core: Add initial codegen sources

Signed-off-by: Ian Moffett <ian@mirocom.org>

Makefile

@@ -1,3 +1,6 @@
+ARCH_TARGET = x86_64
+BACKEND = backend/$(ARCH_TARGET).c
+
 CFILES = $(shell find core/ -name "*.c")
 OFILES = $(CFILES:.c=.o)
 DFILES = $(CFILES:.c=.d)
@@ -7,7 +10,7 @@ CFLAGS = -Wall -pedantic -Iinc/ -MMD
 
 .PHONY: all
 all: $(OFILES)
-	$(CC) $(OFILES) -o rifle
+	$(CC) $(BACKEND) $(CFLAGS) $(OFILES) -o rifle
 
 -include $(DFILES)
 %.o: %.c

backend/x86_64.c

@@ -0,0 +1,19 @@
+#include <stdio.h>
+#include "rifle/mu.h"
+
+int
+mu_gen_label(struct rifle_state *state, const char *name)
+{
+    if (state == NULL || name == NULL) {
+        return -1;
+    }
+
+    fprintf(
+        state->out_fp,
+        "%s:\n",
+        name
+    );
+
+    return 0;
+}
+

core/codegen.c

@@ -0,0 +1,42 @@
+#include <stdint.h>
+#include <stddef.h>
+#include "rifle/codegen.h"
+#include "rifle/trace.h"
+#include "rifle/mu.h"
+
+static int
+resolve_func(struct rifle_state *state, struct ast_node *root)
+{
+    struct symbol *symbol;
+
+    if (state == NULL || root == NULL) {
+        return -1;
+    }
+
+    if ((symbol = root->symbol) == NULL) {
+        trace_error(state, "internal: no symbol associated with func node\n");
+        return -1;
+    }
+
+    return mu_gen_label(state, symbol->name);
+}
+
+int
+cg_resolve_node(struct rifle_state *state, struct ast_node *root)
+{
+    if (state == NULL || root == NULL) {
+        return -1;
+    }
+
+    switch (root->type) {
+    case AST_FUNC:
+        if (resolve_func(state, root) < 0) {
+            return -1;
+        }
+
+        break;
+    default:
+        trace_error(state, "unknown ast node %d\n", root->type);
+        break;
+    }
+}

core/parser.c

@@ -9,6 +9,7 @@
 #include "rifle/types.h"
 #include "rifle/ast.h"
 #include "rifle/scope.h"
+#include "rifle/codegen.h"
 
 /* Symbolic token */
 #define symtok(tok) \
@@ -438,6 +439,8 @@ parse_func(struct rifle_state *state, struct token *tok, struct ast_node **res)
         return -1;
     }
 
+    root->symbol = symbol;
+
     /* EXPECT '(' */
     if (parse_expect(state, TT_LPAREN, tok) < 0) {
         return -1;
@@ -468,6 +471,7 @@ parse_func(struct rifle_state *state, struct token *tok, struct ast_node **res)
         return -1;
     }
 
+    *res = root;
     return 0;
 }
 
@@ -501,7 +505,7 @@ static int
 parse_begin(struct rifle_state *state)
 {
     struct token tok;
-    struct ast_node *root;
+    struct ast_node *root = NULL;
 
     while (parse_scan(state, &tok) == 0) {
         switch (tok.type) {
@@ -523,6 +527,11 @@ parse_begin(struct rifle_state *state)
         }
     }
 
+    if (root != NULL) {
+        if (cg_resolve_node(state, root) < 0)
+            return -1;
+    }
+
     return 0;
 }
 

core/state.c

@@ -16,19 +16,28 @@ rifle_state_init(struct rifle_state *state, const char *in_path)
         return -1;
     }
 
+    state->out_fp = fopen(ASMOUT, "w");
+    if (state->out_fp == NULL) {
+        close(state->in_fd);
+        return -1;
+    }
+
     if (ptrbox_init(&state->ptrbox) < 0) {
         close(state->in_fd);
+        fclose(state->out_fp);
         return -1;
     }
 
     if (symbol_table_init(&state->symtab) < 0) {
         close(state->in_fd);
+        fclose(state->out_fp);
         ptrbox_destroy(&state->ptrbox);
         return -1;
     }
 
     if (tokbuf_init(&state->tokbuf) < 0) {
         ptrbox_destroy(&state->ptrbox);
+        fclose(state->out_fp);
         symbol_table_destroy(&state->symtab);
         close(state->in_fd);
         return -1;
@@ -49,4 +58,5 @@ rifle_state_destroy(struct rifle_state *state)
     state->in_fd = -1;
     tokbuf_destroy(&state->tokbuf);
     symbol_table_destroy(&state->symtab);
+    fclose(state->out_fp);
 }

inc/rifle/ast.h

@@ -24,12 +24,14 @@ typedef enum {
  * @dtype:  Data type
  * @left:   Left leaf
  * @right:  Right leaf
+ * @symbol: Symbol associated with node
  */
 struct ast_node {
    ast_type_t type;
    struct data_type dtype;
    struct ast_node *left;
    struct ast_node *right;
+   struct symbol *symbol;
 };
 
 /*

inc/rifle/codegen.h

@@ -0,0 +1,20 @@
+#ifndef RIFLE_CODEGEN_H
+#define RIFLE_CODEGEN_H 1
+
+#include <stdint.h>
+#include <stddef.h>
+#include "rifle/ast.h"
+#include "rifle/state.h"
+
+/*
+ * Resolve a node and generate assembly code as an
+ * output.
+ *
+ * @state: Compiler state
+ * @root: Root input node to resolve
+ *
+ * Returns zero on success
+ */
+int cg_resolve_node(struct rifle_state *state, struct ast_node *root);
+
+#endif  /* !RIFLE_CODEGEN_H */

inc/rifle/mu.h

@@ -0,0 +1,18 @@
+#ifndef RIFLE_MU_H
+#define RIFLE_MU_H 1
+
+#include <stdint.h>
+#include <stddef.h>
+#include "rifle/state.h"
+
+/*
+ * Generate a named label
+ *
+ * @state: Compiler state
+ * @name:  Name of label to generate
+ *
+ * Returns zero on success
+ */
+int mu_gen_label(struct rifle_state *state, const char *name);
+
+#endif  /* !RIFLE_MU_H */

inc/rifle/state.h

@@ -2,6 +2,7 @@
 #define RIFLE_STATE_H 1
 
 #include <stdint.h>
+#include <stdio.h>
 #include <stddef.h>
 #include "rifle/tokbuf.h"
 #include "rifle/ptrbox.h"
@@ -11,10 +12,14 @@
 /* Maximum scope depth */
 #define SCOPE_STACK_MAX 8
 
+/* Default assembly output path */
+#define ASMOUT "rifleout.asm"
+
 /*
  * Represents the compiler state
  *
  * @in_fd: Input file descriptor
+ * @out_fp: Output file
  * @line_num: Current line number
  * @pass_num: Current pass
  * @tokbuf: Global token buffer
@@ -27,6 +32,7 @@
  */
 struct rifle_state {
     int in_fd;
+    FILE *out_fp;
     size_t line_num;
     size_t pass_num;
     struct tokbuf tokbuf;