AMD AMD-K6-2/500AFX Data Sheet - Page 39
Branch Execution Unit, memory locations until all speculatively executed conditional
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21850J/0-February 2000 Preliminary Information AMD-K6®-2 Processor Data Sheet Branch Execution Unit The branch execution unit enables efficient speculative execution. This unit gives the processor the ability to execute instructions beyond conditional branches before knowing whether the branch prediction was correct. The AMD-K6-2 processor does not permanently update the x86 registers or memory locations until all speculatively executed conditional branch instructions are resolved. When a prediction is incorrect, the processor backs out to the point of the mispredicted branch instruction and restores all registers. The AMD-K6-2 processor can support up to seven outstanding branches. Chapter 2 Internal Architecture 19
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Chapter 2
Internal Architecture
19
21850J/0—February 2000
AMD-K6
®
-2 Processor Data Sheet
Preliminary Information
Branch Execution
Unit
The branch execution unit enables efficient speculative
execution. This unit gives the processor the ability to execute
instructions beyond conditional branches before knowing
whether the branch prediction was correct. The AMD-K6-2
processor does not permanently update the x86 registers or
memory locations until all speculatively executed conditional
branch instructions are resolved. When a prediction is
incorrect, the processor backs out to the point of the
mispredicted branch instruction and restores all registers. The
AMD-K6-2 processor can support up to seven outstanding
branches.