host-utils header¶
The documentation of QEMU’s qemu/host-utils.h header.
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int
clz32(uint32_t val)¶ count leading zeros in a 32-bit value.
Parameters
uint32_t val- The value to search
Description
Returns 32 if the value is zero. Note that the GCC builtin is undefined if the value is zero.
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int
clo32(uint32_t val)¶ count leading ones in a 32-bit value.
Parameters
uint32_t val- The value to search
Description
Returns 32 if the value is -1.
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int
clz64(uint64_t val)¶ count leading zeros in a 64-bit value.
Parameters
uint64_t val- The value to search
Description
Returns 64 if the value is zero. Note that the GCC builtin is undefined if the value is zero.
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int
clo64(uint64_t val)¶ count leading ones in a 64-bit value.
Parameters
uint64_t val- The value to search
Description
Returns 64 if the value is -1.
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int
ctz32(uint32_t val)¶ count trailing zeros in a 32-bit value.
Parameters
uint32_t val- The value to search
Description
Returns 32 if the value is zero. Note that the GCC builtin is undefined if the value is zero.
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int
cto32(uint32_t val)¶ count trailing ones in a 32-bit value.
Parameters
uint32_t val- The value to search
Description
Returns 32 if the value is -1.
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int
ctz64(uint64_t val)¶ count trailing zeros in a 64-bit value.
Parameters
uint64_t val- The value to search
Description
Returns 64 if the value is zero. Note that the GCC builtin is undefined if the value is zero.
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int
cto64(uint64_t val)¶ count trailing ones in a 64-bit value.
Parameters
uint64_t val- The value to search
Description
Returns 64 if the value is -1.
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int
clrsb32(uint32_t val)¶ count leading redundant sign bits in a 32-bit value.
Parameters
uint32_t val- The value to search
Description
Returns the number of bits following the sign bit that are equal to it. No special cases; output range is [0-31].
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int
clrsb64(uint64_t val)¶ count leading redundant sign bits in a 64-bit value.
Parameters
uint64_t val- The value to search
Description
Returns the number of bits following the sign bit that are equal to it. No special cases; output range is [0-63].
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int
ctpop8(uint8_t val)¶ count the population of one bits in an 8-bit value.
Parameters
uint8_t val- The value to search
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int
ctpop16(uint16_t val)¶ count the population of one bits in a 16-bit value.
Parameters
uint16_t val- The value to search
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int
ctpop32(uint32_t val)¶ count the population of one bits in a 32-bit value.
Parameters
uint32_t val- The value to search
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int
ctpop64(uint64_t val)¶ count the population of one bits in a 64-bit value.
Parameters
uint64_t val- The value to search
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uint8_t
revbit8(uint8_t x)¶ reverse the bits in an 8-bit value.
Parameters
uint8_t x- The value to modify.
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uint16_t
revbit16(uint16_t x)¶ reverse the bits in a 16-bit value.
Parameters
uint16_t x- The value to modify.
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uint32_t
revbit32(uint32_t x)¶ reverse the bits in a 32-bit value.
Parameters
uint32_t x- The value to modify.
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uint64_t
revbit64(uint64_t x)¶ reverse the bits in a 64-bit value.
Parameters
uint64_t x- The value to modify.
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uint64_t
pow2floor(uint64_t value)¶
Parameters
uint64_t value- undescribed
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void
urshift(uint64_t * plow, uint64_t * phigh, int32_t shift)¶ 128-bit Unsigned Right Shift.
Parameters
uint64_t * plow- in/out - lower 64-bit integer.
uint64_t * phigh- in/out - higher 64-bit integer.
int32_t shift- in - bytes to shift, between 0 and 127.
Description
Result is zero-extended and stored in plow/phigh, which are input/output variables. Shift values outside the range will be mod to 128. In other words, the caller is responsible to verify/assert both the shift range and plow/phigh pointers.
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void
ulshift(uint64_t * plow, uint64_t * phigh, int32_t shift, bool * overflow)¶ 128-bit Unsigned Left Shift.
Parameters
uint64_t * plow- in/out - lower 64-bit integer.
uint64_t * phigh- in/out - higher 64-bit integer.
int32_t shift- in - bytes to shift, between 0 and 127.
bool * overflow- out - true if any 1-bit is shifted out.
Description
Result is zero-extended and stored in plow/phigh, which are input/output variables. Shift values outside the range will be mod to 128. In other words, the caller is responsible to verify/assert both the shift range and plow/phigh pointers.