Forbid mixing context types within a component

crates/wasmparser/src/validator/component.rs

@@ -169,6 +169,10 @@ pub(crate) struct ComponentState {
 
     /// Same as `toplevel_exported_resources`, but for imports.
     toplevel_imported_resources: ComponentNameContext,
+
+    /// The type that's been assigned to slots of `context.{get,set}` by this
+    /// component. This is `None` until the first intrinsic is seen.
+    context_type: Option<ValType>,
 }
 
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
@@ -462,6 +466,7 @@ impl ComponentState {
             imported_types: Default::default(),
             toplevel_exported_resources: Default::default(),
             toplevel_imported_resources: Default::default(),
+            context_type: None,
         }
     }
 
@@ -1559,20 +1564,33 @@ impl ComponentState {
         Ok(())
     }
 
-    fn validate_context_type(&self, ty: ValType, intrinsic: &str, offset: usize) -> Result<()> {
+    fn validate_context_type(&mut self, ty: ValType, intrinsic: &str, offset: usize) -> Result<()> {
         match ty {
-            ValType::I32 => Ok(()),
+            ValType::I32 => {}
             ValType::I64 => {
                 if !self.features.cm64() {
                     bail!(
                         offset,
                         "64-bit `{intrinsic}` requires the component model 64-bit feature"
                     )
                 }
-                Ok(())
+                {}
             }
             _ => bail!(offset, "`{intrinsic}` only supports `i32` or `i64`"),
         }
+
+        match self.context_type {
+            None => self.context_type = Some(ty),
+            Some(other) => {
+                if other != ty {
+                    bail!(
+                        offset,
+                        "`{intrinsic}` type must match previous context type"
+                    )
+                }
+            }
+        }
+        Ok(())
     }
 
     fn thread_yield(&mut self, types: &mut TypeAlloc, offset: usize) -> Result<()> {

tests/cli/component-model/async/threading-and-memory64.wast

@@ -0,0 +1,15 @@
+;; RUN: wast --assert default --snapshot tests/snapshots % -f cm-async,cm-threading,cm64
+
+(assert_invalid
+  (component
+    (core func (canon context.set i32 0))
+    (core func (canon context.get i64 1))
+  )
+  "type must match previous context type")
+
+(assert_invalid
+  (component
+    (core func (canon context.get i64 0))
+    (core func (canon context.set i32 1))
+  )
+  "type must match previous context type")

tests/cli/component-model/memory64/context.wast

@@ -18,12 +18,28 @@
   ))
 )
 
-;; Mixed i32 and i64 slots round-trip independently.
+;; can't mix i32/i64
+(assert_invalid
+  (component
+    (core func (canon context.get i32 0))
+    (core func (canon context.set i64 0))
+  )
+  "type must match previous context type")
+(assert_invalid
+  (component
+    (core func (canon context.set i64 0))
+    (core func (canon context.get i32 0))
+  )
+  "type must match previous context type")
+
+;; can mix across components
 (component
-  (core func (canon context.get i32 0))
-  (core func (canon context.set i32 0))
-  (core func (canon context.get i64 0))
-  (core func (canon context.set i64 0))
+  (component
+    (core func (canon context.set i64 0))
+  )
+  (component
+    (core func (canon context.get i32 0))
+  )
 )
 
 ;; Signature must match the declared slot width.

tests/snapshots/cli/component-model/async/threading-and-memory64.wast.json

@@ -0,0 +1,19 @@
+{
+  "source_filename": "tests/cli/component-model/async/threading-and-memory64.wast",
+  "commands": [
+    {
+      "type": "assert_invalid",
+      "line": 4,
+      "filename": "threading-and-memory64.0.wasm",
+      "module_type": "binary",
+      "text": "type must match previous context type"
+    },
+    {
+      "type": "assert_invalid",
+      "line": 11,
+      "filename": "threading-and-memory64.1.wasm",
+      "module_type": "binary",
+      "text": "type must match previous context type"
+    }
+  ]
+}

tests/snapshots/cli/component-model/memory64/context.wast.json

@@ -8,43 +8,57 @@
       "module_type": "binary"
     },
     {
-      "type": "module",
-      "line": 22,
+      "type": "assert_invalid",
+      "line": 23,
       "filename": "context.1.wasm",
-      "module_type": "binary"
+      "module_type": "binary",
+      "text": "type must match previous context type"
     },
     {
       "type": "assert_invalid",
-      "line": 31,
+      "line": 29,
       "filename": "context.2.wasm",
       "module_type": "binary",
-      "text": "found:    (func (result i64))"
+      "text": "type must match previous context type"
     },
     {
-      "type": "assert_invalid",
-      "line": 39,
+      "type": "module",
+      "line": 36,
       "filename": "context.3.wasm",
-      "module_type": "binary",
-      "text": "found:    (func (param i64))"
+      "module_type": "binary"
     },
     {
       "type": "assert_invalid",
       "line": 47,
       "filename": "context.4.wasm",
       "module_type": "binary",
-      "text": "found:    (func (result i32))"
+      "text": "found:    (func (result i64))"
     },
     {
       "type": "assert_invalid",
       "line": 55,
       "filename": "context.5.wasm",
       "module_type": "binary",
-      "text": "found:    (func (param i32))"
+      "text": "found:    (func (param i64))"
     },
     {
-      "type": "module",
+      "type": "assert_invalid",
       "line": 63,
       "filename": "context.6.wasm",
+      "module_type": "binary",
+      "text": "found:    (func (result i32))"
+    },
+    {
+      "type": "assert_invalid",
+      "line": 71,
+      "filename": "context.7.wasm",
+      "module_type": "binary",
+      "text": "found:    (func (param i32))"
+    },
+    {
+      "type": "module",
+      "line": 79,
+      "filename": "context.8.wasm",
       "module_type": "binary"
     }
   ]

tests/snapshots/cli/component-model/memory64/context.wast/3.print

@@ -0,0 +1,8 @@
+(component
+  (component (;0;)
+    (core func (;0;) (canon context.set i64 0))
+  )
+  (component (;1;)
+    (core func (;0;) (canon context.get i32 0))
+  )
+)