A64: Implement support for stack slots in gap resolver

src/a64/lithium-gap-resolver-a64.cc

Index: src/a64/lithium-gap-resolver-a64.cc
diff --git a/src/a64/lithium-gap-resolver-a64.cc b/src/a64/lithium-gap-resolver-a64.cc
index 6a29ac142c32958dc2e4cfe019167df4032aee7e..1a4b0e5fd8adc5ef894858ffb7a52225d68cecda 100644
--- a/src/a64/lithium-gap-resolver-a64.cc
+++ b/src/a64/lithium-gap-resolver-a64.cc
@@ -184,7 +184,7 @@ void LGapResolver::BreakCycle(int index) {
   if (source->IsRegister()) {
     __ Mov(kSavedValue, cgen_->ToRegister(source));
   } else if (source->IsStackSlot()) {
-    UNIMPLEMENTED();
+    __ Ldr(kSavedValue, cgen_->ToMemOperand(source));
   } else if (source->IsDoubleRegister()) {
     // TODO(all): We should use a double register to store the value to avoid
     // the penalty of the mov across register banks. We are going to reserve
@@ -194,7 +194,7 @@ void LGapResolver::BreakCycle(int index) {
     // do that.
     __ Fmov(kSavedValue, cgen_->ToDoubleRegister(source));
   } else if (source->IsDoubleStackSlot()) {
-    UNIMPLEMENTED();
+    __ Ldr(kSavedValue, cgen_->ToMemOperand(source));
   } else {
     UNREACHABLE();
   }
@@ -213,11 +213,11 @@ void LGapResolver::RestoreValue() {
   if (saved_destination_->IsRegister()) {
     __ Mov(cgen_->ToRegister(saved_destination_), kSavedValue);
   } else if (saved_destination_->IsStackSlot()) {
-    UNIMPLEMENTED();
+    __ Str(kSavedValue, cgen_->ToMemOperand(saved_destination_));
   } else if (saved_destination_->IsDoubleRegister()) {
     __ Fmov(cgen_->ToDoubleRegister(saved_destination_), kSavedValue);
   } else if (saved_destination_->IsDoubleStackSlot()) {
-    UNIMPLEMENTED();
+    __ Str(kSavedValue, cgen_->ToMemOperand(saved_destination_));
   } else {
     UNREACHABLE();
   }
@@ -294,8 +294,10 @@ void LGapResolver::EmitMove(int index) {
     if (destination->IsDoubleRegister()) {
       __ Ldr(cgen_->ToDoubleRegister(destination), src);
     } else {
-      // TODO(all): double stack slot to double stack slot move.
-      UNIMPLEMENTED();
+      ASSERT(destination->IsDoubleStackSlot());

[Rodolph Perfetta (ARM), 2014/02/04 16:32:10]

How about reusing EmitStackSlotMove define below

+      DoubleRegister temp = crankshaft_fp_scratch;
+      __ Ldr(temp, src);
+      __ Str(temp, cgen_->ToMemOperand(destination));
     }
 
   } else {