Refactor buildvm symbol generation.

Fixes Windows and OSX builds with LUAJIT_DISABLE_JIT.

src/buildvm.c

@@ -101,6 +101,33 @@ static void emit_raw(BuildCtx *ctx)
 
 /* -- Build machine code -------------------------------------------------- */
 
+static const char *sym_decorate(BuildCtx *ctx,
+				const char *prefix, const char *suffix)
+{
+  char name[256];
+  char *p;
+#if LJ_64
+  const char *symprefix = ctx->mode == BUILD_machasm ? "_" : "";
+#else
+  const char *symprefix = ctx->mode != BUILD_elfasm ? "_" : "";
+#endif
+  sprintf(name, "%s%s%s", symprefix, prefix, suffix);
+  p = strchr(name, '@');
+  if (p) {
+    if (!LJ_64 && (ctx->mode == BUILD_coffasm || ctx->mode == BUILD_peobj))
+      name[0] = '@';
+    else
+      *p = '\0';
+  }
+  p = (char *)malloc(strlen(name)+1);  /* MSVC doesn't like strdup. */
+  strcpy(p, name);
+  return p;
+}
+
+#define NRELOCSYM	(sizeof(extnames)/sizeof(extnames[0])-1)
+
+static int relocmap[NRELOCSYM];
+
 /* Collect external relocations. */
 static int collect_reloc(BuildCtx *ctx, uint8_t *addr, int idx, int type)
 {
@@ -108,32 +135,38 @@ static int collect_reloc(BuildCtx *ctx, uint8_t *addr, int idx, int type)
     fprintf(stderr, "Error: too many relocations, increase BUILD_MAX_RELOC.\n");
     exit(1);
   }
+  if (relocmap[idx] < 0) {
+    relocmap[idx] = ctx->nrelocsym;
+    ctx->relocsym[ctx->nrelocsym] = sym_decorate(ctx, "", extnames[idx]);
+    ctx->nrelocsym++;
+  }
   ctx->reloc[ctx->nreloc].ofs = (int32_t)(addr - ctx->code);
-  ctx->reloc[ctx->nreloc].sym = idx;
+  ctx->reloc[ctx->nreloc].sym = relocmap[idx];
   ctx->reloc[ctx->nreloc].type = type;
   ctx->nreloc++;
   return 0;  /* Encode symbol offset of 0. */
 }
 
 /* Naive insertion sort. Performance doesn't matter here. */
-static void perm_insert(int *perm, int32_t *ofs, int i)
+static void sym_insert(BuildCtx *ctx, int32_t ofs,
+		       const char *prefix, const char *suffix)
 {
-  perm[i] = i;
+  ptrdiff_t i = ctx->nsym++;
   while (i > 0) {
-    int a = perm[i-1];
-    int b = perm[i];
-    if (ofs[a] <= ofs[b]) break;
-    perm[i] = a;
-    perm[i-1] = b;
+    if (ctx->sym[i-1].ofs <= ofs)
+      break;
+    ctx->sym[i] = ctx->sym[i-1];
     i--;
   }
+  ctx->sym[i].ofs = ofs;
+  ctx->sym[i].name = sym_decorate(ctx, prefix, suffix);
 }
 
 /* Build the machine code. */
 static int build_code(BuildCtx *ctx)
 {
   int status;
-  int i, j;
+  int i;
 
   /* Initialize DynASM structures. */
   ctx->nglob = GLOB__MAX;
@@ -141,8 +174,10 @@ static int build_code(BuildCtx *ctx)
   memset(ctx->glob, 0, ctx->nglob*sizeof(void *));
   ctx->nreloc = 0;
 
-  ctx->extnames = extnames;
   ctx->globnames = globnames;
+  ctx->relocsym = (const char **)malloc(NRELOCSYM*sizeof(const char *));
+  ctx->nrelocsym = 0;
+  for (i = 0; i < (int)NRELOCSYM; i++) relocmap[i] = -1;
 
   ctx->dasm_ident = DASM_IDENT;
   ctx->dasm_arch = DASM_ARCH;
@@ -160,37 +195,41 @@ static int build_code(BuildCtx *ctx)
   ctx->code = (uint8_t *)malloc(ctx->codesz);
   if ((status = dasm_encode(Dst, (void *)ctx->code))) return status;
 
-  /* Allocate the symbol offset and permutation tables. */
-  ctx->nsym = ctx->npc + ctx->nglob;
-  ctx->perm = (int *)malloc((ctx->nsym+1)*sizeof(int *));
-  ctx->sym_ofs = (int32_t *)malloc((ctx->nsym+1)*sizeof(int32_t));
+  /* Allocate symbol table and bytecode offsets. */
+  ctx->beginsym = sym_decorate(ctx, "", LABEL_PREFIX "vm_asm_begin");
+  ctx->sym = (BuildSym *)malloc((ctx->npc+ctx->nglob+1)*sizeof(BuildSym));
+  ctx->nsym = 0;
+  ctx->bc_ofs = (int32_t *)malloc(ctx->npc*sizeof(int32_t));
 
   /* Collect the opcodes (PC labels). */
   for (i = 0; i < ctx->npc; i++) {
-    int32_t n = dasm_getpclabel(Dst, i);
-    if (n < 0) return 0x22000000|i;
-    ctx->sym_ofs[i] = n;
-    perm_insert(ctx->perm, ctx->sym_ofs, i);
+    int32_t ofs = dasm_getpclabel(Dst, i);
+    if (ofs < 0) return 0x22000000|i;
+    ctx->bc_ofs[i] = ofs;
+#if !LJ_HASJIT
+    if (!(i == BC_JFORI || i == BC_JFORL || i == BC_JITERL || i == BC_JLOOP ||
+	  i == BC_IFORL || i == BC_IITERL || i == BC_ILOOP))
+#endif
+      sym_insert(ctx, ofs, LABEL_PREFIX_BC, bc_names[i]);
   }
 
   /* Collect the globals (named labels). */
-  for (j = 0; j < ctx->nglob; j++, i++) {
-    const char *gl = globnames[j];
+  for (i = 0; i < ctx->nglob; i++) {
+    const char *gl = globnames[i];
     int len = (int)strlen(gl);
-    if (!ctx->glob[j]) {
+    if (!ctx->glob[i]) {
       fprintf(stderr, "Error: undefined global %s\n", gl);
       exit(2);
     }
-    if (len >= 2 && gl[len-2] == '_' && gl[len-1] == 'Z')
-      ctx->sym_ofs[i] = -1;  /* Skip the _Z symbols. */
-    else
-      ctx->sym_ofs[i] = (int32_t)((uint8_t *)(ctx->glob[j]) - ctx->code);
-    perm_insert(ctx->perm, ctx->sym_ofs, i);
+    /* Skip the _Z symbols. */
+    if (!(len >= 2 && gl[len-2] == '_' && gl[len-1] == 'Z'))
+      sym_insert(ctx, (int32_t)((uint8_t *)(ctx->glob[i]) - ctx->code),
+		 LABEL_PREFIX, globnames[i]);
   }
 
   /* Close the address range. */
-  ctx->sym_ofs[i] = (int32_t)ctx->codesz;
-  perm_insert(ctx->perm, ctx->sym_ofs, i);
+  sym_insert(ctx, (int32_t)ctx->codesz, "", "");
+  ctx->nsym--;
 
   dasm_free(Dst);
 
@@ -260,7 +299,7 @@ static void emit_bcdef(BuildCtx *ctx)
   for (i = 0; i < ctx->npc; i++) {
     if (i != 0)
       fprintf(ctx->fp, ",\n");
-    fprintf(ctx->fp, "%d", ctx->sym_ofs[i]);
+    fprintf(ctx->fp, "%d", ctx->bc_ofs[i]);
   }
 }