[spirv-reader] Add problematic CFG case as disabled test
In this case, a basic block is a continue target
for both an outer loop and is also for itself as a
single-block loop.
Bug: Tint:3
Change-Id: If361004a4b871966674ca972922c45e712ce7c9c
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/22420
Reviewed-by: dan sinclair <dsinclair@google.com>
diff --git a/src/reader/spirv/function_cfg_test.cc b/src/reader/spirv/function_cfg_test.cc
index 0e29f5f..7f4b81e 100644
--- a/src/reader/spirv/function_cfg_test.cc
+++ b/src/reader/spirv/function_cfg_test.cc
@@ -6702,6 +6702,33 @@
)";
}
+TEST_F(SpvParserTest, DISABLED_BlockIsContinueForMoreThanOneHeader) {
+ // This is valid SPIR-V for Vulkan, but breaks my assumption that a block
+ // could only be a continue target for at most one header. Block 50
+ // is a single block loop but also the continue target for the outer loop.
+ auto assembly = CommonTypes() + R"(
+ %100 = OpFunction %void None %voidfn
+
+ %10 = OpLabel
+ OpBranch %20
+
+ %20 = OpLabel ; outer loop
+ OpLoopMerge %99 %50 None
+ OpBranchConditional %cond %50 %99
+
+ %50 = OpLabel ; continue target, but also single-block loop
+ OpLoopMerge %80 %50 None
+ OpBranchConditional %cond2 %50 %80
+
+ %80 = OpLabel
+ OpBranch %20 ; backedge for outer loop
+
+ %99 = OpLabel
+ OpReturn
+ OpFunctionEnd
+)";
+}
+
} // namespace
} // namespace spirv
} // namespace reader
