labels: add a subsection field available for backend use

Allow the subsection to store a subsection value directly in the
label, rather than having to do strange encoding hacks.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

5 files changed, 34 insertions, 17 deletions

diff --git a/asm/labels.c b/asm/labels.c
index 94a57ac2..eec5a844 100644
--- a/asm/labels.c
+++ b/asm/labels.c
@@ -92,6 +92,7 @@ static const char * const types[] =
 union label {                   /* actual label structures */
     struct {
         int32_t segment;
+        int32_t subsection;     /* Available for ofmt->herelabel() */
         int64_t offset;
         int64_t size;
         char *label, *mangled, *special;
@@ -231,6 +232,7 @@ static union label *find_label(const char *label, bool create, bool *created)
     nasm_zero(*lfree);
     lfree->admin.movingon = BOGUS_VALUE;
     lfree->defn.label     = perm_copy(label);
+    lfree->defn.subsection = NO_SEG;
     if (label_str)
         nasm_free(label_str);
 
@@ -321,7 +323,7 @@ static const char *mangle_label_name(union label *lptr)
 }
 
 static void
-handle_herelabel(const union label *lptr, int32_t *segment, int64_t *offset)
+handle_herelabel(union label *lptr, int32_t *segment, int64_t *offset)
 {
     int32_t oldseg;
 
@@ -338,7 +340,8 @@ handle_herelabel(const union label *lptr, int32_t *segment, int64_t *offset)
         int32_t newseg;
 
         nasm_assert(lptr->defn.mangled);
-        newseg = ofmt->herelabel(lptr->defn.mangled, lptr->defn.type, oldseg);
+        newseg = ofmt->herelabel(lptr->defn.mangled, lptr->defn.type,
+                                 oldseg, &lptr->defn.subsection);
         if (likely(newseg == oldseg))
             return;
 
diff --git a/asm/nasm.c b/asm/nasm.c
index 4e922b4a..94bbc6b2 100644
--- a/asm/nasm.c
+++ b/asm/nasm.c
@@ -91,6 +91,7 @@ static const char *debug_format;
 # define ABORT_ON_PANIC 0
 #endif
 static bool abort_on_panic = ABORT_ON_PANIC;
+static bool keep_all;
 
 bool tasm_compatible_mode = false;
 int pass0, passn;
@@ -540,7 +541,7 @@ int main(int argc, char **argv)
             preproc->cleanup(0);
             if (ofile)
                 fclose(ofile);
-            if (ofile && terminate_after_phase)
+            if (ofile && terminate_after_phase && !keep_all)
                 remove(outname);
             ofile = NULL;
     }
@@ -576,7 +577,7 @@ int main(int argc, char **argv)
 
         if (ofile) {
             fclose(ofile);
-            if (terminate_after_phase)
+            if (terminate_after_phase && !keep_all)
                 remove(outname);
             ofile = NULL;
         }
@@ -786,7 +787,8 @@ enum text_options {
     OPT_INCLUDE,
     OPT_PRAGMA,
     OPT_BEFORE,
-    OPT_LIMIT
+    OPT_LIMIT,
+    OPT_KEEP_ALL
 };
 struct textargs {
     const char *label;
@@ -809,6 +811,7 @@ static const struct textargs textopts[] = {
     {"pragma",   OPT_PRAGMA,  true, 0},
     {"before",   OPT_BEFORE,  true, 0},
     {"limit-",   OPT_LIMIT,   true, 0},
+    {"keep-all", OPT_KEEP_ALL, false, 0},
     {NULL, OPT_BOGUS, false, 0}
 };
 
@@ -1155,6 +1158,9 @@ static bool process_arg(char *p, char *q, int pass)
                     if (pass == 2)
                         nasm_set_limit(p+olen, param);
                     break;
+                case OPT_KEEP_ALL:
+                    keep_all = true;
+                    break;
                 case OPT_HELP:
                     help(0);
                     exit(0);
@@ -1400,7 +1406,7 @@ static void assemble_file(const char *fname, StrList **depend_ptr)
         cpu = cmd_cpu;
         if (pass0 == 2) {
 	    lfmt->init(listname);
-        } else if (passn == 1 && listname) {
+        } else if (passn == 1 && listname && !keep_all) {
             /* Remove the list file in case we die before the output pass */
             remove(listname);
         }
@@ -1859,7 +1865,8 @@ static void nasm_verror_common(int severity, const char *fmt, va_list args)
     case ERR_FATAL:
         if (ofile) {
             fclose(ofile);
-            remove(outname);
+            if (!keep_all)
+                remove(outname);
             ofile = NULL;
         }
         if (want_usage)
@@ -1874,7 +1881,8 @@ static void nasm_verror_common(int severity, const char *fmt, va_list args)
 
         if (ofile) {
             fclose(ofile);
-            remove(outname);
+            if (!keep_all)
+                remove(outname);
             ofile = NULL;
         }
         exit(3);
diff --git a/include/nasm.h b/include/nasm.h
index c1ecf8a1..a801da46 100644
--- a/include/nasm.h
+++ b/include/nasm.h
@@ -915,8 +915,11 @@ struct ofmt {
      * This is *only* called if the symbol defined is at the
      * current offset, i.e. "foo:" or "foo equ $".
      * The offset isn't passed; and may not be stable at this point.
+     * The subsection number is a field available for use by the
+     * backend. It is initialized to NO_SEG.
      */
-    int32_t (*herelabel)(const char *name, enum label_type type, int32_t seg);
+    int32_t (*herelabel)(const char *name, enum label_type type,
+                         int32_t seg, int32_t *subsection);
 
     /*
      * This procedure is called to modify section alignment,
diff --git a/output/outdbg.c b/output/outdbg.c
index 4d41d4db..84cccf73 100644
--- a/output/outdbg.c
+++ b/output/outdbg.c
@@ -136,15 +136,17 @@ static int32_t dbg_section_names(char *name, int pass, int *bits)
 }
 
 static int32_t dbg_herelabel(const char *name, enum label_type type,
-                             int32_t seg)
+                             int32_t oldseg, int32_t *subsection)
 {
-    int32_t newseg = seg;
-    
-    if (subsections_via_symbols && type != LBL_LOCAL)
-        newseg += 0x10000;
+    int32_t newseg = oldseg;
     
+    if (subsections_via_symbols && type != LBL_LOCAL) {
+        newseg = *subsection;
+        if (newseg == NO_SEG)
+            newseg = *subsection = seg_alloc();
+    }
     fprintf(ofile, "herelabel %s type %d (seg %08x) -> %08x\n",
-            name, type, seg, newseg);
+            name, type, oldseg, newseg);
 
     return newseg;
 }
diff --git a/output/outmacho.c b/output/outmacho.c
index ed1366b3..e4aa8000 100644
--- a/output/outmacho.c
+++ b/output/outmacho.c
@@ -1003,10 +1003,11 @@ static int32_t macho_section(char *name, int pass, int *bits)
 }
 
 static int32_t macho_herelabel(const char *name, enum label_type type,
-			       int32_t section)
+			       int32_t section, int32_t *subsection)
 {
     struct section *s;
     (void)name;
+    (void)subsection;
     
     if (!(head_flags & MH_SUBSECTIONS_VIA_SYMBOLS))
 	return section;
@@ -1014,7 +1015,7 @@ static int32_t macho_herelabel(const char *name, enum label_type type,
     /* No subsection only for local labels */
     if (type == LBL_LOCAL)
 	return section;
-    
+
     s = get_section_by_index(section);
     if (!s)
 	return section;