초록 ▼

A microprocessor for efficient processing of instructions in a program flow including a conditional program flow control instruction, such as a branch instruction. The conditional program flow control instruction targets a first code section to be processed if the condition is resolved to be met, an

A microprocessor for efficient processing of instructions in a program flow including a conditional program flow control instruction, such as a branch instruction. The conditional program flow control instruction targets a first code section to be processed if the condition is resolved to be met, and a second code section to be processed if the condition is resolved to be not met. A fetch unit fetches instructions to be processed and branch prediction logic coupled to the fetch unit predicts the resolution of the condition. The branch prediction logic of the invention also determines whether resolution of the condition is unlikely to be predicted accurately. Stream management logic responsive to the branch prediction logic directs speculative processing of instructions from both the first and second code sections prior to resolution of the condition if resolution of the condition is unlikely to be predicted accurately. Results of properly executed instructions are then committed to architectural state in program order. In this manner, the invention reduces the performance penalty related to mispredictions.

대표청구항 ▼

[ We claim:] [1.] A processor comprising:branch prediction logic to identify whether resolution of a condition corresponding to a first conditional program flow control instruction is unlikely to be predicted accurately, the first conditional program flow control instruction indicating a first code

[ We claim:] [1.] A processor comprising:branch prediction logic to identify whether resolution of a condition corresponding to a first conditional program flow control instruction is unlikely to be predicted accurately, the first conditional program flow control instruction indicating a first code section to be executed if the condition is resolved to be met, a second code section to be executed if the condition is resolved to be not met; andstream management logic responsive to the branch prediction logic to cause speculative processing of both the first and second code sections prior to resolution of the condition if the branch prediction logic indicates that the condition is unlikely to be predicted accurately.