Backport @10366 to 3.6

src/ia32/macro-assembler-ia32.cc

Index: src/ia32/macro-assembler-ia32.cc
===================================================================
--- src/ia32/macro-assembler-ia32.cc	(revision 10379)
+++ src/ia32/macro-assembler-ia32.cc	(working copy)
@@ -752,6 +752,49 @@
 }
 
 
+// Compute the hash code from the untagged key.  This must be kept in sync
+// with ComputeIntegerHash in utils.h.
+//
+// Note: r0 will contain hash code
+void MacroAssembler::GetNumberHash(Register r0, Register scratch) {
+  // Xor original key with a seed.
+  if (Serializer::enabled()) {
+    ExternalReference roots_address =
+        ExternalReference::roots_address(isolate());
+    mov(scratch, Immediate(Heap::kHashSeedRootIndex));

[Erik Corry, 2012/01/11 10:20:35]

There's a missing SmiUntag here.  Probably it doesn't matter because there are
no number dictionaries in the snapshot, but we should fix it anyway.

I will fix it on bleeding edge.

+    xor_(r0, Operand::StaticArray(scratch,
+                                 times_pointer_size,

[Erik Corry, 2012/01/11 10:20:35]

Somehow the indentation got borked here.

+                                 roots_address));
+  } else {
+    int32_t seed = isolate()->heap()->HashSeed();
+    xor_(r0, seed);
+  }
+
+  // hash = ~hash + (hash << 15);
+  mov(scratch, r0);
+  not_(r0);
+  shl(scratch, 15);
+  add(r0, Operand(scratch));
+  // hash = hash ^ (hash >> 12);
+  mov(scratch, r0);
+  shr(scratch, 12);
+  xor_(r0, Operand(scratch));
+  // hash = hash + (hash << 2);
+  lea(r0, Operand(r0, r0, times_4, 0));
+  // hash = hash ^ (hash >> 4);
+  mov(scratch, r0);
+  shr(scratch, 4);
+  xor_(r0, Operand(scratch));
+  // hash = hash * 2057;
+  imul(r0, r0, 2057);
+  // hash = hash ^ (hash >> 16);
+  mov(scratch, r0);
+  shr(scratch, 16);
+  xor_(r0, Operand(scratch));
+}
+
+
+
 void MacroAssembler::LoadFromNumberDictionary(Label* miss,
                                               Register elements,
                                               Register key,
@@ -777,30 +820,7 @@
 
   Label done;
 
-  // Compute the hash code from the untagged key.  This must be kept in sync
-  // with ComputeIntegerHash in utils.h.
-  //
-  // hash = ~hash + (hash << 15);
-  mov(r1, r0);
-  not_(r0);
-  shl(r1, 15);
-  add(r0, Operand(r1));
-  // hash = hash ^ (hash >> 12);
-  mov(r1, r0);
-  shr(r1, 12);
-  xor_(r0, Operand(r1));
-  // hash = hash + (hash << 2);
-  lea(r0, Operand(r0, r0, times_4, 0));
-  // hash = hash ^ (hash >> 4);
-  mov(r1, r0);
-  shr(r1, 4);
-  xor_(r0, Operand(r1));
-  // hash = hash * 2057;
-  imul(r0, r0, 2057);
-  // hash = hash ^ (hash >> 16);
-  mov(r1, r0);
-  shr(r1, 16);
-  xor_(r0, Operand(r1));
+  GetNumberHash(r0, r1);
 
   // Compute capacity mask.
   mov(r1, FieldOperand(elements, NumberDictionary::kCapacityOffset));