Using the GNU Compiler Collection (GCC): MIPS-3D Built-in Functions

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6.60.15.3 MIPS-3D Built-in Functions

The MIPS-3D Application-Specific Extension (ASE) includes additional paired-single instructions that are designed to improve the performance of 3D graphics operations. Support for these instructions is controlled by the -mips3d command-line option.

The functions listed below map directly to a particular MIPS-3D instruction. Please refer to the architecture specification for more details on what each instruction does.

v2sf __builtin_mips_addr_ps (v2sf, v2sf)

Reduction add (addr.ps).

v2sf __builtin_mips_mulr_ps (v2sf, v2sf)

Reduction multiply (mulr.ps).

v2sf __builtin_mips_cvt_pw_ps (v2sf)

Convert paired single to paired word (cvt.pw.ps).

v2sf __builtin_mips_cvt_ps_pw (v2sf)

Convert paired word to paired single (cvt.ps.pw).

float __builtin_mips_recip1_s (float)

double __builtin_mips_recip1_d (double)

v2sf __builtin_mips_recip1_ps (v2sf)

Reduced-precision reciprocal (sequence step 1) (recip1.fmt ).

float __builtin_mips_recip2_s (float, float)

double __builtin_mips_recip2_d (double, double)

v2sf __builtin_mips_recip2_ps (v2sf, v2sf)

Reduced-precision reciprocal (sequence step 2) (recip2.fmt ).

float __builtin_mips_rsqrt1_s (float)

double __builtin_mips_rsqrt1_d (double)

v2sf __builtin_mips_rsqrt1_ps (v2sf)

Reduced-precision reciprocal square root (sequence step 1) (rsqrt1.fmt ).

float __builtin_mips_rsqrt2_s (float, float)

double __builtin_mips_rsqrt2_d (double, double)

v2sf __builtin_mips_rsqrt2_ps (v2sf, v2sf)

Reduced-precision reciprocal square root (sequence step 2) (rsqrt2.fmt ).

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.

int __builtin_mips_cabs_cond_s (float a, float b)

int __builtin_mips_cabs_cond_d (double a, double b)

Absolute comparison of two scalar values (cabs.cond.fmt , bc1t/bc1f).

These functions compare a and b using cabs.cond.s or cabs.cond.d and return the result as a boolean value. For example:

float a, b;
if (__builtin_mips_cabs_eq_s (a, b))
  true ();
else
  false ();

int __builtin_mips_upper_cabs_cond_ps (v2sf a, v2sf b)

int __builtin_mips_lower_cabs_cond_ps (v2sf a, v2sf b)

Absolute comparison of two paired-single values (cabs.cond.ps, bc1t/bc1f).

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

v2sf a, b;
if (__builtin_mips_upper_cabs_eq_ps (a, b))
  upper_halves_are_equal ();
else
  upper_halves_are_unequal ();
if (__builtin_mips_lower_cabs_eq_ps (a, b))
  lower_halves_are_equal ();
else
  lower_halves_are_unequal ();

v2sf __builtin_mips_movt_cabs_cond_ps (v2sf a, v2sf b, v2sf c, v2sf d)

v2sf __builtin_mips_movf_cabs_cond_ps (v2sf a, v2sf b, v2sf c, v2sf d)

Conditional move based on absolute comparison (cabs.cond.ps, movt.ps/movf.ps).

The movt functions return the value x computed by:

cabs.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_any_c_cond_ps (v2sf a, v2sf b)

int __builtin_mips_all_c_cond_ps (v2sf a, v2sf b)

int __builtin_mips_any_cabs_cond_ps (v2sf a, v2sf b)

int __builtin_mips_all_cabs_cond_ps (v2sf a, v2sf b)

Comparison of two paired-single values (c.cond.ps/cabs.cond.ps, bc1any2t/bc1any2f).

These functions compare a and b using c.cond.ps or cabs.cond.ps. The any forms return true if either result is true and the all forms return true if both results are true. For example:

v2sf a, b;
if (__builtin_mips_any_c_eq_ps (a, b))
  one_is_true ();
else
  both_are_false ();
if (__builtin_mips_all_c_eq_ps (a, b))
  both_are_true ();
else
  one_is_false ();

int __builtin_mips_any_c_cond_4s (v2sf a, v2sf b, v2sf c, v2sf d)

int __builtin_mips_all_c_cond_4s (v2sf a, v2sf b, v2sf c, v2sf d)

int __builtin_mips_any_cabs_cond_4s (v2sf a, v2sf b, v2sf c, v2sf d)

int __builtin_mips_all_cabs_cond_4s (v2sf a, v2sf b, v2sf c, v2sf d)

Comparison of four paired-single values (c.cond.ps/cabs.cond.ps, bc1any4t/bc1any4f).

These functions use c.cond.ps or cabs.cond.ps to compare a with b and to compare c with d. The any forms return true if any of the four results are true and the all forms return true if all four results are true. For example:

v2sf a, b, c, d;
if (__builtin_mips_any_c_eq_4s (a, b, c, d))
  some_are_true ();
else
  all_are_false ();
if (__builtin_mips_all_c_eq_4s (a, b, c, d))
  all_are_true ();
else
  some_are_false ();

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