[MIR] Add machine instruction parser and printer

Parse MachineFunction bodies in two passes and serialize the same MachineIR model in complete or readable form. Extend instruction attachments and memory operands required by the fixed LLVM MIR grammar, and cover deterministic parse-print round trips.

2 files changed, 130 insertions, 0 deletions

diff --git a/backend/include/rcc/MIR/MIParser.h b/backend/include/rcc/MIR/MIParser.h
new file mode 100644
index 0000000..978e928
--- /dev/null
+++ b/backend/include/rcc/MIR/MIParser.h
@@ -0,0 +1,95 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#ifndef RCC_MIR_MIPARSER_H
+#define RCC_MIR_MIPARSER_H
+
+#include "rcc/CodeGen/MachineIRTypes.h"
+#include "rcc/CodeGen/MachineMetadata.h"
+#include "rcc/Support/Error.h"
+#include "rcc/Support/TextDiagnostic.h"
+
+#include <cstddef>
+#include <cstdint>
+#include <memory>
+#include <optional>
+#include <span>
+#include <string>
+#include <vector>
+
+namespace rcc {
+
+class MachineFunction;
+class TargetDescription;
+
+namespace mir {
+
+struct MIFrameObjectSlot final {
+  std::uint32_t TextID = 0;
+  FrameIndex Index;
+  std::optional<std::string> Name;
+};
+
+struct MIConstantPoolSlot final {
+  std::uint32_t TextID = 0;
+  ConstantPoolIndex Index;
+};
+
+struct MIJumpTableSlot final {
+  std::uint32_t TextID = 0;
+  JumpTableIndex Index;
+};
+
+struct MIMetadataSlot final {
+  std::uint32_t TextID = 0;
+  MachineMetadataReference Reference;
+};
+
+struct MISyncScopeSlot final {
+  std::string Name;
+  SyncScopeID ID;
+};
+
+struct MIParserContext final {
+  std::vector<MIFrameObjectSlot> StackObjects;
+  std::vector<MIFrameObjectSlot> FixedStackObjects;
+  std::vector<MIConstantPoolSlot> ConstantPoolItems;
+  std::vector<MIJumpTableSlot> JumpTables;
+  std::vector<MIMetadataSlot> Metadata;
+  std::vector<MISyncScopeSlot> SyncScopes;
+  std::uint32_t DefaultPointerSizeInBits = 0;
+};
+
+struct MIParserOptions final {
+  std::size_t MaximumTokens = std::size_t{1} << 24U;
+  std::size_t MaximumTokenLength = std::size_t{1} << 24U;
+  std::size_t MaximumBlocks = std::size_t{1} << 20U;
+  std::size_t MaximumInstructions = std::size_t{1} << 24U;
+  std::size_t MaximumOperandsPerInstruction = std::size_t{1} << 20U;
+  std::size_t MaximumMemoryOperandsPerInstruction = std::size_t{1} << 20U;
+};
+
+class MIParser final {
+public:
+  MIParser(MachineFunction &Function, const TargetDescription &Target, std::string SourceName,
+           std::string SourceText, MIParserContext Context = {}, MIParserOptions Options = {});
+  MIParser(const MIParser &) = delete;
+  MIParser &operator=(const MIParser &) = delete;
+  MIParser(MIParser &&) noexcept;
+  MIParser &operator=(MIParser &&) noexcept;
+  ~MIParser();
+
+  [[nodiscard]] Expected<void> parse();
+
+  [[nodiscard]] const TextSource &source() const noexcept;
+  [[nodiscard]] std::span<const TextDiagnostic> diagnostics() const noexcept;
+  [[nodiscard]] bool failed() const noexcept;
+
+private:
+  class Impl;
+  std::unique_ptr<Impl> Implementation;
+};
+
+} // namespace mir
+} // namespace rcc
+
+#endif // RCC_MIR_MIPARSER_H
diff --git a/backend/include/rcc/MIR/MIPrinter.h b/backend/include/rcc/MIR/MIPrinter.h
new file mode 100644
index 0000000..663859e
--- /dev/null
+++ b/backend/include/rcc/MIR/MIPrinter.h
@@ -0,0 +1,35 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#ifndef RCC_MIR_MIPRINTER_H
+#define RCC_MIR_MIPRINTER_H
+
+#include "rcc/MIR/MIParser.h"
+#include "rcc/Support/Error.h"
+
+#include <string>
+
+namespace rcc {
+
+class MachineFunction;
+class TargetDescription;
+
+namespace mir {
+
+enum class MIPrintMode : unsigned char {
+  Complete,
+  Readable,
+};
+
+struct MIPrinterOptions final {
+  MIPrintMode Mode = MIPrintMode::Complete;
+};
+
+[[nodiscard]] Expected<std::string> printMachineFunctionBody(const MachineFunction &Function,
+                                                             const TargetDescription &Target,
+                                                             const MIParserContext &Context = {},
+                                                             MIPrinterOptions Options = {});
+
+} // namespace mir
+} // namespace rcc
+
+#endif // RCC_MIR_MIPRINTER_H