From d249e7ddacfd741afb3e6fa3e9179390375c2b11 Mon Sep 17 00:00:00 2001
From: Faith Ekstrand <faith.ekstrand@collabora.com>
Date: Tue, 15 Apr 2025 10:01:32 -0500
Subject: [PATCH] nak: Lower 64-bit shifts in NIR on Kepler A and earlier

SHF is introduced on Kepler B.  Without it, there's nothing we can do
that's more efficient than NIR's lowering.

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/34540>
---
 src/nouveau/compiler/nak/api.rs      |  3 +++
 src/nouveau/compiler/nak/hw_tests.rs | 11 +++++++++++
 2 files changed, 14 insertions(+)

diff --git a/src/nouveau/compiler/nak/api.rs b/src/nouveau/compiler/nak/api.rs
index 7e40cf4a4be..fe8ea3fb2ad 100644
--- a/src/nouveau/compiler/nak/api.rs
+++ b/src/nouveau/compiler/nak/api.rs
@@ -156,6 +156,9 @@ fn nir_options(dev: &nv_device_info) -> nir_shader_compiler_options {
         | nir_lower_shift64
         | nir_lower_imul_2x32_64
         | nir_lower_conv64);
+    if dev.sm < 32 {
+        op.lower_int64_options |= nir_lower_shift64;
+    }
     op.lower_ldexp = true;
     op.lower_fmod = true;
     op.lower_ffract = true;
diff --git a/src/nouveau/compiler/nak/hw_tests.rs b/src/nouveau/compiler/nak/hw_tests.rs
index 8481cd79384..8f2a8cba441 100644
--- a/src/nouveau/compiler/nak/hw_tests.rs
+++ b/src/nouveau/compiler/nak/hw_tests.rs
@@ -918,6 +918,9 @@ fn test_op_popc() {
 #[test]
 fn test_op_shf() {
     let sm = &RunSingleton::get().sm;
+    if sm.sm() < 32 {
+        return;
+    }
 
     let types = [IntType::U32, IntType::I32, IntType::U64, IntType::I64];
 
@@ -1249,6 +1252,10 @@ fn test_isetp64() {
 #[test]
 fn test_shl64() {
     let run = RunSingleton::get();
+    if run.sm.sm() < 32 {
+        return;
+    }
+
     let invocations = 100;
 
     let mut b = TestShaderBuilder::new(run.sm.as_ref());
@@ -1283,6 +1290,10 @@ fn test_shl64() {
 #[test]
 fn test_shr64() {
     let run = RunSingleton::get();
+    if run.sm.sm() < 32 {
+        return;
+    }
+
     let invocations = 100;
 
     let cases = [true, false];