commit 6ce6915752655b2b58121bdfaefa39037cc0eb5e
parent fed31a8a16a7d6eb5d46fc49fee385f3854e572a
Author: neauoire <aliceffekt@gmail.com>
Date: Sun, 7 Feb 2021 20:49:00 -0800
Remove conditional oeprations
Diffstat:
5 files changed, 41 insertions(+), 38 deletions(-)
diff --git a/README.md b/README.md
@@ -31,6 +31,7 @@ cc uxn.c -std=c89 -Os -DNDEBUG -g0 -s -Wall -Wno-unknown-pragmas -o uxn
### Operator modes
- `,1234 ,0001 ADD^`, 16-bits operators have the short flag `^`.
+- `,12 ,11 GTH JMP?`, conditional operators have the cond flag `?`.
```
( hello world )
@@ -41,14 +42,19 @@ cc uxn.c -std=c89 -Os -DNDEBUG -g0 -s -Wall -Wno-unknown-pragmas -o uxn
|0100 @RESET
-"hello
+@word1 "hello_word ( len: 0x0b )
@loop
- ,dev1w STR
- ,incr JSU ( call incr )
- ,05 NEQ ,loop ROT JSC
+ ,dev1w STR ( write to stdout )
+ ,incr JSR ( increment itr )
+ ,word1 ,strlen JSR ( get strlen )
+ NEQ ,loop ROT JSR? ( loop != strlen )
-BRK ( RESET )
+BRK
+
+@strlen
+ ,0001 ADD^ LDR
+ RTS
@incr
,iterator LDR
@@ -56,7 +62,7 @@ BRK ( RESET )
,iterator STR
,iterator LDR
RTS
-
+
|c000 @FRAME BRK
|d000 @ERROR BRK
|FFFA .RESET .FRAME .ERROR
@@ -66,10 +72,8 @@ BRK ( RESET )
### Assembler
-- Create a benchmark file
- Implement shorthand operators
- Signed operations
-- zero-page address?
### CPU
@@ -77,6 +81,7 @@ BRK ( RESET )
- Catch overflow/underflow
- A Three-Way Decision Routine(http://www.6502.org/tutorials/compare_instructions.html)
- Draw pixel to screen
+- Redo overflow/underflow mappping
- Detect mouse click
- SDL Layer Emulator
- Build PPU
diff --git a/build.sh b/build.sh
@@ -14,5 +14,5 @@ cc -std=c89 -DDEBUG -Wall -Wno-unknown-pragmas -Wpedantic -Wshadow -Wextra -Werr
cc -std=c89 -DDEBUG -Wall -Wno-unknown-pragmas -Wpedantic -Wshadow -Wextra -Werror=implicit-int -Werror=incompatible-pointer-types -Werror=int-conversion -Wvla -g -Og -fsanitize=address -fsanitize=undefined uxn.c -o uxn
# run
-./uxnasm examples/benchmark.usm boot.rom
+./uxnasm examples/hello.usm boot.rom
./uxn boot.rom
diff --git a/examples/hello.usm b/examples/hello.usm
@@ -10,22 +10,22 @@
@loop
,dev1w STR ( write to stdout )
- ,incr JSU ( increment itr )
- ,word1 ,strlen JSU ( get strlen )
- NEQ ,loop ROT JSC ( loop != strlen )
+ ,incr JSR ( increment itr )
+ ,word1 ,strlen JSR ( get strlen )
+ NEQ ,loop ROT JSR? ( loop != strlen )
BRK
@strlen
,0001 ADD^ LDR
- RTU
+ RTS
@incr
,iterator LDR
,01 ADD
,iterator STR
,iterator LDR
- RTU
+ RTS
|c000 @FRAME BRK
|d000 @ERROR BRK
diff --git a/uxn.c b/uxn.c
@@ -14,7 +14,7 @@ WITH REGARD TO THIS SOFTWARE.
#define FLAG_HALT 0x01
#define FLAG_SHORT 0x02
#define FLAG_SIGN 0x04
-#define FLAG_TRAPS 0x08
+#define FLAG_COND 0x08
typedef unsigned char Uint8;
typedef unsigned short Uint16;
@@ -92,8 +92,6 @@ echom(Memory *m, Uint8 len, char *name)
/* clang-format off */
Uint16 bytes2short(Uint8 a, Uint8 b) { return (a << 8) + b; }
-Uint8 rampeek8(Uint16 s) { return cpu.ram.dat[s] & 0xff; }
-Uint8 mempeek8(Uint16 s) { return cpu.ram.dat[s]; }
Uint16 mempeek16(Uint16 s) { return (cpu.ram.dat[s] << 8) + (cpu.ram.dat[s+1] & 0xff); }
void wspush8(Uint8 b) { cpu.wst.dat[cpu.wst.ptr++] = b; }
void wspush16(Uint16 s) { wspush8(s >> 8); wspush8(s & 0xff); }
@@ -107,16 +105,13 @@ void rspush16(Uint16 a) { cpu.rst.dat[cpu.rst.ptr++] = a; }
/* I/O */
void op_brk() { setflag(FLAG_HALT, 1); }
void op_lit() { cpu.literal += cpu.ram.dat[cpu.ram.ptr++]; }
-void op_nop() { }
+void op_nop() { printf("NOP");}
void op_ldr() { wspush8(cpu.ram.dat[wspop16()]); }
void op_str() { cpu.ram.dat[wspop16()] = wspop8(); }
/* Logic */
-void op_jmu() { cpu.ram.ptr = wspop16(); }
-void op_jmc() { Uint8 a = wspop8(); if(a) op_jmu(); }
-void op_jsu() { rspush16(cpu.ram.ptr); cpu.ram.ptr = wspop16(); }
-void op_jsc() { Uint8 a = wspop8(); if(a) op_jsu(); }
-void op_rtu() { cpu.ram.ptr = rspop16(); }
-void op_rtc() { /* TODO */ }
+void op_jmp() { cpu.ram.ptr = wspop16(); }
+void op_jsr() { rspush16(cpu.ram.ptr); cpu.ram.ptr = wspop16(); }
+void op_rts() { cpu.ram.ptr = rspop16(); }
/* Stack */
void op_pop() { wspop8(); }
void op_dup() { wspush8(wspeek8(1)); }
@@ -156,14 +151,14 @@ void op_lth16() { Uint16 a = wspop16(), b = wspop16(); wspush8(b < a); }
void (*ops[])() = {
op_brk, op_lit, op_nop, op_nop, op_nop, op_nop, op_ldr, op_str,
- op_jmu, op_jmc, op_jsu, op_jsc, op_rtu, op_rtc, op_nop, op_nop,
+ op_jmp, op_jsr, op_nop, op_rts, op_nop, op_nop, op_nop, op_nop,
op_pop, op_dup, op_swp, op_ovr, op_rot, op_and, op_ora, op_rol,
op_add, op_sub, op_mul, op_div, op_equ, op_neq, op_gth, op_lth,
op_pop16, op_dup16, op_swp16, op_ovr16, op_rot16, op_and16, op_ora16, op_rol16,
op_add16, op_sub16, op_mul16, op_div16, op_equ16, op_neq16, op_gth16, op_lth16
};
-Uint8 opr[][2] = {
+Uint8 opr[][2] = { /* TODO */
{0,0}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0},
{0,0}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0},
{0,0}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0},
@@ -202,8 +197,7 @@ opc(Uint8 src, Uint8 *op)
int
eval(void)
{
- Uint8 instr = cpu.ram.dat[cpu.ram.ptr++];
- Uint8 op;
+ Uint8 op, instr = cpu.ram.dat[cpu.ram.ptr++];
/* when literal */
if(cpu.literal > 0) {
wspush8(instr);
@@ -213,19 +207,23 @@ eval(void)
/* when opcode */
opc(instr, &op);
setflag(FLAG_SHORT, (instr >> 5) & 1);
- setflag(FLAG_SIGN, (instr >> 6) & 1);
- if((instr >> 7) & 1)
- printf("Unused flag: %02x\n", instr);
+ setflag(FLAG_SIGN, (instr >> 6) & 1); /* TODO: Implement */
+ setflag(FLAG_COND, (instr >> 7) & 1);
+ /* TODO: overflow */
if(cpu.wst.ptr < opr[op][0])
return error("Stack underflow", op);
+ /* short mode */
if(getflag(FLAG_SHORT))
op += 16;
- (*ops[op])();
-
- /* experimental */
+ /* cond mode */
+ if(getflag(FLAG_COND)) {
+ if(wspop8())
+ (*ops[op])();
+ } else
+ (*ops[op])();
+ /* devices: experimental */
if(cpu.ram.dat[0xfff1])
device1(&cpu.ram.dat[0xfff0], &cpu.ram.dat[0xfff1]);
-
cpu.counter++;
return 1;
}
@@ -245,7 +243,7 @@ debug(void)
getflag(FLAG_HALT) != 0,
getflag(FLAG_SHORT) != 0,
getflag(FLAG_SIGN) != 0,
- getflag(FLAG_TRAPS) != 0);
+ getflag(FLAG_COND) != 0);
}
int
diff --git a/uxnasm.c b/uxnasm.c
@@ -32,7 +32,7 @@ Program p;
char ops[][4] = {
"BRK", "LIT", "---", "---", "PEK", "POK", "LDR", "STR",
- "JMU", "JMC", "JSU", "JSC", "RTU", "RTC", "---", "---",
+ "JMP", "JSR", "RTI", "RTS", "---", "---", "---", "---",
"POP", "DUP", "SWP", "OVR", "ROT", "AND", "ORA", "ROL",
"ADD", "SUB", "MUL", "DIV", "EQU", "NEQ", "GTH", "LTH"
};
@@ -103,7 +103,7 @@ findoperator(char *s)
while(s[3 + m]) {
if(s[3 + m] == '^') i |= (1 << 5); /* mode: 16 bits */
if(s[3 + m] == '~') i |= (1 << 6); /* mode: signed */
- if(s[3 + m] == '&') i |= (1 << 7); /* mode: unused */
+ if(s[3 + m] == '?') i |= (1 << 7); /* mode: conditional */
m++;
}
return i;
