Merge pull request 'Furvm backend for furc' (#18) from furvm-gen into master

Reviewed-on: #18

.clang-tidy

@@ -30,7 +30,8 @@ Checks: >
   -cppcoreguidelines-owning-memory,
   -cppcoreguidelines-non-private-member-variables-in-classes,
   -cppcoreguidelines-pro-bounds-avoid-unchecked-container-access,
-  -cppcoreguidelines-pro-bounds-array-to-pointer-decay
+  -cppcoreguidelines-pro-bounds-array-to-pointer-decay,
+  -bugprone-forward-declaration-namespace
 
 WarningsAsErrors: "*"
 

furc/CMakeLists.txt

@@ -4,7 +4,7 @@ add_library(libfurc ${FURC_SRCS} ${FURC_HDRS})
 target_include_directories(libfurc PUBLIC include/)
 target_compile_definitions(libfurc PRIVATE LIBFURC)
 set_target_properties(libfurc PROPERTIES PREFIX "")
-target_link_libraries(libfurc PUBLIC furlang)
+target_link_libraries(libfurc PUBLIC furlang libfurvm)
 add_executable(furc src/main.cpp)
 target_link_libraries(furc PRIVATE libfurc)
 

furc/include/furc/back/furvm.hpp

@@ -0,0 +1,43 @@
+#ifndef FURC_BACK_FURVM_HPP
+#define FURC_BACK_FURVM_HPP
+
+#include "furlang/ir/operand.hpp"
+
+#include <cstddef>
+#include <furlang/ir/function.hpp>
+#include <furlang/ir/instruction.hpp>
+#include <furlang/ir/module.hpp>
+#include <furvm/fwd.hpp>
+#include <furvm/module.hpp>
+#include <unordered_map>
+#include <vector>
+
+namespace furc {
+namespace back {
+
+class furvm_generator {
+public:
+    furvm_generator() = default;
+public:
+    static furvm::mod generate(furlang::ir::mod& mod);
+private:
+    static void generate_function(furvm::mod& mod, const furlang::ir::function& function);
+
+    struct function_context {
+        std::unordered_map<furlang::ir::block_index, std::size_t>              blockOffsets;
+        std::unordered_map<furlang::ir::block_index, std::vector<std::size_t>> incompleteJumps;
+
+        std::unordered_map<furlang::ir::register_operand, furvm::variable_t> variables;
+        furvm::variable_t                                                    variableCounter{ 0 };
+    };
+
+    static void generate_instruction(furvm::mod& mod, function_context& ctx, const furlang::ir::instruction& instr);
+    static void generate_operand(furvm::mod& mod, function_context& ctx, const furlang::ir::operand& operand);
+
+    static void generate_jump(furvm::mod& mod, function_context& ctx, furlang::ir::block_index block, bool conditional);
+};
+
+} // namespace back
+} // namespace furc
+
+#endif // FURC_BACK_FURVM_HPP

furc/src/back/furvm.cpp

@@ -0,0 +1,143 @@
+#include "furc/back/furvm.hpp"
+
+#include "furlang/ir/instruction.hpp"
+
+#include <furvm/instruction.hpp>
+#include <stdexcept>
+
+namespace furc::back {
+
+furvm::mod furvm_generator::generate(furlang::ir::mod& mod) {
+    furvm::mod vmMod;
+
+    for (const auto& function : mod.functions()) {
+        generate_function(vmMod, *function);
+    }
+
+    return vmMod;
+}
+
+void furvm_generator::generate_function(furvm::mod& mod, const furlang::ir::function& function) {
+    auto func = mod.emplace_function(function.name(), mod.bytecode().size());
+    func.dispatch();
+
+    function_context ctx;
+    for (furlang::ir::block_index idx = 0; idx < function.blocks().size(); ++idx) {
+        if (auto it = ctx.incompleteJumps.find(idx); it != ctx.incompleteJumps.end()) {
+            for (std::size_t offset : it->second) {
+                mod.bytecode()[offset] = mod.bytecode().size() - offset - 1;
+            }
+            ctx.incompleteJumps.erase(it);
+        }
+
+        ctx.blockOffsets[idx] = mod.bytecode().size();
+        for (const auto& instr : function.blocks()[idx]->instructions())
+            generate_instruction(mod, ctx, *instr);
+        generate_instruction(mod, ctx, *function.blocks()[idx]->exit());
+    }
+}
+
+static inline furvm::instruction_t binary_op_type(furlang::ir::binary_op_instruction_t type) {
+    switch (type) {
+    case furlang::ir::binary_op_instruction_t::Add: return furvm::instruction_t::Add;
+    case furlang::ir::binary_op_instruction_t::Sub: return furvm::instruction_t::Sub;
+    case furlang::ir::binary_op_instruction_t::Mul: return furvm::instruction_t::Mul;
+    case furlang::ir::binary_op_instruction_t::Div: return furvm::instruction_t::Div;
+    case furlang::ir::binary_op_instruction_t::Mod: return furvm::instruction_t::Mod;
+    case furlang::ir::binary_op_instruction_t::Eq: return furvm::instruction_t::Equals;
+    case furlang::ir::binary_op_instruction_t::NotEq: return furvm::instruction_t::NotEquals;
+    case furlang::ir::binary_op_instruction_t::LessThan: return furvm::instruction_t::LessThan;
+    case furlang::ir::binary_op_instruction_t::GreaterThan: return furvm::instruction_t::GreaterThan;
+    case furlang::ir::binary_op_instruction_t::LessEq: return furvm::instruction_t::LessEqual;
+    case furlang::ir::binary_op_instruction_t::GreaterEq: return furvm::instruction_t::GreaterEqual;
+    }
+    throw std::runtime_error("unreachable");
+}
+
+void furvm_generator::generate_instruction(furvm::mod& mod,
+    function_context&                                  ctx,
+    const furlang::ir::instruction&                    instr) {
+    for (const auto& operand : instr.sources())
+        generate_operand(mod, ctx, *operand);
+
+    switch (instr.type()) {
+    case furlang::ir::instruction_t::Assign: {
+        if (ctx.variables.find(instr.destination().reg()) == ctx.variables.end()) {
+            ctx.variables[instr.destination().reg()] = ctx.variableCounter++;
+        }
+        auto var = ctx.variables[instr.destination().reg()];
+        mod.bytecode().push_back(static_cast<furvm::byte>(furvm::instruction_t::Store));
+        mod.bytecode().push_back((var >> 0) & 0xFF);
+        mod.bytecode().push_back((var >> 8) & 0xFF);
+        static_assert(sizeof(var) == 2, "sizeof(furvm::variable_t) has changed");
+    } break;
+    case furlang::ir::instruction_t::BinaryOp: {
+        const auto& op = dynamic_cast<const furlang::ir::binary_op_instruction&>(instr);
+        mod.bytecode().push_back(static_cast<furvm::byte>(binary_op_type(op.op_type())));
+
+        if (ctx.variables.find(instr.destination().reg()) == ctx.variables.end()) {
+            ctx.variables[instr.destination().reg()] = ctx.variableCounter++;
+        }
+        auto var = ctx.variables[instr.destination().reg()];
+        mod.bytecode().push_back(static_cast<furvm::byte>(furvm::instruction_t::Store));
+        mod.bytecode().push_back((var >> 0) & 0xFF);
+        mod.bytecode().push_back((var >> 8) & 0xFF);
+        static_assert(sizeof(var) == 2, "sizeof(furvm::variable_t) has changed");
+    } break;
+    case furlang::ir::instruction_t::Branch: {
+        const auto& branch = dynamic_cast<const furlang::ir::branch_instruction&>(instr);
+        generate_jump(mod, ctx, branch.block(), false);
+    } break;
+    case furlang::ir::instruction_t::BranchCond: {
+        const auto& branch = dynamic_cast<const furlang::ir::branch_cond_instruction&>(instr);
+        generate_jump(mod, ctx, branch.if_block(), true);
+        generate_jump(mod, ctx, branch.else_block(), false);
+    } break;
+    case furlang::ir::instruction_t::Return: {
+        if (instr.sources().empty()) {
+            mod.bytecode().push_back(static_cast<furvm::byte>(furvm::instruction_t::Return));
+        } else {
+            mod.bytecode().push_back(static_cast<furvm::byte>(furvm::instruction_t::ReturnValue));
+        }
+    } break;
+    case furlang::ir::instruction_t::Call:
+    case furlang::ir::instruction_t::Alloca: throw std::runtime_error("unimplemented instruction");
+    case furlang::ir::instruction_t::Phi: throw std::runtime_error("unreachable");
+    }
+}
+
+void furvm_generator::generate_operand(furvm::mod& mod, function_context& ctx, const furlang::ir::operand& operand) {
+    switch (operand.type()) {
+    case furlang::ir::operand_t::Register: {
+        if (ctx.variables.find(operand.reg()) == ctx.variables.end()) throw std::runtime_error("unregistered register");
+        auto var = ctx.variables[operand.reg()];
+        mod.bytecode().push_back(static_cast<furvm::byte>(furvm::instruction_t::Load));
+        mod.bytecode().push_back((var >> 0) & 0xFF);
+        mod.bytecode().push_back((var >> 8) & 0xFF);
+        static_assert(sizeof(var) == 2, "sizeof(furvm::variable_t) has changed");
+    } break;
+    case furlang::ir::operand_t::Integer: {
+        mod.bytecode().push_back(static_cast<furvm::byte>(furvm::instruction_t::PushB2I));
+        mod.bytecode().push_back(operand.integer());
+    } break;
+    case furlang::ir::operand_t::Variable:
+    case furlang::ir::operand_t::String: throw std::runtime_error("unimplemented operand");
+    case furlang::ir::operand_t::None: throw std::runtime_error("unreachable");
+    }
+}
+
+void furvm_generator::generate_jump(furvm::mod& mod,
+    function_context&                           ctx,
+    furlang::ir::block_index                    block,
+    bool                                        conditional) {
+    mod.bytecode().push_back(
+        static_cast<furvm::byte>(conditional ? furvm::instruction_t::JumpNotZero : furvm::instruction_t::Jump));
+    if (auto it = ctx.blockOffsets.find(block); it != ctx.blockOffsets.end()) {
+        mod.bytecode().push_back(it->second - mod.bytecode().size() - 1);
+    } else {
+        ctx.incompleteJumps[block].push_back(mod.bytecode().size());
+        mod.bytecode().push_back(0);
+    }
+}
+
+} // namespace furc::back

furc/src/main.cpp

@@ -1,11 +1,13 @@
 #ifndef LIBFURC
 
 #include "furc/ast/program.hpp"
+#include "furc/back/furvm.hpp"
 #include "furc/front/ir_generator.hpp"
 #include "furc/front/parser.hpp"
 #include "furc/front/post_process.hpp"
 #include "furlang/arena.hpp"
 
+#include <fstream>
 #include <iostream>
 
 int main(void) {
@@ -54,6 +56,9 @@ int main(void) {
             }
         }
 
+        std::ofstream file("./a.fmod", std::ios::binary);
+        furc::back::furvm_generator::generate(mod).serialize(file);
+
         return 0;
     } catch (...) {
         std::cerr << "Caught an exception in main!\n";

furvm/include/furvm/handle.hpp

@@ -226,6 +226,11 @@ public:
      * @return The value reference.
      */
     const_reference value() const { return m_value->second; }
+public:
+    /**
+     * @brief Invalidates the handle without releasing.
+     */
+    void dispatch() { m_value = nullptr; }
 private:
     pair_type* m_value = nullptr;
 };