A64: When truncating to an int, store the result in a 64bit register

src/a64/macro-assembler-a64.h

Index: src/a64/macro-assembler-a64.h
diff --git a/src/a64/macro-assembler-a64.h b/src/a64/macro-assembler-a64.h
index c36a2e801612b8dd6b7ffc4de8ba2eca006aac7a..0c70747f7b0447dfd56df850c47316280aa33606 100644
--- a/src/a64/macro-assembler-a64.h
+++ b/src/a64/macro-assembler-a64.h
@@ -1094,13 +1094,9 @@ class MacroAssembler : public Assembler {
   // ---- Floating point helpers ----
 
   enum ECMA262ToInt32Result {
-    // Provide an untagged int32_t which can be read using result.W(). That is,
-    // the upper 32 bits of result are undefined.
-    INT32_IN_W,
-
     // Provide an untagged int32_t which can be read using the 64-bit result
     // register. The int32_t result is sign-extended.
-    INT32_IN_X,
+    INT32,
 
     // Tag the int32_t result as a smi.
     SMI
@@ -1111,7 +1107,7 @@ class MacroAssembler : public Assembler {
                       DoubleRegister input,
                       Register scratch1,
                       Register scratch2,
-                      ECMA262ToInt32Result format = INT32_IN_X);
+                      ECMA262ToInt32Result format = INT32);
 
   // As ECMA262ToInt32, but operate on a HeapNumber.
   void HeapNumberECMA262ToInt32(Register result,
@@ -1119,7 +1115,7 @@ class MacroAssembler : public Assembler {
                                 Register scratch1,
                                 Register scratch2,
                                 DoubleRegister double_scratch,
-                                ECMA262ToInt32Result format = INT32_IN_X);
+                                ECMA262ToInt32Result format = INT32);
 
   // ---- Code generation helpers ----