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5.50.9.2 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 will be 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 ();
```