From a561c7cacbb178f3a3fc6c985ef0dbb85298ee94 Mon Sep 17 00:00:00 2001
From: Dzmitry Malyshau <kvarkus@gmail.com>
Date: Mon, 14 Sep 2020 14:25:03 -0400
Subject: [PATCH] validator: try resolving the types

---
 src/proc/typifier.rs  |  1 +
 src/proc/validator.rs | 31 +++++++++++++++++++++++++++++--
 2 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/src/proc/typifier.rs b/src/proc/typifier.rs
index c3f10ee773..787c8adacf 100644
--- a/src/proc/typifier.rs
+++ b/src/proc/typifier.rs
@@ -37,6 +37,7 @@ impl Clone for Resolution {
     }
 }
 
+#[derive(Debug)]
 pub struct Typifier {
     resolutions: Vec<Resolution>,
 }
diff --git a/src/proc/validator.rs b/src/proc/validator.rs
index 364d7fd101..7d26f14417 100644
--- a/src/proc/validator.rs
+++ b/src/proc/validator.rs
@@ -1,7 +1,12 @@
+use super::typifier::{ResolveContext, ResolveError, Typifier};
 use crate::arena::Handle;
 
 #[derive(Debug)]
-pub struct Validator {}
+pub struct Validator {
+    //Note: this is a bit tricky: some of the front-ends as well as backends
+    // already have to use the typifier, so the work here is redundant in a way.
+    typifier: Typifier,
+}
 
 #[derive(Clone, Debug, thiserror::Error)]
 pub enum ValidationError {
@@ -9,6 +14,8 @@ pub enum ValidationError {
     InvalidTypeWidth(crate::ScalarKind, crate::Bytes),
     #[error("The type handle can not be resolved")]
     UnresolvedType(Handle<crate::Type>),
+    #[error("Expression type can't be resolved")]
+    Resolve(Handle<crate::Function>, ResolveError),
     #[error("There are instructions after `return`/`break`/`continue`")]
     InvalidControlFlowExitTail,
 }
@@ -16,11 +23,14 @@ pub enum ValidationError {
 impl Validator {
     /// Construct a new validator instance.
     pub fn new() -> Self {
-        Validator {}
+        Validator {
+            typifier: Typifier::new(),
+        }
     }
 
     /// Check the given module to be valid.
     pub fn validate(&mut self, module: &crate::Module) -> Result<(), ValidationError> {
+        // check the types
         for (handle, ty) in module.types.iter() {
             use crate::TypeInner as Ti;
             match ty.inner {
@@ -58,6 +68,23 @@ impl Validator {
             }
         }
 
+        // check the type resolution of expressions
+        for (fun_handle, fun) in module.functions.iter() {
+            let resolve_ctx = ResolveContext {
+                constants: &module.constants,
+                global_vars: &module.global_variables,
+                local_vars: &fun.local_variables,
+                functions: &module.functions,
+                parameter_types: &fun.parameter_types,
+            };
+            if let Err(e) = self
+                .typifier
+                .resolve_all(&fun.expressions, &module.types, &resolve_ctx)
+            {
+                return Err(ValidationError::Resolve(fun_handle, e));
+            }
+        }
+
         Ok(())
     }
 }