RISC-V ISA Explorer · Bit Manipulation (Zb*)

Zba: Address-Generation Bitmanip

Ratified 2021-06 · version 1.0.0

Shift-and-add instructions that compute an array element address in one operation instead of several.

Typical use: Array indexing and pointer arithmetic

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Dependencies

Required by

B

Instructions (8)

Mnemonic	Name	Encoding	Match	Mask
`ADD.UW`	Add unsigned word	`0000100----------000-----0111011`	`0x800003b`	`0xfe00707f`
`SH1ADD`	Shift left by 1 and add	`0010000----------010-----0110011`	`0x20002033`	`0xfe00707f`
`SH1ADD.UW`	Shift unsigned word left by 1 and add	`0010000----------010-----0111011`	`0x2000203b`	`0xfe00707f`
`SH2ADD`	Shift left by 2 and add	`0010000----------100-----0110011`	`0x20004033`	`0xfe00707f`
`SH2ADD.UW`	Shift unsigned word left by 2 and add	`0010000----------100-----0111011`	`0x2000403b`	`0xfe00707f`
`SH3ADD`	Shift left by 3 and add	`0010000----------110-----0110011`	`0x20006033`	`0xfe00707f`
`SH3ADD.UW`	Shift unsigned word left by 3 and add	`0010000----------110-----0111011`	`0x2000603b`	`0xfe00707f`
`SLLI.UW`	Shift left unsigned word (Immediate)	`000010-----------001-----0011011`	`0x800101b`	`0xfc00707f`