[llvm] [clang] [clang-tools-extra] Add clang-tidy check to suggest replacement of conditional statement with std::min/std::max (PR #77816)

[Félix-Antoine Constantin via cfe-commits]

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@@ -0,0 +1,189 @@
+//===--- UseStdMinMaxCheck.cpp - clang-tidy -------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "UseStdMinMaxCheck.h"
+#include "../utils/ASTUtils.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/RecursiveASTVisitor.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+#include "clang/Lex/Preprocessor.h"
+#include <iostream>
+using namespace std;
+
+using namespace clang::ast_matchers;
+
+namespace clang::tidy::readability {
+
+class ExprVisitor : public clang::RecursiveASTVisitor<ExprVisitor> {
+public:
+  explicit ExprVisitor(clang::ASTContext *Context) : Context(Context) {}
+  bool visitStmt(const clang::Stmt *S, bool &found,
+                 clang::QualType &GlobalImplicitCastType) {
+
+    if (isa<clang::ImplicitCastExpr>(S) && !found) {
+      found = true;
+      const clang::ImplicitCastExpr *ImplicitCast =
+          cast<clang::ImplicitCastExpr>(S);
+      GlobalImplicitCastType = ImplicitCast->getType();
+      // Stop visiting children.
+      return false;
+    }
+    // Continue visiting children.
+    for (const clang::Stmt *Child : S->children()) {
+      if (Child) {
+        this->visitStmt(Child, found, GlobalImplicitCastType);
+      }
+    }
+
+    return true; // Continue visiting other nodes.
+  }
+
+private:
+  clang::ASTContext *Context;
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felix642 wrote:

Would you be able to tell me where are you using this ASTContext variable? I'm not seeing any usage and I feel like I'm missing something

https://github.com/llvm/llvm-project/pull/77816