[llvm] [KernelInfo] Implement new LLVM IR pass for GPU code analysis (PR #102944)

[Joel E. Denny via llvm-commits]

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@@ -0,0 +1,345 @@
+//===- KernelInfo.cpp - Kernel Analysis -----------------------------------===//
+//
+// 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 defines the KernelInfo, KernelInfoAnalysis, and KernelInfoPrinter
+// classes used to extract function properties from a kernel.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Analysis/KernelInfo.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/Analysis/OptimizationRemarkEmitter.h"
+#include "llvm/IR/DebugInfo.h"
+#include "llvm/IR/Dominators.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/Metadata.h"
+#include "llvm/IR/Module.h"
+#include "llvm/IR/PassManager.h"
+#include "llvm/Passes/PassBuilder.h"
+
+using namespace llvm;
+
+#define DEBUG_TYPE "kernel-info"
+
+static bool isKernelFunction(Function &F) {
+  // TODO: Is this general enough?  Consider languages beyond OpenMP.
+  return F.hasFnAttribute("kernel");
+}
+
+static void identifyFunction(OptimizationRemark &R, const Function &F) {
+  if (auto *SubProgram = F.getSubprogram()) {
+    if (SubProgram->isArtificial())
+      R << "artificial ";
+  }
+  R << "function '" << F.getName() << "'";
+}
+
+static void remarkAlloca(OptimizationRemarkEmitter &ORE, const Function &Caller,
+                         const AllocaInst &Alloca,
+                         TypeSize::ScalarTy StaticSize) {
+  ORE.emit([&] {
+    StringRef Name;
+    DebugLoc Loc;
+    bool Artificial = false;
+    auto DVRs = findDVRDeclares(&const_cast<AllocaInst &>(Alloca));
+    if (!DVRs.empty()) {
+      const DbgVariableRecord &DVR = **DVRs.begin();
+      Name = DVR.getVariable()->getName();
+      Loc = DVR.getDebugLoc();
+      Artificial = DVR.Variable->isArtificial();
+    }
+    OptimizationRemark R(DEBUG_TYPE, "Alloca", DiagnosticLocation(Loc),
+                         Alloca.getParent());
+    R << "in ";
+    identifyFunction(R, Caller);
+    R << ", ";
+    if (Artificial)
+      R << "artificial ";
+    if (Name.empty()) {
+      R << "unnamed alloca ";
+      if (DVRs.empty())
+        R << "(missing debug metadata) ";
+    } else {
+      R << "alloca '" << Name << "' ";
+    }
+    R << "with ";
+    if (StaticSize)
+      R << "static size of " << itostr(StaticSize) << " bytes";
----------------
jdenny-ornl wrote:

It doesn't compile if I simply remove itostr.  Is that what you mean?

https://github.com/llvm/llvm-project/pull/102944