[wasm-split] Add an --asyncify option (#4513)

Add an option for running the asyncify transformation on the primary module
emitted by wasm-split. The idea is that the placeholder functions should be able
to unwind the stack while the secondary module is asynchronously loaded, then
once the placeholder functions have been patched out by the secondary module the
stack should be rewound and end up in the correct secondary function.

1 files changed, 174 insertions, 0 deletions

diff --git a/test/lit/wasm-split/asyncify.wast b/test/lit/wasm-split/asyncify.wast
new file mode 100644
index 000000000..4894f58a7
--- /dev/null
+++ b/test/lit/wasm-split/asyncify.wast
@@ -0,0 +1,174 @@
+;; RUN: wasm-split %s --export-prefix='%' -g -o1 %t.1.wasm -o2 %t.2.wasm --keep-funcs=foo --asyncify
+;; RUN: wasm-dis %t.1.wasm | filecheck %s --check-prefix PRIMARY
+;; RUN: wasm-dis %t.2.wasm | filecheck %s --check-prefix SECONDARY
+
+;; Check that the --asyncify option instruments the primary module but not the
+;; secondary module.
+
+(module
+ (func $foo (param i32) (result i32)
+  (call $bar (i32.const 0))
+ )
+ (func $bar (param i32) (result i32)
+  (call $foo (i32.const 1))
+ )
+)
+
+;; PRIMARY:      (module
+;; PRIMARY-NEXT:  (type $i32_=>_i32 (func (param i32) (result i32)))
+;; PRIMARY-NEXT:  (type $i32_=>_none (func (param i32)))
+;; PRIMARY-NEXT:  (type $none_=>_none (func))
+;; PRIMARY-NEXT:  (type $none_=>_i32 (func (result i32)))
+;; PRIMARY-NEXT:  (import "placeholder" "0" (func $placeholder_0 (param i32) (result i32)))
+;; PRIMARY-NEXT:  (global $global$0 (mut i32) (i32.const 0))
+;; PRIMARY-NEXT:  (global $global$1 (mut i32) (i32.const 0))
+;; PRIMARY-NEXT:  (memory $0 1 1)
+;; PRIMARY-NEXT:  (table $0 1 funcref)
+;; PRIMARY-NEXT:  (elem (i32.const 0) $placeholder_0)
+;; PRIMARY-NEXT:  (export "%foo" (func $foo))
+;; PRIMARY-NEXT:  (export "%table" (table $0))
+;; PRIMARY-NEXT:  (export "asyncify_start_unwind" (func $asyncify_start_unwind))
+;; PRIMARY-NEXT:  (export "asyncify_stop_unwind" (func $asyncify_stop_unwind))
+;; PRIMARY-NEXT:  (export "asyncify_start_rewind" (func $asyncify_start_rewind))
+;; PRIMARY-NEXT:  (export "asyncify_stop_rewind" (func $asyncify_stop_rewind))
+;; PRIMARY-NEXT:  (export "asyncify_get_state" (func $asyncify_get_state))
+;; PRIMARY-NEXT:  (func $foo (param $0 i32) (result i32)
+;; PRIMARY-NEXT:   (local $1 i32)
+;; PRIMARY-NEXT:   (if
+;; PRIMARY-NEXT:    (i32.eq
+;; PRIMARY-NEXT:     (global.get $global$0)
+;; PRIMARY-NEXT:     (i32.const 2)
+;; PRIMARY-NEXT:    )
+;; PRIMARY-NEXT:    (block
+;; PRIMARY-NEXT:     (i32.store
+;; PRIMARY-NEXT:      (global.get $global$1)
+;; PRIMARY-NEXT:      (i32.sub
+;; PRIMARY-NEXT:       (i32.load
+;; PRIMARY-NEXT:        (global.get $global$1)
+;; PRIMARY-NEXT:       )
+;; PRIMARY-NEXT:       (i32.const 4)
+;; PRIMARY-NEXT:      )
+;; PRIMARY-NEXT:     )
+;; PRIMARY-NEXT:     (local.set $0
+;; PRIMARY-NEXT:      (i32.load
+;; PRIMARY-NEXT:       (i32.load
+;; PRIMARY-NEXT:        (global.get $global$1)
+;; PRIMARY-NEXT:       )
+;; PRIMARY-NEXT:      )
+;; PRIMARY-NEXT:     )
+;; PRIMARY-NEXT:    )
+;; PRIMARY-NEXT:   )
+;; PRIMARY-NEXT:   (local.set $1
+;; PRIMARY-NEXT:    (block $label$2 (result i32)
+;; PRIMARY-NEXT:     (if
+;; PRIMARY-NEXT:      (i32.eqz
+;; PRIMARY-NEXT:       (select
+;; PRIMARY-NEXT:        (if (result i32)
+;; PRIMARY-NEXT:         (i32.eq
+;; PRIMARY-NEXT:          (global.get $global$0)
+;; PRIMARY-NEXT:          (i32.const 2)
+;; PRIMARY-NEXT:         )
+;; PRIMARY-NEXT:         (block (result i32)
+;; PRIMARY-NEXT:          (i32.store
+;; PRIMARY-NEXT:           (global.get $global$1)
+;; PRIMARY-NEXT:           (i32.sub
+;; PRIMARY-NEXT:            (i32.load
+;; PRIMARY-NEXT:             (global.get $global$1)
+;; PRIMARY-NEXT:            )
+;; PRIMARY-NEXT:            (i32.const 4)
+;; PRIMARY-NEXT:           )
+;; PRIMARY-NEXT:          )
+;; PRIMARY-NEXT:          (i32.load
+;; PRIMARY-NEXT:           (i32.load
+;; PRIMARY-NEXT:            (global.get $global$1)
+;; PRIMARY-NEXT:           )
+;; PRIMARY-NEXT:          )
+;; PRIMARY-NEXT:         )
+;; PRIMARY-NEXT:         (local.get $1)
+;; PRIMARY-NEXT:        )
+;; PRIMARY-NEXT:        (i32.const 0)
+;; PRIMARY-NEXT:        (global.get $global$0)
+;; PRIMARY-NEXT:       )
+;; PRIMARY-NEXT:      )
+;; PRIMARY-NEXT:      (block
+;; PRIMARY-NEXT:       (local.set $1
+;; PRIMARY-NEXT:        (call_indirect (type $i32_=>_i32)
+;; PRIMARY-NEXT:         (i32.const 0)
+;; PRIMARY-NEXT:         (i32.const 0)
+;; PRIMARY-NEXT:        )
+;; PRIMARY-NEXT:       )
+;; PRIMARY-NEXT:       (drop
+;; PRIMARY-NEXT:        (br_if $label$2
+;; PRIMARY-NEXT:         (i32.const 0)
+;; PRIMARY-NEXT:         (i32.eq
+;; PRIMARY-NEXT:          (global.get $global$0)
+;; PRIMARY-NEXT:          (i32.const 1)
+;; PRIMARY-NEXT:         )
+;; PRIMARY-NEXT:        )
+;; PRIMARY-NEXT:       )
+;; PRIMARY-NEXT:       (local.set $0
+;; PRIMARY-NEXT:        (local.get $1)
+;; PRIMARY-NEXT:       )
+;; PRIMARY-NEXT:      )
+;; PRIMARY-NEXT:     )
+;; PRIMARY-NEXT:     (if
+;; PRIMARY-NEXT:      (i32.eqz
+;; PRIMARY-NEXT:       (global.get $global$0)
+;; PRIMARY-NEXT:      )
+;; PRIMARY-NEXT:      (return
+;; PRIMARY-NEXT:       (local.get $0)
+;; PRIMARY-NEXT:      )
+;; PRIMARY-NEXT:     )
+;; PRIMARY-NEXT:     (unreachable)
+;; PRIMARY-NEXT:    )
+;; PRIMARY-NEXT:   )
+;; PRIMARY-NEXT:   (i32.store
+;; PRIMARY-NEXT:    (i32.load
+;; PRIMARY-NEXT:     (global.get $global$1)
+;; PRIMARY-NEXT:    )
+;; PRIMARY-NEXT:    (local.get $1)
+;; PRIMARY-NEXT:   )
+;; PRIMARY-NEXT:   (i32.store
+;; PRIMARY-NEXT:    (global.get $global$1)
+;; PRIMARY-NEXT:    (i32.add
+;; PRIMARY-NEXT:     (i32.load
+;; PRIMARY-NEXT:      (global.get $global$1)
+;; PRIMARY-NEXT:     )
+;; PRIMARY-NEXT:     (i32.const 4)
+;; PRIMARY-NEXT:    )
+;; PRIMARY-NEXT:   )
+;; PRIMARY-NEXT:   (i32.store
+;; PRIMARY-NEXT:    (i32.load
+;; PRIMARY-NEXT:     (global.get $global$1)
+;; PRIMARY-NEXT:    )
+;; PRIMARY-NEXT:    (local.get $0)
+;; PRIMARY-NEXT:   )
+;; PRIMARY-NEXT:   (i32.store
+;; PRIMARY-NEXT:    (global.get $global$1)
+;; PRIMARY-NEXT:    (i32.add
+;; PRIMARY-NEXT:     (i32.load
+;; PRIMARY-NEXT:      (global.get $global$1)
+;; PRIMARY-NEXT:     )
+;; PRIMARY-NEXT:     (i32.const 4)
+;; PRIMARY-NEXT:    )
+;; PRIMARY-NEXT:   )
+;; PRIMARY-NEXT:   (i32.const 0)
+;; PRIMARY-NEXT:  )
+;; PRIMARY:       (func $asyncify_start_unwind (param $0 i32)
+;; PRIMARY:       (func $asyncify_stop_unwind
+;; PRIMARY:       (func $asyncify_start_rewind (param $0 i32)
+;; PRIMARY:       (func $asyncify_stop_rewind
+;; PRIMARY:       (func $asyncify_get_state (result i32)
+;; PRIMARY:      )
+
+;; SECONDARY:      (module
+;; SECONDARY-NEXT:  (type $i32_=>_i32 (func (param i32) (result i32)))
+;; SECONDARY-NEXT:  (import "primary" "%table" (table $timport$0 1 funcref))
+;; SECONDARY-NEXT:  (import "primary" "%foo" (func $foo (param i32) (result i32)))
+;; SECONDARY-NEXT:  (elem (i32.const 0) $bar)
+;; SECONDARY-NEXT:  (func $bar (param $0 i32) (result i32)
+;; SECONDARY-NEXT:   (call $foo
+;; SECONDARY-NEXT:    (i32.const 1)
+;; SECONDARY-NEXT:   )
+;; SECONDARY-NEXT:  )
+;; SECONDARY-NEXT: )