br_table: Wasm-Textanweisung

(module
 ;; Import the browser console object, which you'll need to pass in from JavaScript
 (import "console" "log" (func $log (param i32)))
 (func
 ;; Label each block for easy reference
 ;; (they can also be referenced by their index)
 (block $outer_block
 (block $middle_block
 (block $inner_block
 ;; Choose which block to break out of based on their order in the br_table
 ;; 0 is `$inner_block`, 1 is `$outer_block`, 2 is `$middle_block`
 i32.const 0
 ;; Create a br_table with three targets
 (br_table $inner_block $outer_block $middle_block)
 ;; The code will never reach this point since we broke out of the block
 unreachable
 )
 ;; If you jump out of `$inner_block` but stay in `$middle_block`,
 ;; 42 will be logged
 ;; If you jump out of `$middle_block` also,
 ;; by jumping out of either `$middle_block` or `$outer_block`,
 ;; this will be skipped
 i32.const 42
 call $log
 )
 )
 )
 (start 1) ;; Run the first function automatically
)

const url = "{%wasm-url%}";
await WebAssembly.instantiateStreaming(fetch(url), { console });

;; Add true to the top of the stack so that the `if` statement is executed.
i32.const 1
(if ;; 2
 (then
 (block ;; 1
 (loop ;; 0
 ;; Add a variable to the top of the stack
 i32.const 2
 ;; 0 = jump to `block`; since item 0 in br_table is 1, it jumps up one level
 ;; 1 = jump to `if`; since item 1 in br_table is 2, it jumps up two levels
 ;; 2 = jump to `loop`; since item 2 in br_table is 0, it doesn't jump any levels (causing an infinite loop)
 ;; Create a br_table with the targets
 (br_table 1 2 0)
 )
 )
 )
)

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