📄 cpu_core.c
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* 0 0 1 x x x x x 2
* : : : : : : : : :
* : : : : : : : : :
* 0 0 0 1 x x x x 59
* 0 0 0 0 1 x x x 60
* 0 0 0 0 0 1 x x 61
* 0 0 0 0 0 0 1 x 62
* 0 0 0 0 0 0 0 1 63
* 0 0 0 0 0 0 0 0 64
*
*
* See also 'CPU COUNT LEAD ZEROs LOOKUP TABLE Note #1'.
*********************************************************************************************************
*/
#ifndef CPU_CFG_LEAD_ZEROS_ASM_PRESENT
CPU_DATA CPU_CntLeadZeros (CPU_DATA val)
{
CPU_DATA nbr_lead_zeros;
#if (CPU_CFG_DATA_SIZE == CPU_WORD_SIZE_08)
nbr_lead_zeros = CPU_CntLeadZeros08((CPU_INT08U)val);
#elif (CPU_CFG_DATA_SIZE == CPU_WORD_SIZE_16)
nbr_lead_zeros = CPU_CntLeadZeros16((CPU_INT16U)val);
#elif (CPU_CFG_DATA_SIZE == CPU_WORD_SIZE_32)
nbr_lead_zeros = CPU_CntLeadZeros32((CPU_INT32U)val);
#elif (CPU_CFG_DATA_SIZE == CPU_WORD_SIZE_64)
nbr_lead_zeros = CPU_CntLeadZeros64((CPU_INT64U)val);
#else /* See Note #1a. */
nbr_lead_zeros = DEF_INT_CPU_U_MAX_VAL;
#endif
return (nbr_lead_zeros);
}
#endif
/*$PAGE*/
/*
*********************************************************************************************************
* CPU_CntLeadZeros08()
*
* Description : Count the number of contiguous, most-significant, leading zero bits in an 8-bit data value.
*
* Argument(s) : val Data value to count leading zero bits.
*
* Return(s) : Number of contiguous, most-significant, leading zero bits in 'val'.
*
* Caller(s) : CPU_CntLeadZeros(),
* CPU_CntTrailZeros08(),
* Application.
*
* This function is a CPU module application programming interface (API) function & MAY be
* called by application function(s).
*
* Note(s) : (1) Supports 8-bit values :
*
* b07 b06 b05 b04 b03 b02 b01 b00 # Leading Zeros
* --- --- --- --- --- --- --- --- ---------------
* 1 x x x x x x x 0
* 0 1 x x x x x x 1
* 0 0 1 x x x x x 2
* 0 0 0 1 x x x x 3
* 0 0 0 0 1 x x x 4
* 0 0 0 0 0 1 x x 5
* 0 0 0 0 0 0 1 x 6
* 0 0 0 0 0 0 0 1 7
* 0 0 0 0 0 0 0 0 8
*
*
* See also 'CPU COUNT LEAD ZEROs LOOKUP TABLE Note #1'.
*********************************************************************************************************
*/
#if (CPU_CFG_DATA_SIZE_MAX >= CPU_WORD_SIZE_08)
CPU_DATA CPU_CntLeadZeros08 (CPU_INT08U val)
{
#if (!((defined(CPU_CFG_LEAD_ZEROS_ASM_PRESENT)) && \
(CPU_CFG_DATA_SIZE >= CPU_WORD_SIZE_08)))
CPU_DATA ix;
#endif
CPU_DATA nbr_lead_zeros;
/* ---------- ASM-OPTIMIZED ----------- */
#if ((defined(CPU_CFG_LEAD_ZEROS_ASM_PRESENT)) && \
(CPU_CFG_DATA_SIZE >= CPU_WORD_SIZE_08))
nbr_lead_zeros = CPU_CntLeadZeros((CPU_DATA)val);
nbr_lead_zeros -= (CPU_CFG_DATA_SIZE - CPU_WORD_SIZE_08) * DEF_OCTET_NBR_BITS;
#else /* ----------- C-OPTIMIZED ------------ */
/* Chk bits [07:00] : */
/* .. Nbr lead zeros = .. */
ix = (CPU_DATA)(val >> 0u); /* .. lookup tbl ix = 'val' >> 0 bits */
nbr_lead_zeros = (CPU_DATA)(CPU_CntLeadZerosTbl[ix] + 0u); /* .. plus nbr msb lead zeros = 0 bits.*/
#endif
return (nbr_lead_zeros);
}
#endif
/*$PAGE*/
/*
*********************************************************************************************************
* CPU_CntLeadZeros16()
*
* Description : Count the number of contiguous, most-significant, leading zero bits in a 16-bit data value.
*
* Argument(s) : val Data value to count leading zero bits.
*
* Return(s) : Number of contiguous, most-significant, leading zero bits in 'val'.
*
* Caller(s) : CPU_CntLeadZeros(),
* CPU_CntTrailZeros16(),
* Application.
*
* This function is a CPU module application programming interface (API) function & MAY be
* called by application function(s).
*
* Note(s) : (1) Supports 16-bit values :
*
* b15 b14 b13 ... b04 b03 b02 b01 b00 # Leading Zeros
* --- --- --- --- --- --- --- --- ---------------
* 1 x x x x x x x 0
* 0 1 x x x x x x 1
* 0 0 1 x x x x x 2
* : : : : : : : : :
* : : : : : : : : :
* 0 0 0 1 x x x x 11
* 0 0 0 0 1 x x x 12
* 0 0 0 0 0 1 x x 13
* 0 0 0 0 0 0 1 x 14
* 0 0 0 0 0 0 0 1 15
* 0 0 0 0 0 0 0 0 16
*
*
* See also 'CPU COUNT LEAD ZEROs LOOKUP TABLE Note #1'.
*********************************************************************************************************
*/
#if (CPU_CFG_DATA_SIZE_MAX >= CPU_WORD_SIZE_16)
CPU_DATA CPU_CntLeadZeros16 (CPU_INT16U val)
{
#if (!((defined(CPU_CFG_LEAD_ZEROS_ASM_PRESENT)) && \
(CPU_CFG_DATA_SIZE >= CPU_WORD_SIZE_16)))
CPU_DATA ix;
#endif
CPU_DATA nbr_lead_zeros;
/* ---------- ASM-OPTIMIZED ----------- */
#if ((defined(CPU_CFG_LEAD_ZEROS_ASM_PRESENT)) && \
(CPU_CFG_DATA_SIZE >= CPU_WORD_SIZE_16))
nbr_lead_zeros = CPU_CntLeadZeros((CPU_DATA)val);
nbr_lead_zeros -= (CPU_CFG_DATA_SIZE - CPU_WORD_SIZE_16) * DEF_OCTET_NBR_BITS;
#else /* ----------- C-OPTIMIZED ------------ */
if (val > 0x00FFu) { /* Chk bits [15:08] : */
/* .. Nbr lead zeros = .. */
ix = (CPU_DATA)(val >> 8u); /* .. lookup tbl ix = 'val' >> 8 bits */
nbr_lead_zeros = (CPU_DATA)(CPU_CntLeadZerosTbl[ix] + 0u); /* .. plus nbr msb lead zeros = 0 bits.*/
} else { /* Chk bits [07:00] : */
/* .. Nbr lead zeros = .. */
ix = (CPU_DATA)(val >> 0u); /* .. lookup tbl ix = 'val' >> 0 bits */
nbr_lead_zeros = (CPU_DATA)(CPU_CntLeadZerosTbl[ix] + 8u); /* .. plus nbr msb lead zeros = 8 bits.*/
}
#endif
return (nbr_lead_zeros);
}
#endif
/*$PAGE*/
/*
*********************************************************************************************************
* CPU_CntLeadZeros32()
*
* Description : Count the number of contiguous, most-significant, leading zero bits in a 32-bit data value.
*
* Argument(s) : val Data value to count leading zero bits.
*
* Return(s) : Number of contiguous, most-significant, leading zero bits in 'val'.
*
* Caller(s) : CPU_CntLeadZeros(),
* CPU_CntTrailZeros32(),
* Application.
*
* This function is a CPU module application programming interface (API) function & MAY be
* called by application function(s).
*
* Note(s) : (1) Supports 32-bit values :
*
* b31 b30 b29 ... b04 b03 b02 b01 b00 # Leading Zeros
* --- --- --- --- --- --- --- --- ---------------
* 1 x x x x x x x 0
* 0 1 x x x x x x 1
* 0 0 1 x x x x x 2
* : : : : : : : : :
* : : : : : : : : :
* 0 0 0 1 x x x x 27
* 0 0 0 0 1 x x x 28
* 0 0 0 0 0 1 x x 29
* 0 0 0 0 0 0 1 x 30
* 0 0 0 0 0 0 0 1 31
* 0 0 0 0 0 0 0 0 32
*
*
* See also 'CPU COUNT LEAD ZEROs LOOKUP TABLE Note #1'.
*********************************************************************************************************
*/
#if (CPU_CFG_DATA_SIZE_MAX >= CPU_WORD_SIZE_32)
CPU_DATA CPU_CntLeadZeros32 (CPU_INT32U val)
{
#if (!((defined(CPU_CFG_LEAD_ZEROS_ASM_PRESENT)) && \
(CPU_CFG_DATA_SIZE >= CPU_WORD_SIZE_32)))
CPU_DATA ix;
#endif
CPU_DATA nbr_lead_zeros;
/* ---------- ASM-OPTIMIZED ----------- */
#if ((defined(CPU_CFG_LEAD_ZEROS_ASM_PRESENT)) && \
(CPU_CFG_DATA_SIZE >= CPU_WORD_SIZE_32))
nbr_lead_zeros = CPU_CntLeadZeros((CPU_DATA)val);
nbr_lead_zeros -= (CPU_CFG_DATA_SIZE - CPU_WORD_SIZE_32) * DEF_OCTET_NBR_BITS;
#else /* ----------- C-OPTIMIZED ------------ */
if (val > 0x0000FFFFu) {
if (val > 0x00FFFFFFu) { /* Chk bits [31:24] : */
/* .. Nbr lead zeros = .. */
ix = (CPU_DATA)(val >> 24u); /* .. lookup tbl ix = 'val' >> 24 bits */
nbr_lead_zeros = (CPU_DATA)(CPU_CntLeadZerosTbl[ix] + 0u); /* .. plus nbr msb lead zeros = 0 bits.*/
} else { /* Chk bits [23:16] : */
/* .. Nbr lead zeros = .. */
ix = (CPU_DATA)(val >> 16u); /* .. lookup tbl ix = 'val' >> 16 bits */
nbr_lead_zeros = (CPU_DATA)(CPU_CntLeadZerosTbl[ix] + 8u); /* .. plus nbr msb lead zeros = 8 bits.*/
}
} else {
if (val > 0x000000FFu) { /* Chk bits [15:08] : */
/* .. Nbr lead zeros = .. */
ix = (CPU_DATA)(val >> 8u); /* .. lookup tbl ix = 'val' >> 8 bits */
nbr_lead_zeros = (CPU_DATA)(CPU_CntLeadZerosTbl[ix] + 16u); /* .. plus nbr msb lead zeros = 16 bits.*/
} else { /* Chk bits [07:00] : */
/* .. Nbr lead zeros = .. */
ix = (CPU_DATA)(val >> 0u); /* .. lookup tbl ix = 'val' >> 0 bits */
nbr_lead_zeros = (CPU_DATA)(CPU_CntLeadZerosTbl[ix] + 24u); /* .. plus nbr msb lead zeros = 24 bits.*/
}
}
#endif
return (nbr_lead_zeros);
}
#endif
/*$PAGE*/
/*
*********************************************************************************************************
* CPU_CntLeadZeros64()
*
* Description : Count the number of contiguous, most-significant, leading zero bits in a 64-bit data value.
*
* Argument(s) : val Data value to count leading zero bits.
*
* Return(s) : Number of contiguous, most-significant, leading zero ⌨️ 快捷键说明
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