeline;
+  Context.expect(
+      FirstFunction != nullptr &&
+          FailingUnitPipeline.addPass(std::make_unique<MutatingUnitFailurePass>()).has_value() &&
+          !FailingUnitPipeline.run(Unit, Target, UnitAnalyses, FunctionAnalyses) &&
+          !UnitAnalyses.hasCached(
+              Unit, rcc::CompilationUnitAnalysisManager::id<UnitFunctionCountAnalysis>()) &&
+          !FunctionAnalyses.hasCached(
+              *FirstFunction, rcc::MachineFunctionAnalysisManager::id<BlockCountAnalysis>()),
+      "a mutating compilation-unit failure must clear unit and function analysis caches");
+}
+
+} // namespace
+
+int main() {
+  TestContext Context;
+  auto Target = createTarget();
+  Context.expect(Target.has_value(), "machine pass tests require a valid target description");
+  if (!Target)
+    return Context.result();
+
+  testMachinePassManager(Context, *Target);
+  testCompilationUnitAndParallelism(Context, *Target);
+  return Context.result();
+}