diff options
| -rw-r--r-- | src/gallium/drivers/vc4/vc4_program.c | 66 |
1 files changed, 40 insertions, 26 deletions
diff --git a/src/gallium/drivers/vc4/vc4_program.c b/src/gallium/drivers/vc4/vc4_program.c index 1d767af1bdb..1f46b64005b 100644 --- a/src/gallium/drivers/vc4/vc4_program.c +++ b/src/gallium/drivers/vc4/vc4_program.c @@ -687,24 +687,44 @@ ntq_fceil(struct vc4_compile *c, struct qreg src) } static struct qreg +ntq_shrink_sincos_input_range(struct vc4_compile *c, struct qreg x) +{ + /* Since we're using a Taylor approximation, we want to have a small + * number of coefficients and take advantage of sin/cos repeating + * every 2pi. We keep our x as close to 0 as we can, since the series + * will be less accurate as |x| increases. (Also, be careful of + * shifting the input x value to be tricky with sin/cos relations, + * because getting accurate values for x==0 is very important for SDL + * rendering) + */ + struct qreg scaled_x = + qir_FMUL(c, x, + qir_uniform_f(c, 1.0f / (M_PI * 2.0f))); + /* Note: FTOI truncates toward 0. */ + struct qreg x_frac = qir_FSUB(c, scaled_x, + qir_ITOF(c, qir_FTOI(c, scaled_x))); + /* Map [0.5, 1] to [-0.5, 0] */ + qir_SF(c, qir_FSUB(c, x_frac, qir_uniform_f(c, 0.5))); + qir_FSUB_dest(c, x_frac, x_frac, qir_uniform_f(c, 1.0))->cond = QPU_COND_NC; + /* Map [-1, -0.5] to [0, 0.5] */ + qir_SF(c, qir_FADD(c, x_frac, qir_uniform_f(c, 0.5))); + qir_FADD_dest(c, x_frac, x_frac, qir_uniform_f(c, 1.0))->cond = QPU_COND_NS; + + return x_frac; +} + +static struct qreg ntq_fsin(struct vc4_compile *c, struct qreg src) { float coeff[] = { - -2.0 * M_PI, - pow(2.0 * M_PI, 3) / (3 * 2 * 1), - -pow(2.0 * M_PI, 5) / (5 * 4 * 3 * 2 * 1), - pow(2.0 * M_PI, 7) / (7 * 6 * 5 * 4 * 3 * 2 * 1), - -pow(2.0 * M_PI, 9) / (9 * 8 * 7 * 6 * 5 * 4 * 3 * 2 * 1), + 2.0 * M_PI, + -pow(2.0 * M_PI, 3) / (3 * 2 * 1), + pow(2.0 * M_PI, 5) / (5 * 4 * 3 * 2 * 1), + -pow(2.0 * M_PI, 7) / (7 * 6 * 5 * 4 * 3 * 2 * 1), + pow(2.0 * M_PI, 9) / (9 * 8 * 7 * 6 * 5 * 4 * 3 * 2 * 1), }; - struct qreg scaled_x = - qir_FMUL(c, - src, - qir_uniform_f(c, 1.0 / (M_PI * 2.0))); - - struct qreg x = qir_FADD(c, - ntq_ffract(c, scaled_x), - qir_uniform_f(c, -0.5)); + struct qreg x = ntq_shrink_sincos_input_range(c, src); struct qreg x2 = qir_FMUL(c, x, x); struct qreg sum = qir_FMUL(c, x, qir_uniform_f(c, coeff[0])); for (int i = 1; i < ARRAY_SIZE(coeff); i++) { @@ -722,21 +742,15 @@ static struct qreg ntq_fcos(struct vc4_compile *c, struct qreg src) { float coeff[] = { - -1.0f, - pow(2.0 * M_PI, 2) / (2 * 1), - -pow(2.0 * M_PI, 4) / (4 * 3 * 2 * 1), - pow(2.0 * M_PI, 6) / (6 * 5 * 4 * 3 * 2 * 1), - -pow(2.0 * M_PI, 8) / (8 * 7 * 6 * 5 * 4 * 3 * 2 * 1), - pow(2.0 * M_PI, 10) / (10 * 9 * 8 * 7 * 6 * 5 * 4 * 3 * 2 * 1), + 1.0f, + -pow(2.0 * M_PI, 2) / (2 * 1), + pow(2.0 * M_PI, 4) / (4 * 3 * 2 * 1), + -pow(2.0 * M_PI, 6) / (6 * 5 * 4 * 3 * 2 * 1), + pow(2.0 * M_PI, 8) / (8 * 7 * 6 * 5 * 4 * 3 * 2 * 1), + -pow(2.0 * M_PI, 10) / (10 * 9 * 8 * 7 * 6 * 5 * 4 * 3 * 2 * 1), }; - struct qreg scaled_x = - qir_FMUL(c, src, - qir_uniform_f(c, 1.0f / (M_PI * 2.0f))); - struct qreg x_frac = qir_FADD(c, - ntq_ffract(c, scaled_x), - qir_uniform_f(c, -0.5)); - + struct qreg x_frac = ntq_shrink_sincos_input_range(c, src); struct qreg sum = qir_uniform_f(c, coeff[0]); struct qreg x2 = qir_FMUL(c, x_frac, x_frac); struct qreg x = x2; /* Current x^2, x^4, or x^6 */ |