Update dominates to check for null nodes (#3271)
* Update dominates to check for null nodes
Fixes #3270
diff --git a/source/opt/dominator_tree.cpp b/source/opt/dominator_tree.cpp
index c9346e1..da5073a 100644
--- a/source/opt/dominator_tree.cpp
+++ b/source/opt/dominator_tree.cpp
@@ -241,6 +241,7 @@
bool DominatorTree::Dominates(const DominatorTreeNode* a,
const DominatorTreeNode* b) const {
+ if (!a || !b) return false;
// Node A dominates node B if they are the same.
if (a == b) return true;
diff --git a/test/opt/loop_optimizations/loop_descriptions.cpp b/test/opt/loop_optimizations/loop_descriptions.cpp
index 91dbdc6..4d2f989 100644
--- a/test/opt/loop_optimizations/loop_descriptions.cpp
+++ b/test/opt/loop_optimizations/loop_descriptions.cpp
@@ -379,6 +379,43 @@
EXPECT_EQ(loop.GetLatchBlock()->id(), 30u);
}
+TEST_F(PassClassTest, UnreachableMerge) {
+ const std::string text = R"(
+ OpCapability Shader
+ OpMemoryModel Logical GLSL450
+ OpEntryPoint Fragment %1 "main"
+ OpExecutionMode %1 OriginUpperLeft
+ %void = OpTypeVoid
+ %3 = OpTypeFunction %void
+ %1 = OpFunction %void None %3
+ %4 = OpLabel
+ OpBranch %5
+ %5 = OpLabel
+ OpLoopMerge %6 %7 None
+ OpBranch %8
+ %8 = OpLabel
+ OpBranch %9
+ %9 = OpLabel
+ OpBranch %7
+ %7 = OpLabel
+ OpBranch %5
+ %6 = OpLabel
+ OpUnreachable
+ OpFunctionEnd
+)";
+
+ std::unique_ptr<IRContext> context =
+ BuildModule(SPV_ENV_UNIVERSAL_1_3, nullptr, text,
+ SPV_TEXT_TO_BINARY_OPTION_PRESERVE_NUMERIC_IDS);
+ Module* module = context->module();
+ EXPECT_NE(nullptr, module) << "Assembling failed for shader:\n"
+ << text << std::endl;
+ const Function* f = spvtest::GetFunction(module, 1);
+ LoopDescriptor ld{context.get(), f};
+
+ EXPECT_EQ(ld.NumLoops(), 1u);
+}
+
} // namespace
} // namespace opt
} // namespace spvtools
