From 92f4708ce7f0c43241b010ec2579d356ed363b73 Mon Sep 17 00:00:00 2001
From: servostar <sven.vogel123@web.de>
Date: Mon, 27 May 2024 13:05:56 +0200
Subject: [PATCH] feature: codegen

---
 src/llvm/backend.c | 45 ++++++++++++++++++++++
 src/llvm/backend.h | 29 ++++++++++++++
 src/llvm/parser.c  | 95 ++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 169 insertions(+)

diff --git a/src/llvm/backend.c b/src/llvm/backend.c
index 5abcb95..8820120 100644
--- a/src/llvm/backend.c
+++ b/src/llvm/backend.c
@@ -1,10 +1,55 @@
 
 #include <codegen/backend.h>
+#include <llvm-c/Core.h>
+#include <llvm-c/TargetMachine.h>
 #include <sys/log.h>
 #include <ast/ast.h>
 #include <llvm/backend.h>
 #include <llvm/parser.h>
 
+Target create_native_target() {
+    Target target;
+
+    target.triple.str = LLVMGetDefaultTargetTriple();
+    target.triple.allocation = LLVM;
+
+    target.cpu.str = LLVMGetHostCPUName();
+    target.cpu.allocation = LLVM;
+
+    target.features.str = LLVMGetHostCPUFeatures();
+    target.features.allocation = LLVM;
+
+    target.opt = LLVMCodeGenLevelDefault;
+    target.reloc = LLVMRelocDefault;
+    target.model = LLVMCodeModelDefault;
+
+    return target;
+}
+
+Target create_target_from_config() {
+    PANIC("NOT IMPLEMENTED");
+}
+
+static void delete_string(String string) {
+    switch (string.allocation) {
+        case LLVM:
+            LLVMDisposeMessage(string.str);
+            break;
+        case LIBC:
+            free(string.str);
+            break;
+        case NONE:
+            break;
+    }
+}
+
+void delete_target(Target target) {
+    delete_string(target.name);
+    delete_string(target.cpu);
+    delete_string(target.features);
+    delete_string(target.triple);
+}
+
 typedef enum LLVMBackendError_t {
     UnresolvedImport
 } LLVMBackendError;
diff --git a/src/llvm/backend.h b/src/llvm/backend.h
index 26ef165..4625aa7 100644
--- a/src/llvm/backend.h
+++ b/src/llvm/backend.h
@@ -2,6 +2,35 @@
 #ifndef LLVM_CODEGEN_BACKEND_H_
 #define LLVM_CODEGEN_BACKEND_H_
 
+#include <llvm-c/TargetMachine.h>
+
+enum StringAllocation_t {
+    LLVM,
+    LIBC,
+    NONE
+};
+
+typedef struct String_t {
+    enum StringAllocation_t allocation;
+    char* str;
+} String;
+
+typedef struct Target_t {
+    String name;
+    String triple;
+    String cpu;
+    String features;
+    LLVMCodeGenOptLevel opt;
+    LLVMRelocMode reloc;
+    LLVMCodeModel model;
+} Target;
+
+Target create_native_target();
+
+Target create_target_from_config();
+
+void delete_target(Target target);
+
 void llvm_backend_init(void);
 
 #endif // LLVM_CODEGEN_BACKEND_H_
diff --git a/src/llvm/parser.c b/src/llvm/parser.c
index e143d0c..4ff827d 100644
--- a/src/llvm/parser.c
+++ b/src/llvm/parser.c
@@ -1,14 +1,103 @@
 
 #include <codegen/backend.h>
 #include <llvm-c/Core.h>
+#include <llvm-c/Target.h>
+#include <llvm-c/TargetMachine.h>
 #include <llvm-c/Types.h>
 #include <llvm/parser.h>
 #include <llvm/types.h>
 #include <llvm/variables.h>
 #include <set/types.h>
+#include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
+
+#include "llvm/backend.h"
+
+BackendError export_IR(LLVMBackendCompileUnit* unit) {
+    BackendError err = SUCCESS;
+
+    char* ir = LLVMPrintModuleToString(unit->module);
+
+    FILE* output = fopen("module.ll", "w");
+    if (output == NULL) {
+        err = new_backend_impl_error(Implementation, NULL,
+                                     "unable to open file for writing");
+        LLVMDisposeMessage(ir);
+    }
+
+    fprintf(output, "%s", ir);
+    fflush(output);
+    fclose(output);
+
+    LLVMDisposeMessage(ir);
+
+    return err;
+}
+
+BackendError export_object(LLVMBackendCompileUnit* unit, const Target* target) {
+    LLVMTargetRef llvm_target = NULL;
+    char* error = NULL;
+
+    if (LLVMGetTargetFromTriple(target->triple.str, &llvm_target, &error) !=
+        0) {
+        BackendError err =
+            new_backend_impl_error(Implementation, NULL, strdup(error));
+        LLVMDisposeMessage(error);
+        return err;
+    }
+
+    LLVMTargetMachineRef target_machine = LLVMCreateTargetMachine(
+        llvm_target, target->triple.str, target->cpu.str, target->features.str,
+        target->opt, target->reloc, target->model);
+
+    LLVMCodeGenFileType file_type = LLVMObjectFile;
+
+    if (LLVMTargetMachineEmitToFile(target_machine, unit->module, "output",
+                                    file_type, &error) != 0) {
+        BackendError err =
+            new_backend_impl_error(Implementation, NULL, strdup(error));
+        LLVMDisposeMessage(error);
+        return err;
+    }
+
+    return SUCCESS;
+}
+
+void list_available_targets() {
+    LLVMInitializeAllTargetInfos();
+
+    printf("Available targets:\n");
+
+    LLVMTargetRef target = LLVMGetFirstTarget();
+    while (target) {
+        const char* name = LLVMGetTargetName(target);
+        const char* desc = LLVMGetTargetDescription(target);
+        printf(" - %s: (%s)\n", name, desc);
+
+        target = LLVMGetNextTarget(target);
+    }
+
+    char* default_triple = LLVMGetDefaultTargetTriple();
+
+    printf("Default: %s\n", default_triple);
+
+    LLVMDisposeMessage(default_triple);
+}
+
+BackendError export_module(LLVMBackendCompileUnit* unit, const Target* target) {
+    BackendError err = SUCCESS;
+
+    export_object(unit, target);
+
+    return err;
+}
 
 BackendError parse_module(const Module* module, void**) {
+    if (module == NULL) {
+        return new_backend_impl_error(Implementation, NULL, "no module");
+    }
+
     LLVMBackendCompileUnit* unit = malloc(sizeof(LLVMBackendCompileUnit));
 
     // we start with a LLVM module
@@ -32,6 +121,12 @@ BackendError parse_module(const Module* module, void**) {
         err = new_backend_impl_error(Implementation, NULL, err_msg);
     }
 
+    Target target = create_native_target();
+
+    export_module(unit, &target);
+
+    delete_target(target);
+
     delete_global_scope(global_scope);
 
     LLVMDisposeModule(unit->module);