Generated code for substring slices in x64 and arm.

src/arm/macro-assembler-arm.h

Index: src/arm/macro-assembler-arm.h
diff --git a/src/arm/macro-assembler-arm.h b/src/arm/macro-assembler-arm.h
index 9c653adbbaebfd76c50cecbce5220b59492d0c0b..9d6635962539d7e0b38553dfb2f9feb199f18b90 100644
--- a/src/arm/macro-assembler-arm.h
+++ b/src/arm/macro-assembler-arm.h
@@ -532,6 +532,16 @@ class MacroAssembler: public Assembler {
                                Register scratch1,
                                Register scratch2,
                                Label* gc_required);
+  void AllocateTwoByteSlicedString(Register result,
+                                   Register length,
+                                   Register scratch1,
+                                   Register scratch2,
+                                   Label* gc_required);
+  void AllocateAsciiSlicedString(Register result,
+                                 Register length,
+                                 Register scratch1,
+                                 Register scratch2,
+                                 Label* gc_required);
 
   // Allocates a heap number or jumps to the gc_required label if the young
   // space is full and a scavenge is needed. All registers are clobbered also