From: Paul Eggert <eggert@cs.ucla.edu>
Date: Tue, 9 Aug 2016 07:37:39 +0000 (-0700)
Subject: Remove arbitrary limit on bytecode maxdepth
X-Git-Tag: emacs-26.0.90~1766
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=cb71a119f7231984e010cc28ef33854721036a0f;p=emacs.git

Remove arbitrary limit on bytecode maxdepth

* src/bytecode.c (exec_byte_code): Remove MAX_ALLOCA-based limit
on bytecode maxdepth, by using SAFE_ALLOCA_LISP instead of alloca.

pipeline is fuller.
---

diff --git a/src/bytecode.c b/src/bytecode.c
index 52f827f282a..0c5b8494d0c 100644
--- a/src/bytecode.c
+++ b/src/bytecode.c
@@ -413,7 +413,7 @@ Lisp_Object
 exec_byte_code (Lisp_Object bytestr, Lisp_Object vector, Lisp_Object maxdepth,
 		Lisp_Object args_template, ptrdiff_t nargs, Lisp_Object *args)
 {
-  ptrdiff_t count = SPECPDL_INDEX ();
+  USE_SAFE_ALLOCA;
 #ifdef BYTE_CODE_METER
   int volatile this_op = 0;
   int prev_op;
@@ -447,15 +447,15 @@ exec_byte_code (Lisp_Object bytestr, Lisp_Object vector, Lisp_Object maxdepth,
 
   stack.byte_string = bytestr;
   stack.pc = stack.byte_string_start = SDATA (bytestr);
-  if (MAX_ALLOCA / word_size <= XFASTINT (maxdepth))
-    memory_full (SIZE_MAX);
   unsigned char quitcounter = 0;
-  int stack_items = XFASTINT (maxdepth) + 1;
-  Lisp_Object *stack_base = alloca (stack_items * sizeof *top);
+  EMACS_INT stack_items = XFASTINT (maxdepth) + 1;
+  Lisp_Object *stack_base;
+  SAFE_ALLOCA_LISP (stack_base, stack_items);
   Lisp_Object *stack_lim = stack_base + stack_items;
   top = stack_base;
   stack.next = byte_stack_list;
   byte_stack_list = &stack;
+  ptrdiff_t count = SPECPDL_INDEX ();
 
   if (!NILP (args_template))
     {
@@ -1699,6 +1699,7 @@ exec_byte_code (Lisp_Object bytestr, Lisp_Object vector, Lisp_Object maxdepth,
       error ("binding stack not balanced (serious byte compiler bug)");
     }
 
+  SAFE_FREE ();
   return result;
 }