Upgrade V8 to 5.1.281.57 DO NOT MERGE
FPIIM-449
Change-Id: Id981b686b4d587ac31697662eb98bb34be42ad90
(cherry picked from commit 3b9bc31999c9787eb726ecdbfd5796bfdec32a18)
diff --git a/src/s390/codegen-s390.cc b/src/s390/codegen-s390.cc
new file mode 100644
index 0000000..6636a7c
--- /dev/null
+++ b/src/s390/codegen-s390.cc
@@ -0,0 +1,675 @@
+// Copyright 2015 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "src/s390/codegen-s390.h"
+
+#if V8_TARGET_ARCH_S390
+
+#include "src/codegen.h"
+#include "src/macro-assembler.h"
+#include "src/s390/simulator-s390.h"
+
+namespace v8 {
+namespace internal {
+
+#define __ masm.
+
+#if defined(USE_SIMULATOR)
+byte* fast_exp_s390_machine_code = nullptr;
+double fast_exp_simulator(double x, Isolate* isolate) {
+ return Simulator::current(isolate)->CallFPReturnsDouble(
+ fast_exp_s390_machine_code, x, 0);
+}
+#endif
+
+UnaryMathFunctionWithIsolate CreateExpFunction(Isolate* isolate) {
+ size_t actual_size;
+ byte* buffer =
+ static_cast<byte*>(base::OS::Allocate(1 * KB, &actual_size, true));
+ if (buffer == nullptr) return nullptr;
+ ExternalReference::InitializeMathExpData();
+
+ MacroAssembler masm(isolate, buffer, static_cast<int>(actual_size),
+ CodeObjectRequired::kNo);
+
+ {
+ DoubleRegister input = d0;
+ DoubleRegister result = d2;
+ DoubleRegister double_scratch1 = d3;
+ DoubleRegister double_scratch2 = d4;
+ Register temp1 = r6;
+ Register temp2 = r7;
+ Register temp3 = r8;
+
+ __ Push(temp3, temp2, temp1);
+ MathExpGenerator::EmitMathExp(&masm, input, result, double_scratch1,
+ double_scratch2, temp1, temp2, temp3);
+ __ Pop(temp3, temp2, temp1);
+ __ ldr(d0, result);
+ __ Ret();
+ }
+
+ CodeDesc desc;
+ masm.GetCode(&desc);
+ DCHECK(ABI_USES_FUNCTION_DESCRIPTORS || !RelocInfo::RequiresRelocation(desc));
+
+ Assembler::FlushICache(isolate, buffer, actual_size);
+ base::OS::ProtectCode(buffer, actual_size);
+
+#if !defined(USE_SIMULATOR)
+ return FUNCTION_CAST<UnaryMathFunctionWithIsolate>(buffer);
+#else
+ fast_exp_s390_machine_code = buffer;
+ return &fast_exp_simulator;
+#endif
+}
+
+UnaryMathFunctionWithIsolate CreateSqrtFunction(Isolate* isolate) {
+#if defined(USE_SIMULATOR)
+ return nullptr;
+#else
+ size_t actual_size;
+ byte* buffer =
+ static_cast<byte*>(base::OS::Allocate(1 * KB, &actual_size, true));
+ if (buffer == nullptr) return nullptr;
+
+ MacroAssembler masm(isolate, buffer, static_cast<int>(actual_size),
+ CodeObjectRequired::kNo);
+
+ __ MovFromFloatParameter(d0);
+ __ sqdbr(d0, d0);
+ __ MovToFloatResult(d0);
+ __ Ret();
+
+ CodeDesc desc;
+ masm.GetCode(&desc);
+ DCHECK(ABI_USES_FUNCTION_DESCRIPTORS || !RelocInfo::RequiresRelocation(desc));
+
+ Assembler::FlushICache(isolate, buffer, actual_size);
+ base::OS::ProtectCode(buffer, actual_size);
+ return FUNCTION_CAST<UnaryMathFunctionWithIsolate>(buffer);
+#endif
+}
+
+#undef __
+
+// -------------------------------------------------------------------------
+// Platform-specific RuntimeCallHelper functions.
+
+void StubRuntimeCallHelper::BeforeCall(MacroAssembler* masm) const {
+ masm->EnterFrame(StackFrame::INTERNAL);
+ DCHECK(!masm->has_frame());
+ masm->set_has_frame(true);
+}
+
+void StubRuntimeCallHelper::AfterCall(MacroAssembler* masm) const {
+ masm->LeaveFrame(StackFrame::INTERNAL);
+ DCHECK(masm->has_frame());
+ masm->set_has_frame(false);
+}
+
+// -------------------------------------------------------------------------
+// Code generators
+
+#define __ ACCESS_MASM(masm)
+
+void ElementsTransitionGenerator::GenerateMapChangeElementsTransition(
+ MacroAssembler* masm, Register receiver, Register key, Register value,
+ Register target_map, AllocationSiteMode mode,
+ Label* allocation_memento_found) {
+ Register scratch_elements = r6;
+ DCHECK(!AreAliased(receiver, key, value, target_map, scratch_elements));
+
+ if (mode == TRACK_ALLOCATION_SITE) {
+ DCHECK(allocation_memento_found != NULL);
+ __ JumpIfJSArrayHasAllocationMemento(receiver, scratch_elements, r1,
+ allocation_memento_found);
+ }
+
+ // Set transitioned map.
+ __ StoreP(target_map, FieldMemOperand(receiver, HeapObject::kMapOffset));
+ __ RecordWriteField(receiver, HeapObject::kMapOffset, target_map, r1,
+ kLRHasNotBeenSaved, kDontSaveFPRegs, EMIT_REMEMBERED_SET,
+ OMIT_SMI_CHECK);
+}
+
+void ElementsTransitionGenerator::GenerateSmiToDouble(
+ MacroAssembler* masm, Register receiver, Register key, Register value,
+ Register target_map, AllocationSiteMode mode, Label* fail) {
+ // lr contains the return address
+ Label loop, entry, convert_hole, gc_required, only_change_map, done;
+ Register elements = r6;
+ Register length = r7;
+ Register array = r8;
+ Register array_end = array;
+
+ // target_map parameter can be clobbered.
+ Register scratch1 = target_map;
+ Register scratch2 = r1;
+
+ // Verify input registers don't conflict with locals.
+ DCHECK(!AreAliased(receiver, key, value, target_map, elements, length, array,
+ scratch2));
+
+ if (mode == TRACK_ALLOCATION_SITE) {
+ __ JumpIfJSArrayHasAllocationMemento(receiver, elements, scratch2, fail);
+ }
+
+ // Check for empty arrays, which only require a map transition and no changes
+ // to the backing store.
+ __ LoadP(elements, FieldMemOperand(receiver, JSObject::kElementsOffset));
+ __ CompareRoot(elements, Heap::kEmptyFixedArrayRootIndex);
+ __ beq(&only_change_map, Label::kNear);
+
+ // Preserve lr and use r14 as a temporary register.
+ __ push(r14);
+
+ __ LoadP(length, FieldMemOperand(elements, FixedArray::kLengthOffset));
+ // length: number of elements (smi-tagged)
+
+ // Allocate new FixedDoubleArray.
+ __ SmiToDoubleArrayOffset(r14, length);
+ __ AddP(r14, Operand(FixedDoubleArray::kHeaderSize));
+ __ Allocate(r14, array, r9, scratch2, &gc_required, DOUBLE_ALIGNMENT);
+
+ // Set destination FixedDoubleArray's length and map.
+ __ LoadRoot(scratch2, Heap::kFixedDoubleArrayMapRootIndex);
+ __ StoreP(length, MemOperand(array, FixedDoubleArray::kLengthOffset));
+ // Update receiver's map.
+ __ StoreP(scratch2, MemOperand(array, HeapObject::kMapOffset));
+
+ __ StoreP(target_map, FieldMemOperand(receiver, HeapObject::kMapOffset));
+ __ RecordWriteField(receiver, HeapObject::kMapOffset, target_map, scratch2,
+ kLRHasBeenSaved, kDontSaveFPRegs, OMIT_REMEMBERED_SET,
+ OMIT_SMI_CHECK);
+ // Replace receiver's backing store with newly created FixedDoubleArray.
+ __ AddP(scratch1, array, Operand(kHeapObjectTag));
+ __ StoreP(scratch1, FieldMemOperand(receiver, JSObject::kElementsOffset));
+ __ RecordWriteField(receiver, JSObject::kElementsOffset, scratch1, scratch2,
+ kLRHasBeenSaved, kDontSaveFPRegs, EMIT_REMEMBERED_SET,
+ OMIT_SMI_CHECK);
+
+ // Prepare for conversion loop.
+ __ AddP(target_map, elements,
+ Operand(FixedArray::kHeaderSize - kHeapObjectTag));
+ __ AddP(r9, array, Operand(FixedDoubleArray::kHeaderSize));
+ __ SmiToDoubleArrayOffset(array, length);
+ __ AddP(array_end, r9, array);
+// Repurpose registers no longer in use.
+#if V8_TARGET_ARCH_S390X
+ Register hole_int64 = elements;
+#else
+ Register hole_lower = elements;
+ Register hole_upper = length;
+#endif
+ // scratch1: begin of source FixedArray element fields, not tagged
+ // hole_lower: kHoleNanLower32 OR hol_int64
+ // hole_upper: kHoleNanUpper32
+ // array_end: end of destination FixedDoubleArray, not tagged
+ // scratch2: begin of FixedDoubleArray element fields, not tagged
+
+ __ b(&entry, Label::kNear);
+
+ __ bind(&only_change_map);
+ __ StoreP(target_map, FieldMemOperand(receiver, HeapObject::kMapOffset));
+ __ RecordWriteField(receiver, HeapObject::kMapOffset, target_map, scratch2,
+ kLRHasNotBeenSaved, kDontSaveFPRegs, OMIT_REMEMBERED_SET,
+ OMIT_SMI_CHECK);
+ __ b(&done, Label::kNear);
+
+ // Call into runtime if GC is required.
+ __ bind(&gc_required);
+ __ pop(r14);
+ __ b(fail);
+
+ // Convert and copy elements.
+ __ bind(&loop);
+ __ LoadP(r14, MemOperand(scratch1));
+ __ la(scratch1, MemOperand(scratch1, kPointerSize));
+ // r1: current element
+ __ UntagAndJumpIfNotSmi(r14, r14, &convert_hole);
+
+ // Normal smi, convert to double and store.
+ __ ConvertIntToDouble(r14, d0);
+ __ StoreDouble(d0, MemOperand(r9, 0));
+ __ la(r9, MemOperand(r9, 8));
+
+ __ b(&entry, Label::kNear);
+
+ // Hole found, store the-hole NaN.
+ __ bind(&convert_hole);
+ if (FLAG_debug_code) {
+ // Restore a "smi-untagged" heap object.
+ __ LoadP(r1, MemOperand(r5, -kPointerSize));
+ __ CompareRoot(r1, Heap::kTheHoleValueRootIndex);
+ __ Assert(eq, kObjectFoundInSmiOnlyArray);
+ }
+#if V8_TARGET_ARCH_S390X
+ __ stg(hole_int64, MemOperand(r9, 0));
+#else
+ __ StoreW(hole_upper, MemOperand(r9, Register::kExponentOffset));
+ __ StoreW(hole_lower, MemOperand(r9, Register::kMantissaOffset));
+#endif
+ __ AddP(r9, Operand(8));
+
+ __ bind(&entry);
+ __ CmpP(r9, array_end);
+ __ blt(&loop);
+
+ __ pop(r14);
+ __ bind(&done);
+}
+
+void ElementsTransitionGenerator::GenerateDoubleToObject(
+ MacroAssembler* masm, Register receiver, Register key, Register value,
+ Register target_map, AllocationSiteMode mode, Label* fail) {
+ // Register lr contains the return address.
+ Label loop, convert_hole, gc_required, only_change_map;
+ Register elements = r6;
+ Register array = r8;
+ Register length = r7;
+ Register scratch = r1;
+ Register scratch3 = r9;
+ Register hole_value = r9;
+
+ // Verify input registers don't conflict with locals.
+ DCHECK(!AreAliased(receiver, key, value, target_map, elements, array, length,
+ scratch));
+
+ if (mode == TRACK_ALLOCATION_SITE) {
+ __ JumpIfJSArrayHasAllocationMemento(receiver, elements, scratch3, fail);
+ }
+
+ // Check for empty arrays, which only require a map transition and no changes
+ // to the backing store.
+ __ LoadP(elements, FieldMemOperand(receiver, JSObject::kElementsOffset));
+ __ CompareRoot(elements, Heap::kEmptyFixedArrayRootIndex);
+ __ beq(&only_change_map);
+
+ __ Push(target_map, receiver, key, value);
+ __ LoadP(length, FieldMemOperand(elements, FixedArray::kLengthOffset));
+ // elements: source FixedDoubleArray
+ // length: number of elements (smi-tagged)
+
+ // Allocate new FixedArray.
+ // Re-use value and target_map registers, as they have been saved on the
+ // stack.
+ Register array_size = value;
+ Register allocate_scratch = target_map;
+ __ LoadImmP(array_size, Operand(FixedDoubleArray::kHeaderSize));
+ __ SmiToPtrArrayOffset(r0, length);
+ __ AddP(array_size, r0);
+ __ Allocate(array_size, array, allocate_scratch, scratch, &gc_required,
+ NO_ALLOCATION_FLAGS);
+ // array: destination FixedArray, not tagged as heap object
+ // Set destination FixedDoubleArray's length and map.
+ __ LoadRoot(scratch, Heap::kFixedArrayMapRootIndex);
+ __ StoreP(length, MemOperand(array, FixedDoubleArray::kLengthOffset));
+ __ StoreP(scratch, MemOperand(array, HeapObject::kMapOffset));
+ __ AddP(array, Operand(kHeapObjectTag));
+
+ // Prepare for conversion loop.
+ Register src_elements = elements;
+ Register dst_elements = target_map;
+ Register dst_end = length;
+ Register heap_number_map = scratch;
+ __ AddP(src_elements,
+ Operand(FixedDoubleArray::kHeaderSize - kHeapObjectTag));
+ __ SmiToPtrArrayOffset(length, length);
+ __ LoadRoot(hole_value, Heap::kTheHoleValueRootIndex);
+
+ Label initialization_loop, loop_done;
+ __ ShiftRightP(scratch, length, Operand(kPointerSizeLog2));
+ __ beq(&loop_done, Label::kNear);
+
+ // Allocating heap numbers in the loop below can fail and cause a jump to
+ // gc_required. We can't leave a partly initialized FixedArray behind,
+ // so pessimistically fill it with holes now.
+ __ AddP(dst_elements, array,
+ Operand(FixedArray::kHeaderSize - kHeapObjectTag - kPointerSize));
+ __ bind(&initialization_loop);
+ __ StoreP(hole_value, MemOperand(dst_elements, kPointerSize));
+ __ lay(dst_elements, MemOperand(dst_elements, kPointerSize));
+ __ BranchOnCount(scratch, &initialization_loop);
+
+ __ AddP(dst_elements, array,
+ Operand(FixedArray::kHeaderSize - kHeapObjectTag));
+ __ AddP(dst_end, dst_elements, length);
+ __ LoadRoot(heap_number_map, Heap::kHeapNumberMapRootIndex);
+ // Using offsetted addresses in src_elements to fully take advantage of
+ // post-indexing.
+ // dst_elements: begin of destination FixedArray element fields, not tagged
+ // src_elements: begin of source FixedDoubleArray element fields,
+ // not tagged, +4
+ // dst_end: end of destination FixedArray, not tagged
+ // array: destination FixedArray
+ // hole_value: the-hole pointer
+ // heap_number_map: heap number map
+ __ b(&loop, Label::kNear);
+
+ // Call into runtime if GC is required.
+ __ bind(&gc_required);
+ __ Pop(target_map, receiver, key, value);
+ __ b(fail);
+
+ // Replace the-hole NaN with the-hole pointer.
+ __ bind(&convert_hole);
+ __ StoreP(hole_value, MemOperand(dst_elements));
+ __ AddP(dst_elements, Operand(kPointerSize));
+ __ CmpLogicalP(dst_elements, dst_end);
+ __ bge(&loop_done);
+
+ __ bind(&loop);
+ Register upper_bits = key;
+ __ LoadlW(upper_bits, MemOperand(src_elements, Register::kExponentOffset));
+ __ AddP(src_elements, Operand(kDoubleSize));
+ // upper_bits: current element's upper 32 bit
+ // src_elements: address of next element's upper 32 bit
+ __ Cmp32(upper_bits, Operand(kHoleNanUpper32));
+ __ beq(&convert_hole, Label::kNear);
+
+ // Non-hole double, copy value into a heap number.
+ Register heap_number = receiver;
+ Register scratch2 = value;
+ __ AllocateHeapNumber(heap_number, scratch2, scratch3, heap_number_map,
+ &gc_required);
+// heap_number: new heap number
+#if V8_TARGET_ARCH_S390X
+ __ lg(scratch2, MemOperand(src_elements, -kDoubleSize));
+ // subtract tag for std
+ __ AddP(upper_bits, heap_number, Operand(-kHeapObjectTag));
+ __ stg(scratch2, MemOperand(upper_bits, HeapNumber::kValueOffset));
+#else
+ __ LoadlW(scratch2,
+ MemOperand(src_elements, Register::kMantissaOffset - kDoubleSize));
+ __ LoadlW(upper_bits,
+ MemOperand(src_elements, Register::kExponentOffset - kDoubleSize));
+ __ StoreW(scratch2,
+ FieldMemOperand(heap_number, HeapNumber::kMantissaOffset));
+ __ StoreW(upper_bits,
+ FieldMemOperand(heap_number, HeapNumber::kExponentOffset));
+#endif
+ __ LoadRR(scratch2, dst_elements);
+ __ StoreP(heap_number, MemOperand(dst_elements));
+ __ AddP(dst_elements, Operand(kPointerSize));
+ __ RecordWrite(array, scratch2, heap_number, kLRHasNotBeenSaved,
+ kDontSaveFPRegs, EMIT_REMEMBERED_SET, OMIT_SMI_CHECK);
+ __ CmpLogicalP(dst_elements, dst_end);
+ __ blt(&loop);
+ __ bind(&loop_done);
+
+ __ Pop(target_map, receiver, key, value);
+ // Replace receiver's backing store with newly created and filled FixedArray.
+ __ StoreP(array, FieldMemOperand(receiver, JSObject::kElementsOffset));
+ __ RecordWriteField(receiver, JSObject::kElementsOffset, array, scratch,
+ kLRHasNotBeenSaved, kDontSaveFPRegs, EMIT_REMEMBERED_SET,
+ OMIT_SMI_CHECK);
+
+ __ bind(&only_change_map);
+ // Update receiver's map.
+ __ StoreP(target_map, FieldMemOperand(receiver, HeapObject::kMapOffset));
+ __ RecordWriteField(receiver, HeapObject::kMapOffset, target_map, scratch,
+ kLRHasNotBeenSaved, kDontSaveFPRegs, OMIT_REMEMBERED_SET,
+ OMIT_SMI_CHECK);
+}
+
+// assume ip can be used as a scratch register below
+void StringCharLoadGenerator::Generate(MacroAssembler* masm, Register string,
+ Register index, Register result,
+ Label* call_runtime) {
+ // Fetch the instance type of the receiver into result register.
+ __ LoadP(result, FieldMemOperand(string, HeapObject::kMapOffset));
+ __ LoadlB(result, FieldMemOperand(result, Map::kInstanceTypeOffset));
+
+ // We need special handling for indirect strings.
+ Label check_sequential;
+ __ mov(r0, Operand(kIsIndirectStringMask));
+ __ AndP(r0, result);
+ __ beq(&check_sequential, Label::kNear /*, cr0*/);
+
+ // Dispatch on the indirect string shape: slice or cons.
+ Label cons_string;
+ __ mov(ip, Operand(kSlicedNotConsMask));
+ __ LoadRR(r0, result);
+ __ AndP(r0, ip /*, SetRC*/); // Should be okay to remove RC
+ __ beq(&cons_string, Label::kNear /*, cr0*/);
+
+ // Handle slices.
+ Label indirect_string_loaded;
+ __ LoadP(result, FieldMemOperand(string, SlicedString::kOffsetOffset));
+ __ LoadP(string, FieldMemOperand(string, SlicedString::kParentOffset));
+ __ SmiUntag(ip, result);
+ __ AddP(index, ip);
+ __ b(&indirect_string_loaded, Label::kNear);
+
+ // 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);
+ __ LoadP(result, FieldMemOperand(string, ConsString::kSecondOffset));
+ __ CompareRoot(result, Heap::kempty_stringRootIndex);
+ __ bne(call_runtime);
+ // Get the first of the two strings and load its instance type.
+ __ LoadP(string, FieldMemOperand(string, ConsString::kFirstOffset));
+
+ __ bind(&indirect_string_loaded);
+ __ LoadP(result, FieldMemOperand(string, HeapObject::kMapOffset));
+ __ LoadlB(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);
+ __ mov(r0, Operand(kStringRepresentationMask));
+ __ AndP(r0, result);
+ __ bne(&external_string, Label::kNear);
+
+ // Prepare sequential strings
+ STATIC_ASSERT(SeqTwoByteString::kHeaderSize == SeqOneByteString::kHeaderSize);
+ __ AddP(string, Operand(SeqTwoByteString::kHeaderSize - kHeapObjectTag));
+ __ b(&check_encoding, Label::kNear);
+
+ // 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.
+ __ mov(r0, Operand(kIsIndirectStringMask));
+ __ AndP(r0, result);
+ __ Assert(eq, kExternalStringExpectedButNotFound, cr0);
+ }
+ // Rule out short external strings.
+ STATIC_ASSERT(kShortExternalStringTag != 0);
+ __ mov(r0, Operand(kShortExternalStringMask));
+ __ AndP(r0, result);
+ __ bne(call_runtime /*, cr0*/);
+ __ LoadP(string,
+ FieldMemOperand(string, ExternalString::kResourceDataOffset));
+
+ Label one_byte, done;
+ __ bind(&check_encoding);
+ STATIC_ASSERT(kTwoByteStringTag == 0);
+ __ mov(r0, Operand(kStringEncodingMask));
+ __ AndP(r0, result);
+ __ bne(&one_byte, Label::kNear);
+ // Two-byte string.
+ __ ShiftLeftP(result, index, Operand(1));
+ __ LoadLogicalHalfWordP(result, MemOperand(string, result));
+ __ b(&done, Label::kNear);
+ __ bind(&one_byte);
+ // One-byte string.
+ __ LoadlB(result, MemOperand(string, index));
+ __ bind(&done);
+}
+
+static MemOperand ExpConstant(int index, Register base) {
+ return MemOperand(base, index * kDoubleSize);
+}
+
+void MathExpGenerator::EmitMathExp(MacroAssembler* masm, DoubleRegister input,
+ DoubleRegister result,
+ DoubleRegister double_scratch1,
+ DoubleRegister double_scratch2,
+ Register temp1, Register temp2,
+ Register temp3) {
+ DCHECK(!input.is(result));
+ DCHECK(!input.is(double_scratch1));
+ DCHECK(!input.is(double_scratch2));
+ DCHECK(!result.is(double_scratch1));
+ DCHECK(!result.is(double_scratch2));
+ DCHECK(!double_scratch1.is(double_scratch2));
+ DCHECK(!temp1.is(temp2));
+ DCHECK(!temp1.is(temp3));
+ DCHECK(!temp2.is(temp3));
+ DCHECK(ExternalReference::math_exp_constants(0).address() != NULL);
+ DCHECK(!masm->serializer_enabled()); // External references not serializable.
+
+ Label zero, infinity, done;
+
+ __ mov(temp3, Operand(ExternalReference::math_exp_constants(0)));
+
+ __ LoadDouble(double_scratch1, ExpConstant(0, temp3));
+ __ cdbr(double_scratch1, input);
+ __ ldr(result, input);
+ __ bunordered(&done, Label::kNear);
+ __ bge(&zero, Label::kNear);
+
+ __ LoadDouble(double_scratch2, ExpConstant(1, temp3));
+ __ cdbr(input, double_scratch2);
+ __ bge(&infinity, Label::kNear);
+
+ __ LoadDouble(double_scratch1, ExpConstant(3, temp3));
+ __ LoadDouble(result, ExpConstant(4, temp3));
+
+ // Do not generate madbr, as intermediate result are not
+ // rounded properly
+ __ mdbr(double_scratch1, input);
+ __ adbr(double_scratch1, result);
+
+ // Move low word of double_scratch1 to temp2
+ __ lgdr(temp2, double_scratch1);
+ __ nihf(temp2, Operand::Zero());
+
+ __ sdbr(double_scratch1, result);
+ __ LoadDouble(result, ExpConstant(6, temp3));
+ __ LoadDouble(double_scratch2, ExpConstant(5, temp3));
+ __ mdbr(double_scratch1, double_scratch2);
+ __ sdbr(double_scratch1, input);
+ __ sdbr(result, double_scratch1);
+ __ ldr(double_scratch2, double_scratch1);
+ __ mdbr(double_scratch2, double_scratch2);
+ __ mdbr(result, double_scratch2);
+ __ LoadDouble(double_scratch2, ExpConstant(7, temp3));
+ __ mdbr(result, double_scratch2);
+ __ sdbr(result, double_scratch1);
+ __ LoadDouble(double_scratch2, ExpConstant(8, temp3));
+ __ adbr(result, double_scratch2);
+ __ ShiftRight(temp1, temp2, Operand(11));
+ __ AndP(temp2, Operand(0x7ff));
+ __ AddP(temp1, Operand(0x3ff));
+
+ // Must not call ExpConstant() after overwriting temp3!
+ __ mov(temp3, Operand(ExternalReference::math_exp_log_table()));
+ __ ShiftLeft(temp2, temp2, Operand(3));
+
+ __ lg(temp2, MemOperand(temp2, temp3));
+ __ sllg(temp1, temp1, Operand(52));
+ __ ogr(temp2, temp1);
+ __ ldgr(double_scratch1, temp2);
+
+ __ mdbr(result, double_scratch1);
+ __ b(&done, Label::kNear);
+
+ __ bind(&zero);
+ __ lzdr(kDoubleRegZero);
+ __ ldr(result, kDoubleRegZero);
+ __ b(&done, Label::kNear);
+
+ __ bind(&infinity);
+ __ LoadDouble(result, ExpConstant(2, temp3));
+
+ __ bind(&done);
+}
+
+#undef __
+
+CodeAgingHelper::CodeAgingHelper(Isolate* isolate) {
+ USE(isolate);
+ DCHECK(young_sequence_.length() == kNoCodeAgeSequenceLength);
+ // Since patcher is a large object, allocate it dynamically when needed,
+ // to avoid overloading the stack in stress conditions.
+ // DONT_FLUSH is used because the CodeAgingHelper is initialized early in
+ // the process, before ARM simulator ICache is setup.
+ base::SmartPointer<CodePatcher> patcher(
+ new CodePatcher(isolate, young_sequence_.start(),
+ young_sequence_.length(), CodePatcher::DONT_FLUSH));
+ PredictableCodeSizeScope scope(patcher->masm(), young_sequence_.length());
+ patcher->masm()->PushStandardFrame(r3);
+}
+
+#ifdef DEBUG
+bool CodeAgingHelper::IsOld(byte* candidate) const {
+ return Assembler::IsNop(Assembler::instr_at(candidate));
+}
+#endif
+
+bool Code::IsYoungSequence(Isolate* isolate, byte* sequence) {
+ bool result = isolate->code_aging_helper()->IsYoung(sequence);
+ DCHECK(result || isolate->code_aging_helper()->IsOld(sequence));
+ return result;
+}
+
+void Code::GetCodeAgeAndParity(Isolate* isolate, byte* sequence, Age* age,
+ MarkingParity* parity) {
+ if (IsYoungSequence(isolate, sequence)) {
+ *age = kNoAgeCodeAge;
+ *parity = NO_MARKING_PARITY;
+ } else {
+ Code* code = NULL;
+ Address target_address =
+ Assembler::target_address_at(sequence + kCodeAgingTargetDelta, code);
+ Code* stub = GetCodeFromTargetAddress(target_address);
+ GetCodeAgeAndParity(stub, age, parity);
+ }
+}
+
+void Code::PatchPlatformCodeAge(Isolate* isolate, byte* sequence, Code::Age age,
+ MarkingParity parity) {
+ uint32_t young_length = isolate->code_aging_helper()->young_sequence_length();
+ if (age == kNoAgeCodeAge) {
+ isolate->code_aging_helper()->CopyYoungSequenceTo(sequence);
+ Assembler::FlushICache(isolate, sequence, young_length);
+ } else {
+ // FIXED_SEQUENCE
+ Code* stub = GetCodeAgeStub(isolate, age, parity);
+ CodePatcher patcher(isolate, sequence, young_length);
+ intptr_t target = reinterpret_cast<intptr_t>(stub->instruction_start());
+ // We need to push lr on stack so that GenerateMakeCodeYoungAgainCommon
+ // knows where to pick up the return address
+ //
+ // Since we can no longer guarentee ip will hold the branch address
+ // because of BRASL, use Call so that GenerateMakeCodeYoungAgainCommon
+ // can calculate the branch address offset
+ patcher.masm()->nop(); // marker to detect sequence (see IsOld)
+ patcher.masm()->CleanseP(r14);
+ patcher.masm()->Push(r14);
+ patcher.masm()->mov(r2, Operand(target));
+ patcher.masm()->Call(r2);
+ for (int i = 0; i < kNoCodeAgeSequenceLength - kCodeAgingSequenceLength;
+ i += 2) {
+ // TODO(joransiu): Create nop function to pad
+ // (kNoCodeAgeSequenceLength - kCodeAgingSequenceLength) bytes.
+ patcher.masm()->nop(); // 2-byte nops().
+ }
+ }
+}
+
+} // namespace internal
+} // namespace v8
+
+#endif // V8_TARGET_ARCH_S390