spirv-reader: add test for bad continue-block from single-block loop
Prove this error is caught by SPIR-V validation.
This requires a recent version of SPIRV-Tools.
Fixed: tint:793
Change-Id: I30977de7c4d1c291ab9ea13df80189426a842521
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/51040
Auto-Submit: David Neto <dneto@google.com>
Commit-Queue: Alan Baker <alanbaker@google.com>
Reviewed-by: Alan Baker <alanbaker@google.com>
diff --git a/src/reader/spirv/function_cfg_test.cc b/src/reader/spirv/function_cfg_test.cc
index ca042cf..044e7ae 100644
--- a/src/reader/spirv/function_cfg_test.cc
+++ b/src/reader/spirv/function_cfg_test.cc
@@ -14759,6 +14759,52 @@
ASSERT_EQ(expect, got) << got;
}
+TEST_F(SpvParserCFGTest,
+ EmitBody_ContinueFromSingleBlockLoopToOuterLoop_IsError) {
+ // crbug.com/tint/793
+ // This is invalid SPIR-V but the validator was only recently upgraded
+ // to catch it.
+ auto assembly = CommonTypes() + R"(
+ %100 = OpFunction %void None %voidfn
+ %5 = OpLabel
+ OpBranch %10
+
+ %10 = OpLabel ; outer loop header
+ OpLoopMerge %99 %89 None
+ OpBranchConditional %cond %99 %20
+
+ %20 = OpLabel ; inner loop single block loop
+ OpLoopMerge %79 %20 None
+
+ ; true -> continue to outer loop
+ ; false -> self-loop
+ ; The true branch is invalid because a "continue block", i.e. the block
+ ; containing the branch to the continue target, "is valid only for the
+ ; innermost loop it is nested inside of".
+ ; So it can't branch to the continue target of an outer loop.
+ OpBranchConditional %cond %89 %20
+
+ %79 = OpLabel ; merge for outer loop
+ OpUnreachable
+
+ %89 = OpLabel
+ OpBranch %10 ; backedge for outer loop
+
+ %99 = OpLabel ; merge for outer
+ OpReturn
+
+ OpFunctionEnd
+
+)";
+ auto p = parser(test::Assemble(assembly));
+ EXPECT_FALSE(p->Parse());
+ EXPECT_FALSE(p->success());
+ EXPECT_THAT(p->error(),
+ HasSubstr("block <ID> 20[%20] exits the continue headed by <ID> "
+ "20[%20], but not via a structured exit"))
+ << p->error();
+}
+
} // namespace
} // namespace spirv
} // namespace reader
