Remove tint's usage of Validator

Also update comments and arch design to remove references to the
Validator.

Bug: tint:642
Change-Id: Ic0b4779ae4712a393ff209014daf25e23f32be6d
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/47061
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>
Reviewed-by: James Price <jrprice@google.com>
Commit-Queue: Antonio Maiorano <amaiorano@google.com>

docs/arch.md

@@ -36,9 +36,9 @@
       ┃       ┃  ┗━━━━━┛ ┗━━━━━━━┛ ┗━━━━━━━━━━┛ ┗━━━━━━━━━┛  ┃
       ┃       ┗━━━━━━━━━━━━━━━━━━━━━━━┳━━━━━━━━━━━━━━━━━━━━━━┛
       ▲                               ▼
-┏━━━━━┻━━━━━┓                   ┏━━━━━┻━━━━━┓       ┏━━━━━━━━━━━┓
-┃ Transform ┃◄━━━━━━━━━━━━━━━━━◄┃ Validator ┣━━━━━━►┃ Inspector ┃
-┗━━━━━━━━━━━┛                   ┗━━━━━┳━━━━━┛       ┗━━━━━━━━━━━┛
+┏━━━━━┻━━━━━┓                         ┃             ┏━━━━━━━━━━━┓
+┃ Transform ┃◄━━━━━━━━━━━━━━━━━━━━━━━━╋━━━━━━━━━━━━►┃ Inspector ┃
+┗━━━━━━━━━━━┛                         ┃             ┗━━━━━━━━━━━┛
                                       ▼
 ┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┻━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓
 ┃                                  Writer                                  ┃
@@ -148,11 +148,8 @@ The `Resolver` will automatically run when a `Program` is built.
 A `Resolver` creates the `Program`s semantic information by analyzing the
 `Program`s AST and type information.
 
-The `Resolver` will do the minimal amount of validation required in order
-to always be accessing valid nodes, reporting any errors found in the
-`Program`'s diagnostics. Even if the `Resolver` doesn't generate any
-errors doesn't mean the generated `Program` is semantically valid. Use the
-`Validator` to check for a `Program`'s final validity.
+The `Resolver` will validate to make sure the generated `Program` is
+semantically valid.
 
 ## Program
 
@@ -161,21 +158,13 @@ A `Program` holds an immutable version of the information from the
 `Resolver`.
 
 Like `ProgramBuilder`, `Program::IsValid()` may be called to ensure the AST is
-structurally correct and that the `Resolver` did not report any errors.
-`Program::IsValid()` does not perform semantic validation, use the `Validator`
-to check for a `Program`'s final validity.
+structurally correct and semantically valid, and that the `Resolver` did not
+report any errors.
 
 Unlike the `ProgramBuilder`, a `Program` is fully immutable, and is part of the
 public Tint API. The immutable nature of `Program`s make these entirely safe
 to share between multiple threads without the use of synchronization primitives.
 
-## Validation
-
-The `Validator` checks a `Program` for static validity as specified by the WGSL
-language, and reports any validation errors found. Attempting to pass a
-`Program` that does not pass validation on to later stages will result in
-undefined behavior.
-
 ## Inspector
 
 The inspectors job is to go through the `Program` and pull out various pieces of

fuzzers/tint_common_fuzzer.cc

@@ -84,11 +84,6 @@ int CommonFuzzer::Run(const uint8_t* data, size_t size) {
     return 0;
   }
 
-  Validator v;
-  if (!v.Validate(&program)) {
-    return 0;
-  }
-
   if (inspector_enabled_) {
     inspector::Inspector inspector(&program);
 

samples/main.cc

@@ -671,12 +671,6 @@ int main(int argc, const char** argv) {
     return 1;
   }
 
-  tint::Validator v;
-  if (!v.Validate(program.get())) {
-    diag_formatter.format(v.diagnostics(), diag_printer.get());
-    return 1;
-  }
-
   tint::transform::Manager transform_manager;
   for (const auto& name : options.transforms) {
     // TODO(dsinclair): The vertex pulling transform requires setup code to

src/inspector/inspector.cc

@@ -262,8 +262,8 @@ std::map<uint32_t, Scalar> Inspector::GetConstantIDs() {
     }
 
     // If there are conflicting defintions for a constant id, that is invalid
-    // WGSL, so the validator should catch it. Thus here the inspector just
-    // assumes all definitians of the constant id are the same, so only needs
+    // WGSL, so the resolver should catch it. Thus here the inspector just
+    // assumes all definitions of the constant id are the same, so only needs
     // to find the first reference to constant id.
     uint32_t constant_id = var->constant_id();
     if (result.find(constant_id) != result.end()) {

src/resolver/decoration_validation_test.cc

@@ -256,7 +256,7 @@ TEST_P(VariableDecorationTest, IsValid) {
   }
 }
 INSTANTIATE_TEST_SUITE_P(
-    ValidatorTest,
+    ResolverDecorationValidationTest,
     VariableDecorationTest,
     testing::Values(TestParams{DecorationKind::kAccess, false},
                     TestParams{DecorationKind::kAlign, false},
@@ -290,7 +290,7 @@ TEST_P(FunctionDecorationTest, IsValid) {
   }
 }
 INSTANTIATE_TEST_SUITE_P(
-    ValidatorTest,
+    ResolverDecorationValidationTest,
     FunctionDecorationTest,
     testing::Values(TestParams{DecorationKind::kAccess, false},
                     TestParams{DecorationKind::kAlign, false},

src/resolver/resolver.cc

@@ -1252,8 +1252,7 @@ bool Resolver::MemberAccessor(ast::MemberAccessorExpression* expr) {
       }
     } else {
       // The vector will have a number of components equal to the length of
-      // the swizzle. This assumes the validator will check that the swizzle
-      // is correct.
+      // the swizzle.
       ret = builder_->create<type::Vector>(vec->type(),
                                            static_cast<uint32_t>(size));
     }