Tlb Management Instructions; Processor Management Instructions; Extended Mnemonics; Table 3-34. Tlb Management Instructions - IBM PowerPC 405GP User Manual

Embedded processor
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3.11.8
TLB
Management Instructions
The TLB management instructions read and write entries of the TLB array in the MMU, search the
TLB array for an entry which will translate a given address, and invalidate all TLB entries. There is
also an instruction for synchronizing TLB updates with other processors, but because the PPC405GP
is for use in uniprocessor environments, this instruction performs no operation.
Table 3-34 lists the TLB management instructions. In the table, the syntax "[.]" indicates that the
instruction has a "record" form that updates CR[CRO], and a "non-record" form.
Table 3-34. TLB Management Instructions
tibia
tlbre
tlbsx[.]
tlbsync
tlbwe
3.11.9 Processor Management Instructions
These instructions move data between the GPRs and SPRs, the CR, and DCRs in the PPC405GP,
and provide traps, system calls, and synchronization controls.
Table 3-35 lists the processor management instructions in the PPC405GP.
Table 3-35. Processor Management Instructions
elelo
mcrxr
mtcrf
Isync
mfcr
mtdcr
sync
mfdcr
mtspr
mfspr
sc
tw
twl
3.11.10 Extended Mnemonics
In addition to mnemonics for instructions supported directly by hardware, the PowerPC Architecture
defines numerous extended mnemonics.
An extended mnemonic translates directly into the mnemonic; of a hardware instruction, typically with
carefully specified operands. For example, the PowerPC Architecture does not define a "shift right
word immediate" instruction, because the "rotate left word imm'ediate then AND with mask:' (rlwinm)
instruction can accomplish the same result:
rlwinm RA,RS,32-n,n,31
However, because the required operands are not obvious, the PowerPC Architecture defines an
extended mnemonic:
srwi RA,RS,n
Extended mnemonics transfer the problem of remembering complex or frequently used operand
combinations to the assembler, and can more clearly reflect a programmer's intentions. Thus,
programs can be more readable.
Refer to the following chapter and appendixes for lists of the extended mnemonics:
Preliminary
Programming Model
3-53

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