Add MathPowStub to x64 platform, and fix error in stub on ia32 platform.

src/x64/code-stubs-x64.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 1999 matching lines @@
       }
       __ SmiNeg(rax, rax, &done);
       __ jmp(&slow);  // zero, if not handled above, and Smi::kMinValue.
 
       // Try floating point case.
       __ bind(&try_float);
     } else if (FLAG_debug_code) {
       __ AbortIfSmi(rax);
     }
 
-    __ movq(rdx, FieldOperand(rax, HeapObject::kMapOffset));
-    __ CompareRoot(rdx, Heap::kHeapNumberMapRootIndex);
+    __ CompareRoot(FieldOperand(rax, HeapObject::kMapOffset),
+                   Heap::kHeapNumberMapRootIndex);
     __ j(not_equal, &slow);
     // Operand is a float, negate its value by flipping sign bit.
     __ movq(rdx, FieldOperand(rax, HeapNumber::kValueOffset));
     __ movq(kScratchRegister, Immediate(0x01));
     __ shl(kScratchRegister, Immediate(63));
     __ xor_(rdx, kScratchRegister);  // Flip sign.
     // rdx is value to store.
     if (overwrite_ == UNARY_OVERWRITE) {
       __ movq(FieldOperand(rax, HeapNumber::kValueOffset), rdx);
     } else {
       __ AllocateHeapNumber(rcx, rbx, &slow);
       // rcx: allocated 'empty' number
       __ movq(FieldOperand(rcx, HeapNumber::kValueOffset), rdx);
       __ movq(rax, rcx);
     }
   } else if (op_ == Token::BIT_NOT) {
     if (include_smi_code_) {
       Label try_float;
       __ JumpIfNotSmi(rax, &try_float);
       __ SmiNot(rax, rax);
       __ jmp(&done);
       // Try floating point case.
       __ bind(&try_float);
     } else if (FLAG_debug_code) {
       __ AbortIfSmi(rax);
     }
 
     // Check if the operand is a heap number.
-    __ movq(rdx, FieldOperand(rax, HeapObject::kMapOffset));
-    __ CompareRoot(rdx, Heap::kHeapNumberMapRootIndex);
+    __ CompareRoot(FieldOperand(rax, HeapObject::kMapOffset),
+                   Heap::kHeapNumberMapRootIndex);
     __ j(not_equal, &slow);
 
     // Convert the heap number in rax to an untagged integer in rcx.
     IntegerConvert(masm, rax, rax);
 
     // Do the bitwise operation and smi tag the result.
     __ notl(rax);
     __ Integer32ToSmi(rax, rax);
   }
 
@@ skipping 12 matching lines @@
       break;
     case Token::BIT_NOT:
       __ InvokeBuiltin(Builtins::BIT_NOT, JUMP_FUNCTION);
       break;
     default:
       UNREACHABLE();
   }
 }
 
 
+void MathPowStub::Generate(MacroAssembler* masm) {
+  // Registers are used as follows:
+  // rdx = base
+  // rax = exponent
+  // rcx = temporary, result
+
+  Label allocate_return, call_runtime;
+
+  // Load input parameters.
+  __ movq(rdx, Operand(rsp, 2 * kPointerSize));
+  __ movq(rax, Operand(rsp, 1 * kPointerSize));
+
+  // Save 1 in xmm3 - we need this several times later on.
+  __ movl(rcx, Immediate(1));
+  __ cvtlsi2sd(xmm3, rcx);
+
+  Label exponent_nonsmi;
+  Label base_nonsmi;
+  // If the exponent is a heap number go to that specific case.
+  __ JumpIfNotSmi(rax, &exponent_nonsmi);
+  __ JumpIfNotSmi(rdx, &base_nonsmi);
+
+  // Optimized version when both exponent and base are smis.
+  Label powi;
+  __ SmiToInteger32(rdx, rdx);
+  __ cvtlsi2sd(xmm0, rdx);
+  __ jmp(&powi);
+  // Exponent is a smi and base is a heapnumber.
+  __ bind(&base_nonsmi);
+  __ CompareRoot(FieldOperand(rdx, HeapObject::kMapOffset),
+                 Heap::kHeapNumberMapRootIndex);
+  __ j(not_equal, &call_runtime);
+
+  __ movsd(xmm0, FieldOperand(rdx, HeapNumber::kValueOffset));
+
+  // Optimized version of pow if exponent is a smi.
+  // xmm0 contains the base.
+  __ bind(&powi);
+  __ SmiToInteger32(rax, rax);
+
+  // Save exponent in base as we need to check if exponent is negative later.
+  // We know that base and exponent are in different registers.
+  __ movq(rdx, rax);
+
+  // Get absolute value of exponent.
+  NearLabel no_neg;
+  __ cmpl(rax, Immediate(0));
+  __ j(greater_equal, &no_neg);
+  __ negl(rax);
+  __ bind(&no_neg);
+
+  // Load xmm1 with 1.
+  __ movsd(xmm1, xmm3);
+  NearLabel while_true;
+  NearLabel no_multiply;
+
+  __ bind(&while_true);
+  __ shrl(rax, Immediate(1));
+  __ j(not_carry, &no_multiply);
+  __ mulsd(xmm1, xmm0);
+  __ bind(&no_multiply);
+  __ mulsd(xmm0, xmm0);
+  __ j(not_zero, &while_true);
+
+  // Base has the original value of the exponent - if the exponent  is
+  // negative return 1/result.
+  __ testl(rdx, rdx);
+  __ j(positive, &allocate_return);
+  // Special case if xmm1 has reached infinity.
+  __ divsd(xmm3, xmm1);
+  __ movsd(xmm1, xmm3);
+  __ xorpd(xmm0, xmm0);
+  __ ucomisd(xmm0, xmm1);
+  __ j(equal, &call_runtime);
+
+  __ jmp(&allocate_return);
+
+  // Exponent (or both) is a heapnumber - no matter what we should now work
+  // on doubles.
+  __ bind(&exponent_nonsmi);
+  __ CompareRoot(FieldOperand(rax, HeapObject::kMapOffset),
+                 Heap::kHeapNumberMapRootIndex);
+  __ j(not_equal, &call_runtime);
+  __ movsd(xmm1, FieldOperand(rax, HeapNumber::kValueOffset));
+  // Test if exponent is nan.
+  __ ucomisd(xmm1, xmm1);
+  __ j(parity_even, &call_runtime);
+
+  NearLabel base_not_smi;
+  NearLabel handle_special_cases;
+  __ JumpIfNotSmi(rdx, &base_not_smi);
+  __ SmiToInteger32(rdx, rdx);
+  __ cvtlsi2sd(xmm0, rdx);
+  __ jmp(&handle_special_cases);
+
+  __ bind(&base_not_smi);
+  __ CompareRoot(FieldOperand(rdx, HeapObject::kMapOffset),
+                 Heap::kHeapNumberMapRootIndex);
+  __ j(not_equal, &call_runtime);
+  __ movl(rcx, FieldOperand(rdx, HeapNumber::kExponentOffset));
+  __ andl(rcx, Immediate(HeapNumber::kExponentMask));
+  __ cmpl(rcx, Immediate(HeapNumber::kExponentMask));
+  // base is NaN or +/-Infinity
+  __ j(greater_equal, &call_runtime);
+  __ movsd(xmm0, FieldOperand(rdx, HeapNumber::kValueOffset));
+
+  // base is in xmm0 and exponent is in xmm1.
+  __ bind(&handle_special_cases);
+  NearLabel not_minus_half;
+  // Test for -0.5.
+  // Load xmm2 with -0.5.
+  __ movq(rcx, V8_UINT64_C(0xBFE0000000000000), RelocInfo::NONE);
+  __ movq(xmm2, rcx);
+  // xmm2 now has -0.5.
+  __ ucomisd(xmm2, xmm1);
+  __ j(not_equal, &not_minus_half);
+
+  // Calculates reciprocal of square root.
+  // sqrtsd returns -0 when input is -0.  ECMA spec requires +0.
+  __ xorpd(xmm1, xmm1);
+  __ addsd(xmm1, xmm0);
+  __ sqrtsd(xmm1, xmm1);
+  __ divsd(xmm3, xmm1);
+  __ movsd(xmm1, xmm3);
+  __ jmp(&allocate_return);
+
+  // Test for 0.5.
+  __ bind(&not_minus_half);
+  // Load xmm2 with 0.5.
+  // Since xmm3 is 1 and xmm2 is -0.5 this is simply xmm2 + xmm3.
+  __ addsd(xmm2, xmm3);
+  // xmm2 now has 0.5.
+  __ ucomisd(xmm2, xmm1);
+  __ j(not_equal, &call_runtime);
+  // Calculates square root.
+  // sqrtsd returns -0 when input is -0.  ECMA spec requires +0.
+  __ xorpd(xmm1, xmm1);
+  __ addsd(xmm1, xmm0);
+  __ sqrtsd(xmm1, xmm1);
+
+  __ bind(&allocate_return);
+  __ AllocateHeapNumber(rcx, rax, &call_runtime);
+  __ movsd(FieldOperand(rcx, HeapNumber::kValueOffset), xmm1);
+  __ movq(rax, rcx);
+  __ ret(2 * kPointerSize);
+
+  __ bind(&call_runtime);
+  __ TailCallRuntime(Runtime::kMath_pow_cfunction, 2, 1);
+}
+
+
 void ArgumentsAccessStub::GenerateReadElement(MacroAssembler* masm) {
   // The key is in rdx and the parameter count is in rax.
 
   // The displacement is used for skipping the frame pointer on the
   // stack. It is the offset of the last parameter (if any) relative
   // to the frame pointer.
   static const int kDisplacement = 1 * kPointerSize;
 
   // Check that the key is a smi.
   Label slow;
@@ skipping 2841 matching lines @@
           FieldOperand(elements, PixelArray::kExternalPointerOffset));
   __ movb(Operand(external_pointer, untagged_key, times_1, 0), untagged_value);
   __ ret(0);  // Return value in eax.
 }
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64