Paired-Single Built-in Functions (Using the GNU Compiler Collection (GCC))

#### 7.13.17.2 Paired-Single Built-in Functions ¶

The following paired-single functions map directly to a particular MIPS instruction. Please refer to the architecture specification for details on what each instruction does.

`v2sf __builtin_mips_pll_ps (v2sf, v2sf)`

  Pair lower lower (`pll.ps`).

`v2sf __builtin_mips_pul_ps (v2sf, v2sf)`

  Pair upper lower (`pul.ps`).

`v2sf __builtin_mips_plu_ps (v2sf, v2sf)`

  Pair lower upper (`plu.ps`).

`v2sf __builtin_mips_puu_ps (v2sf, v2sf)`

  Pair upper upper (`puu.ps`).

`v2sf __builtin_mips_cvt_ps_s (float, float)`

  Convert pair to paired single (`cvt.ps.s`).

`float __builtin_mips_cvt_s_pl (v2sf)`

  Convert pair lower to single (`cvt.s.pl`).

`float __builtin_mips_cvt_s_pu (v2sf)`

  Convert pair upper to single (`cvt.s.pu`).

`v2sf __builtin_mips_abs_ps (v2sf)`

  Absolute value (`abs.ps`).

`v2sf __builtin_mips_alnv_ps (v2sf, v2sf, int)`

  Align variable (`alnv.ps`).

  Note: The value of the third parameter must be 0 or 4 modulo 8, otherwise the result is unpredictable. Please read the instruction description for details.

The following multi-instruction functions are also available. In each case, cond can be any of the 16 floating-point conditions: `f`, `un`, `eq`, `ueq`, `olt`, `ult`, `ole`, `ule`, `sf`, `ngle`, `seq`, `ngl`, `lt`, `nge`, `le` or `ngt`.

`v2sf __builtin_mips_movt_c_cond_ps (v2sf a, v2sf b, v2sf c, v2sf d)`
`v2sf __builtin_mips_movf_c_cond_ps (v2sf a, v2sf b, v2sf c, v2sf d)`

  Conditional move based on floating-point comparison (`c.cond.ps`, `movt.ps`/`movf.ps`).

  The `movt` functions return the value x computed by:

      c.cond.ps cc,a,b
      mov.ps x,c
      movt.ps x,d,cc

  The `movf` functions are similar but use `movf.ps` instead of `movt.ps`.

`int __builtin_mips_upper_c_cond_ps (v2sf a, v2sf b)`
`int __builtin_mips_lower_c_cond_ps (v2sf a, v2sf b)`

  Comparison of two paired-single values (`c.cond.ps`, `bc1t`/`bc1f`).

  These functions compare a and b using `c.cond.ps` and return either the upper or lower half of the result. For example:

      v2sf a, b;
      if (__builtin_mips_upper_c_eq_ps (a, b))
        upper_halves_are_equal ();
      else
        upper_halves_are_unequal ();

      if (__builtin_mips_lower_c_eq_ps (a, b))
        lower_halves_are_equal ();
      else
        lower_halves_are_unequal ();