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-rw-r--r--codegen.c595
1 files changed, 0 insertions, 595 deletions
diff --git a/codegen.c b/codegen.c
deleted file mode 100644
index a1167d4..0000000
--- a/codegen.c
+++ /dev/null
@@ -1,595 +0,0 @@
-enum GenMode {
- GenMode_lval,
- GenMode_rval,
-};
-typedef enum GenMode GenMode;
-
-struct CodeGen {
- int next_label;
- int* loop_labels;
- AstNode* current_func;
-};
-typedef struct CodeGen CodeGen;
-
-CodeGen* codegen_new() {
- CodeGen* g = calloc(1, sizeof(CodeGen));
- g->next_label = 1;
- g->loop_labels = calloc(1024, sizeof(int));
- return g;
-}
-
-int codegen_new_label(CodeGen* g) {
- int new_label = g->next_label;
- ++g->next_label;
- return new_label;
-}
-
-void codegen_expr(CodeGen* g, AstNode* ast, GenMode gen_mode);
-void codegen_stmt(CodeGen* g, AstNode* ast);
-
-const char* param_reg(int n) {
- if (n == 0) {
- return "rdi";
- } else if (n == 1) {
- return "rsi";
- } else if (n == 2) {
- return "rdx";
- } else if (n == 3) {
- return "rcx";
- } else if (n == 4) {
- return "r8";
- } else if (n == 5) {
- return "r9";
- } else {
- unreachable();
- }
-}
-
-void codegen_func_prologue(CodeGen* g, AstNode* ast) {
- printf(" push rbp\n");
- printf(" mov rbp, rsp\n");
- for (int i = 0; i < ast->node_params->node_len; ++i) {
- printf(" push %s\n", param_reg(i));
- }
- printf(" sub rsp, %d\n", ast->node_stack_size);
-}
-
-void codegen_func_epilogue(CodeGen* g, AstNode* ast) {
- printf(" mov rsp, rbp\n");
- printf(" pop rbp\n");
- printf(" ret\n");
-}
-
-void codegen_int_expr(CodeGen* g, AstNode* ast) {
- printf(" push %d\n", ast->node_int_value);
-}
-
-void codegen_str_expr(CodeGen* g, AstNode* ast) {
- printf(" mov rax, OFFSET FLAG:.Lstr__%d\n", ast->node_idx);
- printf(" push rax\n");
-}
-
-void codegen_unary_expr(CodeGen* g, AstNode* ast) {
- codegen_expr(g, ast->node_operand, GenMode_rval);
- if (ast->node_op == TokenKind_not) {
- printf(" pop rax\n");
- printf(" mov rdi, 0\n");
- printf(" cmp rax, rdi\n");
- printf(" sete al\n");
- printf(" movzb rax, al\n");
- printf(" push rax\n");
- } else {
- unreachable();
- }
-}
-
-void codegen_ref_expr(CodeGen* g, AstNode* ast, GenMode gen_mode) {
- codegen_expr(g, ast->node_operand, GenMode_lval);
-}
-
-// "reg" stores the address of the expression to be pushed.
-void codegen_push_expr(const char* reg, int size) {
- if (size == 1) {
- printf(" movsx %s, BYTE PTR [%s]\n", reg, reg);
- printf(" push %s\n", reg);
- } else if (size == 2) {
- printf(" movsx %s, WORD PTR [%s]\n", reg, reg);
- printf(" push %s\n", reg);
- } else if (size == 4) {
- printf(" movsxd %s, DWORD PTR [%s]\n", reg, reg);
- printf(" push %s\n", reg);
- } else if (size == 8) {
- printf(" mov %s, [%s]\n", reg, reg);
- printf(" push %s\n", reg);
- } else {
- // Perform bitwise copy. Use r10 register as temporary space.
- // Note: rsp must be aligned to 8.
- printf(" sub rsp, %d\n", to_aligned(size, 8));
- for (int i = 0; i < size; ++i) {
- // Copy a sinle byte from the address that "reg" points to to the stack via r10 register.
- printf(" mov r10b, [%s+%d]\n", reg, i);
- printf(" mov [rsp+%d], r10b\n", i);
- }
- }
-}
-
-void codegen_lval2rval(Type* ty) {
- if (ty->kind == TypeKind_array) {
- return;
- }
-
- printf(" pop rax\n");
- codegen_push_expr("rax", type_sizeof(ty));
-}
-
-void codegen_deref_expr(CodeGen* g, AstNode* ast, GenMode gen_mode) {
- codegen_expr(g, ast->node_operand, GenMode_rval);
- if (gen_mode == GenMode_rval) {
- codegen_lval2rval(ast->node_operand->ty->base);
- }
-}
-
-void codegen_logical_expr(CodeGen* g, AstNode* ast) {
- int label = codegen_new_label(g);
-
- if (ast->node_op == TokenKind_andand) {
- codegen_expr(g, ast->node_lhs, GenMode_rval);
- printf(" pop rax\n");
- printf(" cmp rax, 0\n");
- printf(" je .Lelse%d\n", label);
- codegen_expr(g, ast->node_rhs, GenMode_rval);
- printf(" jmp .Lend%d\n", label);
- printf(".Lelse%d:\n", label);
- printf(" push 0\n");
- printf(".Lend%d:\n", label);
- } else {
- codegen_expr(g, ast->node_lhs, GenMode_rval);
- printf(" pop rax\n");
- printf(" cmp rax, 0\n");
- printf(" je .Lelse%d\n", label);
- printf(" push 1\n");
- printf(" jmp .Lend%d\n", label);
- printf(".Lelse%d:\n", label);
- codegen_expr(g, ast->node_rhs, GenMode_rval);
- printf(".Lend%d:\n", label);
- }
-}
-
-void codegen_binary_expr(CodeGen* g, AstNode* ast, GenMode gen_mode) {
- codegen_expr(g, ast->node_lhs, gen_mode);
- codegen_expr(g, ast->node_rhs, gen_mode);
- printf(" pop rdi\n");
- printf(" pop rax\n");
- if (ast->node_op == TokenKind_plus) {
- printf(" add rax, rdi\n");
- } else if (ast->node_op == TokenKind_minus) {
- printf(" sub rax, rdi\n");
- } else if (ast->node_op == TokenKind_star) {
- printf(" imul rax, rdi\n");
- } else if (ast->node_op == TokenKind_slash) {
- printf(" cqo\n");
- printf(" idiv rdi\n");
- } else if (ast->node_op == TokenKind_percent) {
- printf(" cqo\n");
- printf(" idiv rdi\n");
- printf(" mov rax, rdx\n");
- } else if (ast->node_op == TokenKind_or) {
- printf(" or rax, rdi\n");
- } else if (ast->node_op == TokenKind_lshift) {
- printf(" mov rcx, rdi\n");
- printf(" shl rax, cl\n");
- } else if (ast->node_op == TokenKind_rshift) {
- // TODO: check if the operand is signed or unsigned
- printf(" mov rcx, rdi\n");
- printf(" sar rax, cl\n");
- } else if (ast->node_op == TokenKind_eq) {
- printf(" cmp rax, rdi\n");
- printf(" sete al\n");
- printf(" movzb rax, al\n");
- } else if (ast->node_op == TokenKind_ne) {
- printf(" cmp rax, rdi\n");
- printf(" setne al\n");
- printf(" movzb rax, al\n");
- } else if (ast->node_op == TokenKind_lt) {
- printf(" cmp rax, rdi\n");
- printf(" setl al\n");
- printf(" movzb rax, al\n");
- } else if (ast->node_op == TokenKind_le) {
- printf(" cmp rax, rdi\n");
- printf(" setle al\n");
- printf(" movzb rax, al\n");
- } else {
- unreachable();
- }
- printf(" push rax\n");
-}
-
-void codegen_cond_expr(CodeGen* g, AstNode* ast, GenMode gen_mode) {
- int label = codegen_new_label(g);
-
- codegen_expr(g, ast->node_cond, GenMode_rval);
- printf(" pop rax\n");
- printf(" cmp rax, 0\n");
- printf(" je .Lelse%d\n", label);
- codegen_expr(g, ast->node_then, gen_mode);
- printf(" jmp .Lend%d\n", label);
- printf(".Lelse%d:\n", label);
- codegen_expr(g, ast->node_else, gen_mode);
- printf(".Lend%d:\n", label);
-}
-
-void codegen_assign_expr_helper(CodeGen* g, AstNode* ast) {
- if (ast->node_op == TokenKind_assign) {
- return;
- }
-
- printf(" pop rdi\n");
- printf(" push [rsp]\n");
- codegen_lval2rval(ast->node_lhs->ty);
- printf(" pop rax\n");
-
- if (ast->node_op == TokenKind_assign_add) {
- printf(" add rax, rdi\n");
- } else if (ast->node_op == TokenKind_assign_sub) {
- printf(" sub rax, rdi\n");
- } else if (ast->node_op == TokenKind_assign_mul) {
- printf(" imul rax, rdi\n");
- } else if (ast->node_op == TokenKind_assign_div) {
- printf(" cqo\n");
- printf(" idiv rdi\n");
- } else if (ast->node_op == TokenKind_assign_mod) {
- printf(" cqo\n");
- printf(" idiv rdi\n");
- printf(" mov rax, rdx\n");
- } else {
- unreachable();
- }
-
- printf(" push rax\n");
-}
-
-void codegen_assign_expr(CodeGen* g, AstNode* ast) {
- int sizeof_lhs = type_sizeof(ast->node_lhs->ty);
- int sizeof_rhs = type_sizeof(ast->node_rhs->ty);
-
- codegen_expr(g, ast->node_lhs, GenMode_lval);
- codegen_expr(g, ast->node_rhs, GenMode_rval);
- codegen_assign_expr_helper(g, ast);
- if (sizeof_lhs == 1) {
- printf(" pop rdi\n");
- printf(" pop rax\n");
- printf(" mov BYTE PTR [rax], dil\n");
- printf(" push rdi\n");
- } else if (sizeof_lhs == 2) {
- printf(" pop rdi\n");
- printf(" pop rax\n");
- printf(" mov WORD PTR [rax], di\n");
- printf(" push rdi\n");
- } else if (sizeof_lhs == 4) {
- printf(" pop rdi\n");
- printf(" pop rax\n");
- printf(" mov DWORD PTR [rax], edi\n");
- printf(" push rdi\n");
- } else if (sizeof_lhs == 8) {
- printf(" pop rdi\n");
- printf(" pop rax\n");
- printf(" mov [rax], rdi\n");
- printf(" push rdi\n");
- } else {
- if (ast->node_op != TokenKind_assign) {
- unimplemented();
- }
- // Note: rsp must be aligned to 8.
- int aligned_size = to_aligned(sizeof_lhs, 8);
- printf(" mov rax, [rsp+%d]\n", aligned_size);
- // Perform bitwise copy. Use r10 register as temporary space.
- for (int i = 0; i < aligned_size; ++i) {
- // Copy a sinle byte from the stack to the address that rax points to via r10 register.
- printf(" mov r10b, [rsp+%d]\n", i);
- printf(" mov [rax+%d], r10b\n", i);
- }
- // Pop the RHS value and the LHS address.
- printf(" add rsp, %d\n", aligned_size + 8);
- // TODO: dummy
- printf(" push 0\n");
- }
-}
-
-void codegen_func_call(CodeGen* g, AstNode* ast) {
- const char* func_name = ast->name;
-
- if (strcmp(func_name, "__ducc_va_start") == 0) {
- int stack_size = g->current_func->node_stack_size;
- printf(" # __ducc_va_start BEGIN\n");
- for (int i = 0; i < 6; ++i) {
- printf(" mov rax, %s\n", param_reg(i));
- printf(" mov [rbp-%d], rax\n", 8 + (stack_size - 4 - i) * 8);
- }
- AstNode* va_list_args = ast->node_args->node_items;
- codegen_expr(g, va_list_args, GenMode_lval);
- printf(" pop rdi\n");
- printf(" mov rax, rbp\n");
- printf(" sub rax, %d\n", 8 + (stack_size - 1) * 8);
- printf(" mov [rdi], rax\n");
- printf(" mov DWORD PTR [rax], 8\n");
- printf(" mov DWORD PTR [rax+4], 0\n");
- printf(" mov QWORD PTR [rax+8], 0\n");
- printf(" mov rdi, rbp\n");
- printf(" sub rdi, %d\n", 8 + (stack_size - 4) * 8);
- printf(" mov QWORD PTR [rax+16], rdi\n");
- printf(" # __ducc_va_start END\n");
- return;
- }
-
- AstNode* args = ast->node_args;
- for (int i = 0; i < args->node_len; ++i) {
- AstNode* arg = args->node_items + i;
- codegen_expr(g, arg, GenMode_rval);
- }
- for (int i = args->node_len - 1; i >= 0; --i) {
- printf(" pop %s\n", param_reg(i));
- }
-
- int label = codegen_new_label(g);
-
- printf(" mov rax, rsp\n");
- printf(" and rax, 15\n");
- printf(" cmp rax, 0\n");
- printf(" je .Laligned%d\n", label);
-
- printf(" mov rax, 0\n");
- printf(" sub rsp, 8\n");
- printf(" call %s\n", func_name);
- printf(" add rsp, 8\n");
- printf(" push rax\n");
-
- printf(" jmp .Lend%d\n", label);
- printf(".Laligned%d:\n", label);
-
- printf(" mov rax, 0\n");
- printf(" call %s\n", func_name);
- printf(" push rax\n");
-
- printf(".Lend%d:\n", label);
-}
-
-void codegen_lvar(CodeGen* g, AstNode* ast, GenMode gen_mode) {
- printf(" mov rax, rbp\n");
- printf(" sub rax, %d\n", ast->node_stack_offset);
- printf(" push rax\n");
- if (gen_mode == GenMode_rval) {
- codegen_lval2rval(ast->ty);
- }
-}
-
-void codegen_gvar(CodeGen* g, AstNode* ast, GenMode gen_mode) {
- printf(" lea rax, %s[rip]\n", ast->name);
- printf(" push rax\n");
- if (gen_mode == GenMode_rval) {
- codegen_lval2rval(ast->ty);
- }
-}
-
-void codegen_composite_expr(CodeGen* g, AstNode* ast) {
- // Standard C does not have composite expression, but ducc internally has.
- for (int i = 0; i < ast->node_len; ++i) {
- AstNode* expr = ast->node_items + i;
- codegen_expr(g, expr, GenMode_rval);
- if (i != ast->node_len - 1) {
- // TODO: the expression on the stack can be more than 8 bytes.
- printf(" pop rax\n");
- }
- }
-}
-
-void codegen_expr(CodeGen* g, AstNode* ast, GenMode gen_mode) {
- if (ast->kind == AstNodeKind_int_expr) {
- codegen_int_expr(g, ast);
- } else if (ast->kind == AstNodeKind_str_expr) {
- codegen_str_expr(g, ast);
- } else if (ast->kind == AstNodeKind_unary_expr) {
- codegen_unary_expr(g, ast);
- } else if (ast->kind == AstNodeKind_ref_expr) {
- codegen_ref_expr(g, ast, gen_mode);
- } else if (ast->kind == AstNodeKind_deref_expr) {
- codegen_deref_expr(g, ast, gen_mode);
- } else if (ast->kind == AstNodeKind_binary_expr) {
- codegen_binary_expr(g, ast, gen_mode);
- } else if (ast->kind == AstNodeKind_cond_expr) {
- codegen_cond_expr(g, ast, gen_mode);
- } else if (ast->kind == AstNodeKind_logical_expr) {
- codegen_logical_expr(g, ast);
- } else if (ast->kind == AstNodeKind_assign_expr) {
- codegen_assign_expr(g, ast);
- } else if (ast->kind == AstNodeKind_func_call) {
- codegen_func_call(g, ast);
- } else if (ast->kind == AstNodeKind_lvar) {
- codegen_lvar(g, ast, gen_mode);
- } else if (ast->kind == AstNodeKind_gvar) {
- codegen_gvar(g, ast, gen_mode);
- } else if (ast->kind == AstNodeKind_list) {
- codegen_composite_expr(g, ast);
- } else {
- unreachable();
- }
-}
-
-void codegen_return_stmt(CodeGen* g, AstNode* ast) {
- if (ast->node_expr) {
- codegen_expr(g, ast->node_expr, GenMode_rval);
- printf(" pop rax\n");
- }
- codegen_func_epilogue(g, ast);
-}
-
-void codegen_if_stmt(CodeGen* g, AstNode* ast) {
- int label = codegen_new_label(g);
-
- codegen_expr(g, ast->node_cond, GenMode_rval);
- printf(" pop rax\n");
- printf(" cmp rax, 0\n");
- printf(" je .Lelse%d\n", label);
- codegen_stmt(g, ast->node_then);
- printf(" jmp .Lend%d\n", label);
- printf(".Lelse%d:\n", label);
- if (ast->node_else) {
- codegen_stmt(g, ast->node_else);
- }
- printf(".Lend%d:\n", label);
-}
-
-void codegen_for_stmt(CodeGen* g, AstNode* ast) {
- int label = codegen_new_label(g);
- ++g->loop_labels;
- *g->loop_labels = label;
-
- if (ast->node_init) {
- codegen_expr(g, ast->node_init, GenMode_rval);
- printf(" pop rax\n");
- }
- printf(".Lbegin%d:\n", label);
- codegen_expr(g, ast->node_cond, GenMode_rval);
- printf(" pop rax\n");
- printf(" cmp rax, 0\n");
- printf(" je .Lend%d\n", label);
- codegen_stmt(g, ast->node_body);
- printf(".Lcontinue%d:\n", label);
- if (ast->node_update) {
- codegen_expr(g, ast->node_update, GenMode_rval);
- printf(" pop rax\n");
- }
- printf(" jmp .Lbegin%d\n", label);
- printf(".Lend%d:\n", label);
-
- --g->loop_labels;
-}
-
-void codegen_do_while_stmt(CodeGen* g, AstNode* ast) {
- int label = codegen_new_label(g);
- ++g->loop_labels;
- *g->loop_labels = label;
-
- printf(".Lbegin%d:\n", label);
- codegen_stmt(g, ast->node_body);
- printf(".Lcontinue%d:\n", label);
- codegen_expr(g, ast->node_cond, GenMode_rval);
- printf(" pop rax\n");
- printf(" cmp rax, 0\n");
- printf(" je .Lend%d\n", label);
- printf(" jmp .Lbegin%d\n", label);
- printf(".Lend%d:\n", label);
-
- --g->loop_labels;
-}
-
-void codegen_break_stmt(CodeGen* g, AstNode* ast) {
- int label = *g->loop_labels;
- printf(" jmp .Lend%d\n", label);
-}
-
-void codegen_continue_stmt(CodeGen* g, AstNode* ast) {
- int label = *g->loop_labels;
- printf(" jmp .Lcontinue%d\n", label);
-}
-
-void codegen_expr_stmt(CodeGen* g, AstNode* ast) {
- codegen_expr(g, ast->node_expr, GenMode_rval);
- // TODO: the expression on the stack can be more than 8 bytes.
- printf(" pop rax\n");
-}
-
-void codegen_var_decl(CodeGen* g, AstNode* ast) {
-}
-
-void codegen_nop(CodeGen* g, AstNode* ast) {
-}
-
-void codegen_block_stmt(CodeGen* g, AstNode* ast) {
- for (int i = 0; i < ast->node_len; ++i) {
- AstNode* stmt = ast->node_items + i;
- codegen_stmt(g, stmt);
- }
-}
-
-void codegen_stmt(CodeGen* g, AstNode* ast) {
- if (ast->kind == AstNodeKind_list) {
- codegen_block_stmt(g, ast);
- } else if (ast->kind == AstNodeKind_return_stmt) {
- codegen_return_stmt(g, ast);
- } else if (ast->kind == AstNodeKind_if_stmt) {
- codegen_if_stmt(g, ast);
- } else if (ast->kind == AstNodeKind_for_stmt) {
- codegen_for_stmt(g, ast);
- } else if (ast->kind == AstNodeKind_do_while_stmt) {
- codegen_do_while_stmt(g, ast);
- } else if (ast->kind == AstNodeKind_break_stmt) {
- codegen_break_stmt(g, ast);
- } else if (ast->kind == AstNodeKind_continue_stmt) {
- codegen_continue_stmt(g, ast);
- } else if (ast->kind == AstNodeKind_expr_stmt) {
- codegen_expr_stmt(g, ast);
- } else if (ast->kind == AstNodeKind_lvar_decl) {
- codegen_var_decl(g, ast);
- } else if (ast->kind == AstNodeKind_nop) {
- codegen_nop(g, ast);
- } else {
- unreachable();
- }
-}
-
-void codegen_func(CodeGen* g, AstNode* ast) {
- g->current_func = ast;
- printf("%s:\n", ast->name);
-
- codegen_func_prologue(g, ast);
- codegen_stmt(g, ast->node_body);
- if (strcmp(ast->name, "main") == 0) {
- // C99: 5.1.2.2.3
- printf(" mov rax, 0\n");
- }
- codegen_func_epilogue(g, ast);
-
- printf("\n");
- g->current_func = NULL;
-}
-
-void codegen(Program* prog) {
- CodeGen* g = codegen_new();
-
- printf(".intel_syntax noprefix\n\n");
-
- // For GNU ld:
- // https://sourceware.org/binutils/docs/ld/Options.html
- printf(".section .note.GNU-stack,\"\",@progbits\n\n");
-
- printf(".section .rodata\n\n");
- for (int i = 0; prog->str_literals[i]; ++i) {
- printf(".Lstr__%d:\n", i + 1);
- printf(" .string \"%s\"\n\n", prog->str_literals[i]);
- }
-
- printf(".data\n\n");
- for (int i = 0; i < prog->vars->node_len; ++i) {
- AstNode* var = prog->vars->node_items + i;
- if (var->node_expr) {
- if (var->ty->kind == TypeKind_char)
- printf(" %s: .byte %d\n", var->name, var->node_expr->node_int_value);
- else if (var->ty->kind == TypeKind_short)
- printf(" %s: .word %d\n", var->name, var->node_expr->node_int_value);
- else if (var->ty->kind == TypeKind_int)
- printf(" %s: .int %d\n", var->name, var->node_expr->node_int_value);
- else
- unimplemented();
- } else {
- printf(" %s: .zero %d\n", var->name, type_sizeof(var->ty));
- }
- }
-
- printf(".globl main\n\n");
-
- printf(".text\n\n");
- for (int i = 0; i < prog->funcs->node_len; ++i) {
- AstNode* func = prog->funcs->node_items + i;
- codegen_func(g, func);
- }
-}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-12-01 22:28:22 +0000