Backport @10366 to 3.6

src/arm/macro-assembler-arm.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1319 matching lines @@
 
   ldr(scratch, FieldMemOperand(scratch, token_offset));
   ldr(ip, FieldMemOperand(ip, token_offset));
   cmp(scratch, Operand(ip));
   b(ne, miss);
 
   bind(&same_contexts);
 }
 
 
+void MacroAssembler::GetNumberHash(Register t0, Register scratch) {
+  // First of all we assign the hash seed to scratch.
+  LoadRoot(scratch, Heap::kHashSeedRootIndex);
+  SmiUntag(scratch);
+
+  // Xor original key with a seed.
+  eor(t0, t0, Operand(scratch));
+
+  // Compute the hash code from the untagged key.  This must be kept in sync
+  // with ComputeIntegerHash in utils.h.
+  //
+  // hash = ~hash + (hash << 15);
+  mvn(scratch, Operand(t0));
+  add(t0, scratch, Operand(t0, LSL, 15));
+  // hash = hash ^ (hash >> 12);
+  eor(t0, t0, Operand(t0, LSR, 12));
+  // hash = hash + (hash << 2);
+  add(t0, t0, Operand(t0, LSL, 2));
+  // hash = hash ^ (hash >> 4);
+  eor(t0, t0, Operand(t0, LSR, 4));
+  // hash = hash * 2057;
+  mov(scratch, Operand(2057));
+  mul(t0, t0, scratch);

[Erik Corry, 2012/01/19 15:35:00]

This looks like a missing merge, but no big deal.

+  // hash = hash ^ (hash >> 16);
+  eor(t0, t0, Operand(t0, LSR, 16));
+}
+
+
 void MacroAssembler::LoadFromNumberDictionary(Label* miss,
                                               Register elements,
                                               Register key,
                                               Register result,
                                               Register t0,
                                               Register t1,
                                               Register t2) {
   // Register use:
   //
   // elements - holds the slow-case elements of the receiver on entry.
   //            Unchanged unless 'result' is the same register.
   //
   // key      - holds the smi key on entry.
   //            Unchanged unless 'result' is the same register.
   //
   // result   - holds the result on exit if the load succeeded.
   //            Allowed to be the same as 'key' or 'result'.
   //            Unchanged on bailout so 'key' or 'result' can be used
   //            in further computation.
   //
   // Scratch registers:
   //
   // t0 - holds the untagged key on entry and holds the hash once computed.
   //
   // t1 - used to hold the capacity mask of the dictionary
   //
   // t2 - used for the index into the dictionary.
   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);
-  mvn(t1, Operand(t0));
-  add(t0, t1, Operand(t0, LSL, 15));
-  // hash = hash ^ (hash >> 12);
-  eor(t0, t0, Operand(t0, LSR, 12));
-  // hash = hash + (hash << 2);
-  add(t0, t0, Operand(t0, LSL, 2));
-  // hash = hash ^ (hash >> 4);
-  eor(t0, t0, Operand(t0, LSR, 4));
-  // hash = hash * 2057;
-  mov(t1, Operand(2057));
-  mul(t0, t0, t1);
-  // hash = hash ^ (hash >> 16);
-  eor(t0, t0, Operand(t0, LSR, 16));
+  GetNumberHash(t0, t1);
 
   // Compute the capacity mask.
-  ldr(t1, FieldMemOperand(elements, NumberDictionary::kCapacityOffset));
+  ldr(t1, FieldMemOperand(elements, SeededNumberDictionary::kCapacityOffset));
   mov(t1, Operand(t1, ASR, kSmiTagSize));  // convert smi to int
   sub(t1, t1, Operand(1));
 
   // Generate an unrolled loop that performs a few probes before giving up.
   static const int kProbes = 4;
   for (int i = 0; i < kProbes; i++) {
     // Use t2 for index calculations and keep the hash intact in t0.
     mov(t2, t0);
     // Compute the masked index: (hash + i + i * i) & mask.
     if (i > 0) {
-      add(t2, t2, Operand(NumberDictionary::GetProbeOffset(i)));
+      add(t2, t2, Operand(SeededNumberDictionary::GetProbeOffset(i)));
     }
     and_(t2, t2, Operand(t1));
 
     // Scale the index by multiplying by the element size.
-    ASSERT(NumberDictionary::kEntrySize == 3);
+    ASSERT(SeededNumberDictionary::kEntrySize == 3);
     add(t2, t2, Operand(t2, LSL, 1));  // t2 = t2 * 3
 
     // Check if the key is identical to the name.
     add(t2, elements, Operand(t2, LSL, kPointerSizeLog2));
-    ldr(ip, FieldMemOperand(t2, NumberDictionary::kElementsStartOffset));
+    ldr(ip, FieldMemOperand(t2, SeededNumberDictionary::kElementsStartOffset));
     cmp(key, Operand(ip));
     if (i != kProbes - 1) {
       b(eq, &done);
     } else {
       b(ne, miss);
     }
   }
 
   bind(&done);
   // Check that the value is a normal property.
   // t2: elements + (index * kPointerSize)
   const int kDetailsOffset =
-      NumberDictionary::kElementsStartOffset + 2 * kPointerSize;
+      SeededNumberDictionary::kElementsStartOffset + 2 * kPointerSize;
   ldr(t1, FieldMemOperand(t2, kDetailsOffset));
   tst(t1, Operand(Smi::FromInt(PropertyDetails::TypeField::kMask)));
   b(ne, miss);
 
   // Get the value at the masked, scaled index and return.
   const int kValueOffset =
-      NumberDictionary::kElementsStartOffset + kPointerSize;
+      SeededNumberDictionary::kElementsStartOffset + kPointerSize;
   ldr(result, FieldMemOperand(t2, kValueOffset));
 }
 
 
 void MacroAssembler::AllocateInNewSpace(int object_size,
                                         Register result,
                                         Register scratch1,
                                         Register scratch2,
                                         Label* gc_required,
                                         AllocationFlags flags) {
@@ skipping 1829 matching lines @@
 void CodePatcher::EmitCondition(Condition cond) {
   Instr instr = Assembler::instr_at(masm_.pc_);
   instr = (instr & ~kCondMask) | cond;
   masm_.emit(instr);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM