Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 1 | // Copyright 2014 the V8 project authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 5 | #include "src/runtime/runtime-utils.h" |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 6 | |
| 7 | #include "src/arguments.h" |
| 8 | #include "src/assembler.h" |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 9 | #include "src/base/utils/random-number-generator.h" |
| 10 | #include "src/bootstrapper.h" |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 11 | #include "src/codegen.h" |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 12 | |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 13 | namespace v8 { |
| 14 | namespace internal { |
| 15 | |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 16 | RUNTIME_FUNCTION(Runtime_DoubleHi) { |
| 17 | HandleScope scope(isolate); |
| 18 | DCHECK(args.length() == 1); |
| 19 | CONVERT_DOUBLE_ARG_CHECKED(x, 0); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 20 | uint64_t unsigned64 = double_to_uint64(x); |
| 21 | uint32_t unsigned32 = static_cast<uint32_t>(unsigned64 >> 32); |
| 22 | int32_t signed32 = bit_cast<int32_t, uint32_t>(unsigned32); |
| 23 | return *isolate->factory()->NewNumber(signed32); |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 24 | } |
| 25 | |
| 26 | |
| 27 | RUNTIME_FUNCTION(Runtime_DoubleLo) { |
| 28 | HandleScope scope(isolate); |
| 29 | DCHECK(args.length() == 1); |
| 30 | CONVERT_DOUBLE_ARG_CHECKED(x, 0); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 31 | uint64_t unsigned64 = double_to_uint64(x); |
| 32 | uint32_t unsigned32 = static_cast<uint32_t>(unsigned64); |
| 33 | int32_t signed32 = bit_cast<int32_t, uint32_t>(unsigned32); |
| 34 | return *isolate->factory()->NewNumber(signed32); |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 35 | } |
| 36 | |
| 37 | |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 38 | // Slow version of Math.pow. We check for fast paths for special cases. |
| 39 | // Used if VFP3 is not available. |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 40 | RUNTIME_FUNCTION(Runtime_MathPow) { |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 41 | HandleScope scope(isolate); |
| 42 | DCHECK(args.length() == 2); |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 43 | isolate->counters()->math_pow_runtime()->Increment(); |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 44 | |
| 45 | CONVERT_DOUBLE_ARG_CHECKED(x, 0); |
| 46 | |
| 47 | // If the second argument is a smi, it is much faster to call the |
| 48 | // custom powi() function than the generic pow(). |
| 49 | if (args[1]->IsSmi()) { |
| 50 | int y = args.smi_at(1); |
| 51 | return *isolate->factory()->NewNumber(power_double_int(x, y)); |
| 52 | } |
| 53 | |
| 54 | CONVERT_DOUBLE_ARG_CHECKED(y, 1); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 55 | double result = power_helper(isolate, x, y); |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 56 | if (std::isnan(result)) return isolate->heap()->nan_value(); |
| 57 | return *isolate->factory()->NewNumber(result); |
| 58 | } |
| 59 | |
| 60 | |
| 61 | // Fast version of Math.pow if we know that y is not an integer and y is not |
| 62 | // -0.5 or 0.5. Used as slow case from full codegen. |
| 63 | RUNTIME_FUNCTION(Runtime_MathPowRT) { |
| 64 | HandleScope scope(isolate); |
| 65 | DCHECK(args.length() == 2); |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 66 | isolate->counters()->math_pow_runtime()->Increment(); |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 67 | |
| 68 | CONVERT_DOUBLE_ARG_CHECKED(x, 0); |
| 69 | CONVERT_DOUBLE_ARG_CHECKED(y, 1); |
| 70 | if (y == 0) { |
| 71 | return Smi::FromInt(1); |
| 72 | } else { |
| 73 | double result = power_double_double(x, y); |
| 74 | if (std::isnan(result)) return isolate->heap()->nan_value(); |
| 75 | return *isolate->factory()->NewNumber(result); |
| 76 | } |
| 77 | } |
| 78 | |
| 79 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 80 | RUNTIME_FUNCTION(Runtime_GenerateRandomNumbers) { |
| 81 | HandleScope scope(isolate); |
| 82 | DCHECK(args.length() == 1); |
Ben Murdoch | da12d29 | 2016-06-02 14:46:10 +0100 | [diff] [blame] | 83 | if (isolate->serializer_enabled()) { |
| 84 | // Random numbers in the snapshot are not really that random. And we cannot |
| 85 | // return a typed array as it cannot be serialized. To make calling |
| 86 | // Math.random possible when creating a custom startup snapshot, we simply |
| 87 | // return a normal array with a single random number. |
| 88 | Handle<HeapNumber> random_number = isolate->factory()->NewHeapNumber( |
| 89 | isolate->random_number_generator()->NextDouble()); |
| 90 | Handle<FixedArray> array_backing = isolate->factory()->NewFixedArray(1); |
| 91 | array_backing->set(0, *random_number); |
| 92 | return *isolate->factory()->NewJSArrayWithElements(array_backing); |
| 93 | } |
| 94 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 95 | static const int kState0Offset = 0; |
| 96 | static const int kState1Offset = 1; |
| 97 | static const int kRandomBatchSize = 64; |
| 98 | CONVERT_ARG_HANDLE_CHECKED(Object, maybe_typed_array, 0); |
| 99 | Handle<JSTypedArray> typed_array; |
| 100 | // Allocate typed array if it does not yet exist. |
| 101 | if (maybe_typed_array->IsJSTypedArray()) { |
| 102 | typed_array = Handle<JSTypedArray>::cast(maybe_typed_array); |
| 103 | } else { |
| 104 | static const int kByteLength = kRandomBatchSize * kDoubleSize; |
| 105 | Handle<JSArrayBuffer> buffer = |
| 106 | isolate->factory()->NewJSArrayBuffer(SharedFlag::kNotShared, TENURED); |
| 107 | JSArrayBuffer::SetupAllocatingData(buffer, isolate, kByteLength, true, |
| 108 | SharedFlag::kNotShared); |
| 109 | typed_array = isolate->factory()->NewJSTypedArray( |
| 110 | kExternalFloat64Array, buffer, 0, kRandomBatchSize); |
| 111 | } |
| 112 | |
| 113 | DisallowHeapAllocation no_gc; |
| 114 | double* array = |
| 115 | reinterpret_cast<double*>(typed_array->GetBuffer()->backing_store()); |
| 116 | // Fetch existing state. |
| 117 | uint64_t state0 = double_to_uint64(array[kState0Offset]); |
| 118 | uint64_t state1 = double_to_uint64(array[kState1Offset]); |
| 119 | // Initialize state if not yet initialized. |
| 120 | while (state0 == 0 || state1 == 0) { |
| 121 | isolate->random_number_generator()->NextBytes(&state0, sizeof(state0)); |
| 122 | isolate->random_number_generator()->NextBytes(&state1, sizeof(state1)); |
| 123 | } |
| 124 | // Create random numbers. |
| 125 | for (int i = kState1Offset + 1; i < kRandomBatchSize; i++) { |
| 126 | // Generate random numbers using xorshift128+. |
| 127 | base::RandomNumberGenerator::XorShift128(&state0, &state1); |
| 128 | array[i] = base::RandomNumberGenerator::ToDouble(state0, state1); |
| 129 | } |
| 130 | // Persist current state. |
| 131 | array[kState0Offset] = uint64_to_double(state0); |
| 132 | array[kState1Offset] = uint64_to_double(state1); |
| 133 | return *typed_array; |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 134 | } |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 135 | } // namespace internal |
| 136 | } // namespace v8 |