nir/constant_expressions: mind rounding mode converting from float to float16 destina...

v2:
- Move the op-code specific knowledge to nir_opcodes.py even if it
  means a rount trip conversion (Connor).

Signed-off-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>
Signed-off-by: Andres Gomez <agomez@igalia.com>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>

diff --git a/src/compiler/nir/nir_constant_expressions.py b/src/compiler/nir/nir_constant_expressions.py
index baba66e5d024fb4762f8c8be7b89c0d776ee1a84..377f54d65217dac8111628a006f0f2194c252dcd 100644 (file)
--- a/src/compiler/nir/nir_constant_expressions.py
+++ b/src/compiler/nir/nir_constant_expressions.py
@@ -364,7 +364,11 @@ struct ${type}${width}_vec {
             ## Sanitize the C value to a proper NIR 0/-1 bool
             _dst_val[_i].${get_const_field(output_type)} = -(int)dst;
          % elif output_type == "float16":
-            _dst_val[_i].u16 = _mesa_float_to_half(dst);
+            if (nir_is_rounding_mode_rtz(execution_mode, 16)) {
+               _dst_val[_i].u16 = _mesa_float_to_float16_rtz(dst);
+            } else {
+               _dst_val[_i].u16 = _mesa_float_to_float16_rtne(dst);
+            }
          % else:
             _dst_val[_i].${get_const_field(output_type)} = dst;
          % endif
@@ -408,7 +412,11 @@ struct ${type}${width}_vec {
             ## Sanitize the C value to a proper NIR 0/-1 bool
             _dst_val[${k}].${get_const_field(output_type)} = -(int)dst.${"xyzw"[k]};
          % elif output_type == "float16":
-            _dst_val[${k}].u16 = _mesa_float_to_half(dst.${"xyzw"[k]});
+            if (nir_is_rounding_mode_rtz(execution_mode, 16)) {
+               _dst_val[${k}].u16 = _mesa_float_to_float16_rtz(dst.${"xyzw"[k]});
+            } else {
+               _dst_val[${k}].u16 = _mesa_float_to_float16_rtne(dst.${"xyzw"[k]});
+            }
          % else:
             _dst_val[${k}].${get_const_field(output_type)} = dst.${"xyzw"[k]};
          % endif