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Diffstat (limited to 'qemu/disas/libvixl/vixl/utils.h')
-rw-r--r-- | qemu/disas/libvixl/vixl/utils.h | 286 |
1 files changed, 286 insertions, 0 deletions
diff --git a/qemu/disas/libvixl/vixl/utils.h b/qemu/disas/libvixl/vixl/utils.h new file mode 100644 index 000000000..5ab134e24 --- /dev/null +++ b/qemu/disas/libvixl/vixl/utils.h @@ -0,0 +1,286 @@ +// Copyright 2015, ARM Limited +// 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 ARM Limited 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 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. + +#ifndef VIXL_UTILS_H +#define VIXL_UTILS_H + +#include <string.h> +#include <cmath> +#include "vixl/globals.h" +#include "vixl/compiler-intrinsics.h" + +namespace vixl { + +// Macros for compile-time format checking. +#if GCC_VERSION_OR_NEWER(4, 4, 0) +#define PRINTF_CHECK(format_index, varargs_index) \ + __attribute__((format(gnu_printf, format_index, varargs_index))) +#else +#define PRINTF_CHECK(format_index, varargs_index) +#endif + +// Check number width. +inline bool is_intn(unsigned n, int64_t x) { + VIXL_ASSERT((0 < n) && (n < 64)); + int64_t limit = INT64_C(1) << (n - 1); + return (-limit <= x) && (x < limit); +} + +inline bool is_uintn(unsigned n, int64_t x) { + VIXL_ASSERT((0 < n) && (n < 64)); + return !(x >> n); +} + +inline uint32_t truncate_to_intn(unsigned n, int64_t x) { + VIXL_ASSERT((0 < n) && (n < 64)); + return static_cast<uint32_t>(x & ((INT64_C(1) << n) - 1)); +} + +#define INT_1_TO_63_LIST(V) \ +V(1) V(2) V(3) V(4) V(5) V(6) V(7) V(8) \ +V(9) V(10) V(11) V(12) V(13) V(14) V(15) V(16) \ +V(17) V(18) V(19) V(20) V(21) V(22) V(23) V(24) \ +V(25) V(26) V(27) V(28) V(29) V(30) V(31) V(32) \ +V(33) V(34) V(35) V(36) V(37) V(38) V(39) V(40) \ +V(41) V(42) V(43) V(44) V(45) V(46) V(47) V(48) \ +V(49) V(50) V(51) V(52) V(53) V(54) V(55) V(56) \ +V(57) V(58) V(59) V(60) V(61) V(62) V(63) + +#define DECLARE_IS_INT_N(N) \ +inline bool is_int##N(int64_t x) { return is_intn(N, x); } +#define DECLARE_IS_UINT_N(N) \ +inline bool is_uint##N(int64_t x) { return is_uintn(N, x); } +#define DECLARE_TRUNCATE_TO_INT_N(N) \ +inline uint32_t truncate_to_int##N(int x) { return truncate_to_intn(N, x); } +INT_1_TO_63_LIST(DECLARE_IS_INT_N) +INT_1_TO_63_LIST(DECLARE_IS_UINT_N) +INT_1_TO_63_LIST(DECLARE_TRUNCATE_TO_INT_N) +#undef DECLARE_IS_INT_N +#undef DECLARE_IS_UINT_N +#undef DECLARE_TRUNCATE_TO_INT_N + +// Bit field extraction. +inline uint32_t unsigned_bitextract_32(int msb, int lsb, uint32_t x) { + return (x >> lsb) & ((1 << (1 + msb - lsb)) - 1); +} + +inline uint64_t unsigned_bitextract_64(int msb, int lsb, uint64_t x) { + return (x >> lsb) & ((static_cast<uint64_t>(1) << (1 + msb - lsb)) - 1); +} + +inline int32_t signed_bitextract_32(int msb, int lsb, int32_t x) { + return (x << (31 - msb)) >> (lsb + 31 - msb); +} + +inline int64_t signed_bitextract_64(int msb, int lsb, int64_t x) { + return (x << (63 - msb)) >> (lsb + 63 - msb); +} + +// Floating point representation. +uint32_t float_to_rawbits(float value); +uint64_t double_to_rawbits(double value); +float rawbits_to_float(uint32_t bits); +double rawbits_to_double(uint64_t bits); + +uint32_t float_sign(float val); +uint32_t float_exp(float val); +uint32_t float_mantissa(float val); +uint32_t double_sign(double val); +uint32_t double_exp(double val); +uint64_t double_mantissa(double val); + +float float_pack(uint32_t sign, uint32_t exp, uint32_t mantissa); +double double_pack(uint64_t sign, uint64_t exp, uint64_t mantissa); + +// An fpclassify() function for 16-bit half-precision floats. +int float16classify(float16 value); + +// NaN tests. +inline bool IsSignallingNaN(double num) { + const uint64_t kFP64QuietNaNMask = UINT64_C(0x0008000000000000); + uint64_t raw = double_to_rawbits(num); + if (std::isnan(num) && ((raw & kFP64QuietNaNMask) == 0)) { + return true; + } + return false; +} + + +inline bool IsSignallingNaN(float num) { + const uint32_t kFP32QuietNaNMask = 0x00400000; + uint32_t raw = float_to_rawbits(num); + if (std::isnan(num) && ((raw & kFP32QuietNaNMask) == 0)) { + return true; + } + return false; +} + + +inline bool IsSignallingNaN(float16 num) { + const uint16_t kFP16QuietNaNMask = 0x0200; + return (float16classify(num) == FP_NAN) && + ((num & kFP16QuietNaNMask) == 0); +} + + +template <typename T> +inline bool IsQuietNaN(T num) { + return std::isnan(num) && !IsSignallingNaN(num); +} + + +// Convert the NaN in 'num' to a quiet NaN. +inline double ToQuietNaN(double num) { + const uint64_t kFP64QuietNaNMask = UINT64_C(0x0008000000000000); + VIXL_ASSERT(std::isnan(num)); + return rawbits_to_double(double_to_rawbits(num) | kFP64QuietNaNMask); +} + + +inline float ToQuietNaN(float num) { + const uint32_t kFP32QuietNaNMask = 0x00400000; + VIXL_ASSERT(std::isnan(num)); + return rawbits_to_float(float_to_rawbits(num) | kFP32QuietNaNMask); +} + + +// Fused multiply-add. +inline double FusedMultiplyAdd(double op1, double op2, double a) { + return fma(op1, op2, a); +} + + +inline float FusedMultiplyAdd(float op1, float op2, float a) { + return fmaf(op1, op2, a); +} + + +inline uint64_t LowestSetBit(uint64_t value) { + return value & -value; +} + + +template<typename T> +inline int HighestSetBitPosition(T value) { + VIXL_ASSERT(value != 0); + return (sizeof(value) * 8 - 1) - CountLeadingZeros(value); +} + + +template<typename V> +inline int WhichPowerOf2(V value) { + VIXL_ASSERT(IsPowerOf2(value)); + return CountTrailingZeros(value); +} + + +unsigned CountClearHalfWords(uint64_t imm, unsigned reg_size); + + +template <typename T> +T ReverseBits(T value) { + VIXL_ASSERT((sizeof(value) == 1) || (sizeof(value) == 2) || + (sizeof(value) == 4) || (sizeof(value) == 8)); + T result = 0; + for (unsigned i = 0; i < (sizeof(value) * 8); i++) { + result = (result << 1) | (value & 1); + value >>= 1; + } + return result; +} + + +template <typename T> +T ReverseBytes(T value, int block_bytes_log2) { + VIXL_ASSERT((sizeof(value) == 4) || (sizeof(value) == 8)); + VIXL_ASSERT((1U << block_bytes_log2) <= sizeof(value)); + // Split the 64-bit value into an 8-bit array, where b[0] is the least + // significant byte, and b[7] is the most significant. + uint8_t bytes[8]; + uint64_t mask = UINT64_C(0xff00000000000000); + for (int i = 7; i >= 0; i--) { + bytes[i] = (static_cast<uint64_t>(value) & mask) >> (i * 8); + mask >>= 8; + } + + // Permutation tables for REV instructions. + // permute_table[0] is used by REV16_x, REV16_w + // permute_table[1] is used by REV32_x, REV_w + // permute_table[2] is used by REV_x + VIXL_ASSERT((0 < block_bytes_log2) && (block_bytes_log2 < 4)); + static const uint8_t permute_table[3][8] = { {6, 7, 4, 5, 2, 3, 0, 1}, + {4, 5, 6, 7, 0, 1, 2, 3}, + {0, 1, 2, 3, 4, 5, 6, 7} }; + T result = 0; + for (int i = 0; i < 8; i++) { + result <<= 8; + result |= bytes[permute_table[block_bytes_log2 - 1][i]]; + } + return result; +} + + +// Pointer alignment +// TODO: rename/refactor to make it specific to instructions. +template<typename T> +bool IsWordAligned(T pointer) { + VIXL_ASSERT(sizeof(pointer) == sizeof(intptr_t)); // NOLINT(runtime/sizeof) + return ((intptr_t)(pointer) & 3) == 0; +} + +// Increment a pointer (up to 64 bits) until it has the specified alignment. +template<class T> +T AlignUp(T pointer, size_t alignment) { + // Use C-style casts to get static_cast behaviour for integral types (T), and + // reinterpret_cast behaviour for other types. + + uint64_t pointer_raw = (uint64_t)pointer; + VIXL_STATIC_ASSERT(sizeof(pointer) <= sizeof(pointer_raw)); + + size_t align_step = (alignment - pointer_raw) % alignment; + VIXL_ASSERT((pointer_raw + align_step) % alignment == 0); + + return (T)(pointer_raw + align_step); +} + +// Decrement a pointer (up to 64 bits) until it has the specified alignment. +template<class T> +T AlignDown(T pointer, size_t alignment) { + // Use C-style casts to get static_cast behaviour for integral types (T), and + // reinterpret_cast behaviour for other types. + + uint64_t pointer_raw = (uint64_t)pointer; + VIXL_STATIC_ASSERT(sizeof(pointer) <= sizeof(pointer_raw)); + + size_t align_step = pointer_raw % alignment; + VIXL_ASSERT((pointer_raw - align_step) % alignment == 0); + + return (T)(pointer_raw - align_step); +} + +} // namespace vixl + +#endif // VIXL_UTILS_H |