`DECODE_LDRSTR:
begin
use_cpsr = `COND_MATTERS(cond);
- use_regs = idxbit(rn) | (insn[20] /* L */ ? 0 : idxbit(rd));
+ use_regs = idxbit(rn) | (insn[25] /* I */ ? idxbit(rm) : 0) | (insn[20] /* L */ ? 0 : idxbit(rd));
def_cpsr = 0;
def_regs = insn[20] /* L */ ? idxbit(rd) : 0;
end
use_cpsr = `COND_MATTERS(cond);
use_regs = 0;
def_cpsr = 0;
- def_regs = 0;
+ def_regs = insn[24] /* L */ ? (16'b1 << 14) : 0;
end
`DECODE_LDCSTC: /* Coprocessor data transfer */
begin
waiting_cpsr = use_cpsr & (cpsr_inflight[0] | cpsr_inflight[1]);
waiting_regs = |(use_regs & (regs_inflight[0] | regs_inflight[1]));
- outstall = (waiting && !inbubble) || stall; /* Happens in an always @*, because it is an exception. */
+ outstall = (waiting && !inbubble && !flush) || stall; /* Happens in an always @*, because it is an exception. */
end
-
+
+ reg delayedflush = 0;
+ always @(posedge clk)
+ if (flush && outstall /* halp! I can't do it now, maybe later? */)
+ delayedflush <= 1;
+ else if (!outstall /* anything has been handled this time around */)
+ delayedflush <= 0;
+
/* Actually do the issue. */
always @(posedge clk)
begin
if (waiting)
$display("ISSUE: Stalling instruction %08x because %d/%d", insn, waiting_cpsr, waiting_regs);
-
+
if (!stall)
begin
cpsr_inflight[0] <= cpsr_inflight[1]; /* I'm not sure how well selects work with arrays, and that seems like a dumb thing to get anusulated by. */
regs_inflight[0] <= regs_inflight[1];
regs_inflight[1] <= (waiting || inbubble || !condition_met) ? 0 : def_regs;
- outbubble <= inbubble | waiting | !condition_met;
+ outbubble <= inbubble | waiting | !condition_met | flush | delayedflush;
outpc <= inpc;
outinsn <= insn;
end