MDN / store16_lane: Wasm SIMD load/store instruction
MDN / store16_lane: Wasm SIMD load/store instruction
The store16_lane SIMD load/store instruction stores a specified lane of a v128 i16x8 value interpretation at a given memory address.
(module
(import "console" "log" (func $log (param i32)))
(memory $memory 1)
(func $main
i32.const 0
v128.const i16x8 120 140 160 180 200 220 240 260
v128.store16_lane 7
i32.const 0
v128.load
i16x8.extract_lane_u 0
call $log
)
(start $main)
)
WebAssembly.instantiateStreaming(fetch("{%wasm-url%}"), { console });
Syntax
;; Common usage
v128.store16_lane lane_idx
;; With optional immediate operands
v128.store16_lane mem_idx offset=int align=int lane_idx
v128.store16_lane: The
v128.store16_laneinstruction.
mem_idx: An integer representing the memory index, in cases where the module uses multiple memories. The default is
0.
offset=int: An integer representing a constant number of bytes to add to the address before storing. The default is
0.
align=int: An integer representing a hint to the Wasm engine about what alignment to expect for the final address. The minimum value is
1and the default and maximum value is2. Analignvalue has to be a power of2.
lane_idx: The index of the lane whose value you want to store.
Type
[memory_address, input] -> []
memory_address: An integer representing the memory address to store the
inputat.
input: The
v128type from which to extract a lane value to store.
Binary encoding
InstructionBinary formatExample text => binaryv128.store16_lane0xfd 89:u32 mem_idx:u8 offset:u32 align:u32 l:laneidxv128.store16_lane 0 offset=0 align=2 7 => 0xfd 0x59 0x01 0x00 0x07While Wasm text format specifies the literal align value, the binary equivalent represents the exponent of the formula 2^x used to calculate the alignment. So for example, align=2 is equivalent to 0x01 (2^1).