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Compiler-specific Features
4.7.106 __uxtb16 intrinsic
This intrinsic inserts a UXTB16 instruction into the instruction stream generated by the
compiler. It enables you to extract two 8-bit values from an operand and zero-extend
them to 16 bits each.
unsigned int __uxtb16(unsigned int val)
Where val[7:0] and val[23:16] hold the two 8-bit values to be sign-extended.
The __uxtb16 intrinsic returns the 8-bit values zero-extended to 16-bit values.
Example:
unsigned int zero_extend(unsigned int val)
{
unsigned int res;
}
res = __uxtb16(val1,val2); /* res[15:0] = ZeroExtended(val[7:0])
res[31:16] = ZeroExtended(val[23:16])
*/
return res;
See also
• ARMv6 SIMD intrinsics on page 4-109
• Instruction summary on page 4-2 in the Assembler Guide
• SXT, SXTA, UXT, and UXTA on page 4-109 in the Assembler Guide.
4.7.107 ETSI basic operations
RVCT supports for the original ETSI family of basic operations described in the ETSI
G.729 recommendation Coding of speech at 8 kbit/s using conjugate-structure
algebraic-code-excited linear prediction (CS-ACELP).
To make use of the ETSI basic operations in your own code, include the standard header
file dspfns.h. The intrinsics supplied in dspfns.h are listed in Table 4-19.
Table 4-19 ETSI basic operations supported in RVCT
Intrinsics
abs_s L_add_c L_mult L_sub_c norm_l
add L_deposit_h L_negate mac_r round
div_s L_deposit_l L_sat msu_r saturate
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