IBM powerpc 750gx User Manual

IBM

User’s Manual

IBM PowerPC 750GX and 750GL RISC Microprocessor

gx_03.fm.(1.2)
March 27, 2006

Instruction-Cache and Data-Cache Operation

Page 137 of 377

Figure 3-5. PLRU Replacement Algorithm

Replace

L0

Replace

L1

Replace

L2

Replace

L3

Replace

L4

Replace

L5

Replace

L6

Replace

L7

B0 = 0

B4 = 0

B1 = 0

B1 = 1

B2 = 1

B2 = 0

B0 = 1

B3 = 0

B3 = 1

B4 = 1

B5 = 0

B5 = 1

B6 = 0

B6 = 1

Allocate

L0

L0 invalid

Allocate

L2

L2 invalid

Allocate

L1

L1 invalid

Allocate

L3

L3 invalid

Allocate

L4

L4 invalid

Allocate

L5

L5 invalid

Allocate

L6

L6 invalid

Allocate

L7

L7 invalid

L7 valid

L0 valid

L1 valid

L2 valid

L3 valid

L4 valid

L5 valid

L6 valid