refactor masm to add codegen step

1 files changed, 118 insertions, 0 deletions

diff --git a/masm/gen.h b/masm/gen.h
new file mode 100644
index 0000000..19f575c
--- /dev/null
+++ b/masm/gen.h
@@ -0,0 +1,118 @@
+/* Copyright (c) 2024 Freya Murphy */
+
+#ifndef __GEN_H__
+#define __GEN_H__
+
+#include <mlimits.h>
+#include <mips32.h>
+#include <stdint.h>
+
+#include "parse.h"
+#include "tab.h"
+
+// predefine
+struct generator;
+
+///
+/// a section
+///
+struct section {
+	// name
+	struct string name;
+
+	// alignment
+	size_t align;
+
+	// data
+	char *data;
+	size_t len;
+	size_t size;
+
+	// permissions
+	bool read;
+	bool write;
+	bool execute;
+
+	/// reference table
+	struct reference_table reftab;
+};
+
+void section_free(struct section *section);
+
+///
+/// instruction generation state
+///
+
+struct gen_ins_state {
+	// rd,rst,rt
+	enum mips32_register rd;
+	enum mips32_register rs;
+	enum mips32_register rt;
+
+	// immd
+	uint16_t immd;
+
+	// offset(base)
+	uint16_t offset;
+	enum mips32_register base;
+
+	// target
+	uint32_t target;
+
+	// current referencd label
+	struct string *label;
+};
+
+///
+/// grammer type
+///
+
+enum grammer_type {
+	GMR_RD,
+	GMR_RS,
+	GMR_RT,
+	GMR_IMMD,
+	GMR_OFFSET,
+	GMR_OFFSET_BASE,
+	GMR_TARGET,
+	GMR_HI,
+	GMR_LO,
+};
+
+///
+/// generates assembley
+/// from a parser stream
+///
+struct generator {
+	struct parser parser;
+
+	// current instruction table
+	size_t instructions_len;
+	union mips32_instruction *instructions;
+
+	// current grammer table
+	size_t grammers_len;
+	struct mips32_grammer *grammers;
+
+	// segments
+	size_t sections_len;
+	size_t sections_size;
+	struct section *sections;
+
+	// current section
+	struct section *current;
+
+	// symbol table
+	struct symbol_table symtab;
+};
+
+/* generate the input as mips32r6 */
+int generate_mips32r6(struct generator *gen);
+
+/* initalize a generator */
+int generator_init(const char *file, struct generator *gen);
+
+/* free a generator */
+void generator_free(struct generator *gen);
+
+#endif /* __GEN_H__ */