From 75d91850279db3e93834b1d38bdf074dd235b3de Mon Sep 17 00:00:00 2001
From: Brad Nelson <flagxor@gmail.com>
Date: Sat, 14 Jan 2023 22:53:30 -0800
Subject: [PATCH] Align PARK/UNPARK with THROW/CATCH.

---
 common/core.h          |  2 +-
 common/tier0_opcodes.h | 10 +++++-----
 esp32/builtins.cpp     |  2 +-
 web/web.template.js    | 22 ++++++++++++++++------
 4 files changed, 23 insertions(+), 13 deletions(-)

diff --git a/common/core.h b/common/core.h
index 6b3a24e..a4544ee 100644
--- a/common/core.h
+++ b/common/core.h
@@ -285,9 +285,9 @@ static void forth_init(int argc, char *argv[],
   g_sys->tib = src;
   g_sys->ntib = src_len;
 
+  *++rp = (cell_t) start;
   *++rp = (cell_t) fp;
   *++rp = (cell_t) sp;
-  *++rp = (cell_t) start;
   g_sys->rp = rp;
   g_sys->runner = forth_run;
 }
diff --git a/common/tier0_opcodes.h b/common/tier0_opcodes.h
index 0dbb2f8..8b5e1d3 100644
--- a/common/tier0_opcodes.h
+++ b/common/tier0_opcodes.h
@@ -32,11 +32,11 @@ typedef uintptr_t ucell_t;
 #define DUP (*++sp = tos)
 #define PUSH DUP; tos = (cell_t)
 
-#define PARK   DUP; *++rp = (cell_t) fp; *++rp = (cell_t) sp; *++rp = (cell_t) ip
-#define UNPARK ip = (cell_t *) *rp--; sp = (cell_t *) *rp--; fp = (float *) *rp--; DROP
-#define THROWIT(n) rp = *g_sys->throw_handler; *g_sys->throw_handler = (cell_t *) *rp--; \
-                   sp = (cell_t *) *rp--; fp = (float *) *rp--; ip = (cell_t *) *rp--; \
-                   NIP; tos = (n);
+#define PARK   *++rp = (cell_t) ip; *++rp = (cell_t) fp; DUP; *++rp = (cell_t) sp;
+#define UNPARK sp = (cell_t *) *rp--; DROP; fp = (float *) *rp--; ip = (cell_t *) *rp--;
+
+#define THROWIT(n) \
+  rp = *g_sys->throw_handler; *g_sys->throw_handler = (cell_t *) *rp--; UNPARK; tos = (n);
 
 #define TOFLAGS(xt) ((uint8_t *) (((cell_t *) (xt)) - 1))
 #define TONAMELEN(xt) (TOFLAGS(xt) + 1)
diff --git a/esp32/builtins.cpp b/esp32/builtins.cpp
index 273b254..683478e 100644
--- a/esp32/builtins.cpp
+++ b/esp32/builtins.cpp
@@ -68,9 +68,9 @@ static void IRAM_ATTR HandleInterrupt(void *arg) {
   cell_t stack[INTERRUPT_STACK_CELLS];
   stack[0] = args->arg;
   cell_t *rp = rstack;
+  *++rp = (cell_t) code;
   *++rp = (cell_t) (fstack + 1);
   *++rp = (cell_t) (stack + 1);
-  *++rp = (cell_t) code;
   forth_run(rp);
 }
 
diff --git a/web/web.template.js b/web/web.template.js
index ed8fe49..11a5f40 100644
--- a/web/web.template.js
+++ b/web/web.template.js
@@ -340,15 +340,22 @@ function FConvert(pos, n, ret) {
 function Evaluate1(rp) {
   var call = 0;
   var tos, sp, ip, fp;
+
   // UNPARK
-  ip = i32[rp>>2]; rp -= 4; sp = i32[rp>>2]; rp -= 4; fp = i32[rp>>2]; rp -= 4; tos = i32[sp>>2]; sp -= 4;
+  sp = i32[rp>>2]; rp -= 4;
+  tos = i32[sp>>2]; sp -= 4;
+  fp = i32[rp>>2]; rp -= 4;
+  ip = i32[rp>>2]; rp -= 4;
 
   var name = sp + 8;
   var len = Parse(32, name);
   if (len == 0) {  // ignore empty
     sp += 4; i32[sp>>2] = tos; tos = 0;
     // PARK
-    sp += 4; i32[sp>>2] = tos; rp += 4; i32[rp>>2] = fp; rp += 4; i32[rp>>2] = sp; rp += 4; i32[rp>>2] = ip;
+    rp += 4; i32[rp>>2] = ip;
+    rp += 4; i32[rp>>2] = fp;
+    sp += 4; i32[sp>>2] = tos;
+    rp += 4; i32[rp>>2] = sp;
     return rp;
   }
   name = i32[name>>2];
@@ -388,7 +395,10 @@ function Evaluate1(rp) {
   }
   sp += 4; i32[sp>>2] = tos; tos = call;
   // PARK
-  sp += 4; i32[sp>>2] = tos; rp += 4; i32[rp>>2] = fp; rp += 4; i32[rp>>2] = sp; rp += 4; i32[rp>>2] = ip;
+  rp += 4; i32[rp>>2] = ip;
+  rp += 4; i32[rp>>2] = fp;
+  sp += 4; i32[sp>>2] = tos;
+  rp += 4; i32[rp>>2] = sp;
 
   return rp;
 }
@@ -452,9 +462,9 @@ function Init() {
   i32[g_sys_ntib>>2] = source_len;
   i32[g_sys_ntib>>2] = source_len;
 
+  rp += 4; i32[rp>>2] = start;
   rp += 4; i32[rp>>2] = fp;
   rp += 4; i32[rp>>2] = sp;
-  rp += 4; i32[rp>>2] = start;
   i32[g_sys_rp>>2] = rp;
 }
 
@@ -546,10 +556,10 @@ function VM(stdlib, foreign, heap) {
 
     // UNPARK
     rp = i32[g_sys_rp>>2]|0;
-    ip = i32[rp>>2]|0; rp = (rp - 4)|0;
     sp = i32[rp>>2]|0; rp = (rp - 4)|0;
-    fp = i32[rp>>2]|0; rp = (rp - 4)|0;
     tos = i32[sp>>2]|0; sp = (sp - 4)|0;
+    fp = i32[rp>>2]|0; rp = (rp - 4)|0;
+    ip = i32[rp>>2]|0; rp = (rp - 4)|0;
     for (;;) {
       //trace(ip|0, sp|0, tos|0);
       w = i32[ip>>2]|0;