• -fstrength-reduce Perform the optimizations of loop strength reduction and elimination of iteration variables.

• -fthread-jumps Perform optimizations where we check to see if a jump branches to a location where another comparison subsumed by the first is found. If so, the first branch is redirected to either the destination of the second branch or a point immediately following it, depending on whether the condition is known to be true or false.

• -funroll-loops Perform the optimization of loop unrolling. This is only done for loops whose number of iterations can be determined at compile time or run time.

• -fcse-follow-jumps In common subexpression elimination, scan through jump instructions in certain cases. This is not as powerful as completely global CSE, but not as slow either.

• -frerun-cse-after-loop Re-run common subexpression elimination after loop optimizations has been performed.

• -fexpensive-optimizations Perform a number of minor optimizations that are relatively expensive.

• -fdelayed-branch If supported for the target machine, attempt to reorder instructions to exploit instruction slots available after delayed branch instructions.

• -fschedule-insns If supported for the target machine, attempt to reorder instructions to eliminate execution stalls due to required data being unavailable. This helps machines that have slow floating point or memory load instructions by allowing other instructions to be issued until the result of the load or floating point instruction is required.

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