MIPS: Use shift and add instead of mul on ARM for integer hash. This is a...

MIPS: Use shift and add instead of mul on ARM for integer hash.  This is a commit of http://codereview.chromium.org/9192011/ for Daniel Kalmar

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10442 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/mips/macro-assembler-mips.cc

@@ -444,8 +444,10 @@ void MacroAssembler::GetNumberHash(Register reg0, Register scratch) {
   xor_(reg0, reg0, at);
 
   // hash = hash * 2057;
-  li(scratch, Operand(2057));
-  mul(reg0, reg0, scratch);
+  sll(scratch, reg0, 11);
+  sll(at, reg0, 3);
+  addu(reg0, reg0, at);
+  addu(reg0, reg0, scratch);
 
   // hash = hash ^ (hash >> 16);
   srl(at, reg0, 16);