* vm.c (vm_make_env_each): add comments about env layout.

  Do not use `i' to specify `new_ep'.
* vm.c (rb_proc_create, rb_vm_make_proc_lambda): envval is not used.



git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@51250 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

2 files changed, 29 insertions, 10 deletions

diff --git a/ChangeLog b/ChangeLog
index b3b7146320..b292f8a31a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+Wed Jul 15 14:39:29 2015  Koichi Sasada  <ko1@atdot.net>
+
+	* vm.c (vm_make_env_each): add comments about env layout.
+	  Do not use `i' to specify `new_ep'.
+
+	* vm.c (rb_proc_create, rb_vm_make_proc_lambda): envval is not used.
+
 Wed Jul 15 08:59:19 2015  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* gc.h (RUBY_MARK_UNLESS_NULL): evaluate the argument only once
diff --git a/vm.c b/vm.c
index 1940c5a53e..918db2de11 100644
--- a/vm.c
+++ b/vm.c
@@ -501,7 +501,7 @@ vm_make_env_each(rb_thread_t *const th, rb_control_frame_t *const cfp)
     VALUE * const ep = cfp->ep;
     rb_env_t *env;
     VALUE *new_ep;
-    int i, local_size, env_size;
+    int local_size, env_size;
 
     if (VM_EP_IN_HEAP_P(th, ep)) {
 	return VM_ENV_EP_ENVVAL(ep);
@@ -533,12 +533,24 @@ vm_make_env_each(rb_thread_t *const th, rb_control_frame_t *const cfp)
     }
 
     if (!RUBY_VM_NORMAL_ISEQ_P(cfp->iseq)) {
-	local_size = 1; /* cref/me */
+	local_size = 1 /* cref/me */;
     }
     else {
 	local_size = cfp->iseq->local_size;
     }
 
+    /*
+     * # local variables on a stack frame (N == local_size)
+     * [lvar1, lvar2, ..., lvarN, SPECVAL]
+     *                            ^
+     *                            ep[0]
+     *
+     * # moved local variables
+     * [lvar1, lvar2, ..., lvarN, SPECVAL, Envval, BlockProcval (if needed)]
+     *  ^                         ^
+     *  env->env[0]               ep[0]
+     */
+
     env_size = local_size +
                1 /* specval */ +
 	       1 /* envval */ +
@@ -548,10 +560,10 @@ vm_make_env_each(rb_thread_t *const th, rb_control_frame_t *const cfp)
     env = xmalloc(sizeof(rb_env_t) + (env_size - 1 /* rb_env_t::env[1] */) * sizeof(VALUE));
     env->env_size = env_size;
 
-    i = local_size + 1 /* specval */;
-    MEMCPY(env->env, ep - local_size, VALUE, i);
+    MEMCPY(env->env, ep - local_size, VALUE, local_size + 1 /* specval */);
+
 #if 0
-    for (i = 0; i <= local_size; i++) {
+    for (i = 0; i < local_size; i++) {
 	if (RUBY_VM_NORMAL_ISEQ_P(cfp->iseq)) {
 	    /* clear value stack for GC */
 	    ep[-local_size + i] = 0;
@@ -568,7 +580,7 @@ vm_make_env_each(rb_thread_t *const th, rb_control_frame_t *const cfp)
     */
     *ep = envval;		/* GC mark */
 
-    new_ep = &env->env[i - 1];
+    new_ep = &env->env[local_size];
     new_ep[1] = envval;
     if (blockprocval) new_ep[2] = blockprocval;
 
@@ -669,7 +681,7 @@ rb_vm_env_local_variables(const rb_env_t *env)
 
 static inline VALUE
 rb_proc_create(VALUE klass, const rb_block_t *block,
-	       VALUE envval, int8_t safe_level, int8_t is_from_method, int8_t is_lambda)
+	       int8_t safe_level, int8_t is_from_method, int8_t is_lambda)
 {
     VALUE procval = rb_proc_alloc(klass);
     rb_proc_t *proc = RTYPEDDATA_DATA(procval);
@@ -692,15 +704,15 @@ rb_vm_make_proc(rb_thread_t *th, const rb_block_t *block, VALUE klass)
 VALUE
 rb_vm_make_proc_lambda(rb_thread_t *th, const rb_block_t *block, VALUE klass, int8_t is_lambda)
 {
-    VALUE procval, envval;
+    VALUE procval;
     rb_control_frame_t *cfp = RUBY_VM_GET_CFP_FROM_BLOCK_PTR(block);
 
     if (block->proc) {
 	rb_bug("rb_vm_make_proc: Proc value is already created.");
     }
 
-    envval = vm_make_env_object(th, cfp);
-    procval = rb_proc_create(klass, block, envval, (int8_t)th->safe_level, 0, is_lambda);
+    vm_make_env_object(th, cfp);
+    procval = rb_proc_create(klass, block, (int8_t)th->safe_level, 0, is_lambda);
 
     if (VMDEBUG) {
 	if (th->stack < block->ep && block->ep < th->stack + th->stack_size) {