From f9ff6498d85399cc615e703c78ffb3153f1be3fd Mon Sep 17 00:00:00 2001
From: vsc <vsc@b08c6af1-5177-4d33-ba66-4b1c6b8b522a>
Date: Wed, 30 Jan 2002 03:49:50 +0000
Subject: [PATCH] more simplifications on the catch and throw mechanism after
 having failed the ISO testset.

git-svn-id: https://yap.svn.sf.net/svnroot/yap/trunk@341 b08c6af1-5177-4d33-ba66-4b1c6b8b522a
---
 C/exec.c | 34 +++++++++++++++++++---------------
 C/init.c |  2 +-
 C/save.c |  4 ++--
 H/Heap.h |  6 +++---
 4 files changed, 25 insertions(+), 21 deletions(-)

diff --git a/C/exec.c b/C/exec.c
index 30e212fa4..15e6af8f8 100644
--- a/C/exec.c
+++ b/C/exec.c
@@ -1252,24 +1252,28 @@ p_clean_ifcp(void) {
 
 Int
 JumpToEnv(Term t) {
-  yamop *min = (yamop *)(PredCatch->CodeOfPred);
-  yamop *max = (yamop *)(PredThrow->CodeOfPred);
-  CELL *cur = ENV, *env;
-  yamop *cpe = (yamop *)(cur[E_CP]);
+  yamop *pos = (yamop *)(PredDollarCatch->LastClause);
+  CELL *env;
 
-  while (cpe < min || cpe > max) {
-    cur = (CELL *)cur[E_E];
-    cpe = (yamop *)(cur[E_CP]);
-  }
-  CP = cpe;
-  env = (CELL *)cur[E_E];
-  YENV = ENV = (CELL *)(env[E_E]);
-  while (B->cp_b < (choiceptr)env) {
+  do {
+    /* find the first choicepoint that may be a catch */
+    while (B->cp_ap != pos) {
+      B = B->cp_b;
+    }
+    /* is it a continuation? */
+    env = B->cp_env;
+    while (env > ENV)
+      ENV = (CELL *)ENV[E_E];
+    /* yes, we found it ! */
+    if (env == ENV) break;
+    /* oops, try next */
     B = B->cp_b;
-  }
-  B->cp_cp = (yamop *)(env[E_CP]);
+  } while (TRUE);
+  /* step one environment above */
+  B->cp_cp = (yamop *)env[E_CP];
   B->cp_ap = (yamop *)(PredHandleThrow->LastClause);
-  B->cp_env = ENV;
+  B->cp_env = (CELL *)env[E_E];
+  /* cannot recover Heap because of copy term :-( */
   B->cp_h = H;
   /* I could backtrack here, but it is easier to leave the unwinding
      to the emulator */
diff --git a/C/init.c b/C/init.c
index f28335598..a6c8269d9 100644
--- a/C/init.c
+++ b/C/init.c
@@ -1012,7 +1012,7 @@ InitCodes(void)
   CurrentModule = 0;
   heap_regs->dead_clauses = NULL;
   heap_regs->pred_meta_call = RepPredProp(PredPropByFunc(MkFunctor(heap_regs->atom_meta_call,4),0));
-  heap_regs->pred_catch = RepPredProp(PredPropByFunc(MkFunctor(LookupAtom("catch"),3),0));
+  heap_regs->pred_dollar_catch = RepPredProp(PredPropByFunc(MkFunctor(LookupAtom("$catch"),3),0));
   heap_regs->pred_throw = RepPredProp(PredPropByFunc(FunctorThrow,0));
   heap_regs->pred_handle_throw = RepPredProp(PredPropByFunc(MkFunctor(LookupAtom("$handle_throw"),3),0));
   ReleaseAtom(AtomOfTerm(heap_regs->term_refound_var));
diff --git a/C/save.c b/C/save.c
index 6e3fa7e1f..780cd7361 100644
--- a/C/save.c
+++ b/C/save.c
@@ -1122,8 +1122,8 @@ restore_codes(void)
     (PredEntry *)AddrAdjust((ADDR)heap_regs->pred_goal_expansion);
   heap_regs->pred_meta_call =
     (PredEntry *)AddrAdjust((ADDR)heap_regs->pred_meta_call);
-  heap_regs->pred_catch =
-    (PredEntry *)AddrAdjust((ADDR)heap_regs->pred_catch);
+  heap_regs->pred_dollar_catch =
+    (PredEntry *)AddrAdjust((ADDR)heap_regs->pred_dollar_catch);
   heap_regs->pred_throw =
     (PredEntry *)AddrAdjust((ADDR)heap_regs->pred_throw);
   heap_regs->pred_handle_throw =
diff --git a/H/Heap.h b/H/Heap.h
index 3da737635..90bbce9e2 100644
--- a/H/Heap.h
+++ b/H/Heap.h
@@ -10,7 +10,7 @@
 * File:		Heap.h         						 *
 * mods:									 *
 * comments:	Heap Init Structure					 *
-* version:      $Id: Heap.h,v 1.22 2002-01-28 04:30:40 vsc Exp $	 *
+* version:      $Id: Heap.h,v 1.23 2002-01-30 03:49:50 vsc Exp $	 *
 *************************************************************************/
 
 /* information that can be stored in Code Space */
@@ -270,7 +270,7 @@ typedef struct various_codes {
   void *last_wtime;
   PredEntry *pred_goal_expansion;
   PredEntry *pred_meta_call;
-  PredEntry *pred_catch;
+  PredEntry *pred_dollar_catch;
   PredEntry *pred_throw;
   PredEntry *pred_handle_throw;
   UInt n_of_file_aliases;
@@ -461,7 +461,7 @@ typedef struct various_codes {
 #define  TermReFoundVar           heap_regs->term_refound_var
 #define  PredGoalExpansion        heap_regs->pred_goal_expansion
 #define  PredMetaCall             heap_regs->pred_meta_call
-#define  PredCatch                heap_regs->pred_catch
+#define  PredDollarCatch          heap_regs->pred_dollar_catch
 #define  PredThrow                heap_regs->pred_throw
 #define  PredHandleThrow          heap_regs->pred_handle_throw
 #define  NOfFileAliases           heap_regs->n_of_file_aliases