[llvm] [GlobalIsel] Canonicalize G_ICMP (PR #108755)

[Thorsten Schütt via llvm-commits]

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@@ -0,0 +1,86 @@
+//===- CombinerHelperCompares.cpp------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements CombinerHelper for G_ICMP.
+//
+//===----------------------------------------------------------------------===//
+#include "llvm/CodeGen/GlobalISel/CombinerHelper.h"
+#include "llvm/CodeGen/GlobalISel/GenericMachineInstrs.h"
+#include "llvm/CodeGen/GlobalISel/LegalizerHelper.h"
+#include "llvm/CodeGen/GlobalISel/LegalizerInfo.h"
+#include "llvm/CodeGen/GlobalISel/MachineIRBuilder.h"
+#include "llvm/CodeGen/GlobalISel/Utils.h"
+#include "llvm/CodeGen/LowLevelTypeUtils.h"
+#include "llvm/CodeGen/MachineInstr.h"
+#include "llvm/CodeGen/MachineOperand.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/CodeGen/TargetOpcodes.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/Support/Casting.h"
+#include "llvm/Support/ErrorHandling.h"
+#include <cstdlib>
+
+#define DEBUG_TYPE "gi-combiner"
+
+using namespace llvm;
+
+bool CombinerHelper::constantFoldICmp(const GICmp &ICmp,
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tschuett wrote:

We already have ConstantFoldICmp, but I needed this on top of GIConstants.
https://github.com/llvm/llvm-project/blob/76b54df87a860c20ac68e4ed1d766b545d412c1e/llvm/lib/CodeGen/GlobalISel/Utils.cpp#L1013

This used by the builder.

https://github.com/llvm/llvm-project/pull/108755