1 files changed, 59 insertions, 80 deletions

diff --git a/src/lj_bcread.c b/src/lj_bcread.c
index 2b5ba855..9f025500 100644
--- a/src/lj_bcread.c
+++ b/src/lj_bcread.c
@@ -9,6 +9,7 @@
 #include "lj_obj.h"
 #include "lj_gc.h"
 #include "lj_err.h"
+#include "lj_buf.h"
 #include "lj_str.h"
 #include "lj_tab.h"
 #include "lj_bc.h"
@@ -20,6 +21,7 @@
 #include "lj_lex.h"
 #include "lj_bcdump.h"
 #include "lj_state.h"
+#include "lj_strfmt.h"
 
 /* Reuse some lexer fields for our own purposes. */
 #define bcread_flags(ls)        ls->level
@@ -38,84 +40,73 @@ static LJ_NOINLINE void bcread_error(LexState *ls, ErrMsg em)
   const char *name = ls->chunkarg;
   if (*name == BCDUMP_HEAD1) name = "(binary)";
   else if (*name == '@' || *name == '=') name++;
-  lj_str_pushf(L, "%s: %s", name, err2msg(em));
+  lj_strfmt_pushf(L, "%s: %s", name, err2msg(em));
   lj_err_throw(L, LUA_ERRSYNTAX);
 }
 
-/* Resize input buffer. */
-static void bcread_resize(LexState *ls, MSize len)
-{
-  if (ls->sb.sz < len) {
-    MSize sz = ls->sb.sz * 2;
-    while (len > sz) sz = sz * 2;
-    lj_str_resizebuf(ls->L, &ls->sb, sz);
-    /* Caveat: this may change ls->sb.buf which may affect ls->p. */
-  }
-}
-
-/* Refill buffer if needed. */
+/* Refill buffer. */
 static LJ_NOINLINE void bcread_fill(LexState *ls, MSize len, int need)
 {
   lua_assert(len != 0);
-  if (len > LJ_MAX_MEM || ls->current < 0)
+  if (len > LJ_MAX_MEM || ls->c < 0)
     bcread_error(ls, LJ_ERR_BCBAD);
   do {
     const char *buf;
-    size_t size;
-    if (ls->n) {  /* Copy remainder to buffer. */
-      if (ls->sb.n) {  /* Move down in buffer. */
-        lua_assert(ls->p + ls->n == ls->sb.buf + ls->sb.n);
-        if (ls->n != ls->sb.n)
-          memmove(ls->sb.buf, ls->p, ls->n);
+    size_t sz;
+    char *p = sbufB(&ls->sb);
+    MSize n = (MSize)(ls->pe - ls->p);
+    if (n) {  /* Copy remainder to buffer. */
+      if (sbuflen(&ls->sb)) {  /* Move down in buffer. */
+        lua_assert(ls->pe == sbufP(&ls->sb));
+        if (ls->p != p) memmove(p, ls->p, n);
       } else {  /* Copy from buffer provided by reader. */
-        bcread_resize(ls, len);
-        memcpy(ls->sb.buf, ls->p, ls->n);
+        p = lj_buf_need(&ls->sb, len);
+        memcpy(p, ls->p, n);
       }
-      ls->p = ls->sb.buf;
+      ls->p = p;
+      ls->pe = p + n;
     }
-    ls->sb.n = ls->n;
-    buf = ls->rfunc(ls->L, ls->rdata, &size);  /* Get more data from reader. */
-    if (buf == NULL || size == 0) {  /* EOF? */
+    setsbufP(&ls->sb, p + n);
+    buf = ls->rfunc(ls->L, ls->rdata, &sz);  /* Get more data from reader. */
+    if (buf == NULL || sz == 0) {  /* EOF? */
       if (need) bcread_error(ls, LJ_ERR_BCBAD);
-      ls->current = -1;  /* Only bad if we get called again. */
+      ls->c = -1;  /* Only bad if we get called again. */
       break;
     }
-    if (ls->sb.n) {  /* Append to buffer. */
-      MSize n = ls->sb.n + (MSize)size;
-      bcread_resize(ls, n < len ? len : n);
-      memcpy(ls->sb.buf + ls->sb.n, buf, size);
-      ls->n = ls->sb.n = n;
-      ls->p = ls->sb.buf;
+    if (n) {  /* Append to buffer. */
+      n += (MSize)sz;
+      p = lj_buf_need(&ls->sb, n < len ? len : n);
+      memcpy(sbufP(&ls->sb), buf, sz);
+      setsbufP(&ls->sb, p + n);
+      ls->p = p;
+      ls->pe = p + n;
     } else {  /* Return buffer provided by reader. */
-      ls->n = (MSize)size;
       ls->p = buf;
+      ls->pe = buf + sz;
     }
-  } while (ls->n < len);
+  } while (ls->p + len > ls->pe);
 }
 
 /* Need a certain number of bytes. */
 static LJ_AINLINE void bcread_need(LexState *ls, MSize len)
 {
-  if (LJ_UNLIKELY(ls->n < len))
+  if (LJ_UNLIKELY(ls->p + len > ls->pe))
     bcread_fill(ls, len, 1);
 }
 
 /* Want to read up to a certain number of bytes, but may need less. */
 static LJ_AINLINE void bcread_want(LexState *ls, MSize len)
 {
-  if (LJ_UNLIKELY(ls->n < len))
+  if (LJ_UNLIKELY(ls->p + len > ls->pe))
     bcread_fill(ls, len, 0);
 }
 
-#define bcread_dec(ls)          check_exp(ls->n > 0, ls->n--)
-#define bcread_consume(ls, len) check_exp(ls->n >= (len), ls->n -= (len))
-
 /* Return memory block from buffer. */
-static uint8_t *bcread_mem(LexState *ls, MSize len)
+static LJ_AINLINE uint8_t *bcread_mem(LexState *ls, MSize len)
 {
   uint8_t *p = (uint8_t *)ls->p;
-  bcread_consume(ls, len);
-  ls->p = (char *)p + len;
+  ls->p += len;
+  lua_assert(ls->p <= ls->pe);
   return p;
 }
 
@@ -128,25 +119,15 @@ static void bcread_block(LexState *ls, void *q, MSize len)
 /* Read byte from buffer. */
 static LJ_AINLINE uint32_t bcread_byte(LexState *ls)
 {
-  bcread_dec(ls);
+  lua_assert(ls->p < ls->pe);
   return (uint32_t)(uint8_t)*ls->p++;
 }
 
 /* Read ULEB128 value from buffer. */
-static uint32_t bcread_uleb128(LexState *ls)
+static LJ_AINLINE uint32_t bcread_uleb128(LexState *ls)
 {
-  const uint8_t *p = (const uint8_t *)ls->p;
-  uint32_t v = *p++;
-  if (LJ_UNLIKELY(v >= 0x80)) {
-    int sh = 0;
-    v &= 0x7f;
-    do {
-     v |= ((*p & 0x7f) << (sh += 7));
-     bcread_dec(ls);
-   } while (*p++ >= 0x80);
-  }
-  bcread_dec(ls);
-  ls->p = (char *)p;
+  uint32_t v = lj_buf_ruleb128(&ls->p);
+  lua_assert(ls->p <= ls->pe);
   return v;
 }
 
@@ -160,11 +141,10 @@ static uint32_t bcread_uleb128_33(LexState *ls)
     v &= 0x3f;
     do {
      v |= ((*p & 0x7f) << (sh += 7));
-     bcread_dec(ls);
    } while (*p++ >= 0x80);
   }
-  bcread_dec(ls);
   ls->p = (char *)p;
+  lua_assert(ls->p <= ls->pe);
   return v;
 }
 
@@ -326,25 +306,13 @@ static void bcread_uv(LexState *ls, GCproto *pt, MSize sizeuv)
 }
 
 /* Read a prototype. */
-static GCproto *bcread_proto(LexState *ls)
+GCproto *lj_bcread_proto(LexState *ls)
 {
   GCproto *pt;
   MSize framesize, numparams, flags, sizeuv, sizekgc, sizekn, sizebc, sizept;
   MSize ofsk, ofsuv, ofsdbg;
   MSize sizedbg = 0;
   BCLine firstline = 0, numline = 0;
-  MSize len, startn;
-
-  /* Read length. */
-  if (ls->n > 0 && ls->p[0] == 0) {  /* Shortcut EOF. */
-    ls->n--; ls->p++;
-    return NULL;
-  }
-  bcread_want(ls, 5);
-  len = bcread_uleb128(ls);
-  if (!len) return NULL;  /* EOF */
-  bcread_need(ls, len);
-  startn = ls->n;
 
   /* Read prototype header. */
   flags = bcread_byte(ls);
@@ -413,9 +381,6 @@ static GCproto *bcread_proto(LexState *ls)
     setmref(pt->uvinfo, NULL);
     setmref(pt->varinfo, NULL);
   }
-
-  if (len != startn - ls->n)
-    bcread_error(ls, LJ_ERR_BCBAD);
   return pt;
 }
 
@@ -455,19 +420,33 @@ static int bcread_header(LexState *ls)
 GCproto *lj_bcread(LexState *ls)
 {
   lua_State *L = ls->L;
-  lua_assert(ls->current == BCDUMP_HEAD1);
+  lua_assert(ls->c == BCDUMP_HEAD1);
   bcread_savetop(L, ls, L->top);
-  lj_str_resetbuf(&ls->sb);
+  lj_buf_reset(&ls->sb);
   /* Check for a valid bytecode dump header. */
   if (!bcread_header(ls))
     bcread_error(ls, LJ_ERR_BCFMT);
   for (;;) {  /* Process all prototypes in the bytecode dump. */
-    GCproto *pt = bcread_proto(ls);
-    if (!pt) break;
+    GCproto *pt;
+    MSize len;
+    const char *startp;
+    /* Read length. */
+    if (ls->p < ls->pe && ls->p[0] == 0) {  /* Shortcut EOF. */
+      ls->p++;
+      break;
+    }
+    bcread_want(ls, 5);
+    len = bcread_uleb128(ls);
+    if (!len) break;  /* EOF */
+    bcread_need(ls, len);
+    startp = ls->p;
+    pt = lj_bcread_proto(ls);
+    if (ls->p != startp + len)
+      bcread_error(ls, LJ_ERR_BCBAD);
     setprotoV(L, L->top, pt);
     incr_top(L);
   }
-  if ((int32_t)ls->n > 0 || L->top-1 != bcread_oldtop(L, ls))
+  if (ls->p < ls->pe || L->top-1 != bcread_oldtop(L, ls))
     bcread_error(ls, LJ_ERR_BCBAD);
   /* Pop off last prototype. */
   L->top--;