r600/nir: Fix u64vec2 immediate lowering

There were a couple of issues here:

 1. We should be using nir_const_value_for_uint instead of setting the
    union fields directly to ensure the rest of the union is zeroed.

 2. It was always filling out the first two components of val even if
    the incoming constant had 2 64-bit components.

Fixes: 165fb5117bf7 ("r600/sfn: add lowering passes to get 64 bit ops lowered to 32 bit vec2")
Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/19689>
(cherry picked from commit f3f1c28f8e6d40823e3d12415a8d0ea622f9fa20)

diff --git a/.pick_status.json b/.pick_status.json
index 81e5166..cb02465 100644 (file)
--- a/.pick_status.json
+++ b/.pick_status.json
@@ -4054,7 +4054,7 @@
         "description": "r600/nir: Fix u64vec2 immediate lowering",
         "nominated": true,
         "nomination_type": 1,
-        "resolution": 0,
+        "resolution": 1,
         "main_sha": null,
         "because_sha": "165fb5117bf70402e66d34538d4085e060f57fea"
     },

diff --git a/src/gallium/drivers/r600/sfn/sfn_nir_lower_64bit.cpp b/src/gallium/drivers/r600/sfn/sfn_nir_lower_64bit.cpp
index 9828802..09f294c 100644 (file)
--- a/src/gallium/drivers/r600/sfn/sfn_nir_lower_64bit.cpp
+++ b/src/gallium/drivers/r600/sfn/sfn_nir_lower_64bit.cpp
@@ -929,12 +929,12 @@ Lower64BitToVec2::lower(nir_instr *instr)
    }
    case nir_instr_type_load_const: {
       auto lc = nir_instr_as_load_const(instr);
-      assert(lc->def.num_components < 3);
-      nir_const_value val[4] = {{0}};
+      assert(lc->def.num_components <= 2);
+      nir_const_value val[4];
       for (uint i = 0; i < lc->def.num_components; ++i) {
          uint64_t v = lc->value[i].u64;
-         val[0].u32 = v & 0xffffffff;
-         val[1].u32 = (v >> 32) & 0xffffffff;
+         val[i * 2 + 0] = nir_const_value_for_uint(v & 0xffffffff, 32);
+         val[i * 2 + 1] = nir_const_value_for_uint(v >> 32, 32);
       }
 
       return nir_build_imm(b, 2 * lc->def.num_components, 32, val);