Loop optimization

[Walter Bright]

kai wrote:

> Here is a boiled down test case:
> 
> 	void main (string[] args)
> 	{
> 		double [] foo = new double [cast(int)1e6];
> 		for (int i=0;i<1e3;i++)
> 		{
> 			for (int j=0;j<1e6-1;j++)
> 			{
> 				foo[j]=foo[j]+foo[j+1];
> 			}
> 		}
> 	}
> 
> Any ideas?

for (int j=0;j<1e6-1;j++)

The j<1e6-1 is a floating point operation. It should be redone as an int one:
      j<1_000_000-1