AN2491 Freescale Semiconductor / Motorola, AN2491 Datasheet

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... Freescale Semiconductor, Inc. Application Note AN2491 Rev. 0, 9/2003 Simplified Mnemonics for PowerPC™ Instructions Simplified Mnemonics for PowerPC™ Instructions Jerry Young, NCSD Applications This document describes simplified mnemonics, which are provided for easier coding of assembly language programs. Simplified mnemonics are defined for the most frequently used forms of branch conditional, compare, trap, rotate and shift, and certain other instructions defined by the PowerPC™ ...

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Freescale Semiconductor, Inc. Overview Overview 1 Overview Simplified (or extended) mnemonics allow an assembly-language programmer to program using more intuitive mnemonics and symbols than the instructions and syntax defined by the instruction set architecture. For example, to code the conditional ...

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Freescale Semiconductor, Inc. 3 Rotate and Shift Simplified Mnemonics Rotate and shift instructions provide powerful, general ways to manipulate register contents, but can be difficult to understand. Simplified mnemonics are provided for the following operations: • Extract—Select a field of ...

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Freescale Semiconductor, Inc. Branch Instruction Simplified Mnemonics Branch Instruction Simplified Mnemonics 4 Branch Instruction Simplified Mnemonics Branch conditional instructions can be coded with the operations, a condition to be tested, and a prediction, as part of the instruction mnemonic rather ...

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Freescale Semiconductor, Inc. 4.1 Key Facts about Simplified Branch Mnemonics The following key points are helpful in understanding how to use simplified branch mnemonics: • All simplified branch mnemonics eliminate the BO operand any operand is present in ...

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Freescale Semiconductor, Inc. Branch Instruction Simplified Mnemonics Branch Instruction Simplified Mnemonics Thus encoding of 10100 (decimal 20) means ignore the CR bit comparison and do not decrement the CTR—in other words, branch unconditionally. Encodings for the BO operand ...

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Freescale Semiconductor, Inc. For relative and absolute branches (bc[l][a]), the setting of the y bit depends on whether the displacement field is negative or non-negative. For negative displacement fields, coding the suffix ‘+’ causes the bit to be cleared, and ...

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Freescale Semiconductor, Inc. Branch Instruction Simplified Mnemonics Branch Instruction Simplified Mnemonics Simplified mnemonics based on CR conditions but not CTR values— (branch if true) and branch if false) Standard branch mnemonics and simplified mnemonics based ...

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Freescale Semiconductor, Inc. Table 8. BI Operand Settings for CR Fields for Branch Comparisons CRn Bit Expression AIM (BI Bit Operand) CRn[ cr0 + lt (or lt cr1 + cr2 + lt 4 ...

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Freescale Semiconductor, Inc. Branch Instruction Simplified Mnemonics Branch Instruction Simplified Mnemonics Table 9. CR Field Identification Symbols (continued) To identify a CR bit, an expression in which a CR field symbol is multiplied by 4 and then added to a ...

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Freescale Semiconductor, Inc. Table 11 shows the syntax for basic simplified branch mnemonics Instruction Branch Branch Conditional Branch Conditional to Link Register Branch Conditional to Count Register 1 x stands for one of the symbols in Table 6, where applicable. ...

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Freescale Semiconductor, Inc. Branch Instruction Simplified Mnemonics Branch Instruction Simplified Mnemonics Table 12. Simplified Mnemonics for bc and bca without LR Update (continued) Branch Semantics 1 Branch if condition false Decrement CTR, branch if CTR 0 Decrement CTR, branch if ...

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Freescale Semiconductor, Inc. Table 14 provides simplified mnemonics and syntax for bcl and bcla. Table 14. Simplified Mnemonics for bcl and bcla with LR Update Branch Semantics Branch unconditionally 1 Branch if condition true 1 Branch if condition false Decrement ...

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Freescale Semiconductor, Inc. Branch Instruction Simplified Mnemonics Branch Instruction Simplified Mnemonics 4.6 Simplified Mnemonics that Incorporate CR Conditions (Eliminates BO and Replaces BI with crS) The mnemonics in Table 18 are variations of the branch-if-condition-true (BO = 12) and branch-if-condition-false ...

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Freescale Semiconductor, Inc. Table 17. Branch Instructions and Simplified Mnemonics that Incorporate CR Conditions Instruction Branch Branch Conditional Branch Conditional to Link Register Branch Conditional to Count Register 1 x stands for one of the symbols in Table 16, where ...

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Freescale Semiconductor, Inc. Branch Instruction Simplified Mnemonics Branch Instruction Simplified Mnemonics 3. Branch to an absolute target if CR4 specifies greater than condition, setting the LR. This is a form of conditional call. bgtla cr4,target 4. Same as (3), but ...

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Freescale Semiconductor, Inc. Table 20. Simplified Mnemonics for bclr and bcctr without Comparison Conditions and LR Updating (continued) Branch Semantics Branch if greater than bclr 12,BI Branch if not equal bclr 4,BI Branch if summary overflow bclr 12,BI Branch if ...

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Freescale Semiconductor, Inc. Compare Word Simplified Mnemonics Compare Word Simplified Mnemonics Table 22 shows the simplified branch mnemonics and syntax for bclrl and bcctrl with LR updating. Table 22. Simplified Mnemonics for bclrl and bcctrl with Comparison Conditions and LR ...

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Freescale Semiconductor, Inc. 6 Condition Register Logical Simplified Mnemonics The CR logical instructions, shown in Table 24, can be used to set, clear, copy, or invert a given CR bit. Simplified mnemonics allow these operations to be coded easily. Note ...

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Freescale Semiconductor, Inc. Trap Instructions Simplified Mnemonics Trap Instructions Simplified Mnemonics Table 25. Standard Codes for Trap Instructions (continued) Code Description lge Logically greater than or equal lgt Logically greater than lnl Logically not less than lng Logically not greater ...

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Freescale Semiconductor, Inc. 4. Trap unconditionally. trap Trap instructions evaluate a trap condition as follows: The contents of rA are compared with either the sign-extended SIMM field or the contents of rB, depending on the trap instruction. The comparison results ...

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Freescale Semiconductor, Inc. AltiVec Simplified Mnemonics AltiVec Simplified Mnemonics Table 28. Additional Simplified Mnemonics for Accessing IBATs, DBATs, and SPRGs Move to SPR SPR Simplified Mnemonic DBAT register, mtdbatl n,rS lower mtdbatln,rS DBAT register, mtdbatu n,rS lower mtdbatun,rS IBAT register, ...

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Freescale Semiconductor, Inc. 10 Recommended Simplified Mnemonics This section describes commonly-used operations (such as no-op, load immediate, load address, move register, and complement register). 10.1 No-Op (nop) Many instructions can be coded in such a way that, effectively, no operation ...

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Freescale Semiconductor, Inc. EIS-Specific Simplified Mnemonics EIS-Specific Simplified Mnemonics 10.5 Complement Register (not) Several instructions can be coded in such a way that they complement the contents of one register and place the result into another register. A simplified mnemonic ...

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Freescale Semiconductor, Inc. 12 Comprehensive List of Simplified Mnemonics Table 31 lists simplified mnemonics. Note that compiler designers may implement additional simplified mnemonics not listed here. Simplified Mnemonic 1 bctr 1 bctrl 1 bdnz target 1 bdnza target bdnzf BI,target ...

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Freescale Semiconductor, Inc. Comprehensive List of Simplified Mnemonics Comprehensive List of Simplified Mnemonics Table 31. Simplified Mnemonics (continued) Simplified Mnemonic bdnztlr BI bdnztlrl BI 1 bdz target 1 bdza target bdzf BI,target bdzfa BI,target bdzfl BI,target bdzfla BI,target bdzflr BI ...

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Freescale Semiconductor, Inc. Table 31. Simplified Mnemonics (continued) Simplified Mnemonic beqctr crS,target beqctrl crS,target bcctrl 12,BI beql crS,target beqla crS,target beqlr crS,target beqlrl crS,target bf BI,target bfa BI,target bfctr BI bfctrl BI bfl BI,target bfla BI,target bflr BI bflrl BI ...

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Freescale Semiconductor, Inc. Comprehensive List of Simplified Mnemonics Comprehensive List of Simplified Mnemonics Table 31. Simplified Mnemonics (continued) Simplified Mnemonic bgta crS,target bgtctr crS,target bgtctrl crS,target bcctrl 12,BI bgtl crS,target bgtla crS,target bgtlr crS,target bgtlrl crS,target ble crS,target blea crS,target ...

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Freescale Semiconductor, Inc. Comprehensive List of Simplified Mnemonics Comprehensive List of Simplified Mnemonics Table 31. Simplified Mnemonics (continued) Simplified Mnemonic bltl crS,target bltla crS,target bltlr crS,target bltlrl crS,target bne crS,target bnea crS,target bnectr crS,target bnectrl crS,target bnel crS,target bnela crS,target ...

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Freescale Semiconductor, Inc. Comprehensive List of Simplified Mnemonics Comprehensive List of Simplified Mnemonics Table 31. Simplified Mnemonics (continued) Simplified Mnemonic bnla crS,target bnlctr crS,target bnlctrl crS,target bnll crS,target bnlla crS,target bnllr crS,target bnllrl crS,target bns crS,target bnsa crS,target bnsctr crS,target ...

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Freescale Semiconductor, Inc. Comprehensive List of Simplified Mnemonics Comprehensive List of Simplified Mnemonics Table 31. Simplified Mnemonics (continued) Simplified Mnemonic bnulr crS,target bnulrl crS,target bso crS,target bsoa crS,target bsoctr crS,target bsoctrl crS,target bcctrl 12,BI bsol crS,target bsola crS,target bsolr crS,target ...

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Freescale Semiconductor, Inc. Comprehensive List of Simplified Mnemonics Comprehensive List of Simplified Mnemonics Table 31. Simplified Mnemonics (continued) Simplified Mnemonic bunlr crS,target bunlrl crS,target clrlslwi rA,rS,b 31) rlwinm rA,rS,n,b – n,31 – n clrlwi rA,rS,n (n < 32) ...

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Freescale Semiconductor, Inc. Comprehensive List of Simplified Mnemonics Comprehensive List of Simplified Mnemonics Table 31. Simplified Mnemonics (continued) Simplified Mnemonic mtspr rS nop not rA,rS not rA,rS rotlw rA,rS,rB rlwnm rA,rS,rB,0,31 rotlwi rA,rS,n rlwinm rA,rS,n,0,31 rotrwi rA,rS,n rlwinm rA,rS,32 – ...

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Freescale Semiconductor, Inc. Comprehensive List of Simplified Mnemonics Comprehensive List of Simplified Mnemonics Table 31. Simplified Mnemonics (continued) Simplified Mnemonic twlnl rA,SIMM twlnli rA,SIMM twlt rA,SIMM twlti rA,SIMM twne rA,SIMM twnei rA,SIMM twng rA,SIMM twngi rA,SIMM twnl rA,SIMM twnli rA,SIMM ...

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Freescale Semiconductor, Inc. Comprehensive List of Simplified Mnemonics Comprehensive List of Simplified Mnemonics THIS PAGE INTENTIONALLY LEFT BLANK 35 Simplified Mnemonics for PowerPC™ Instructions For More Information On This Product, Go to: www.freescale.com MOTOROLA ...

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... Motorola, Inc. The PowerPC name is a trademark of IBM Corp. and is used under license. All other product or service names are the property of their respective owners. Motorola, Inc Equal Opportunity/Affirmative Action Employer. © Motorola, Inc. 2003 AN2491 For More Information On This Product, Go to: www.freescale.com ...