From 1eec7ab446e926ef6647e8977f4e9d56af7d8c66 Mon Sep 17 00:00:00 2001
From: crc <>
Date: Sun, 31 Jul 2022 00:46:20 +0000
Subject: [PATCH] Change mem:* API to make memory offset calculation easier
 (from Rick C)

FossilOrigin-Name: 47687a00c3c0e398b7b2baf279ed91c2b236a06b1bf5bbc79fd9bee69d83d456
---
 .gitignore         |  1 +
 tests/malloc.retro |  4 ++++
 vm/nga-c/retro.c   | 12 ++++++------
 3 files changed, 11 insertions(+), 6 deletions(-)
 create mode 100644 .gitignore

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..e660fd9
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+bin/
diff --git a/tests/malloc.retro b/tests/malloc.retro
index 4396077..4e4f62b 100644
--- a/tests/malloc.retro
+++ b/tests/malloc.retro
@@ -36,6 +36,7 @@ n:random
 random-value n:print
 'Storing_value_to_`region1`... print
 region1 random-value mem:set
+region1 #8 + random-value mem:set
 '===OK print nl nl
 ```
 
@@ -45,6 +46,9 @@ region1 random-value mem:set
 '===TEST3:_mem:get print
 'Expect_ s:put 'to_contain_ s:put random-value n:put nl
 'Actual_value:_____ s:put region1 mem:get n:put nl
+'Calculating_memory_offset_should_not_segfault...
+region1 #8 + mem:get
+'Contents_of_(region1_+_1)_=_ s:put n:put nl
 '===OK print nl nl
 ```
 
diff --git a/vm/nga-c/retro.c b/vm/nga-c/retro.c
index b100e85..7000c60 100644
--- a/vm/nga-c/retro.c
+++ b/vm/nga-c/retro.c
@@ -241,29 +241,29 @@ typedef union {
 void malloc_allocate(NgaState *vm) {
   // TODO: Conditionally compile based on host word size?
   double_cell addr = { .val = malloc(stack_pop(vm)) };
-  stack_push(vm, addr.msw);
   stack_push(vm, addr.lsw);
+  stack_push(vm, addr.msw);
 }
 
 void malloc_free(NgaState *vm) {
   double_cell addr;
-  addr.lsw = stack_pop(vm);
   addr.msw = stack_pop(vm);
+  addr.lsw = stack_pop(vm);
   free(addr.val);
 }
 
 void malloc_store(NgaState *vm) {
   CELL value = stack_pop(vm);
   double_cell addr;
-  addr.lsw = stack_pop(vm);
   addr.msw = stack_pop(vm);
+  addr.lsw = stack_pop(vm);
   *(CELL *) addr.val = value;
 }
 
 void malloc_fetch(NgaState *vm) {
   double_cell addr;
-  addr.lsw = stack_pop(vm);
   addr.msw = stack_pop(vm);
+  addr.lsw = stack_pop(vm);
   CELL value = *(CELL *)addr.val;
   stack_push(vm, value);
 }
@@ -271,13 +271,13 @@ void malloc_fetch(NgaState *vm) {
 void malloc_realloc(NgaState *vm) {
   CELL bytes = stack_pop(vm);
   double_cell addr1;
-  addr1.lsw = stack_pop(vm);
   addr1.msw = stack_pop(vm);
+  addr1.lsw = stack_pop(vm);
 
   double_cell addr2;
   addr2.val = realloc(addr1.val, bytes);
-  stack_push(vm, addr2.msw);
   stack_push(vm, addr2.lsw);
+  stack_push(vm, addr2.msw);
 }
 
 void query_malloc(NgaState *vm) {