[clang] [llvm] Enable fexec-charset option (PR #138895)

[Abhina Sree via cfe-commits]

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@@ -0,0 +1,61 @@
+//===--- TextEncodingConfig.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
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Lex/TextEncodingConfig.h"
+#include "clang/Basic/DiagnosticDriver.h"
+
+using namespace llvm;
+
+llvm::TextEncodingConverter *
+TextEncodingConfig::getConverter(ConversionAction Action) const {
+  switch (Action) {
+  case CA_ToSystemEncoding:
+    return ToSystemEncodingConverter;
+  case CA_ToExecEncoding:
+    return ToExecEncodingConverter;
+  default:
+    return nullptr;
+  }
+}
+
+std::error_code
+TextEncodingConfig::setConvertersFromOptions(TextEncodingConfig &TEC,
+                                             const clang::LangOptions &Opts,
+                                             const clang::TargetInfo &TInfo) {
+  using namespace llvm;
+  TEC.InternalEncoding = "UTF-8";
+  TEC.SystemEncoding = TInfo.getTriple().getDefaultNarrowTextEncoding();
+  TEC.ExecEncoding =
+      Opts.ExecEncoding.empty() ? TEC.InternalEncoding : Opts.ExecEncoding;
+
+  // Create converter between internal and system encoding
+  if (TEC.InternalEncoding != TEC.SystemEncoding) {
+    ErrorOr<TextEncodingConverter> ErrorOrConverter =
+        llvm::TextEncodingConverter::create(TEC.InternalEncoding,
+                                            TEC.SystemEncoding);
+    if (ErrorOrConverter) {
+      TEC.ToSystemEncodingConverter =
+          new TextEncodingConverter(std::move(*ErrorOrConverter));
+    } else
+      return ErrorOrConverter.getError();
+  }
+
+  // Create converter between internal and exec encoding specified
+  // in fexec-charset option.
+  if (TEC.InternalEncoding == TEC.ExecEncoding)
+    return std::error_code();
+  ErrorOr<TextEncodingConverter> ErrorOrConverter =
+      llvm::TextEncodingConverter::create(TEC.InternalEncoding,
+                                          TEC.ExecEncoding);
+  if (ErrorOrConverter) {
+    TEC.ToExecEncodingConverter =
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abhina-sree wrote:

I make another pointer in the next PR in the TargetInfo class, maybe if we move this class there, I will be able to have one 

https://github.com/llvm/llvm-project/pull/138895