diff --git a/kokoro/windows/build.bat b/kokoro/windows/build.bat
index 623bf1f1ac..a5b62243c6 100644
--- a/kokoro/windows/build.bat
+++ b/kokoro/windows/build.bat
@@ -119,7 +119,7 @@ cmake --build . --config %BUILD_TYPE% || goto :error
 
 call :status "Running tint_unittests"
 @echo on
-%BUILD_TYPE%\tint_unittests.exe --validate-hlsl || goto :error
+%BUILD_TYPE%\tint_unittests.exe || goto :error
 @echo off
 
 call :status "Testing test/test-all.sh"
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index fde494d9ef..4847c78f06 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -892,7 +892,6 @@ if(${TINT_BUILD_TESTS})
       writer/msl/generator_impl_type_test.cc
       writer/msl/generator_impl_unary_op_test.cc
       writer/msl/generator_impl_variable_decl_statement_test.cc
-      writer/msl/test_helper.cc
       writer/msl/test_helper.h
     )
   endif()
@@ -930,7 +929,6 @@ if(${TINT_BUILD_TESTS})
       writer/hlsl/generator_impl_unary_op_test.cc
       writer/hlsl/generator_impl_variable_decl_statement_test.cc
       writer/hlsl/generator_impl_workgroup_var_test.cc
-      writer/hlsl/test_helper.cc
       writer/hlsl/test_helper.h
     )
   endif()
@@ -947,7 +945,7 @@ if(${TINT_BUILD_TESTS})
   ## Test executable
   target_include_directories(
       tint_unittests PRIVATE ${gmock_SOURCE_DIR}/include)
-  target_link_libraries(tint_unittests libtint gmock tint_val)
+  target_link_libraries(tint_unittests libtint gmock tint_utils_io)
   tint_default_compile_options(tint_unittests)
 
   if(${TINT_BUILD_SPV_READER} OR ${TINT_BUILD_SPV_WRITER})
diff --git a/src/test_main.cc b/src/test_main.cc
index cd1ea39722..c01a825036 100644
--- a/src/test_main.cc
+++ b/src/test_main.cc
@@ -14,7 +14,6 @@
 
 #include "gmock/gmock.h"
 #include "src/reader/spirv/parser_impl_test_helper.h"
-#include "src/utils/io/command.h"
 #include "src/writer/hlsl/test_helper.h"
 #include "src/writer/msl/test_helper.h"
 
@@ -25,10 +24,6 @@ void TintInternalCompilerErrorReporter(const tint::diag::List& diagnostics) {
 }
 
 struct Flags {
-  bool validate_hlsl = false;
-  std::string dxc_path;
-  bool validate_msl = false;
-  std::string xcrun_path;
   bool spirv_reader_dump_converted = false;
 
   bool parse(int argc, char** argv) {
@@ -36,26 +31,7 @@ struct Flags {
     for (int i = 1; i < argc && !errored; i++) {
       auto match = [&](std::string name) { return name == argv[i]; };
 
-      auto parse_value = [&](std::string name, std::string& value) {
-        if (!match(name)) {
-          return false;
-        }
-        if (i + 1 >= argc) {
-          std::cout << "Expected value for flag " << name << "" << std::endl;
-          errored = true;
-          return false;
-        }
-        i++;
-        value = argv[i];
-        return true;
-      };
-
-      if (match("--validate-hlsl") || parse_value("--dxc-path", dxc_path)) {
-        validate_hlsl = true;
-      } else if (match("--validate-msl") ||
-                 parse_value("--xcrun-path", xcrun_path)) {
-        validate_msl = true;
-      } else if (match("--dump-spirv")) {
+      if (match("--dump-spirv")) {
         spirv_reader_dump_converted = true;
       } else {
         std::cout << "Unknown flag '" << argv[i] << "'" << std::endl;
@@ -77,59 +53,6 @@ int main(int argc, char** argv) {
     return -1;
   }
 
-#if TINT_BUILD_HLSL_WRITER
-  // This must be kept alive for the duration of RUN_ALL_TESTS() as the c_str()
-  // is passed into tint::writer::hlsl::EnableHLSLValidation(), which does not
-  // make a copy. This is to work around Chromium's strict rules on globals
-  // having no constructors / destructors.
-  std::string dxc_path;
-  if (flags.validate_hlsl) {
-    auto dxc = flags.dxc_path.empty() ? tint::utils::Command::LookPath("dxc")
-                                      : tint::utils::Command(flags.dxc_path);
-
-    if (!dxc.Found()) {
-      std::cout << "DXC executable not found" << std::endl;
-      return -1;
-    }
-
-    std::cout << "HLSL validation with DXC enabled" << std::endl;
-
-    dxc_path = dxc.Path();
-    tint::writer::hlsl::EnableHLSLValidation(dxc_path.c_str());
-  } else {
-    std::cout << "HLSL validation with DXC is not enabled" << std::endl;
-  }
-#endif  // TINT_BUILD_HLSL_WRITER
-
-#if TINT_BUILD_MSL_WRITER
-#ifdef TINT_ENABLE_MSL_VALIDATION_USING_METAL_API
-  std::cout << "MSL validation with metal API enabled" << std::endl;
-#else
-  // This must be kept alive for the duration of RUN_ALL_TESTS() as the c_str()
-  // is passed into tint::writer::msl::EnableMSLValidation(), which does not
-  // make a copy. This is to work around Chromium's strict rules on globals
-  // having no constructors / destructors.
-  std::string xcrun_path;
-  if (flags.validate_msl) {
-    auto xcrun = flags.xcrun_path.empty()
-                     ? tint::utils::Command::LookPath("xcrun")
-                     : tint::utils::Command(flags.xcrun_path);
-
-    if (!xcrun.Found()) {
-      std::cout << "xcrun executable not found" << std::endl;
-      return -1;
-    }
-
-    std::cout << "MSL validation with XCode SDK enabled" << std::endl;
-
-    xcrun_path = xcrun.Path();
-    tint::writer::msl::EnableMSLValidation(xcrun_path.c_str());
-  } else {
-    std::cout << "MSL validation with XCode SDK is not enabled" << std::endl;
-  }
-#endif  // TINT_ENABLE_MSL_VALIDATION_USING_METAL_API
-#endif  // TINT_BUILD_MSL_WRITER
-
 #if TINT_BUILD_SPV_READER
   if (flags.spirv_reader_dump_converted) {
     tint::reader::spirv::test::DumpSuccessfullyConvertedSpirv();
diff --git a/src/writer/hlsl/generator_impl_constructor_test.cc b/src/writer/hlsl/generator_impl_constructor_test.cc
index 3564389e1c..9d1822619b 100644
--- a/src/writer/hlsl/generator_impl_constructor_test.cc
+++ b/src/writer/hlsl/generator_impl_constructor_test.cc
@@ -31,8 +31,6 @@ TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Bool) {
 
   ASSERT_TRUE(gen.Generate(out)) << gen.error();
   EXPECT_THAT(result(), HasSubstr("false"));
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Int) {
@@ -42,8 +40,6 @@ TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Int) {
 
   ASSERT_TRUE(gen.Generate(out)) << gen.error();
   EXPECT_THAT(result(), HasSubstr("-12345"));
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_UInt) {
@@ -53,8 +49,6 @@ TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_UInt) {
 
   ASSERT_TRUE(gen.Generate(out)) << gen.error();
   EXPECT_THAT(result(), HasSubstr("56779u"));
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Float) {
@@ -65,8 +59,6 @@ TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Float) {
 
   ASSERT_TRUE(gen.Generate(out)) << gen.error();
   EXPECT_THAT(result(), HasSubstr("1073741824.0f"));
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Type_Float) {
@@ -76,8 +68,6 @@ TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Type_Float) {
 
   ASSERT_TRUE(gen.Generate(out)) << gen.error();
   EXPECT_THAT(result(), HasSubstr("float(-0.000012f)"));
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Type_Bool) {
@@ -87,8 +77,6 @@ TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Type_Bool) {
 
   ASSERT_TRUE(gen.Generate(out)) << gen.error();
   EXPECT_THAT(result(), HasSubstr("bool(true)"));
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Type_Int) {
@@ -98,8 +86,6 @@ TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Type_Int) {
 
   ASSERT_TRUE(gen.Generate(out)) << gen.error();
   EXPECT_THAT(result(), HasSubstr("int(-12345)"));
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Type_Uint) {
@@ -109,8 +95,6 @@ TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Type_Uint) {
 
   ASSERT_TRUE(gen.Generate(out)) << gen.error();
   EXPECT_THAT(result(), HasSubstr("uint(12345u)"));
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Type_Vec) {
@@ -120,8 +104,6 @@ TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Type_Vec) {
 
   ASSERT_TRUE(gen.Generate(out)) << gen.error();
   EXPECT_THAT(result(), HasSubstr("float3(1.0f, 2.0f, 3.0f)"));
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Type_Vec_Empty) {
@@ -131,8 +113,6 @@ TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Type_Vec_Empty) {
 
   ASSERT_TRUE(gen.Generate(out)) << gen.error();
   EXPECT_THAT(result(), HasSubstr("float3(0.0f, 0.0f, 0.0f)"));
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Constructor,
@@ -143,8 +123,6 @@ TEST_F(HlslGeneratorImplTest_Constructor,
 
   ASSERT_TRUE(gen.Generate(out)) << gen.error();
   EXPECT_THAT(result(), HasSubstr("float3((2.0f).xxx)"));
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Constructor,
@@ -155,8 +133,6 @@ TEST_F(HlslGeneratorImplTest_Constructor,
 
   ASSERT_TRUE(gen.Generate(out)) << gen.error();
   EXPECT_THAT(result(), HasSubstr("bool3((true).xxx)"));
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Constructor,
@@ -167,8 +143,6 @@ TEST_F(HlslGeneratorImplTest_Constructor,
 
   ASSERT_TRUE(gen.Generate(out)) << gen.error();
   EXPECT_THAT(result(), HasSubstr("int3((2).xxx)"));
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Constructor,
@@ -179,8 +153,6 @@ TEST_F(HlslGeneratorImplTest_Constructor,
 
   ASSERT_TRUE(gen.Generate(out)) << gen.error();
   EXPECT_THAT(result(), HasSubstr("uint3((2u).xxx)"));
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Type_Mat) {
@@ -195,8 +167,6 @@ TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Type_Mat) {
       result(),
       HasSubstr(
           "float2x3(float3(1.0f, 2.0f, 3.0f), float3(3.0f, 4.0f, 5.0f))"));
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Type_Mat_Empty) {
@@ -208,8 +178,6 @@ TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Type_Mat_Empty) {
 
   EXPECT_THAT(result(),
               HasSubstr("float2x3(0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f)"));
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Type_Array) {
@@ -223,8 +191,6 @@ TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Type_Array) {
   EXPECT_THAT(result(),
               HasSubstr("{float3(1.0f, 2.0f, 3.0f), float3(4.0f, 5.0f, 6.0f),"
                         " float3(7.0f, 8.0f, 9.0f)}"));
-
-  Validate();
 }
 
 // TODO(bclayton): Zero-init arrays
@@ -238,8 +204,6 @@ TEST_F(HlslGeneratorImplTest_Constructor,
   EXPECT_THAT(result(),
               HasSubstr("{float3(0.0f, 0.0f, 0.0f), float3(0.0f, 0.0f, 0.0f),"
                         " float3(0.0f, 0.0f, 0.0f)}"));
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Type_Struct) {
@@ -255,8 +219,6 @@ TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Type_Struct) {
 
   ASSERT_TRUE(gen.Generate(out)) << gen.error();
   EXPECT_THAT(result(), HasSubstr("{1, 2.0f, int3(3, 4, 5)}"));
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Type_Struct_Empty) {
@@ -272,8 +234,6 @@ TEST_F(HlslGeneratorImplTest_Constructor, EmitConstructor_Type_Struct_Empty) {
 
   ASSERT_TRUE(gen.Generate(out)) << gen.error();
   EXPECT_THAT(result(), HasSubstr("{0, 0.0f, int3(0, 0, 0)}"));
-
-  Validate();
 }
 
 }  // namespace
diff --git a/src/writer/hlsl/generator_impl_function_test.cc b/src/writer/hlsl/generator_impl_function_test.cc
index 7c9f54e628..e7f467fe99 100644
--- a/src/writer/hlsl/generator_impl_function_test.cc
+++ b/src/writer/hlsl/generator_impl_function_test.cc
@@ -96,8 +96,6 @@ TEST_F(HlslGeneratorImplTest_Function,
 }
 
 )");
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Function, PtrParameter) {
@@ -115,8 +113,6 @@ TEST_F(HlslGeneratorImplTest_Function, PtrParameter) {
 }
 
 )"));
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Function,
@@ -145,8 +141,6 @@ tint_symbol_2 frag_main(tint_symbol_1 tint_symbol) {
 }
 
 )");
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Function,
@@ -178,8 +172,6 @@ tint_symbol_2 frag_main(tint_symbol_1 tint_symbol) {
 }
 
 )");
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Function,
@@ -252,8 +244,6 @@ void frag_main(tint_symbol_3 tint_symbol_2) {
 }
 
 )");
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Function,
@@ -320,8 +310,6 @@ tint_symbol_2 vert_main2() {
 }
 
 )");
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Function,
@@ -374,8 +362,6 @@ void frag_main() {
 }
 
 )");
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Function,
@@ -416,8 +402,6 @@ void frag_main() {
 }
 
 )");
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Function,
@@ -461,8 +445,6 @@ void frag_main() {
 }
 
 )");
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Function,
@@ -505,8 +487,6 @@ void frag_main() {
 }
 
 )");
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Function,
@@ -546,8 +526,6 @@ void frag_main() {
 }
 
 )");
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Function,
@@ -588,8 +566,6 @@ void frag_main() {
 }
 
 )");
-
-  Validate();
 }
 
 // TODO(crbug.com/tint/697): Remove this test
@@ -652,8 +628,6 @@ ep_1_out ep_1(ep_1_in tint_in) {
 }
 
 )");
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Function,
@@ -695,8 +669,6 @@ ep_1_out ep_1() {
 }
 
 )");
-
-  Validate();
 }
 
 // TODO(crbug.com/tint/697): Remove this test
@@ -751,8 +723,6 @@ ep_1_out ep_1(ep_1_in tint_in) {
 }
 
 )");
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Function,
@@ -801,8 +771,6 @@ void frag_main() {
 }
 
 )");
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Function,
@@ -850,8 +818,6 @@ void frag_main() {
 }
 
 )");
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Function,
@@ -891,8 +857,6 @@ ep_1_out ep_1() {
 }
 
 )");
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Function,
@@ -930,8 +894,6 @@ void main() {
 }
 
 )");
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Function,
@@ -951,8 +913,6 @@ void main() {
 }
 
 )");
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Function,
@@ -978,8 +938,6 @@ void main() {
 }
 
 )");
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Function,
@@ -1014,8 +972,6 @@ void main() {
 }
 
 )");
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Function, Emit_Function_WithArrayParams) {
@@ -1112,8 +1068,6 @@ void b() {
 }
 
 )");
-
-  Validate();
 }
 
 }  // namespace
diff --git a/src/writer/hlsl/generator_impl_intrinsic_test.cc b/src/writer/hlsl/generator_impl_intrinsic_test.cc
index 6c5290c7d7..bec3c2fc86 100644
--- a/src/writer/hlsl/generator_impl_intrinsic_test.cc
+++ b/src/writer/hlsl/generator_impl_intrinsic_test.cc
@@ -504,8 +504,6 @@ void main() {
 }
 
 )");
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Intrinsic, WorkgroupBarrier) {
@@ -523,8 +521,6 @@ void main() {
 }
 
 )");
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_Intrinsic, Ignore) {
@@ -549,8 +545,6 @@ void main() {
 }
 
 )");
-
-  Validate();
 }
 
 }  // namespace
diff --git a/src/writer/hlsl/generator_impl_intrinsic_texture_test.cc b/src/writer/hlsl/generator_impl_intrinsic_texture_test.cc
index 7e50eacf0f..0bb8c00b1c 100644
--- a/src/writer/hlsl/generator_impl_intrinsic_texture_test.cc
+++ b/src/writer/hlsl/generator_impl_intrinsic_texture_test.cc
@@ -375,8 +375,6 @@ TEST_P(HlslGeneratorIntrinsicTextureTest, Call) {
 
   EXPECT_THAT(result(), HasSubstr(expected.pre));
   EXPECT_THAT(result(), HasSubstr(expected.out));
-
-  Validate();
 }
 
 INSTANTIATE_TEST_SUITE_P(
diff --git a/src/writer/hlsl/generator_impl_member_accessor_test.cc b/src/writer/hlsl/generator_impl_member_accessor_test.cc
index bfcfca71cb..8605f24918 100644
--- a/src/writer/hlsl/generator_impl_member_accessor_test.cc
+++ b/src/writer/hlsl/generator_impl_member_accessor_test.cc
@@ -184,8 +184,6 @@ TEST_P(HlslGeneratorImplTest_MemberAccessor_StorageBufferLoad, Test) {
 
   ASSERT_TRUE(gen.Generate(out)) << gen.error();
   EXPECT_THAT(result(), HasSubstr(p.expected));
-
-  Validate();
 }
 
 INSTANTIATE_TEST_SUITE_P(
@@ -259,8 +257,6 @@ TEST_P(HlslGeneratorImplTest_MemberAccessor_StorageBufferStore, Test) {
 
   ASSERT_TRUE(gen.Generate(out)) << gen.error();
   EXPECT_THAT(result(), HasSubstr(p.expected));
-
-  Validate();
 }
 
 INSTANTIATE_TEST_SUITE_P(
@@ -361,8 +357,6 @@ void main() {
 
 )";
   EXPECT_EQ(result(), expected);
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_MemberAccessor,
@@ -399,8 +393,6 @@ void main() {
 
 )";
   EXPECT_EQ(result(), expected);
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_MemberAccessor,
@@ -545,8 +537,6 @@ void main() {
 
 )";
   EXPECT_EQ(result(), expected);
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_MemberAccessor,
@@ -593,8 +583,6 @@ void main() {
 
 )";
   EXPECT_EQ(result(), expected);
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_MemberAccessor,
@@ -641,8 +629,6 @@ void main() {
 
 )";
   EXPECT_EQ(result(), expected);
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_MemberAccessor,
@@ -689,8 +675,6 @@ void main() {
 
 )";
   EXPECT_EQ(result(), expected);
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_MemberAccessor, StorageBuffer_Store_MultiLevel) {
@@ -733,8 +717,6 @@ void main() {
 
 )";
   EXPECT_EQ(result(), expected);
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_MemberAccessor,
@@ -781,8 +763,6 @@ void main() {
 
 )";
   EXPECT_EQ(result(), expected);
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_MemberAccessor, Swizzle_xyz) {
@@ -794,8 +774,6 @@ TEST_F(HlslGeneratorImplTest_MemberAccessor, Swizzle_xyz) {
   GeneratorImpl& gen = SanitizeAndBuild();
   ASSERT_TRUE(gen.Generate(out)) << gen.error();
   EXPECT_THAT(result(), HasSubstr("my_vec.xyz"));
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_MemberAccessor, Swizzle_gbr) {
@@ -807,8 +785,6 @@ TEST_F(HlslGeneratorImplTest_MemberAccessor, Swizzle_gbr) {
   GeneratorImpl& gen = SanitizeAndBuild();
   ASSERT_TRUE(gen.Generate(out)) << gen.error();
   EXPECT_THAT(result(), HasSubstr("my_vec.gbr"));
-
-  Validate();
 }
 
 }  // namespace
diff --git a/src/writer/hlsl/generator_impl_type_test.cc b/src/writer/hlsl/generator_impl_type_test.cc
index 3add6d98f3..a5301d6bc0 100644
--- a/src/writer/hlsl/generator_impl_type_test.cc
+++ b/src/writer/hlsl/generator_impl_type_test.cc
@@ -367,8 +367,6 @@ TEST_P(HlslDepthTexturesTest, Emit) {
 
   ASSERT_TRUE(gen.Generate(out)) << gen.error();
   EXPECT_THAT(result(), HasSubstr(params.result));
-
-  Validate();
 }
 INSTANTIATE_TEST_SUITE_P(
     HlslGeneratorImplTest_Type,
@@ -425,8 +423,6 @@ TEST_P(HlslSampledTexturesTest, Emit) {
 
   ASSERT_TRUE(gen.Generate(out)) << gen.error();
   EXPECT_THAT(result(), HasSubstr(params.result));
-
-  Validate();
 }
 INSTANTIATE_TEST_SUITE_P(
     HlslGeneratorImplTest_Type,
@@ -567,8 +563,6 @@ TEST_P(HlslStorageTexturesTest, Emit) {
 
   ASSERT_TRUE(gen.Generate(out)) << gen.error();
   EXPECT_THAT(result(), HasSubstr(params.result));
-
-  Validate();
 }
 INSTANTIATE_TEST_SUITE_P(
     HlslGeneratorImplTest_Type,
diff --git a/src/writer/hlsl/generator_impl_workgroup_var_test.cc b/src/writer/hlsl/generator_impl_workgroup_var_test.cc
index 19ab36f31e..a965be76f2 100644
--- a/src/writer/hlsl/generator_impl_workgroup_var_test.cc
+++ b/src/writer/hlsl/generator_impl_workgroup_var_test.cc
@@ -34,8 +34,6 @@ TEST_F(HlslGeneratorImplTest_WorkgroupVar, Basic) {
 
   ASSERT_TRUE(gen.Generate(out)) << gen.error();
   EXPECT_THAT(result(), HasSubstr("groupshared float wg;\n"));
-
-  Validate();
 }
 
 TEST_F(HlslGeneratorImplTest_WorkgroupVar, Aliased) {
@@ -49,8 +47,6 @@ TEST_F(HlslGeneratorImplTest_WorkgroupVar, Aliased) {
 
   ASSERT_TRUE(gen.Generate(out)) << gen.error();
   EXPECT_THAT(result(), HasSubstr("groupshared float wg;\n"));
-
-  Validate();
 }
 
 }  // namespace
diff --git a/src/writer/hlsl/test_helper.cc b/src/writer/hlsl/test_helper.cc
deleted file mode 100644
index acadabd759..0000000000
--- a/src/writer/hlsl/test_helper.cc
+++ /dev/null
@@ -1,45 +0,0 @@
-// Copyright 2021 The Tint Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-#include "src/writer/hlsl/test_helper.h"
-
-namespace tint {
-namespace writer {
-namespace hlsl {
-
-namespace {
-
-const char* dxc_path = nullptr;
-
-}  // namespace
-
-void EnableHLSLValidation(const char* dxc) {
-  dxc_path = dxc;
-}
-
-val::Result Validate(Program* program, GeneratorImpl* generator) {
-  if (!dxc_path) {
-    return val::Result{};
-  }
-
-  std::ostringstream hlsl;
-  if (!generator->Generate(hlsl)) {
-    return {true, generator->error(), ""};
-  }
-  return val::Hlsl(dxc_path, hlsl.str(), program);
-}
-
-}  // namespace hlsl
-}  // namespace writer
-}  // namespace tint
diff --git a/src/writer/hlsl/test_helper.h b/src/writer/hlsl/test_helper.h
index 8a71505d53..6ccbb3ba39 100644
--- a/src/writer/hlsl/test_helper.h
+++ b/src/writer/hlsl/test_helper.h
@@ -23,24 +23,12 @@
 #include "src/transform/hlsl.h"
 #include "src/transform/manager.h"
 #include "src/transform/renamer.h"
-#include "src/val/val.h"
 #include "src/writer/hlsl/generator_impl.h"
 
 namespace tint {
 namespace writer {
 namespace hlsl {
 
-/// EnableHLSLValidation enables verification of HLSL shaders by running DXC and
-/// checking no errors are reported.
-/// @param dxc_path the path to the DXC executable
-void EnableHLSLValidation(const char* dxc_path);
-
-/// Validate attempts to compile the shader with DXC if found on PATH.
-/// @param program the HLSL program
-/// @param generator the HLSL generator
-/// @return the result of the compile
-val::Result Validate(Program* program, GeneratorImpl* generator);
-
 /// Helper class for testing
 template <typename BODY>
 class TestHelperBase : public BODY, public ProgramBuilder {
@@ -106,19 +94,6 @@ class TestHelperBase : public BODY, public ProgramBuilder {
     return *gen_;
   }
 
-  /// Validate passes the generated HLSL from the generator to the DXC compiler
-  /// on `PATH` for checking the program can be compiled.
-  /// If DXC finds problems the test will fail.
-  /// If DXC is not on `PATH` then Validate() does nothing.
-  void Validate() const {
-    auto res = hlsl::Validate(program.get(), gen_.get());
-    if (res.failed) {
-      FAIL() << "HLSL Validation failed.\n\n"
-             << res.source << "\n\n"
-             << res.output;
-    }
-  }
-
   /// @returns the result string
   std::string result() const { return out.str(); }
 
diff --git a/src/writer/msl/generator_impl_function_test.cc b/src/writer/msl/generator_impl_function_test.cc
index a331b4eb58..abf8f1e186 100644
--- a/src/writer/msl/generator_impl_function_test.cc
+++ b/src/writer/msl/generator_impl_function_test.cc
@@ -118,8 +118,6 @@ fragment tint_symbol_2 frag_main(tint_symbol_1 tint_symbol [[stage_in]]) {
 }
 
 )");
-
-  Validate();
 }
 
 TEST_F(MslGeneratorImplTest, Emit_Decoration_EntryPoint_WithInOut_Builtins) {
@@ -149,8 +147,6 @@ fragment tint_symbol_1 frag_main(float4 coord [[position]]) {
 }
 
 )");
-
-  Validate();
 }
 
 TEST_F(MslGeneratorImplTest,
@@ -224,8 +220,6 @@ fragment void frag_main(float4 tint_symbol_3 [[position]], tint_symbol_4 tint_sy
 }
 
 )");
-
-  Validate();
 }
 
 TEST_F(MslGeneratorImplTest,
@@ -293,8 +287,6 @@ vertex tint_symbol_2 vert_main2() {
 }
 
 )");
-
-  Validate();
 }
 
 TEST_F(MslGeneratorImplTest,
diff --git a/src/writer/msl/generator_impl_intrinsic_test.cc b/src/writer/msl/generator_impl_intrinsic_test.cc
index 0e6c09fc96..0d69beaff2 100644
--- a/src/writer/msl/generator_impl_intrinsic_test.cc
+++ b/src/writer/msl/generator_impl_intrinsic_test.cc
@@ -365,8 +365,6 @@ kernel void func() {
 }
 
 )");
-
-  Validate();
 }
 
 }  // namespace
diff --git a/src/writer/msl/test_helper.cc b/src/writer/msl/test_helper.cc
deleted file mode 100644
index b129c8a562..0000000000
--- a/src/writer/msl/test_helper.cc
+++ /dev/null
@@ -1,56 +0,0 @@
-// Copyright 2021 The Tint Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-#include "src/writer/msl/test_helper.h"
-
-#include "src/utils/io/command.h"
-#include "src/utils/io/tmpfile.h"
-
-namespace tint {
-namespace writer {
-namespace msl {
-
-namespace {
-
-const char* xcrun_path = nullptr;
-
-}  // namespace
-
-void EnableMSLValidation(const char* xcrun) {
-  xcrun_path = xcrun;
-}
-
-val::Result Validate(Program* program) {
-#ifdef TINT_ENABLE_MSL_VALIDATION_USING_METAL_API
-  auto gen = std::make_unique<GeneratorImpl>(program);
-  if (!gen->Generate()) {
-    return {true, gen->error(), ""};
-  }
-  return tint::val::MslUsingMetalAPI(gen->result());
-#else   // TINT_ENABLE_MSL_VALIDATION_USING_METAL_API
-  if (!xcrun_path) {
-    return val::Result{};
-  }
-
-  auto gen = std::make_unique<GeneratorImpl>(program);
-  if (!gen->Generate()) {
-    return {true, gen->error(), ""};
-  }
-  return val::Msl(xcrun_path, gen->result());
-#endif  // TINT_ENABLE_MSL_VALIDATION_USING_METAL_API
-}
-
-}  // namespace msl
-}  // namespace writer
-}  // namespace tint
diff --git a/src/writer/msl/test_helper.h b/src/writer/msl/test_helper.h
index af75a21f07..3ae78c731d 100644
--- a/src/writer/msl/test_helper.h
+++ b/src/writer/msl/test_helper.h
@@ -22,23 +22,12 @@
 #include "gtest/gtest.h"
 #include "src/program_builder.h"
 #include "src/transform/msl.h"
-#include "src/val/val.h"
 #include "src/writer/msl/generator_impl.h"
 
 namespace tint {
 namespace writer {
 namespace msl {
 
-/// Enables verification of MSL shaders by running the Metal compiler and
-/// checking no errors are reported.
-/// @param xcrun_path the path to the `xcrun` executable
-void EnableMSLValidation(const char* xcrun_path);
-
-/// Validate attempts to compile the shader with DXC if found on PATH.
-/// @param program the MSL program
-/// @return the result of the compile
-val::Result Validate(Program* program);
-
 /// Helper class for testing
 template <typename BASE>
 class TestHelperBase : public BASE, public ProgramBuilder {
@@ -96,22 +85,6 @@ class TestHelperBase : public BASE, public ProgramBuilder {
     return *gen_;
   }
 
-  /// Validate generates MSL code for the current contents of `program` and
-  /// passes the output of the generator to the XCode SDK Metal compiler.
-  ///
-  /// If the Metal compiler finds problems, then any GTest test case that
-  /// invokes this function test will fail.
-  /// This function does nothing, if the Metal compiler path has not been
-  /// configured by calling `EnableMSLValidation()`.
-  void Validate() {
-    auto res = msl::Validate(program.get());
-    if (res.failed) {
-      FAIL() << "MSL Validation failed.\n\n"
-             << res.source << "\n\n"
-             << res.output;
-    }
-  }
-
   /// The program built with a call to Build()
   std::unique_ptr<Program> program;
 
diff --git a/test/BUILD.gn b/test/BUILD.gn
index 32c390ce2f..014c1d69d9 100644
--- a/test/BUILD.gn
+++ b/test/BUILD.gn
@@ -94,7 +94,6 @@ source_set("tint_unittests_main") {
       ":tint_unittests_msl_writer_src",
       ":tint_unittests_spv_reader_src",
       "${tint_root_dir}/src:libtint",
-      "${tint_root_dir}/src:tint_val",
     ]
   }
 }
@@ -135,7 +134,7 @@ template("tint_unittests_source_set") {
     deps += [
       ":gmock_and_gtest",
       "${tint_root_dir}/src:libtint",
-      "${tint_root_dir}/src:tint_val",
+      "${tint_root_dir}/src:tint_utils_io",
     ]
   }
 }
@@ -549,7 +548,6 @@ tint_unittests_source_set("tint_unittests_msl_writer_src") {
     "../src/writer/msl/generator_impl_type_test.cc",
     "../src/writer/msl/generator_impl_unary_op_test.cc",
     "../src/writer/msl/generator_impl_variable_decl_statement_test.cc",
-    "../src/writer/msl/test_helper.cc",
     "../src/writer/msl/test_helper.h",
   ]
 
@@ -592,7 +590,6 @@ tint_unittests_source_set("tint_unittests_hlsl_writer_src") {
     "../src/writer/hlsl/generator_impl_unary_op_test.cc",
     "../src/writer/hlsl/generator_impl_variable_decl_statement_test.cc",
     "../src/writer/hlsl/generator_impl_workgroup_var_test.cc",
-    "../src/writer/hlsl/test_helper.cc",
     "../src/writer/hlsl/test_helper.h",
   ]