Execution Timing
PowerPC e500 Core Family Reference Manual, Rev. 1
Freescale Semiconductor
4-19
Branch instructions are dispatched to the BIQ and are assigned a CQ slot, as shown in
Figure 4-6
.
Figure 4-6. Branch Completion (LR/CTR Write-Back)
In this example, the bc depends on cmp and is predicted as not taken. At the end of clock cycle 1,
cmp and bc are dispatched to the GIQ and BIQ, respectively, and are issued to SU1 and the BU at
the end of clock 2.
In clock cycle 3, the cmp executes in SU1 but the bc cannot resolve and complete until the cmp
results are available; add1 and add2 are dispatched to the GIQ.
In cycle 4, the bc resolves as correctly predicted; add1 and add2 are issued to the SUs and are
marked as nonspeculative, and add3 is dispatched to the GIQ. The cmp is retired from the CQ at
the end of cycle 4.
In cycle 5, bc, add1, and add2 finish execution, and bc and add1 retire.
Clock 1
Clock 2
Clock 3
Clock 4
Clock 5
IQ11
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IQ6
IQ5
IQ4
add3
IQ3
add2
IQ2
add1
add3
IQ1
bc
add2
IQ0
cmp
add1
add3
BIQ1
BIQ0
bc
GIQ3
GIQ2
GIQ1
add2
GIQ0
cmp
add1
add3
CQ13
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CQ6
CQ5
CQ4
CQ3
add2
add2 (SU2)
add3 (SU1)
CQ2
add1
add1 (SU1)
add2
√
CQ1
bc
bc (BU)
bc (BU)
add1
√
CQ0
cmp
cmp (SU1)
cmp
√
bc
√
√
indicates that the instruction has finished execution.
Содержание PowerPC e500 Core
Страница 1: ...PowerPC e500 Core Family Reference Manual Supports e500v1 e500v2 E500CORERM Rev 1 4 2005...
Страница 36: ...PowerPC e500 Core Family Reference Manual Rev 1 xxxvi Freescale Semiconductor...
Страница 38: ...PowerPC e500 Core Family Reference Manual Rev 1 Part I 2 Freescale Semiconductor...
Страница 316: ...PowerPC e500 Core Family Reference Manual Rev 1 7 18 Freescale Semiconductor Performance Monitor...
Страница 332: ...PowerPC e500 Core Family Reference Manual Rev 1 Part II 2 Freescale Semiconductor...
Страница 362: ...PowerPC e500 Core Family Reference Manual Rev 1 10 26 Freescale Semiconductor Auxiliary Processing Units APUs...
Страница 440: ...PowerPC e500 Core Family Reference Manual Rev 1 A 8 Freescale Semiconductor Programming Examples...
Страница 444: ...PowerPC e500 Core Family Reference Manual Rev 1 B 4 Freescale Semiconductor Guidelines for 32 Bit Book E...
Страница 530: ...Opcode Listings PowerPC e500 Core Family Reference Manual Rev 1 D 50 Freescale Semiconductor...
Страница 534: ...PowerPC e500 Core Family Reference Manual Rev 1 E 4 Freescale Semiconductor Revision History...