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Download Variable-Length Encoding (VLE) extension
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UM0438 A.5 Simplified mnemonics for VLE instructions Simplified mnemonics that incorporate the BO32 and BO16 operands The mnemonics in Table 18 allow common BO32 and BO16 operand encodings to be specified as part of the mnemonic, along with the set link register bit (LK). There are no simplified mnemonics for unconditional branches, branch to link register, and branch to count register. For these, the basic mnemonics e_b, e_bl, se_b, se_bl, se_blr, se_blrl, se_bctr, and se_bctrl are used. Table 18. Branch simplified mnemonics LR Update Not Enabled LR Update Enabled Branch semantics Branch if condition true Branch if condition false e_bc se_bc e_bcl e_bt se_bt e_btl e_bf se_bf e_bfl Decrement CTR, branch if CTR ≠ 0 (1) e_bdnz — e_bdnzl Decrement CTR, branch if CTR = 01 e_bdz — e_bdzl 1. Simplified mnemonics for branch instructions that do not test CR bits should specify only a target. Otherwise, a programming error may occur. Table 19 shows the syntax for basic simplified branch mnemonics Table 19. Branch instructions Instruction Branch Syntax e_b (e_bl) se_b (se_bl) target_addr e_bc (e_bcl) se_bc BO32,BI32,target_add r BO16,BI16,target_add r se_blr (se_blrl) — N/A, syntax does not include BO32 or BO16 se_bctr (se_bctrl) — N/A, syntax does not include BO32 or BO16 Branch Conditional Branch to Link Register Branch to Count Register Simplified mnemonic Standard mnemonic Syntax N/A, syntax does not include BO32 or BO16 e_bx(1) (e_bxl) se_bx1 BI32(2),target_addr BI16 2,target_addr 1. x stands for one of the symbols in Table 14 where applicable. 2. BI32 or BI16 can be a numeric value or an expression as shown in Table 17.. The simplified mnemonics in Table 18 that test a condition require a corresponding CR bit as the first operand (as the examples in Section A.5.1: Examples that eliminate the BO32 and BO16 operands below illustrate). The symbols in Table 17 can be used in place of a numeric value. A.5.1 Examples that eliminate the BO32 and BO16 operands The simplified mnemonics in Table 18 are used in the following examples: 31/50
