nir: Rework conversion opcodes

The NIR story on conversion opcodes is a mess.  We've had way too many
of them, naming is inconsistent, and which ones have explicit sizes was
sort-of random.  This commit re-organizes things and makes them all
consistent:

 - All non-bool conversion opcodes now have the explicit size in the
   destination and are named <src_type>2<dst_type><size>.

 - Integer <-> integer conversion opcodes now only come in i2i and u2u
   forms (i2u and u2i have been removed) since the only difference
   between the different integer conversions is whether or not they
   sign-extend when up-converting.

 - Boolean conversion opcodes all have the explicit size on the bool and
   are named <src_type>2<dst_type>.

Making things consistent also allows nir_type_conversion_op to be moved
to nir_opcodes.c and auto-generated using mako.  This will make adding
int8, int16, and float16 versions much easier when the time comes.

Reviewed-by: Eric Anholt <[email protected]>

1 files changed, 66 insertions, 0 deletions

diff --git a/src/compiler/nir/nir_opcodes_c.py b/src/compiler/nir/nir_opcodes_c.py
index 5f8bdc12a07..c66f3bc7ad4 100644
--- a/src/compiler/nir/nir_opcodes_c.py
+++ b/src/compiler/nir/nir_opcodes_c.py
@@ -29,6 +29,72 @@ from mako.template import Template
 template = Template("""
 #include "nir.h"
 
+nir_op
+nir_type_conversion_op(nir_alu_type src, nir_alu_type dst)
+{
+   nir_alu_type src_base = (nir_alu_type) nir_alu_type_get_base_type(src);
+   nir_alu_type dst_base = (nir_alu_type) nir_alu_type_get_base_type(dst);
+   unsigned src_bit_size = nir_alu_type_get_type_size(src);
+   unsigned dst_bit_size = nir_alu_type_get_type_size(dst);
+
+   if (src == dst && src_base == nir_type_float) {
+      return nir_op_fmov;
+   } else if ((src_base == nir_type_int || src_base == nir_type_uint) &&
+              (dst_base == nir_type_int || dst_base == nir_type_uint) &&
+              src_bit_size == dst_bit_size) {
+      /* Integer <-> integer conversions with the same bit-size on both
+       * ends are just no-op moves.
+       */
+      return nir_op_imov;
+   }
+
+   switch (src_base) {
+%     for src_t in ['int', 'uint', 'float']:
+      case nir_type_${src_t}:
+         switch (dst_base) {
+%           for dst_t in ['int', 'uint', 'float']:
+            case nir_type_${dst_t}:
+%              if src_t in ['int', 'uint'] and dst_t in ['int', 'uint']:
+%                 if dst_t == 'int':
+<%                   continue %>
+%                 else:
+<%                   dst_t = src_t %>
+%                 endif
+%              endif
+               switch (dst_bit_size) {
+%                 for dst_bits in [32, 64]:
+                  case ${dst_bits}:
+                     return ${'nir_op_{}2{}{}'.format(src_t[0], dst_t[0], dst_bits)};
+%                 endfor
+                  default:
+                     unreachable("Invalid nir alu bit size");
+               }
+%           endfor
+            case nir_type_bool:
+%              if src_t == 'float':
+                  return nir_op_f2b;
+%              else:
+                  return nir_op_i2b;
+%              endif
+            default:
+               unreachable("Invalid nir alu base type");
+         }
+%     endfor
+      case nir_type_bool:
+         switch (dst_base) {
+            case nir_type_int:
+            case nir_type_uint:
+               return nir_op_b2i;
+            case nir_type_float:
+               return nir_op_b2f;
+            default:
+               unreachable("Invalid nir alu base type");
+         }
+      default:
+         unreachable("Invalid nir alu base type");
+   }
+}
+
 const nir_op_info nir_op_infos[nir_num_opcodes] = {
 % for name, opcode in sorted(opcodes.iteritems()):
 {