ARM64: Use direct deoptimization exits.

src/arm64/macro-assembler-arm64.h

Index: src/arm64/macro-assembler-arm64.h
diff --git a/src/arm64/macro-assembler-arm64.h b/src/arm64/macro-assembler-arm64.h
index 0efd9e8660c1c6ea0b4380eea79661daf011a387..33135f74162784848e56edfc8f132c2c2e744bd6 100644
--- a/src/arm64/macro-assembler-arm64.h
+++ b/src/arm64/macro-assembler-arm64.h
@@ -503,7 +503,8 @@ class MacroAssembler : public Assembler {
   // Pseudo-instructions ------------------------------------------------------
 
   // Compute rd = abs(rm).
-  // This function clobbers the condition flags.
+  // This function clobbers the condition flags. On output the overflow flag is
+  // set iff the negation overflowed.
   //
   // If rm is the minimum representable value, the result is not representable.
   // Handlers for each case can be specified using the relevant labels.