[llvm] [AMDGPU] Rewrite GFX12 SGPR hazard handling to dedicated pass (PR #118750)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,502 @@
+//===- AMDGPUWaitSGPRHazards.cpp - Insert waits for SGPR read hazards -----===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+/// \file
+/// Insert s_wait_alu instructions to mitigate SGPR read hazards on GFX12.
+//
+//===----------------------------------------------------------------------===//
+
+#include "AMDGPU.h"
+#include "GCNSubtarget.h"
+#include "MCTargetDesc/AMDGPUMCTargetDesc.h"
+#include "SIInstrInfo.h"
+#include "llvm/ADT/SetVector.h"
+
+using namespace llvm;
+
+#define DEBUG_TYPE "amdgpu-wait-sgpr-hazards"
+
+static cl::opt<bool> GlobalEnableSGPRHazardWaits(
+    "amdgpu-sgpr-hazard-wait", cl::init(true), cl::Hidden,
+    cl::desc("Enable required s_wait_alu on SGPR hazards"));
+
+static cl::opt<bool> GlobalCullSGPRHazardsOnFunctionBoundary(
+    "amdgpu-sgpr-hazard-boundary-cull", cl::init(false), cl::Hidden,
+    cl::desc("Cull hazards on function boundaries"));
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arsenm wrote:

Same, this is just enable miscompiles? And what does cull mean here in context?

https://github.com/llvm/llvm-project/pull/118750