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Unified Diff: src/a64/codegen-a64.cc

Issue 148293020: Merge experimental/a64 to bleeding_edge. (Closed) Base URL: https://v8.googlecode.com/svn/branches/bleeding_edge
Patch Set: Remove ARM from OWNERS Created 6 years, 10 months ago
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Index: src/a64/codegen-a64.cc
diff --git a/src/a64/codegen-a64.cc b/src/a64/codegen-a64.cc
new file mode 100644
index 0000000000000000000000000000000000000000..7ce1bfae09e960f9ff807bda3c46d2ca5f0adbdf
--- /dev/null
+++ b/src/a64/codegen-a64.cc
@@ -0,0 +1,614 @@
+// Copyright 2013 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
+// with the distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived
+// from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include "v8.h"
+
+#if V8_TARGET_ARCH_A64
+
+#include "codegen.h"
+#include "macro-assembler.h"
+#include "simulator-a64.h"
+
+namespace v8 {
+namespace internal {
+
+#define __ ACCESS_MASM(masm)
+
+#if defined(USE_SIMULATOR)
+byte* fast_exp_a64_machine_code = NULL;
+double fast_exp_simulator(double x) {
+ Simulator * simulator = Simulator::current(Isolate::Current());
+ return simulator->CallDouble(fast_exp_a64_machine_code,
+ Simulator::CallArgument(x),
+ Simulator::CallArgument::End());
+}
+#endif
+
+
+UnaryMathFunction CreateExpFunction() {
+ if (!FLAG_fast_math) return &std::exp;
+
+ // Use the Math.exp implemetation in MathExpGenerator::EmitMathExp() to create
+ // an AAPCS64-compliant exp() function. This will be faster than the C
+ // library's exp() function, but probably less accurate.
+ size_t actual_size;
+ byte* buffer = static_cast<byte*>(OS::Allocate(1 * KB, &actual_size, true));
+ if (buffer == NULL) return &std::exp;
+
+ ExternalReference::InitializeMathExpData();
+ MacroAssembler masm(NULL, buffer, static_cast<int>(actual_size));
+ masm.SetStackPointer(csp);
+
+ // The argument will be in d0 on entry.
+ DoubleRegister input = d0;
+ // Use other caller-saved registers for all other values.
+ DoubleRegister result = d1;
+ DoubleRegister double_temp1 = d2;
+ DoubleRegister double_temp2 = d3;
+ Register temp1 = x10;
+ Register temp2 = x11;
+ Register temp3 = x12;
+
+ MathExpGenerator::EmitMathExp(&masm, input, result,
+ double_temp1, double_temp2,
+ temp1, temp2, temp3);
+ // Move the result to the return register.
+ masm.Fmov(d0, result);
+ masm.Ret();
+
+ CodeDesc desc;
+ masm.GetCode(&desc);
+ ASSERT(!RelocInfo::RequiresRelocation(desc));
+
+ CPU::FlushICache(buffer, actual_size);
+ OS::ProtectCode(buffer, actual_size);
+
+#if !defined(USE_SIMULATOR)
+ return FUNCTION_CAST<UnaryMathFunction>(buffer);
+#else
+ fast_exp_a64_machine_code = buffer;
+ return &fast_exp_simulator;
+#endif
+}
+
+
+UnaryMathFunction CreateSqrtFunction() {
+ return &std::sqrt;
+}
+
+
+// -------------------------------------------------------------------------
+// Platform-specific RuntimeCallHelper functions.
+
+void StubRuntimeCallHelper::BeforeCall(MacroAssembler* masm) const {
+ masm->EnterFrame(StackFrame::INTERNAL);
+ ASSERT(!masm->has_frame());
+ masm->set_has_frame(true);
+}
+
+
+void StubRuntimeCallHelper::AfterCall(MacroAssembler* masm) const {
+ masm->LeaveFrame(StackFrame::INTERNAL);
+ ASSERT(masm->has_frame());
+ masm->set_has_frame(false);
+}
+
+
+// -------------------------------------------------------------------------
+// Code generators
+
+void ElementsTransitionGenerator::GenerateMapChangeElementsTransition(
+ MacroAssembler* masm, AllocationSiteMode mode,
+ Label* allocation_memento_found) {
+ // ----------- S t a t e -------------
+ // -- x2 : receiver
+ // -- x3 : target map
+ // -----------------------------------
+ Register receiver = x2;
+ Register map = x3;
+
+ if (mode == TRACK_ALLOCATION_SITE) {
+ ASSERT(allocation_memento_found != NULL);
+ __ JumpIfJSArrayHasAllocationMemento(receiver, x10, x11,
+ allocation_memento_found);
+ }
+
+ // Set transitioned map.
+ __ Str(map, FieldMemOperand(receiver, HeapObject::kMapOffset));
+ __ RecordWriteField(receiver,
+ HeapObject::kMapOffset,
+ map,
+ x10,
+ kLRHasNotBeenSaved,
+ kDontSaveFPRegs,
+ EMIT_REMEMBERED_SET,
+ OMIT_SMI_CHECK);
+}
+
+
+void ElementsTransitionGenerator::GenerateSmiToDouble(
+ MacroAssembler* masm, AllocationSiteMode mode, Label* fail) {
+ ASM_LOCATION("ElementsTransitionGenerator::GenerateSmiToDouble");
+ // ----------- S t a t e -------------
+ // -- lr : return address
+ // -- x0 : value
+ // -- x1 : key
+ // -- x2 : receiver
+ // -- x3 : target map, scratch for subsequent call
+ // -----------------------------------
+ Register receiver = x2;
+ Register target_map = x3;
+
+ Label gc_required, only_change_map;
+
+ if (mode == TRACK_ALLOCATION_SITE) {
+ __ JumpIfJSArrayHasAllocationMemento(receiver, x10, x11, fail);
+ }
+
+ // Check for empty arrays, which only require a map transition and no changes
+ // to the backing store.
+ Register elements = x4;
+ __ Ldr(elements, FieldMemOperand(receiver, JSObject::kElementsOffset));
+ __ JumpIfRoot(elements, Heap::kEmptyFixedArrayRootIndex, &only_change_map);
+
+ __ Push(lr);
+ Register length = x5;
+ __ Ldrsw(length, UntagSmiFieldMemOperand(elements,
+ FixedArray::kLengthOffset));
+
+ // Allocate new FixedDoubleArray.
+ Register array_size = x6;
+ Register array = x7;
+ __ Lsl(array_size, length, kDoubleSizeLog2);
+ __ Add(array_size, array_size, FixedDoubleArray::kHeaderSize);
+ __ Allocate(array_size, array, x10, x11, &gc_required, DOUBLE_ALIGNMENT);
+ // Register array is non-tagged heap object.
+
+ // Set the destination FixedDoubleArray's length and map.
+ Register map_root = x6;
+ __ LoadRoot(map_root, Heap::kFixedDoubleArrayMapRootIndex);
+ __ SmiTag(x11, length);
+ __ Str(x11, MemOperand(array, FixedDoubleArray::kLengthOffset));
+ __ Str(map_root, MemOperand(array, HeapObject::kMapOffset));
+
+ __ Str(target_map, FieldMemOperand(receiver, HeapObject::kMapOffset));
+ __ RecordWriteField(receiver, HeapObject::kMapOffset, target_map, x6,
+ kLRHasBeenSaved, kDontSaveFPRegs, OMIT_REMEMBERED_SET,
+ OMIT_SMI_CHECK);
+
+ // Replace receiver's backing store with newly created FixedDoubleArray.
+ __ Add(x10, array, kHeapObjectTag);
+ __ Str(x10, FieldMemOperand(receiver, JSObject::kElementsOffset));
+ __ RecordWriteField(receiver, JSObject::kElementsOffset, x10,
+ x6, kLRHasBeenSaved, kDontSaveFPRegs,
+ EMIT_REMEMBERED_SET, OMIT_SMI_CHECK);
+
+ // Prepare for conversion loop.
+ Register src_elements = x10;
+ Register dst_elements = x11;
+ Register dst_end = x12;
+ __ Add(src_elements, elements, FixedArray::kHeaderSize - kHeapObjectTag);
+ __ Add(dst_elements, array, FixedDoubleArray::kHeaderSize);
+ __ Add(dst_end, dst_elements, Operand(length, LSL, kDoubleSizeLog2));
+
+ FPRegister nan_d = d1;
+ __ Fmov(nan_d, rawbits_to_double(kHoleNanInt64));
+
+ Label entry, done;
+ __ B(&entry);
+
+ __ Bind(&only_change_map);
+ __ Str(target_map, FieldMemOperand(receiver, HeapObject::kMapOffset));
+ __ RecordWriteField(receiver, HeapObject::kMapOffset, target_map, x6,
+ kLRHasNotBeenSaved, kDontSaveFPRegs, OMIT_REMEMBERED_SET,
+ OMIT_SMI_CHECK);
+ __ B(&done);
+
+ // Call into runtime if GC is required.
+ __ Bind(&gc_required);
+ __ Pop(lr);
+ __ B(fail);
+
+ // Iterate over the array, copying and coverting smis to doubles. If an
+ // element is non-smi, write a hole to the destination.
+ {
+ Label loop;
+ __ Bind(&loop);
+ __ Ldr(x13, MemOperand(src_elements, kPointerSize, PostIndex));
+ __ SmiUntagToDouble(d0, x13, kSpeculativeUntag);
+ __ Tst(x13, kSmiTagMask);
+ __ Fcsel(d0, d0, nan_d, eq);
+ __ Str(d0, MemOperand(dst_elements, kDoubleSize, PostIndex));
+
+ __ Bind(&entry);
+ __ Cmp(dst_elements, dst_end);
+ __ B(lt, &loop);
+ }
+
+ __ Pop(lr);
+ __ Bind(&done);
+}
+
+
+void ElementsTransitionGenerator::GenerateDoubleToObject(
+ MacroAssembler* masm, AllocationSiteMode mode, Label* fail) {
+ ASM_LOCATION("ElementsTransitionGenerator::GenerateDoubleToObject");
+ // ----------- S t a t e -------------
+ // -- x0 : value
+ // -- x1 : key
+ // -- x2 : receiver
+ // -- lr : return address
+ // -- x3 : target map, scratch for subsequent call
+ // -- x4 : scratch (elements)
+ // -----------------------------------
+ Register value = x0;
+ Register key = x1;
+ Register receiver = x2;
+ Register target_map = x3;
+
+ if (mode == TRACK_ALLOCATION_SITE) {
+ __ JumpIfJSArrayHasAllocationMemento(receiver, x10, x11, fail);
+ }
+
+ // Check for empty arrays, which only require a map transition and no changes
+ // to the backing store.
+ Label only_change_map;
+ Register elements = x4;
+ __ Ldr(elements, FieldMemOperand(receiver, JSObject::kElementsOffset));
+ __ JumpIfRoot(elements, Heap::kEmptyFixedArrayRootIndex, &only_change_map);
+
+ __ Push(lr);
+ // TODO(all): These registers may not need to be pushed. Examine
+ // RecordWriteStub and check whether it's needed.
+ __ Push(target_map, receiver, key, value);
+ Register length = x5;
+ __ Ldrsw(length, UntagSmiFieldMemOperand(elements,
+ FixedArray::kLengthOffset));
+
+ // Allocate new FixedArray.
+ Register array_size = x6;
+ Register array = x7;
+ Label gc_required;
+ __ Mov(array_size, FixedDoubleArray::kHeaderSize);
+ __ Add(array_size, array_size, Operand(length, LSL, kPointerSizeLog2));
+ __ Allocate(array_size, array, x10, x11, &gc_required, NO_ALLOCATION_FLAGS);
+
+ // Set destination FixedDoubleArray's length and map.
+ Register map_root = x6;
+ __ LoadRoot(map_root, Heap::kFixedArrayMapRootIndex);
+ __ SmiTag(x11, length);
+ __ Str(x11, MemOperand(array, FixedDoubleArray::kLengthOffset));
+ __ Str(map_root, MemOperand(array, HeapObject::kMapOffset));
+
+ // Prepare for conversion loop.
+ Register src_elements = x10;
+ Register dst_elements = x11;
+ Register dst_end = x12;
+ __ Add(src_elements, elements,
+ FixedDoubleArray::kHeaderSize - kHeapObjectTag);
+ __ Add(dst_elements, array, FixedArray::kHeaderSize);
+ __ Add(array, array, kHeapObjectTag);
+ __ Add(dst_end, dst_elements, Operand(length, LSL, kPointerSizeLog2));
+
+ Register the_hole = x14;
+ Register heap_num_map = x15;
+ __ LoadRoot(the_hole, Heap::kTheHoleValueRootIndex);
+ __ LoadRoot(heap_num_map, Heap::kHeapNumberMapRootIndex);
+
+ Label entry;
+ __ B(&entry);
+
+ // Call into runtime if GC is required.
+ __ Bind(&gc_required);
+ __ Pop(value, key, receiver, target_map);
+ __ Pop(lr);
+ __ B(fail);
+
+ {
+ Label loop, convert_hole;
+ __ Bind(&loop);
+ __ Ldr(x13, MemOperand(src_elements, kPointerSize, PostIndex));
+ __ Cmp(x13, kHoleNanInt64);
+ __ B(eq, &convert_hole);
+
+ // Non-hole double, copy value into a heap number.
+ Register heap_num = x5;
+ __ AllocateHeapNumber(heap_num, &gc_required, x6, x4, heap_num_map);
+ __ Str(x13, FieldMemOperand(heap_num, HeapNumber::kValueOffset));
+ __ Mov(x13, dst_elements);
+ __ Str(heap_num, MemOperand(dst_elements, kPointerSize, PostIndex));
+ __ RecordWrite(array, x13, heap_num, kLRHasBeenSaved, kDontSaveFPRegs,
+ EMIT_REMEMBERED_SET, OMIT_SMI_CHECK);
+
+ __ B(&entry);
+
+ // Replace the-hole NaN with the-hole pointer.
+ __ Bind(&convert_hole);
+ __ Str(the_hole, MemOperand(dst_elements, kPointerSize, PostIndex));
+
+ __ Bind(&entry);
+ __ Cmp(dst_elements, dst_end);
+ __ B(lt, &loop);
+ }
+
+ __ Pop(value, key, receiver, target_map);
+ // Replace receiver's backing store with newly created and filled FixedArray.
+ __ Str(array, FieldMemOperand(receiver, JSObject::kElementsOffset));
+ __ RecordWriteField(receiver, JSObject::kElementsOffset, array, x13,
+ kLRHasBeenSaved, kDontSaveFPRegs, EMIT_REMEMBERED_SET,
+ OMIT_SMI_CHECK);
+ __ Pop(lr);
+
+ __ Bind(&only_change_map);
+ __ Str(target_map, FieldMemOperand(receiver, HeapObject::kMapOffset));
+ __ RecordWriteField(receiver, HeapObject::kMapOffset, target_map, x13,
+ kLRHasNotBeenSaved, kDontSaveFPRegs, OMIT_REMEMBERED_SET,
+ OMIT_SMI_CHECK);
+}
+
+
+bool Code::IsYoungSequence(byte* sequence) {
+ return MacroAssembler::IsYoungSequence(sequence);
+}
+
+
+void Code::GetCodeAgeAndParity(byte* sequence, Age* age,
+ MarkingParity* parity) {
+ if (IsYoungSequence(sequence)) {
+ *age = kNoAgeCodeAge;
+ *parity = NO_MARKING_PARITY;
+ } else {
+ byte* target = sequence + kCodeAgeStubEntryOffset;
+ Code* stub = GetCodeFromTargetAddress(Memory::Address_at(target));
+ GetCodeAgeAndParity(stub, age, parity);
+ }
+}
+
+
+void Code::PatchPlatformCodeAge(Isolate* isolate,
+ byte* sequence,
+ Code::Age age,
+ MarkingParity parity) {
+ PatchingAssembler patcher(sequence, kCodeAgeSequenceSize / kInstructionSize);
+ if (age == kNoAgeCodeAge) {
+ MacroAssembler::EmitFrameSetupForCodeAgePatching(&patcher);
+ } else {
+ Code * stub = GetCodeAgeStub(isolate, age, parity);
+ MacroAssembler::EmitCodeAgeSequence(&patcher, stub);
+ }
+}
+
+
+void StringCharLoadGenerator::Generate(MacroAssembler* masm,
+ Register string,
+ Register index,
+ Register result,
+ Label* call_runtime) {
+ // Fetch the instance type of the receiver into result register.
+ __ Ldr(result, FieldMemOperand(string, HeapObject::kMapOffset));
+ __ Ldrb(result, FieldMemOperand(result, Map::kInstanceTypeOffset));
+
+ // We need special handling for indirect strings.
+ Label check_sequential;
+ __ TestAndBranchIfAllClear(result, kIsIndirectStringMask, &check_sequential);
+
+ // Dispatch on the indirect string shape: slice or cons.
+ Label cons_string;
+ __ TestAndBranchIfAllClear(result, kSlicedNotConsMask, &cons_string);
+
+ // Handle slices.
+ Label indirect_string_loaded;
+ __ Ldrsw(result,
+ UntagSmiFieldMemOperand(string, SlicedString::kOffsetOffset));
+ __ Ldr(string, FieldMemOperand(string, SlicedString::kParentOffset));
+ __ Add(index, index, result);
+ __ B(&indirect_string_loaded);
+
+ // Handle cons strings.
+ // Check whether the right hand side is the empty string (i.e. if
+ // this is really a flat string in a cons string). If that is not
+ // the case we would rather go to the runtime system now to flatten
+ // the string.
+ __ Bind(&cons_string);
+ __ Ldr(result, FieldMemOperand(string, ConsString::kSecondOffset));
+ __ JumpIfNotRoot(result, Heap::kempty_stringRootIndex, call_runtime);
+ // Get the first of the two strings and load its instance type.
+ __ Ldr(string, FieldMemOperand(string, ConsString::kFirstOffset));
+
+ __ Bind(&indirect_string_loaded);
+ __ Ldr(result, FieldMemOperand(string, HeapObject::kMapOffset));
+ __ Ldrb(result, FieldMemOperand(result, Map::kInstanceTypeOffset));
+
+ // Distinguish sequential and external strings. Only these two string
+ // representations can reach here (slices and flat cons strings have been
+ // reduced to the underlying sequential or external string).
+ Label external_string, check_encoding;
+ __ Bind(&check_sequential);
+ STATIC_ASSERT(kSeqStringTag == 0);
+ __ TestAndBranchIfAnySet(result, kStringRepresentationMask, &external_string);
+
+ // Prepare sequential strings
+ STATIC_ASSERT(SeqTwoByteString::kHeaderSize == SeqOneByteString::kHeaderSize);
+ __ Add(string, string, SeqTwoByteString::kHeaderSize - kHeapObjectTag);
+ __ B(&check_encoding);
+
+ // Handle external strings.
+ __ Bind(&external_string);
+ if (FLAG_debug_code) {
+ // Assert that we do not have a cons or slice (indirect strings) here.
+ // Sequential strings have already been ruled out.
+ __ Tst(result, kIsIndirectStringMask);
+ __ Assert(eq, kExternalStringExpectedButNotFound);
+ }
+ // Rule out short external strings.
+ STATIC_CHECK(kShortExternalStringTag != 0);
+ // TestAndBranchIfAnySet can emit Tbnz. Do not use it because call_runtime
+ // can be bound far away in deferred code.
+ __ Tst(result, kShortExternalStringMask);
+ __ B(ne, call_runtime);
+ __ Ldr(string, FieldMemOperand(string, ExternalString::kResourceDataOffset));
+
+ Label ascii, done;
+ __ Bind(&check_encoding);
+ STATIC_ASSERT(kTwoByteStringTag == 0);
+ __ TestAndBranchIfAnySet(result, kStringEncodingMask, &ascii);
+ // Two-byte string.
+ __ Ldrh(result, MemOperand(string, index, LSL, 1));
+ __ B(&done);
+ __ Bind(&ascii);
+ // Ascii string.
+ __ Ldrb(result, MemOperand(string, index));
+ __ Bind(&done);
+}
+
+
+static MemOperand ExpConstant(Register base, int index) {
+ return MemOperand(base, index * kDoubleSize);
+}
+
+
+void MathExpGenerator::EmitMathExp(MacroAssembler* masm,
+ DoubleRegister input,
+ DoubleRegister result,
+ DoubleRegister double_temp1,
+ DoubleRegister double_temp2,
+ Register temp1,
+ Register temp2,
+ Register temp3) {
+ // TODO(jbramley): There are several instances where fnmsub could be used
+ // instead of fmul and fsub. Doing this changes the result, but since this is
+ // an estimation anyway, does it matter?
+
+ ASSERT(!AreAliased(input, result,
+ double_temp1, double_temp2,
+ temp1, temp2, temp3));
+ ASSERT(ExternalReference::math_exp_constants(0).address() != NULL);
+
+ Label done;
+ DoubleRegister double_temp3 = result;
+ Register constants = temp3;
+
+ // The algorithm used relies on some magic constants which are initialized in
+ // ExternalReference::InitializeMathExpData().
+
+ // Load the address of the start of the array.
+ __ Mov(constants, Operand(ExternalReference::math_exp_constants(0)));
+
+ // We have to do a four-way split here:
+ // - If input <= about -708.4, the output always rounds to zero.
+ // - If input >= about 709.8, the output always rounds to +infinity.
+ // - If the input is NaN, the output is NaN.
+ // - Otherwise, the result needs to be calculated.
+ Label result_is_finite_non_zero;
+ // Assert that we can load offset 0 (the small input threshold) and offset 1
+ // (the large input threshold) with a single ldp.
+ ASSERT(kDRegSizeInBytes == (ExpConstant(constants, 1).offset() -
+ ExpConstant(constants, 0).offset()));
+ __ Ldp(double_temp1, double_temp2, ExpConstant(constants, 0));
+
+ __ Fcmp(input, double_temp1);
+ __ Fccmp(input, double_temp2, NoFlag, hi);
+ // At this point, the condition flags can be in one of five states:
+ // NZCV
+ // 1000 -708.4 < input < 709.8 result = exp(input)
+ // 0110 input == 709.8 result = +infinity
+ // 0010 input > 709.8 result = +infinity
+ // 0011 input is NaN result = input
+ // 0000 input <= -708.4 result = +0.0
+
+ // Continue the common case first. 'mi' tests N == 1.
+ __ B(&result_is_finite_non_zero, mi);
+
+ // TODO(jbramley): Add (and use) a zero D register for A64.
+ // TODO(jbramley): Consider adding a +infinity register for A64.
+ __ Ldr(double_temp2, ExpConstant(constants, 2)); // Synthesize +infinity.
+ __ Fsub(double_temp1, double_temp1, double_temp1); // Synthesize +0.0.
+
+ // Select between +0.0 and +infinity. 'lo' tests C == 0.
+ __ Fcsel(result, double_temp1, double_temp2, lo);
+ // Select between {+0.0 or +infinity} and input. 'vc' tests V == 0.
+ __ Fcsel(result, result, input, vc);
+ __ B(&done);
+
+ // The rest is magic, as described in InitializeMathExpData().
+ __ Bind(&result_is_finite_non_zero);
+
+ // Assert that we can load offset 3 and offset 4 with a single ldp.
+ ASSERT(kDRegSizeInBytes == (ExpConstant(constants, 4).offset() -
+ ExpConstant(constants, 3).offset()));
+ __ Ldp(double_temp1, double_temp3, ExpConstant(constants, 3));
+ __ Fmadd(double_temp1, double_temp1, input, double_temp3);
+ __ Fmov(temp2.W(), double_temp1.S());
+ __ Fsub(double_temp1, double_temp1, double_temp3);
+
+ // Assert that we can load offset 5 and offset 6 with a single ldp.
+ ASSERT(kDRegSizeInBytes == (ExpConstant(constants, 6).offset() -
+ ExpConstant(constants, 5).offset()));
+ __ Ldp(double_temp2, double_temp3, ExpConstant(constants, 5));
+ // TODO(jbramley): Consider using Fnmsub here.
+ __ Fmul(double_temp1, double_temp1, double_temp2);
+ __ Fsub(double_temp1, double_temp1, input);
+
+ __ Fmul(double_temp2, double_temp1, double_temp1);
+ __ Fsub(double_temp3, double_temp3, double_temp1);
+ __ Fmul(double_temp3, double_temp3, double_temp2);
+
+ __ Mov(temp1.W(), Operand(temp2.W(), LSR, 11));
+
+ __ Ldr(double_temp2, ExpConstant(constants, 7));
+ // TODO(jbramley): Consider using Fnmsub here.
+ __ Fmul(double_temp3, double_temp3, double_temp2);
+ __ Fsub(double_temp3, double_temp3, double_temp1);
+
+ // The 8th constant is 1.0, so use an immediate move rather than a load.
+ // We can't generate a runtime assertion here as we would need to call Abort
+ // in the runtime and we don't have an Isolate when we generate this code.
+ __ Fmov(double_temp2, 1.0);
+ __ Fadd(double_temp3, double_temp3, double_temp2);
+
+ __ And(temp2, temp2, 0x7ff);
+ __ Add(temp1, temp1, 0x3ff);
+
+ // Do the final table lookup.
+ __ Mov(temp3, Operand(ExternalReference::math_exp_log_table()));
+
+ __ Add(temp3, temp3, Operand(temp2, LSL, kDRegSizeInBytesLog2));
+ __ Ldp(temp2.W(), temp3.W(), MemOperand(temp3));
+ __ Orr(temp1.W(), temp3.W(), Operand(temp1.W(), LSL, 20));
+ __ Bfi(temp2, temp1, 32, 32);
+ __ Fmov(double_temp1, temp2);
+
+ __ Fmul(result, double_temp3, double_temp1);
+
+ __ Bind(&done);
+}
+
+#undef __
+
+} } // namespace v8::internal
+
+#endif // V8_TARGET_ARCH_A64
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