From 55d153b9f598c77510a483ba768eca2103bf850b Mon Sep 17 00:00:00 2001
From: Jesse Natalie <jenatali@microsoft.com>
Date: Thu, 18 Mar 2021 18:46:09 -0700
Subject: [PATCH] nir: Temporarily disable optimizations for MSVC ARM64

There's currently an MSVC optimizer bug which causes a stack overflow
in the compiler if it attempts to optimize fsat.

Acked-by: Rob Clark <robdclark@chromium.org>
Acked-by: Jason Ekstrand <jason@jlekstrand.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/9700>
---
 src/compiler/nir/nir_constant_expressions.py | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/compiler/nir/nir_constant_expressions.py b/src/compiler/nir/nir_constant_expressions.py
index 90ee5c339b6..606e974353f 100644
--- a/src/compiler/nir/nir_constant_expressions.py
+++ b/src/compiler/nir/nir_constant_expressions.py
@@ -459,6 +459,11 @@ struct ${type}${width}_vec {
 </%def>
 
 % for name, op in sorted(opcodes.items()):
+% if op.name == "fsat":
+#if defined(_MSC_VER) && (defined(_M_ARM64) || defined(_M_ARM64EC))
+#pragma optimize("", off) /* Temporary work-around for MSVC compiler bug, present in VS2019 16.9.2 */
+#endif
+% endif
 static void
 evaluate_${name}(nir_const_value *_dst_val,
                  UNUSED unsigned num_components,
@@ -482,6 +487,11 @@ evaluate_${name}(nir_const_value *_dst_val,
       ${evaluate_op(op, 0, execution_mode)}
    % endif
 }
+% if op.name == "fsat":
+#if defined(_MSC_VER) && (defined(_M_ARM64) || defined(_M_ARM64EC))
+#pragma optimize("", on) /* Temporary work-around for MSVC compiler bug, present in VS2019 16.9.2 */
+#endif
+% endif
 % endfor
 
 void