ali hagigat <hagigatali@xxxxxxxxx> writes: > Why two separate options have been considered for gcc, -mtune and > -march? I wonder if anybody can give an example application of using > these options while they are different. > By -mtune the code is optimized for one specific processor, what does > this optimization mean? gcc changes the assembly instructions > specified by -march and will turn them into the processor specified by > -mtune? > So why do we need -mtune? We can compile by -march from the beginning. The -mtune option mainly affects the instruction scheduler. That is, -march selects the set of instructions which the compiler will generate, and -mtune specifies the order in which they will appear. This makes a significant difference on some processors. Ian
