// Copyright 2013 the V8 project authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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#if V8_TARGET_ARCH_ARM64
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#include "src/arm64/utils-arm64.h"
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namespace v8 {
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namespace internal {
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#define __ assm->
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uint32_t float_sign(float val) {
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uint32_t bits = bit_cast<uint32_t>(val);
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return unsigned_bitextract_32(31, 31, bits);
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}
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uint32_t float_exp(float val) {
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uint32_t bits = bit_cast<uint32_t>(val);
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return unsigned_bitextract_32(30, 23, bits);
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}
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uint32_t float_mantissa(float val) {
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uint32_t bits = bit_cast<uint32_t>(val);
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return unsigned_bitextract_32(22, 0, bits);
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}
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uint32_t double_sign(double val) {
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uint64_t bits = bit_cast<uint64_t>(val);
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return static_cast<uint32_t>(unsigned_bitextract_64(63, 63, bits));
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}
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uint32_t double_exp(double val) {
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uint64_t bits = bit_cast<uint64_t>(val);
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return static_cast<uint32_t>(unsigned_bitextract_64(62, 52, bits));
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}
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uint64_t double_mantissa(double val) {
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uint64_t bits = bit_cast<uint64_t>(val);
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return unsigned_bitextract_64(51, 0, bits);
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}
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float float_pack(uint32_t sign, uint32_t exp, uint32_t mantissa) {
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uint32_t bits = sign << kFloatExponentBits | exp;
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return bit_cast<float>((bits << kFloatMantissaBits) | mantissa);
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}
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double double_pack(uint64_t sign, uint64_t exp, uint64_t mantissa) {
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uint64_t bits = sign << kDoubleExponentBits | exp;
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return bit_cast<double>((bits << kDoubleMantissaBits) | mantissa);
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}
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int float16classify(float16 value) {
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const uint16_t exponent_max = (1 << kFloat16ExponentBits) - 1;
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const uint16_t exponent_mask = exponent_max << kFloat16MantissaBits;
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const uint16_t mantissa_mask = (1 << kFloat16MantissaBits) - 1;
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const uint16_t exponent = (value & exponent_mask) >> kFloat16MantissaBits;
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const uint16_t mantissa = value & mantissa_mask;
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if (exponent == 0) {
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if (mantissa == 0) {
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return FP_ZERO;
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}
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return FP_SUBNORMAL;
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} else if (exponent == exponent_max) {
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if (mantissa == 0) {
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return FP_INFINITE;
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}
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return FP_NAN;
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}
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return FP_NORMAL;
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}
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int CountLeadingZeros(uint64_t value, int width) {
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DCHECK(base::bits::IsPowerOfTwo(width) && (width <= 64));
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if (value == 0) {
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return width;
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}
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return base::bits::CountLeadingZeros64(value << (64 - width));
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}
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int CountLeadingSignBits(int64_t value, int width) {
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DCHECK(base::bits::IsPowerOfTwo(width) && (width <= 64));
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if (value >= 0) {
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return CountLeadingZeros(value, width) - 1;
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} else {
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return CountLeadingZeros(~value, width) - 1;
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}
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}
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int CountTrailingZeros(uint64_t value, int width) {
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DCHECK((width == 32) || (width == 64));
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if (width == 64) {
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return static_cast<int>(base::bits::CountTrailingZeros64(value));
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}
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return static_cast<int>(base::bits::CountTrailingZeros32(
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static_cast<uint32_t>(value & 0xFFFFFFFFF)));
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}
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int CountSetBits(uint64_t value, int width) {
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DCHECK((width == 32) || (width == 64));
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if (width == 64) {
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return static_cast<int>(base::bits::CountPopulation(value));
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}
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return static_cast<int>(
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base::bits::CountPopulation(static_cast<uint32_t>(value & 0xFFFFFFFFF)));
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}
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int LowestSetBitPosition(uint64_t value) {
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DCHECK_NE(value, 0U);
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return CountTrailingZeros(value, 64) + 1;
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}
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int HighestSetBitPosition(uint64_t value) {
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DCHECK_NE(value, 0U);
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return 63 - CountLeadingZeros(value, 64);
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}
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uint64_t LargestPowerOf2Divisor(uint64_t value) {
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return value & -value;
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}
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int MaskToBit(uint64_t mask) {
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DCHECK_EQ(CountSetBits(mask, 64), 1);
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return CountTrailingZeros(mask, 64);
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}
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#undef __
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} // namespace internal
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} // namespace v8
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#endif // V8_TARGET_ARCH_ARM64
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