Conditional branch instruction compaction for regional code size reduction

A computer program product for decreasing an execution time of a computer code, the computer program product comprising:

• one or more computer readable storage media and program instructions stored on the one or more computer readable storage media, the program instructions comprising:
• program instructions to identify a long-form conditional branch that is included in a first executed region of a computer code;
• program instructions to respond to a determination that the first executed region is executed frequently by determining whether the long-form conditional branch in the first executed region of the computer code is infrequently taken;
• and
• program instructions to respond to a determination that the long-form conditional branch is infrequently taken by initiating modification of the long-form conditional branch to be the short-form conditional branch by executing:
• program instructions to generate a long-form unconditional branch with a target that is a target of the long-form conditional branch;
• program instructions to modify the long-form conditional branch to be a short-form conditional branch;
• program instructions to insert the long-form unconditional branch into the computer code within a branch distance of the short-form conditional branch;
• and
• program instructions to modify a target of the short-form conditional branch to be a location of the long-form unconditional branch in the computer code.

A computer system for decreasing an execution time of a computer code, the computer system comprising:

• one or more computer processors;
• one or more computer readable storage media;
• and
• program instructions stored on the computer readable storage media for execution by at least one of the one or more processors, the program instructions comprising:
• program instructions to identify a long-form conditional branch that is included in a first executed region of a computer code;
• program instructions to respond to a determination that the first executed region is executed frequently by determining whether the long-form conditional branch in the first executed region of the computer code is infrequently taken;
• and
• program instructions to respond to a determination that the long-form conditional branch is infrequently taken by initiating modification of the long-form conditional branch to be the short-form conditional branch by executing:
• program instructions to generate a long-form unconditional branch with a target that is a target of the long-form conditional branch;
• program instructions to modify the long-form conditional branch to be a short-form conditional branch;
• program instructions to insert the long-form unconditional branch into the computer code within a branch distance of the short-form conditional branch;
• and
• program instructions to modify a target of the short-form conditional branch to be a location of the long-form unconditional branch in the computer code.