[spirv-writer] Generate load in Unary Op generation.

When generating a unary operation we need to make sure we correctly
generate the load otherwise the resulting SPIR-V will be invalid. This
CL adds the required GenerateLoadIfNeeded call into the unary
generation.

Bug: tint292
Change-Id: Ia04314726afdda8f63a78e8e52f996681373db6e
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/31620
Commit-Queue: dan sinclair <dsinclair@chromium.org>
Commit-Queue: David Neto <dneto@google.com>
Reviewed-by: David Neto <dneto@google.com>

src/writer/spirv/builder.cc

@@ -1072,6 +1072,7 @@ uint32_t Builder::GenerateUnaryOpExpression(ast::UnaryOpExpression* expr) {
   if (val_id == 0) {
     return 0;
   }
+  val_id = GenerateLoadIfNeeded(expr->expr()->result_type(), val_id);
 
   auto type_id = GenerateTypeIfNeeded(expr->result_type());
   if (type_id == 0) {

src/writer/spirv/builder_binary_expression_test.cc

@@ -124,6 +124,44 @@ TEST_P(BinaryArithSignedIntegerTest, Vector) {
   EXPECT_EQ(DumpInstructions(b.functions()[0].instructions()),
             "%5 = " + param.name + " %1 %4 %4\n");
 }
+TEST_P(BinaryArithSignedIntegerTest, Scalar_Loads) {
+  auto param = GetParam();
+
+  ast::type::I32Type i32;
+
+  ast::Variable var("param", ast::StorageClass::kFunction, &i32);
+
+  auto lhs = std::make_unique<ast::IdentifierExpression>("param");
+  auto rhs = std::make_unique<ast::IdentifierExpression>("param");
+
+  ast::BinaryExpression expr(param.op, std::move(lhs), std::move(rhs));
+
+  Context ctx;
+  ast::Module mod;
+  TypeDeterminer td(&ctx, &mod);
+  td.RegisterVariableForTesting(&var);
+  EXPECT_TRUE(td.DetermineResultType(&expr)) << td.error();
+
+  Builder b(&mod);
+  b.push_function(Function{});
+  EXPECT_TRUE(b.GenerateFunctionVariable(&var)) << b.error();
+  EXPECT_EQ(b.GenerateBinaryExpression(&expr), 7u) << b.error();
+  ASSERT_FALSE(b.has_error()) << b.error();
+
+  EXPECT_EQ(DumpInstructions(b.types()), R"(%3 = OpTypeInt 32 1
+%2 = OpTypePointer Function %3
+%4 = OpConstantNull %3
+)");
+  EXPECT_EQ(DumpInstructions(b.functions()[0].variables()),
+            R"(%1 = OpVariable %2 Function %4
+)");
+  EXPECT_EQ(DumpInstructions(b.functions()[0].instructions()),
+            R"(%5 = OpLoad %3 %1
+%6 = OpLoad %3 %1
+%7 = )" + param.name +
+                R"( %3 %5 %6
+)");
+}
 INSTANTIATE_TEST_SUITE_P(
     BuilderTest,
     BinaryArithSignedIntegerTest,

src/writer/spirv/builder_unary_op_expression_test.cc

@@ -23,6 +23,7 @@
 #include "src/ast/type/bool_type.h"
 #include "src/ast/type/f32_type.h"
 #include "src/ast/type/i32_type.h"
+#include "src/ast/type/vector_type.h"
 #include "src/ast/unary_op_expression.h"
 #include "src/context.h"
 #include "src/type_determiner.h"
@@ -111,6 +112,42 @@ TEST_F(BuilderTest, UnaryOp_Not) {
 )");
 }
 
+TEST_F(BuilderTest, UnaryOp_LoadRequired) {
+  ast::type::F32Type f32;
+  ast::type::VectorType vec(&f32, 3);
+
+  ast::Variable var("param", ast::StorageClass::kFunction, &vec);
+
+  ast::UnaryOpExpression expr(
+      ast::UnaryOp::kNegation,
+      std::make_unique<ast::IdentifierExpression>("param"));
+
+  Context ctx;
+  ast::Module mod;
+  TypeDeterminer td(&ctx, &mod);
+  td.RegisterVariableForTesting(&var);
+  EXPECT_TRUE(td.DetermineResultType(&expr)) << td.error();
+
+  Builder b(&mod);
+  b.push_function(Function{});
+  EXPECT_TRUE(b.GenerateFunctionVariable(&var)) << b.error();
+  EXPECT_EQ(b.GenerateUnaryOpExpression(&expr), 6u) << b.error();
+  ASSERT_FALSE(b.has_error()) << b.error();
+
+  EXPECT_EQ(DumpInstructions(b.types()), R"(%4 = OpTypeFloat 32
+%3 = OpTypeVector %4 3
+%2 = OpTypePointer Function %3
+%5 = OpConstantNull %3
+)");
+  EXPECT_EQ(DumpInstructions(b.functions()[0].variables()),
+            R"(%1 = OpVariable %2 Function %5
+)");
+  EXPECT_EQ(DumpInstructions(b.functions()[0].instructions()),
+            R"(%7 = OpLoad %3 %1
+%6 = OpFNegate %3 %7
+)");
+}
+
 }  // namespace
 }  // namespace spirv
 }  // namespace writer