1 //===-- InstructionUtils.h --------------------------------------*- C++ -*-===//
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //===----------------------------------------------------------------------===//
15 // Common utilities for manipulating instruction bit fields.
19 // Return the bit field(s) from the most significant bit (msbit) to the
20 // least significant bit (lsbit) of a 64-bit unsigned value.
24   return (bits >> lsbit) & ((1ull << (msbit - lsbit + 1)) - 1);  in Bits64()
27 // Return the bit field(s) from the most significant bit (msbit) to the
28 // least significant bit (lsbit) of a 32-bit unsigned value.
31   assert(msbit < 32 && lsbit <= msbit);  in Bits32()
32   return (bits >> lsbit) & ((1u << (msbit - lsbit + 1)) - 1);  in Bits32()
35 // Return the bit value from the 'bit' position of a 32-bit unsigned value.
36 static inline uint32_t Bit32(const uint32_t bits, const uint32_t bit) {  in Bit32()  argument
37   return (bits >> bit) & 1u;  in Bit32()
40 static inline uint64_t Bit64(const uint64_t bits, const uint32_t bit) {  in Bit64()  argument
41   return (bits >> bit) & 1ull;  in Bit64()
44 // Set the bit field(s) from the most significant bit (msbit) to the
45 // least significant bit (lsbit) of a 32-bit unsigned value to 'val'.
48   assert(msbit < 32 && lsbit < 32 && msbit >= lsbit);  in SetBits32()
49   uint32_t mask = ((1u << (msbit - lsbit + 1)) - 1);  in SetBits32()
54 // Set the 'bit' position of a 32-bit unsigned value to 'val'.
55 static inline void SetBit32(uint32_t &bits, const uint32_t bit,  in SetBit32()  argument
57   SetBits32(bits, bit, bit, val);  in SetBit32()
60 // Rotate a 32-bit unsigned value right by the specified amount.
62   assert(amt < 32 && "Invalid rotate amount");  in Rotr32()
63   return (bits >> amt) | (bits << ((32 - amt) & 31));  in Rotr32()
66 // Rotate a 32-bit unsigned value left by the specified amount.
68   assert(amt < 32 && "Invalid rotate amount");  in Rotl32()
69   return (bits << amt) | (bits >> ((32 - amt) & 31));  in Rotl32()
72 // Create a mask that starts at bit zero and includes "bit"
73 static inline uint64_t MaskUpToBit(const uint64_t bit) {  in MaskUpToBit()  argument
74   if (bit >= 63)  in MaskUpToBit()
75     return -1ll;  in MaskUpToBit()
76   return (1ull << (bit + 1ull)) - 1ull;  in MaskUpToBit()
84     x &= x - 1; // clear the least significant bit set  in BitCount()
89 static inline bool BitIsSet(const uint64_t value, const uint64_t bit) {  in BitIsSet()  argument
90   return (value & (1ull << bit)) != 0;  in BitIsSet()
93 static inline bool BitIsClear(const uint64_t value, const uint64_t bit) {  in BitIsClear()  argument
94   return (value & (1ull << bit)) == 0;  in BitIsClear()
100   result &= MaskUpToBit(msbit - lsbit);  in UnsignedBits()
109     result |= ~MaskUpToBit(msbit - lsbit);  in SignedBits()