pan/va: Add start property to source

The bit position of sources is more complicated than (8 * index). Make it a part
of the Valhall reflection information.

Signed-off-by: Alyssa Rosenzweig <alyssa@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/15364>

src/panfrost/bifrost/valhall/asm.py

@@ -258,7 +258,7 @@ def parse_asm(line):
 
     for i, (op, src) in enumerate(zip(operands, ins.srcs)):
         parts = op.split('.')
-        encoded |= encode_source(parts[0], fau) << (i * 8)
+        encoded |= encode_source(parts[0], fau) << src.start
 
         # Has a swizzle been applied yet?
         swizzled = False

src/panfrost/bifrost/valhall/disasm.py

@@ -199,13 +199,13 @@ va_disasm_instr(FILE *fp, uint64_t instr)
 % endif
 <% no_comma = False %>
 % if src.absneg:
-            va_print_float_src(fp, instr >> ${8 * i}, imm_mode,
+            va_print_float_src(fp, instr >> ${src.start}, imm_mode,
                     instr & BIT(${src.offset['neg']}),
                     instr & BIT(${src.offset['abs']}));
 % elif src.is_float:
-            va_print_float_src(fp, instr >> ${8 * i}, imm_mode, false, false);
+            va_print_float_src(fp, instr >> ${src.start}, imm_mode, false, false);
 % else:
-            va_print_src(fp, instr >> ${8 * i}, imm_mode);
+            va_print_src(fp, instr >> ${src.start}, imm_mode);
 % endif
 % if src.swizzle:
 % if src.size == 32:

src/panfrost/bifrost/valhall/valhall.py

@@ -102,6 +102,7 @@ class Source:
     def __init__(self, index, size, is_float = False, swizzle = False,
             halfswizzle = False, widen = False, lanes = False, combine = False, lane = None, absneg = False, notted = False, name = ""):
         self.is_float = is_float or absneg
+        self.start = (index * 8)
         self.size = size
         self.absneg = absneg
         self.notted = notted