From: Ilia Mirkin <imirkin@alum.mit.edu>
Date: Sun, 20 Mar 2016 17:11:01 +0000 (-0400)
Subject: nv50/ir: saturate depth writes
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=6711f159d94f37f3f45d36a8cb172cfc00692875;p=mesa.git

nv50/ir: saturate depth writes

Apparently there's no post-FS clamping logic, so we have to do this by
hand. The depth will never be outside of the 0..1 range, even on
floating point zeta buffers, so this should be safe.

Fixes dEQP-GLES3.functional.fbo.depth.*clamp.* which tests writing
invalid values on various zeta buffer formats.

Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
---

diff --git a/src/gallium/drivers/nouveau/codegen/nv50_ir_from_tgsi.cpp b/src/gallium/drivers/nouveau/codegen/nv50_ir_from_tgsi.cpp
index 611d5f9c3ed..4f012cd3b91 100644
--- a/src/gallium/drivers/nouveau/codegen/nv50_ir_from_tgsi.cpp
+++ b/src/gallium/drivers/nouveau/codegen/nv50_ir_from_tgsi.cpp
@@ -3536,8 +3536,11 @@ Converter::exportOutputs()
          Symbol *sym = mkSymbol(FILE_SHADER_OUTPUT, 0, TYPE_F32,
                                 info->out[i].slot[c] * 4);
          Value *val = oData.load(sub.cur->values, i, c, NULL);
-         if (val)
+         if (val) {
+            if (info->out[i].sn == TGSI_SEMANTIC_POSITION)
+               mkOp1(OP_SAT, TYPE_F32, val, val);
             mkStore(OP_EXPORT, TYPE_F32, sym, NULL, val);
+         }
       }
    }
 }