Add a type propagation phase after building SSA.
This ensures all phis have a type.
Change-Id: I7e4f9a16d1efb5f64c493c1351749b352c870cbd
diff --git a/compiler/optimizing/ssa_builder.cc b/compiler/optimizing/ssa_builder.cc
index 54c3c5d..471307e 100644
--- a/compiler/optimizing/ssa_builder.cc
+++ b/compiler/optimizing/ssa_builder.cc
@@ -15,22 +15,12 @@
*/
#include "ssa_builder.h"
+
#include "nodes.h"
+#include "ssa_type_propagation.h"
namespace art {
-static Primitive::Type MergeTypes(Primitive::Type existing, Primitive::Type new_type) {
- // We trust the verifier has already done the necessary checking.
- switch (existing) {
- case Primitive::kPrimFloat:
- case Primitive::kPrimDouble:
- case Primitive::kPrimNot:
- return existing;
- default:
- return new_type;
- }
-}
-
void SsaBuilder::BuildSsa() {
// 1) Visit in reverse post order. We need to have all predecessors of a block visited
// (with the exception of loops) in order to create the right environment for that
@@ -44,18 +34,18 @@
HBasicBlock* block = loop_headers_.Get(i);
for (HInstructionIterator it(block->GetPhis()); !it.Done(); it.Advance()) {
HPhi* phi = it.Current()->AsPhi();
- Primitive::Type type = Primitive::kPrimVoid;
for (size_t pred = 0; pred < block->GetPredecessors().Size(); pred++) {
HInstruction* input = ValueOfLocal(block->GetPredecessors().Get(pred), phi->GetRegNumber());
phi->AddInput(input);
- type = MergeTypes(type, input->GetType());
}
- phi->SetType(type);
}
}
- // TODO: Now that the type of loop phis is set, we need a type propagation phase.
- // 3) Clear locals.
+ // 3) Propagate types of phis.
+ SsaTypePropagation type_propagation(GetGraph());
+ type_propagation.Run();
+
+ // 4) Clear locals.
// TODO: Move this to a dead code eliminator phase.
for (HInstructionIterator it(GetGraph()->GetEntryBlock()->GetInstructions());
!it.Done();
@@ -118,16 +108,10 @@
if (is_different) {
HPhi* phi = new (GetGraph()->GetArena()) HPhi(
GetGraph()->GetArena(), local, block->GetPredecessors().Size(), Primitive::kPrimVoid);
- Primitive::Type type = Primitive::kPrimVoid;
for (size_t i = 0; i < block->GetPredecessors().Size(); i++) {
HInstruction* value = ValueOfLocal(block->GetPredecessors().Get(i), local);
- // We need to merge the incoming types, as the Dex format does not
- // guarantee the inputs have the same type. In particular the 0 constant is
- // used for all types, but the graph builder treats it as an int.
- type = MergeTypes(type, value->GetType());
phi->SetRawInputAt(i, value);
}
- phi->SetType(type);
block->AddPhi(phi);
value = phi;
}