From 41be2caa6d14ccd1446cbbf28da2464db805c3c7 Mon Sep 17 00:00:00 2001
From: Emma Anholt <emma@anholt.net>
Date: Thu, 2 Mar 2023 10:25:31 -0800
Subject: [PATCH] glsl/lower_precision: Add a unit test that I thought we might
 fail at.
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If you lowered precision too late, it would be easy to break this.

Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/21666>
---
 src/compiler/glsl/tests/lower_precision_test.py | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/src/compiler/glsl/tests/lower_precision_test.py b/src/compiler/glsl/tests/lower_precision_test.py
index fcb85f90b5a..2efee590787 100644
--- a/src/compiler/glsl/tests/lower_precision_test.py
+++ b/src/compiler/glsl/tests/lower_precision_test.py
@@ -2287,6 +2287,18 @@ TESTS = [
          """,
          r'\(expression vec4 \* \(swiz xxxx \(var_ref a\) \)\(expression float f162f \(var_ref b\) \) \)'),
 
+    Test("respect copies",
+         """
+         uniform mediump float a, b;
+
+         void main()
+         {
+            highp float x = a;
+            gl_FragColor.x = x * b;
+         }
+         """,
+         r'expression float \* \(expression float f162f \(var_ref a\) \) \(expression float f162f \(var_ref b\) \) '), # should be uint16_t
+
 ]