nir: split nir_lower_mov64

ACO will want to lower the conversions, but preserve the bcsels.

Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Georg Lehmann <dadschoorse@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/23926>

src/compiler/nir/nir.h

@@ -3425,7 +3425,7 @@ typedef enum {
    nir_lower_divmod64 = (1 << 2),
    /** Lower all 64-bit umul_high and imul_high opcodes */
    nir_lower_imul_high64 = (1 << 3),
-   nir_lower_mov64 = (1 << 4),
+   nir_lower_bcsel64 = (1 << 4),
    nir_lower_icmp64 = (1 << 5),
    nir_lower_iadd64 = (1 << 6),
    nir_lower_iabs64 = (1 << 7),
@@ -3444,6 +3444,7 @@ typedef enum {
    nir_lower_usub_sat64 = (1 << 20),
    nir_lower_iadd_sat64 = (1 << 21),
    nir_lower_find_lsb64 = (1 << 22),
+   nir_lower_conv64 = (1 << 23),
 } nir_lower_int64_options;
 
 typedef enum {

src/compiler/nir/nir_lower_int64.c

@@ -909,8 +909,9 @@ nir_lower_int64_op_to_options_mask(nir_op opcode)
    case nir_op_u2f16:
    case nir_op_f2i64:
    case nir_op_f2u64:
+      return nir_lower_conv64;
    case nir_op_bcsel:
-      return nir_lower_mov64;
+      return nir_lower_bcsel64;
    case nir_op_ieq:
    case nir_op_ine:
    case nir_op_ult: