Turbofan: Modify WASM linkage to store floats using only 4 bytes.

src/compiler/arm/code-generator-arm.cc

Index: src/compiler/arm/code-generator-arm.cc
diff --git a/src/compiler/arm/code-generator-arm.cc b/src/compiler/arm/code-generator-arm.cc
index cef16c2faa09ad8085c9110d7e34aae5a7000a8d..66b3b8e6cd9a5894cf48081db621fdd84f8fcb37 100644
--- a/src/compiler/arm/code-generator-arm.cc
+++ b/src/compiler/arm/code-generator-arm.cc
@@ -1204,8 +1204,15 @@ CodeGenerator::CodeGenResult CodeGenerator::AssembleArchInstruction(
     }
     case kArmPush:
       if (instr->InputAt(0)->IsFPRegister()) {
-        __ vpush(i.InputDoubleRegister(0));
-        frame_access_state()->IncreaseSPDelta(kDoubleSize / kPointerSize);
+        LocationOperand* op = LocationOperand::cast(instr->InputAt(0));
+        if (op->representation() == MachineRepresentation::kFloat64) {
+          __ vpush(i.InputFloat64Register(0));
+          frame_access_state()->IncreaseSPDelta(kDoubleSize / kPointerSize);
+        } else {
+          DCHECK(op->representation() == MachineRepresentation::kFloat32);

[Benedikt Meurer, 2016/06/01 03:52:06]

Nit: DCHECK_EQ(MachineRepresentation::kFloat32, op->representation())

[bbudge, 2016/06/01 17:13:04]

Done.

+          __ vpush(i.InputFloat32Register(0));
+          frame_access_state()->IncreaseSPDelta(1);
+        }
       } else {
         __ push(i.InputRegister(0));
         frame_access_state()->IncreaseSPDelta(1);