Add an untagged double to transcendental cache elements. They now contain an...

src/ia32/code-stubs-ia32.cc

 // Copyright 2010 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 2548 matching lines @@
   __ test(eax, Operand(eax));
   __ j(zero, &runtime_call_clear_stack);
 #ifdef DEBUG
   // Check that the layout of cache elements match expectations.
   { TranscendentalCache::Element test_elem[2];
     char* elem_start = reinterpret_cast<char*>(&test_elem[0]);
     char* elem2_start = reinterpret_cast<char*>(&test_elem[1]);
     char* elem_in0  = reinterpret_cast<char*>(&(test_elem[0].in[0]));
     char* elem_in1  = reinterpret_cast<char*>(&(test_elem[0].in[1]));
     char* elem_out = reinterpret_cast<char*>(&(test_elem[0].output));
-    CHECK_EQ(12, elem2_start - elem_start);  // Two uint_32's and a pointer.
+    char* elem_uout = reinterpret_cast<char*>(&(test_elem[0].untagged_output));
+    CHECK_EQ(20, elem2_start - elem_start);  // Two uint_32's and a pointer.
     CHECK_EQ(0, elem_in0 - elem_start);
     CHECK_EQ(kIntSize, elem_in1 - elem_start);
     CHECK_EQ(2 * kIntSize, elem_out - elem_start);
+    CHECK_EQ(3 * kIntSize, elem_uout - elem_start);
   }
 #endif
-  // Find the address of the ecx'th entry in the cache, i.e., &eax[ecx*12].
-  __ lea(ecx, Operand(ecx, ecx, times_2, 0));
+  // Find the address of the ecx'th entry in the cache, i.e., &eax[ecx*20].
+  __ lea(ecx, Operand(ecx, ecx, times_4, 0));
   __ lea(ecx, Operand(eax, ecx, times_4, 0));
   // Check if cache matches: Double value is stored in uint32_t[2] array.
-  NearLabel cache_miss;
+  NearLabel cache_miss, allocate_cached_answer;
   __ cmp(ebx, Operand(ecx, 0));
   __ j(not_equal, &cache_miss);
   __ cmp(edx, Operand(ecx, kIntSize));
   __ j(not_equal, &cache_miss);
   // Cache hit!
-  __ mov(eax, Operand(ecx, 2 * kIntSize));
   if (tagged) {
+    __ mov(eax, Operand(ecx, 2 * kIntSize));
     __ fstp(0);
+    __ test(eax, Operand(eax));
+    __ j(zero, &allocate_cached_answer);  // The answer is cached as untagged.
     __ ret(kPointerSize);
   } else {  // UNTAGGED.
-    __ movdbl(xmm1, FieldOperand(eax, HeapNumber::kValueOffset));
+    __ movdbl(xmm1, Operand(ecx, 3 * kIntSize));
     __ Ret();
   }
 
+  __ bind(&allocate_cached_answer);
+  __ AllocateHeapNumber(eax, edi, edx, &runtime_call);
+  __ mov(ebx, Operand(ecx, 3 * kIntSize));
+  __ mov(FieldOperand(eax, HeapNumber::kValueOffset), ebx);
+  __ mov(ebx, Operand(ecx, 4 * kIntSize));
+  __ mov(FieldOperand(eax, HeapNumber::kExponentOffset), ebx);
+  __ mov(Operand(ecx, 2 * kIntSize), eax);
+  __ ret(kPointerSize);
+
   __ bind(&cache_miss);
   // Update cache with new value.
   // We are short on registers, so use no_reg as scratch.
   // This gives slightly larger code.
   if (tagged) {
     __ AllocateHeapNumber(eax, edi, no_reg, &runtime_call_clear_stack);
   } else {  // UNTAGGED.
-    __ AllocateHeapNumber(eax, edi, no_reg, &skip_cache);
     __ sub(Operand(esp), Immediate(kDoubleSize));
     __ movdbl(Operand(esp, 0), xmm1);
     __ fld_d(Operand(esp, 0));
     __ add(Operand(esp), Immediate(kDoubleSize));
   }
   GenerateOperation(masm);
   __ mov(Operand(ecx, 0), ebx);
   __ mov(Operand(ecx, kIntSize), edx);
-  __ mov(Operand(ecx, 2 * kIntSize), eax);
-  __ fstp_d(FieldOperand(eax, HeapNumber::kValueOffset));
   if (tagged) {
+    __ fst_d(FieldOperand(eax, HeapNumber::kValueOffset));
+    __ mov(Operand(ecx, 2 * kIntSize), eax);
+    __ fstp_d(Operand(ecx, 3 * kIntSize));
     __ ret(kPointerSize);
   } else {  // UNTAGGED.
-    __ movdbl(xmm1, FieldOperand(eax, HeapNumber::kValueOffset));
+    __ fstp_d(Operand(ecx, 3 * kIntSize));
+    __ movdbl(xmm1, Operand(ecx, 3 * kIntSize));
     __ Ret();
 
     // Skip cache and return answer directly, only in untagged case.
     __ bind(&skip_cache);
     __ sub(Operand(esp), Immediate(kDoubleSize));
     __ movdbl(Operand(esp, 0), xmm1);
     __ fld_d(Operand(esp, 0));
     GenerateOperation(masm);
     __ fstp_d(Operand(esp, 0));
     __ movdbl(xmm1, Operand(esp, 0));
@@ skipping 3779 matching lines @@
   // Do a tail call to the rewritten stub.
   __ jmp(Operand(edi));
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32