Method and system for processing branch instructions during emulation in

Abstract

A series of guest instructions including at least one guest branch instruction and other guest instructions are stored in memory. In addition, one or more semantic routines that are formed of native instructions and that may be utilized to emulate the series of guest instructions are stored in memory. For each other guest instruction in the series of guest instructions, an entry is stored in a multiple-entry queue in order of receipt of the other guest instructions. Each entry includes an indication of a location in memory of at least one semantic routine and a condition field indicating conditions that may be set or reset by the associated guest instruction. In response to the entries in the multiple-entry queue, the series of guest instructions are emulated in the processor by using the entries to access and execute selected ones of the one or more semantic routines. In response to detection of a conditional guest branch instruction in the series of guest instructions, a determination is made whether an entry in the multiple-entry queue associated with an instruction preceding the conditional guest branch instruction in the series has a condition field including an indication of a condition upon which the conditional branch instruction depends. If so, the indication is utilized to resolve the conditional guest branch instruction.