A method and system for partial connection of iterations during loop unrolling during compilation of a program by a compiler. Unrolled loop iterations of a loop in the program are selectively connected, including redirecting, to the head of the loop, undesirable edges of a control flow from one iteration to a next iteration of the loop. Merges on a path of hot code are removed to increase a scope for optimization of the program. The head of the loop and a start of a replicated loop body of the loop are equivalent points of the control flow. A sequence of blocks on the path of hot code, unpolluted by a control flow of a path of cold code, is extended during the compilation. Information computed by an optimizer about the hot code in a first iteration is used to further optimize a second iteration, and the loop is further unrolled.