From 1ef03dade12b4d5056c3fe5637f9dfd98a42aae6 Mon Sep 17 00:00:00 2001
From: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Date: Mon, 11 May 2020 09:54:11 +0200
Subject: [PATCH] radv: add a LLVM version string workaround for SotTR and ACO

When the LLVM version is too old or missing, SotTR applies shader
workarounds and that reduces performance by 2-5% with ACO.

SotTR workarounds are applied with LLVM 8 and older, so reporting
LLVM 9.0.1 should be fine.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Edmondo Tommasina <edmondo.tommasina@gmail.com>
Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4984>
---
 src/amd/vulkan/radv_device.c   | 25 ++++++++++++++++++++++---
 src/util/00-mesa-defaults.conf |  5 +++++
 src/util/xmlpool/t_options.h   |  9 +++++++++
 3 files changed, 36 insertions(+), 3 deletions(-)

diff --git a/src/amd/vulkan/radv_device.c b/src/amd/vulkan/radv_device.c
index 10d9b34e14b..fc102e23ced 100644
--- a/src/amd/vulkan/radv_device.c
+++ b/src/amd/vulkan/radv_device.c
@@ -238,6 +238,25 @@ radv_physical_device_init_mem_types(struct radv_physical_device *device)
 	}
 }
 
+static const char *
+radv_get_compiler_string(struct radv_physical_device *pdevice)
+{
+	if (pdevice->use_aco) {
+		/* Some games like SotTR apply shader workarounds if the LLVM
+		 * version is too old or if the LLVM version string is
+		 * missing. This gives 2-5% performance with SotTR and ACO.
+		 */
+		if (driQueryOptionb(&pdevice->instance->dri_options,
+				    "radv_report_llvm9_version_string")) {
+			return "ACO/LLVM 9.0.1";
+		}
+
+		return "ACO";
+	}
+
+	return "LLVM " MESA_LLVM_VERSION_STRING;
+}
+
 static VkResult
 radv_physical_device_try_create(struct radv_instance *instance,
 				drmDevicePtr drm_device,
@@ -334,8 +353,7 @@ radv_physical_device_try_create(struct radv_instance *instance,
 
 	snprintf(device->name, sizeof(device->name),
 		 "AMD RADV %s (%s)",
-		 device->rad_info.name,
-		 device->use_aco ? "ACO" : "LLVM " MESA_LLVM_VERSION_STRING);
+		 device->rad_info.name, radv_get_compiler_string(device));
 
 	if (radv_device_get_cache_uuid(device->rad_info.family, device->cache_uuid)) {
 		result = vk_errorf(instance, VK_ERROR_INITIALIZATION_FAILED,
@@ -578,6 +596,7 @@ DRI_CONF_BEGIN
 		DRI_CONF_ADAPTIVE_SYNC("true")
 		DRI_CONF_VK_X11_OVERRIDE_MIN_IMAGE_COUNT(0)
 		DRI_CONF_VK_X11_STRICT_IMAGE_COUNT("false")
+		DRI_CONF_RADV_REPORT_LLVM9_VERSION_STRING("false")
 	DRI_CONF_SECTION_END
 
 	DRI_CONF_SECTION_DEBUG
@@ -1492,7 +1511,7 @@ radv_get_physical_device_properties_1_2(struct radv_physical_device *pdevice,
 	snprintf(p->driverName, VK_MAX_DRIVER_NAME_SIZE, "radv");
 	snprintf(p->driverInfo, VK_MAX_DRIVER_INFO_SIZE,
 		 "Mesa " PACKAGE_VERSION MESA_GIT_SHA1 " (%s)",
-		 pdevice->use_aco ? "ACO" : "LLVM " MESA_LLVM_VERSION_STRING);
+		 radv_get_compiler_string(pdevice));
 	p->conformanceVersion = (VkConformanceVersion) {
 		.major = 1,
 		.minor = 2,
diff --git a/src/util/00-mesa-defaults.conf b/src/util/00-mesa-defaults.conf
index 849b6b169de..fc9fa9e2a35 100644
--- a/src/util/00-mesa-defaults.conf
+++ b/src/util/00-mesa-defaults.conf
@@ -673,4 +673,9 @@ TODO: document the other workarounds.
             <option name="vs_position_always_invariant" value="true" />
         </application>
     </device>
+    <device driver="radv">
+        <application name="Shadow Of The Tomb Raider" executable="ShadowOfTheTombRaider">
+            <option name="radv_report_llvm9_version_string" value="true" />
+        </application>
+    </device>
 </driconf>
diff --git a/src/util/xmlpool/t_options.h b/src/util/xmlpool/t_options.h
index 0dbac8e0479..0321becc49b 100644
--- a/src/util/xmlpool/t_options.h
+++ b/src/util/xmlpool/t_options.h
@@ -421,3 +421,12 @@ DRI_CONF_OPT_END
 DRI_CONF_OPT_BEGIN_V(gles_samples_passed_value, def, minimum, maximum) \
         DRI_CONF_DESC(en,gettext("GL_SAMPLES_PASSED value when emulated by GL_ANY_SAMPLES_PASSED")) \
 DRI_CONF_OPT_END
+
+/**
+ * \brief RADV specific configuration options
+ */
+
+#define DRI_CONF_RADV_REPORT_LLVM9_VERSION_STRING(def) \
+DRI_CONF_OPT_BEGIN_B(radv_report_llvm9_version_string, def) \
+        DRI_CONF_DESC(en,gettext("Report LLVM 9.0.1 for games that apply shader workarounds if missing (for ACO only)")) \
+DRI_CONF_OPT_END
-- 
2.30.2