duskos

commit 9903957f8a8e246ff0f2d14dfa6531abe98de1e0
parent f1317253f641fb146334bc42fe4a807a5a029a2b
Author: Virgil Dupras <hsoft@hardcoded.net>
Date:   Wed, 16 Nov 2022 11:08:19 -0500

app/uxn: add byte/short mode support

Diffstat:
M
fs/app/uxn/vm.c
 | 
67
+++++++++++++++++++++++++++++++------------------------------------
M
fs/tests/app/uxn/dummy.bin
 | 
0

M
fs/tests/app/uxn/dummy.tal
 | 
4
+++-
M
fs/tests/app/uxn/vm.fs
 | 
3
++-

4 files changed, 36 insertions(+), 38 deletions(-)
diff --git a/fs/app/uxn/vm.c b/fs/app/uxn/vm.c
@@ -28,64 +28,57 @@ static Stack rst;
 static Stack *s;
 static Device dev[$10];
 static unsigned short pc; // Program Counter
+static int bs; // byte/short 0=byte 1=short
 
 static void error(int code) {
     printf(code, "Error %d encountered\n");
     abort();
 }
 
-void push8(unsigned char val) {
-    if (s->ptr == $ff) { error(2); } else { s->dat[s->ptr++] = val; }
-}
-
 void push(unsigned short val) {
-    if (s->ptr >= $fe) { error(2); } else {
+    if (s->ptr >= $ff-bs) error(2);
+    if (bs) {
         s->dat[s->ptr] = val >> 8;
         s->dat[s->ptr+1] = val;
         s->ptr += 2 ;
+    } else {
+        s->dat[s->ptr++] = val;
     }
 }
 
-unsigned char pop8() {
-    if (!s->ptr) { error(0); } else { return s->dat[--s->ptr]; }
-}
-
-unsigned short pop16() {
-    unsigned short val;
-    if (s->ptr <= 1) { error(0); } else {
+unsigned short pop() {
+    if (s->ptr <= bs) error(0);
+    if (bs) {
         s->ptr -= 2;
-        val = s->dat[s->ptr] << 8;
-        val |= s->dat[s->ptr+1];
-        return val;
+        return (s->dat[s->ptr] << 8) | s->dat[s->ptr+1];
+    } else {
+        return s->dat[--s->ptr];
     }
 }
 
-void poke8(unsigned short addr, unsigned char val) {
-    ram[addr] = val;
-}
-
-void poke16(unsigned short addr, unsigned short val) {
-    ram[addr] = val >> 8;
-    ram[addr+1] = val;
-}
-
-unsigned char peek8(unsigned short addr) {
-    return ram[addr];
+void poke(unsigned short addr, unsigned short val) {
+    if (bs) {
+        ram[addr] = val >> 8;
+        ram[addr+1] = val;
+    } else {
+        ram[addr] = val;
+    }
 }
 
-unsigned short peek16(unsigned short addr) {
-    unsigned short val;
-    val = ram[addr] << 8;
-    val |= ram[addr+1];
-    return val;
+unsigned short peek(unsigned short addr) {
+    if (bs) {
+        return (ram[addr] << 8) | ram[addr+1];
+    } else {
+        return ram[addr];
+    }
 }
 
 /* Operations */
 static void _err() { error(42); }
-static void LIT() { push8(peek8(pc++)); }
-static void INC() { push8(pop8()+1); }
-static void DUP() { unsigned char x = pop8(); push8(x); push8(x); }
-static void ADD() { push8(pop8() + pop8()); }
+static void LIT() { push(peek(pc++)); }
+static void INC() { push(pop()+1); }
+static void DUP() { unsigned short x = pop(); push(x); push(x); }
+static void ADD() { push(pop() + pop()); }
 static VMOP ops[$20] = {
     LIT, INC, _err, _err, _err, _err, DUP, _err,
     _err, _err, _err, _err, _err, _err, _err, _err,
@@ -94,10 +87,12 @@ static VMOP ops[$20] = {
 
 void uxn_exec() {
     unsigned char op;
-    while (op = peek8(pc++)) {
+    while (op = ram[pc++]) {
+        bs = (op >> 5) & 1;
         op &= $1f;
         ops[op]();
     }
+    bs = 0; // for debugging pop()s
 }
 
 void uxn_init() {
diff --git a/fs/tests/app/uxn/dummy.bin b/fs/tests/app/uxn/dummy.bin
Binary files differ.
diff --git a/fs/tests/app/uxn/dummy.tal b/fs/tests/app/uxn/dummy.tal
@@ -1,2 +1,4 @@
 |0100 
-#2a DUP INC ADD BRK
+#2a DUP INC ( 2a 2b )
+DUP2 ADD2 ( 54 56 )
+BRK
diff --git a/fs/tests/app/uxn/vm.fs b/fs/tests/app/uxn/vm.fs
@@ -7,5 +7,6 @@ ram $100 + S" /tests/app/uxn/dummy.bin" curpath :find# Path :open
 tuck File :readall File :close
 uxn_init
 uxn_exec
-pop8 85 #eq
+pop $56 #eq
+pop $54 #eq
 testend