Parsing stack switching instructions in unfolded form. (#100)

This patch fixes problems with parsing the stack switching
instructions when they appear in unfolded form.

Author: dhil

interpreter/text/parser.mly

@@ -590,7 +590,7 @@ instr_list :
   | instr1 instr_list { fun c -> $1 c @ $2 c }
   | select_instr_instr_list { $1 }
   | call_instr_instr_list { $1 }
-  | resume_instr_instr { fun c -> let e, es = $1 c in e :: es }
+  | resume_instr_instr_list { $1 }
 
 instr1 :
   | plain_instr { fun c -> [$1 c @@ $sloc] }
@@ -768,25 +768,25 @@ call_instr_results_instr_list :
   | instr_list
     { fun c -> [], $1 c }
 
-resume_instr_instr :
+resume_instr_instr_list :
   | RESUME var resume_instr_handler_instr
     { let loc1 = $loc($1) in
       fun c ->
       let x = $2 c type_ in
-      let hs, es = $3 c in resume x hs @@ loc1, es }
+      let hs, es = $3 c in (resume x hs @@ loc1) :: es }
   | RESUME_THROW var var resume_instr_handler_instr
     { let loc1 = $loc($1) in
       fun c ->
       let x  = $2 c type_ in
       let tag = $3 c tag in
-      let hs, es = $4 c in resume_throw x tag hs @@ loc1, es }
+      let hs, es = $4 c in (resume_throw x tag hs @@ loc1) :: es }
 
 resume_instr_handler_instr :
   | LPAR ON var var RPAR resume_instr_handler_instr
     { fun c -> let hs, es = $6 c in ($3 c tag, OnLabel ($4 c label)) :: hs, es }
   | LPAR ON var SWITCH RPAR resume_instr_handler_instr
     { fun c -> let hs, es = $6 c in ($3 c tag, OnSwitch) :: hs, es }
-  | instr1
+  | instr_list
     { fun c -> [], $1 c }
 
 block_instr :

test/core/stack-switching/cont.wast

@@ -927,6 +927,112 @@
 )
 (assert_return (invoke "main") (i32.const 10))
 
+;; Syntax: check unfolded forms
+(module
+  (type $ft (func))
+  (type $ct (cont $ft))
+  (rec
+    (type $ft2 (func (param (ref null $ct2))))
+    (type $ct2 (cont $ft2)))
+
+  (tag $yield (param i32))
+  (tag $swap)
+
+  ;; Check cont.new
+  (func (result (ref $ct))
+    ref.null $ft
+    block (param (ref null $ft)) (result (ref $ct))
+      cont.new $ct
+    end
+  )
+  ;; Check cont.bind
+  (func (param (ref $ct)) (result (ref $ct))
+    local.get 0
+    block (param (ref $ct)) (result (ref $ct))
+      cont.bind $ct $ct
+    end
+  )
+  ;; Check suspend
+  (func
+    block
+      suspend $swap
+    end
+  )
+  ;; Check resume
+  (func (param $k (ref $ct)) (result i32)
+    (local.get $k)
+    block $on_yield (param (ref $ct)) (result i32 (ref $ct))
+      resume $ct (on $yield $on_yield)
+      i32.const 42
+      return
+    end
+    local.set $k
+  )
+  ;; Check resume_throw
+  (func (param $k (ref $ct)) (result i32)
+    block $on_yield (result i32 (ref $ct))
+      i32.const 42
+      local.get $k
+      resume_throw $ct $yield
+      i32.const 42
+      return
+    end
+    local.set $k
+  )
+  ;; Check switch
+  (func (param $k (ref $ct2))
+    local.get $k
+    block (param (ref $ct2)) (result (ref null $ct2))
+      switch $ct2 $swap
+    end
+    drop
+  )
+)
+
+;; Syntax: check instructions in tail position in unfolded form
+(module
+  (type $ft (func))
+  (type $ct (cont $ft))
+  (rec
+    (type $ft2 (func (param (ref null $ct2))))
+    (type $ct2 (cont $ft2)))
+
+  (tag $yield (param i32))
+  (tag $swap)
+
+  ;; Check cont.new
+  (func (result (ref $ct))
+    ref.null $ft
+    cont.new $ct
+  )
+  ;; Check cont.bind
+  (func (param (ref $ct)) (result (ref $ct))
+    local.get 0
+    cont.bind $ct $ct
+  )
+
+  ;; Check resume
+  (func (;2;) (param $k (ref $ct))
+    local.get $k
+    resume $ct
+  )
+  ;; Check resume_throw
+  (func (param $k (ref $ct))
+    i32.const 42
+    local.get $k
+    resume_throw $ct $yield
+  )
+  ;; Check switch
+  (func (param $k (ref $ct2)) (result (ref null $ct2))
+    local.get $k
+    switch $ct2 $swap
+  )
+  ;; Check suspend
+  (func
+    suspend $swap
+  )
+)
+
 (module
   (type $ft0 (func))
   (type $ct0 (cont $ft0))
@@ -960,4 +1066,4 @@
 
     (func (param $k (ref $ct))
       (switch $ct $t)))
-  "type mismatch in switch tag")
+  "type mismatch in switch tag")