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Refactor assembler to use vec_t instead of buffer

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Clearer, precise and no double pointers.
This commit is contained in:
Aryadev Chavali
2024-12-19 08:45:47 +00:00
parent ffc8068a74
commit 7686c1043c
2 changed files with 48 additions and 51 deletions
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90
assembler.c
View File

@@ -17,22 +17,22 @@ struct Label
/* First, the functions to call external utilities (badly written, I know). They
* presume a filled asm_buffer. */
void asm_write(buffer_t **asm_buffer)
void asm_write(const char *asm_name, vec_t *asm_buffer)
{
FILE *fp = fopen(asm_buffer[0]->name, "w");
fwrite(asm_buffer[0]->data, asm_buffer[0]->size, 1, fp);
FILE *fp = fopen(asm_name, "w");
fwrite(asm_buffer->data, asm_buffer->size, 1, fp);
fclose(fp);
}
int asm_assemble(const char *srcname, const char *objname)
int asm_assemble(const char *asm_name, const char *objname)
{
#ifdef DEBUG
char *format_str = "yasm -f elf64 -g dwarf2 -o %s %s";
#else
char *format_str = "yasm -f elf64 -o %s %s";
#endif
char command[snprintf(NULL, 0, format_str, objname, srcname) + 1];
sprintf(command, format_str, objname, srcname);
char command[snprintf(NULL, 0, format_str, objname, asm_name) + 1];
sprintf(command, format_str, objname, asm_name);
return system(command);
}
@@ -44,45 +44,14 @@ int asm_link(const char *objname, const char *outname)
return system(command);
}
int asm_compile(buffer_t **asm_buffer, const char *objname, const char *outname)
int asm_compile(vec_t *asm_buffer, const char *asm_name, const char *objname,
const char *outname)
{
asm_write(asm_buffer);
asm_assemble(asm_buffer[0]->name, objname);
asm_write(asm_name, asm_buffer);
asm_assemble(asm_name, objname);
return asm_link(objname, outname);
}
void asm_setup_buffer(buffer_t **asm_buffer, const char *outname)
{
*asm_buffer = buffer_init_str(outname, NULL, 1024);
asm_buffer[0]->size = 0;
}
// Write the initial boilerplate of the assembly file
void asm_write_init(buffer_t **asm_buffer)
{
const char format_string[] = "section .bss\n"
" memory resb %d\n"
"section .text\n"
"global _start\n"
"_start:\n"
" mov r9, memory\n";
char initial_assembly[snprintf(NULL, 0, format_string, MEMORY_DEFAULT) + 1];
snprintf(initial_assembly, sizeof(initial_assembly), format_string,
MEMORY_DEFAULT);
buffer_append_bytes(asm_buffer, (u8 *)initial_assembly,
sizeof(initial_assembly) - 1);
}
// Write the exit code for the assembly file
void asm_write_exit(buffer_t **asm_buffer)
{
buffer_append_bytes(asm_buffer,
(u8 *)" mov rax, 60\n"
" mov rdi, 0\n"
" syscall\n",
37);
}
// A table which translates brainfuck operations into generic assembly code (I
// love C's array indexing)
static const struct
@@ -116,7 +85,13 @@ i64 get_abs_label(u64, struct Label *, u64);
// and next items in given pointers.
void ast_ref_to_asm_label(u64, struct Label *, u64, i64 *, i64 *);
void asm_translate_nodes(buffer_t **asm_buffer, struct PResult nodes,
// Write the initial boilerplate of the assembly file
void asm_write_init(vec_t *asm_buffer);
// Write the exit code boilerplate for the assembly file
void asm_write_exit(vec_t *asm_buffer);
void asm_translate_nodes(vec_t *asm_buffer, struct PResult nodes,
const char *src_name)
{
asm_write_init(asm_buffer);
@@ -175,14 +150,12 @@ void asm_translate_nodes(buffer_t **asm_buffer, struct PResult nodes,
1];
snprintf(formatted_string, sizeof(formatted_string), format_string,
current_label, next_label);
buffer_append_bytes(asm_buffer, (u8 *)formatted_string,
sizeof(formatted_string) - 1);
vec_append(asm_buffer, formatted_string, sizeof(formatted_string) - 1);
}
else
{
// I love tables so goddamn much
buffer_append_bytes(asm_buffer, (u8 *)table[node.type].str,
table[node.type].len);
vec_append(asm_buffer, table[node.type].str, table[node.type].len);
}
}
asm_write_exit(asm_buffer);
@@ -206,3 +179,28 @@ void ast_ref_to_asm_label(u64 ref, struct Label *labels, u64 size, i64 *cur,
return;
*next = get_abs_label(labels[*cur].next, labels, size);
}
// Write the initial boilerplate of the assembly file
void asm_write_init(vec_t *asm_buffer)
{
const char format_string[] = "section .bss\n"
" memory resb %d\n"
"section .text\n"
"global _start\n"
"_start:\n"
" mov r9, memory\n";
char initial_assembly[snprintf(NULL, 0, format_string, MEMORY_DEFAULT) + 1];
snprintf(initial_assembly, sizeof(initial_assembly), format_string,
MEMORY_DEFAULT);
vec_append(asm_buffer, initial_assembly, sizeof(initial_assembly) - 1);
}
// Write the exit code for the assembly file
void asm_write_exit(vec_t *asm_buffer)
{
vec_append(asm_buffer,
" mov rax, 60\n"
" mov rdi, 0\n"
" syscall\n",
37);
}

9
assembler.h
View File

@@ -4,14 +4,13 @@
#include "./lib.h"
#include "./parser.h"
void asm_setup_buffer(buffer_t **asm_buffer, const char *outname);
void asm_translate_nodes(buffer_t **asm_buffer, struct PResult nodes,
void asm_translate_nodes(vec_t *asm_buffer, struct PResult nodes,
const char *src_name);
void asm_write(buffer_t **asm_buffer);
int asm_assemble(const char *srcname, const char *objname);
void asm_write(const char *asm_name, vec_t *asm_buffer);
int asm_assemble(const char *asm_name, const char *objname);
int asm_link(const char *objname, const char *outname);
int asm_compile(buffer_t **asm_buffer, const char *objname,
int asm_compile(vec_t *asm_buffer, const char *asm_name, const char *objname,
const char *outname);
#endif