Mesa (staging/22.1): r300: Print warning when stubbing derivatives

[GitLab Mirror]

Module: Mesa
Branch: staging/22.1
Commit: 08e22fff13a82895c82d0e508682acf122e7b456
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=08e22fff13a82895c82d0e508682acf122e7b456

Author: Filip Gawin <filip.gawin at zoho.com>
Date:   Sun Jan 23 17:41:43 2022 +0100

r300: Print warning when stubbing derivatives

Fixes: e1c640c3a43d741719864b35cbf855aa82be0611
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/14669>
(cherry picked from commit d48c10fab38217264045064b3f48ecac0c24b7bb)

---

 .pick_status.json                                      | 2 +-
 src/gallium/drivers/r300/compiler/radeon_program_alu.c | 5 +++++
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/.pick_status.json b/.pick_status.json
index c60a6255933..bce07273571 100644
--- a/.pick_status.json
+++ b/.pick_status.json
@@ -31,7 +31,7 @@
         "description": "r300: Print warning when stubbing derivatives",
         "nominated": true,
         "nomination_type": 1,
-        "resolution": 0,
+        "resolution": 1,
         "main_sha": null,
         "because_sha": "e1c640c3a43d741719864b35cbf855aa82be0611"
     },
diff --git a/src/gallium/drivers/r300/compiler/radeon_program_alu.c b/src/gallium/drivers/r300/compiler/radeon_program_alu.c
index 47fdd7885c9..7ea348dc5b9 100644
--- a/src/gallium/drivers/r300/compiler/radeon_program_alu.c
+++ b/src/gallium/drivers/r300/compiler/radeon_program_alu.c
@@ -38,6 +38,7 @@
 #include "radeon_compiler.h"
 #include "radeon_compiler_util.h"
 
+#include "util/log.h"
 
 static struct rc_instruction *emit1(
 	struct radeon_compiler * c, struct rc_instruction * after,
@@ -1100,6 +1101,10 @@ int radeonStubDeriv(struct radeon_compiler* c,
 	inst->U.I.Opcode = RC_OPCODE_MOV;
 	inst->U.I.SrcReg[0].Swizzle = RC_SWIZZLE_0000;
 
+	mesa_logw_once("r300: WARNING: Shader is trying to use derivatives, "
+					"but the hardware doesn't support it. "
+					"Expect possible misrendering (it's not a bug, do not report it).");
+
 	return 1;
 }