Reject folding comparisons with unfoldable types. (#3370)
Reject folding comparisons with unfoldable types.
Fixes #3343
When CCP is evaluating an instruction, it was trying to fold a
comparison with 64 bit integers. This was causing a fold failure later
since the folder still cannot deal with 64 bit integers.
diff --git a/source/opt/instruction.cpp b/source/opt/instruction.cpp
index 19f6fff..126848e 100644
--- a/source/opt/instruction.cpp
+++ b/source/opt/instruction.cpp
@@ -623,7 +623,19 @@
return false;
}
Instruction* type = context()->get_def_use_mgr()->GetDef(type_id());
- return folder.IsFoldableType(type);
+ if (!folder.IsFoldableType(type)) {
+ return false;
+ }
+
+ // Even if the type of the instruction is foldable, its operands may not be
+ // foldable (e.g., comparisons of 64bit types). Check that all operand types
+ // are foldable before accepting the instruction.
+ return WhileEachInOperand([&folder, this](const uint32_t* op_id) {
+ Instruction* def_inst = context()->get_def_use_mgr()->GetDef(*op_id);
+ Instruction* def_inst_type =
+ context()->get_def_use_mgr()->GetDef(def_inst->type_id());
+ return folder.IsFoldableType(def_inst_type);
+ });
}
bool Instruction::IsFloatingPointFoldingAllowed() const {
diff --git a/test/opt/fold_test.cpp b/test/opt/fold_test.cpp
index db01924..beb26f2 100644
--- a/test/opt/fold_test.cpp
+++ b/test/opt/fold_test.cpp
@@ -3297,7 +3297,16 @@
"%2 = OpIMul %int %3 %int_1\n" +
"OpReturn\n" +
"OpFunctionEnd",
- 2, 3)
+ 2, 3),
+ // Test case 42: Don't fold comparisons of 64-bit types
+ // (https://github.com/KhronosGroup/SPIRV-Tools/issues/3343).
+ InstructionFoldingCase<uint32_t>(
+ Header() + "%main = OpFunction %void None %void_func\n" +
+ "%main_lab = OpLabel\n" +
+ "%2 = OpSLessThan %bool %long_0 %long_2\n" +
+ "OpReturn\n" +
+ "OpFunctionEnd",
+ 2, 0)
));
INSTANTIATE_TEST_SUITE_P(CompositeExtractFoldingTest, GeneralInstructionFoldingTest,
