spirv-fuzz: Handle more types when extending OpPhi instructions (#3969)
Fixes #3953.
diff --git a/source/fuzz/fuzzer_pass_add_dead_breaks.cpp b/source/fuzz/fuzzer_pass_add_dead_breaks.cpp
index 5873a07..e726c63 100644
--- a/source/fuzz/fuzzer_pass_add_dead_breaks.cpp
+++ b/source/fuzz/fuzzer_pass_add_dead_breaks.cpp
@@ -67,11 +67,15 @@
// anything.
if (!block.IsSuccessor(merge_block)) {
merge_block->ForEachPhiInst([this, &phi_ids](opt::Instruction* phi) {
- // Add an additional operand for OpPhi instruction.
- //
- // We mark the constant as irrelevant so that we can replace it with
- // a more interesting value later.
- phi_ids.push_back(FindOrCreateZeroConstant(phi->type_id(), true));
+ // Add an additional operand for OpPhi instruction. Use a constant
+ // if possible, and an undef otherwise.
+ if (fuzzerutil::CanCreateConstant(GetIRContext(), phi->type_id())) {
+ // We mark the constant as irrelevant so that we can replace it
+ // with a more interesting value later.
+ phi_ids.push_back(FindOrCreateZeroConstant(phi->type_id(), true));
+ } else {
+ phi_ids.push_back(FindOrCreateGlobalUndef(phi->type_id()));
+ }
});
}
diff --git a/source/fuzz/fuzzer_pass_add_dead_continues.cpp b/source/fuzz/fuzzer_pass_add_dead_continues.cpp
index ed7233f..24617ae 100644
--- a/source/fuzz/fuzzer_pass_add_dead_continues.cpp
+++ b/source/fuzz/fuzzer_pass_add_dead_continues.cpp
@@ -58,11 +58,15 @@
// If this is the case, we don't need to do anything.
if (!block.IsSuccessor(continue_block)) {
continue_block->ForEachPhiInst([this, &phi_ids](opt::Instruction* phi) {
- // Add an additional operand for OpPhi instruction.
- //
- // We mark the constant as irrelevant so that we can replace it with a
- // more interesting value later.
- phi_ids.push_back(FindOrCreateZeroConstant(phi->type_id(), true));
+ // Add an additional operand for OpPhi instruction. Use a constant
+ // if possible, and an undef otherwise.
+ if (fuzzerutil::CanCreateConstant(GetIRContext(), phi->type_id())) {
+ // We mark the constant as irrelevant so that we can replace it with
+ // a more interesting value later.
+ phi_ids.push_back(FindOrCreateZeroConstant(phi->type_id(), true));
+ } else {
+ phi_ids.push_back(FindOrCreateGlobalUndef(phi->type_id()));
+ }
});
}
