spirv-reader: fix emission of INT_MIN literal

Fixed: tint:1818
Change-Id: Ieb19f874d248a3a1c11c96f5ae06c4db14e0c811
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/118540
Auto-Submit: David Neto <dneto@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: David Neto <dneto@google.com>
Reviewed-by: James Price <jrprice@google.com>

src/tint/BUILD.gn

@@ -1656,6 +1656,7 @@ if (tint_build_unittests) {
       "reader/spirv/function_var_test.cc",
       "reader/spirv/namer_test.cc",
       "reader/spirv/parser_impl_barrier_test.cc",
+      "reader/spirv/parser_impl_constant_test.cc",
       "reader/spirv/parser_impl_convert_member_decoration_test.cc",
       "reader/spirv/parser_impl_convert_type_test.cc",
       "reader/spirv/parser_impl_function_decl_test.cc",

src/tint/CMakeLists.txt

@@ -1065,6 +1065,7 @@ if(TINT_BUILD_TESTS)
       reader/spirv/function_var_test.cc
       reader/spirv/namer_test.cc
       reader/spirv/parser_impl_barrier_test.cc
+      reader/spirv/parser_impl_constant_test.cc
       reader/spirv/parser_impl_convert_member_decoration_test.cc
       reader/spirv/parser_impl_convert_type_test.cc
       reader/spirv/parser_impl_function_decl_test.cc

src/tint/reader/spirv/parser_impl.cc

@@ -1953,11 +1953,20 @@ TypedExpression ParserImpl::MakeConstantExpressionForScalarSpirvConstant(
     // See https://bugs.chromium.org/p/tint/issues/detail?id=34
     return Switch(
         ast_type,
-        [&](const I32*) {
+        [&](const I32*) -> TypedExpression {
-            return TypedExpression{ty_.I32(),
+            const auto value = spirv_const->GetS32();
+            if (value == std::numeric_limits<int32_t>::min()) {
+                // Avoid overflowing i-suffixed literal.
+                return {ty_.I32(),
+                        builder_.Construct(
+                            source, builder_.ty.i32(),
                             create<ast::IntLiteralExpression>(
-                                       source, static_cast<int64_t>(spirv_const->GetS32()),
+                                source, value, ast::IntLiteralExpression::Suffix::kNone))};
+            } else {
+                return {ty_.I32(),
+                        create<ast::IntLiteralExpression>(source, static_cast<int64_t>(value),
                                                           ast::IntLiteralExpression::Suffix::kI)};
+            }
         },
         [&](const U32*) {
             return TypedExpression{ty_.U32(),

src/tint/reader/spirv/parser_impl_constant_test.cc

@@ -0,0 +1,142 @@
+// Copyright 2020 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 "gmock/gmock.h"
+#include "src/tint/reader/spirv/parser_impl_test_helper.h"
+#include "src/tint/reader/spirv/spirv_tools_helpers_test.h"
+
+namespace tint::reader::spirv {
+namespace {
+
+using ::testing::Eq;
+using ::testing::HasSubstr;
+
+std::string Preamble() {
+    return R"(
+    OpCapability Shader
+    OpCapability Sampled1D
+    OpCapability Image1D
+    OpCapability StorageImageExtendedFormats
+    OpCapability ImageQuery
+    OpMemoryModel Logical Simple
+  )";
+}
+
+std::string FragMain() {
+    return R"(
+    OpEntryPoint Fragment %main "main" ; assume no IO
+    OpExecutionMode %main OriginUpperLeft
+  )";
+}
+
+std::string MainBody() {
+    return R"(
+    %main = OpFunction %void None %voidfn
+    %main_entry = OpLabel
+    OpReturn
+    OpFunctionEnd
+  )";
+}
+
+std::string CommonTypes() {
+    return R"(
+    %void = OpTypeVoid
+    %voidfn = OpTypeFunction %void
+
+    %bool = OpTypeBool
+    %float = OpTypeFloat 32
+    %uint = OpTypeInt 32 0
+    %int = OpTypeInt 32 1
+
+    %v2int = OpTypeVector %int 2
+    %v3int = OpTypeVector %int 3
+    %v4int = OpTypeVector %int 4
+    %v2uint = OpTypeVector %uint 2
+    %v3uint = OpTypeVector %uint 3
+    %v4uint = OpTypeVector %uint 4
+    %v2float = OpTypeVector %float 2
+    %v3float = OpTypeVector %float 3
+    %v4float = OpTypeVector %float 4
+
+    %true = OpConstantTrue %bool
+    %false = OpConstantFalse %bool
+
+    %int_1 = OpConstant %int 1
+    %int_m5 = OpConstant %int -5
+    %int_min = OpConstant %int 0x80000000
+    %int_max = OpConstant %int 0x7fffffff
+    %uint_0 = OpConstant %uint 0
+    %uint_max = OpConstant %uint 0xffffffff
+
+    %float_minus_5 = OpConstant %float -5
+    %float_half = OpConstant %float 0.5
+    %float_ten = OpConstant %float 10
+  )";
+}
+
+struct ConstantCase {
+    std::string spirv_type;
+    std::string spirv_value;
+    std::string wgsl_value;
+};
+inline std::ostream& operator<<(std::ostream& out, const ConstantCase& c) {
+    out << "ConstantCase(" << c.spirv_type << ", " << c.spirv_value << ", " << c.wgsl_value << ")";
+    return out;
+}
+
+using SpvParserConstantTest = SpvParserTestBase<::testing::TestWithParam<ConstantCase>>;
+
+TEST_P(SpvParserConstantTest, ReturnValue) {
+    const auto spirv_type = GetParam().spirv_type;
+    const auto spirv_value = GetParam().spirv_value;
+    const auto wgsl_value = GetParam().wgsl_value;
+    const auto assembly = Preamble() + FragMain() + CommonTypes() + R"(
+     %fty = OpTypeFunction )" +
+                          spirv_type + R"(
+
+     %200 = OpFunction )" +
+                          spirv_type + R"( None %fty
+     %fentry = OpLabel
+     OpReturnValue )" + spirv_value +
+                          R"(
+     OpFunctionEnd
+     )" + MainBody();
+    auto p = parser(test::Assemble(assembly));
+    ASSERT_TRUE(p->Parse());
+    auto fe = p->function_emitter(200);
+    EXPECT_TRUE(fe.EmitBody()) << p->error();
+    EXPECT_TRUE(p->error().empty());
+    const auto got = test::ToString(p->program(), fe.ast_body());
+    const auto expect = std::string("return ") + wgsl_value + std::string(";\n");
+
+    EXPECT_EQ(got, expect);
+}
+
+INSTANTIATE_TEST_SUITE_P(Scalars,
+                         SpvParserConstantTest,
+                         ::testing::ValuesIn(std::vector<ConstantCase>{
+                             {"%bool", "%true", "true"},
+                             {"%bool", "%false", "false"},
+                             {"%int", "%int_1", "1i"},
+                             {"%int", "%int_m5", "-5i"},
+                             {"%int", "%int_min", "i32(-2147483648)"},
+                             {"%int", "%int_max", "2147483647i"},
+                             {"%uint", "%uint_0", "0u"},
+                             {"%uint", "%uint_max", "4294967295u"},
+                             {"%float", "%float_minus_5", "-5.0f"},
+                             {"%float", "%float_half", "0.5f"},
+                             {"%float", "%float_ten", "10.0f"}}));
+
+}  // namespace
+}  // namespace tint::reader::spirv