From 4e337b42f9a286c7ef78bae204b7638c9eed758b Mon Sep 17 00:00:00 2001 From: Jason Ekstrand Date: Thu, 25 Jan 2018 22:32:16 -0800 Subject: [PATCH] nir/format_convert: Add pack/unpack for R11F_G11F_B10F Reviewed-by: Topi Pohjolainen --- src/compiler/nir/nir_format_convert.h | 38 +++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) diff --git a/src/compiler/nir/nir_format_convert.h b/src/compiler/nir/nir_format_convert.h index e8c84944c21..ee028a13bf2 100644 --- a/src/compiler/nir/nir_format_convert.h +++ b/src/compiler/nir/nir_format_convert.h @@ -130,3 +130,41 @@ nir_format_srgb_to_linear(nir_builder *b, nir_ssa_def *c) return nir_fsat(b, nir_bcsel(b, nir_fge(b, nir_imm_float(b, 0.04045f), c), linear, curved)); } + +static inline nir_ssa_def * +nir_format_unpack_11f11f10f(nir_builder *b, nir_ssa_def *packed) +{ + nir_ssa_def *chans[3]; + chans[0] = nir_mask_shift(b, packed, 0x000007ff, 4); + chans[1] = nir_mask_shift(b, packed, 0x003ff100, -7); + chans[2] = nir_mask_shift(b, packed, 0xffc00000, -17); + + for (unsigned i = 0; i < 3; i++) + chans[i] = nir_unpack_half_2x16_split_x(b, chans[i]); + + return nir_vec(b, chans, 3); +} + +static inline nir_ssa_def * +nir_format_pack_r11g11b10f(nir_builder *b, nir_ssa_def *color) +{ + /* 10 and 11-bit floats are unsigned. Clamp to non-negative */ + nir_ssa_def *clamped = nir_fmax(b, color, nir_imm_float(b, 0)); + + nir_ssa_def *undef = nir_ssa_undef(b, 1, color->bit_size); + nir_ssa_def *p1 = nir_pack_half_2x16_split(b, nir_channel(b, clamped, 0), + nir_channel(b, clamped, 1)); + nir_ssa_def *p2 = nir_pack_half_2x16_split(b, nir_channel(b, clamped, 2), + undef); + + /* A 10 or 11-bit float has the same exponent as a 16-bit float but with + * fewer mantissa bits and no sign bit. All we have to do is throw away + * the sign bit and the bottom mantissa bits and shift it into place. + */ + nir_ssa_def *packed = nir_imm_int(b, 0); + packed = nir_mask_shift_or(b, packed, p1, 0x00007ff0, -4); + packed = nir_mask_shift_or(b, packed, p1, 0x7ff00000, -9); + packed = nir_mask_shift_or(b, packed, p2, 0x00007fe0, 17); + + return packed; +} -- 2.30.2