ARM64: Avoid regeneration of constants.

src/arm64/lithium-arm64.cc

Index: src/arm64/lithium-arm64.cc
diff --git a/src/arm64/lithium-arm64.cc b/src/arm64/lithium-arm64.cc
index 02127066536aa8dead082292d77f04a50b4f21de..6f60e8ae0d7b7f436a7800155d59326fd9b81b32 100644
--- a/src/arm64/lithium-arm64.cc
+++ b/src/arm64/lithium-arm64.cc
@@ -375,7 +375,12 @@ LUnallocated* LChunkBuilder::ToUnallocated(DoubleRegister reg) {
 LOperand* LChunkBuilder::Use(HValue* value, LUnallocated* operand) {
   if (value->EmitAtUses()) {
     HInstruction* instr = HInstruction::cast(value);
-    VisitInstruction(instr);
+    if (value->IsConstant() && IsCachedConstant(HConstant::cast(value),
+                                                current_block_)) {
+      // We will reuse the cached value.
+    } else {
+      VisitInstruction(instr);
+    }
   }
   operand->set_virtual_register(value->id());
   return operand;
@@ -586,7 +591,13 @@ void LChunkBuilder::DoBasicBlock(HBasicBlock* block) {
   ASSERT(is_building());
   current_block_ = block;
 
+  if (graph()->has_osr() &&
+      (block == graph()->osr()->osr_entry())) {
+    constant_cache_.Clear();
+  }
+
   if (block->IsStartBlock()) {
+    constant_cache_.Clear();
     block->UpdateEnvironment(graph_->start_environment());
     argument_count_ = 0;
   } else if (block->predecessors()->length() == 1) {
@@ -1328,6 +1339,7 @@ LInstruction* LChunkBuilder::DoCompareMap(HCompareMap* instr) {
 
 
 LInstruction* LChunkBuilder::DoConstant(HConstant* instr) {
+  CacheConstant(instr, current_block_);
   Representation r = instr->representation();
   if (r.IsSmi()) {
     return DefineAsRegister(new(zone()) LConstantS);