core+backend: Add support for label sections

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

backend/x86_64.c

@@ -2,10 +2,15 @@
 #include "rifle/mu.h"
 
 #define retreg(msize)        \
-    (msize >= MSIZE_MAX)    \
+    ((msize) >= MSIZE_MAX)   \
         ? "bad"              \
         : rettab[(msize)]
 
+#define secname(secid)       \
+    ((secid) >= SECTION_MAX) \
+        ? "bad"              \
+        : secttab[(secid)]
+
 /* Size to return register table */
 static const char *rettab[] = {
     [MSIZE_BYTE]  = "al",
@@ -14,8 +19,35 @@ static const char *rettab[] = {
     [MSIZE_QWORD] = "rax"
 };
 
+/* Section ID to name table */
+static const char *secttab[] = {
+    [SECTION_NONE] = ".none",
+    [SECTION_TEXT] = ".text",
+    [SECTION_DATA] = ".data",
+    [SECTION_RODATA] = ".rodata",
+    [SECTION_BSS] = ".bss"
+};
+
+static inline void
+force_section(struct rifle_state *state, section_t section)
+{
+    if (state == NULL) {
+        return;
+    }
+
+    if (state->section != section) {
+        state->section = section;
+        fprintf(
+            state->out_fp,
+            "[section %s]\n",
+            secname(section)
+        );
+    }
+}
+
 int
-mu_gen_label(struct rifle_state *state, const char *name, bool global)
+mu_gen_label(struct rifle_state *state, section_t section, const char *name,
+    bool global)
 {
     if (state == NULL || name == NULL) {
         return -1;
@@ -29,6 +61,7 @@ mu_gen_label(struct rifle_state *state, const char *name, bool global)
         );
     }
 
+    force_section(state, section);
     fprintf(
         state->out_fp,
         "%s:\n",

core/codegen.c

@@ -22,7 +22,7 @@ resolve_func(struct rifle_state *state, struct ast_node *root)
         return -1;
     }
 
-    return mu_gen_label(state, symbol->name, symbol->pub);
+    return mu_gen_label(state, SECTION_TEXT, symbol->name, symbol->pub);
 }
 
 static int
@@ -81,10 +81,10 @@ resolve_loop(struct rifle_state *state, struct ast_node *root)
         mu_gen_blab(state, label);
 
         snprintf(label, sizeof(label), "L.%zu.1", state->loop_count - 1);
-        mu_gen_label(state, label, false);
+        mu_gen_label(state, SECTION_TEXT, label, false);
     } else {
         snprintf(label, sizeof(label), "L.%zu", state->loop_count++);
-        mu_gen_label(state, label, false);
+        mu_gen_label(state, SECTION_TEXT, label, false);
     }
 
     return 0;

inc/rifle/mu.h

@@ -46,12 +46,16 @@ type_to_msize(data_type_t type)
  * Generate a named label
  *
  * @state: Compiler state
+ * @section: Section to place label within
  * @name:  Name of label to generate
  * @global: If true, symbol is to be marked global
  *
  * Returns zero on success
  */
-int mu_gen_label(struct rifle_state *state, const char *name, bool global);
+int mu_gen_label(
+    struct rifle_state *state, section_t section,
+    const char *name, bool global
+);
 
 /*
  * Generate a register fill corresponding to the platform return

inc/rifle/state.h

@@ -15,6 +15,18 @@
 /* Default assembly output path */
 #define ASMOUT "rifleout.asm"
 
+/*
+ * Represents valid section types
+ */
+typedef enum {
+    SECTION_NONE,
+    SECTION_TEXT,
+    SECTION_DATA,
+    SECTION_RODATA,
+    SECTION_BSS,
+    SECTION_MAX
+} section_t;
+
 /*
  * Represents the compiler state
  *
@@ -31,6 +43,7 @@
  * @scope_depth: How deep in scope we are
  * @have_ret: If set, function has return statement
  * @scope_stack: Used to track scopes
+ * @section: Current section
  * @cur_func: Current function
  */
 struct rifle_state {
@@ -47,6 +60,7 @@ struct rifle_state {
     uint8_t scope_depth;
     uint8_t have_ret : 1;
     tt_t scope_stack[SCOPE_STACK_MAX];
+    section_t section;
     struct symbol *cur_func;
 };