spirv-fuzz: Do not replace the Sample argument in OpImageTexelPointer (#3311)
The Sample argument of OpImageTexelPointer is sometimes required to be
a zero constant. It thus cannot be replaced with a synonym in
general. This change avoids replacing this argument with a synonym.
diff --git a/source/fuzz/transformation_replace_id_with_synonym.cpp b/source/fuzz/transformation_replace_id_with_synonym.cpp
index 3a10682..e427f3c 100644
--- a/source/fuzz/transformation_replace_id_with_synonym.cpp
+++ b/source/fuzz/transformation_replace_id_with_synonym.cpp
@@ -170,6 +170,15 @@
return false;
}
}
+
+ if (use_instruction->opcode() == SpvOpImageTexelPointer &&
+ use_in_operand_index == 2) {
+ // The OpImageTexelPointer instruction has a Sample parameter that in some
+ // situations must be an id for the value 0. To guard against disrupting
+ // that requirement, we do not replace this argument to that instruction.
+ return false;
+ }
+
return true;
}
diff --git a/test/fuzz/transformation_replace_id_with_synonym_test.cpp b/test/fuzz/transformation_replace_id_with_synonym_test.cpp
index 6b514a3..37e9510 100644
--- a/test/fuzz/transformation_replace_id_with_synonym_test.cpp
+++ b/test/fuzz/transformation_replace_id_with_synonym_test.cpp
@@ -1393,6 +1393,63 @@
ASSERT_TRUE(IsEqual(env, after_transformation, context.get()));
}
+TEST(TransformationReplaceIdWithSynonymTest,
+ DoNotReplaceSampleParameterOfOpImageTexelPointer) {
+ const std::string shader = R"(
+ OpCapability Shader
+ %1 = OpExtInstImport "GLSL.std.450"
+ OpMemoryModel Logical GLSL450
+ OpEntryPoint Fragment %2 "main" %3
+ OpExecutionMode %2 OriginUpperLeft
+ OpSource ESSL 310
+ %4 = OpTypeVoid
+ %5 = OpTypeFunction %4
+ %6 = OpTypeInt 32 1
+ %7 = OpTypePointer Function %6
+ %8 = OpConstant %6 2
+ %9 = OpConstant %6 0
+ %10 = OpConstant %6 10
+ %11 = OpTypeBool
+ %12 = OpConstant %6 1
+ %13 = OpTypeFloat 32
+ %14 = OpTypePointer Image %13
+ %15 = OpTypeImage %13 2D 0 0 0 0 Rgba8
+ %16 = OpTypePointer Private %15
+ %3 = OpVariable %16 Private
+ %17 = OpTypeVector %6 2
+ %18 = OpConstantComposite %17 %9 %9
+ %2 = OpFunction %4 None %5
+ %19 = OpLabel
+ %100 = OpCopyObject %6 %9
+ %20 = OpImageTexelPointer %14 %3 %18 %9
+ OpReturn
+ OpFunctionEnd
+ )";
+
+ const auto env = SPV_ENV_UNIVERSAL_1_5;
+ const auto consumer = nullptr;
+ const auto context = BuildModule(env, consumer, shader, kFuzzAssembleOption);
+ ASSERT_TRUE(IsValid(env, context.get()));
+
+ FactManager fact_manager;
+ spvtools::ValidatorOptions validator_options;
+ TransformationContext transformation_context(&fact_manager,
+ validator_options);
+
+ // Add synonym fact relating %100 and %9.
+ transformation_context.GetFactManager()->AddFact(MakeSynonymFact(100, 9),
+ context.get());
+
+ // Not legal the Sample argument of OpImageTexelPointer needs to be a zero
+ // constant.
+ ASSERT_FALSE(
+ TransformationReplaceIdWithSynonym(
+ MakeIdUseDescriptor(
+ 9, MakeInstructionDescriptor(20, SpvOpImageTexelPointer, 0), 2),
+ 100)
+ .IsApplicable(context.get(), transformation_context));
+}
+
} // namespace
} // namespace fuzz
} // namespace spvtools
