nir: Fix constant evaluation of bfm.

NIR's bfm, like Intel/AMD's hardware instructions and GLSL IR's
ir_binop_bfm takes <bits> as src0 and <offset> as src1.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Iago Toral Quiroga <itoral@igalia.com>

diff --git a/src/glsl/nir/nir_opcodes.py b/src/glsl/nir/nir_opcodes.py
index d31507fe53166fcca47e56ff97f5bf6dc9fbd21d..398ae50f9f77d04496a19d52c6b9de98ad15d590 100644 (file)
--- a/src/glsl/nir/nir_opcodes.py
+++ b/src/glsl/nir/nir_opcodes.py
@@ -512,7 +512,7 @@ binop_horiz("pack_half_2x16_split", 1, tuint, 1, tfloat, 1, tfloat,
             "pack_half_1x16(src0.x) | (pack_half_1x16(src1.x) << 16)")
 
 binop_convert("bfm", tuint, tint, "", """
-int offset = src0, bits = src1;
+int bits = src0, offset = src1;
 if (offset < 0 || bits < 0 || offset + bits > 32)
    dst = 0; /* undefined per the spec */
 else