Mesa (staging/21.3): zink: always use explicit lod for texture() when legal in non-fragment stages

[GitLab Mirror]

Module: Mesa
Branch: staging/21.3
Commit: 66e0bf280e19b0e3b5c851f2a257c3116f01462b
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=66e0bf280e19b0e3b5c851f2a257c3116f01462b

Author: Mike Blumenkrantz <michael.blumenkrantz at gmail.com>
Date:   Wed Oct 27 17:37:30 2021 -0400

zink: always use explicit lod for texture() when legal in non-fragment stages

implicit lod is something else entirely

fixes #5566

cc: mesa-stable

Reviewed-by: Dave Airlie <airlied at redhat.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/13563>
(cherry picked from commit 3ad06b69490fa990c473e16f78ce658b0eb43b47)

---

 .pick_status.json                                    | 2 +-
 src/gallium/drivers/zink/nir_to_spirv/nir_to_spirv.c | 6 ++++++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/.pick_status.json b/.pick_status.json
index b35fff27030..62241299341 100644
--- a/.pick_status.json
+++ b/.pick_status.json
@@ -166,7 +166,7 @@
         "description": "zink: always use explicit lod for texture() when legal in non-fragment stages",
         "nominated": true,
         "nomination_type": 0,
-        "resolution": 0,
+        "resolution": 1,
         "main_sha": null,
         "because_sha": null
     },
diff --git a/src/gallium/drivers/zink/nir_to_spirv/nir_to_spirv.c b/src/gallium/drivers/zink/nir_to_spirv/nir_to_spirv.c
index b94f5e7533e..7af2746ab6f 100644
--- a/src/gallium/drivers/zink/nir_to_spirv/nir_to_spirv.c
+++ b/src/gallium/drivers/zink/nir_to_spirv/nir_to_spirv.c
@@ -40,6 +40,8 @@ struct ntv_context {
     */
    bool spirv_1_4_interfaces;
 
+   bool explicit_lod; //whether to set lod=0 for texture()
+
    struct spirv_builder builder;
 
    struct hash_table *glsl_types;
@@ -3217,6 +3219,9 @@ emit_tex(struct ntv_context *ctx, nir_tex_instr *tex)
 
    if (!tex_instr_is_lod_allowed(tex))
       lod = 0;
+   else if (ctx->stage != MESA_SHADER_FRAGMENT &&
+            tex->op == nir_texop_tex && ctx->explicit_lod && !lod && !proj && !bias && !dref && !dx && !dy)
+      lod = emit_float_const(ctx, 32, 0.0);
    if (tex->op == nir_texop_txs) {
       SpvId image = spirv_builder_emit_image(&ctx->builder, image_type, load);
       SpvId result = spirv_builder_emit_image_query_size(&ctx->builder,
@@ -3860,6 +3865,7 @@ nir_to_spirv(struct nir_shader *s, const struct zink_so_info *so_info, uint32_t
    ctx.stage = s->info.stage;
    ctx.so_info = so_info;
    ctx.GLSL_std_450 = spirv_builder_import(&ctx.builder, "GLSL.std.450");
+   ctx.explicit_lod = true;
    spirv_builder_emit_source(&ctx.builder, SpvSourceLanguageUnknown, 0);
 
    if (s->info.stage == MESA_SHADER_COMPUTE) {