From 978c51bb2629483dc7fce2a91aa32ea80e5f7a15 Mon Sep 17 00:00:00 2001
From: Yuichi Nishiwaki <yuichi.nishiwaki@gmail.com>
Date: Thu, 18 Sep 2014 14:50:01 +0900
Subject: [PATCH] compact struct pic_jmpbuf

---
 cont.c                 | 28 ++++++++++++++--------------
 error.c                | 40 ++++++++++++++++++++++------------------
 gc.c                   | 33 ++++++++++++++++-----------------
 include/picrin.h       |  9 +++++----
 include/picrin/cont.h  |  6 +++---
 include/picrin/error.h |  9 ---------
 state.c                | 12 +++++++-----
 7 files changed, 67 insertions(+), 70 deletions(-)

diff --git a/cont.c b/cont.c
index 8fba3c78..563332aa 100644
--- a/cont.c
+++ b/cont.c
@@ -131,14 +131,19 @@ save_cont(pic_state *pic, struct pic_cont **c)
 
   cont->sp_offset = pic->sp - pic->stbase;
   cont->st_len = pic->stend - pic->stbase;
-  cont->st_ptr = (pic_value *)pic_alloc(pic, sizeof(pic_value) * cont->st_len);
+  cont->st_ptr = pic_alloc(pic, sizeof(pic_value) * cont->st_len);
   memcpy(cont->st_ptr, pic->stbase, sizeof(pic_value) * cont->st_len);
 
   cont->ci_offset = pic->ci - pic->cibase;
   cont->ci_len = pic->ciend - pic->cibase;
-  cont->ci_ptr = (pic_callinfo *)pic_alloc(pic, sizeof(pic_callinfo) * cont->ci_len);
+  cont->ci_ptr = pic_alloc(pic, sizeof(pic_callinfo) * cont->ci_len);
   memcpy(cont->ci_ptr, pic->cibase, sizeof(pic_callinfo) * cont->ci_len);
 
+  cont->xp_offset = pic->xp - pic->xpbase;
+  cont->xp_len = pic->xpend - pic->xpbase;
+  cont->xp_ptr = pic_alloc(pic, sizeof(struct pic_proc *) * cont->xp_len);
+  memcpy(cont->xp_ptr, pic->xpbase, sizeof(struct pic_proc *) * cont->xp_len);
+
   cont->ip = pic->ip;
 
   cont->arena_idx = pic->arena_idx;
@@ -146,11 +151,6 @@ save_cont(pic_state *pic, struct pic_cont **c)
   cont->arena = (struct pic_object **)pic_alloc(pic, sizeof(struct pic_object *) * pic->arena_size);
   memcpy(cont->arena, pic->arena, sizeof(struct pic_object *) * pic->arena_size);
 
-  cont->try_jmp_idx = pic->try_jmp_idx;
-  cont->try_jmp_size = pic->try_jmp_size;
-  cont->try_jmps = pic_alloc(pic, sizeof(struct pic_jmpbuf) * pic->try_jmp_size);
-  memcpy(cont->try_jmps, pic->try_jmps, sizeof(struct pic_jmpbuf) * pic->try_jmp_size);
-
   cont->results = pic_undef_value();
 }
 
@@ -178,16 +178,21 @@ restore_cont(pic_state *pic, struct pic_cont *cont)
 
   pic->wind = cont->wind;
 
-  pic->stbase = (pic_value *)pic_realloc(pic, pic->stbase, sizeof(pic_value) * cont->st_len);
+  pic->stbase = pic_realloc(pic, pic->stbase, sizeof(pic_value) * cont->st_len);
   memcpy(pic->stbase, cont->st_ptr, sizeof(pic_value) * cont->st_len);
   pic->sp = pic->stbase + cont->sp_offset;
   pic->stend = pic->stbase + cont->st_len;
 
-  pic->cibase = (pic_callinfo *)pic_realloc(pic, pic->cibase, sizeof(pic_callinfo) * cont->ci_len);
+  pic->cibase = pic_realloc(pic, pic->cibase, sizeof(pic_callinfo) * cont->ci_len);
   memcpy(pic->cibase, cont->ci_ptr, sizeof(pic_callinfo) * cont->ci_len);
   pic->ci = pic->cibase + cont->ci_offset;
   pic->ciend = pic->cibase + cont->ci_len;
 
+  pic->xpbase = pic_realloc(pic, pic->xpbase, sizeof(struct pic_proc *) * cont->xp_len);
+  memcpy(pic->xpbase, cont->xp_ptr, sizeof(struct pic_proc *) * cont->xp_len);
+  pic->xp = pic->xpbase + cont->xp_offset;
+  pic->xpend = pic->xpbase + cont->xp_len;
+
   pic->ip = cont->ip;
 
   pic->arena = (struct pic_object **)pic_realloc(pic, pic->arena, sizeof(struct pic_object *) * cont->arena_size);
@@ -195,11 +200,6 @@ restore_cont(pic_state *pic, struct pic_cont *cont)
   pic->arena_size = cont->arena_size;
   pic->arena_idx = cont->arena_idx;
 
-  pic->try_jmps = pic_realloc(pic, pic->try_jmps, sizeof(struct pic_jmpbuf) * cont->try_jmp_size);
-  memcpy(pic->try_jmps, cont->try_jmps, sizeof(struct pic_jmpbuf) * cont->try_jmp_size);
-  pic->try_jmp_size = cont->try_jmp_size;
-  pic->try_jmp_idx = cont->try_jmp_idx;
-
   memcpy(cont->stk_pos, cont->stk_ptr, cont->stk_len);
 
   longjmp(tmp->jmp, 1);
diff --git a/error.c b/error.c
index 4eb34157..8023c0be 100644
--- a/error.c
+++ b/error.c
@@ -89,7 +89,7 @@ static pic_value
 native_push_try(pic_state *pic)
 {
   struct pic_proc *cont, *handler;
-  struct pic_jmpbuf *try_jmp;
+  size_t xp_len, xp_offset;
 
   pic_get_args(pic, "l", &cont);
 
@@ -97,13 +97,15 @@ native_push_try(pic_state *pic)
 
   pic_attr_set(pic, handler, "@@escape", pic_obj_value(cont));
 
-  if (pic->try_jmp_idx >= pic->try_jmp_size) {
-    pic->try_jmp_size *= 2;
-    pic->try_jmps = pic_realloc(pic, pic->try_jmps, sizeof(struct pic_jmpbuf) * pic->try_jmp_size);
+  if (pic->xp >= pic->xpend) {
+    xp_len = (pic->xpend - pic->xpbase) * 2;
+    xp_offset = pic->xp - pic->xpbase;
+    pic->xpbase = pic_realloc(pic, pic->xpbase, sizeof(struct pic_proc *) * xp_len);
+    pic->xp = pic->xpbase + xp_offset;
+    pic->xpend = pic->xpbase + xp_len;
   }
 
-  try_jmp = pic->try_jmps + pic->try_jmp_idx++;
-  try_jmp->handler = handler;
+  *pic->xp++ = handler;
 
   return pic_true_value();
 }
@@ -121,7 +123,7 @@ pic_push_try(pic_state *pic)
 void
 pic_pop_try(pic_state *pic)
 {
-  --pic->try_jmp_idx;
+  --pic->xp;
 }
 
 struct pic_error *
@@ -147,19 +149,17 @@ pic_raise_continuable(pic_state *pic, pic_value err)
   struct pic_proc *handler;
   pic_value v;
 
-  if (pic->try_jmp_idx == 0) {
+  if (pic->xp == pic->xpbase) {
     pic_panic(pic, "no exception handler registered");
   }
 
-  handler = pic->try_jmps[pic->try_jmp_idx - 1].handler;
+  handler = *--pic->xp;
 
   pic_gc_protect(pic, pic_obj_value(handler));
 
-  pic->try_jmp_idx--;
+  v = pic_apply1(pic, handler, err);
 
-  v = pic_apply1(pic, pic->try_jmps[pic->try_jmp_idx].handler, err);
-
-  pic->try_jmps[pic->try_jmp_idx++].handler = handler;
+  *pic->xp++ = handler;
 
   return v;
 }
@@ -197,19 +197,23 @@ pic_error_with_exception_handler(pic_state *pic)
 {
   struct pic_proc *handler, *thunk;
   pic_value val;
+  size_t xp_len, xp_offset;
 
   pic_get_args(pic, "ll", &handler, &thunk);
 
-  if (pic->try_jmp_idx >= pic->try_jmp_size) {
-    pic->try_jmp_size *= 2;
-    pic->try_jmps = pic_realloc(pic, pic->try_jmps, sizeof(struct pic_jmpbuf) * pic->try_jmp_size);
+  if (pic->xp >= pic->xpend) {
+    xp_len = (pic->xpend - pic->xpbase) * 2;
+    xp_offset = pic->xp - pic->xpbase;
+    pic->xpbase = pic_realloc(pic, pic->xpbase, sizeof(struct pic_proc *) * xp_len);
+    pic->xp = pic->xpbase + xp_offset;
+    pic->xpend = pic->xpbase + xp_len;
   }
 
-  pic->try_jmps[pic->try_jmp_idx++].handler = handler;
+  *pic->xp++ = handler;
 
   val = pic_apply0(pic, thunk);
 
-  pic->try_jmp_idx--;
+  --pic->xp;
 
   return val;
 }
diff --git a/gc.c b/gc.c
index 15304788..7ac019ff 100644
--- a/gc.c
+++ b/gc.c
@@ -416,6 +416,7 @@ gc_mark_object(pic_state *pic, struct pic_object *obj)
     struct pic_cont *cont = (struct pic_cont *)obj;
     pic_value *stack;
     pic_callinfo *ci;
+    struct pic_proc **xhandler;
     size_t i;
 
     /* winder */
@@ -433,18 +434,16 @@ gc_mark_object(pic_state *pic, struct pic_object *obj)
       }
     }
 
+    /* exception handlers */
+    for (xhandler = cont->xp_ptr; xhandler != cont->xp_ptr + cont->xp_offset; ++xhandler) {
+      gc_mark_object(pic, (struct pic_object *)*xhandler);
+    }
+
     /* arena */
     for (i = 0; i < (size_t)cont->arena_idx; ++i) {
       gc_mark_object(pic, cont->arena[i]);
     }
 
-    /* error handlers */
-    for (i = 0; i < cont->try_jmp_idx; ++i) {
-      if (cont->try_jmps[i].handler) {
-        gc_mark_object(pic, (struct pic_object *)cont->try_jmps[i].handler);
-      }
-    }
-
     /* result values */
     gc_mark(pic, cont->results);
     break;
@@ -562,7 +561,8 @@ gc_mark_phase(pic_state *pic)
 {
   pic_value *stack;
   pic_callinfo *ci;
-  size_t i, j;
+  struct pic_proc **xhandler;
+  size_t j;
   xh_entry *it;
 
   /* winder */
@@ -582,8 +582,10 @@ gc_mark_phase(pic_state *pic)
     }
   }
 
-  /* error object */
-  gc_mark(pic, pic->err);
+  /* exception handlers */
+  for (xhandler = pic->xpbase; xhandler != pic->xp; ++xhandler) {
+    gc_mark_object(pic, (struct pic_object *)*xhandler);
+  }
 
   /* arena */
   for (j = 0; j < pic->arena_idx; ++j) {
@@ -600,13 +602,10 @@ gc_mark_phase(pic_state *pic)
     gc_mark_object(pic, xh_val(it, struct pic_object *));
   }
 
-  /* error handlers */
-  for (i = 0; i < pic->try_jmp_idx; ++i) {
-    if (pic->try_jmps[i].handler) {
-      gc_mark_object(pic, (struct pic_object *)pic->try_jmps[i].handler);
-    }
-  }
+  /* error object */
+  gc_mark(pic, pic->err);
 
+  /* features */
   gc_mark(pic, pic->features);
 
   /* readers */
@@ -669,8 +668,8 @@ gc_finalize_object(pic_state *pic, struct pic_object *obj)
     pic_free(pic, cont->stk_ptr);
     pic_free(pic, cont->st_ptr);
     pic_free(pic, cont->ci_ptr);
+    pic_free(pic, cont->xp_ptr);
     pic_free(pic, cont->arena);
-    pic_free(pic, cont->try_jmps);
     break;
   }
   case PIC_TT_SENV: {
diff --git a/include/picrin.h b/include/picrin.h
index 17a159dd..b00e451d 100644
--- a/include/picrin.h
+++ b/include/picrin.h
@@ -75,6 +75,9 @@ typedef struct {
   pic_callinfo *ci;
   pic_callinfo *cibase, *ciend;
 
+  struct pic_proc **xp;
+  struct pic_proc **xpbase, **xpend;
+
   pic_code *ip;
 
   struct pic_lib *lib;
@@ -111,16 +114,14 @@ typedef struct {
 
   struct pic_reader *reader;
 
-  pic_value err;
-  struct pic_jmpbuf *try_jmps;
-  size_t try_jmp_size, try_jmp_idx;
-
   struct pic_heap *heap;
   struct pic_object **arena;
   size_t arena_size, arena_idx;
 
   struct pic_port *xSTDIN, *xSTDOUT, *xSTDERR;
 
+  pic_value err;
+
   char *native_stack_start;
 } pic_state;
 
diff --git a/include/picrin/cont.h b/include/picrin/cont.h
index 740a1175..503651f1 100644
--- a/include/picrin/cont.h
+++ b/include/picrin/cont.h
@@ -24,15 +24,15 @@ struct pic_cont {
   pic_callinfo *ci_ptr;
   size_t ci_offset, ci_len;
 
+  struct pic_proc **xp_ptr;
+  size_t xp_offset, xp_len;
+
   pic_code *ip;
 
   struct pic_object **arena;
   size_t arena_size;
   int arena_idx;
 
-  struct pic_jmpbuf *try_jmps;
-  size_t try_jmp_idx, try_jmp_size;
-
   pic_value results;
 };
 
diff --git a/include/picrin/error.h b/include/picrin/error.h
index 8686d3ff..0549c69d 100644
--- a/include/picrin/error.h
+++ b/include/picrin/error.h
@@ -9,15 +9,6 @@
 extern "C" {
 #endif
 
-struct pic_jmpbuf {
-  jmp_buf here;
-  struct pic_proc *handler;
-  ptrdiff_t ci_offset;
-  ptrdiff_t sp_offset;
-  pic_code *ip;
-  jmp_buf *prev_jmp;
-};
-
 /* do not return from try block! */
 
 #define pic_try                                 \
diff --git a/state.c b/state.c
index e75876a2..e61aef44 100644
--- a/state.c
+++ b/state.c
@@ -42,6 +42,10 @@ pic_open(int argc, char *argv[], char **envp)
   pic->cibase = pic->ci = calloc(PIC_STACK_SIZE, sizeof(pic_callinfo));
   pic->ciend = pic->cibase + PIC_STACK_SIZE;
 
+  /* exception handler */
+  pic->xpbase = pic->xp = calloc(PIC_RESCUE_SIZE, sizeof(struct pic_proc *));
+  pic->xpend = pic->xpbase + PIC_RESCUE_SIZE;
+
   /* memory heap */
   pic->heap = pic_heap_open();
 
@@ -70,11 +74,8 @@ pic_open(int argc, char *argv[], char **envp)
   pic->reader->trie = pic_make_trie(pic);
   xh_init_int(&pic->reader->labels, sizeof(pic_value));
 
-  /* error handling */
+  /* raised error object */
   pic->err = pic_undef_value();
-  pic->try_jmps = calloc(PIC_RESCUE_SIZE, sizeof(struct pic_jmpbuf));
-  pic->try_jmp_idx = 0;
-  pic->try_jmp_size = PIC_RESCUE_SIZE;
 
   /* standard ports */
   pic->xSTDIN = NULL;
@@ -191,6 +192,7 @@ pic_close(pic_state *pic)
   /* clear out root objects */
   pic->sp = pic->stbase;
   pic->ci = pic->cibase;
+  pic->xp = pic->xpbase;
   pic->arena_idx = 0;
   pic->err = pic_undef_value();
   xh_clear(&pic->macros);
@@ -206,6 +208,7 @@ pic_close(pic_state *pic)
   /* free runtime context */
   free(pic->stbase);
   free(pic->cibase);
+  free(pic->xpbase);
 
   /* free reader struct */
   xh_destroy(&pic->reader->labels);
@@ -213,7 +216,6 @@ pic_close(pic_state *pic)
   free(pic->reader);
 
   /* free global stacks */
-  free(pic->try_jmps);
   xh_destroy(&pic->syms);
   xh_destroy(&pic->globals);
   xh_destroy(&pic->macros);