From 35c81de2c1a1bc6df3965e75e4df7e3279f504a7 Mon Sep 17 00:00:00 2001
From: David Woo <david.j.woo@intel.com>
Date: Mon, 18 Sep 2023 23:27:17 +0000
Subject: [PATCH]  CS SIMD mode flag priority

Flags like ForceCSSIMD32 should have priority over all other methods
of forcing simd modes in compute shaders.
---
 IGC/AdaptorCommon/DivergentBarrierPass.cpp       | 16 ++++++++++------
 .../RayTracing/TraceRayInlineLoweringPass.cpp    | 14 ++++++++++----
 2 files changed, 20 insertions(+), 10 deletions(-)

diff --git a/IGC/AdaptorCommon/DivergentBarrierPass.cpp b/IGC/AdaptorCommon/DivergentBarrierPass.cpp
index 21d99c4198cd..f4f6c6702cc2 100644
--- a/IGC/AdaptorCommon/DivergentBarrierPass.cpp
+++ b/IGC/AdaptorCommon/DivergentBarrierPass.cpp
@@ -493,18 +493,22 @@ bool DivergentBarrierPass::processShader(Function* F)
     // so no need to add the divergent barrier WA.
     bool skipTGbarriers = false;
     unsigned forcedSimdSize = 0;
-    if (IGC_IS_FLAG_ENABLED(ForceCSSIMD32) ||
-        m_CGCtx->getModuleMetaData()->csInfo.waveSize == 32 ||
-        m_CGCtx->getModuleMetaData()->csInfo.forcedSIMDSize == 32)
+    if (IGC_IS_FLAG_ENABLED(ForceCSSIMD32))
     {
         forcedSimdSize = 32;
     }
-    else if (IGC_IS_FLAG_ENABLED(ForceCSSIMD16) ||
-        m_CGCtx->getModuleMetaData()->csInfo.waveSize == 16 ||
-        m_CGCtx->getModuleMetaData()->csInfo.forcedSIMDSize == 16)
+    else if (IGC_IS_FLAG_ENABLED(ForceCSSIMD16))
     {
         forcedSimdSize = 16;
     }
+    else if (m_CGCtx->getModuleMetaData()->csInfo.forcedSIMDSize >= 16)
+    {
+        forcedSimdSize = m_CGCtx->getModuleMetaData()->csInfo.forcedSIMDSize;
+    }
+    else if (m_CGCtx->getModuleMetaData()->csInfo.waveSize >= 16)
+    {
+        forcedSimdSize = m_CGCtx->getModuleMetaData()->csInfo.waveSize;
+    }
     ConstantInt* groupSize = dyn_cast<ConstantInt>(getGroupSize(*F));
     if (groupSize &&
         forcedSimdSize >= groupSize->getValue().getZExtValue())
diff --git a/IGC/AdaptorCommon/RayTracing/TraceRayInlineLoweringPass.cpp b/IGC/AdaptorCommon/RayTracing/TraceRayInlineLoweringPass.cpp
index d7f050645720..f94c299fa000 100644
--- a/IGC/AdaptorCommon/RayTracing/TraceRayInlineLoweringPass.cpp
+++ b/IGC/AdaptorCommon/RayTracing/TraceRayInlineLoweringPass.cpp
@@ -967,10 +967,16 @@ bool RTGlobalsPointerLoweringPass::needsSplitting(const CodeGenContext* Ctx)
 
     auto& csInfo = Ctx->getModuleMetaData()->csInfo;
 
-    if (IGC_IS_FLAG_ENABLED(ForceCSSIMD32)           ||
-        IGC_GET_FLAG_VALUE(ForceCSSimdSize4RQ) == 32 ||
-        csInfo.waveSize == 32                        ||
-        csInfo.forcedSIMDSize == 32)
+    if (IGC_IS_FLAG_ENABLED(ForceCSSIMD32) ||
+        IGC_GET_FLAG_VALUE(ForceCSSimdSize4RQ) == 32)
+        return true;
+    if (IGC_IS_FLAG_ENABLED(ForceCSSIMD16))
+        return false;
+    if (csInfo.forcedSIMDSize == 32)
+        return true;
+    if (csInfo.forcedSIMDSize == 16)
+        return false;
+    if (csInfo.waveSize == 32)
         return true;
 
     return false;