1. At a computer system, the computer system including a processor and system memory, the computer system also including a compiler and a runtime, the compiler configured to compile statements and expressions of higher level source code into representative lower level instructions of lower level code, the runtime configured to execute executable code, a method for binding code at runtime to improve performance, the method comprising: an act of accessing statements and expressions of higher level source code; an act of detecting that the higher level source code includes at least one specified aspect for which the execution efficiency of corresponding representative lower instructions varies to a requisite extent dependent upon the configuration of input data received during execution; an act of compiling the statements and expressions of the accessed higher level source code into representative lower level instructions of the lower level code, including: an act of compiling a plurality of different representative lower level instructions for the at least one specified aspect, each of the plurality of different representative lower level instructions configured to correctly implement the intent of the at least one specified aspect, at least one of the plurality of different representative lower level instructions being optimized for execution efficiency based on a different configuration of received input data; an act of configuring execution of the lower level instructions at runtime, including: an act of analyzing the configuration of input data to be provided to the at least one specified aspect of the higher level source code; an act of determining that specified representative lower level instructions, selected from among the plurality of different representative lower level instructions, are optimized for execution based on the configuration of the provided input data; and an act of binding the specified lower level instructions to executable code to implement the intent of the at least one specified aspect of the higher level source code.