ТЕМА: Си как HDL, или Verilog без always

#define M 8
int a[M];
extern int d;
sort(){
	int cmp[M],pos[M];
	if(d==0){ 
		for(int i=0;i<M-1;i++) a[i]=a[i+1];
		a[M-1]=d;	
	}
	else{
		for(int i=0;i<M;i++) cmp[i]=d>a[i];
		pos[0]=cmp[0];				
		for(int i=1;i<M;i++) pos[i]=cmp[i-1]^cmp[i];		
		for(int i=M-2;i>=0;i--) if(cmp[i]) a[i+1]=a[i];
		for(int i=0;i<M;i++) if(pos[i]) a[i]=d;
	}
}

int d;
main(){
	while(1){
		for(int i=0;i<M;i++) printf(" %d ",a[i]);
		printf("> ");
		scanf("%d",&d);
		sort();
	}
}

module sort #(
	M=8,N=4
)(
	output [M-1:0][N-1:0][8-1:0] a,
	input [N-1:0][8-1:0] d,
	input en,clk
);
	bit [M-1:0] cmp,pos;	
	always@(posedge clk)
	if(en)
		if(d==0) begin 
			for(int i=0;i<M-1;i++) a[i]=a[i+1];
			a[M-1]=d;	
		end
		else begin	
			for(int i=0;i<M;i++) cmp[i]=d>a[i];
			pos[0]=cmp[0];				
			for(int i=1;i<M;i++) pos[i]=cmp[i-1]^cmp[i];	
			for(int i=M-2;i>=0;i--) if(cmp[i]) a[i+1]=a[i];
			for(int i=0;i<M;i++) if(pos[i]) a[i]=d;
		end
endmodule

module sort #(
	M=8,N=4
)(
	output [M-1:0][N-1:0][8-1:0] a,
	input [N-1:0][8-1:0] d,
	input en,clk
);
	bit [M-1:0] cmp,pos;	
	always_comb //или always@*
	begin
		for(int i=0;i<M;i++) cmp[i]=d>a[i];
		pos[0]=cmp[0];				
		for(int i=1;i<M;i++) pos[i]=cmp[i-1]^cmp[i];		
	end 
	
	always_ff@(posedge clk) //или always@(posedge clk)
	if(en)
		if(d==0) begin 
			for(int i=0;i<M-1;i++) a[i]<=a[i+1];
			a[M-1]<=d;	
		end
		else begin		
			for(int i=M-2;i>=0;i--) if(cmp[i]) a[i+1]<=a[i];
			for(int i=0;i<M;i++) if(pos[i]) a[i]<=d;
		end
endmodule

par M=8,N=4;
reg [M][N][8] a;
ext [N][8] d;
ext [1] en;
sort(){
	bit [M] cmp,pos;
	if(en)
		if(d==0){ 
			for(int i=0;i<M-1;i++) a[i]=a[i+1];
			a[M-1]=d;	
		}
		else{
			for(int i=0;i<M;i++) cmp[i]=d>a[i];
			pos[0]=cmp[0];				
			for(int i=1;i<M;i++) pos[i]=cmp[i-1]^cmp[i];		
			for(int i=M-2;i>=0;i--) if(cmp[i]) a[i+1]=a[i];
			for(int i=0;i<M;i++) if(pos[i]) a[i]=d;
		}
}

Family : Cyclone III
Total logic elements : 532
    Total combinational functions : 532
    Dedicated logic registers : 256
Total registers : 256
Total pins : 290

#define N 4
int d[N];
extern char c, en;
calc(){
	static char clr=0;
	if(en)
		if((c>='0')&(c<='9')){
			d[0]=clr?(c&15):(d[0]*10)+(c&15); 
			clr=0;
		}
		else if(c==' '){ 
			for(int i=N-1;i>0;i--) d[i]=d[i-1];
			d[0]=0;
			clr=0;
		}	
		else if((c=='a')|(c=='m')){
			if(c=='a') d[0]=d[0]+d[1];
			else d[0]=d[0]*d[1];
			for(int i=1;i<N-1;i++) d[i]=d[i+1];
			clr=1;
		}
}
#include <conio.h>
char en, c;
main(){
	while(1){
		sleep(10);
		while(kbhit()){ en=1; c=getch(); }
		calc();
		if(en) printf("\r%9d",d[0]);
		en=0;
	}
}

#define N 5
#define R 16
int d[N];
extern int b;
bin2bcd(){
	int k;
	for(int j=0;j<N;j++) d[j]=0; 
	for(int i=R-1;i>=0;i--){ 
		k=(b>>i)&1; 
		for(int j=0;j<N;j++){
			if(d[j]>=5) k=k|6; 
			d[j]=(d[j]<<1)+k;  
			k=(k>>2)&1;
			d[j]=d[j]&15;	
		}	
	}			
}
int b;
main(){
	while(1){
		printf("\n");
		for(int j=N-1;j>=0;j--)printf(" %d",d[j]);
		printf(" > ");
		scanf("%d",&b);
		bin2bcd();
	}
}

bit [16] d0; 
ext [8] c;  
ext [1] c_en;  
calc(){ 
	... 
	d0=d[0];	
}

calc(
	bit [16] d0, 
	ext [8] c,  
	ext [1] c_en 
){
	...

calc(
	int *d0, 
	char c,  
	char c_en 
){
	... 
	*d0=d[0]; 
}

main(){
	...
	calc(&d0,c,en);
	...
}

Total logic elements : 365
    Total combinational functions : 357
    Dedicated logic registers : 72
Total registers : 72

int queens(int N) {
    int count=0;
    int arow[32], aleft[32], aright[32], aposs[32];
    int    poss, place, val = (1<<N)-1, pos=1;
    arow[1]=aleft[1]=aright[1]=0;
    poss=aposs[1]=val>>(N/2);
    while(pos){
        if(poss){
            place = poss & -poss; 
            poss &= ~place;
            if(pos==1 && !poss && (N & 1))count<<=1;
            if(pos!=N){
                aposs[pos]=poss;
                poss=arow[pos+1]=arow[pos]|place;
                poss|=aleft[pos+1]=(aleft[pos]|place)<<1;
                poss|=aright[pos+1]=(aright[pos]|place)>>1;
                aposs[++pos]=poss=~(poss) & val;
            } else{
                ++count;
            }
        }else{
            poss=aposs[--pos];
        }
    }
    if(!(N & 1))count<<=1;
    return(count);
}
main(){
    int i, k;
    for(i=0;i<13;i++){
        k=queens(i);
        printf("f(%d)=%d\n",i,k);	
    }	
}