Started work on simultanious multithreading, and branching.

1 files changed, 46 insertions, 2 deletions

diff --git a/sux.c b/sux.c
index 43699d3..1efbc77 100644
--- a/sux.c
+++ b/sux.c
@@ -3,11 +3,13 @@
 uint64_t a; /* Accumulator. */
 uint64_t y; /* Y index. */
 uint64_t x; /* X index. */
+uint8_t crt; /* Current Running Threads. */
+uint64_t pc[8]; /* Program counter. */
 uint64_t ps; /* Processor status. */
 
-uint64_t alu(uint8_t opcode, uint64_t value) {
+int alu(uint8_t opcode, uint64_t value) {
 	uint64_t sum;
-	uint8_t carry, vf;
+	uint8_t carry = 0, vf = 0;
 	switch(opcode) {
 		/* Add with carry. */
 		case ADC:
@@ -102,4 +104,46 @@ uint64_t alu(uint8_t opcode, uint64_t value) {
 			(a >> value) | (a << (64-value));
 			break;
 	}
+	ps |= vf;
+	ps |= carry;
+	return 1;
+}
+
+int threads(uint8_t opcode, uint64_t value) {
+	uint8_t t = value & 0xFF; /* This tells the CPU, which threads to start, or end. */
+	switch(opcode) {
+		/* Start Thread. */
+		case STT:
+			crt |= t;
+			for (uint8_t i = 0; i < 8; i++)
+				if ((t >> i) & 1)
+					pc[i] = value >> 8;
+			break;
+		/* End Thread. */
+		case ENT:
+			crt &= ~t;
+			for (uint8_t i = 0; i < 8; i++)
+				if ((t >> i) & 1)
+					pc[i] = 0;
+			break;
+	}
+}
+
+int branch(uint8_t opcode, uint64_t value, uint8_t thread) {
+			switch (opcode) {
+				/* Jump. */
+				case JMP:
+					pc[thread] = value;
+					break;
+				/* Jump to subroutine. */
+				case JSR:
+					pc[thread] = value;
+					pushaddr(value);
+					break;
+				/* Return from subroutine. */
+				case RTS:
+					pulladdr();
+					break;
+			}
+	}
 }